Brain CT studies in 26 cases of aged patients with Down syndrome

International Nuclear Information System (INIS)

Arai, Yukio; Yoshihara, Sachiko; Iinuma, Kazuso.

1995-01-01

Computed tomographic images of brains from 26 individuals (10 males and 16 females) with Down syndrome were analysed for roentgenographic measurement. Their ages ranged from 14 to 47 years, the average being 28 years. The results showed that their Sylvian fissure ratio was larger in the aged group. A high incidence of calcification in basal ganglia, choroid plexus and pineal body was noted (85%). An increased Sylvian fissure ratio and a high incidence of intracranial calcification may be practically used as representatives of premature aging. Furthermore, a high incidence of mega cisterna magna implicates that it is worthy of study whether individuals with Down syndrome have a predisposition to underdevelopment of cerebellum. (author)

Dandy-Walker variant in Coffin-Siris syndrome.

Science.gov (United States)

Imai, T; Hattori, H; Miyazaki, M; Higuchi, Y; Adachi, S; Nakahata, T

2001-04-22

We describe a five-month-old male infant with Coffin-Siris syndrome, the so-called Dandy-Walker variant (hypoplasia of the cerebellar vermis with cystic dilatation of the fourth ventricle, but without enlargement of the posterior fossa), and partial agenesis of the corpus callosum. Dandy-Walker malformation and mega cisterna magna, but not Dandy-Walker variant, have been reported in Coffin-Siris syndrome. The presence of Dandy-Walker variant in the infant we described confirms that the full continuum of the Dandy-Walker complex can occur in Coffin-Siris syndrome. The yet unidentified gene(s) for the syndrome may be related to the development of the hindbrain. Copyright 2001 Wiley-Liss, Inc.

A CONFIABILIDADE DO TAMANHO DAS CISTERNAS RURAIS

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Eduardo Henrique Borges Cohim Silva

2015-11-01

Full Text Available O Programa de Formação e Mobilização Social para a Convivência com o Semiárido – P1MC construiu mais de 400 mil cisternas, com o volume definido em 16 mil litros com base na demanda de uma família média de cinco pessoas em um período de 280 dias. Porém dada a diversidade vários fatores como área de captação, precipitação e número de usuários, as demanda devem portanto serem diferentes. O objetivo deste trabalho é avaliar a confiabilidade do suprimento de água por meio de sistemas de captação de água de chuva, no âmbito do Programa P1MC. Foi utilizado o modelo comportamental que simula a operação do reservatório num período de tempo, simulando fluxos de massas com algoritmos que descrevem a operação de um reservatório, adotando-se um intervalo de um dia para o balanço. O universo amostral foi constituído por 947 cisternas cujas informações, tais como área de captação e número de moradores, foram obtidas na ASA – Articulação para o Semiárido. Para cada cenário analisado, definido pela precipitação, área de captação e demanda (número de moradores e demanda per capita foi calculada a confiabilidade. Verificou-se que para os 947 sistemas de aproveitamento implantados, o valor médio do número de moradores encontrado foi de 5, com 99% dos casos abaixo de 10. Constatou-se que 99,9% das áreas de captação têm superfície inferior a 120 m2, e uma média de 51,9 m2. O volume máximo armazenado na cisterna decresce, evidenciando uma ociosidade da capacidade de reservação de 16 mil litros, o que faz com que o uso de cisternas com essa capacidade deveria ser associado a uma área de telhado compatível com seu volume de armazenamento, sendo mais recomendável que uma ampliação na área de coleta que resultaria em um maior benefício para a família. Cerca de 25% dos casos o volume adequado da cisterna seria inferior a 6 mil litros. O uso de cisternas com volumes diferentes, mais ajustados às situa

Giant cisterna chyli: MRI depiction with gadolinium-DTPA enhancement

International Nuclear Information System (INIS)

Lee, K.C.Y.; Cassar-Pullicino, V.N.

2000-01-01

AIM: To demonstrate the use of MRI with Gadolinium-DTPA enhancement in the diagnosis of giant cisterna chyli. MATERIALS AND METHODS: The study consisted of contrast enhanced MRI with ultrasound and CT correlation in three patients with a giant cisterna chyli. An analysis of the morphology, location and post-contrast MR signal characteristics in relation to time was performed. RESULTS: Cisterna chyli has a characteristic lobulated morphology and location but the unenhanced MRI appearances are not specific. The post-Gadolinium-DTPA MRI appearances are critically dependent on the time elapsed after injection of contrast medium. Within the first 5 min, there is no enhancement at all, but by 10 min there is early layering of contrast medium evident, which by 30 min produces a clear fluid-fluid level. Delayed images at 4-5 h demonstrate a uniform enhancement of the cisternal contents producing a homogeneous intermediate signal. All of these features are best visualized on T1 fast saturation sequences. CONCLUSION: MRI with Gadolinium-DTPA enhancement is valuable in confirming the nature of the lymphatic ducts in the retroperitoneal space and helps to differentiate these normal structures from alternative lesions such as lymphadenopathy and tumour recurrence. Lee, K.C.Y., Cassar-Pullicino, V.N. (2000)

Cerebral Metabolic Changes Related to Oxidative Metabolism in a Model of Bacterial Meningitis Induced by Lipopolysaccharide

DEFF Research Database (Denmark)

Munk, Michael; Rom Poulsen, Frantz; Larsen, Lykke

2018-01-01

BACKGROUND: Cerebral mitochondrial dysfunction is prominent in the pathophysiology of severe bacterial meningitis. In the present study, we hypothesize that the metabolic changes seen after intracisternal lipopolysaccharide (LPS) injection in a piglet model of meningitis is compatible...... with mitochondrial dysfunction and resembles the metabolic patterns seen in patients with bacterial meningitis. METHODS: Eight pigs received LPS injection in cisterna magna, and four pigs received NaCl in cisterna magna as a control. Biochemical variables related to energy metabolism were monitored by intracerebral...... dysfunction with increasing cerebral LPR due to increased lactate and normal pyruvate, PbtO2, and ICP. The metabolic pattern resembles the one observed in patients with bacterial meningitis. Metabolic monitoring in these patients is feasible to monitor for cerebral metabolic derangements otherwise missed...

Ramon Llull's Ars Magna

DEFF Research Database (Denmark)

Jensen, Thessa

2017-01-01

might be a viable and valuable approach to understand some of the challenges and possibilities found in computer science and ethics. Vita Llull was born in 1232 in Palma de Mallorca, a melting pot for different cul-tures and religions at the time. Being educated at the king’s court, Llull learned...... of belief, life, and God as such. Computer Science? Llull was an inspiration for later scientists, most notably Giordano Bruno, Athanasius Kirchner, Agrippa of Nettesheim and Gottfried Wilhelm Leibniz, whose dissertation De Arte Combinatoria begins with a discussion of Llull’s Ars Magna. Umberto Eco also......-ple of Mallorca have since tried to have Llull canonised as a saint. Ars Magna A few years before his death Llull began to write the most thorough and final version of his Ars Magna, the Ars Generalis Ultima [3]. The books explain the different figures of the Ars, its principles, questions, descriptions...

Genetic homogeneity of Fascioloides magna in Austria.

Science.gov (United States)

Husch, Christian; Sattmann, Helmut; Hörweg, Christoph; Ursprung, Josef; Walochnik, Julia

2017-08-30

The large American liver fluke, Fascioloides magna, is an economically relevant parasite of both domestic and wild ungulates. F. magna was repeatedly introduced into Europe, for the first time already in the 19th century. In Austria, a stable population of F. magna has established in the Danube floodplain forests southeast of Vienna. The aim of this study was to determine the genetic diversity of F. magna in Austria. A total of 26 individuals from various regions within the known area of distribution were investigated for their cytochrome oxidase subunit 1 (cox1) and nicotinamide dehydrogenase subunit 1 (nad1) gene haplotypes. Interestingly, all 26 individuals revealed one and the same haplotype, namely concatenated haplotype Ha5. This indicates a homogenous population of F. magna in Austria and may argue for a single introduction. Alternatively, genetic homogeneity might also be explained by a bottleneck effect and/or genetic drift. Copyright © 2017 Elsevier B.V. All rights reserved.

Cardioactive effects of diphenhydramine and curcumin in Daphnia magna

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Noelle Erin Romero

2009-01-01

Full Text Available Although used as a model for examining the cardioactive effects of various compounds, the neuromuscular regulation of the heart of the crustacean Daphnia magna (D. magna is not well understood. In the present study, we sought to determine how the heart rate of D. magna was affected by two previously untested compounds: curcumin and diphenhydramine (DPHM. DPHM produces a number of cardiotoxic side effects in vertebrates, particularly sinus tachycardia. Curcumin acts as a monoamine oxidase inhibitor (MAOI and was expected toincrease the heart rate of D. magna. DPHM was found unexpectedly to lower the heart rate of D. magna with time. Curcumin increased heart rate when administered in higher concentrations. However, co-administration of curcumin with DPHM negated this effect. These findings may be explained by the potential role of histamine as a sympathetic cardiac neurotransmitter in D. magna.

Ecotoxicity tests based on phototactic behaviour in Daphnia magna; Saggi di ecotossicita` con Daphnia magna basati sul comportamento fototattico

Energy Technology Data Exchange (ETDEWEB)

Dojmi di Delupis, Gianluigi [Istituto Superiore di Sanita`, Rome (Italy). Lab. di Tossicologia Comparata ed Ecotossicologia

1997-03-01

Zooplankton behaviour depending on light, such as phototaxis, is important, mainly in terms of its ecological significance, as, for example, in the role of phototaxis in the diurnal vertical migration of Daphnia magna, and its possible involvement in predator-prey relations. In Daphnia magna chemicals were found to induce roughly three types of phototaxis alteration: depression, enhancement and sign change. These phenomena are based on mechanisms that require further investigation. In spite of the complex photobehaviour of Daphnia magna and the scarce knowledge of toxic effects, it was possible to set up rapid and easy ecotoxicity tests by fixing certain experimental conditions.

Blood Profile of Rabbits Infected with Eimeria magna

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A Hana

2011-09-01

Full Text Available Abstract. The research aimed at determining the blood profile of local rabbits infected with different dose of Eimeria magna oocysts. This research used 45 male rabbits with the age of 4 month old, range from 1.5 to 1.8 kg, clinically healthy and free from coccidiosis. The rabbits were randomly divided into 3 groups, group I as control (K-0 was given 1.0 ml distilled water/rabbit orally, group II (K-10 was infected with single dose of 10x106 oocysts of E. magna/rabbit orally, and group III (K-20 was infected with single dose of 20x106 oocysts of E. magna/rabbit orally. After infection, rabbits were examined for clinical signs, body weight and temperature daily for five days. Blood samples were drawn from the vena marginalis to examine the number of erythrocytes, hemoglobine, packed cell volume (PCV, leukocytes and its deferent, total protein plasma (TPP and fibrinogen, activities of alkaline phosphatase (ALP, alanine amino transferase (ALT, and aspartat aminotransferase (AST. The data were statistically analyzed by two-way anova using factorial design. The results of this research showed that the infection of E. magna in rabbits caused fever and weight loss, accompanied by normochromic microcytic anemia (at doses of 10x106 oocysts, macrocytic normochromic (at doses of 20x106 oocysts, leukocytosis, lymphocytosis, hiperfibrinogenemia, and increased of ALP activity. There were correlations between clinical symptoms and blood profile of rabbits infected with E. magna for five days. The higher the dose and the longer the infection of E. magna in rabbits caused weight loss, increased body temperature, MCV (microcytic to macrocytic, leukocyte, fibrinogen and ALP activity. These findings were useful to have a better understanding of pathophysiology of E. magna infection in  rabbits. Key Words: Eimeria magna, oocyst, rabbit, blood profile A Hana et al/Animal Production 13(3:185-190 (2011

Live-cell imaging of dual-labeled Golgi stacks in tobacco BY-2 cells reveals similar behaviors for different cisternae during movement and brefeldin A treatment.

Science.gov (United States)

Madison, Stephanie L; Nebenführ, Andreas

2011-09-01

In plant cells, the Golgi apparatus consists of numerous stacks that, in turn, are composed of several flattened cisternae with a clear cis-to-trans polarity. During normal functioning within living cells, this unusual organelle displays a wide range of dynamic behaviors such as whole stack motility, constant membrane flux through the cisternae, and Golgi enzyme recycling through the ER. In order to further investigate various aspects of Golgi stack dynamics and integrity, we co-expressed pairs of established Golgi markers in tobacco BY-2 cells to distinguish sub-compartments of the Golgi during monensin treatments, movement, and brefeldin A (BFA)-induced disassembly. A combination of cis and trans markers revealed that Golgi stacks remain intact as they move through the cytoplasm. The Golgi stack orientation during these movements showed a slight preference for the cis side moving ahead, but trans cisternae were also found at the leading edge. During BFA treatments, the different sub-compartments of about half of the observed stacks fused with the ER sequentially; however, no consistent order could be detected. In contrast, the ionophore monensin resulted in swelling of trans cisternae while medial and particularly cis cisternae were mostly unaffected. Our results thus demonstrate a remarkable equivalence of the different cisternae with respect to movement and BFA-induced fusion with the ER. In addition, we propose that a combination of dual-label fluorescence microscopy and drug treatments can provide a simple alternative approach to the determination of protein localization to specific Golgi sub-compartments.

Bioaccumulation and uptake routes of perfluoroalkyl acids in Daphnia magna.

Science.gov (United States)

Dai, Zhineng; Xia, Xinghui; Guo, Jia; Jiang, Xiaoman

2013-02-01

Perfluoroalkyl acids (PFAs), one kind of emerging contaminants, have attracted great attentions in recent years. However, the study about their bioaccumulation mechanism remains scarce. In this research, the bioaccumulation of six kinds of PFAs in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338 L kg(-1) d(-1), and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82 d(-1). The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380 L kg(-1) in wet weight after 25 d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the n-octanol/water partition coefficients (logK(ow)) of PFAs (pPFAs plays an important role in their bioaccumulation. The BAFs almost kept constant when the PFA concentrations in aqueous phase increased from 1 to 10 μg L(-1). Scenedesmus subspicatus, as the food of D. magna, did not significantly affect the bioaccumulation of PFAs by D. magna. Furthermore, the body burden of PFAs in the dead D. magna was 1.08-2.52 times higher than that in the living ones, inferring that the body surface sorption is a main uptake route of PFAs in D. magna. This study suggested that the bioaccumulation of PFAs in D. magna is mainly controlled by their partition between organisms and water; further research should be conducted to study the intrinsic mechanisms, especially the roles of protein and lipid in organisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

Aircushion Supported Mega-Floaters

NARCIS (Netherlands)

Van Kessel, J.L.F.

2010-01-01

The increase of the global population and expanding coastal mega-cities will necessitate an innovative pursuit of the utilization of the ocean space in which mega-floaters will play an important role in the future. These types of structures are very large floating artificial islands that can be used

magna (Straus, 1820.

Directory of Open Access Journals (Sweden)

Hatice Parlak

2015-12-01

Full Text Available Nif Çayi Kirletilmiş Tatli Su ve Sedimentinin Daphnia magna (Strauss, 1820 Üzerine Akut Ve Kronik Toksisitesi. Nif Çayı Endüstriyel, evsel ve tarımsal deşarjlar ile doğrudan kirlenmektedir. Çayın suyunun evsel ve endüstriyel alanlarda sulama ve yıkama suyu olarak kullanılması rahatsızlık verici boyuttadır, bu nedenle doğal populasyonlar için potansiyel toksisitesinin bilinmesi büyük öneme sahiptir. Bu çalışmanın amacı Nif Çayı su ve sediment örneklerinin su piresi Daphnia magna kullanılarak toksisitesinin belirlenmesidir. Su ve sediment örneklerinin letal toksisitesi 48-saat akut test, subletal toksisite ise 7-gün kronik test ile gerçekleştirilmiştir. D.magna kullanılarak yapılan 48 saat Akut test sonuçlarına göre LC 50 değerleri su örnekleri için 6.8 ile 12.67 µl/L arasında sediment örnekleri içn 6.826 ile 38.038 µg/L arasında bulunmuştur. Subletal konsantrasyonlara maruz bırakılarak yapılan kronik testler sonucunda tüm istasyonlardan alınan su ve sediment örneklerin canlının üremesi üzerine negatif etkisi olduğu gözlenmiştir. Elde edilen veriler ışığında bu deneme sisteminin rutin kirlilik belirleme çalışmaları için uygunluğu tespit edilmiştir

Case of pacemaker pocket infection caused by Finegoldia magna.

Science.gov (United States)

Hosseini Dehkordi, Seyed Hamed; Osorio, Georgina

2017-10-01

Finegoldia magna (formerly called Peptostreptococcus magnus) is a Gram-positive anaerobic coccus which is increasingly recognized as an opportunistic pathogen. We present a case of F. magna associated non-valvular cardiovascular device-related infection in an 83 year-old male who received a permanent pacemaker for sick sinus syndrome seven weeks prior to his presentation. Five weeks after the implantation, the pacemaker and leads were explanted because of clinical evidence of pacemaker pocket infection. He was initially treated with sulfamethoxazole-trimethoprim based on the Gram stain results from the removed pacemaker. However, two weeks later, he was readmitted with sepsis and was successfully treated with ampicillin-sulbactam. Culture results from the pacemaker and pocket as well as blood cultures grew F. magna. Clinicians should be aware of the possibility of F. magna infection when initial gram stain results show "gram positive cocci". Copyright © 2017 Elsevier Ltd. All rights reserved.

QUALIDADE MICROBIOLÓGICA DA ÁGUA DE CHUVA ARMAZENADA EM CISTERNAS NA ÁREA RURAL DE INHAMBUPE, NO SEMIÁRIDO BAIANO, E SEUS FATORES INTERVENIENTES

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Nara de Melo Dantas Silva

2014-09-01

Full Text Available Com a existência da problemática de carência hídrica no Semiárido Brasileiro devido aos fatores climáticos e edáficos, o sistema de captação e armazenamento de água de chuva, mostra-se como uma solução para o abastecimento de água, melhorando a qualidade de vida dos habitantes das regiões semiáridas, inclusive dos moradores de Inhambupe. Ao estudar os fatores intervenientes da água de chuva armazenada em cisternas da zona rural do município de Inhambupe, pode-se concluir que existe a possibilidade dos microrganismos, bioindicadores e/ou patogênicos, e a matéria orgânica adentra nas cisternas por meio: da ausência do desvio da primeira água, da não existência de calha de proteção das cisternas, da forma inadequada de retirada de água do interior da cisterna, da existência de árvores próximas à superfície de coleta e da criação de animais, como porcos, galinhas e a presença de curral, ocorrendo a entrada de impurezas, estas podem permanecer no interior da cisterna, caso a família não realize sua limpeza periódica e dos seus componentes. Na avaliação da qualidade microbiológica da água de chuva armazenada nas cisternas estudadas, a maioria das amostras analisadas (78,1% apresentaram coliformes termotolerantes. Com relação a presença de bactérias heterotróficas se faz presente em todas as análises de amostras de água de todas as cisternas estudadas. Aplicando-se o planejamento fatorial para identificar os fatores intervenientes da qualidade microbiológica da água das cisternas, tendo como variável resposta ‘coliformes termotolerantes’, e levando-se em consideração a presença dos fatores analisados a um nível de confiança de 10%, os fatores que apresentaram efeitos significativos foram: Balde*Limpeza*Falta Desvio, Falta Desvio, Árvores, a interação dos quatros fatores estudados - Balde*Limpeza*Árvores*Falta Desvio e Árvores*Falta Desvio. Para a variável resposta bactérias heterotr

MEGA: A Low-Background Radiation Detector

International Nuclear Information System (INIS)

Kazkaz, Kareem; Aalseth, Craig E.; Hossbach, Todd W.; Gehman, Victor M.; Kephart, Jeremy; Miley, Harry S.

2004-01-01

The multiple-element gamma assay (MEGA) is a low-background detector designed to support environmental monitoring and national security applications. MEGA also demonstrates technology needed or Majorana, a next generation neutrino mass experiment. It will also exploit multicoincidence signatures to identify specific radioactive isotopes. MEGA is expected to begin testing in late 2003 for eventual installation at the Waste Isolation Plant, Carlsbad, NM

Aspectos da miocardite em chagásicos crônicos com "megas" e sem "megas" com insuficiência cardíaca congestiva

Directory of Open Access Journals (Sweden)

Hipólito de Oliveira Almeida

1984-06-01

Full Text Available O estudo microscópico de 20 corações de chagásicos com "megas" e de outros 20 sem "megas" com insuficiência cardíaca congestiva (ICC revelou que tanto a Jibrose quanto o exsudato inflamatório no miocárdio são discretos nos casos de "megas" e geralmente acentuados nos casos de ICC. Considerando-se que nos "megas" a ICC, a hipertrofia do miocárdio e a lesão vorticilar são fenômenos raros, nossos achados (atuais e anteriores sugerem que estes estejam relacionados principalmente com a agressão inflamatória ao miocárdio ventricular, uma vez que a desnervação é, geralmente, mais acentuada nos casos de "megas" que nos de ICC.The study of 20 hearts from chagasic patients with "megas " and of others 20 from chagasics without "megas" with heart failure, shows that both, myocardial Jibrosis and inflammatory exudate are light in cases with "megas" and severe in group with heart failure. In chagasic with "megas" the myocardial hypertrophy, the apical lesion and the cardiac insufficiency are infrequent. Ourfindings suggest that they are related to the myocardial ventricular inflammation and not to the cardiac denervation. This latter is more severe in cases of "megas" than in cases of congestive heart failure without "megas".

Ramon Llull's Ars Magna

DEFF Research Database (Denmark)

Jensen, Thessa

2018-01-01

The Ars Magna of Ramon Llull must be seen as one of the first attempts to formalise language, thought processes, and creating a basis for rational discussions. It consists of so-called principles, concepts, which are defined and combined through the use of four main figures. Llull's contribution...

THE CENTURY OF MEGA - DAGUOS. THE CHARTER OF PEACEFUL COEXISTENCE AMONG THE MEGA - DAGUOS

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Mădălina Virginia ANTONESCU

2017-11-01

Full Text Available The current paper discusses the origins of the concept of “daguo”, a term used in the Chinese academic literature to refer to the “great powers”. We will use a particular concept, i.e. “mega -daguo”, to refer to entities higher than the great powers (states, in the classic sense, that is new, trans-state or super -state actors of transcontinental or continental dimensions. Such entities create fusions among different civilizations; they have a specific behaviour, distinct from the behaviour of great powers, as currently perceived by us, in the traditional sense of the term. The current paper analyses the typology of mega-daguos; we will refer to the post-Huntingtonian age, that of a world which has overcome the dualist paradigm of the “inevitable conflict” among the civilizations, a world which has turned the principle of dialogue among the mega-daguos into a fundamental principle underlying a world of colossi. The last part of the paper proposes a fundamental document of the new world of post-state actors (mega-daguos, for the 21st century. We will call it the“Charter of peaceful coexistence among the mega-daguos”, with an approach to the issue of reorganizing the UN, in order to be able to come to terms with such reality, in the 21stcentury post-state world based on a global law, in which post - state actors are also legally responsible for their behaviour and their decisions, at global level.

Long-term effects to ionizing radiation in crustacean Daphnia magna

International Nuclear Information System (INIS)

Sarapul'tseva, E.I.

2016-01-01

The results of this study have provided strong evidence for the trans generational effects of parental exposure to ionizing radiation in crustacean Daphnia magna. To establish whether parental irradiation can affect the survival, life span and fertility of directly exposed organisms and their non-exposed offspring, D. magna were given 10, 100, 1000 and 10,000 mGy of acute γ-rays. MTT-assay was first applied for the investigation in vivo of the mechanisms of trans generational low doses effects of radiation and development of stress in Daphnia. Our dates strongly support MTT assay results as a good bio marker of survival and fertility effects at D. magna. (authors)

Temperate and boreal forest mega-fires: characteristics and challenges

Science.gov (United States)

Scott L. Stephens; Neil Burrows; Alexander Buyantuyev; Robert W. Gray; Robert E. Keane; Rick Kubian; Shirong Liu; Francisco Seijo; Lifu Shu; Kevin G. Tolhurst; Jan W. van Wagtendonk

2014-01-01

Mega-fires are often defined according to their size and intensity but are more accurately described by their socioeconomic impacts. Three factors - climate change, fire exclusion, and antecedent disturbance, collectively referred to as the "mega-fire triangle" - likely contribute to today's mega-fires. Some characteristics of mega-fires may emulate...

Toxicity of three strobilurins (kresoxim-methyl, pyraclostrobin, and trifloxystrobin) on Daphnia magna.

Science.gov (United States)

Cui, Feng; Chai, Tingting; Liu, Xiaoxu; Wang, Chengju

2017-01-01

Strobilurins constitute a new class of fungicides that is the most widely used in the world. The present study was conducted to investigate the aquatic toxicity of 3 common strobilurin fungicides (kresoxim-methyl, pyraclostrobin, and trifloxystrobin) to Daphnia magna. The neonate acute immobilization test showed that the 48-h 50% effective concentration (EC50) values of kresoxim-methyl, pyraclostrobin, and trifloxystrobin were 443.3 µg/L, 20.9 µg/L, and 23.0 µg/L, respectively. In addition, the 3 strobilurins significantly induced activity of the important detoxification enzyme glutathione S-transferase (GST) in D. magna, and there was a significant positive relationship between GST activity and immobility of D. magna after acute exposure. The 3 strobilurins showed higher toxicity to D. magna embryos, and the 48-h EC50 were 157.3 µg/L, 3.9 µg/L, and 1.7 µg/L for kresoxim-methyl, pyraclostrobin, and trifloxystrobin, respectively. The 21-d chronic test revealed that the strobilurins could also significantly affect the reproduction, development, and growth of D. magna at sublethal concentrations. The lowest-observed-effect concentrations of kresoxim-methyl, pyraclostrobin, and trifloxystrobin for reproduction were 20 µg/L, 0.15 µg/L, and 0.2 µg/L, respectively, which were close to environmental concentrations. The findings indicate that strobilurin fungicides are very toxic to D. magna and they are sufficient to cause harm to D. magna at environmentally relevant concentrations. Environ Toxicol Chem 2017;36:182-189. © 2016 SETAC. © 2016 SETAC.

The analysis of the pathophysiology of syringomyelia by means of magnetic resonance imaging

International Nuclear Information System (INIS)

Abe, Toshiaki

1992-01-01

The pathophysiology of syringomyelia was examined with magnetic resonance imaging (MRI) in 70 patients. According to complications, syringomyelia was classified as being associated with (1) Chiari malformation, (2) both Chiari malformation and basal arachnoiditis, (3) basal arachnoiditis, (4) an obstruction of the foramen Magendie, and (5) spinal arachnoiditis. MRI features in Type 1 included: wedge-shaped herniated tonsils with the cisterna magna, pencil-shaped rostral end of the intraspinal syrinx, and obliterated caudal part of the fourth ventricle. These findings suggested that the herniated tonsils might result in the disturbance of cerebro-spinal fluid (CSF) circulation. In Type 2, the tip of the herniated tonsils was round; a triangular space was noted between the herniated tonsils and the upper spinal cord; the rostral end of the intraspinal syrinx was round; and the caudal part of the fourth ventricle was well visualized. These findings revealed that the brain stem and spinal cord were less pressed, suggesting that CSF circulatory disturbance resulted from basal arachnoiditis around the foramen magnum. In Type 3, the cisterna magna was narrowed by a thickened arachnoid membrane. In type 4, the intraspinal syrinx was directly connected with the fourth ventricle via the patent central canal associated with hydrocephalus. The position of the cerebellar tonsils and the size of the cisterna magna were both normal. In Type 5, a partial adhesion of the arachnoid membrane around the spinal cord was shown, and the syrinx was found extended toward the rostral as well as the caudal direction of the arachnoid adhesion. The rostral end of the syrinx was sometimes changed in size during MRI examinatin. This phenomenon sustained William's theory of 'suck and slosh mechanism' of intraspinal syrinx extension. (N.K.)

Magna-field irradiation: physical considerations

Energy Technology Data Exchange (ETDEWEB)

Van Dyk, J.

1983-12-01

Magna-field radiotherapy in the form of total body, half body and total nodal irradiation is becoming increasingly prominent and involves dosimetric problems that are much more pronounced than they are for conventional field sizes. In this review of the physical considerations of magna-field irradiation, a number of possible alternate methods of producing large radiation fields are outlined, the basic beam dosimetry is reviewed and the factors producing dose variation in the patient are considered. Since the lung contains large regions of low density tissues and has a lower tolerance to radiaiton than most other tissues, special consideration is given to methods of dose determination and dose reduction to this organ. The question of accuracy in dose delivery is briefly discussed and the concept of delivering a radiation dose 'as precisely as readily achievable (APARA), technological and biological factors being taken into account' is introduced.

MEGA X: Molecular Evolutionary Genetics Analysis across Computing Platforms.

Science.gov (United States)

Kumar, Sudhir; Stecher, Glen; Li, Michael; Knyaz, Christina; Tamura, Koichiro

2018-06-01

The Molecular Evolutionary Genetics Analysis (Mega) software implements many analytical methods and tools for phylogenomics and phylomedicine. Here, we report a transformation of Mega to enable cross-platform use on Microsoft Windows and Linux operating systems. Mega X does not require virtualization or emulation software and provides a uniform user experience across platforms. Mega X has additionally been upgraded to use multiple computing cores for many molecular evolutionary analyses. Mega X is available in two interfaces (graphical and command line) and can be downloaded from www.megasoftware.net free of charge.

Fossa navicularis magna detection on cone-beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Syed, Ali Z. [Dept. of Oral and Maxillofacial Medicine and Diagnostic Sciences, School of Dental Medicine, Case Western Reserve University, Cleveland(United States); Mupparapu, Mel [Div. of Radiology, University of Pennsylvania School of Dental Medicine, Philadelphia (United States)

2016-03-15

Herein, we report and discuss the detection of fossa navicularis magna, a close radiographic anatomic variant of canalis basilaris medianus of the basiocciput, as an incidental finding in cone-beam computed tomography (CBCT) imaging. The CBCT data of the patients in question were referred for the evaluation of implant sites and to rule out pathology in the maxilla and mandible. CBCT analysis showed osseous, notch-like defects on the inferior aspect of the clivus in all four cases. The appearance of fossa navicularis magna varied among the cases. In some, it was completely within the basiocciput and mimicked a small rounded, corticated, lytic defect, whereas it appeared as a notch in others. Fossa navicularis magna is an anatomical variant that occurs on the inferior aspect of the clivus. The pertinent literature on the anatomical variations occurring in this region was reviewed.

Interspecific differences between D. pulex and D. magna in tolerance to cyanobacteria with protease inhibitors.

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Christian J Kuster

Full Text Available It is known that cyanobacteria negatively affect herbivores due to their production of toxins such as protease inhibitors. In the present study we investigated potential interspecific differences between two major herbivores, Daphnia magna and Daphnia pulex, in terms of their tolerance to cyanobacteria with protease inhibitors. Seven clones each of D. magna and of D. pulex were isolated from different habitats in Europe and North America. To test for interspecific differences in the daphnids' tolerance to cyanobacteria, their somatic and population growth rates were determined for each D. magna and D. pulex clone after exposure to varying concentrations of two Microcystis aeruginosa strains. The M. aeruginosa strains NIVA and PCC(- contained either chymotrypsin or trypsin inhibitors, but no microcystins. Mean somatic and population growth rates on a diet with 20% NIVA were significantly more reduced in D. pulex than in D. magna. On a diet with 10% PCC(-, the population growth of D. pulex was significantly more reduced than that of D. magna. This indicates that D. magna is more tolerant to cyanobacteria with protease inhibitors than D. pulex. The reduction of growth rates was possibly caused by an interference of cyanobacterial inhibitors with proteases in the gut of Daphnia, as many other conceivable factors, which might have been able to explain the reduced growth, could be excluded as causal factors. Protease assays revealed that the sensitivities of chymotrypsins and trypsins to cyanobacterial protease inhibitors did not differ between D. magna and D. pulex. However, D. magna exhibited a 2.3-fold higher specific chymotrypsin activity than D. pulex, which explains the observed higher tolerance to cyanobacterial protease inhibitors of D. magna. The present study suggests that D. magna may control the development of cyanobacterial blooms more efficiently than D. pulex due to differences in their tolerance to cyanobacteria with protease

Absceso mamario no puerperal por Finegoldia magna Nonpuerperal breast abscess caused by Finegoldia magna

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L. Castello

2007-06-01

Full Text Available Finegoldia magna son cocos gram-positivos anaerobios estrictos, cuyas células se disponen en pares, tétradas y acúmulos. Forman parte de la flora normal de la piel, tractos gastrointestinal y genitourinario femeninos, y cavidad oral. La especie se caracteriza por ser asacarolítica y su principal fuente de energía la constituyen aminoácidos y peptonas. Por lo general se la aísla en cultivos polimicrobianos a partir de abscesos y otras infecciones de piel y partes blandas, huesos y articulaciones. En el caso descrito, F. magna fue recuperada en cultivo monomicrobiano, a partir de un absceso mamario no puerperal, que se agrega a los dos casos comunicados en la literatura. La identificación se realizó mediante la determinación de la sensibilidad a los discos de potencia especial, pruebas convencionales, y producción de enzimas sacarolíticas y proteol��ticas. Se efectuó la prueba de sensibilidad a los antimicrobianos por el método epsilométrico. Los agentes ensayados y los valores de CIM (µg/ml obtenidos fueron: penicilina, 0,064; cefalotina, 1; metronidazol, 0,25; minociclina, Finegoldia magna is a species of strictly anaerobic gram-positive cocci, arranged in pairs, tetrads, and clusters. These organisms are components of the normal flora of the skin, gastrointestinal and genitourinary female tracts, and oral cavity. They are asaccharolytic and their major energy sources are aminoacids and peptones. The species is usually isolated in polymicrobial cultures from abscesses, soft tissue infections, bone and joints. In the case herein presented, F. magna was recovered in pure culture from a nonpuerperal breast abscess, which adds to the two reported cases in related literature. Species identification was performed by special potency disks, standard bacteriological anaerobic tests, and production of saccharolytic and proteolytic enzymes. Antimicrobial susceptibility testing was performed by using the epsilometric test. The agents

Estudio de la calidad del agua en cisternas de captación de agua de lluvia en escuelas rurales de Alagoas (Brasil)

OpenAIRE

Gonzalez Abelleira, Mafalda

2014-01-01

El presente trabajo se centra en el estudio de la calidad del agua de Sistemas de Recogida de agua de lluvia en escuelas del Semiárido Alagoano de Brasil. Aspectos de la obra civil también son incluidos. Los Sistemas principalmente están formados por un área de captación de agua de lluvia, cisternas de placas de cemento, canalizaciones que las unen y una bomba manual para la retirada del agua de la cisterna. Se analizaron 206 muestras de parámetros básicos de la calidad del agua – conducti...

Accumulation of dieldrin in an alga (Scenedesmus obliquus), Daphnia magna, and the guppy (Poecilia reticulata)

Science.gov (United States)

Reinert, Robert E.

1972-01-01

Scenedesmus obliquus, Daphnia magna, and Poecilia reticulata accumulated dieldrin directly from water; average concentration factors (concentration in organism, dry weight, divided by concentration in water) were 1282 for the alga, 13,954 for D. magna, and 49,307 (estimated) for the guppy. The amount accumulated by each species at equilibrium (after about 1.5, 3-4, and 18 days, respectively) was directly proportional to the concentration of dieldrin in the water. Daphnia magna and guppies accumulated more dieldrin from water than from food that had been exposed to similar concentrations in water. When guppies were fed equal daily rations of D. magna containing different concentrations of insecticide, the amounts of dieldrin accumulated by the fish were directly proportional to the concentration in D. magna; when two lots of guppies were fed different quantities of D. magna (10 and 20 organisms per day) containing identical concentrations of dieldrin, however, the amounts accumulated did not differ substantially.

In-vitro antioxidant activity of crataeva magna lour. dc bark extract

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Sridhar N

2012-10-01

Full Text Available The plant Crataeva magna belonging to family Capparaceae is used in anti spasmodic, hypotensive, anti-inflammatory, hypoglycemic, anti protozoal, analgesic purposes. The present study was carried out to evaluate appropriate animal model. The antioxidative potential of different solvent extracts of Crataeva magna were evaluated using 1,1-Diphenyl-2-Picrylhydrazyl (DPPH, 2,2 ’-Azino-Bis(3-ethylbenzthiazoline-6-Sulphonic acid (ABTS, superoxide radical, hydroxyl radical, nitric oxide radical scavenging activities and lipid peroxidation inhibition assay. Among those solvent extracts, ethanolic extract of C. magna exhibited highest level of antioxidant activities. The ethanolic extract also inhibited H 2O2 mediated haemolysis and lipid peroxidation in human RBC.

The complete mitochondrial genome sequence of Eimeria magna (Apicomplexa: Coccidia).

Science.gov (United States)

Tian, Si-Qin; Cui, Ping; Fang, Su-Fang; Liu, Guo-Hua; Wang, Chun-Ren; Zhu, Xing-Quan

2015-01-01

In the present study, we determined the complete mitochondrial DNA (mtDNA) sequence of Eimeria magna from rabbits for the first time, and compared its gene contents and genome organizations with that of seven Eimeria spp. from domestic chickens. The size of the complete mt genome sequence of E. magna is 6249 bp, which consists of 3 protein-coding genes (cytb, cox1 and cox3), 12 gene fragments for the large subunit (LSU) rRNA, and 7 gene fragments for the small subunit (SSU) rRNA, without transfer RNA genes, in accordance with that of Eimeria spp. from chickens. The putative direction of translation for three genes (cytb, cox1 and cox3) was the same as those of Eimeria species from domestic chickens. The content of A + T is 65.16% for E. magna mt genome (29.73% A, 35.43% T, 17.09 G and 17.75% C). The E. magna mt genome sequence provides novel mtDNA markers for studying the molecular epidemiology and population genetics of Eimeria spp. and has implications for the molecular diagnosis and control of rabbit coccidiosis.

Medical-biological aspects of radiation effects in Daphnia magna

International Nuclear Information System (INIS)

Sarapultseva, E; Ustenko, K; Uskalova, D; Savina, N

2017-01-01

We have shown that γ-irradiation at doses of 100 and 1000 mGy significantly compromised fecundity and reproductive success of the directly exposed D. magna . These effects were also observed among the non-exposed first-generation progeny of irradiated parents, thus implying the manifestation of transgenerational effects in Daphnia . We have also shown that compromised viability of irradiated D. magna can be attributed cytotoxic effects of irradiation. It would therefore appear that the compromised viability may be attributed to the cytotoxic effects resulted from epigenetic changes affecting some metabolic pathways involved in detoxification of free-radicals. Additionally we have analyzed more distant progeny of irradiated at doses of 10, 100 and 1000 mGy Daphnia . Our data demonstrated that multicellular crustacean D. magna represent a very useful experimental model for analyse of long-term effects of ionising radiation at the organismal level. (paper)

Multigenerational cadmium acclimation and biokinetics in Daphnia magna

International Nuclear Information System (INIS)

Guan Rui; Wang Wenxiong

2006-01-01

A Cd exposure (3 μg L -1 ) experiment was conducted for six successive generations to investigate the responses to chronic Cd stress in Daphnia magna. We observed a biphasic accumulation of Cd in the six generations and suggested a similar pattern with respect to daphnids' tolerance. Cd assimilation efficiencies, daphnid growth, and reproduction corresponded to the changes of tolerance, which was partially accounted for by metallothionein induction. When maternally exposed neonates grew in Cd-free water for one or two generations, their growth, MT concentration and biokinetic parameters partially or totally recovered. The rapid recovery suggests the high potential for ecological restoration from Cd pollution. Our results indicate that the tolerance of sensitive D. magna clones to Cd was dependent on long-term or multigenerational exposure. The tolerance developed within the first several generations might not be maintained, and the animals may become even more sensitive to Cd stress in subsequent generations. - Tolerance of sensitive Daphnia magna clones to cadmium was dependent on long-term or multigenerational exposure

Effect of an Aspartame-Ethanol Mixture on Daphnia magna Cardiac Activity

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Rebecca Kohn

2009-01-01

Full Text Available Aspartame in conjunction with alcohol has been shown to increase the blood alcohol level in humans faster than alcohol and sucrose (Wu et al., 2006. To determine the potential effects of various mixtures of ethanol and aspartame on the nervous system, the heart rate of Daphnia magna (D.magna, water flea was measured in deionized water (control, ethanol, aspartame, and five different mixtures of ethanol and aspartame. The heart rate was chosen as a representative measure since it is controlled by the nervous system and the heart rate of D.magna can easily be measured. The results were statistically evaluated by student’s t-test. A significant increase in heart rate was observed for all mixed assays compared to both control and ethanol, but not to aspartame. The data suggests that the aspartame and alcohol mixture have a greater effect on D. magna heart rate than water or ethanol, but not aspartame alone. We propose that alcohol in combination with aspartame has potentially detrimental consequences for the nervous system.

Aspectos da miocardite em chagásicos crônicos com "megas" e sem "megas" com insuficiência cardíaca congestiva

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Hipólito de Oliveira Almeida

1984-06-01

Full Text Available O estudo microscópico de 20 corações de chagásicos com "megas" e de outros 20 sem "megas" com insuficiência cardíaca congestiva (ICC revelou que tanto a Jibrose quanto o exsudato inflamatório no miocárdio são discretos nos casos de "megas" e geralmente acentuados nos casos de ICC. Considerando-se que nos "megas" a ICC, a hipertrofia do miocárdio e a lesão vorticilar são fenômenos raros, nossos achados (atuais e anteriores sugerem que estes estejam relacionados principalmente com a agressão inflamatória ao miocárdio ventricular, uma vez que a desnervação é, geralmente, mais acentuada nos casos de "megas" que nos de ICC.

GESTÃO HÍDRICA A PARTIR DE CISTERNAS DE PLACAS: AVALIAÇÃO SOCIOAMBIENTAL DA EFICIÊNCIA DO P1MC NO MUNICÍPIO DE PEDRA LAVRADA-PB

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José Adailton Silva

2014-08-01

Full Text Available Atualmente, muitas populações rurais do Semiárido brasileiro têm convivido com árduas realidades em virtude da carência de água. Diante disto, as cisternas de placas surgem como mecanismo para prover o acesso e disponibilidade de água. Neste sentido, a Articulação do Semiárido (ASA elaborou o “Programa Um Milhão de Cisternas Rurais – P1MC”, o qual busca prover o gerenciamento e a valorização da água para a “convivência sustentável” com a escassez de água no Semiárido brasileiro. Conhecendo-se as premissas do P1MC, o presente estudo objetivou analisar a eficiência das cisternas de placas e o desempenho do P1MC para com a disponibilidade de água, e a melhoria da qualidade de vida das famílias que convivem com a escassez hídrica. Para tanto, foram realizados: i estudos sobre a pluviometria (série de 61 anos de precipitação pluvial; ii estimativa do Volume Potencial de Captação (VPC dos telhados residenciais e das cisternas; e iii aplicação de questionários semiestruturados a 40 famílias beneficiadas pelo P1MC, no município de Pedra Lavrada – PB. Como resultados, concluiu-se que: 1 as cisternas de placa é uma tecnologia eficiente e capaz de suprir as necessidades hídricas durante o período de estiagem (8 meses; 2 o P1MC apresentou pontos negativos: ausência de fiscalização das cisternas com problemas (rachaduras e vazamentos, e a impossibilidade de atender aos anseios familiares (dessedentação animal ou cultivo de pequenas lavouras; e 3 o P1MC promoveu o acesso/disponibilidade de água, e “independência hídrica”, promovendo assim a sustentabilidade das famílias rurais em meio às adversidades edafoclimáticas do Semiárido brasileiro.

Multigenerational contaminant exposures produce non-monotonic, transgenerational responses in Daphnia magna

International Nuclear Information System (INIS)

Kimberly, David A.; Salice, Christopher J.

2015-01-01

Generally, ecotoxicologists rely on short-term tests that assume populations to be static. Conversely, natural populations may be exposed to the same stressors for many generations, which can alter tolerance to the same (or other) stressors. The objective of this study was to improve our understanding of how multigenerational stressors alter life history traits and stressor tolerance. After continuously exposing Daphnia magna to cadmium for 120 days, we assessed life history traits and conducted a challenge at higher temperature and cadmium concentrations. Predictably, individuals exposed to cadmium showed an overall decrease in reproductive output compared to controls. Interestingly, control D. magna were the most cadmium tolerant to novel cadmium, followed by those exposed to high cadmium. Our data suggest that long-term exposure to cadmium alter tolerance traits in a non-monotonic way. Because we observed effects after one-generation removal from cadmium, transgenerational effects may be possible as a result of multigenerational exposure. - Highlights: • Daphnia magna exposed to cadmium for 120 days. • D. magna exposed to cadmium had decreased reproductive output. • Control D. magna were most cadmium tolerant to novel cadmium stress. • Long-term exposure to cadmium alter tolerance traits in a non-monotonic way. • Transgenerational effects observed as a result of multigenerational exposure. - Adverse effects of long-term cadmium exposure persist into cadmium free conditions, as seen by non-monotonic responses when exposed to novel stress one generation removed.

Aspectos da miocardite em chagásicos crônicos com "megas" e sem "megas" com insuficiência cardíaca congestiva

OpenAIRE

Almeida,Hipólito de Oliveira; Gobbi,Helenice; Teixeira,Vicente de Paula Antunes; Araújo,Waldir Ferreira; Fernandes,Paula Ávila

1984-01-01

O estudo microscópico de 20 corações de chagásicos com "megas" e de outros 20 sem "megas" com insuficiência cardíaca congestiva (ICC) revelou que tanto a Jibrose quanto o exsudato inflamatório no miocárdio são discretos nos casos de "megas" e geralmente acentuados nos casos de ICC. Considerando-se que nos "megas" a ICC, a hipertrofia do miocárdio e a lesão vorticilar são fenômenos raros, nossos achados (atuais e anteriores) sugerem que estes estejam relacionados principalmente com a agressão ...

A morphometric CT study of Down's syndrome showing small posterior fossa and calcification of basal ganglia

International Nuclear Information System (INIS)

Ieshima, A.; Yoshino, K.; Takashima, S.; Takeshita, K.; Kisa, T.

1984-01-01

We report characteristic and morphometric changes of cranial computed tomography (CT) with increasing age in 56 patients with Down's syndrome aged from 0 month to 37 years. Patients were compared with 142 normal controls aged 0 to 59 years. Width of ventricles, Sylvian fissures, posterior fossa, pons and cisterna magna were measured on CT. The incidences of the cavum septi pellucidi, cavum vergae and cavum veli interpositi and high density in the basal ganglia were examined. There was high incidence (10.7%) of bilateral calcification of basal ganglia in Down's syndrome, although that of pineal body and choroid plexus calcification was similar in Down's syndrome and controls. Basal ganglia calcification is more frequently seen in young Down's syndrome and may be related to the premature aging characteristic of Down's syndrome. The CT in Down's syndrome showed relatively small posterior fossa, small cerebellum, small brain stem and relatively large Sylvian fissures in those under one year of age. There was a high frequency of midline cava and large cisterna magna. There were no significant atrophic changes on CT except after the fifth decade comparing with controls. (orig.)

Transmission risk assessment of invasive fluke Fascioloides magna using GIS-modelling and multicriteria analysis methods

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Juhásová L.

2017-06-01

Full Text Available The combination of multicriteria analysis (MCA, particularly analytic hierarchy process (AHP and geographic information system (GIS were applied for transmission risk assessment of Fascioloides magna (Trematoda; Fasciolidae in south-western Slovakia. Based on the details on F. magna life cycle, the following risk factors (RF of parasite transmission were determined: intermediate (RFIH and final hosts (RFFH (biological factors, annual precipitation (RFAP, land use (RFLU, flooded area (RFFA, and annual mean air temperature (RFAT (environmental factors. Two types of risk analyses were modelled: (1 potential risk analysis was focused on the determination of the potential risk of parasite transmission into novel territories (data on F. magna occurrence were excluded; (2 actual risk analysis considered also the summary data on F. magna occurrence in the model region (risk factor parasite occurrence RFPO included in the analysis. The results of the potential risk analysis provided novel distribution pattern and revealed new geographical area as the potential risk zone of F. magna occurrence. Although the actual risk analysis revealed all four risk zones of F. magna transmission (acceptable, moderate, undesirable and unacceptable, its outputs were significantly affected by the data on parasite occurrence what reduced the informative value of the actual transmission risk assessment.

CRISPR/Cas-mediated targeted mutagenesis in Daphnia magna.

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Takashi Nakanishi

Full Text Available The water flea Daphnia magna has been used as an animal model in ecology, evolution, and environmental sciences. Thanks to the recent progress in Daphnia genomics, genetic information such as the draft genome sequence and expressed sequence tags (ESTs is now available. To investigate the relationship between phenotypes and the available genetic information about Daphnia, some gene manipulation methods have been developed. However, a technique to induce targeted mutagenesis into Daphnia genome remains elusive. To overcome this problem, we focused on an emerging genome editing technique mediated by the clustered regularly interspaced short palindromic repeats/CRISPR-associated (CRISPR/Cas system to introduce genomic mutations. In this study, we targeted a functionally conserved regulator of eye development, the eyeless gene in D. magna. When we injected Cas9 mRNAs and eyeless-targeting guide RNAs into eggs, 18-47% of the survived juveniles exhibited abnormal eye morphology. After maturation, up to 8.2% of the adults produced progenies with deformed eyes, which carried mutations in the eyeless loci. These results showed that CRISPR/Cas system could introduce heritable mutations into the endogenous eyeless gene in D. magna. This is the first report of a targeted gene knockout technique in Daphnia and will be useful in uncovering Daphnia gene functions.

Marrow stromal cells administrated intracisternally to rats after traumatic brain injury migrate into the brain and improve neurological function

Institute of Scientific and Technical Information of China (English)

胡德志; 周良辅; 朱剑虹

2004-01-01

@@ Marrow stromal cells(MSCs) have been reported to transplant into injured brain via intravenous or intraarterial or direct intracerebral administration.1-3 In the present study, we observed that MSCs migrated into the brain, survived and diffeneriated into neural cells after they were injected into the cisterna magna of rats, and that the behavior of the rats after traumatic brain injury (TBI) was improved.

Cerebellomedullary Cistern Delivery for AAV-Based Gene Therapy: A Technical Note for Nonhuman Primates

OpenAIRE

Samaranch, Lluis; Bringas, John; Pivirotto, Philip; Sebastian, Waldy San; Forsayeth, John; Bankiewicz, Krystof

2015-01-01

Accessing cerebrospinal fluid (CSF) from the craniocervical junction through the posterior atlanto-occipital membrane via cerebellomedullary injection (also known as cisternal puncture or cisterna magna injection) has become a standard procedure in preclinical studies. Such delivery provides broader coverage to the central and peripheral nervous system unlike local parenchymal delivery alone. As a clinical application, this approach offers a more reliable method for neurological gene replacem...

Sistem Keamanan Pintu Berbasis Arduino Mega

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Akbar iskandar

2017-12-01

Full Text Available Abstract  : This study aims is to 1 design prototype security room lecturer room based arduino mega integrated with Fingerprint and camera, 2 Testing the effectiveness of prototype security room door lecturer. This type of research is a type of research design that is within the scope of research R & D (Research and Development. Data were collected based on observations and interviews. Data analysis technique by descriptive method. The result of the research shows that prototype of latchroom room door STMIK AKBA using arduino mega camera and fingerprint can assist lecturers in improving security in lecturers room and based on descriptive analysis result found that the device can run effectively. Abstrak: Penelitian ini bertujuan adalah untuk 1 merancang prototype pengamanan pintu ruang dosen berbasis arduino mega yang terintegrasi dengan Fingerprint dan kamera, 2 Menguji Efektifitas prototype kemanan pintu ruang dosen. Jenis penelitian ini adalah jenis penelitian perancangan yang dalam lingkup penelitian R&D (Penelitian dan Pengembangan. Data dikumpulkan berdasarkan observasi dan wawancara. Teknik analisis data dengan cara deskriptif. Hasil penelitian itu menunjukkan bahwa prototype pengaman pintu ruang dosen STMIK AKBA menggunakan kamera dan fingerprint berbasis arduino mega dapat membantu dosen dalam meningkatkan keamanan pada ruang dosen dan berdasarkan hasil analisis secara deskriptif ditemukan bahwa perangkat tersebut dapat berjalan dengan efektif.

[Ultrasound measurement of fetal posterior fossa at 11 to 13⁺⁶ gestational weeks for screening open spina bifida].

Science.gov (United States)

Qin, Feng-Zhen; Li, Sheng-Li; Wen, Hua-Xuan; Ouyang, Yu-Rong; Zheng, Qiong; Bi, Jing-Ru

2014-06-01

To establish the normal reference ranges of transabdominal ultrasound measurements of the posterior fossa structure in fetuses at 11 to 13⁺⁶ gestational weeks and explore their clinical value in screening open spina bifida (OSB). Between January, 2013 and September, 541 randomly selected normal fetuses underwent nuchal translucency at the gestational age 11 to 13⁺⁶ weeks. The parameters of the posterior fossa were measured in mid-sagittal view of the fetal face and the axial view of the transverse cerebellum insonated through the anterior fontanel by transabdominal ultrasound to establish the normal reference ranges. The measurements were obtained from 3 fetuses with OSB for comparison with the reference ranges. In normal fetuses, the parameters of the posterior fossa measured in the two views showed no significant differences (P>0.05). Two high echogenic lines were observed in normal fetuses, as compared with one in fetuses with OSB representing the posterior border of the brain stem and the anterior border of the fourth ventricle. The line between the posterior border of the fourth ventricle and the anterior border of the cisterna magna was not displayed in fetuses with OSB. The anteroposterior diameters of the brain stem, the fourth ventricle, and cisterna magna all increased in positive correlation with the crown-lump length in normal fetuses. In the 3 OSB fetuses, the anteroposterior diameter of the brain stem exceeded the 95th percentile and the anteroposterior diameter of fourth ventrical-cisterner magena was below the 5th percentile of the reference range for CRL; the brain stem to fourth ventrical-cisterner magena anteroposterior diameter ratio was increased to above 1. The established normal reference ranges of the parameters of fetal posterior fossa may provide assistance in early OSB detection. The absence of the posterior border of the fourth ventricle and the anterior border of the cisterna magna and a brainstem to fourth ventrical

Estudo da viabilidade do uso de cisternas em assentamento rural no município de Várzea-PB

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J. S. Nóbrega

2016-01-01

Full Text Available A escassez hídrica é um dos grandes problemas enfrentados pelas famílias que residem no semiárido nordestino, interferindo diretamente na qualidade de vida das famílias. Diante desse contexto se faz necessário a adoção de técnicas que se constitua uma alternativa viável para a melhoria na convivência das famílias, entre elas, o uso de cisternas para a captação de água da chuva, mostra-se uma alternativa que vem ganhando destaque. Neste sentido este trabalho teve como objetivo avaliar a viabilidade do uso de cisternas na melhoria das condições de vida das famílias do assentamento Novo Horizonte, no município de Várzea – PB. A pesquisa foi realizada no assentamento rural Novo Horizonte, pertencente a zona rural do município de Várzea – PB, onde foram realizados aplicação de questionários a famílias residentes no local. Os questionários eram de natureza quantitativa, uma vez que os mesmos, foram traduzidos em números, opiniões e informações para classifica-los e analisa-los. O questionário era composto por perguntas objetivas e subjetivas, abordando os aspectos de usos da água da cisterna, formas de tratamento da água, importância das cisternas, formas de captação de água, entre outros. Perante os relatos dos entrevistados foi observado que 100% possuíam cisterna em sua casa, e que as mesmas são uma alternativa eficiente para suprir as necessidades das famílias assistidas, sendo considerada uma fonte eficiente na captação de água das chuvas, e assim, proporcionando melhorias nas condições e qualidade de vida dos mesmos.Use of cisterns in the land settlement Novo Horizonte, municipality of Várzea in the state of ParaibaAbstract: Water scarcity is a one great problem faced by families residing in the northeastern semi-arid interfering directly in the his quality of life. In this context it’s necessary to adopt techniques that constitute a viable alternative to improve the coexistence of families

Counseling a Patient with the Antenatal Diagnosis of a Cerebellar Abnormality and a Pharyngeal Cyst

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Lissa Francois

2014-11-01

Full Text Available Introduction - Prenatal counseling with regards to the prognosis of a cerebellar abnormality is hindered not only by the diverse clinical presentations but also by the presence of subtle findings. We present a case of a distinct combination of asymmetric cerebellar hypoplasia secondary to an anterior meningoencephalocele through a clival defect that caused a severe airway obstruction in the newborn. Case Description - A 21-year-old gravida 4 para 0 mother with a dichorionic–diamniotic twin pregnancy was referred for a second trimester sonographic survey. An asymmetric cerebellar hypoplasia, mega cisterna magna, and a pharyngeal cystic mass were noted on twin A. Magnetic resonance imaging report confirmed posterior fossa abnormalities and shed no light on the differential diagnosis of the cystic mass. The pregnancy ended by Cesarean delivery at 32 weeksʼ gestation after a preterm premature rupture of the membranes. Twin A had a severe airway obstruction. Postnatal evaluation confirmed a midline anterior meningoencephalocele through a defect in the clivus. The microarray chromosomal analysis demonstrated a 5q15 variant with uncertain clinical significance. Conclusion - Antenatal recognition of the unique combination of a cerebellar hypoplasia with a pharyngeal cyst can impact the prenatal counseling as well as neonatal management.

Economic Multipliers and Mega-Event Analysis

OpenAIRE

Victor Matheson

2004-01-01

Critics of economic impact studies that purport to show that mega-events such as the Olympics bring large benefits to the communities “lucky” enough to host them frequently cite the use of inappropriate multipliers as a primary reason why these impact studies overstate the true economic gains to the hosts of these events. This brief paper shows in a numerical example how mega-events may lead to inflated multipliers and exaggerated claims of economic benefits.

From Ephemeral Planning to Permanent Urbanism: An Urban Planning Theory of Mega-Events

Directory of Open Access Journals (Sweden)

Eva Kassens-Noor

2016-03-01

Full Text Available Mega-events like the Olympic Games are powerful forces that shape cities. In the wake of mega-events, a variety of positive and negative legacies have remained in host cities. In order to bring some theoretical clarity to debates about legacy creation, I introduce the concepts of the mega-event utopia, dystopia and heterotopia. A mega-event utopia is ideal and imaginary urbanism embracing abstract concepts about economies, socio-political systems, spaces, and societies in the host during events. The mega-event utopia (in contrast to other utopian visions other stakeholders may hold is dictated by the desires of the mega-event owners irrespective of the realities in the event host. In short, a mega-event utopia is the perfect event host from the owner’s perspective. Mega-event utopias are suggested as a theoretical model for the systematic transformation of their host cities. As large-scale events progress as ever more powerful transformers into this century, mega-event dystopias have emerged as negatives of these idealistic utopias. As hybrid post-event landscapes, mega-event heterotopias manifest the temporary mega-event utopia as legacy imprints into the long-term realities in hosting cities. Using the Olympic utopia as an example of a mega-event utopia, I theorize utopian visions around four urban traits: economy, image, infrastructure and society. Through the concept of the mega-event legacy utopia, I also provide some insight toward the operationalization of the four urban traits for a city’s economic development, local place marketing, urban development, and public participation.

MEGAS multi-electrode gas sensor system. Final report; MEGAS - Multi-Elektroden-Gassensorsystem. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Kelleter, J.

2003-07-01

In the context of the MEGAS project, GTE developed and and constructed an electronic system for controlling and data acquisition of sensors for laboratory and test applications. The system is based on microcontrollers and has a data bus connection. Measurements made in order to find out whether the concentrations of a binary gas mixture and combustion gases are detected separately were successful. A demonstration system was constructed. The MEGAS project showed that it is possible to separate two gases by a sensitive layer at constant sensor temperature. The sensor element is a promising technology. Further research is required on suppressing sensor poisoning by siloxanes, and on reduced sensitivity to interfering gases (e.g. ethanol in the case of combustion gases). (orig.)

More Intense Mega Heat Waves in the Warmer World

Science.gov (United States)

Choi, G.; Robinson, D. A.

2017-12-01

In this study, changes in the occurrences of heat waves on the globe since the mid- 20th century and the synoptic characteristics of mega heat waves at regional scales in the warmer climate are examined. The NCEP-NCAR reanalysis surface data show that there have been no obvious linear changes in the heat wave frequencies at the continental scales since the mid-20th century, but amplified interdecadal variations led to unprecedented intense heat waves in the recent decades at the regional scales. Such mega heat waves have been more frequently observed in the poleward subtropical climate belts as well as in the interior region of continents. According to the analyses of upper tropospheric data, the occurrences of more intense mega heat waves since the late 20th century may be associated with the expansion of subtropical high pressures. These results suggest that populous cities near the subtropical climate zones should provide proactive mega heat wave warning systems for residents due to their vulnerability to the sudden attack of human lives harvest by mega heat waves in the warmer 21st century.

A fluorescence-based hydrolytic enzyme activity assay for quantifying toxic effects of Roundup® to Daphnia magna

DEFF Research Database (Denmark)

Ørsted, Michael; Roslev, Peter

2015-01-01

Daphnia magna is a widely used model organism for aquatic toxicity testing. In the present study, we investigated the hydrolytic enzyme activity of D. magna after exposure to toxicant stress. In vivo enzyme activity was quantified using 15 fluorogenic enzyme probes based on 4-methylumbelliferyl...... or 7-amino-4-methylcoumarin. Probing D. magna enzyme activity was evaluated using short-term exposure (24-48 h) to the reference chemical K2Cr2O7, or the herbicide formulation Roundup®. Toxicant induced changes in hydrolytic enzyme activity were compared to changes in mobility (ISO 6341). The results...... showed that hydrolytic enzyme activity was quantifiable as a combination of whole body fluorescence of D. magna, and fluorescence of the surrounding water. Exposure of D. magna to lethal and sublethal concentrations of Roundup® resulted in loss of whole body enzyme activity, and release of cell...

Life history response of Daphnia magna to a mixotrophic golden alga, Poterioochromonas sp., at different food levels

DEFF Research Database (Denmark)

Zhang, Xue; Hu, Hong-Ying; Perlt, Trine Warming

2011-01-01

The toxicity of Poterioochromonas to Daphnia magna was investigated at different food (Scenedesmus acutus) levels. Poterioochromonas alone of 0.4–20 mg C L-1 was not acutely toxic to D. magna, but did not support D. magna growth, either. When fed mixed diets (2 mg C L-1 in total), D. magna...

Cultural Mega-Events as an International, Cultural, and Political Tool

Directory of Open Access Journals (Sweden)

Julia Nikolaeva

2017-12-01

Full Text Available This article is an attempt to offer a conceptual understanding of various kinds of mega-events and to determine their significance as an instrument of the official international cultural policy. The article examines scientific approaches to understanding and classification of mega-events. The case studies focus on such mega-events as international cross-cultural years and cultural forums. The fact that the official foreign policy of¬ten defines and shapes the goals of mega-events proves their value in establishing and promoting a positive international image of the country. Recent Russian experience in organizing cross-cultural years is examined to discuss positive and negative socio-cultural impact.

Cisternas de produção para melhoria da qualidade de vida no Semiárido do estado de Pernambuco

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E. P. Ferreira

2015-10-01

Full Text Available O Semiárido brasileiro requer uma particular atenção, dada à irregularidade das precipitações pluviométricas que ocorrem na região. A cisterna tipo calçadão do programa Uma Terra e Duas Águas – P1+2 assegura melhoria na dieta alimentar das famílias rurais, por permitir a inserção de frutas e hortaliças na alimentação. Com o presente trabalho objetivou-se realizar um levantamento da situação atual do uso das cisternas de produção e suas reais contribuições na melhoria da qualidade de vida de famílias rurais na microrregião do Vale do São Francisco, no Estado de Pernambuco. Foi realizada uma pesquisa exploratória e qualitativa no campo, com comunidades localizadas nos municípios de Petrolina, Afrânio e Dormentes. Pôde-se concluir que a implantação das cisternas do P1+2, tem se constituído em importante instrumento para melhoria da dieta alimentar das famílias, todavia, há necessidade de melhor acompanhamento técnico quanto ao uso racional e eficiente da água da cisterna.Production cisterns to improve the quality of life in the semiarid of the pernamuco stateAbstract: The Brazilian semiarid requires particular attention, because of the irregularity of rainfall affecting the region. The cistern Calçadão type of the program called One Land and Two Waters - P1 + 2 ensures improvement in the diet of rural families by allowing the inclusion of fruit and vegetables in the diet. This paper aims to survey the current state of the use of production cisterns and their real contributions to the improvement of rural households in the micro region of the São Francisco Valley, in the state of Pernambuco. It was done an exploratory and qualitative research in the field, with communities located in the municipalities of Petrolina, Afrânio and Dormentes. It was concluded that the cisterns of the P1 + 2, have become an important tool for improving the diet of families, however, a better technical support is required about

Breast abscess due to Finegoldia magna in a non-puerperal women.

Science.gov (United States)

Cobo, Fernando; Rodríguez-Granger, Javier; Sampedro, Antonio; Navarro-Marí, José María

2017-10-01

Finegoldia magna is a Gram-positive anaerobic coccus involved in a wide variety of infections. We report a unusual case of breast abscess in a non-puerperal patient. A 46-year-old woman presented with pain and a nodular lesion in the left breast. Culture of abscess drainage resulted in isolation of F. magna. Initial treatment with clindamycin was changed to a definitive treatment with amoxicillin-clavulanate for 10 days due to resistance to clindamycin, and improvement of this infection was documented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of the lipid regulator Gemfibrozil in the Cladocera Daphnia magna at different temperatures.

Science.gov (United States)

Salesa, Beatriz; Ferrando, María D; Villarroel, María J; Sancho, Encarna

2017-02-23

In the present study, an ecotoxicological approach to the evaluation of Gemfibrozil (GEM) as an emerging organic pollutant was done. In order to assess its toxicity, tests were conducted using the cladocera Daphnia magna. Experiments were carried out at 22°C and 28°C. EC 50 , feeding behavior, and chronic toxicity tests (21 days) were evaluated in D. magna exposed to GEM as well as cholesterol levels at 21-day chronic exposure. D. magna GEM EC 50 values (24 h) in our experimental conditions were 148.75 and 116.24 mg L -1 at 22°C and 28°C, respectively. Test concentrations of 0.1, 0.5, 1.0, 5.0 and 7.5 mg L -1 were selected for subacute and chronic experiments. Subacute short-term test (feeding study) was assessed after exposure to the toxicant. Filtration and ingestion rates of D. magna exposed animals did not show any significant difference (P > 0.05) with respect to control daphniids neither at 22°C nor at 28°C. Therefore, GEM test concentrations used in the present study did not reduce feeding behavior in D. magna. Temperature increased from 22°C to 28°C, which resulted in a decrease of the daphniids reproductive parameters such as brood size and number of young per female. Other parameters as longevity were not affected. The GEM concentrations used in the chronic test with D. magna did not affect daphniids longevity but some reproductive parameters as number of young per female or brood size were affected. Finally, a significant decreased in cholesterol levels was found in those animals exposed to the highest toxicant concentrations. More studies must be done to determine the possible implications of GEM in aquatic fauna and to derive its possible effects on the environment.

Correlation of MRI and CSF cytology in the diagnosis of medulloblastoma spinal metastases

International Nuclear Information System (INIS)

Harrison, S.K.; Ditchfield, M.R.; Waters, K.

1998-01-01

Background. Medulloblastoma frequently spreads to involve the spinal cord, which significantly reduces patient survival and determines whether chemotherapy is utilised and the dose of irradiation to the neuraxis. Staging is usually achieved by MRI of the spine and/or cytology of CSF, both methods having their limitations. Objective. To determine whether there is a correlation between CSF cytology and the demonstration of spinal metastases by MRI and whether CSF cytology is useful when spinal MRI is equivocal. Materials and methods. All cases of medulloblastoma diagnosed at our hospital between 1992 and 1997 were identified. Of 26 cases, 11 presentations (age range 4 months to 12 years) had both CSF cytology (either from the cisterna magna or lumbar puncture) and spinal MRI. The MR studies were reviewed for the presence of metastases and the CSF cytology for the presence of tumour cells. Results. We found 100 % correlation between MRI and CSF cytology for samples taken by lumbar puncture (four negative and three positive on both investigations). No correlation was demonstrated when CSF samples were taken from the cisterna magna. Conclusions. Our data suggest that lumbar CSF cytology may be useful when the MRI is equivocal for the presence of metastatic involvement of the spine by medulloblastoma. (orig.)

Bioaccumulation, stress, and swimming impairment in Daphnia magna exposed to multiwalled carbon nanotubes, graphene, and graphene oxide.

Science.gov (United States)

Cano, Amanda M; Maul, Jonathan D; Saed, Mohammad; Shah, Smit A; Green, Micah J; Cañas-Carrell, Jaclyn E

2017-08-01

The use of carbon-based nanomaterials (CNMs) such as multiwalled carbon nanotubes (MWCNTs), graphene, and graphene oxide (GO) is increasing across many applications because of their unique and versatile properties. These CNMs may enter the aquatic environment through many pathways, creating the potential for organism exposure. The present study addresses the bioaccumulation and toxicity seen in Daphnia magna exposed to CNMs dispersed in sodium dodecyl benzene sulfonate (SDBS). In study I, D. magna were exposed to varying outer diameters of MWCNTs for 24 h in moderately hard or hard freshwater. Bioaccumulation of MWCNT was found in all treatments, with the highest concentrations (0.53 ± 0.27 μg/g) in D. magna exposed in hard freshwater (p < 0.005). The median lethal concentration (LC50) was determined for D. magna exposed to CNMs in moderately hard and hard freshwater. In study II, D. magna were exposed to CNMs for 72 h in moderately hard freshwater to assess swimming velocity and generation of reactive oxygen species (ROS) detected by dichlorofluorescein fluorescence. An overall decrease was seen in D. magna swimming velocity after exposure to CNMs. The generation of ROS was significantly higher (1.54 ± 0.38 dichlorofluorescein mM/mg dry wt) in D. magna exposed to MWCNTs of smaller outer diameters than in controls after 72 h (p < 0.05). These results suggest that further investigation of CNM toxicity and behavior in the aquatic environment is needed. Environ Toxicol Chem 2017;36:2199-2204. © 2017 SETAC. © 2017 SETAC.

Sistem Informasi Penjualan Berbasis Kinerja pada Proyek Apartemen Mega City Bekasi

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Dyani Ayu Aisyah

2017-12-01

Full Text Available Mega City Apartment Bekasi is an integrated residence with shopping and office center developed by PT. Mega Utama Development. The sales data encountered in the Mega City apartment project is still manualy by using speadsheet application. There has been no centralized data processing with an application support, especially marketing division. The purpose of this study to build a performance-based sales information system at PT. Mega Utama Development. The method used in developing this information system is SDLC. The SDLC model used in the development of this information system is the "Classic Life Cycle" or waterfall model. With the support of performance-based sales information system, the sales process of apartment units in PT. Mega Utama Development becomes more effective and marketing managers can directly control the performance of sales eksekutifs based on performance reports on this information system.

Qualidade microbiológica das águas de chuva em cisternas da área rural do município de Inhambupe, no semiárido baiano e seus fatores intervenientes

Directory of Open Access Journals (Sweden)

Nara de Melo Dantas Da Silva

2015-12-01

Full Text Available No intuito de atender à demanda hídrica das populações rurais do semiárido baiano, o aproveitamento da água de chuva mostra-se como uma alternativa de abastecimento de água. A preocupação relaciona-se à preservação da qualidade microbiológica da água coletada. O objetivo foi caracterizar a qualidade microbiológica da água de chuva armazenada em cisternas localizadas na área rural de Inhambupe-Bahia, e investigar os principais fatores intervenientes da sua qualidade. A metodologia utilizada foi iniciada pelo levantamento de dados sobre as cisternas e o Sistema de Aproveitamento de Água de Chuva (SAAC, seguido por coleta de amostras e análise da qualidade microbiológica de água de chuvas armazenada em cisternas e seus fatores intervenientes, acompanhados da formulação do questionário de observação, do trabalho de campo e, por último, da análise fatorial. Foi identificada a existência de 707 cisternas em funcionamento com as seguintes variáveis: falta de desvio das primeiras águas (6%, utilização de balde para a retirada da água do interior da cisterna (47%, existência de árvores próximas ao telhado (93%, criação de galinhas (70% e a não realização de limpeza do interior da cisterna (36%. A interação dos fatores: utilização de balde com corda para retirada de água, limpeza da cisterna em tempo inadequado e a falta de desvio das primeiras águas com a presença de árvores próximas ao telhado, foram os responsáveis pela geração dos efeitos significativos sobrea variável resposta ‘coliformes termotolerantes’, levando em consideração um nível de confiança de 10%. Para a variável resposta bactérias heterotróficas, foram os fatores “árvores próximas ao telhado” e a interação dos fatores “balde com corda com árvores próximas ao telhado e com falta de desvio das primeiras águas”. Para gerar efeito de melhoria na qualidade microbiológica da água, deve ocorrer de forma correta a

Bioconcentration of the antidepressant fluoxetine and its effects on the physiological and biochemical status in Daphnia magna.

Science.gov (United States)

Ding, Jiannan; Zou, Hua; Liu, Qingqing; Zhang, Shanshan; Mamitiana Razanajatovo, Roger

2017-08-01

The aim of this study was to evaluate the bioconcentration potential of fluoxetine and its biological effects in Daphnia magna. After 48h of waterborne exposure, the bioconcentration of fluoxetine in D. magna was determined to be 460.61 and 174.41Lkg -1 for nominal exposure concentrations of 0.5 and 5µgL -1 , respectively. Moreover, various biological endpoints, including physiological responses (filtration and ingestion rates), enzymatic biomarkers related to neurotoxicity [acetylcholinesterase (AChE)] and antioxidant defense [superoxide dismutase (SOD)], and an oxidative stress damage marker [malondialdehyde (MDA)], were assessed. Fluoxetine exposure increased the filtration rate of daphnia, while the ingestion rate was not obviously modified. AChE activity was significantly inhibited, highlighting the neurotoxicity of fluoxetine on D. magna. However, with some alterations in the SOD activity and MDA content, no obvious oxidative damage was observed in D. magna exposed to fluoxetine at the tested concentrations. These results indicate that fluoxetine can be accumulated and consequently induce physiological and biochemical perturbations in D. magna. Copyright © 2017. Published by Elsevier Inc.

γ radiation dosimetry in Mega rad range using sugar solution

International Nuclear Information System (INIS)

Venkataramani, R.; Mehta, S.K.; Soman, S.D.

1976-01-01

The formation of malonaldehyde under γ irradiation of solid sucrose and aqueous sucrose, fructose and arabinose solutions has been studied in the Mega rad range. Malonaldehyde (MA) concentration was estimated spectrophotometrically after complexing with 2-thio-barbituric acid. The effect of free radical scavengers (KI and N 2 O) on the yield of MA was investigated. Of the systems studied a 5% aqueous sucrose solution gave a proportional response of MA formation with dose in 0.2 to 5 Mega rad range. A 5% aqueous solution of sucrose prepared from sucrose irradiated in solid state also gave a smooth response of MA yield with dose from 8 to 30 Mega rad. The aqueous and solid sucrose systems together can be conveniently used for dosimetry in the range of 0.2 30 Mega rad. (author)

gamma. radiation dosimetry in Mega rad range using sugar solution

Energy Technology Data Exchange (ETDEWEB)

Venkataramani, R; Mehta, S K; Soman, S D [Bhabha Atomic Research Centre, Bombay (India). Health Physics Div.

1976-09-01

The formation of malonaldehyde under ..gamma.. irradiation of solid sucrose and aqueous sucrose, fructose and arabinose solutions has been studied in the Mega rad range. Malonaldehyde (MA) concentration was estimated spectrophotometrically after complexing with 2-thio-barbituric acid. The effect of free radical scavengers (KI and N/sub 2/O) on the yield of MA was investigated. Of the systems studied a 5% aqueous sucrose solution gave a proportional response of MA formation with dose in 0.2 to 5 Mega rad range. A 5% aqueous solution of sucrose prepared from sucrose irradiated in solid state also gave a smooth response of MA yield with dose from 8 to 30 Mega rad. The aqueous and solid sucrose systems together can be conveniently used for dosimetry in the range of 0.2 30 Mega rad.

Further explication of mega-crisis concept and feasible responses

Directory of Open Access Journals (Sweden)

Yen Victor Yew-Cho

2017-01-01

Full Text Available The contemporary world is in an era of mega-crises, caused by a host of physical, economic, political, social, and cultural factors. Through a step-by-step explication of the root concepts of problem, mess, and crisis, a mega-crisis is posited to be a set of interacting crises that are severe in impact, complex in nature, and global in fallout, with no seeming end in sight. Compared to a crisis, a mega-crisis is higher in severity and deeper in complexity. The paper argues for a stakeholder perspective in megacrisis response, as relying on the organizational standpoint is inadequate for reaching long-term resolutions.

The Mega-Terrorism - The Challenge of the Third Millennium

Directory of Open Access Journals (Sweden)

Daniel Andrișan

2011-06-01

Full Text Available The aim of this article is to describe the "new face" of terrorism in the twenty-first centuryindicating the transition to mass destruction weapons (nuclear terrorism, chemical, biological, toethnic-religious terrorism, the occurrence of massive gray area phenomena of terrorism and how thisphenomenon became a strategic weapon. Mega-terrorism has been existing, at a conceptual level,ever since the 70’s, when the experts of this phenomenon tried to find a semantic cover for thesituations that certain organizations, groups or terrorist or extremist sections would get someWeapons of Mass Destruction Systems. Actually, the 11th of September tragedy proves that megaterrorismrepresents the premeditated destruction, the lack of negotiations, of a tactical goal that wasto be accomplished by means of a threat. The mega-terrorism actors do not intend to get themselvesknown to the public, do not require anything, do not see the threat as means or device to reach theirpurpose. The 21 st century mega-terrorism simple logic is materialized in the systemic destroying ofthe enemy, no longer representing a political power or a government, but an entire ‘disobeying’,‘corrupted’, ‘unfaithful’ population indifferent to the mega-terrorist actors’ desires. New dimensionagainst mega-terrorism determines not only a rethinking of how to combat it, but also the realizationof a conceptual legal framework and measures established to materialize the political decision.

Have the “mega-journals” reached the limits to growth?

Directory of Open Access Journals (Sweden)

Bo-Christer Björk

2015-05-01

Full Text Available A “mega-journal” is a new type of scientific journal that publishes freely accessible articles, which have been peer reviewed for scientific trustworthiness, but leaves it to the readers to decide which articles are of interest and importance to them. In the wake of the phenomenal success of PLOS ONE, several other publishers have recently started mega-journals. This article presents the evolution of mega-journals since 2010 in terms of article publication rates. The fastest growth seems to have ebbed out at around 35,000 annual articles for the 14 journals combined. Acceptance rates are in the range of 50–70%, and speed of publication is around 3–5 months. Common features in mega-journals are alternative impact metrics, easy reusability of figures and data, post-publication discussions and portable reviews from other journals.

The MEGA [Muon decays into an Electron and a GAmma ray] hardware trigger system

International Nuclear Information System (INIS)

Szymanski, J.J.; Amann, J.F.; Black, J.K.; Cooper, M.D.; Wright, S.C.; Crocker, J.; Sanders, H.

1988-01-01

The MEGA experiment is designed to search for the rare decay μ → e γ with a branching ratio sensitivity of /approximately/10 -13 . As is typical of rare-decay experiments, extensive, online filtering of the data is required for MEGA. The MEGA experiment uses a hardware pattern-recognition system based on Programmable Array Logic (PAL) devices. Additional events are eliminated in an online ACP system before data are written to tape. The MEGA trigger system is generally applicable where high-rate, short-propagation-delay trigger systems are required. This report contains an introduction to the MEGA experiment, a discussion of the MEGA hardware trigger system and a discussion of the system's measured performance. 4 refs., 3 figs

Secreted protein eco-corona mediates uptake and impacts of polystyrene nanoparticles on Daphnia magna.

Science.gov (United States)

Nasser, Fatima; Lynch, Iseult

2016-03-30

Nanoparticles (NPs) are defined as having at least one external dimension between 1 and 100 nm. Due to their small size, NPs have a large surface area to volume ratio giving them unique characteristics that differ from bulk material of the same chemical composition. As a result these novel materials have found numerous applications in medical and industrial fields with the result that environmental exposure to NPs is increasingly likely. Similarly, increased reliance on plastic, which degrades extremely slowly in the environment, is resulting in increased accumulation of micro-/nano-plastics in fresh and marine waters, whose ecotoxicological impacts are as yet poorly understood. Although NPs are well known to adsorb macromolecules from their environment, forming a biomolecule corona which changes the NP identity and how it interacts with organisms, significantly less research has been performed on the ecological corona (eco-corona). Secretion of biomolecules is a well established predator-prey response in aquatic food chains, raising the question of whether NPs interact with secreted proteins, and the impact of such interaction on NP uptake and ecotoxicity. We report here initial studies, including optimisation of protocols using carboxylic-acid and amino modified spherical polystyrene NPs, to assess interaction of NPs with biomolecules secreted by Daphnia magna and the impact of these interactions on NP uptake, retention and toxicity towards Daphnia magna. Daphnia magna are an important environmental indicator species who may be especially sensitive to nanoparticles (NPs) as a result of being filter-feeders. This paper demonstrates for the first time that proteins released by Daphnia magna create an eco-corona around polystyrene NPs which causes heightened uptake of the NPs and consequently increases toxicity. The secreted protein eco-corona also causes the NPs to be less efficiently removed from the gut of D. magna and NPs remaining in the gut of D. magna

Paraspidodera uncinata (Nematoda, Lauroiinae as parasite of Cavia magna and Cavia aperea (Rodentia, Caviidae in southern Brazil

Directory of Open Access Journals (Sweden)

Ana Gabriela da Silva Rocha

2015-05-01

Full Text Available Out of the 5 species of Guinea pig registered for Brazil, 4 (Cavia fulgida, C. porcellus, C. aperea, and C. magna have already been reported as hosts of Paraspidodera uncinata. The rodent species C. magna and C. aperea are small-sized mammals, with terrestrial habits, which occur from southern Brazil to eastern Uruguay. Guinea pig specimens donated for research were necropsied for the analysis of endoparasites, and the nematodes found were identified as P. uncinata. The microhabitats of this species were the small and large intestines in C. magna and the large intestine in C. aperea. The prevalence of P. uncinata in the hosts was 60% in C. magna (n = 5 and 14% in C. aperea (n = 7. The record of P. uncinata in different Guinea pig species allows inferring that the foraging mode is similar in the different locations where they occur in southern Brazil, because, perhaps, the infection of hosts has occurred through the ingestion of vegetables contaminated with P. uncinata eggs. This study contributes to knowledge on the helminth fauna of C. magna and C. aperea in southern Brazil.

Ecotoxicological testing of gas oils (daphnia magna test)

Energy Technology Data Exchange (ETDEWEB)

Altmann, B.R.; Mueller, J.; Wenzel, A.; Hensel, R.

2002-02-01

The Water Accomodated Fractions WAF of 4 diesel fuels no. 2 and 4 domestic heating fuels no. 2 of differing origin were analysed on their effect on the mobility of the freshwater crustacean Daphnia Magna. Five loadings per test substance were tested. After an exposition period of 24 h a relationship between loading rates of the WAF and immobility was found for 3 samples, while after 48 h this was observed for all samples. WAF-generation and gas oil data were documented. (orig.) [German] Von 4 Dieselkraftstoff-Gasoelen und 4 Heizoel-Gasoelen EL wurden die Water Accomodated Fractions WAF auf ihre immobilisierende Wirkung auf den Wasserfloh Daphnia Magna untersucht. Von jeder Probe wurden fuenf unterschiedliche Dosierraten geprueft. Nach einer Expositionszeit von 24 Stunden zeigte sich bei 3 Proben und nach 48 Stunden bei allen Proben eine Beziehung zwischen der Dosierrate der Probe und der Immobilitaet. Die Herstellung der WAF und die Daten der Gasoele wurden dokumentiert. (orig.)

Events and mega events: leisure and business in tourism

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Ricardo Alexandre Paiva

2015-12-01

Full Text Available The promotion of events and mega events mobilizes at the same time, in a concatenated way or not, leisure and business practices, which are captured by the tourism industry as a stimulus for the reproduction of capitalism, by the amount of other activities which raise (primary, secondary and tertiary , placing the architecture and the city as protagonists in contemporary urban development. In this sense, the article analyzes the articulation of events and mega events to the provision of architecture and urban infrastructure, as well as the construction of the tourist image of the places, motivated by leisure and business activities. The methodological procedures have theoretical and exploratory character and have multidisciplinary intentions. This will be discussed, in a historical perspective, the concepts of leisure and business activities that raise as moving or traveling; next it will be delimited similarities and differences between tourism events and business tourism, entering after the analysis of the distinctions between events and mega events, highlighting the complexity and the role of mega-events as a major symptom of globalization; finally it will be presented the spatial scale developments in architecture and the city in the realization of (mega events, as well as its impact on the city's image. As a synthesis, it is important to notice that spatial developments business tourism, events and mega events are manifested in various scales and with different levels of complexity, revealing the strengths and / or weaknesses of the places. The urban planning, architecture and urbanism are important objects of knowledge and spatial intervention to ensure infrastructure and urban and architectural structures appropriate for events, which should be sensitive to the demands of tourists and host communities.

Rip Currents, Mega-Cusps, and Eroding Dunes

OpenAIRE

Thornton, E.B.; MacMahan, J.; Sallenger, A.H.

2006-01-01

Submitted to Marine Geology 1 November 2006 Dune erosion is shown to occur at the embayment of beach mega-cusps O(200m alongshore) that are associated with rip currents. The beach is the narrowest at the embayment of the mega-cusps allowing the swash of large storm waves coincident with high tides to reach the toe of the dune, to undercut the dune and to cause dune erosion. Field measurements of dune, beach, and rip current morphology are acquired along an 18 km shoreline in southern Mont...

A Study on the D. magna and V. fischeri Toxicity Relationship of Industrial Wastewater from Korea

Science.gov (United States)

Pyo, S.; Lee, S.; Chun Sang, H.; Park, T. J.; Kim, M. S.

2015-12-01

It is well known that high concentration of TDS (total dissolved solid) in industrial effluent gives rise to the toxicity to the Daphnia magna toxicity test. D. magna is vulnerable to relatively low TDS concentration showing the 24-hr EC50 of Salinity 0.6% (as the sea salt concentration). Recently, standard mandatory toxicity testing using Daphnia magna has been used to monitor industrial effluent toxicity according to Korea standard method (Acute Toxicity Test Method of the Daphnia magna Straus (Cladocera, Crustacea), ES 04704. 1a) under regulation. Since only one acute toxicity testing is applied in the present, we are trying to introduce microbial battery for more complete toxicity assessment. In this study, the acute toxicities between daphnids and microbes were compared. The results of D. magna and Vibrio fischeri toxicity test from 165 industrial wastewater effluents showed high positive correlation. In addition, the possibility of predicting daphnia toxicity from the bacterial toxicity data amounts to 92.6% if we consider salinity effect (>5ppt) together. From this study, we found that the V. fischeri toxicity test is a powerful battery tool to assess the industrial wastewater toxicity. Here, we suggest that luminescent bacteria toxicity test be useful not only for complete toxicity assessment which can't be obtained by daphnia toxicity testing only but also for the reduction cost, time, and labor in the Korean society. Keywords : D. magna, V. fischeri, Industrial waste water, battery test Acknowledgement This research was supported by a grant (15IFIP-B089908-02) from Plant Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government

Sunflower mega-environments in Serbia revealed by GGE biplot analysis

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Balalić Igor

2013-01-01

Full Text Available Sunflower mega-environment analysis was conducted for the grain yield data of 20 hybrids and 19 test locations during 2006, and 20 hybrids and 16 test locations during 2007. Combined data included 15 hybrids and 9 test locations common for both years and it was analyzed as balanced experiment. The analysis of variance components showed that hybrid by location interaction explained 2.74, 5.8, and 3.72 times more variation than hybrid, for grain yield, for 2006, 2007, combined data, respectively, and indicated potential mega-environment existence. Our results showed the existence of two mega-environments in Serbia sunflower growing region: (1 Kula Vitovnica, Aleksa Šantić, Sombor and (2 Rimski Šančevi, Kikinda. It has been concluded that if we want promising sunflower hybrids to be optimally used, they should be cropped differently for the two determined mega-environments.

Toxicity and genotoxicity of the quaternary ammonium compound benzalkonium chloride (BAC) using Daphnia magna and Ceriodaphnia dubia as model systems

International Nuclear Information System (INIS)

Lavorgna, Margherita; Russo, Chiara; D'Abrosca, Brigida; Parrella, Alfredo; Isidori, Marina

2016-01-01

The toxicity and genotoxicity of the cationic surfactant benzalkonium chloride (BAC) were studied using Daphnia magna and Ceriodaphnia dubia as model systems. Acute and chronic toxicity testing were performed according to the international standard guidelines and the genotoxicity was detected through the comet assay on cells from whole organisms in vivo exposed. Acute effects occurred at concentrations in the order of tens of μg/L in D. magna and hundreds of μg/L in C. dubia. Chronic effects were found at one order of magnitude less than short-term effects maintaining the same difference in sensitivity between D. magna and C. dubia. BAC induced relevant DNA damage, in both cladocerans; the lowest adverse effect levels were 0.4 and 4 ng/L for D. magna and C. dubia, respectively. As these effective concentrations are far lower than BAC occurrence in surface waters (units of μg/L) a concerning environmental risk cannot be excluded. The findings of this study showed that D. magna and C. dubia, could be used as model organisms to detect acute and chronic toxicity as well as genotoxicity at the whole organism level. - Highlights: • Benzalkonium chloride chronic effect in C. dubia was found at dozens of μg/L. • The LOAEC detected by comet assay in D. magna is in the order of hundreds of pg/L. • D. magna and C. dubia are useful model organisms to detect toxicity and genotoxicity. - Benzalkonium chloride showed chronic toxicity and genotoxicity in Daphnia magna and Ceriodaphnia dubia at concentrations of environmental concern. Daphnids are useful model organisms.

MEGA-CC: computing core of molecular evolutionary genetics analysis program for automated and iterative data analysis.

Science.gov (United States)

Kumar, Sudhir; Stecher, Glen; Peterson, Daniel; Tamura, Koichiro

2012-10-15

There is a growing need in the research community to apply the molecular evolutionary genetics analysis (MEGA) software tool for batch processing a large number of datasets and to integrate it into analysis workflows. Therefore, we now make available the computing core of the MEGA software as a stand-alone executable (MEGA-CC), along with an analysis prototyper (MEGA-Proto). MEGA-CC provides users with access to all the computational analyses available through MEGA's graphical user interface version. This includes methods for multiple sequence alignment, substitution model selection, evolutionary distance estimation, phylogeny inference, substitution rate and pattern estimation, tests of natural selection and ancestral sequence inference. Additionally, we have upgraded the source code for phylogenetic analysis using the maximum likelihood methods for parallel execution on multiple processors and cores. Here, we describe MEGA-CC and outline the steps for using MEGA-CC in tandem with MEGA-Proto for iterative and automated data analysis. http://www.megasoftware.net/.

In vivo biodegradation of colloidal quantum dots by a freshwater invertebrate, Daphnia magna

Energy Technology Data Exchange (ETDEWEB)

Kwon, Dongwook; Kim, Min Jung; Park, Chansik; Park, Jaehong [Department of Chemistry, Hanyang University, Seoul 133-791 (Korea, Republic of); Choi, Kyungho [Department of Environmental Health, Seoul National University, Seoul 151-742 (Korea, Republic of); Yoon, Tae Hyun, E-mail: thyoon@gmail.com [Department of Chemistry, Hanyang University, Seoul 133-791 (Korea, Republic of)

2012-06-15

Impacts of planktonic invertebrate, Daphnia magna, on the speciation of colloidal quantum dots (QD) were investigated using fluorescence spectromicroscopic technique. Well-dispersed {sup GA/TOPO}QD were prepared by forming a supramolecular assembly of hydrophobic {sup TOPO}QD with biomacromolecules (i.e., Gum Arabic, GA). Biological degradation of this nanomaterial was monitored by fluorescence spectromicroscopic methods. Our study confirmed the major uptake pathway of manufactured nanomaterials and in vivo biodegradation processes in a well-known toxicity test organism, D. magna. In addition, we also found that D. magna can induce significant deterioration of aquatic media by releasing fragments of partially degraded QD colloids. These biological processes may significantly change the predicted toxicities of nanomaterials in aquatic environments. Thus, we propose that the impacts of aquatic living organisms on the environmental fate of manufactured nanomaterials (MNs) should be carefully taken into account when assessing the risk of MNs to the environment and human health.

Multi-generational effects of propranolol on Daphnia magna at different environmental concentrations

International Nuclear Information System (INIS)

Jeong, Tae-Yong; Kim, Hyun Young; Kim, Sang Don

2015-01-01

To evaluate the effects of propranolol on Daphnia magna (D. magna), we employed a multi-generational exposure period for eight generations and an environmentally relevant low concentration with 1.5 ng/L, 0.2 μg/L and 26 μg/L to reflect a realistic exposure scenario. Physiological endpoints were checked, including growth, number of neonates, heart rate, frequency of abdominal appendage movement and malformation rate of neonates. In the results, growth and abdominal appendage movement were affected by environmental concentration during several generations, and the responses showed consistent tendencies of response increase with concentration increase. Heart rate was the only endpoint affected throughout all exposure generations. Inhibitory and acceleratory effects on heart rate, growth and abdominal appendage movement suggest that it is necessary to cover sub-lethal endpoints of non-targeted organisms in eco-toxicity study because the physiological responses were detected at much lower concentrations than the results of traditional toxicity tests, including environmental concentration. - Highlights: • Multi-generational exposure was conducted to evaluate the effect of propranolol on Daphnia magna. • Heart rate was the only endpoint affected throughout all exposure generations. • Growth and abdominal appendage movement were affected at environmental concentrations. • Time series fluctuations in responses appeared with no tendencies throughout all generations. • It is necessary to cover sub-organismal endpoints and long-term exposure in ecotoxicity test. - Heart rate, growth and abdominal appendage movement of D. magna were affected by the multigenerational exposure of propranolol at environmental levels.

Development of MicroMegas for a Digital Hadronic Calorimeter

OpenAIRE

Adloff, Catherine; Blaha, Jan; Espargiliere, Ambroise; Karyotakis, Yannis

2009-01-01

Recent developments on the MicroMegas prototypes built by use of the bulk technology with analog and digital readout electronics are presented. The main test beam results of a stack of several MicroMegas prototypes fully comply with the needs of a hadronic calorimeter for future particle physics experiments. A technical solution for a large scale prototype is also introduced.

Development and calibration of the tracking Compton/Pair telescope MEGA

International Nuclear Information System (INIS)

Kanbach, G.; Andritschke, R.; Zoglauer, A.; Ajello, M.; McConnell, M.L.; Macri, J.R.; Ryan, J.M.; Bloser, P.; Hunter, S.; DiCocco, G.; Kurfess, J.; Reglero, V.

2005-01-01

We describe the development and tests of the prototype for a new telescope for Medium Energy Gamma-ray Astronomy (MEGA) in the energy band 0.4-50 MeV. As a successor to COMPTEL and EGRET (at low energies), MEGA aims to improve the sensitivity for astronomical sources by at least an order of magnitude. It could thus fill the severe sensitivity gap between scheduled or operating hard-X-ray and high-energy gamma-ray missions and open the way for a future Advanced Compton Telescope. MEGA records and images γ-rays by completely tracking Compton and Pair creation events in a stack of double-sided Si-strip track detectors surrounded by a pixelated CsI calorimeter. A scaled down prototype has been built and we describe technical details of its design and properties. Results from calibrations using radioactive sources and from measurements with an accelerator generated, fully polarized, γ-ray beam are presented and an outlook to future plans with MEGA is given

The protective effects of vitamin E on microcephaly in rats X-irradiated in utero: DNA, lipid peroxide and confronting cisternae

International Nuclear Information System (INIS)

Tanaka, Harumi; Iwasaki, Setsuo; Inomata, Kenichirou; Nasu, Fumio; Nishimura, Shigeru

1986-01-01

Fetuses from rats given either water or 0.03% D,L-α-tocopherol acetate (vitamin E) as a drinking fluid and X-irradiated with 100 rad on gestational day 13 were examined on gestational day 21. Mean cerebral weight which was significantly reduced by the X-irradiation was increased by vitamin E supplementation but the level did not reach that in sham-irradiated controls. Administration of vitamin E caused an increase in DNA concentration which was significantly reduced by X-irradiation with water treatment. An increase in the mean level of lipid peroxide formation was observed in the water-treated, X-irradiated group in the sample at zero time but not in the vitamin E-treated, X-irradiated group. In the cytoplasm of fetal cerebral neurons from X-irradiated dams with vitamin E supplementation, confronting cisternae were frequently observed between two nuclear envelopes. Confronting cisternae may be considered as a repair mechanism of vitamin E against X-irradiated neuronal damage in the fetal cerebrum. This study provides evidence of the protection by vitamin E of neuronal development in X-irradiated fetuses, through its antioxidant properties, against attacks by free radicals and/or lipid peroxide. (orig.)

Genetic variation in the cellular response of Daphnia magna (Crustacea: Cladocera) to its bacterial parasite.

Science.gov (United States)

Auld, Stuart K J R; Scholefield, Jennifer A; Little, Tom J

2010-11-07

Linking measures of immune function with infection, and ultimately, host and parasite fitness is a major goal in the field of ecological immunology. In this study, we tested for the presence and timing of a cellular immune response in the crustacean Daphnia magna following exposure to its sterilizing endoparasite Pasteuria ramosa. We found that D. magna possesses two cell types circulating in the haemolymph: a spherical one, which we call a granulocyte and an irregular-shaped amoeboid cell first described by Metchnikoff over 125 years ago. Daphnia magna mounts a strong cellular response (of the amoeboid cells) just a few hours after parasite exposure. We further tested for, and found, considerable genetic variation for the magnitude of this cellular response. These data fostered a heuristic model of resistance in this naturally coevolving host-parasite interaction. Specifically, the strongest cellular responses were found in the most susceptible hosts, indicating resistance is not always borne from a response that destroys invading parasites, but rather stems from mechanisms that prevent their initial entry. Thus, D. magna may have a two-stage defence--a genetically determined barrier to parasite establishment and a cellular response once establishment has begun.

Rip currents, mega-cusps, and eroding dunes

Science.gov (United States)

Thornton, E.B.; MacMahan, J.; Sallenger, A.H.

2007-01-01

Dune erosion is shown to occur at the embayment of beach mega-cusps O(200 m alongshore) that are associated with rip currents. The beach is the narrowest at the embayment of the mega-cusps allowing the swash of large storm waves coincident with high tides to reach the toe of the dune, to undercut the dune and to cause dune erosion. Field measurements of dune, beach, and rip current morphology are acquired along an 18 km shoreline in southern Monterey Bay, California. This section of the bay consists of a sandy shoreline backed by extensive dunes, rising to heights exceeding 40 m. There is a large increase in wave height going from small wave heights in the shadow of a headland, to the center of the bay where convergence of waves owing to refraction over the Monterey Bay submarine canyon results in larger wave heights. The large alongshore gradient in wave height results in a concomitant alongshore gradient in morphodynamic scale. The strongly refracted waves and narrow bay aperture result in near normal wave incidence, resulting in well-developed, persistent rip currents along the entire shoreline. The alongshore variations of the cuspate shoreline are found significantly correlated with the alongshore variations in rip spacing at 95% confidence. The alongshore variations of the volume of dune erosion are found significantly correlated with alongshore variations of the cuspate shoreline at 95% confidence. Therefore, it is concluded the mega-cusps are associated with rip currents and that the location of dune erosion is associated with the embayment of the mega-cusp.

Protective effects of vitamin E on microcephaly in rats X-irradiated in utero: DNA, lipid peroxide and confronting cisternae

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Harumi; Iwasaki, Setsuo; Inomata, Kenichirou; Nasu, Fumio; Nishimura, Shigeru

1986-06-01

Fetuses from rats given either water or 0.03% D,L-..cap alpha..-tocopherol acetate (vitamin E) as a drinking fluid and X-irradiated with 100 rad on gestational day 13 were examined on gestational day 21. Mean cerebral weight which was significantly reduced by the X-irradiation was increased by vitamin E supplementation but the level did not reach that in sham-irradiated controls. Administration of vitamin E caused an increase in DNA concentration which was significantly reduced by X-irradiation with water treatment. An increase in the mean level of lipid peroxide formation was observed in the water-treated, X-irradiated group in the sample at zero time but not in the vitamin E-treated, X-irradiated group. In the cytoplasm of fetal cerebral neurons from X-irradiated dams with vitamin E supplementation, confronting cisternae were frequently observed between two nuclear envelopes. Confronting cisternae may be considered as a repair mechanism of vitamin E against X-irradiated neuronal damage in the fetal cerebrum. This study provides evidence of the protection by vitamin E of neuronal development in X-irradiated fetuses, through its antioxidant properties, against attacks by free radicals and/or lipid peroxide. 35 refs.; 3 figs.; 1 table.

Mega-Planning in Population

Science.gov (United States)

Clark, Sarah C.; Murray, Margo

2005-01-01

Clark and Murray examine the six Critical Performance Factors for Mega planning in an example drawn from the five-year history of the population program of a major west coast philanthropy. In this article, the authors describe the salience and scope of the population issue as it is relates to other global trends; the steps the foundation took to…

Análise do líquido cefalorraquidiano de bugio-ruivo (Alouatta guariba

Directory of Open Access Journals (Sweden)

Marcos V. Tranquilim

2013-12-01

Full Text Available A presente pesquisa foi realizada com o objetivo de desenvolver e adaptar técnicas diagnósticas em neurologia para primatas não humanos, da espécie Alouatta guariba Geoffroy Saint-Hilaire, 1812 (bugio-ruivo saudáveis e mantidos em cativeiro. Foram realizadas análises físico-químicas e citológicas do líquido cefalorraquidiano obtido na cisterna magna de oito bugios-ruivos. Para realização dos exames, todos os animais foram contidos quimicamente com associação de cetamina, xilazina e midazolam e anestesia inalatória com isoflurano. Os resultados das análises do líquido cefalorraquidiano demonstraram valores médios de proteína: 16,92mg/dL±9,84; glicose: 131,25mg/dL±106,7; pH: 8,37±0,69; células nucleadas: 0,5/mm³±0,75; hemácias: 49,37/mm³±111,76 e pressão: 7,37cm H2O±1,77. O trabalho demonstrou a segurança e a eficácia da colheita do líquido cefalorraquidiano na cisterna magna de Alouatta guariba e os valores de referência para a espécie.

Magna Carta: Teaching Medieval Topics for Historical Significance

Science.gov (United States)

Metzger, Scott Alan

2010-01-01

The Middle Ages are an immensely important era in the Western experience. Unfortunately, medieval studies are often marginalized or trivialized in school curriculum. With the approach of the 800th anniversary of Magna Carta, the famous charter of rights from medieval England, one has a timely and useful example for considering what a focus on…

MEGA - A next generation mission in Medium Energy Gamma-Ray Astronomy

International Nuclear Information System (INIS)

Kanbach, Gottfried

2001-01-01

A Medium Energy Gamma-Ray Astronomy (MEGA) detector is being developed and proposed for a small satellite mission. MEGA intends to improve the sensitivity at medium γ-ray energies (0.4-50 MeV) by at least an order of magnitude with respect to past instruments. Its large field of view will be especially important for the discovery of transient sources and for conducting all-sky surveys. Key science objectives for MEGA are the investigation of cosmic high-energy accelerators and of nucleosynthesis sites with γ-ray lines. The large-scale structure of the galactic and cosmic diffuse background is another important goal for this mission. MEGA records and images γ-ray events by completely tracking Compton and pair creation interactions in a stack of double sided Si-strip track detectors and 3-D resolving CsI calorimeters

SCALES OF FLOWS: Qatar and the Urban Legacies of Mega Events

Directory of Open Access Journals (Sweden)

Anna Grichting

2013-07-01

Full Text Available In 2022, Qatar will become the first Middle Eastern and Arab country to host such an  important Mega-Event as the FIFA World Cup. Global cultural and sporting Mega Events  ave driven the urban transformation of cities such as Barcelona, London, Rio, Beijing,Shanghai, and Lisbon and the spectacle and economic boosterism encourages cities to  compete on the World Stage for these events. The best practices of successful bids and  their enduring legacies create a knowledge and policy flow of Mega Event strategies for global branding and sustainable Urban, Social, and Economic Development at the local and regional scales. This paper discusses the urban legacies that will result from Qatar hosting the World Cup and other Mega Events, and questions how an emerging global host city like Doha will benefit on the long and short term.

Upper motor neurone modulation of the structure of the terminal cisternae in rat skeletal muscle fibres.

Science.gov (United States)

Dulhunty, A F; Gage, P W; Valois, A A

1981-12-23

There are fewer indentations on the flat surfaces of terminal cisternae in soleus (slow-twitch) than in extensor digitorum longus (EDL, fast-twitch) muscle fibres of rats. Following mid-thoracic spinal cord transection, there is an increase in the number of indentations in soleus fibres but no change in EDL fibres. The increase in the numbers of indentations after spinal cord transections is correlated with changes in the contractile and charge movement properties of the soleus fibres so that they resemble normal EDL fibres. The indentations appear to have an important role in excitation-contraction coupling.

Ecotoxicological effect of ketamine: Evidence of acute, chronic and photolysis toxicity to Daphnia magna.

Science.gov (United States)

Li, Shih-Wei; Wang, Yu-Hsiang; Lin, Angela Yu-Chen

2017-09-01

Ketamine has been increasingly used in medicine and has the potential for abuse or illicit use around the world. Ketamine cannot be removed by conventional wastewater treatment plants. Although ketamine and its metabolite norketamine have been detected to a significant degree in effluents and aquatic environments, their ecotoxicity effects in aquatic organisms remain undefined. In this study, we investigated the acute toxicity of ketamine and its metabolite, along with the chronic reproductive toxicity of ketamine (5-100μg/L) to Daphnia magna. Multiple environmental scenarios were also evaluated, including drug mixtures and sunlight irradiation toxicity. Ketamine and norketamine caused acute toxicity to D. magna, with half lethal concentration (LC 50 ) values of 30.93 and 25.35mg/L, respectively, after 48h of exposure. Irradiated solutions of ketamine (20mg/L) significantly increased the mortality of D. magna; pre-irradiation durations up to 2h rapidly increased the death rate to 100%. A new photolysis byproduct (M.W. 241) of norketamine that accumulates during irradiation was identified for the first time. The relevant environmental concentration of ketamine produced significant reproductive toxicity effects in D. magna, as revealed by the reduction of the number of total live offspring by 33.6-49.8% (p ketamine concentration cannot be ignored and warrant further examination. Copyright © 2017 Elsevier Inc. All rights reserved.

The response of European Daphnia magna Straus and Australian Daphnia carinata King to changes in geomagnetic field.

Science.gov (United States)

Krylov, Viacheslav V; Bolotovskaya, Irina V; Osipova, Elena A

2013-03-01

This study investigates the effects of lifelong exposure to reversed geomagnetic and zero geomagnetic fields (the latter means absence of geomagnetic field) on the life history of Daphnia carinata King from Australia and Daphnia magna Straus from Europe. Considerable deviation in the geomagnetic field from the usual strength, leads to a decrease in daphnia size and life span. Reduced brood sizes and increased body length of neonates are observed in D. magna exposed to unusual magnetic background. The most apparent effects are induced by zero geomagnetic field in both species of Daphnia. A delay in the first reproduction in zero geomagnetic field is observed only in D. magna. No adaptive maternal effects to reversed geomagnetic field are found in a line of D. magna maintained in these magnetic conditions for eight generations. Integrally, the responses of D. magna to unusual geomagnetic conditions are more extensive than that in D. carinata. We suggest that the mechanism of the effects of geomagnetic field reversal on Daphnia may be related to differences in the pattern of distribution of the particles that have a magnetic moment, or to moving charged organic molecules owing to a change in combined outcome and orientation of the geomagnetic field and Earth's gravitational field. The possibility of modulation of self-oscillating processes with changes in geomagnetic field is also discussed.

Uptake and depuration of gold nanoparticles in Daphnia magna

DEFF Research Database (Denmark)

Skjolding, Lars Michael; Kern, Kristina; Hjorth, Rune

2014-01-01

This study presents a series of short-term studies (total duration 48 h) of uptake and depuration of engineered nanoparticles (ENP) in neonate Daphnia magna. Gold nanoparticles (Au NP) were used to study the influence of size, stabilizing agent and feeding on uptake and depuration kinetics...

Leverage of a sport mega-event branding : a case study of the 2010 FIFA World Cup

OpenAIRE

2014-01-01

D.Comm. (Sport Management) The primary objective of the study was to establish what brand leverage strategies could be implemented in sport mega-event branding based on the case study of the 2010 FIFA World Cup South Africa. The secondary objectives focused on discovering the dimensions of sport mega-event branding, investigating the areas of sport mega-event impacts and leverage, identifying sport mega-event brand leverage activation tools and understanding the role of mega-event brand le...

Free ionic nickel accumulation and localization in the freshwater zooplankter, Daphnia magna

International Nuclear Information System (INIS)

Hall, T.M.

1982-01-01

The processes which lead to the accumulation of free ionic nickel (radioactive) from solution by Daphnia magna were studied and incorporated into a model which describes accummulation at different concentrations. Adsorption proved to be a relatively small component of nickel accummulation. The accummulation rate eventually approached zero, which represented an equilibrium between uptake and loss of nickel. However, elimination experiments did reveal a pool of relatively static nickel. The appearance and distribution of nickel within five body parts (body fluid, carapace, gut, filtering appendages, and eggs) of D. magna supported the accummulation data and added to the understanding of the pathways of nickel through the organism

Bioassay of Phenol and its Intermediate Products Using Daphnia magna

Directory of Open Access Journals (Sweden)

Afshin Maleki

2008-06-01

Full Text Available Phenol is one of the most common compounds found in many industrial effluents such as petroleum refining and petrochemicals, pharmaceuticals, pesticides, paint and dye industries, organic chemicals manufacturing, etc. The contamination of bodies of water with phenol is a serious problem in terms of environmental considerations due to its high toxicity. In this study, toxicity of phenol and its degradation mixtures by sonochemical, photochemical, and photosonochemical processes were investigated. Toxicity assay tests were carried out using Daphnia magna as a bio-indicator. The sonochemical and photochemical experiments were carried out using a bath sonicator (500 W working at 35 and 130 kHz frequencies and with a 400 W medium pressure mercury lamp, respectively. Experiments were performed at initial concentrations of 100 mg L-1. Bioassay tests showed that phenol was toxic to D.magna and so resulted in quite low LC50 values. Comparison of toxicity units (TU between phenol and effluent toxicity showed that TU value for photosonochemical effluent was lower than that obtained for phenol, photochemical effluent, and sonochemical effluent. It was found that the toxicity unit of photochemical effluent was lower than that obtained for sonochemical effluent. According to the D.magna acute toxicity test, it is concluded that photosonolysis and photolysis are capable of decreasing the toxicity of by-products formed during the degradation of phenol aqueous solutions. Photosonic and photolytic processes can, therefore, be recommended as a potential approach to the treatment of phenolic wastewater.

The acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ionic liquids on Chlorella vulgaris and Daphnia magna.

Science.gov (United States)

Zhang, Cheng; Zhang, Shuai; Zhu, Lusheng; Wang, Jinhua; Wang, Jun; Zhou, Tongtong

2017-10-01

Given their increasingly widespread application, the toxic effects of ionic liquids (ILs) have become the subject of significant attention in recent years. Therefore, the present study assessed the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate ([C n mim]NO 3 (n = 2, 4, 6, 8, 10, 12)) on Chlorella vulgaris and Daphnia magna. The sensitivity of the tested organism Daphnia magna and the investigated IL concentrations in water using high-performance liquid chromatography (HPLC) were also evaluated to demonstrate the reliability of the present study. The results illustrated that Daphnia magna is indeed sensitive to the reference toxicant and the investigated ILs were stable in the aquatic environment. The 50% effect concentration (EC 50 ) was used to represent the acute toxic effects on Chlorella vulgaris and Daphnia magna. With the increasing alkyl-chain lengths, the toxicity of the investigated ILs increased in both the test organisms. Accordingly, the alkyl-chain lengths can cause significantly toxic effects on aquatic organisms, and Daphnia magna are much more sensitive than Chlorella vulgaris to the imidazolium-based ILs used in the present study. Furthermore, the present study provides more information on the acute toxic effects of 1-alkyl-3-methylimidazolium nitrate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Global mega forces: Implications for the future of natural resources

Science.gov (United States)

George H. Kubik

2012-01-01

The purpose of this paper is to provide an overview of leading global mega forces and their importance to the future of natural resource decisionmaking, policy development, and operation. Global mega forces are defined as a combination of major trends, preferences, and probabilities that come together to produce the potential for future high-impact outcomes. These...

Magna Carta Libertatum – osmisté výročí

Czech Academy of Sciences Publication Activity Database

Blahož, Josef

2015-01-01

Roč. 154, č. 6 (2015), s. 449-464 ISSN 0231-6625 Institutional support: RVO:68378122 Keywords : Magna Carta Libertatum * development of constitutionalism * rule of law Subject RIV: AG - Legal Sciences

Accessing the mega-region : evaluating the role of livable community patterns in Gulf Coast mega-region planning.

Science.gov (United States)

2015-03-01

This research analyzes both the need and mechanisms for integrating livability components such as : transit and active transportation into a broader mega-regions transportation framework. The research : builds a conceptual framework for understanding...

Single nucleotide polymorphism discovery from expressed sequence tags in the waterflea Daphnia magna

Directory of Open Access Journals (Sweden)

Souche Erika L

2011-06-01

Full Text Available Abstract Background Daphnia (Crustacea: Cladocera plays a central role in standing aquatic ecosystems, has a well known ecology and is widely used in population studies and environmental risk assessments. Daphnia magna is, especially in Europe, intensively used to study stress responses of natural populations to pollutants, climate change, and antagonistic interactions with predators and parasites, which have all been demonstrated to induce micro-evolutionary and adaptive responses. Although its ecology and evolutionary biology is intensively studied, little is known on the functional genomics underpinning of phenotypic responses to environmental stressors. The aim of the present study was to find genes expressed in presence of environmental stressors, and target such genes for single nucleotide polymorphic (SNP marker development. Results We developed three expressed sequence tag (EST libraries using clonal lineages of D. magna exposed to ecological stressors, namely fish predation, parasite infection and pesticide exposure. We used these newly developed ESTs and other Daphnia ESTs retrieved from NCBI GeneBank to mine for SNP markers targeting synonymous as well as non synonymous genetic variation. We validate the developed SNPs in six natural populations of D. magna distributed at regional scale. Conclusions A large proportion (47% of the produced ESTs are Daphnia lineage specific genes, which are potentially involved in responses to environmental stress rather than to general cellular functions and metabolic activities, or reflect the arthropod's aquatic lifestyle. The characterization of genes expressed under stress and the validation of their SNPs for population genetic study is important for identifying ecologically responsive genes in D. magna.

Tratamento cirúrgico do megaesôfago recidivado

Directory of Open Access Journals (Sweden)

José Luiz Braga de Aquino

Full Text Available OBJETIVO: Avaliar os resultados do tratamento cirúrgico em uma série de pacientes submetidos ao tratamento prévio para megaesôfago que evoluíram com recidiva de sintomas. MÉTODO: Analisou-se os resultados das diversas técnicas operatórias realizadas em 47 pacientes pelo Serviços de Cirurgia Geral e Torácica do HMCP-PUC-Campinas. A morbidade pós-cirúrgica, mortalidade, o alívio ou nova recidiva de sintomas e o tempo de seguimento foram os principais indicadores. Dividiu-se a série em três grupos, de acordo com o grau da afecção: Incipiente (nove casos, Não-avançado (18 casos e avançado (20 casos. As técnicas operatórias utilizadas foram: à cardiomiectomia com fundoplicatura anterior, esofagocardioplastia à Tahl, esofagocardioplastia à Serra-Dória, Esofagectomia Subtotal e Mucosectomia com conservação da túnica muscular esofágica. RESULTADOS: Obteve-se índices de resolutividade satisfatórios com a técnica de cardiomiectomia com fundoplicatura para o megaesôfago Incipiente, com baixa morbidade. Nos megaesôfago não-avançado, as cardiopatias, em especial a esofagocardioplastia à Serra-Dória mostram se mais adequadas. A terapêutica do megaesôfago avançado apresentou as maiores taxas de morbidade e demonstrou superioridade das técnicas mais agressivas em relação às técnicas conservadoras, em especial a mucosectomia com preservação da túnica muscular, sendo esta a técnica com menor morbidade dentro do grupo avançado. CONCLUSÃO: A difícil padronização do tratamento cirúrgico do megaesôfago recidivado deve-se às inúmeras técnicas disponíveis, às habilidades pessoais dos cirurgiões e atenta para a criação de protocolos terapêuticos.

Acute and chronic toxicity of veterinary antibiotics to Daphnia magna

DEFF Research Database (Denmark)

Wollenberger, Leah; Halling-Sørensen, B.; Kusk, Kresten Ole

2000-01-01

The acute and chronic toxicity of nine antibiotics used both therapeutically and as growth promoters in intensive farming was investigated on the freshwater crustacean Daphnia magna. The effect of the antibiotics metronidazole (M), olaquindox (OL), oxolinic acid (OA), oxytetracycline (OTC...

Open-Access Mega-Journals: A Bibliometric Profile.

Science.gov (United States)

Wakeling, Simon; Willett, Peter; Creaser, Claire; Fry, Jenny; Pinfield, Stephen; Spezi, Valérie

2016-01-01

In this paper we present the first comprehensive bibliometric analysis of eleven open-access mega-journals (OAMJs). OAMJs are a relatively recent phenomenon, and have been characterised as having four key characteristics: large size; broad disciplinary scope; a Gold-OA business model; and a peer-review policy that seeks to determine only the scientific soundness of the research rather than evaluate the novelty or significance of the work. Our investigation focuses on four key modes of analysis: journal outputs (the number of articles published and changes in output over time); OAMJ author characteristics (nationalities and institutional affiliations); subject areas (the disciplinary scope of OAMJs, and variations in sub-disciplinary output); and citation profiles (the citation distributions of each OAMJ, and the impact of citing journals). We found that while the total output of the eleven mega-journals grew by 14.9% between 2014 and 2015, this growth is largely attributable to the increased output of Scientific Reports and Medicine. We also found substantial variation in the geographical distribution of authors. Several journals have a relatively high proportion of Chinese authors, and we suggest this may be linked to these journals' high Journal Impact Factors (JIFs). The mega-journals were also found to vary in subject scope, with several journals publishing disproportionately high numbers of articles in certain sub-disciplines. Our citation analsysis offers support for Björk & Catani's suggestion that OAMJs's citation distributions can be similar to those of traditional journals, while noting considerable variation in citation rates across the eleven titles. We conclude that while the OAMJ term is useful as a means of grouping journals which share a set of key characteristics, there is no such thing as a "typical" mega-journal, and we suggest several areas for additional research that might help us better understand the current and future role of OAMJs in

The primary opinion on the formation mechanisms of mega dunes and lakes in the Badain jaran desert

International Nuclear Information System (INIS)

Guo Yonghai; Li Yawei

2010-01-01

Badain Jaran Desert is famous in distribution of many lakes and mega dunes in the world. Up to now, there are several different opinions about formation problems of lakes and mega dunes. Actually, these problems are directly correlated to the groundwater circulation and alternation in the area. Refering to the prevenient research results and combining with the current hydrogeological investigation in the desert, the paper discussed the problems about the formation mechanisms of lakes and mega dunes. The Primary cognition is that: the lakes in the desert were formed mainly by the lateral recharge of groundwaters both from Yabulai mountain and mega dunes. The formation of the mega dunes was related nearly to the rainfall and groundwater in the area. The formation and coexistence relationship between lakes and mega dunes is that: the mega dunes were formed firstly, and then the lakes. That is to say the mega dunes are the basic conditions for the lake formation. (authors)

Protein profiling as early detection biomarkers for TiO2 nanoparticle toxicity in Daphnia magna.

Science.gov (United States)

Sá-Pereira, Paula; Diniz, Mário S; Moita, Liliana; Pinheiro, Teresa; Mendonça, Elsa; Paixão, Susana M; Picado, Ana

2018-05-01

The mode of action for nanoparticle (NP) toxicity in aquatic organisms is not yet fully understood. In this work, a strategy other than toxicity testing was applied to Daphnia magna exposed to TiO 2 -NPs: the use of nuclear microscopy and the assessment of protein profile. D. magna is a keystone species broadly used as a model system in ecotoxicology. Titanium (Ti) was found in the D. magna digestive tract, mainly in the gut. The penetration of Ti into the epithelial region was greater at higher exposure levels and also observed in eggs in the brood pouch. The protein profile of individuals exposed to different concentrations showed that 2.8 and 5.6 mg/L TiO 2 -NP concentrations induced an over-expression of the majority of proteins, in particular proteins with molecular weight of ∼120, 85 and 15 kDa, while 11.2 mg/L TiO 2 -NP had an inhibitory effect on protein expression. The Matrix-assisted laser desorption ionization with tandem time of flight mass spectrometry (MALDI-TOF/TOF MS) analysis of these proteins consistently identified them as vitellogenin (Vtg)-like proteins, associated with enzymes involved in redox balance. These results indicate that Vtg-like proteins are up-regulated in D. magna exposed to TiO 2 -NPs. Vitellogenesis is associated with the reproduction system, suggesting that TiO 2 -NP exposure can impair reproduction by affecting this process. The precise mode of action of TiO 2 -NPs is still unclear and the results from this study are a first attempt to identify specific proteins as potential markers of TiO 2 -NP toxicity in D. magna, providing useful information for future research.

Different impacts of mega-ENSO and conventional ENSO on the Indian summer rainfall: developing phase

Science.gov (United States)

Zhang, Lei; Wu, Zhiwei; Zhou, Yefan

2016-04-01

Mega-El Niño-Southern Oscillation (ENSO), a boarder version of conventional ENSO, is found to be a main driving force of Northern Hemisphere summer monsoon rainfall including the Indian summer rainfall (ISR). The simultaneous impacts of "pure" mega-ENSO and "pure" conventional ENSO events on the ISR in its developing summer remains unclear. This study examines the different linkages between mega-ENSO-ISR and conventional ENSO-ISR. During the developing summer of mega-El Niño, negative rainfall anomalies are seen over the northeastern Indian subcontinent, while the anomalous rainfall pattern is almost the opposite for mega-La Niña; as for the conventional ENSO, the approximate "linear opposite" phenomenon vanishes. Furthermore, the global zonal wave trains anomalous are found at mid-latitude zones, with a local triple circulation pattern over the central-east Eurasia during mega-ENSO events, which might be an explanation of corresponding rainfall response over the Indian Peninsula. Among 106-year historical run (1900-2005) of 9 state-of-the-art models from the Coupled Model Inter-comparison Project Phase 5 (CMIP5), HadGEM2-ES performs a promising skill in simulating the anomalous circulation pattern over mid-latitude and central-east Eurasia while CanESM2 cannot. Probably, it is the models' ability of capturing the mega-ENSO-ISR linkage and the characteristic of mega-ENSO that make the difference.

Mega-Analysis of School Psychology Blueprint for Training and Practice Domains

Science.gov (United States)

Burns, Matthew K.; Kanive, Rebecca; Zaslofsky, Anne F.; Parker, David C.

2013-01-01

Meta-analytic research is an effective method for synthesizing existing research and for informing practice and policy. Hattie (2009) suggested that meta-analytic procedures could be employed to existing meta-analyses to create a mega-analysis. The current mega-analysis examined a sample of 47 meta-analyses according to the "School…

Strategies simulation model for the gas business chain MEGAS

International Nuclear Information System (INIS)

Gonzalez, S.M. de; Uzcategui, R.; Brea, E.; Diaz, R.

1994-01-01

MEGAS is a simulation model representing fundamental parameters of Corpoven's natural gas and NGL production, handling, processing, transportation and distribution systems in the Venezuelan mid-east, as well as its financial implications. Various strategies regarding development, prices, costs, new business opportunities, production scenarios, demand and energy policies can be evaluated through this model in order to determine, after analyzing the economics results, a set of strategies to follow in the mid and long term. MEGAS could be also used to make risk analysis studies, considering that probabilistic parameters and variables like gas quality, production, demand, plant shutdowns and others are to be represented by their distinctive function. It is possible to set up a probabilistic function for each economic indicator or operating variables with an appropriate experiment design. MEGAS is based on a dynamic simulation language, which facilitates both the real system components representation and the main variables statistical data accumulation. It also allows graphical representation of results and the simulation animation. Demand and price forecasts, new projects, costs and capabilities of the systems are some of the model input data. MEGAS should be considered as a tool that eases the strategic planning of the business, making it possible for the Corporation to foresee changes, both in the domestic and international market, to predict how these changes could affect its business affairs and to visualize different return scenarios

Rapid changes in water hardness and alkalinity: Calcite formation is lethal to Daphnia magna.

Science.gov (United States)

Bogart, Sarah J; Woodman, Samuel; Steinkey, Dylan; Meays, Cindy; Pyle, Greg G

2016-07-15

There is growing concern that freshwater ecosystems may be negatively affected by ever-increasing anthropogenic inputs of extremely hard, highly alkaline effluent containing large quantities of Ca(2+), Mg(2+), CO3(2-), and HCO3(-) ions. In this study, the toxicity of rapid and extreme shifts in water hardness (38-600mg/L as CaCO3) and alkalinity (30-420mg/L as CaCO3) to Daphnia magna was tested, both independently and in combination. Within these ranges, where no precipitation event occurred, shifts in water hardness and/or alkalinity were not toxic to D. magna. In contrast, 98-100% of D. magna died within 96h after exposure to 600mg/L as CaCO3 water hardness and 420mg/L as CaCO3 alkalinity (LT50 of 60h with a 95% CI of 54.2-66.0h). In this treatment, a CaCO3 (calcite) precipitate formed in the water column which was ingested by and thoroughly coated the D. magna. Calcite collected from a mining impacted stream contained embedded organisms, suggesting field streams may also experience similar conditions and possibly increased mortality as observed in the lab tests. Although further investigation is required to determine the exact fate of aquatic organisms exposed to rapid calcite precipitation in the field, we caution that negative effects may occur more quickly or at lower concentrations of water hardness and alkalinity in which we observed effects in D. magna, because some species, such as aquatic insects, are more sensitive than cladocerans to changes in ionic strength. Our results provide evidence that both calcite precipitation and the major ion balance of waters should be managed in industrially affected ecosystems and we support the development of a hardness+alkalinity guideline for the protection of aquatic life. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis.

Science.gov (United States)

Nakamura, Hiromasa; Yamaguchi, Hiroki; Takagaki, Masami; Kadowaki, Tasuku; Nakao, Tatsuya; Amano, Atsushi

2015-03-01

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm(2) m(-2), has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus. Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m(2)) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery. Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm(2) m(-2). Moderate mismatch, defined as effective orifice area index ≤0.85 cm(2) m(-2), developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe. Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Comet Assay on Daphnia magna in eco-genotoxicity testing.

Science.gov (United States)

Pellegri, Valerio; Gorbi, Gessica; Buschini, Annamaria

2014-10-01

Detection of potentially hazardous compounds in water bodies is a priority in environmental risk assessment. For the evaluation and monitoring of water quality, a series of methodologies may be applied. Among them, the worldwide used toxicity tests with organisms of the genus Daphnia is one of the most powerful. In recent years, some attempts were made to utilize Daphnia magna in genotoxicity testing as many of the new environmental contaminants are described as DNA-damaging agents in aquatic organisms. The aim of this research was to develop a highly standardized protocol of the Comet Assay adapted for D. magna, especially regarding the isolation of cells derived from the same tissue (haemolymph) from newborn organisms exposed in vivo. Several methods for haemolymph extraction and different Comet Assay parameters were compared. Electrophoretic conditions were adapted in order to obtain minimum DNA migration in cells derived from untreated organisms and, at the same time, maximum sensitivity in specimens treated with known genotoxicants (CdCl2 and H2O2). Additional tests were performed to investigate if life-history traits of the cladoceran (such as the age of adult organisms that provide newborns, the clutch size of origin, the number of generations reared in standard conditions) and the water composition as well, might influence the response of the assay. This study confirms the potential application of the Comet Assay in D. magna for assessing genotoxic loads in aqueous solution. The newly developed protocol could integrate the acute toxicity bioassay, thus expanding the possibility of using this model species in freshwater monitoring (waters, sediment and soil elutriates) and is in line with the spirit of the EU Water Framework Directive in reducing the number of bioassays that involve medium-sized species. Copyright © 2014 Elsevier B.V. All rights reserved.

Toxicity of noradrenaline, a novel anti-biofouling component, to two non-target zooplankton species, Daphnia magna and Ceriodaphnia dubia.

Science.gov (United States)

Overturf, C L; Wormington, A M; Blythe, K N; Gohad, N V; Mount, A S; Roberts, A P

2015-05-01

Noradrenaline (NA) is the active component of novel antifouling agents and acts by preventing attachment of fouling organisms. The goal of this study was to examine the toxicity of NA to the non-target zooplankton D. magna and C. dubia. Neonates were exposed to one of five concentrations of NA and effects on survival, reproduction and molting were determined. Calculated LC50 values were determined to be 46 and 38 μM in C. dubia and D. magna, respectively. A 10-day C. dubia study found that reproduction metrics were significantly impacted at non-lethal concentrations. In D. magna, concentrations greater than 40 μM significantly impacted molting. A toxicity test was conducted with D. magna using oxidized NA, which yielded similar results. These data indicate that both NA and oxidized NA are toxic to non-target zooplankton. Results obtained from this study can be used to guide future ecological risk assessments of catecholamine-based antifouling agents. Copyright © 2015. Published by Elsevier Inc.

Performance Evaluation of Manual and Automated (MagNA Pure Nucleic Acid Isolation in HPV Detection and Genotyping Using Roche Linear Array HPV Test

Directory of Open Access Journals (Sweden)

Aikaterini Chranioti

2011-01-01

Full Text Available Nucleic acids of human papillomavirus (HPV isolated by manual extraction method (AmpliLute and automated MagNA pure system were compared and evaluated with cytohistological findings in 253 women. The concordance level between AmpliLute and MagNA was very good 93.3% (=0.864, <.0001. Overall HPVpositivity detected by AmpliLute was 57.3% (30.4% as single and 27% as multiple infections in contrast to MagNA 54.5% (32% and 23%, resp.. Discrepant results observed in 25 cases: 11 MagNA(−/AmpliLute(+, 10 of which had positive histology; 5 MagNA(+/AmpliLute(− with negative histology; 8 MagNA(+/AmpliLute(+: in 7 of which AmpliLute detected extra HPV genotypes and 1 MagNA(invalid/AmpliLute(+ with positive histology. Both methods performed well when compared against cytological (area under curve (AUC of AmpliLute 0.712 versus 0.672 of MagNA and histological diagnoses (AUC of AmpliLute 0.935 versus 0.877 of MagNA, with AmpliLute showing a slightly predominance over MagNA. However, higher sensitivities, specificities, and positive/negative predictive values were obtained by AmpliLute.

Sports Mega-Events: Reflections About the Legacies of Uefa Euro Cup

Directory of Open Access Journals (Sweden)

Fillipe Soares Romano

2016-01-01

Full Text Available This essay conducted a literature review of the legacy of sports mega-events, emphasizing the UEFA European Championship. In order to review the academic literature about the subject, we used the following keywords: legacies; sports mega-events and its legacies; UEFA European Championship; and their corresponding terms in Spanish and Portuguese. It was also reviewed some important research basis: Annals; BVS; DOAJ; EBSCO; REDALYC; Periódicos CAPES; PubMed; Scielo; Scopus; Science Direct; and, Scholar Google. The results were analyzed by categories. Regarding the sport mega-event Eurocopa, it was found that the tourism legacies, the economics impacts and the social aspect have been discussed more often, as well as projections and predictions of events that will occur later. It was also concluded that most of the articles shows an absence of discussion about the negative impacts of sports mega-events. It is therefore recommended to use standard methods with comparisons of results and longitudinal studies to better understand the impacts and the use of legacy.

Evaluation of Daphnia magna as an indicator of Toxicity and ...

African Journals Online (AJOL)

Performance evaluation of wastewater treatment plants (WWTPs) with special reference to toxicity reduction using Daphnia magna straus as test organism is very important to study the likely adverse effects of the treated wastewater on the aquatic ecosystem of receiving waters and to detect common environmentally ...

Trophic transfer of gold nanoparticles from Euglena gracilis or Chlamydomonas reinhardtii to Daphnia magna

International Nuclear Information System (INIS)

Lee, Woo-Mi; Yoon, Sung-Ji; Shin, Yu-Jin; An, Youn-Joo

2015-01-01

Understanding the trophic transfer of nanoparticles (NPs) is important because NPs are small enough to easily penetrate into organisms. In this study, we evaluated the trophic transfer of gold NPs (AuNPs) within the aquatic food chain. We observed AuNPs transfer from 2 species of primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna). Also, bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. The reasons for the difference in Au accumulation may be the physical structure of these organisms, and the surface area that is available for interaction with NPs. C. reinhardtii has a cell wall that may act as a barrier to the penetration of NPs. The size of E. gracilis is larger than that of C. reinhardtii. This study demonstrates the trophic transfer of AuNPs from a general producer to a consumer in an aquatic environment. - Highlights: • This study evaluated the trophic transfer of AuNPs in an aquatic food chain. • Chlamydomonas reinhardtii and Euglena gracilis were selected as the primary producers. • Daphnia magna was used as the primary consumer. • The bioaccumulation of AuNPs in E. gracilis was higher than that in C. reinhardtii. • AuNPs were transferred from C. reinhardtii and E. gracilis to D. magna. - Gold nanoparticles can transfer from primary producers (Chlamydomonas reinhardtii or Euglena gracilis) to the primary consumer (Daphnia magna) in an aquatic environment

Effects of symbiotic bacteria on chemical sensitivity of Daphnia magna.

Science.gov (United States)

Manakul, Patcharaporn; Peerakietkhajorn, Saranya; Matsuura, Tomoaki; Kato, Yasuhiko; Watanabe, Hajime

2017-07-01

The crustacean zooplankton Daphnia magna has been widely used for chemical toxicity tests. Although abiotic factors have been well documented in ecotoxicological test protocols, biotic factors that may affect the sensitivity to chemical compounds remain limited. Recently, we identified symbiotic bacteria that are critical for the growth and reproduction of D. magna. The presence of symbiotic bacteria on Daphnia raised the question as to whether these bacteria have a positive or negative effect on toxicity tests. In order to evaluate the effects of symbiotic bacteria on toxicity tests, bacteria-free Daphnia were prepared, and their chemical sensitivities were compared with that of Daphnia with symbiotic bacteria based on an acute immobilization test. The Daphnia with symbiotic bacteria showed higher chemical resistance to nonylphenol, fenoxycarb, and pentachlorophenol than bacteria-free Daphnia. These results suggested potential roles of symbiotic bacteria in the chemical resistance of its host Daphnia. Copyright © 2017 Elsevier Ltd. All rights reserved.

DEGRADATION AND CONSERVATION OF MARBLE IN THE GREEK ROMAN HADRIANIC BATHS IN LEPTIS MAGNA, LIBYA

OpenAIRE

Nabil.A. ABD EL-TAWAB

2012-01-01

The Hadrianic Baths is one of the most important archaeological sites in Leptis Magna- Libya. It was built at the command of Emperor Hadrian in the early 2nd century CE; they represent some of the most lavish structures of Leptis Magna. It is unique in design and building technique. It was built of limestone, marble and brick. This paper mainly describes the deterioration of marble. The marble in the monuments can be classified into several types, based on its color, texture, chemical composi...

Mega-events in India, Brazil, and South Africa: Lessons for safer cities

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

2016-12-13

Dec 13, 2016 ... Hosting global events is a popular strategy for boosting city profiles and spurring economic development. But these mega-events produce winners and losers, as infrastructure projects and private sector development compete for space in established neighbourhoods. Most research on mega-events has ...

Indian manpower for mega nuclear project

CERN Multimedia

2003-01-01

"India is supplying critical scientific manpower and high-tech components needed for building a Large Hadron Collider (LHC) - an accelerator used in particle physics research - a mega scientific project of the European Organisation for Nuclear Research (CERN) worth billions of dollars" (1/2 page).

Unemployment, Entrepreneurial Education and Mega Universities ...

African Journals Online (AJOL)

Individuals acquire education for two broad fundamental reasons, as an investment and as consumption. The investment function of education has continued to create tension for job search leading to cases of unemployment. Entrepreneurship education and establishment of mega universities have being identified as ...

Quantifying sublethal effects of glyphosate and Roundup® to Daphnia magna using a fluorescence based enzyme activity assay and video tracking

DEFF Research Database (Denmark)

Roslev, Peter; R. Hansen, Lone; Ørsted, Michael

Glyphosate (N-(phosphonomethyl)glycine) is the active ingredient in a range of popular broad-spectrum, non-selective herbicide formulations. The toxicity of this herbicide to non-target aquatic organisms such as Daphnia magna is often evaluated using conventional toxicity assays that focus...... on endpoints such as immobility and mortality. In this study, we investigated sublethal effects of glyphosate and Roundup® to D. magna using video tracking for quantifying behavioral changes, and a novel fluorescence based assay for measuring in vivo hydrolytic enzyme activity (FLEA assay). Roundup® exposure...... resulted in concentration-dependent inhibition of alkaline phosphatase activity in D. magna. The inhibition of alkaline phosphatase by Roundup® was temperature-dependent with lowest inhibition at 14 °C and greater inhibition at 20 and 26 °C. Exposure of D. magna to sublethal concentrations of glyphosate...

Mega-events in India, Brazil, and South Africa: Lessons for safer cities

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

13 déc. 2016 ... Hosting global events is a popular strategy for boosting city profiles and spurring economic development. But these mega-events produce winners and losers, as infrastructure projects and private sector development compete for space in established neighbourhoods. Most research on mega-events has ...

Brain abnormalities among the mentally retarded prenatally exposed atomic bomb survivors

International Nuclear Information System (INIS)

Schull, W.J.; Otake, Masanori; Nishitani, Hiromu; Hasuo, Kanehiro; Kobayashi, Takuro; Goto, Ikuo.

1992-07-01

An increased occurrence of severe mental retardation, with or without accompanying small head size, at specific gestational ages has been the most conspicuous effect on brain development of prenatal exposure to the bombings of Hiroshima and Nagasaki. A variety of biological mechanisms could be responsible for this finding, including cell killing and mismanaged neuronal migration. We describe here the findings on magnetic resonance imaging of the brains of five of these mentally retarded individuals, all of whom were exposed in the 8th through the 15th weeks following fertilization, the gestational period shown to be the most vulnerable to radiation-related damage. In the two cases exposed at the 8th or 9th week following fertilization, large areas of ectopic gray matter are seen, strong evidence of a failure of the neurons to migrate to their proper functional sites. The two individuals exposed in the 12th or 13th week show no readily recognized ectopic gray areas but do show mild macrogyria, which implies some impairment in the development of the cortical zone. Moreover, both have mega cisterna magna. Finally, the one individual seen who was exposed still later in development, in the 15th week, shows none of the changes seen in the other four individuals. This person's brain, though small, appears to have normal architecture. These findings are discussed in terms of the embryological events transpiring at the time of the prenatal exposure of these individuals to ionizing radiation. (author)

QUALIDADE DA ÁGUA DE CHUVA ARMAZENADA EM CISTERNAS RURAIS E AS MODIFICAÇÕES DECORRENTES DO MANUSEIO NA REGIÃO DE SERRINHA-BA.

Directory of Open Access Journals (Sweden)

Maria Auxiliadora Freitas dos Santos

2015-01-01

Full Text Available No nordeste brasileiro, em especial, nas áreas áridas, a escassez de água para o consumohumano constitui-se uma realidade comum. Dentre as propostas de aproveitamento,utilização e armazenamento da água da chuva, tem-se as cisternas rurais. Este trabalhoteve como objetivo avaliar a qualidade da água da chuva armazenada em cisternas ruraisassociada às práticas de manuseio realizadas pelas famílias no município deSerrinha/BA. No período de outubro/2007 a janeiro/2008 foram realizadas análisesbacteriológicas e físico-químicas das amostras de água armazenadas nas cisternas,associando-as aos dados relacionados sobre captação armazenamento, uso e manuseiodesta água através da aplicação de formulário. Os resultados demonstraram que, emrelação aos parâmetros bacteriológicos, todas as amostras apresentaram E.c. Quanto aosparâmetros físico-químicos, aqueles que estavam fora dos limites estabelecidos pelaportaria n518/04, foram: 27,8% em relação a cor, 4,2% em relação a turbidez. Emrelação aos parâmetros pH, sulfato, dureza, alcalinidade, cloreto, sólidos dissolvidos,nitrito e nitrato as amostras estão em conformidade com a portaria citada. Foramidentificadas algumas práticas de armazenamento e manuseio que proporcionam acontaminação da água, dentre elas: 44,4% das famílias entrevistadas misturam a água dachuva com água de outras fontes, 11,2% não desviam a primeira água da chuva, 27,8 %insere peixes na água e deste percentual, 20% fornece alimento. Para captar a água,70,8% das famílias utilizam o balde. A utilização de práticas inadequadas possibilitou oaumento da concentração de E.c e entre as famílias que apenas utilizam a bombamanual foram encontrados os menores valores de E.c. As cisternas constituem umatecnologia viável para o abastecimento de água no nordeste brasileiro, entretanto, asfamílias devem aperfeiçoar as técnicas de manejo, dentre elas realizar a desinfecção daágua da chuva

Persistent dural cerebrospinal fluid leak shown by retrograde radionuclide myelography: case report

International Nuclear Information System (INIS)

Kadrie, H.; Driedger, A.A.; McInnis, W.

1976-01-01

Following inadvertent spinal anesthesia for delivery, a patient developed incapacitating post-lumbar puncture headache that persisted for 9 weeks. Scintigrams of the lumbar region, obtained after injection of /sup 99m/Tc-human serum albumin into the cisterna magna, showed the cerebrospinal fluid leak. Blood patch repair was carried out, with immediate relief of all symptoms. Because of subsequent atypical headaches, a second cisternogram was done by the same technique. This study confirmed that there was no further dural leak, and other evidence indicated that the recurrent headache was related to functional problems

Quantitative Gd-DOTA uptake from cerebrospinal fluid into rat brain using 3D VFA-SPGR at 9.4T

DEFF Research Database (Denmark)

Lee, Hedok; Mortensen, Kristian; Sanggaard, Simon

2017-01-01

strategies for accurate 3D contrast concentration mapping at 9.4T were developed and whole brain dynamic concentration maps were derived to study solute transport via the glymphatic system. The newly developed approach will enable future quantitative studies of the glymphatic system in health and disease...... phantoms. Normal Wistar rats underwent Gd-DOTA infusion into CSF via the cisterna magna and continuous MRI for approximately 130 min using T1-weighted imaging. Dynamic Gd-DOTA concentration maps were calculated and parenchymal uptake was estimated. RESULTS: In the phantom study, T1 discrepancies between...

High pathogenicity and strong immunogenicity of a Chinese isolate of Eimeria magna Pérard, 1925.

Science.gov (United States)

Tao, Geru; Wang, Yunzhou; Li, Chao; Gu, Xiaolong; Cui, Ping; Fang, Sufang; Suo, Xun; Liu, Xianyong

2017-06-01

Coccidia infection of rabbits with one or several species of parasites of the genus Eimeria causes coccidiosis, a disease leading to huge economic losses in the rabbit industry. Eimeria magna, one of the causal agents of rabbit coccidiosis, was characterized as mildly pathogenic and moderately immunogenic in previous studies. In this study, we identified a Chinese isolate of E. magna by testing its biological features (oocyst morphology and size, prepatent time) and sequencing its internal transcribed spacer 1 (ITS-1) DNA fragment. This isolate is highly pathogenic; infection of rabbits with only 1×10 2 oocysts caused a 55% reduction in weight gain in 14days. In addition, immunization with 1×10 2 oocysts prevented body weight loss against re-infection with 5×10 4 oocysts, indicating the high immunogenicity of this isolate. Our study described the distinctive phenotype of the Chinese isolate of E. magna and contributed to the research of geographic variation of rabbit coccidia. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioavailability and effect of pirimicarb on Daphnia magna in a laboratory freshwater/sediment system

DEFF Research Database (Denmark)

Kusk, K.O.

1996-01-01

In tests with newborn and one-week-old Daphnia magna, 48-h EC(50) values of 21-24 mu g/L and 16 mu g/L pirimicarb, respectively, were found. Older animals thus were as sensitive to pirimicarb as newborn animals. In an experiment with sediment included in the test system, all mother animals survived...... not reduced significantly during the experiment, due to the small amount of sediment used. Accumulation in the sediment was found independent of the water concentration used. This was also the case with bioaccumulation in Daphnia magna, where a bioaccumulation factor of 31-37 was found on a dry weight basis...

Comparative effects of graphene and graphene oxide on copper toxicity to Daphnia magna: Role of surface oxygenic functional groups.

Science.gov (United States)

Liu, Yingying; Fan, Wenhong; Xu, Zhizhen; Peng, Weihua; Luo, Shenglian

2018-05-01

Although the risk of graphene materials to aquatic organisms has drawn wide attention, the combined effects of graphene materials with other contaminants such as toxic metals, which may bring about more serious effects than graphene materials alone, have seldom been explored. Herein, the effects of graphene (GN) and graphene oxide (GO, an important oxidized derivative of graphene) on copper (Cu) toxicity to Daphnia magna were systematically investigated. The results indicated that GN remarkably increased the Cu accumulation in D. magna and enhanced the oxidative stress injury caused by Cu, whereas did not significantly alter D. magna acute mortality within the tested Cu concentrations (0-200 μg L -1 ). On the contrary, GO significantly decreased the Cu accumulation in D. magna and alleviated the oxidative stress injury caused by Cu. Meanwhile, the presence of GO significantly reduced the mortality of D. magna when Cu concentration exceeded 50 μg L -1 . The different effects of GN and GO on Cu toxicity were possibly dependent on the action of surface oxygenic functional group. Because of the introduction of surface oxygenic functional groups, the adsorption ability to metal ions, stability in water and interaction mode with organisms of GO are quite different from that of GN, causing different effects on Cu toxicity. This study provides important information on the bioavailability and toxicity of heavy metals as affected by graphene materials in natural water. Copyright © 2017 Elsevier Ltd. All rights reserved.

When is a Tsunami a Mega-Tsunami?

Science.gov (United States)

Chague-Goff, C.; Goff, J. R.; Terry, J. P.; Goto, K.

2014-12-01

The 2004 Indian Ocean Tsunami is commonly called a mega-tsunami, and this attribute has also been linked to the 2011 Tohoku-oki tsunami. However, since this term was first coined in the early 1990's there have been very few attempts to define it. As such it has been applied in a rather arbitrary fashion to a number of tsunami characteristics, such as wave height or amplitude at both the source and at distant locations, run-up height, geographical extent and impact. The first use of the term is related to a tsunami generated by a large bolide impact and indeed it seems entirely appropriate that the term should be used for such rare events on geological timescales. However, probably as a result of media-driven hyperbole, scientists have used this term at least twice in the last decade, which is hardly a significant portion of the geological timescale. It therefore seems reasonable to suggest that these recent unexpectedly large events do not fall in the category of mega-tsunami but into a category of exceptional events within historical experience and local perspective. The use of the term mega-tsunami over the past 14 years is discussed and a definition is provided that marks the relative uniqueness of these events and a new term, appropriately Japanese in origin, namely that of souteigai-tsunami, is proposed. Examples of these tsunamis will be provided.

Characterization of the particulate air pollution in contrasted mega cities

International Nuclear Information System (INIS)

Favez, O.

2008-02-01

This work aims at characterizing the physics and the chemistry that govern particulate air pollution in two mega cities (Paris and Cairo) for which the size distribution and the chemical composition of airborne particles were poorly documented. Seasonal variations of the main aerosol sources and transformation processes are investigated in these two urban centres, with a particular attention to semi-volatile material and secondary organic aerosols. Short-term health effects of Paris size-segregated aerosols, as well as particulate pollution during the Cairo 'Black Cloud' season, are also emphasized here. Finally, the comparison of results obtained for the two mega cities and for another one (Beijing) allows investigating main factors responsible for particulate air pollution in urban centres with contrasted climatic conditions and development levels. Notably, this work also allows the build-up of an experimental dataset which is now available for the modelling of urban air quality and of environmental impacts of mega city air pollution. (author)

Asteroids from a Martian Mega Impact

Science.gov (United States)

Kohler, Susanna

2018-04-01

Like evidence left at a crime scene, the mineral olivine may be the clue that helps scientists piece together Marss possibly violent history. Could a long-ago giant impact have flung pieces of Mars throughout our inner solar system? Two researchers from the Tokyo Institute of Technology in Japan are on the case.A Telltale MineralOlivine, a mineral that is common in Earths subsurface but weathers quickly on the surface. Olivine is a major component of Marss upper mantle. [Wilson44691]Olivine is a major component of the Martian upper mantle, making up 60% of this region by weight. Intriguingly, olivine turns up in other places in our solar system too for instance, in seven out of the nine known Mars Trojans (a group of asteroids of unknown origin that share Marss orbit), and in the rare A-type asteroids orbiting in the main asteroid belt.How did these asteroids form, and why are they so olivine-rich? An interesting explanation has been postulated: perhaps this olivine all came from the same place Mars as the result of a mega impact billions of years ago.Evidence for ImpactMars bears plenty of signs pointing to a giant impact in its past. The northern and sourthern hemispheres of Mars look very different, a phenomenon referred to as the Mars hemisphere dichotomy. The impact of a Pluto-sized body could explain the smooth Borealis Basin that covers the northern 40% of Marss surface.This high-resolution topographic map of Mars reveals the dichotomy between its northern and sourthern hemispheres. The smooth region in the northern hemisphere, the Borealis basin, may have been formed when a giant object impacted Mars billions of years ago. [NASA/JPL/USGS]Other evidence piles up: Marss orbit location, its rotation speed, the presence of its two moons all could be neatly explained by a large impact around 4 billion years ago. Could such an impact have also strewn debris from Marss mantle across the solar system?To test this theory, we need to determine if a mega impact is

Uptake and effects of microplastic textile fibers on freshwater crustacean Daphnia magna.

Science.gov (United States)

Jemec, Anita; Horvat, Petra; Kunej, Urban; Bele, Marjan; Kržan, Andrej

2016-12-01

Microplastic fibers (MP) from textile weathering and washing are increasingly being recognized as environmental pollutants. The majority of studies on the bioavailability and effects of microplastic focused on small polystyrene spherical plastic particles, while less data are available for fibers and for other materials besides polystyrene. We investigated the ingestion and effects of ground polyethylene terephthalate (PET) textile microfibers (length range: 62-1400 μm, width 31-528 μm, thickness 1-21.5 μm) on the freshwater zooplankton crustacean Daphnia magna after a 48 h exposure and subsequent 24 h of recovery in MP free medium and algae. The majority of ingested fibers by D. magna were around 300 μm, but also some very large twisted MP fibers around 1400 μm were found inside the gut. Exposure to these fibers results in increased mortality of daphnids after 48 h only in the case where daphnids were not pre-fed with algae prior to experiment, but no effect was found when daphnids were fed before the experiments. Regardless of the feeding regime, daphnids were not able to recover from MP exposure after additional 24 h incubation period in a MP free medium with algae. The uptake and effects of PET textile MP on D. magna are presented here for the first time. Copyright © 2016 Elsevier Ltd. All rights reserved.

Applicability of "MEGA"[Eighth Note] to Sexually Abusive Youth with Low Intellectual Functioning

Science.gov (United States)

Miccio-Fonseca, L. C.; Rasmussen, Lucinda A.

2013-01-01

The study explored the predictive validity of "Multiplex Empirically Guided Inventory of Ecological Aggregates for Assessing Sexually Abusive Children and Adolescents (Ages 4 to 19)" ("MEGA"[eighth note]; Miccio-Fonseca, 2006b), a comprehensive developmentally sensitive risk assessment outcome tool. "MEGA"[eighth note] assesses risk for coarse…

Governance and institutions of transportation investments in U.S. mega-regions

Directory of Open Access Journals (Sweden)

H. L. Vega

2008-09-01

Full Text Available From a planning perspective, a mega-region can be defined as an extended network of metropolitan centers and their surrounding areas, crossing county and state lines, linked by integrated labor markets, land use systems and transportation and communication infrastructure. From a governance perspective, delimiting the jurisdictional borders of a mega-region is rather challenging due to the overlap of hierarchy of governance systems. It has been suggested that the effective management of existing transportation infrastructure and the planning and financing of new investments in these areas will need to operate under a regional framework of governance. What such regional framework might look like is still subject to debate. Despite years in the planning, currently no mega-regional transportation initiative has been implemented in the U.S. This article uses descriptive and interpretative analysis to further the debate in two areas. It first reviews definitional issues in the existing literature as they apply to mega-regions and transportation. Second, it undertakes a comprehensive survey of regional initiatives, such as the Corridors of the Future Program, to highlight the complexity of multi-state transportation projects. Lessons from this survey can be useful when developing future transport policy, as policymakers increase their efforts to adopt regional governance initiatives to finance transportation investments worldwide.

Mega hub for intermodal transport - the planning of the most advanced container terminal in the world; Mega-Drehscheibe fuer den Kombinierten Verkehr - Planung des modernsten Containerbahnhofes der Welt

Energy Technology Data Exchange (ETDEWEB)

Franke, K.P. [Noell Stahl- und Maschinenbau GmbH, Wuerzburg (Germany). Abt. Hafentechnik

1998-12-31

The introduction of innovative mega hub systems for the operation of cargo trains is a promising starting point for increasing the efficiency of intermodal transport. A first mega hub as it is known has been planned for Northern Germany with its centre in Lehrte near Hannover. Instead of shunting the waggons, containers will be transferred from train to train at the mega hub. This is not only faster, but also more economical and thus more attractive to rail transport clients. No other known system can achieve such high transhipment/shunting capacities per surface unit. The design of the system guarantees the maximum degree of flexibility in transhipment operations. A high degree of automation will ensure the quality and speed of transhipment. The technical development of the fast transhipment system (FTS) by Noell has been completed. (orig.) [Deutsch] Ein vielversprechender Ansatz fuer die Steigerung der Leistungsfaehigkeit des Kombinierten Verkehrs (KV) ist die Einfuehrung von innovativen Drehscheibensystemen fuer den Betrieb der Cargo-Zuege. Eine erste sogenannte Mega-Drehscheibe wurde fuer den Norden Deutschlands mit Zentrum Lehrte bei Hannover geplant. Statt zu rangieren sollen in der Mega-Drehscheibe die Behaelter zwischen den Zuegen umsteigen. Das ist schneller, kostenguenstiger und damit attraktiver fuer den Bahnkunden. Darueber hinaus ist kein System bekannt, bei dem eine so hohe Umschlag-/Umstelleistung je Flaecheneinheit realisiert werden kann. Die Gestaltung der Anlage gewaehrt eine maximale Flexibilitaet im Umschlagbetrieb. Ein hoher Automatisierungsgrad wird Qualitaet und Schnelligkeit des Umschlages sichern. Die technische Entwicklung der Schnellumschlagtechnik seitens Noell ist abgeschlossen. (orig.)

Qualitative Approach on Investigating Failure Factors of Yemeni Mega Construction Projects

OpenAIRE

Gamil Yaser; Abdul Rahman Ismail; Nagapan Sasitharan; Alemad Nashwan

2017-01-01

Large construction projects in Yemen face many impediments and challenges to be completed successfully. This article presents an investigative cases study of three mega construction projects which are considered failed to achieve their assigned plans and objectives. An exploratory interview was implied in this study via telephone to three construction experts who involved directly in these mega projects at the managerial level. Semi-structured questions based on literature were designed as gu...

Mesozoic evolution of the Tisza Mega-unit

Science.gov (United States)

Haas, János; Péró, Csaba

The south-eastern part of the basement of the Pannonian Basin is made up of Variscan crystalline complexes and early Mesozoic formations showing striking affinity with the corresponding formations in the southern margin of the European Plate. This large composite structural unit, which is actually an exotic terrane of European Plate origin, has been named the Tisza Mega-unit. Based upon relevant data of the pre-Tertiary basement of southern Hungary the reconstruction of the position of the Tisza Terrane in the early Alpine evolutionary stages, the process of its separation and break-off from the European Plate, and results of its Eo-Alpine deformations are summarised in the present paper. In the Variscan and early Alpine evolutionary stages the area of the later Tisza Mega-unit was located at the margin of the European Plate. During Variscan orogeny terrane accretion led to intensive deformation and metamorphism in this belt. This was followed by transpressional tectonics and the development of molasse basins in the late and post-Variscan stages, and passive margin evolution after the Neotethys opening in the Middle Triassic. The separation of the Tisza Mega-unit began with incipient continental rifting along the axis of the later Ligurian-Penninic-Vahic oceanic branch in the Late Triassic. The end of terrigenous material deposition in the most external zones, and a coeval change in fossil assemblage, point to the separation of the Tisza Block from the European Plate in the Early Bathonian. Significant rotation of the Tisza Mega-unit and coeval paroxysm of alkaline rift-type basalt volcanism took place in the Early Cretaceous. In the mid-Cretaceous, due to the northward motion of the Adria Block and the related closure of the westernmost Neotethys basin, the extensional regime changed to a compressional one, leading to onset of the nappe stacking and low-grade regional metamorphism within the Tisza microplate. In the foreland of the nappe systems flexural basins

Genetically modified rice Bt-Shanyou63 expressing Cry1Ab/c protein does not harm Daphnia magna.

Science.gov (United States)

Zhang, Li; Guo, Ruqing; Fang, Zhixiang; Liu, Biao

2016-10-01

The genetically modified (GM) rice Bt-ShanYou63 (Bt-SY63) received an official biosafety certificate while its safety remained in dispute. In a lifelong study, Daphnia magna were experimentally fed a basal diet of rice flours from Bt-SY63 or its parental rice ShanYou63 (SY63) at concentrations of 0.2mg, 0.3mg, or 0.4mgC (per individual per day). Overall the survival, body size, and reproduction of the animals were comparable between Bt-SY63 and ShanYou63.. The results showed that no significant differences were observed in growth and reproduction parameters between D. magna fed GM and non-GM flour and no dose-related changes occurred in all the values. Based on the different parameters assessed, the GM rice Bt-SY63 is a safe food source for D. magna that does not differ in quality from non-GM rice. Copyright © 2016. Published by Elsevier Inc.

Acute and Chronic Toxicity of Soluble Fractions of Industrial Solid Wastes on Daphnia magna and Vibrio fischeri

Directory of Open Access Journals (Sweden)

Letícia Flohr

2012-01-01

Full Text Available Industrial wastes may produce leachates that can contaminate the aquatic ecosystem. Toxicity testing in acute and chronic levels is essential to assess environmental risks from the soluble fractions of these wastes, since only chemical analysis may not be adequate to classify the hazard of an industrial waste. In this study, ten samples of solid wastes from textile, metal-mechanic, and pulp and paper industries were analyzed by acute and chronic toxicity tests with Daphnia magna and Vibrio fischeri. A metal-mechanic waste (sample MM3 induced the highest toxicity level to Daphnia magna(CE50,48 h=2.21%. A textile waste induced the highest toxicity level to Vibrio fischeri (sample TX2, CE50,30 min=12.08%. All samples of pulp and paper wastes, and a textile waste (sample TX2 induced chronic effects on reproduction, length, and longevity of Daphnia magna. These results could serve as an alert about the environmental risks of an inadequate waste classification method.

Biochemical analysis of plant protection afforded by a nonpathogenic endophytic mutant of Colletotrichum magna

Energy Technology Data Exchange (ETDEWEB)

Redman, R.S.; Rodriguez, R.J. (Geological Survey, Seattle, WA (United States) Univ. of Washington, Seattle, WA (United States). Dept. of Botany); Clifton, D.R.; Morrel, J.; Brown, G. (Geological Survey, Seattle, WA (United States)); Freeman, S. (Volcani Center, Bet Dagan (Israel). Dept. of Plant Pathology)

1999-02-01

A nonpathogenic mutant of Colletotrichum magna (path-1) was previously shown to protect watermelon (Citrullus lanatus) and cucumber (Cucumis sativus) seedlings from anthracnose disease elicited by wild-type C. magna. Disease protection was observed in stems of path-1-colonized cucurbits but not in cotyledons, indicating that path-1 conferred tissue-specific and/or localized protection. Plant biochemical indicators of a localized and systemic (peroxidase, phenylalanine ammonia-lyase, lignin, and salicylic acid) plant-defense response were investigated in anthracnose-resistant and-susceptible cultivars of cucurbit seedlings exposed to four treatments: (1) water (control), (2) path-1 conidia, (3) wild-type conidia, and (4) challenge conditions (inoculation into path-1 conidia for 48 h and then exposure to wild-type conidia). Collectively, these analyses indicated that disease protection in path-1-colonized plants was correlated with the ability of these plants to mount a defense response more rapidly and to equal or greater levels than plants exposed to wild-type C. magna alone. Watermelon plants colonized with path-1 were also protected against disease caused by Colletotrichum orbiculare and Fusarium oxysporum. A model based on the kinetics of plant-defense activation is presented to explain the mechanism of path-1-conferred disease protection.

Daphnia magna fitness during low food supply under different water temperature and brownification scenarios

Directory of Open Access Journals (Sweden)

Andrea Gall

2016-11-01

Full Text Available Much of our current knowledge about non-limiting dietary carbon supply for herbivorous zooplankton is based on experimental evidence and typically conducted at ~1 mg C L-1 and ~20°C. Here we ask how low supply of dietary carbon affects somatic growth, reproduction, and survival of Daphnia magna and test effects of higher water temperature (+3 °C relative to ambient and brownification (3X higher than natural water color; both predicted effects of climate change during fall cooling. We predicted that even at very low carbon supply (~5µg C L-1, higher water temperature and brownification will allow D. magna to increase its fitness. Neonates (<24 h old were incubated with lake seston for 4 weeks (October-November 2013 in experimental bottles submerged in outdoor mesocosms to explore effects of warmer and darker water. Higher temperature and brownification did not significantly affect food quality, as assessed by its fatty acid composition. Daphnia exposed to both increased temperature and brownification had highest somatic growth and were the only that reproduced, and higher temperature caused the highest Daphnia survival success. These results suggest that even under low temperature and thus lower physiological activity, low food quantity is more important than its quality for D. magna fitness.

CRISPR/Cas-mediated knock-in via non-homologous end-joining in the crustacean Daphnia magna.

Science.gov (United States)

Kumagai, Hitoshi; Nakanishi, Takashi; Matsuura, Tomoaki; Kato, Yasuhiko; Watanabe, Hajime

2017-01-01

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system (Cas) is widely used for mediating the knock-in of foreign DNA into the genomes of various organisms. Here, we report a process of CRISPR/Cas-mediated knock-in via non-homologous end joining by the direct injection of Cas9/gRNA ribonucleoproteins (RNPs) in the crustacean Daphnia magna, which is a model organism for studies on toxicology, ecology, and evolution. First, we confirmed the cleavage activity of Cas9 RNPs comprising purified Cas9 proteins and gRNAs in D. magna. We used a gRNA that targets exon 10 of the eyeless gene. Cas9 proteins were incubated with the gRNAs and the resulting Cas9 RNPs were injected into D. magna eggs, which led to a typical phenotype of the eyeless mutant, i.e., eye deformity. The somatic and heritable mutagenesis efficiencies were up to 96% and 40%, respectively. Second, we tested the CRISPR/Cas-mediated knock-in of a plasmid by the injection of Cas9 RNPs. The donor DNA plasmid harboring the fluorescent reporter gene was designed to contain the gRNA recognition site. The co-injection of Cas9 RNPs together with the donor DNAs resulted in generation of one founder animal that produced fluorescent progenies. This transgenic Daphnia had donor DNA at the targeted genomic site, which suggested the concurrent cleavage of the injected plasmid DNA and genomic DNA. Owing to its simplicity and ease of experimental design, we suggest that the CRISPR/Cas-mediated knock-in method represents a promising tool for studying functional genomics in D. magna.

Genes mirror geography in Daphnia magna.

Science.gov (United States)

Fields, Peter D; Reisser, Céline; Dukić, Marinela; Haag, Christoph R; Ebert, Dieter

2015-09-01

Identifying the presence and magnitude of population genetic structure remains a major consideration in evolutionary biology as doing so allows one to understand the demographic history of a species as well as make predictions of how the evolutionary process will proceed. Next-generation sequencing methods allow us to reconsider previous ideas and conclusions concerning the distribution of genetic variation, and what this distribution implies about a given species evolutionary history. A previous phylogeographic study of the crustacean Daphnia magna suggested that, despite strong genetic differentiation among populations at a local scale, the species shows only moderate genetic structure across its European range, with a spatially patchy occurrence of individual lineages. We apply RAD sequencing to a sample of D. magna collected across a wide swath of the species' Eurasian range and analyse the data using principle component analysis (PCA) of genetic variation and Procrustes analytical approaches, to quantify spatial genetic structure. We find remarkable consistency between the first two PCA axes and the geographic coordinates of individual sampling points, suggesting that, on a continent-wide scale, genetic differentiation is driven to a large extent by geographic distance. The observed pattern is consistent with unimpeded (i.e. no barriers, landscape or otherwise) migration at large spatial scales, despite the fragmented and patchy nature of favourable habitats at local scales. With high-resolution genetic data similar patterns may be uncovered for other species with wide geographic distributions, allowing an increased understanding of how genetic drift and selection have shaped their evolutionary history. © 2015 John Wiley & Sons Ltd.

Facilitators and Inhibitors of Bidding and Hosting Mega Sporting Events in Iran

Directory of Open Access Journals (Sweden)

Mohammad Koosha

2013-01-01

Full Text Available Legacies of hosting mega sporting events have been attempting idea for both the developed and the developing nations to participate in "bidding" competitions. Through mega sporting events bid process, despite all defined essentials infrastructures, the viewpoint of local organizing committee play a significant role to propose a winning bid and delivery of successful games. This research aims to identify the facilitators and inhibitors of bidding and hosting mega sporting events in Iran from the viewpoints of the Iranian distinguished professors in the sport management and the sport executive managers. Researcher questionnaire and Semi-structure interviews were conducted to gain in depth data. The results indicated that Iran currently has limitations to have winning bid and successful host mega sporting events; even though, it possesses the potential to do so. Public interest and support for hosting the sport events, good security condition against terrorism and tourist attractions are known as the strong points and he challenges and inhibitors which Iran is faced with includes: the qualitative and quantitative weakness in the transportation infrastructures and sport venues, west countries economic boycott, unstable government support and the lack of long-run planning for the events.

Assessment of the effects of the carbamazepine on the endogenous endocrine system of Daphnia magna.

Science.gov (United States)

Oropesa, A L; Floro, A M; Palma, P

2016-09-01

In the present study, the endocrine activity of the antiepileptic pharmaceutical carbamazepine (CBZ) in the crustacean Daphnia magna was assessed. To assess the hormonal activity of the drug, we exposed maternal daphnids and embryos to environmental relevant concentrations of CBZ (ranging from 10 to 200 μg/L) and to mixtures of CBZ with fenoxycarb (FEN; 1 μg/L). Chronic exposure to CBZ significantly decreased the reproductive output and the number of molts of D. magna at 200 μg/L. This compound induced the production of male offspring (12 ± 1.7 %), in a non-concentration-dependent manner, acting as a weak juvenile hormone analog. Results showed that this substance, at tested concentrations, did not antagonize the juvenoid action of FEN. Further, CBZ has shown to be toxic to daphnid embryos through maternal exposure interfering with their normal gastrulation and organogenesis stages but not producing direct embryo toxicity. These findings suggest that CBZ could act as an endocrine disruptor in D. magna as it decreases the reproductive output, interferes with sex determination, and causes development abnormality in offspring. Therefore, CBZ could directly affect the population sustainability.

MAST: a Mega Amp Spherical Tokamak

International Nuclear Information System (INIS)

Darke, A.C.; Harbar, J.R.; Hay, J.H.; Hicks, J.B.; Hill, J.W.; McKenzie, J.S.; Morris, A.W.; Nightingale, M.P.S.; Todd, T.N.; Voss, G.M.; Watkins, J.R.

1995-01-01

The highly successful tight aspect ratio tokamak research pioneered on the START machine at Culham, together with the attractive possibilities of the concept, suggest a larger device should be considered. The design of a Mega Amp Spherical Tokamak is described, operating at much higher currents and over longer pulses than START and compatible with strong additional heating. (orig.)

Male meiosis in Crustacea: synapsis, recombination, epigenetics and fertility in Daphnia magna.

Science.gov (United States)

Gómez, Rocío; Van Damme, Kay; Gosálvez, Jaime; Morán, Eugenio Sánchez; Colbourne, John K

2016-09-01

We present the first detailed cytological study of male meiosis in Daphnia (Crustacea: Branchiopoda: Cladocera)-an aquatic microcrustacean with a cyclical parthenogenetic life cycle. Using immunostaining of the testes in Daphnia magna for baseline knowledge, we characterized the different stages of meiotic division and spermiogenesis in relation to the distribution of proteins involved in synapsis, early recombination events and sister chromatid cohesion. We also studied post-translational histone modifications in male spermatocytes, in relation to the dynamic chromatin progression of meiosis. Finally, we applied a DNA fragmentation test to measure sperm quality of D. magna, with respect to levels of inbreeding. As a proxy for fertility, this technique may be used to assess the reproductive health of a sentinel species of aquatic ecosystems. Daphnia proves to be a model species for comparative studies of meiosis that is poised to improve our understanding of the cytological basis of sexual and asexual reproduction.

Parole, Sintagmatik, dan Paradigmatik Motif Batik Mega Mendung

Directory of Open Access Journals (Sweden)

Rudi - Nababan

2012-04-01

Full Text Available ABSTRACT   Discussing traditional batik is related a lot to the organization system of fine arts element ac- companying it, either the pattern of the motif or the technique of the making. In this case, the motif of Mega Mendung Cirebon certainly has patterns and rules which are traditionally different from the other motifs in other areas. Through  semiotics analysis especially with Saussure and Pierce concept, it can be traced that batik with Cirebon motif, in this case Mega Mendung motif, has parole and langue system, as unique fine arts language in batik, and structure of visual syntagmatic and paradigmatic. In the context of batik motif as fine arts language, it is surely related to sign system as symbol and icon.       Keywords: visual semiotic, Cirebon’s batik.

Mega Tsunamis of the World Ocean and Their Implication for the Tsunami Hazard Assessment

Science.gov (United States)

Gusiakov, V. K.

2014-12-01

Mega tsunamis are the strongest tsunamigenic events of tectonic origin that are characterized by run-up heights up to 40-50 m measured along a considerable part of the coastline (up to 1000 km). One of the most important features of mega-tsunamis is their ability to cross the entire oceanic basin and to cause an essential damage to its opposite coast. Another important feature is their ability to penetrate into the marginal seas (like the Sea of Okhotsk, the Bering Sea) and cause dangerous water level oscillations along the parts of the coast, which are largely protected by island arcs against the impact of the strongest regional tsunamis. Among all known historical tsunamis (nearly 2250 events during the last 4000 years) they represent only a small fraction (less than 1%) however they are responsible for more than half the total tsunami fatalities and a considerable part of the overall tsunami damage. The source of all known mega tsunamis is subduction submarine earthquakes with magnitude 9.0 or higher having a return period from 200-300 years to 1000-1200 years. The paper presents a list of 15 mega tsunami events identified so far in historical catalogs with their basic source parameters, near-field and far-field impact effects and their generation and propagation features. The far-field impact of mega tsunamis is largely controlled by location and orientation of their earthquake source as well as by deep ocean bathymetry features. We also discuss the problem of the long-term tsunami hazard assessment when the occurrence of mega tsunamis is taken into account.

[Comparison of manual and automated (MagNA Pure) nucleic acid isolation methods in molecular diagnosis of HIV infections].

Science.gov (United States)

Alp, Alpaslan; Us, Dürdal; Hasçelik, Gülşen

2004-01-01

Rapid quantitative molecular methods are very important for the diagnosis of human immunodeficiency virus (HIV) infections, assessment of prognosis and follow up. The purpose of this study was to compare and evaluate the performances of conventional manual extraction method and automated MagNA Pure system, for the nucleic acid isolation step which is the first and most important step in molecular diagnosis of HIV infections. Plasma samples of 35 patients in which anti-HIV antibodies were found as positive by microparticule enzyme immunoassay and confirmed by immunoblotting method, were included in the study. The nucleic acids obtained simultaneously by manual isolation kit (Cobas Amplicor, HIV-1 Monitor Test, version 1.5, Roche Diagnostics) and automated system (MagNA Pure LC Total Nucleic Acid Isolation Kit, Roche Diagnostics), were amplified and detected in Cobas Amplicor (Roche Diagnostics) instrument. Twenty three of 35 samples (65.7%) were found to be positive, and 9 (25.7%) were negative by both of the methods. The agreement between the methods were detected as 91.4%, for qualitative results. Viral RNA copies detected by manual and MagNA Pure isolation methods were found between 76.0-7.590.000 (mean: 487.143) and 113.0-20.300.0000 (mean: 2.174.097) copies/ml, respectively. When both of the overall and individual results were evaluated, the number of RNA copies obtained with automatized system, were found higher than the manual method (p<0.05). Three samples which had low numbers of nucleic acids (113, 773, 857, respectively) with MagNA Pure, yielded negative results with manual method. In conclusion, the automatized MagNA Pure system was found to be a reliable, rapid and practical method for the isolation of HIV-RNA.

Automated extraction of genomic DNA from medically important yeast species and filamentous fungi by using the MagNA Pure LC system.

Science.gov (United States)

Loeffler, Juergen; Schmidt, Kathrin; Hebart, Holger; Schumacher, Ulrike; Einsele, Hermann

2002-06-01

A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (10(5) to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sensitivity when DNA was extracted manually; in 9 of 28 runs, we could achieve a higher sensitivity of 1 CFU/ml blood, which was found to be significant (p DNA from all fungal species analyzed could be extracted and amplified by real-time PCR. Negative controls from all MagNA Pure isolations remained negative. Sixty-three clinical samples showed identical results by both methods, whereas in 4 of 67 samples, discordant results were obtained. Thus, the MagNA Pure LC technique offers a fast protocol for automated DNA isolation from numerous fungi, revealing high sensitivity and purity.

Contribution of Central μ-Receptors to Switching Pulmonary C-Fibers-Mediated Rapid Shallow Breathing into An Apnea by Fentanyl in Anesthetized Rats

Science.gov (United States)

Zhang, Zhenxiong; Zhang, Cancan; Zhuang, Jianguo; Xu, Fadi

2012-01-01

Our previous study has shown that activating peripheral μ-receptors is necessary for switching the bronchopulmonary C-fibers (PCFs)-mediated rapid shallow breathing (RSB) into an apnea by systemic administration of fentanyl. The brainstem nuclei, such as the medial nucleus tractus solitarius (mNTS) and the Pre-Botzinger Complex (PBC), are required for completing the PCF-mediated respiratory reflexes. Moreover, these areas contain abundant μ-receptors and their activation prolongs expiratory duration (TE). Thus, we asked if central μ-receptors, especially those in the mNTS and PBC, are involved in fully expressing this RSB-apnea switch by fentanyl. In anesthetized rats, the cardiorespiratory responses to right atrial injection of phenylbiguanide (PBG, 3–6 μg/kg) were repeated after: 1) fentanyl (iv), a μ-receptor agonist, alone (8 μg/kg, iv); 2) fentanyl following microinjection of naloxone methiodide (NXM, an opioid receptor antagonist) into the cisterna magna (10 μg/4 μl); 3) the bilateral mNTS (10 mM, 20 nl); or 4) PBC (10 mM, 20 nl). Our results showed that PBG shortened TE by 37 ± 6 % (RSB, from 0.41 ± 0.05 to 0.26 ± 0.03 s, P fentanyl (iv). Pretreatment with NXM injected into the cisterna magna or the PBC, but not the mNTS, prevented the fentanyl-induced switch. This study, along with our previous results mentioned above, suggests that although peripheral μ-receptors are essential for triggering the fentanyl-induced switch, central μ-receptors, especially those in the PBC, are required to fully exhibit such switch. PMID:22759907

Quantitative Gd-DOTA uptake from cerebrospinal fluid into rat brain using 3D VFA-SPGR at 9.4T.

Science.gov (United States)

Lee, Hedok; Mortensen, Kristian; Sanggaard, Simon; Koch, Palle; Brunner, Hans; Quistorff, Bjørn; Nedergaard, Maiken; Benveniste, Helene

2018-03-01

We propose a quantitative technique to assess solute uptake into the brain parenchyma based on dynamic contrast-enhanced MRI (DCE-MRI). With this approach, a small molecular weight paramagnetic contrast agent (Gd-DOTA) is infused in the cerebral spinal fluid (CSF) and whole brain gadolinium concentration maps are derived. We implemented a 3D variable flip angle spoiled gradient echo (VFA-SPGR) longitudinal relaxation time (T1) technique, the accuracy of which was cross-validated by way of inversion recovery rapid acquisition with relaxation enhancement (IR-RARE) using phantoms. Normal Wistar rats underwent Gd-DOTA infusion into CSF via the cisterna magna and continuous MRI for approximately 130 min using T1-weighted imaging. Dynamic Gd-DOTA concentration maps were calculated and parenchymal uptake was estimated. In the phantom study, T1 discrepancies between the VFA-SPGR and IR-RARE sequences were approximately 6% with a transmit coil inhomogeneity correction. In the in vivo study, contrast transport profiles indicated maximal parenchymal retention of approximately 19% relative to the total amount delivered into the cisterna magna. Imaging strategies for accurate 3D contrast concentration mapping at 9.4T were developed and whole brain dynamic concentration maps were derived to study solute transport via the glymphatic system. The newly developed approach will enable future quantitative studies of the glymphatic system in health and disease states. Magn Reson Med 79:1568-1578, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Better Alone or in Ill Company? The Effect of Migration and Inter-Species Comingling on Fascioloides magna Infection in Elk.

Science.gov (United States)

Pruvot, Mathieu; Lejeune, Manigandan; Kutz, Susan; Hutchins, Wendy; Musiani, Marco; Massolo, Alessandro; Orsel, Karin

2016-01-01

Migratory movements and alteration of host communities through livestock production are examples of ecological processes that may have consequences on wildlife pathogens. We studied the effect of co-grazing of cattle and wild elk, and of elk migratory behaviour on the occurrence of the giant liver fluke, Fascioloides magna, in elk. Migratory elk and elk herds with a higher proportion of migratory individuals were significantly less likely to be infected with F. magna. This may indicate a decreased risk of infection for migratory individuals, known as the "migratory escape" hypothesis. Elk herds overlapping with higher cattle densities also had a lower prevalence of this parasite, even after adjustment for landscape and climate variables known to influence its life cycle. Serological evidence suggests that even in low-prevalence areas, F. magna is circulating in both elk and cattle. Cattle are "dead-end" hosts for F. magna, and this may, therefore, indicate a dilution effect where cattle and elk are co-grazing. Migratory behaviour and host community composition have significant effects on the dynamics of this wildlife parasite; emphasizing the potential impacts of decisions regarding the management of migratory corridors and livestock-wildlife interface.

Better Alone or in Ill Company? The Effect of Migration and Inter-Species Comingling on Fascioloides magna Infection in Elk.

Directory of Open Access Journals (Sweden)

Mathieu Pruvot

Full Text Available Migratory movements and alteration of host communities through livestock production are examples of ecological processes that may have consequences on wildlife pathogens. We studied the effect of co-grazing of cattle and wild elk, and of elk migratory behaviour on the occurrence of the giant liver fluke, Fascioloides magna, in elk. Migratory elk and elk herds with a higher proportion of migratory individuals were significantly less likely to be infected with F. magna. This may indicate a decreased risk of infection for migratory individuals, known as the "migratory escape" hypothesis. Elk herds overlapping with higher cattle densities also had a lower prevalence of this parasite, even after adjustment for landscape and climate variables known to influence its life cycle. Serological evidence suggests that even in low-prevalence areas, F. magna is circulating in both elk and cattle. Cattle are "dead-end" hosts for F. magna, and this may, therefore, indicate a dilution effect where cattle and elk are co-grazing. Migratory behaviour and host community composition have significant effects on the dynamics of this wildlife parasite; emphasizing the potential impacts of decisions regarding the management of migratory corridors and livestock-wildlife interface.

Nano-TiO2 enhances the toxicity of copper in natural water to Daphnia magna

International Nuclear Information System (INIS)

Fan Wenhong; Cui Minming; Liu Hong; Wang Chuan; Shi Zhiwei; Tan Cheng; Yang Xiuping

2011-01-01

The acute toxicity of engineered nanoparticles (NPs) in aquatic environments at high concentrations has been well-established. This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna by increasing the copper bioaccumulation. Specifically, at 2 mg L -1 nano-TiO 2 , the (LC 50 ) of Cu 2+ concentration observed to kill half the population, decreased from 111 μg L -1 to 42 μg L -1 . Correspondingly, the level of metallothionein decreased from 135 μg g -1 wet weight to 99 μg g -1 wet weight at a Cu 2+ level of 100 μg L -1 . The copper was found to be adsorbed onto the nano-TiO 2 , and ingested and accumulated in the animals, thereby causing toxic injury. The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification by metallothioneins. - Research highlights: → This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna. → The copper was found to be adsorbed onto the nano-TiO 2 , and ingested and accumulated in the Daphnia magna, thereby causing toxic injury. → The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification mechanism of metallothionein. - The nano-TiO 2 remarkably enhanced the toxicity of copper to Daphnia magna. The nano-TiO 2 may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification mechanism of metallothionein.

Hemorrhagic onset of hemangioblastoma located in the dorsal medulla oblongata presenting with tako-tsubo cardiomyopathy and neurogenic pulmonary edema: a case report.

Science.gov (United States)

Gekka, Masayuki; Yamaguchi, Shigeru; Kazumata, Ken; Kobayashi, Hiroyuki; Motegi, Hiroaki; Terasaka, Shunsuke; Houkin, Kiyohiro

2014-01-01

Here, we present a case of dorsal medulla oblongata hemangioblastoma with fourth ventricular hemorrhage. A 23-year-old female developed sudden consciousness disturbance, and CT revealed hemorrhage in all cerebral ventricles and a hyperdense mass in the cisterna magna. Although the reddish tumor located in the dorsal medulla oblongata was successfully removed, she suffered from severe tako-tsubo cardiomyopathy (TTC) and neurogenic pulmonary edema (NPE) because of baroreflex failure and damage to the solitary tract nuclei. After intensive care for 12 weeks following surgery, she was discharged without any neurological or radiological deficits. Pathogenesis of TTC/NPE is discussed in this paper.

Selective localization of IgG from cerebrospinal fluid to brain parenchyma

DEFF Research Database (Denmark)

Mørch, Marlene Thorsen; Forsberg Sørensen, Sofie; Khorooshi, Reza M. H.

2018-01-01

the cerebrospinal fluid and induce subpial and periventricular NMO-like lesions and blood-brain barrier breakdown, in a complement-dependent manner. To investigate how IgG trafficking from cerebrospinal fluid to brain parenchyma can be influenced by injury. IgG from healthy donors was intrathecally injected...... into the cerebrospinal fluid via cisterna magna at 1, 2, 4, or 7 days after a distal stereotactic sterile needle insertion to the striatum. Antibody deposition, detected by staining for human IgG, peaked 1 day after the intrathecal injection and was selectively seen close to the needle insertion. When NMO...

Astrocyte mega-domain hypothesis of the autistic savantism.

Science.gov (United States)

Mitterauer, Bernhard J

2013-01-01

Individuals with autism who show high abilities are called savants. Whereas in their brains a disconnection in and between neural networks has been identified, savantism is yet poorly understood. Focusing on astrocyte domain organization, it is hypothesized that local astrocyte mega-organizations may be responsible for exerting high capabilities in brains of autistic savants. Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Formally, each astrocyte contacting n-neurons with m-synapses via its processes generates dynamic domains of synaptic interactions based on qualitative computation criteria, and hereby it structures neuronal information processing. If the number of processes is genetically significantly increased, these astrocytes operate in a mega-domain with a higher complexitiy of computation. From this model savant abilities are deduced. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bridge Approach Remedies Implemented at Western Mega Site

Science.gov (United States)

2017-09-01

As part of the heavy axle load (HAL) revenue service mega site testing program, the Transportation Technology Center, Inc. (TTCI) has worked closely with the Union Pacific Railroad (UP) to address bridge approach problems under HAL operations. The te...

Food mediated life history strategies in Daphnia magna : their relevance to ecotoxicological evaluations

NARCIS (Netherlands)

Enserink, E.L.

1995-01-01

The waterflea Daphnia magna is a widely used test organism in ecotoxicological studies. Acute and chronic laboratory tests yield basic information for the development of water quality standards, assessment of potential hazards of (new) chemicals, waste water licences and

Disruptive Innovation Patterns Driven by Mega-Projects: A Sustainable Development Pattern Case of China’s High-Speed Rail

Directory of Open Access Journals (Sweden)

Bingxiu Gui

2018-04-01

Full Text Available Sustainable development of mega-projects has drawn many concerns around the world. The theory of disruptive innovation in mega-projects is a typical sustainable development pattern but still lacks systematic understanding. This article takes China’s high-speed rail (CHSR project as an example to analyze the disruptive innovation pattern of mega-projects. First, this paper systematically traces the theories of disruptive innovation and summarizes the connotations of disruptive innovation. Simultaneously, from the historical development of several typical mega-projects in China, this paper summarizes the connotations of mega-projects. Based on two connotations, this paper summarizes the theoretical basis of disruptive innovation in mega-projects. Second, this paper takes the CHSR project as a case to analyze its innovation pattern from the analysis of the development process, operation mechanism and influence in sustainability; the disruptive innovation pattern is put forward afterward. Third, the discussion is drawn from the perspectives of the characteristics, scope of application and innovation environment of the disruptive innovation of CHSR. Last, the conclusions of this article are summarized.

The Mega-MUSCLES HST Treasury Survey

Science.gov (United States)

Froning, Cynthia S.; France, Kevin; Loyd, R. O. Parke; Youngblood, Allison; Brown, Alexander; Schneider, Christian; Berta-Thompson, Zachory; Kowalski, Adam

2018-01-01

JWST will be able to observe the atmospheres of rocky planets transiting nearby M dwarfs. A few such planets are already known (around GJ1132, Proxima Cen, and Trappist-1) and TESS is predicted to find many more, including ~14 habitable zone planets. To interpret observations of these exoplanets' atmospheres, we must understand the high-energy SED of their host stars: X-ray/EUV irradiation can erode a planet's gaseous envelope and FUV/NUV-driven photochemistry shapes an atmosphere's molecular abundances, including potential biomarkers like O2, O3, and CH4. Our MUSCLES Treasury Survey (Cycles 19+22) used Hubble/COS+STIS UV observations with contemporaneous X-ray and ground-based data to construct complete SEDs for 11 low-mass exoplanet hosts. MUSCLES is the most widely used database for early-M and K dwarf (>0.3 M_sun) irradiance spectra and has supported a wide range of atmospheric stability and biomarker modeling work. However, TESS will find most of its habitable planets transiting stars less massive than this, and these will be the planets to characterize with JWST. Here, we introduce the Mega-MUSCLES project, an approved HST Cycle 25 Treasury program. Following on the successful MUSCLES survey, Mega-MUSCLES will expand our target list to focus on: (a) new M dwarf exoplanet hosts with varying properties; (b) reference M dwarfs below 0.3 solar masses that may be used as proxies for M dwarf planet hosts discovered after HST's lifetime; and (c) more rapidly rotating stars of GJ1132's mass to probe XUV evolution over gigayear timescales. We will also gather the first panchromatic SEDs of rocky planet hosts GJ1132 and Trappist-1. Here, we present an overview of the Mega-MUSCLES motivation, targets list, and status of the survey and show how it extends proven methods to a key new sample of stars, upon which critically depends the long-term goal of studying habitable planet atmospheres with JWST and beyond.

Lethal/sublethal responses of Daphnia magna to acute norfloxacin contamination and changes in phytoplankton-zooplankton interactions induced by this antibiotic

Science.gov (United States)

Pan, Ying; Yan, Shi-Wei; Li, Ruo-Zhu; Hu, Yi-Wen; Chang, Xue-Xiu

2017-01-01

Although the well-known antibiotic norfloxacin (NOR) is recognized as an important environmental pollutant, little is known about its impacts on ecological processes, particularly on species interactions. In this paper, we quantified Daphnia magna (Crustacea, Cladocera) responses in mortality rate at lethal NOR concentrations (0, 25, 50, 100, 200, 300 and 400 mg L-1), and in heartbeat rate, swimming behavior and feeding rate (on the green alga Chlorella pyrenoidosa) at sublethal NOR concentrations (0, 25, 50 and 100 mg L-1) to determine the effects of this antibiotic in plankton systems. In 96-h-long lethal experiment, mortality rates of D. magna increased significantly with increasing NOR concentration and exposure time. In sublethal experiments, heartbeat rate decreased, while time ratio of vertical to horizontal swimming (TVH) and the duration of quiescence increased in D. magna individuals exposed to increasing NOR concentrations after 4 and 12 h of exposure. These collectively led to decreases in both average swimming ability and feeding rate, consistent with the positive relationship between average swimming ability and feeding rate. Overall, results indicate that, by affecting zooplankton heartbeat rate and behavior, NOR decreased feeding efficiency of D. magna even at low doses, therefore, it might seriously compromise ecosystem health and function.

Photon detector for MEGA

International Nuclear Information System (INIS)

Gagliardi, C.A.; Tribble, R.E.

1991-01-01

During the past year, we have continued work on the photon detector for the MEGA experiment at Los Alamos, a search for the rare decay μ → eγ to a sensitivity of a few parts in 10 13 . The MEGA photon detector is designed to observe the 52.38 MeV photon produced in a μ → eγ decay with an energy resolution of 1.25 MeV, a position resolution of 2 x 5 mm 2 , a directional resolution of 10 degrees, a time resolution of 500 ps, and an efficiency of 7%. It will consists of four independent concentric cylindrical pair spectrometers mounted within a 1.5 T magnetic field produced by a superconducting solenoid magnet. Each pair spectrometer includes two thin Pb foils to convert photons into e + e - pairs, and thereby, determine both their locations and their vector momenta. The inner drift chamber layer includes a delay line cathode to determine the z coordinates needed for track reconstruction. An MWPC located between two Pb layers identifies the conversion layer so that energy loss corrections may be applied, while plastic scintillators provide timing information. Our, group together with a group from the University of Houston, is responsible for the design and construction of the photon detector, as well as developing the computer codes necessary for Monte Carlo simulations and data analysis. During the past year, our efforts have focused primarily on two tasks, delay line cathode read-out and software development. This report describes our recent work on delay lines and data analysis along with a discussion of the new plans for multiplexing in the photon arm

Clinical features and long term outcome of epilepsy in periventricular nodular heterotopia. Simple compared with plus forms

Science.gov (United States)

d'Orsi, G; Tinuper, P; Bisulli, F; Zaniboni, A; Bernardi, B; Rubboli, G; Riva, R; Michelucci, R; Volpi, L; Tassinari, C; Baruzzi, A

2004-01-01

Objectives: Little is known about the long term outcome of patients with periventricular nodular heterotopia (PNH) and epilepsy, particularly the course of seizures. This study investigated the electroclinical and prognostic features of 16 patients with PNH. Methods: Of 120 patients with epilepsy and malformations of cortical development, 16 had PNH. Of these, eight patients had periventricular nodules only (simple PNH) and eight also presented with other cortical or cerebral malformations (subcortical heterotopia; polymicrogyria; focal dysplasia; schizencephaly; cortical infolding; agenesis of the corpus callosum; mega cisterna magna and cerebellar atrophy) (PNH plus). All patients underwent clinical, neurophysiological, and MRI investigation. The mean follow up was 17.3 years (2–40 years). Results: Two electroclinical patterns emerged: (1) The first pattern, associated with simple PNH, was characterised by normal intelligence and seizures, usually partial, which began during the second decade of life. The seizures never became frequent and tended to disappear or become very rare. The EEG showed focal abnormalities. (2) The second pattern, associated with PNH plus, was characterised by mental retardation and seizures that began during the first decade of life. The seizures were very frequent in most cases and sudden drops were observed in six patients. Seizures were medically refractory in four patients. The EEG showed focal and bisynchronous abnormalities. Conclusions: Two groups of PNH patients with different electroclinical and neuroradiological features can be identified after a long term follow up. The presence of other types of cortical or cerebral malformations, in addition to periventricular nodules, determines a poor prognosis. PMID:15146004

Successfully resisting a pathogen is rarely costly in Daphnia magna.

Science.gov (United States)

Labbé, Pierrick; Vale, Pedro F; Little, Tom J

2010-11-17

A central hypothesis in the evolutionary ecology of parasitism is that trade-offs exist between resistance to parasites and other fitness components such as fecundity, growth, survival, and predator avoidance, or resistance to other parasites. These trade-offs are called costs of resistance. These costs fall into two broad categories: constitutive costs of resistance, which arise from a negative genetic covariance between immunity and other fitness-related traits, and inducible costs of resistance, which are the physiological costs incurred by hosts when mounting an immune response. We sought to study inducible costs in depth using the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa. We designed specific experiments to study the costs induced by exposure to this parasite, and we re-analysed previously published data in an effort to determine the generality of such costs. However, despite the variety of genetic backgrounds of both hosts and parasites, and the different exposure protocols and environmental conditions used in these experiment, this work showed that costs of exposure can only rarely be detected in the D. magna-P. ramosa system. We discuss possible reasons for this lack of detectable costs, including scenarios where costs of resistance to parasites might not play a major role in the co-evolution of hosts and parasites.

Greek perceptions of frontier in Magna Graecia: literature and archaeology in dialogue

Directory of Open Access Journals (Sweden)

Airton POLLINI

2013-07-01

Full Text Available The paper deals with Greek perceptions of frontier in Magna Graecia, from a historical archaeological, contextual standpoint. Considering the complex relationship between literary and archaeological evidence, the paper uses as a case study the frontier in Southern Italy, discussing the subjective frontier perceptions by Greeks and Natives in interaction.

Complexidade, desenvolvimento sustentÃvel, comunicaÃÃo - o Programa um MilhÃo de Cisternas em comunidades do CearÃ

OpenAIRE

Ana ValÃria Feitosa Dias

2004-01-01

Este estudo analisa o Programa Um MilhÃo de Cisternas (P!MC), considerando os aspectos da comunicaÃÃo e da sustentabilidade nas comunidades de Livramento, MunicÃpio de IrauÃuba, e Araponga, MunicÃpio de Itapipoca. Realizou-se uma pesquisa de campo nas duas comunidades, que constou da aplicaÃÃo de entrevistas dirigidas com 31 famÃlias de Livramento e Araponga; e entrevistas semi-estruturadas com lideranÃas locais comunitÃrias e integrantes das organizaÃÃes nÃo governamentais (ON...

A comparison of the response of Simocephalus mixtus (Cladocera) and Daphnia magna to contaminated freshwater sediments.

Science.gov (United States)

Martínez-Jerónimo, Fernando; Cruz-Cisneros, Jade Lizette; García-Hernández, Leonardo

2008-09-01

The southeast region of Mexico is characterized by intensive oil industry activities carried out by the national public enterprise Petróleos Mexicanos (PEMEX). The freshwater lagoon "El Limón", located in the municipality of Macuspana, state of Tabasco, Mexico, has received over 40 years discharges of untreated waste waters from the Petrochemical Complex "Ciudad PEMEX", located on the border of the lagoon. To assess the toxicity of the sediments and, hence, to obtain information on the biological effects of these contaminating discharges, the cladoceran Simocephalus mixtus was used as a test organism in acute (48h) and chronic (12d) toxicity assays. For comparison purposes, bioassays were also conducted with the reference cladoceran Daphnia magna. The sediments of this lagoon contain important amounts of metals and hydrocarbons that have been accumulated over time; however, the acute tests only registered reduced lethal effects on the test organisms (maxima of 10% and 17% mortality for D. magna and S. mixtus, respectively). This may be due to low bioavailability of the pollutants present in the sediments. On the other hand, partial or total inhibition and delay in the start of reproduction, reduction in clutch sizes, reduced survival, as well as reduction in the size of adults and offspring were recorded in the chronic assays. The most evident chronic effects were found in S. mixtus; in this species, reproduction was inhibited up to 72%, whereas D. magna was only affected by 24%. We determined that S. mixtus is a more sensitive test organism than D. magna to assess whole-sediment toxicity in tropical environments, and that chronic exposure bioassays are required for an integrated sediment evaluation. The sediments from "El Limón" lagoon induced chronic intoxication responses and, therefore, remediation measures are urgently needed to recover environmental conditions suitable for the development of its aquatic biota.

La estrategia comunicacional en el sector mega-minero. Un estudio del caso La Alumbrera en Argentina

Directory of Open Access Journals (Sweden)

Julieta Godfrid

2016-06-01

Full Text Available En los últimos años se produjo en la Argentina una rápida expansión de la mega-minería a cielo abierto, lo que vino acompañado de un creciente aumento de la conflictividad socio-ambiental que cuestiona en profundidad las consecuencias de la actividad extractiva. En este contexto, las múltiples críticas a la mega-minería deslegitimaron profundamente la imagen del sector y de las empresas que llevan adelante este tipo de actividad. A partir de allí, las corporaciones mega-mineras se vieron frente a la necesidad de construir una nueva estrategia comunicacional integral que les permitiera mejorar su imagen y construir consenso en torno a la actividad. El presente trabajo indaga en torno a las nuevas estrategias comunicacionales del sector mega-minero que se llevan a cabo bajo el paradigma de la Responsabilidad Social Empresaria y el “marketing experiencial”. Para ello se trabaja a partir del estudio de caso del emprendimiento mega-minero más antiguo del país, la empresa La Alumbrera (Provincia de Catamarca.

Start-Up Mega Planning--A Case History

Science.gov (United States)

Forbes, Ronald; Forbes, Dylan; Hoskins, Peter

2005-01-01

Social Responsibility is becoming a key issue for organizations today. They talk about it and they make social contributions, but how do we know if anything is being achieved? A framework is required and has existed at least since 1992. Roger Kaufman's Mega Planning has slowly gathered momentum in organizations worldwide. For a faster take-up we…

Local meanings of a sport mega-event's legacies : Stories from a South African urban neighbourhood

NARCIS (Netherlands)

Waardenburg, Maikel; van den Bergh, Marjolein; van Eekeren, Frank

2015-01-01

Studies on sport mega-events and their legacies often seem only loosely connected to local experiences. Stories on sport mega-event legacy appear as a setting-the-scene or function as a reference to illustrate specific types of legacy. However, stories themselves are never the primary focus in these

Phototoxicity and oxidative stress responses in Daphnia magna under exposure to sulfathiazole and environmental level ultraviolet B irradiation

Energy Technology Data Exchange (ETDEWEB)

Kim, Jungkon [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: koguma@snu.ac.kr; Park, Yena [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: elohim@snu.ac.kr; Choi, Kyungho [School of Public Health, Seoul National University, Seoul, 110-799 (Korea, Republic of)], E-mail: kyungho@snu.ac.kr

2009-01-18

Sulfonamide antibiotics frequently occur in aquatic environments. In this study, phototoxicity of sulfathiazole (STZ) and its mechanism of action were investigated using Daphnia magna. We evaluated the changes of molecular level stress responses by assessing gene expression, enzyme induction and lipid peroxidation, and the related organism-level effects in D. magna. In the presence of ultraviolet B (UV-B) light (continuous irradiation with 13.8 {+-} 1.0 {mu}W cm{sup -2} d{sup -1}), STZ (at the nominal concentration of 94.9 mg/L) caused a significant increase in reactive oxygen species (ROS) generation and lipid peroxidation. Catalase (CAT) and glutathione S-transferase (GST) showed concentration-dependent increases caused by the exposure. Exposure to STZ and UV-B light caused apparent up-regulation of {alpha}-esterase, hemoglobin, and vitellogenin mRNA. The survival of daphnids was significantly affected by the co-exposure to STZ and UV-B. The biochemical and molecular level observations in combination with organism-level effects suggest that the phototoxicity of STZ was mediated in part by ROS generated by oxidative stress in D. magna.

Phototoxicity and oxidative stress responses in Daphnia magna under exposure to sulfathiazole and environmental level ultraviolet B irradiation

International Nuclear Information System (INIS)

Kim, Jungkon; Park, Yena; Choi, Kyungho

2009-01-01

Sulfonamide antibiotics frequently occur in aquatic environments. In this study, phototoxicity of sulfathiazole (STZ) and its mechanism of action were investigated using Daphnia magna. We evaluated the changes of molecular level stress responses by assessing gene expression, enzyme induction and lipid peroxidation, and the related organism-level effects in D. magna. In the presence of ultraviolet B (UV-B) light (continuous irradiation with 13.8 ± 1.0 μW cm -2 d -1 ), STZ (at the nominal concentration of 94.9 mg/L) caused a significant increase in reactive oxygen species (ROS) generation and lipid peroxidation. Catalase (CAT) and glutathione S-transferase (GST) showed concentration-dependent increases caused by the exposure. Exposure to STZ and UV-B light caused apparent up-regulation of α-esterase, hemoglobin, and vitellogenin mRNA. The survival of daphnids was significantly affected by the co-exposure to STZ and UV-B. The biochemical and molecular level observations in combination with organism-level effects suggest that the phototoxicity of STZ was mediated in part by ROS generated by oxidative stress in D. magna

Effects of aqueous stable fullerene nanocrystals (nC60) on the food conversion from Daphnia magna to Danio rerio in a simplified freshwater food chain.

Science.gov (United States)

Tao, Xianji; Li, Cuilan; Zhang, Bo; He, Yiliang

2016-02-01

Understanding the nanomaterial potential to the food conversion of two food chain levels is important in the ecosystem assessment as manufactured nanomaterials are being released into the environment. In this investigation, the food conversion from Daphnia magna (D. magna) (prey) to Danio rerio (D. rerio) (predator) was used as the study object of aqueous stable fullerene nanocrystals (nC60). Accumulated nC60 of D. magna was determined as the nominal initial exposure concentration for D. rerio. The results of 21-d dietary exposure experiment demonstrate that nC60 in D. magna decreased the body weight growths and condition factors of D. rerio, and reduced the food conversion ratio by 20% (from D. magna to D. rerio). Further, the experiments present that nC60 decrease three digestive enzymes activities of trypsinase, lipase, and amylase by 30, 29, and 55% in vivo, and by 60, 90, and 42% in vitro, respectively. Both in vivo and in vitro experiments indicated that nC60 was involved with the decrements of digestive enzymes activities. These decrements in digestive enzymes activities may be due to the deactivation caused by the adsorption of nC60 particles onto the surface or active center of digestive enzymes. Sum up, these results not only describe the nC60 deleterious effects on the food conversion from D. magna to D. rerio, but also provide some information regarding a probable food conversion inhibition mechanism of nC60. Copyright © 2015 Elsevier Ltd. All rights reserved.

Toxicity Identification and Evaluation for the Effluent from Wastewater Treatment Plant in Industrial Complex using D.magna

Science.gov (United States)

Lee, S.; Keum, H.; Chun Sang, H.

2015-12-01

In recent years, the interests on the impacts of industrial wastewater on aquatic ecosystem have increased with concern about ecosystem protection and human health. Whole effluent toxicity tests are used to monitor toxicity by unknown toxic chemicals as well as conventional pollutants from industrial effluent discharges. This study describes the application of TIE (toxicity identification evaluation) procedures to an acutely toxic effluent from a wastewater treatment plant in industrial complex which was toxic to Daphnia magna. In TIE phase I (characterization step), the toxic effects by heavy metals, organic compounds, oxidants, volatile organic compounds, suspended solids and ammonia were screened and revealed that the source of toxicity is far from these toxicants group. Chemical analysis (TIE phase II) on TDS showed that the concentration of chloride ion (6,900 mg/L) was substantially higher than that predicted from EC50 for D. magna. In confirmation step (TIE phase III), chloride ion was demonstrated to be main toxicant in this effluent by the spiking approach, species sensitivity approach and deletion approach. Calcium, potassium, magnesium, sodium, fluorine, sulfate ion concentration (450, 100, 80, 5,300, 0.66, 2,200mg/L) was not shown toxicity from D. magna. Finally, we concluded that chloride was the most contributing toxicant in the waste water treatment plant. Further research activities are needed for technical support of toxicity identification and evaluation on the various types of wastewater treatment plant discharge in Korea. Keywords : TIE, D. magna, Industrial waste water Acknowledgement This research was supported by a grant (15IFIP-B089908-02) from Plant Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government

Obesogens beyond Vertebrates: Lipid Perturbation by Tributyltin in the Crustacean Daphnia magna

Science.gov (United States)

Jordão, Rita; Casas, Josefina; Fabrias, Gemma; Campos, Bruno; Piña, Benjamín; Lemos, Marco F.L.; Soares, Amadeu M.V.M.; Tauler, Romà

2015-01-01

Background The analysis of obesogenic effects in invertebrates is limited by our poor knowledge of the regulatory pathways of lipid metabolism. Recent data from the crustacean Daphnia magna points to three signaling hormonal pathways related to the molting and reproductive cycles [retinoic X receptor (RXR), juvenile hormone (JH), and ecdysone] as putative targets for exogenous obesogens. Objective The present study addresses the disruptive effects of the model obesogen tributyltin (TBT) on the lipid homeostasis in Daphnia during the molting and reproductive cycle, its genetic control, and health consequences of its disruption. Methods D. magna individuals were exposed to low and high levels of TBT. Reproductive effects were assessed by Life History analysis methods. Quantitative and qualitative changes in lipid droplets during molting and the reproductive cycle were studied using Nile red staining. Lipid composition and dynamics were analyzed by ultra-performance liquid chromatography coupled to a time-of-flight mass spectrometer. Relative abundances of mRNA from different genes related to RXR, ecdysone, and JH signaling pathways were studied by qRT-PCR. Results and Conclusions TBT disrupted the dynamics of neutral lipids, impairing the transfer of triacylglycerols to eggs and hence promoting their accumulation in adult individuals. TBT’s disruptive effects translated into a lower fitness for offspring and adults. Co-regulation of gene transcripts suggests that TBT activates the ecdysone, JH, and RXR receptor signaling pathways, presumably through the already proposed interaction with RXR. These findings indicate the presence of obesogenic effects in a nonvertebrate species. Citation Jordão R, Casas J, Fabrias G, Campos B, Piña B, Lemos MF, Soares AM, Tauler R, Barata C. 2015. Obesogens beyond vertebrates: lipid perturbation by tributyltin in the crustacean Daphnia magna. Environ Health Perspect 123:813–819; http://dx.doi.org/10.1289/ehp.1409163 PMID

Urban Agglomeration and Extension in Northern Coast of West Java: A Transformation into Mega Region

Science.gov (United States)

Octifanny, Y.; Hudalah, D.

2017-07-01

In the past decade, at least three neighbouring metropolitan areas in the northwestern part of the island have been merging with each other: Jakarta Metropolitan Area (Jabodetabek), Bandung Metropolitan Area (Bandung Raya), and Cirebon Metropolitan Area (Ciayumajakuning). It is expected to be the first island-based mega-conurbation. This paper explores the potential emergence of mega region as a ground study, where mega region can be used for economic, logistic, transportation development. Authors use scoring analysis from economic and demographic indicators. The outcomes found a new and larger formation of city-region in the northern coast road networks (Pantura) - specifically western part of Java Island.

Size Matters: The Contribution of Mega-Infauna to the Food ...

Science.gov (United States)

Large-bodied, invertebrates are common to infaunal communities of NE Pacific estuaries (e.g., bivalves, polychaetes, burrowing shrimps), but their contribution to the ecological structure, function and ecosystem services of most estuaries has been poorly characterized because they are difficult to sample and quantify. In a study of Yaquina estuary (Oregon) food webs, particular effort was made to quantify intertidal and subtidal mega-infauna using suction-excavated 40-cm diameter corers in addition to conventional sampling of macro-infauna. Additionally, the abundance and biomass of all floral and other faunal guilds (except microbial and mammalian guilds) were directly quantified or estimated from published studies, carbon and nitrogen stable isotopes were measured for abundant species, and inverse analysis was used to generate models of carbon flow within food webs of the lower and upper reaches of Yaquina estuary. Benthic invertebrates dominated the biomass and respiration among faunal guilds in both estuarine reaches, whereas biomass and respiration of birds and fish were two orders-of-magnitude smaller. Mega-infauna, particularly intertidal burrowing shrimps and bivalves, constituted most of the benthic invertebrate biomass, respiration and secondary production in both reaches, although only a small fraction of the total infaunal abundance. Mega-infauna were dominant consumers of phytoplankton, major contributors of carbon to sediment organic matter, a

Teacher Counter Stories to a Citizenship Education Mega Policy Narrative. Preparing for Citizenship in Chile

Science.gov (United States)

Cavieres-Fernández, Eduardo

2017-01-01

The present article focuses on the counter stories of two Chilean social studies high school teachers. Counter stories describe how teachers use their professional experience to confront those mega narratives composed of dominant educational policies that impinge upon their pedagogical practices. The mega narrative described in this study as a…

Development of sewage system for mega-city Karachi

International Nuclear Information System (INIS)

Talat, B.; Ahsan-Ullah

2005-01-01

The growth of mega-cities in recent times has brought to the fore a large number of issues with respect environmental conditions such as development of slum areas, poor localities, solid waste disposal, management of sewage system, lack of open spaces and health facilities. One of the major issues effecting environment proper disposal of sewage and development of sewage system including recycling of sewage water and its use. The heavy pressure of population calls for adequate provision of sewage disposal in the new areas and remodeling of systems in the old areas of the cities to ensure a pollution-free environment. Recycling of sewage and prevention of sewage discharge into natural water channels and the sea has to be undertaken on urgent bases. The paper seeks to outline the present status of sewage system of the city of Karachi, the problems involved and the proposals for management and development of the system compatible with the need and requirement of mega-city population. (author)

Comparative ovarian microarray analysis of juvenile hormone-responsive genes in water flea Daphnia magna: potential targets for toxicity.

Science.gov (United States)

Toyota, Kenji; Williams, Timothy D; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

2017-03-01

The freshwater zooplankton Daphnia magna has been extensively employed in chemical toxicity tests such as OECD Test Guidelines 202 and 211. Previously, it has been demonstrated that the treatment of juvenile hormones (JHs) or their analogues to female daphnids can induce male offspring production. Based on this finding, a rapid screening method for detection of chemicals with JH-activity was recently developed using adult D. magna. This screening system determines whether a chemical has JH-activity by investigating the male offspring inducibility. Although this is an efficient high-throughput short-term screening system, much remains to be discovered about JH-responsive pathways in the ovary, and whether different JH-activators act via the same mechanism. JH-responsive genes in the ovary including developing oocytes are still largely undescribed. Here, we conducted comparative microarray analyses using ovaries from Daphnia magna treated with fenoxycarb (Fx; artificial JH agonist) or methyl farnesoate (MF; a putative innate JH in daphnids) to elucidate responses to JH agonists in the ovary, including developing oocytes, at a JH-sensitive period for male sex determination. We demonstrate that induction of hemoglobin genes is a well-conserved response to JH even in the ovary, and a potential adverse effect of JH agonist is suppression of vitellogenin gene expression, that might cause reduction of offspring number. This is the first report demonstrating different transcriptomics profiles from MF and an artificial JH agonist in D. magna ovary, improving understanding the tissue-specific mode-of-action of JH. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods

Science.gov (United States)

Tamura, Koichiro; Peterson, Daniel; Peterson, Nicholas; Stecher, Glen; Nei, Masatoshi; Kumar, Sudhir

2011-01-01

Comparative analysis of molecular sequence data is essential for reconstructing the evolutionary histories of species and inferring the nature and extent of selective forces shaping the evolution of genes and species. Here, we announce the release of Molecular Evolutionary Genetics Analysis version 5 (MEGA5), which is a user-friendly software for mining online databases, building sequence alignments and phylogenetic trees, and using methods of evolutionary bioinformatics in basic biology, biomedicine, and evolution. The newest addition in MEGA5 is a collection of maximum likelihood (ML) analyses for inferring evolutionary trees, selecting best-fit substitution models (nucleotide or amino acid), inferring ancestral states and sequences (along with probabilities), and estimating evolutionary rates site-by-site. In computer simulation analyses, ML tree inference algorithms in MEGA5 compared favorably with other software packages in terms of computational efficiency and the accuracy of the estimates of phylogenetic trees, substitution parameters, and rate variation among sites. The MEGA user interface has now been enhanced to be activity driven to make it easier for the use of both beginners and experienced scientists. This version of MEGA is intended for the Windows platform, and it has been configured for effective use on Mac OS X and Linux desktops. It is available free of charge from http://www.megasoftware.net. PMID:21546353

Nutritional value content, biomass production and growth performance of Daphnia magna cultured with different animal wastes resulted from probiotic bacteria fermentation

Science.gov (United States)

Endar Herawati, Vivi; Nugroho, R. A.; Pinandoyo; Hutabarat, Johannes

2017-02-01

Media culture is an important factor for the growth and quality of Daphnia magna nutrient value. This study has purpose to find the increasing of nutritional content, biomass production and growth performance of D. magna using different animal wastes fermented by probiotic bacteria. This study conducted using completely randomized experimental design with 10 treatments and 3 replicates. Those media used different animal manures such as chicken manure, goat manure and quail manure mixed by rejected bread and tofu waste fermented by probiotic bacteria then cultured for 24 days. The results showed that the media which used 50% chicken manure, 100% rejected bread and 50% tofu waste created the highest biomass production, population and nutrition content of D.magna about 2111788.9 ind/L for population; 342 grams biomass production and 68.85% protein content. The highest fatty acid profile is 6.37% of linoleic and the highest essential amino acid is 22.8% of lysine. Generally, the content of ammonia, DO, temperature, and pH during the study were in the good range of D. magna’s life. This research has conclusion that media used 50% chicken manure, 100% rejected bread and 50% tofu waste created the highest biomass production, population and nutrition content of D. magna.

[A high sensitivity search for mu gamma: The mega experiment at LAMPF

International Nuclear Information System (INIS)

1990-01-01

During the past 12 month period the Valparaiso University group has been active on LAMPF experiment 969, known as the MEGA experiment. This experiment is a search for the decay μ -> e γ, a decay which would violate lepton number conservation and which is strictly forbidden by the standard model for electroweak interactions. Previous searches for this decay mode have set limit the present day limit of 4.9 x 10 -11 . The MEGA experiment is designed to test the standard model predictions to one part in 10 +13

An update on MEGA: An experimental search for lepton number non-conservation

International Nuclear Information System (INIS)

Hungerford, E.V.

1998-01-01

Mega is an experiment to search for the decay μ→eγ. It is designed to test lepton-number conservation in muon decay by a background free measurement in this branching ratio at a sensitivity of a few x10 -13 . This paper reports particularly on the design and performance of the MEGA detector, as the lessons learned previously are important when new experiments are proposed which would increase the sensitivity of such a measurement down to a branching ratio on the order of 10 -14 . copyright 1998 American Institute of Physics

A socio-ecological adaptive approach to contaminated mega-site management: From 'control and correct' to 'coping with change'

Science.gov (United States)

Schirmer, Mario; Lyon, Ken; Armstrong, James E.; Farrell, Katharine N.

2012-01-01

Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed

Copper regulation and homeostasis of Daphnia magna and Pseudokirchneriella subcapitata: influence of acclimation

International Nuclear Information System (INIS)

Bossuyt, Bart T.A.; Janssen, Colin R.

2005-01-01

This study aimed to evaluate (1) the capacity of the green alga Pseudokirchneriella subcapitata and the waterflea Daphnia magna to regulate copper when exposed to environmentally realistic copper concentrations and (2) the influence of multi-generation acclimation to these copper concentrations on copper bioaccumulation and homeostasis. Based on bioconcentration factors, active copper regulation was observed in algae up to 5 μg Cu L -1 and in daphnids up to 35 μg Cu L -1 . Constant body copper concentrations (13 ± 4 μg Cu g DW -1 ) were observed in algae exposed to 1 through 5 μg Cu L -1 and in daphnids exposed to 1 through 12 μg Cu L -1 . At higher exposure concentrations, there was an increase in internal body copper concentration, while no increase was observed in bioconcentration factors, suggesting the presence of a storage mechanism. At copper concentrations of 100 μg Cu L -1 (P. subcapitata) and 150 μg Cu L -1 (D. magna), the significant increases observed in body copper concentrations and in bioconcentration factors may be related to a failure of this regulation mechanism. For both organisms, internal body copper concentrations lower than 13 μg Cu g DW -1 may result in copper deficiency. For P. subcapitata acclimated to 0.5 and 100 μg Cu L -1 , body copper concentrations ranged (mean ± standard deviation) between 5 ± 2 μg Cu g DW -1 and 1300 ± 197 μg Cu g DW -1 , respectively. For D. magna, this value ranged between 9 ± 2 μg Cu g DW -1 and 175 ± 17 μg Cu g DW -1 for daphnids acclimated to 0.5 and 150 μg Cu L -1 . Multi-generation acclimation to copper concentrations ≥12 μg Cu L -1 resulted in a decrease (up to 40%) in body copper concentrations for both organisms compared to the body copper concentration of the first generation. It can be concluded that there is an indication that P. subcapitata and D. magna can regulate their whole body copper concentration to maintain copper homeostasis within their optimal copper range and

Development of large area resistive electrodes for ATLAS NSW MicroMEGAS

CERN Document Server

Ochi, Atsuhiko; The ATLAS collaboration

2015-01-01

MicroMegas with resistive anode will be used for the NSW upgrade of the ATLAS experiment at LHC. The resistive electrode is one of key technology for MPGDs to prevent sparks. Large area resistive electrodes for the MM have been developed using two different technology; screen printing and carbon sputtering. Maximum size of each resistive foil is 45cm x 220cm with printed pattern of 425 micron pitch strips. Those technologies are also suitable to mass production. The prototypes of series production model have been produced successfully. We will report the development and production status and test results of the resistive MicroMegas.

Construction and performance of MEGAs low-mass, high-rate cylindrical MWPCs

Science.gov (United States)

Cooper, M. D.; Armijo, V.; Black, J. K.; Bolton, R. D.; Carius, S.; Espinoza, C.; Hart, G.; Hogan, G. E.; Gonzales, A.; Kroupa, M. A.; Mischke, R. E.; Sandoval, J.; Schilling, S.; Sena, J.; Suazo, G.; Whitehouse, D. A.; Wilkinson, C. A.; Stantz, K.; Szymanski, J. J.; Jui, C. C.; Gagliardi, C. A.; Tribble, R. E.; Tu, X.-L.; Fisk, R. J.; Koetke, D. D.; Manweiler, R. W.; Nord, P. M.; Stanislaus, S.; Piilonen, L. E.; Zhang, Y. D.

A design for extremely low mass, high-resolution multiwire proportional chambers (MWPC) was achieved by the MEGA collaboration in its experiment to search for the lepton family number violating decay μ→eγ. To extend the present branching ratio limit by over an order of magnitude, these MWPCs were operated in high particle fluxes. They showed minimal effects of aging, and evidenced spatial and energy resolutions for the orbiting positrons from muon decay which were consistent with our design parameters. The unique features of these chambers, their assembly into the MEGA positron spectrometer, and their performance during the experiment are described in this paper.

Effects of Cylindrospermopsis raciborskii and Aphanizomenon ovalisporum (cyanobacteria) ingestion on Daphnia magna midgut and associated diverticula epithelium

International Nuclear Information System (INIS)

Nogueira, Isabel C.G.; Lobo-da-Cunha, Alexandre; Vasconcelos, Vitor M.

2006-01-01

This article reports a light and electron microscopy investigation of the effects of Cylindrospermopsis raciborskii and Aphanizomenon ovalisporum ingestion on midgut and associated digestive diverticula of Daphnia magna. Additionally, survivorship and growth effects caused by feeding on cyanobacteria were assessed. Three cyanobacteria were used in the experiments: cylindrospermopsin (CYN)-producing C. raciborskii, CYN-producing A. ovalisporum and non-CYN-producing C. raciborskii. In order to discriminate between the alterations due to the low nutritional value of cyanobacteria and toxic effects, a control group was fed on the chlorophyte Ankistrodesmus falcatus and another control group was not fed. In the chlorophyte fed control, the epithelium lining the midgut and associated diverticula is mainly formed by strongly stained cells with an apical microvilli border. Nevertheless, unstained areas in which cell lyses had occurred were also observed. In the unfed control, the unstained areas became predominant due to an increment of cell lyses. All individuals fed on CYN-producing A. ovalisporum and some of those fed on non-CYN-producing C. raciborskii appear similar to the unfed control. However, some individuals fed on non-CYN-producing C. raciborskii showed similarities with the fed control. In contrast, the midgut and digestive diverticula of D. magna fed on CYN-producing C. raciborskii showed a widespread dissociation of epithelial cells, associated with severe intracellular disorganization, but cell lysis was less evident than in controls. These alterations cannot be attributed to CYN, because those effects were not induced by CYN-producing A. ovalisporum. Therefore, data suggest the production of another unidentified active metabolite by CYN-producing C. raciborskii, responsible for the disruption of cell adhesion in the epithelium of D. magna digestive tract. Data also show that the tested cyanobacteria are inadequate as food to D. magna, due to low nutritional

Negative effects of UVB-irradiated phytoplankton on life history traits and fitness of Daphnia magna

NARCIS (Netherlands)

Lange, de H.J.; Reeuwijk, van P.L.

2003-01-01

1. We tested the effect of ultraviolet-B (UVB)-irradiated phytoplankton on life history characteristics of Daphnia magna . Two phytoplankton species were used, Chlamydomonas reinhardtii and Cryptomonas pyrenoidifera . The phytoplankton species were cultured under photosynthetically active radiation

Successfully resisting a pathogen is rarely costly in Daphnia magna

Directory of Open Access Journals (Sweden)

Vale Pedro F

2010-11-01

Full Text Available Abstract Background A central hypothesis in the evolutionary ecology of parasitism is that trade-offs exist between resistance to parasites and other fitness components such as fecundity, growth, survival, and predator avoidance, or resistance to other parasites. These trade-offs are called costs of resistance. These costs fall into two broad categories: constitutive costs of resistance, which arise from a negative genetic covariance between immunity and other fitness-related traits, and inducible costs of resistance, which are the physiological costs incurred by hosts when mounting an immune response. We sought to study inducible costs in depth using the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa. Results We designed specific experiments to study the costs induced by exposure to this parasite, and we re-analysed previously published data in an effort to determine the generality of such costs. However, despite the variety of genetic backgrounds of both hosts and parasites, and the different exposure protocols and environmental conditions used in these experiment, this work showed that costs of exposure can only rarely be detected in the D. magna-P. ramosa system. Conclusions We discuss possible reasons for this lack of detectable costs, including scenarios where costs of resistance to parasites might not play a major role in the co-evolution of hosts and parasites.

Trends in vehicular emissions in China's mega cities from 1995 to 2005

International Nuclear Information System (INIS)

Wang Haikun; Fu Lixin; Zhou Yu; Du Xuan; Ge Weihua

2010-01-01

Multiyear inventories of vehicular emissions in Beijing, Shanghai and Guangzhou from 1995 through 2005 have been developed in this paper to study the vehicle emissions trends in China's mega cities during the past decade. The results show that the vehicular emissions of CO, HC, NO x and PM 10 have begun to slow their growth rates and perhaps even to decline in recent years due to the implementation of measures to control vehicular emissions in these cities. However, vehicular CO 2 emissions have substantially increased and still continue to grow due to little fuel economy improvement. Passenger cars and large vehicles (including heavy duty trucks and buses) are the major sources of vehicular CO 2 and CO emissions while large vehicles were responsible for nearly 70% and 80% of the vehicular NO x and PM 10 emissions in these mega cities. Motorcycles are also important contributors to vehicular emissions in Guangzhou and Shanghai. - The vehicular emissions (except CO 2 ) in China's mega cities have begun to slow their rates of growth and even to decline during the past decade.

Combining physico-chemical analysis with a Daphnia magna bioassay to evaluate a recycling technology for drinking water treatment plant waste residuals.

Science.gov (United States)

Chen, Ting; Xu, Yongpeng; Zhu, Shijun; Cui, Fuyi

2015-12-01

Recycling water treatment plant (WTP) waste residuals is considered to be a feasible method to enhance the efficiency of pollutant removal. This study also evaluated the safety and water quality of a pilot-DWTP waste residuals recycling technology by combining physical-chemistry analysis with a Daphnia magna assay. The water samples taken from each treatment step were extracted and concentrated by XAD-2 resin and were then analyzed for immobilization and enzyme activity with D. magna. The measured parameters, such as the dissolve organic carbon (DOC), UV254 and THM formation potential (THMFPs) of the recycling process, did not obviously increase over 15 days of continuous operation and were even lower than typical values from a conventional process. The extract concentration ranged from 0 to 2 Leq/ml as measured on the 7th and 15th days and the immobilization of D. magna exposed to water treated by the recycling process was nearly equivalent to that of the conventional process. Both the superoxide dismutase (SOD) and the catalase (CAT) activity assay indicated that a lower dose of water extract (0.5, 1, 1.5 Leq/ml) could stimulate the enzyme activity of D. magna, whereas a higher dose (2 Leq/ml at the sampling point C3, R3, R4 ) inhibits the activity. Moreover, the SOD and CAT activity of D. magna with DOC and UV254 showed a strong concentration-effect relationship, where the concentration range of DOC and UV254 were 4.1-16.2 mg/L and 0.071-4.382 cm(-1), respectively. The results showed that there was no statistically significant difference (p>0.05) between the conventional and recycling treatment processes and the toxicity of water samples in the recycling process did not increase during the 15-day continuous recycling trial. Copyright © 2015 Elsevier Inc. All rights reserved.

Mega-minería y colonialidad. Nuevas estrategias de legitimación, viejos binomios

OpenAIRE

Julieta Godfrid

2016-01-01

The new international division of labor that takes place under neoliberal globalization relegates Latin American countries to mere commodity producers. In this scenario, in Argentina in recent years it has rapidly expanded the mega-opencast mining, producing a multiplicity of socio-environmental impacts and bringing the emergence of a lot of conflicts. Successive socio-environmental critics contributed to delegitimize the corporate image of the sector, discrediting the mega-mining activity. F...

Hemorrhagic Onset of Hemangioblastoma Located in the Dorsal Medulla Oblongata Presenting with Tako-Tsubo Cardiomyopathy and Neurogenic Pulmonary Edema: A Case Report

Directory of Open Access Journals (Sweden)

Masayuki Gekka

2014-03-01

Full Text Available Here, we present a case of dorsal medulla oblongata hemangioblastoma with fourth ventricular hemorrhage. A 23-year-old female developed sudden consciousness disturbance, and CT revealed hemorrhage in all cerebral ventricles and a hyperdense mass in the cisterna magna. Although the reddish tumor located in the dorsal medulla oblongata was successfully removed, she suffered from severe tako-tsubo cardiomyopathy (TTC and neurogenic pulmonary edema (NPE because of baroreflex failure and damage to the solitary tract nuclei. After intensive care for 12 weeks following surgery, she was discharged without any neurological or radiological deficits. Pathogenesis of TTC/NPE is discussed in this paper.

Comparison of typical mega cities in China using emergy synthesis

Science.gov (United States)

Zhang, L. X.; Chen, B.; Yang, Z. F.; Chen, G. Q.; Jiang, M. M.; Liu, G. Y.

2009-06-01

An emergy-based comparison analysis is conducted for three typical mega cities in China, i.e., Beijing, Shanghai and Guangzhou, from 1990 to 2005 in four perspectives including emergy intensity, resource structure, environmental pressure and resource use efficiency. A new index of non-renewable emergy/money ratio is established to indicate the utilization efficiency of the non-renewable resources. The results show that for the three mega urban systems, Beijing, Shanghai and Guangzhou, the total emergy inputs were 3.76E+23, 3.54E+23, 2.52E+23 sej in 2005, of which 64.88%, 91.45% and 72.28% were imported from the outsides, respectively. As to the indicators of emergy intensity involving the total emergy use, emergy density and emergy use per cap, three cities exhibited similar overall increase trends with annual fluctuations from 1990 to 2005. Shanghai achieved the highest level of economic development and non-renewable resource use efficiency, and meanwhile, lower proportion of renewable resource use and higher environmental pressure compared to those of Beijing and Guangzhou. Guangzhou has long term sustainability considering an amount of local renewable resources used, per capita emergy used, energy consumption per unit GDP and the ratio of waste to renewable emergy. It can be concluded that different emergy-based evaluation results arise from different geographical locations, resources endowments, industrial structures and urban orientations of the concerned mega cities.

Implantation of Martian Materials in the Inner Solar System by a Mega Impact on Mars

Science.gov (United States)

Hyodo, Ryuki; Genda, Hidenori

2018-04-01

Observations and meteorites indicate that the Martian materials are enigmatically distributed within the inner solar system. A mega impact on Mars creating a Martian hemispheric dichotomy and the Martian moons can potentially eject Martian materials. A recent work has shown that the mega-impact-induced debris is potentially captured as the Martian Trojans and implanted in the asteroid belt. However, the amount, distribution, and composition of the debris has not been studied. Here, using hydrodynamic simulations, we report that a large amount of debris (∼1% of Mars’ mass), including Martian crust/mantle and the impactor’s materials (∼20:80), are ejected by a dichotomy-forming impact, and distributed between ∼0.5–3.0 au. Our result indicates that unmelted Martian mantle debris (∼0.02% of Mars’ mass) can be the source of Martian Trojans, olivine-rich asteroids in the Hungarian region and the main asteroid belt, and some even hit the early Earth. The evidence of a mega impact on Mars would be recorded as a spike of 40Ar–39Ar ages in meteorites. A mega impact can naturally implant Martian mantle materials within the inner solar system.

A genetic epidemiological mega analysis of smoking initiation in adolescents

NARCIS (Netherlands)

Maes, H.H.; Prom-Wormley, E.; Eaves, L.J.; Rhee, S.H.; Hewitt, J.K.; Young, S.; Corley, R.; McGue, M.K.; Iacono, W.G.; Legrand, L.; Samek, D.; Murrelle, E.L.; Silberg, J.L.; Miles, D.; Schieken, R.M.; Beunen, G.P.; Thomis, M.; Rose, R.J.; Dick, D.M.; Boomsma, D.I.; Bartels, M.; Vink, J.M.; Lichtenstein, P.; White, V.; Kaprio, J.; Neale, M.C.

2017-01-01

Introduction. Previous studies in adolescents were not adequately powered to accurately disentangle genetic and environmental influences on smoking initiation across adolescence. Methods. Mega-analysis of pooled genetically informative data on smoking initiation was performed, with structural

Is The Principle Of Magna Carta Regarding Religious Liberties Applied In Macedonia?

Directory of Open Access Journals (Sweden)

Nuhija Bekim

2015-12-01

Full Text Available Human rights were analyzed and described in many writings from older times. If we consider their fame and historical value, most important ones are: Great Charter of Freedoms (Magna Carta Libertatum of 1215, the Law on Rights (Bill of Rights of 1689, the Declaration of Independence of the United States of America (1776 and the Declaration of the Rights of Man and Citizen (1789.

Mega-rings Surrounding Timber Mountain Nested Calderas, Geophysical Anomalies: Rethinking Structure and Volcanism Near Yucca Mountain (YM), Nevada

Science.gov (United States)

Tynan, M. C.; Smith, K. D.; Savino, J. M.; Vogt, T. J.

2004-12-01

Observed regional mega-rings define a zone ˜80-100 km in diameter centered on Timber Mountain (TM). The mega-rings encompass known smaller rhyolitic nested Miocene calderas ( ˜11-15 my, structural relationships. Mega-rings consist of arcuate faulted blocks with deformation (some remain active structures) patterns showing a genetic relationship to the TM volcanic system; they appear to be spatially associated and temporally correlated with Miocene volcanism and two geophysically identified crustal/upper mantle features. A 50+ km diameter pipe-like high velocity anomaly extends from crustal depth to over 200 km beneath TM (evidence for 400km depth to NE). The pipe is located between two ˜100 km sub-parallel N/S linear trends of small-magnitude earthquake activity, one extending through the central NV Test Site, and a second located near Beatty, NV. Neither the kinematics nor relational mechanism of 100km seismically active N/S linear zones, pipe, and mega-rings are understood. Interpreted mega-rings are: 1) Similar in size to larger terrestrial volcanic complexes (e.g., Yellowstone, Indonesia's Toba system); 2) Located in the region of structural transition from the Mohave block to the south, N/S Basin and Range features to the north, Walker Lane to the NW, and the Las Vegas Valley shear zone to the SE; 3) Associated with the two seismically active zones (similar to other caldera fault-bounded sags), the mantle high velocity feature, and possibly a regional bouguer gravity anomaly; 4) Nearly coincident with area hydrologic basins and sub-basins; 5) Similar to features described from terrestrial and planetary caldera-collapse studies, and as modeled in laboratory scaled investigations (ice melt, balloon/sand). Post Mid-Miocene basalts commonly occur within or adjacent to the older rhyolitic caldera moats; other basaltic material occurs marginal to both the outer rings of the interpreted mega-ring system and high velocity pipe. The YM repository may be situated in

EFFECTIVE CONCENTRATIONS OF 6 CONTAMINANTS TO LEMMA MINOR, PIMEPHALES PROMELA, DAPHNIA MAGNA, AND CERIODAPHNIA DUBIA

Science.gov (United States)

The research presented here resulted in EC50 and LOEC values for the contaminants copper, cadmium, diazinon, atrazine, and cyanide to the species Lemna Minor, Pimephales promelas, Daphnia magna, and Ceriodaphnia dubia. Observed values were used as benchmarks for assessing the se...

Automated Extraction of Genomic DNA from Medically Important Yeast Species and Filamentous Fungi by Using the MagNA Pure LC System

OpenAIRE

Loeffler, Juergen; Schmidt, Kathrin; Hebart, Holger; Schumacher, Ulrike; Einsele, Hermann

2002-01-01

A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (105 to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sen...

Mega-impacts and mantle-melting episodes: tests of possible correlations

International Nuclear Information System (INIS)

Glikson, A.Y.

1996-01-01

The criteria for recognising the effects of impacts by large-diameter extraterrestrial projectiles (D p >>10 km) on thin, geothermally active crust must vary fundamentally from those pertaining to impacts on thick, cooler continental crust. Although the bulk of the terrestrial cratering records has been destroyed by both erosion of elevated terrains and plate subduction, or obscured by burial, a search for Precambrian mega-impacts is facilitated by the preservation of their likely secondary effects: mega-earthquake-triggered faults; ensuing diamictites, and the deposits of turbidity currents; microtektites; spherulitic condensates of vaporised asteroid and target materials; and distal tectonic and igeneous effects. Clues to the origin of thermal events are provided by peaks on isotopic-age histograms of precise U-Pb, Ar-Ar, amd Sm-Nd mineral-whole-rock ages. These peaks, spatially corroborated by detailed mapping of Precambrian terrains, support an episodic nature of at least certain major Precambrian events and some correlations with impact events. Preliminary time-series analyses of Precambrian events yield values consistent with the Phanerozoic galactic rotation period (250 ± 50 Ma), and the solar system's cross-galactic-plane oscillation period (33 ± 3 Ma). It has been demonstrated that possible correlations between mega-impacts and tectonic/thermal events are capable of being tested through isotopic-age studies of diamictites and spherule units of impact origin and of rifting and mafic igneous events. 123 refs., 2 tabs., 7 figs

Draft Genome Sequence of Serratia sp. Strain DD3, Isolated from the Guts of Daphnia magna

OpenAIRE

Poehlein, Anja; Freese, Heike M.; Daniel, Rolf; Simeonova, Diliana D.

2014-01-01

We report the draft genome sequence of Serratia sp. strain DD3, a gammaproteobacterium from the family Enterobacteriaceae. It was isolated from homogenized guts of Daphnia magna. The genome size is 5,274 Mb. peerReviewed

Growth and Survival Rate of Tilapia (Oreochromis niloticus Larvae Fed by Daphnia magna Cultured With Organic Fertilizer Resulted From Probiotic Bacteria Fermentation

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Vivi Endar Herawati

2015-10-01

Full Text Available Daphnia magna is a potential feed for fish. The aim of this research was to find the best treatment and effect of D. magna culture addition from fermented organic fertilizer, to growth and survival rate of Oreochromis niloticus larvae. There were five treatments, each with three repetitions used in the study. All treatments used chicken dung, and different combinations of rice bran, coconut oilcake waste and tilapia larvae. Feeding on tilapia was given by ad libitum method for five times a day until 14 days. Water quality during the research was maintained at temperature 28–29°C, DO 0.3 ppm and pH 8.1–8.2. Observed variables include relative growth rate, survival rate, food consumption rate and water quality. Our results showed that D. magna cultured by fermented organic fertilizer for tilapia larvae (O. niloticus had high significant effect (p < 0.01 on the relative growth rate and survival rate. Treatment of D. magna cultured by 1.2 g/L chicken manure, 0.9 g/L rice bran and 0.3 g/L coconut oilcake showed the highest value on the relative growth rate (10.86%; survival rate (98.46% and food consumption at first week (106.43% and second week (152.76%.

The protective roles of TiO2 nanoparticles against UV-B toxicity in Daphnia magna.

Science.gov (United States)

Liu, Jie; Wang, Wen-Xiong

2017-09-01

Aquatic environments are increasingly under environmental stress due to ultraviolet (UV) radiation and potential inputs of nanoparticles with intense application of nanotechnology. In this study, we investigated the interaction between UV-B radiation and titanium nanoparticles (TiO 2 -NPs) in a model freshwater cladoceran Daphnia magna. UV-B toxicity to Daphnia magna was examined when the daphnids were exposed to a range of TiO 2 -NPs concentrations with an initial 5 or 10min of 200μW/cm 2 UV-B radiation. In addition, UV-B toxicity was also examined in the presence of TiO 2 -NPs in the body of daphnids. Our results demonstrated that the daphnid mortality under UV-B radiation decreased significantly in the presence of TiO 2 -NPs both in the water and in the body, indicating that TiO 2 -NPs had some protective effects on D. magna against UV-B. Such protective effect was mainly caused by the blockage of UV-B by TiO 2 -NPs adsorption. UV-B produced reactive oxygen species (ROS) in the water and in the daphnids, which was not sufficient to cause mortality of daphnids over short periods of radiation. Previous studies focused on the effects of TiO 2 -NPs on the toxicity of total UV radiation, and did not attempt to differentiate the potential diverse roles of UV-A and UV-B. Our study indicated that TiO 2 -NPs may conversely protect the UV-B toxicity to daphnids. Copyright © 2017 Elsevier B.V. All rights reserved.

Review of laser mega joule target area: Design and processes

International Nuclear Information System (INIS)

Geitzholz, M.; Lanternier, C.

2006-01-01

The Laser Mega Joule (LMJ) target area is currently designed to achieve ignition and significant fusion gain in laboratory. LMJ will be composed of 240 identical large 370 mm * 370 mm square laser beams. These beams will focus 2 mega-joules of energy at the wavelength of 351 nm on the center of an experiment chamber. Design studies for target equipment are well advanced, target chamber and target holder (concrete) works have already begun. A detailed overview of the target area equipment is presented: target chamber, frame, diagnostic inserter manipulator, final optic assembly, dual diagnostic and laser reference, non cryogenic target positioner. Recent technical and architectural choices are detailed including safety transfers and alignment processes (target, laser and diagnostic). All this target equipment allows us to optimize shot chrono-gram, from target metrology to the shot, including calibration process. (authors)

Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands

Energy Technology Data Exchange (ETDEWEB)

Duchet, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Caquet, Th. [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France); Franquet, E. [Universite Paul Cezanne, Institut Mediterraneen d' Ecologie et de Paleoecologie, Faculte des Sciences et Techniques Saint Jerome, C31, Marseille F-13397 (France); Lagneau, C. [Entente Interdepartementale de Demoustication du Littoral Mediterraneen, 165 avenue Paul-Rimbaud, Montpellier F-34184 (France); Lagadic, L., E-mail: Laurent.Lagadic@rennes.inra.f [INRA, UMR985 Ecologie et Sante des Ecosystemes, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint Brieuc, Rennes F-35042 (France)

2010-05-15

The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 mug L{sup -1}) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 muL L{sup -1}) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors. - Significant interaction between salinity and spinosad exposure impairs the recovery of a natural population of Daphnia magna.

“Corte Transversal”: una mega escultura entre el río Mapocho y la autopista Costanera Norte en Santiago de Chile/ “Corte Transversal”: a mega sculpture between the Mapocho River and the Costanera Norte toll road in Santiago de Chile

Directory of Open Access Journals (Sweden)

Revista de Urbanismo, Departamento de Urbanismo de la Facultad de Arquitectura y Urbanismo de la Universidad de Chile. (Reportaje de M.I.PavezR.- M.P.Henríquez.O

2008-12-01

Full Text Available “Corte Transversal”: una mega escultura entre el río Mapocho y la autopista Costanera Norte en Santiago de Chile/“Corte Transversal”: a mega sculpture between the Mapocho River and the Costanera Norte toll road in Santiago de Chile

Relationship between trans-generational effects of tetracycline on Daphnia magna at the physiological and whole organism level

International Nuclear Information System (INIS)

Kim, Hyun Young; Yu, Seungho; Jeong, Tae-yong; Kim, Sang Don

2014-01-01

The effects of pharmaceuticals have been underestimated during single generation exposure. Therefore, in this study, we investigated toxic responses at the physiological and whole organism level in tetracycline-exposed Daphnia magna over four consecutive generational lifecycles. The results showed that tetracycline affected energy-related physiological functions in concentration- and generation-dependent manners, and especially maintenance costs increased. Consequently, multigenerational exposure to tetracycline induced changes in energy balance, resulting in the change of higher levels of biological responses. In contrast, D. magna acclimated to tetracycline exposure over multiple generations, as evidenced by the increased LC 50 values. Transgenerational adaptation was related to the neonatal sensitivity and energy reserves of the organism. The results also emphasized the idea that the number of generation is an important factor for toxicity. The present study confirmed that toxic stress induces metabolic changes in an organism, thereby leading to increased energy consumption that results in adverse effects on reproduction. - Highlights: • Transgenerational adaptation of D. magna to tetracycline was observed. • TCN affected energy-related physiological function and increased maintenance energy. • LC 50 value of TCN increased with increasing concentration and generation. • The number of exposure generation may be an important factor for toxicity. - The change in internal energy balance in daphnids during multigenerational exposure to tetracycline may explain whole organism responses

Pharmacological and morphological characteristics of the muscular system of the giant liver fluke (Fascioloides magna - Bassi 1875).

Science.gov (United States)

Trailović, Saša M; Marinković, Darko; Trailović, Jelena Nedeljković; Milovanović, Mirjana; Marjanović, Djordje S; Aničić, Milan R

2015-12-01

Motility is required for feeding, reproduction and maintenance of the fluke in the host's liver. According to that, the neuromuscular system can be an attractive drugable target for chemotherapy. Musculature of the Fascioloides magna is organized into three layers, an outer circular layer, beneath this layer the longitudinal layer, and third, the oblique, or diagonal layer underlies the longitudinal layer. In our study, the administration of atropine or caffeine did not cause classic muscle contractions of F. magna muscle strips. However, the Electrical Field Stimulation (EFS) induced stable and repeatable contractions, which enabled us to examine their sensitivity to the various substances. Acetylcholine (ACh) (300 μM and 1 mM), caused only a slight relaxation, without affecting the amplitude of spontaneous contractions or the amplitude of contractions induced by EFS. Contrary to that, atropine (100 μM) caused a significant increase in the basal tone and an increase of EFS-induced contractions. If acetylcholine is an inhibitory neurotransmitter in trematodes, the described effects of atropine are achieved by the blockade of inhibitory neurotransmission. On the other hand, with respect to the process of excitation-contraction coupling, the plant alkaloid ryanodine (30 μM) significantly reduced the basal tone, as well as EFS-induced contractions of F. magna muscle strips. Ryanodine inhibited the potentiating effect of atropine on the basal tone and contractions caused by EFS, which indicates that the contractile effect of atropine is dependent on Ca(++) release from intracellular stores. Caffeine (500 μM) caused relaxation of fluke muscle strips and at the same time significantly enhanced the EFS-induced contractions. Both effects of caffeine can be explained by entry of extracellular Ca(++) into muscle cells. The muscle contractility of F. magna depends both on the entry of extracellular calcium, and calcium release from intracellular stores, which are

Evaluation of electrophoretic profile and albumin quota in the cerebrospinal fluid of dogs with distemper showing or not neurvous signs Avaliação do perfil eletroforético e da cota de albumina do líquido cerebrospinal de cães acometidos pela cinomose apresentando ou não sinais neurológicos

Directory of Open Access Journals (Sweden)

F.G.V. Gama

2007-02-01

Full Text Available The electrophoretic profile of cerebrospinal fluid proteins and albumin quota was studied in healthy dogs and dogs with distemper in either nervous or non-nervous phases. Cerebrospinal fluid (CSF samples from 30 dogs were collected by puncture of the cisterna magna. The total protein content, the albumin quota, and the electrophoretic fraction of CSF proteins in agarose gel plates were evaluated. Results were similar in healthy dogs and dogs with distemper and no nervous signs, but were significantly increased in the group of dogs with distemper showing nervous signs. The study of CSF protein profile proved useful and contributed significantly on the detection of central nervous system disorders and damages to the blood-brain barrier during the nervous phase of distemper.Estudaram-se o perfil eletroforético das proteínas liquóricas e a cota de albumina em cães sem e com cinomose na fase neurológica e não-neurológica. A punção da cisterna magna para a obtenção de amostras de liquor realizou-se em 30 cães. Analisaram-se teores de proteínas totais, cota de albumina e fracionamento eletroforético das proteínas liquóricas em gel de agarose. Os resultados foram semelhantes nos cães normais e nos cães com cinomose sem sinais neurológicos e significativamente elevados no grupo de cães com cinomose apresentando sinais neurológicos. O estudo do quadro protéico do líquido cérebroespinhal foi útil e contribuiu significativamente na detecção de lesões ao sistema nervoso central e de danos à barreira hematoencefálica durante a fase neurológica da cinomose.

Effects of various metals on survival, growth, reproduction, and metabolism of Daphnia magna

Energy Technology Data Exchange (ETDEWEB)

Biesinger, K E; Christensen, G M

1972-01-01

The toxicities of various metals to Daphnia magna were evaluated on the basis of a 48-hr 50% lethal concentration (lc50) 3-week 16% reproductive impairment concentrations (In micrograms per liter) for the metal ions tested were: Na(I), 680,000; Ca(II), 116,000; Mg(II), 82,000; K(I), 53,000; Sr(II), 42,000; Ba(II), 5,800; Fe(III), 4,380; Mn(II), 4,100; As(V), 520; Sn(II), 350; Cr(III), 330; Al(III), 320; Zn(II), 70; Au(III), 60; Ni(II), 30; Pb(II), 30; Cu(II), 22; Pt(IV), 14; Co(II), 10; Hg(II), 3.4; and Cd(II), 0.17. At mental concentrations permitting survival but impairing reproduction, daphnids weighed less than control animals. Amounts of total protein and glutamic oxalacetic transaminase activity varied with the different metals. The negative logarithm of the solubility product constant 8 pksp of the metal sulfides, electronegativity, and the logarithm of the equilibrium constant (log keg) of the metal-ATP complex were positively correlated with toxicity to D. magna. Other physicochemical properties were considered, but no additional correlations were found.

Using isotope geochemistry to discuss the role of crust-mantle interaction in the formation of endogenetic mega-deposits

International Nuclear Information System (INIS)

Zhang Lisheng

2005-01-01

Isotope characteristics of some mega-deposits from literature and new results on twenty deposits (ten of them are mega-deposits) show that there exists traces of crust-mantle interaction. It has been established that the interaction all took place in the mantle under many situations. The theory of isotope geochemistry on the genesis of mega-deposits has been discussed. According to the theory, these deposits are a kind of special phenomena, but they have a common factor, i.e. mantle metasomatism produced by the crust-mantle interaction in the mantle no matter what the ore-forming elements diversity may be. The granites with great accumulation of uncompatible elements can be considered as the analogues of mega-deposits. According to the statistical results, it is possible that they formed at a period before about 2 Ga during which the recycling of the materials was accompanied with the obvious crust-mantle interaction and can produce the volatile components which are poor in the mantle. (authors)

Study on the Effect of Heavy metals toxicity according to changing Hardness concentration using D.magna

Science.gov (United States)

Chun Sang, H.

2016-12-01

n order to determine and prevent the number of ecological effects of heavy metals in the materials, we have to accurately measure the heavy metals present in the water-based protection ecosystems and may determine the effects to humans. Heavy metals occurred in the industrial effluent which is a state in which the monitor, based on the emission standards are made by the Ministry of Environment and managed and waste water contained Copper, Zinc, lead, etc. These heavy metals are able to express the toxic effects only when present in the free-ions in the aqueous condition, which appears differently affected by the degree to hardness change in accordance with the season, precipitation. Generally changing hardness concentration can not precisely evaluate toxic effects of heavy metals in the water system. Anderson announced a study on bioassay for heavy metals from industrial waste water using Daphnia magna(Anderson, 1944, 1948). Breukelman published study the resitivity difference for the mercury Chloride(HgCl2). Braudouin(1974) compared the zooplankton(Daphnia sp.) acute toxicity of the different heavy metals and confirmed the sensitivity. Shcherban(1979) presented for toxicity evaluation results for the heavy metal of the Daphnia magna according to different temperature conditions. In the United States Environmental Protection Agency(EPA) established a standard test method for water fleas, managed and supervised water ecosystems, and announced the adoption of a bioassay standard method. This study was performed to evaluate acute inhibition using the Daphnia magna for the biological effect of heavy metal ions in water-based toxicity in the hardness change. Evaluation methods were conducted in EPA Water Quality process test criteria. TU(Toxic Unit), NOEC (No Observable Effect Concentration), LOEC (Lowest Observable Effect Concentration), EC50 (Median Effective Concentration) was calculated by Toxcalc 5.0 Program. Keywords : D. magna, Hardness, Toxic Unit, Heavy metal

Research on Trypanosoma cruzi and Analysis of Inflammatory Infiltrate in Esophagus and Colon from Chronic Chagasic Patients with and without Mega

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Eliângela de Castro Côbo

2012-01-01

Full Text Available To compare parasitism and inflammatory process in esophagus and colon from chronic chagasic patients, immunohistochemistry was carried out to research for T. cruzi and to evaluate the inflammatory infiltrate in the muscular and myenteric plexus in 39 esophagi (20 with and 19 without megaesophagus and 50 colons (25 with and 25 without megacolon. The frequency of T. cruzi in megaesophagus was 20%, and in megacolon it was 4%. No amastigotes were found in organs without mega; considering the total of esophagi (with and without mega, the frequency of T. cruzi would be 10% and 2% in the colon. Myositis and ganglionitis were more frequent and intense in organs with mega compared to those without mega, and in esophagus compared to colon. Qualitatively, inflammatory infiltration in esophagus and colon, with or without mega, was similar, consisting predominantly of T lymphocytes (CD3+, scarce macrophages (CD68+, and rare B lymphocytes (CD20+.

Research on Trypanosoma cruzi and Analysis of Inflammatory Infiltrate in Esophagus and Colon from Chronic Chagasic Patients with and without Mega

Science.gov (United States)

Côbo, Eliângela de Castro; Silveira, Thales Parenti; Micheletti, Adilha Misson; Crema, Eduardo; Adad, Sheila Jorge

2012-01-01

To compare parasitism and inflammatory process in esophagus and colon from chronic chagasic patients, immunohistochemistry was carried out to research for T. cruzi and to evaluate the inflammatory infiltrate in the muscular and myenteric plexus in 39 esophagi (20 with and 19 without megaesophagus) and 50 colons (25 with and 25 without megacolon). The frequency of T. cruzi in megaesophagus was 20%, and in megacolon it was 4%. No amastigotes were found in organs without mega; considering the total of esophagi (with and without mega), the frequency of T. cruzi would be 10% and 2% in the colon. Myositis and ganglionitis were more frequent and intense in organs with mega compared to those without mega, and in esophagus compared to colon. Qualitatively, inflammatory infiltration in esophagus and colon, with or without mega, was similar, consisting predominantly of T lymphocytes (CD3+), scarce macrophages (CD68+), and rare B lymphocytes (CD20+). PMID:22131997

Population structure and dispersal routes of an invasive parasite, Fascioloides magna, in North America and Europe

Czech Academy of Sciences Publication Activity Database

Juhasova, L.; Kraľová-Hromadová, I.; Bazsalovicsová, E.; Minárik, G.; Štefka, Jan; Mikulíček, P.; Pálková, L.; Pybus, M.

2016-01-01

Roč. 9, OCT 13 (2016), č. článku 547. ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : microsatellites * parasite * giant liver fluke * Fascioloides magna * genetic interrelationships * migratory routes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.080, year: 2016

Exposure of Daphnia magna to trichloroethylene (TCE) and vinyl chloride (VC): evaluation of gene transcription, cellular activity, and life-history parameters.

Science.gov (United States)

Houde, Magali; Douville, Mélanie; Gagnon, Pierre; Sproull, Jim; Cloutier, François

2015-06-01

Trichloroethylene (TCE) is a ubiquitous contaminant classified as a human carcinogen. Vinyl chloride (VC) is primarily used to manufacture polyvinyl chloride and can also be a degradation product of TCE. Very few data exist on the toxicity of TCE and VC in aquatic organisms particularly at environmentally relevant concentrations. The aim of this study was to evaluate the sub-lethal effects (10 day exposure; 0.1; 1; 10 µg/L) of TCE and VC in Daphnia magna at the gene, cellular, and life-history levels. Results indicated impacts of VC on the regulation of genes related to glutathione-S-transferase (GST), juvenile hormone esterase (JHE), and the vitelline outer layer membrane protein (VMO1). On the cellular level, exposure to 0.1, 1, and 10 µg/L of VC significantly increased the activity of JHE in D. magna and TCE increased the activity of chitinase (at 1 and 10 µg/L). Results for life-history parameters indicated a possible tendency of TCE to affect the number of molts at the individual level in D. magna (p=0.051). Measurement of VG-like proteins using the alkali-labile phosphates (ALP) assay did not show differences between TCE treated organisms and controls. However, semi-quantitative measurement using gradient gel electrophoresis (213-218 kDa) indicated significant decrease in VG-like protein levels following exposure to TCE at all three concentrations. Overall, results indicate effects of TCE and VC on genes and proteins related to metabolism, reproduction, and growth in D. magna. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Why Academics Choose to Publish in a Mega-Journal

Science.gov (United States)

Shopovski, Jovan; Marolov, Dejan

2017-01-01

With their broad scope, high publishing volume, a peer review process based on the scientific soundness of the content, and an open access model, mega journals have become an important part of scholarly publishing. The main aim of this paper is to determine the most important factor that influenced researchers' decisions to submit their academic…

The effects of food availability on growth and reproduction of Daphnia magna exposed to silver nanoparticles

DEFF Research Database (Denmark)

Mackevica, Aiga; Skjolding, Lars Michael; Gergs, A.

) were performed using 30 nm citric acid stabilized AgNP. The aim of the study was, besides providing data for the chronic toxicity of AgNP, to study the influence of the food availability on the reproductive toxicity of AgNP in Daphnia magna. The exposure concentrations applied ranged from 2 to 50 μg...... to controls, whereas concentrations above 10 μgAg/L resulted in inhibition of growth and reproduction as well as an increased mortality. The addition of higher amounts of food showed a beneficial effect on animal survival, growth and reproduction. Similar as in normal food availability treatment, animals......The number of available studies on the acute effects of silver nanoparticles (AgNP) on aquatic organisms has increased dramatically in recent years, but there is still very limited information available on chronic effects. In this study, a series of Daphnia magna 21-days reproduction test (OECD 211...

Internal Occipital Crest Misalignment with Internal Occipital Protuberance: A Case Report of Posterior Cranial Fossa Anatomic Variations

Science.gov (United States)

Kim, Jae Ha

2016-01-01

During gross anatomy head and neck laboratory session, one dissection group observed an abnormal anatomic variation in the posterior cranial fossa of a 94-year-old male cadaver. The internal occipital crest was not aligned with internal occipital protuberance and groove for superior sagittal sinus. It seemed that the internal occipital protuberance was shifted significantly to the right side. As a result the skull was overly stretched in order to connect with the internal occipital ridge. These internal skull variations of occipital bone landmarks can influence the location of adjacent dural venous sinuses and possibly influence cerebrospinal fluid flow. Similar anatomical anomalies have been attributed to presence of hydrocephalus and abnormalities in cisterna magna. PMID:27648322

Multi-generation cadmium acclimation and tolerance in Daphnia magna Straus

International Nuclear Information System (INIS)

Muyssen, Brita T.A.; Janssen, Colin R.

2004-01-01

The cladoceran Daphnia magna was acclimated for seven generations to cadmium concentrations ranging from 0 (control) to 250 μg/l Cd (corresponding to a free ion activity of 4.60 nM Cd 2+ ). Acute and chronic cadmium tolerance as well as cadmium accumulation were monitored as a function of acclimation time. After two to three generations of acclimation to concentrations ranging from 0.23 to 1.11 nM Cd 2+ increases in acute tolerance were maximal (factor 7.2) and significant. Acclimation for seven generations to the same acclimation concentrations did result in an increased chronic cadmium tolerance (21 days EC 50 values increased). Organisms acclimated to 1.93 nM Cd 2+ were equally or more sensitive than non-acclimated daphnids in acute and chronic toxicity tests. Cadmium contents in D. magna increased significantly as a function of the acclimation concentration. Maximum body burdens of 236±30 μg Cd/g dry weight were measured in organisms exposed to 4.60 nM Cd 2+ , but detoxification mechanisms were only successful up to 82±20 μg Cd/g dry weight as this concentration did not cause major decreases in survival and reproduction in chronic toxicity tests. As the potential positive effect of acclimation on cadmium tolerance disappeared with successive acclimation generations and increasing acclimation concentrations, it is concluded that multi-generation acclimation studies are important for the evaluation of the long-term effects of environmental toxicants. - Multi-generation acclimation studies are important for evaluating long-term effects of aquatic pollutants

Systems Engineering in the Information Age: The Challenge of Mega-Systems

National Research Council Canada - National Science Library

Stevens, Renee

2004-01-01

.... We call these mega-systems. This paper focuses on the engineering of this class of systems which is characterized by increasing scale, the nature and pace of change of the technologies involved, the complexity of system...

The development of pathogen resistance in Daphnia magna: implications for disease spread in age-structured populations.

Science.gov (United States)

Garbutt, Jennie S; O'Donoghue, Anna J P; McTaggart, Seanna J; Wilson, Philip J; Little, Tom J

2014-11-01

Immunity in vertebrates is well established to develop with time, but the ontogeny of defence in invertebrates is markedly less studied. Yet, age-specific capacity for defence against pathogens, coupled with age structure in populations, has widespread implications for disease spread. Thus, we sought to determine the susceptibility of hosts of different ages in an experimental invertebrate host-pathogen system. In a series of experiments, we show that the ability of Daphnia magna to resist its natural bacterial pathogen Pasteuria ramosa changes with host age. Clonal differences make it difficult to draw general conclusions, but the majority of observations indicate that resistance increases early in the life of D. magna, consistent with the idea that the defence system develops with time. Immediately following this, at about the time when a daphnid would be most heavily investing in reproduction, resistance tends to decline. Because many ecological factors influence the age structure of Daphnia populations, our results highlight a broad mechanism by which ecological context can affect disease epidemiology. We also show that a previously observed protective effect of restricted maternal food persists throughout the entire juvenile period, and that the protective effect of prior treatment with a small dose of the pathogen ('priming') persists for 7 days, observations that reinforce the idea that immunity in D. magna can change over time. Together, our experiments lead us to conclude that invertebrate defence capabilities have an ontogeny that merits consideration with respect to both their immune systems and the epidemic spread of infection. © 2014. Published by The Company of Biologists Ltd.

Comportamento do peso do coração e do corpo em chagásicos crônicos com e sem "megas"

Directory of Open Access Journals (Sweden)

Hipólito de Oliveira Almeida

1980-12-01

Full Text Available O peso do coração é menor nos chagásicos com "megas" do que nos falecidos subitamente ou em I.C.C., sendo, porém, maior que nos controles. Já o peso corporal ésemelhante nos chagásicos falecidos subitamente e nos controles, havendo redução moderada no grupo com I.C.C., e rtiais acentuada nos chagásicos com "megas" (redução de 20% em relação aos controles. A relação percentual peso cardíaco/peso corporal é de 1,1% no grupo com I.C.C.; 0,71% no grupo de morte súbita; 0,77% no grupo com "megas"; 0,49% no grupo controle e 0,60% ne grupo de doenças caquetizantes. Com base nas médias dos pesos cardíacos e corporal dos grupos controle, de doenças caquetizantes e de megas, calculou-se que o emagrecimento ocorrido nos megas reduziria o peso cardíaco médio de apenas 6,8%.Heart weight is less in chagasic patients with "mega" syndromes than in those which have died suddenly or with congestive heart failure, it is, however, greater than in the Controls. Body weight is similar in chagasic patients who have died suddenly and in the Controls, there is a moderate body weight reduction in the group with congestive heart failure, and a more accentuated reduction in chagasic patients with "mega" syndromes (a reduction of 20% in comparíson with the Controls. The relationship between heart - weight and body - weight, expressed as a percentage is 1,1% in the group with congestive heart failure; 0,71% in the group which died suddenly; 0.77% in the group with "mega" syndromes, 0.49% in the Controls group and 0.60% in the group with cachexia producing diseases. On the basis of mean heart - weights and body - weights of the control group, group with cachexia producing diseases and group with "mega" syndromes it was calculated that the emaciation which occurred in those with "mega"syndromes could reduce mean heart - weight by at least 6.8%.

Acute and chronic toxicity of four frequently used UV filter substances for Desmodesmus subspicatus and Daphnia magna.

Science.gov (United States)

Sieratowicz, Agnes; Kaiser, Dominic; Behr, Maximilian; Oetken, Matthias; Oehlmann, Jörg

2011-01-01

As a consequence of growing public concern about UV radiation effects on human health chemical and physical UV filters are increasingly used in personal care and other products. The release of these lipophilic and often persistent compounds into surface waters may pose a risk for aquatic organisms. The aim of the study was to determine effects of four frequently used UV filters on primary aquatic producers and consumers, the green alga Desmodesmus subspicatus and the crustacean Daphnia magna. Exposure to benzophenone 3 (BP3), ethylhexyl methoxycinnamate (EHMC), 3-benzylidene camphor (3-BC) and 3-(4'-methylbenzylidene)-camphor (4-MBC) resulted in growth inhibition of D. subspicatus with 72 h IC(10) values of 0.56 mg/L (BP 3), 0.24 mg/L (EHMC), 0.27 mg/L (3-BC) and 0.21 mg/L (4-MBC). EC(50) concentrations in the acute test with D. magna were 1.67, 0.57, 3.61 and 0.80 mg/L for BP3, EHMC, 3-BC and 4-MBC, respectively. Chronic exposure of D. magna resulted in NOECs of 0.04 mg/L (EHMC) and 0.1 mg/L (3-BC and 4-MBC). BP 3 showed no effects on neonate production or the length of adults. Rapid dissipation of these substances from the water phase was observed indicating the need for more frequent test medium renewal in chronic tests or the use of flow-through test systems.

Spectral SAR Ecotoxicology of Ionic Liquids: The Daphnia magna Case

International Nuclear Information System (INIS)

Putz, M.V.; Lacrama, A.M.; Ostafe, V.; Lacrama, A.M.

2007-01-01

Aiming to provide a unified theory of ionic liquids eco toxicity, the recent spectral structure activity relationship (S-SAR) algorithm is employed for testing the two additive models of anionic-cationic interaction containing ionic liquid activity: the causal and the endpoint, |0+> and |1+> models, respectively. As a working system, the Daphnia magna eco toxicity was characterized through the formulated and applied spectral chemical-eco biological interaction principles. Specific anionic-cationic-ionic-liquid rules of interaction along the developed mechanistic hypersurface map of the main eco toxicity paths together with the so-called resonance limitation of the standard statistical correlation analysis were revealed.

(O)Mega split

Energy Technology Data Exchange (ETDEWEB)

Benakli, Karim; Darmé, Luc; Goodsell, Mark D. [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589,LPTHE, F-75005, Paris (France); CNRS, UMR 7589,LPTHE, F-75005, Paris (France)

2015-11-16

We study two realisations of the Fake Split Supersymmetry Model (FSSM), the simplest model that can easily reproduce the experimental value of the Higgs mass for an arbitrarily high supersymmetry scale M{sub S}, as a consequence of swapping higgsinos for equivalent states, fake higgsinos, with suppressed Yukawa couplings. If the LSP is identified as the main Dark matter component, then a standard thermal history of the Universe implies upper bounds on M{sub S}, which we derive. On the other hand, we show that renormalisation group running of soft masses aboveM{sub S} barely constrains the model — in stark contrast to Split Supersymmetry — and hence we can have a “Mega Split” spectrum even with all of these assumptions and constraints, which include the requirements of a correct relic abundance, a gluino life-time compatible with Big Bang Nucleosynthesis and absence of signals in present direct detection experiments of inelastic dark matter. In an appendix we describe a related scenario, Fake Split Extended Supersymmetry, which enjoys similar properties.

The positively phototactic reaction of daphnia magna straus: A contribution to the understanding of diurnal vertical migration

NARCIS (Netherlands)

Ringelberg, J.

1964-01-01

The present investigation was aimed at gaining more insight into the physiological mechanism underlying the diurnal vertical migration of planktonic animals. The experiments were carried out on Daphnia magna. Only reactions to decreases in light intensity were studied. Kinetical

Protein-accumulating cells and dilated cisternae of the endoplasmic reticulum in three glucosinolate-containing genera: Armoracia, Capparis, Drypetes.

Science.gov (United States)

Jørgensen, L B; Behnke, H D; Mabry, T J

1977-01-01

Three glucosinolate-containing species, Armoracia rusticana Gaertner, Meyer et Scherbius (Brassicaceae), Capparis cynophallophora L. (Capparaceae) and Drypetes roxburghii (Wall.) Hurusawa (Euphorbiaceae), are shown by both light and electron microscopy to contain protein-accumulating cells (PAC). The PAC of Armoracia and Copparis (former "myrosin cells") occur as idioblasts. The PAC of Drypetes are usual members among axial phloem parenchyma cells rather than idioblasts. In Drypetes the vacuoles of the PAC are shown ultrastructurally to contain finely fibrillar material and to originate from local dilatations of the endoplasmic reticulum. The vacuoles in PAC of Armoracia and Capparis seem to originate in the same way; but ultrastructurally, their content is finely granular. In addition, Armoracia and Capparis are shown by both light and electron microscopy to contain dilated cisternae (DC) of the endoplasmic reticulum in normal parenchyma cells, in accord with previous findings for several species within Brassicaceae. The relationship of PAC and DC to glucosinolates and the enzyme myrosinase is discussed.

Ecotoxicological assessment of Roundup-ready soybean agriculture investigated in a D. magna model

OpenAIRE

Cuhra, Marek

2015-01-01

Paper III of this thesis is not available i Munin: III: M. Cuhra, T. Traavik & T. Bøhn. 2014. 'Life cycle fitness differences in Daphnia magna fed Roundup-Ready soybean or conventional soybean or organic soybean', available in Aquaculture Nutrition Transgenic glyphosate tolerant soybeans are constituents of an industrial production system with specific agricultural practices and supplementary agrochemicals as interwoven additional elements. Thus the material produced should not be see...

MEGA - A search for μ → eγ

International Nuclear Information System (INIS)

Mischke, R.E.

1998-01-01

The MEGA experiment is a search for the decay μ → eγ. Even though there is no fundamental reason to expect lepton number to be a conserved quantity, processes such as μ → eγ have not been observed. (The present upper limit for the branching ratio for μ → eγ is 4.9 x 10 -11 .) The minimal standard model of electroweak interactions, which is enormously successful, builds in lepton number conservation. However, the decay μ → eγ is expected in many extensions to the standard model, in particular in supersymmetry models. The experimental signature for μ → eγ from decays at rest is the observation of a positron and photon, each of 52.8 MeV , that are back-to-back, in time coincidence, and originate from a common spatial point. The MEGA detector consists of two spectrometers designed to measure the kinematic characteristics of positrons and photons to search for events with this signature. The primary difficulty in the analysis of these data has been the development of reconstruction algorithms that balance efficiency and resolution. Also, many calibrations and corrections are needed to get optimum resolutions. Most surviving candidate events are accidentals. Results of analysis are given

Predictors of certification in infection prevention and control among infection preventionists: APIC MegaSurvey findings.

Science.gov (United States)

Kalp, Ericka L; Harris, Jeanette J; Zawistowski, Grace

2018-06-06

The 2015 APIC MegaSurvey was completed by 4,078 members to assess infection prevention practices. This study's purpose was to examine MegaSurvey results to relate infection preventionist (IP) certification status with demographic characteristics, organizational structure, compensation benefits, and practice and competency factors. Descriptive statistics were used to examine population characteristics and certification status. Bivariate logistic regression was performed to evaluate relationships between independent variables and certification status. Variables demonstrating statistical significance (P Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Mega sporting events: A poisoned chalice or a new dawn for low- and middle-income

Directory of Open Access Journals (Sweden)

Mark Tomlinson

2011-06-01

Full Text Available Mega sporting events in South Africa, which has the largest number of HIV-positive people in the world, and India, with 1.8 million deaths of children under 5 each year and 52 million stunted children, raise questions about the effective and, as importantly, the moral imperative of spending billions of dollars to host a sporting event. From a health perspective, selling alcohol and debt tarnishes further the notion of any intangible benefits of mega events to low- and middle-income countries.

Prevalência de megas em necrópsias realizadas no triângulo mineiro no período de 1954 a 1988

Directory of Open Access Journals (Sweden)

Edison Reis Lopes

1989-12-01

Full Text Available Dentre 1708 necrópsias de chagásicos crônicos, de um total de 4690, diagnosticamos 273 megas. Destes o mais freqüente foi o megacólon, seguido pelo megaesôfago, ocupando a associação megacólon e megaesôfago o terceiro lugar. Discutem-se e comparam-se os achados com outros de ordem clinico-epidemiológica e anatomopatológica. Confirmando dados da literatura, nossos achados atuais mostram, que a exemplo do que sucede na cardiopatia chagásica, o megacólon e o megaesôfago predominam no sexo masculino, discutindo-se os fatores que poderiam explicar a razão desse fato.

Multigenerational effects evaluation of the flame retardant tris(2-butoxyethyl) phosphate (TBOEP) using Daphnia magna.

Science.gov (United States)

Giraudo, Maeva; Dubé, Maxime; Lépine, Mélanie; Gagnon, Pierre; Douville, Mélanie; Houde, Magali

2017-09-01

Tris(2-butoxyethyl) phosphate (TBOEP) is an organophosphate ester used as substitute following the phase-out of brominated flamed retardants. Because of its high production volume and its use in a broad range of applications, this chemical is now frequently detected in the environment and biota. However, limited information is available on the long-term effects of TBOEP in aquatic organisms. In this study, Daphnia magna were exposed over three 21d generations to an environmentally relevant concentration of TBOEP (10μg/L) and effects were evaluated at the gene transcription, protein, and life-history (i.e., survival, reproduction and growth) levels. Chronic exposure to TBEOP did not impact survival or reproduction of D. magna but affected the growth output. The mean number of molts was also found to be lower in daphnids exposed to the chemical compared to control for a given generation, however there were no significant differences over the three generations. Molecular responses indicated significant differences in the transcription of genes related to growth, molting, ecdysteroid and juvenile hormone signaling, proteolysis, oxidative stress, and oxygen transport within generations. Levels of mRNA were also found to be significantly different for genes known to be involved in endocrine-mediated mechanisms such as reproduction and growth between generations F0, F1, and F2, indicating effects of parental exposure on offspring. Transcription results were supported by protein analyses with the significant decreased in catalase (CAT) activity in F1 generation, following the decreased transcription of cat in the parental generation. Taken together, these multi-biological level results suggest long-term potential endocrine disruption effects of TBOEP in D. magna exposed to an environmentally relevant concentration. This study highlights the importance of using chronic and multigenerational biological evaluation to assess risks of emerging chemicals. Crown Copyright �

Mega borg oil spill: Fate and effect studies

International Nuclear Information System (INIS)

1992-01-01

The Mega Borg, a Norwegian tanker, released an estimated 5.1 million gallons (gal) of Palanca Angola crude oil into the Gulf of Mexico during a lightering accident and subsequent fire. The collection of reports was designed to provide a comprehensive overview of the spill chronology, the fate of the oil released, and subsequent studies that were conducted to assess the impacts of the oil spill on the environment and its biota

Comparative evolutionary diversity and phylogenetic structure across multiple forest dynamics plots: a mega-phylogeny approach

Science.gov (United States)

Erickson, David L.; Jones, Frank A.; Swenson, Nathan G.; Pei, Nancai; Bourg, Norman A.; Chen, Wenna; Davies, Stuart J.; Ge, Xue-jun; Hao, Zhanqing; Howe, Robert W.; Huang, Chun-Lin; Larson, Andrew J.; Lum, Shawn K. Y.; Lutz, James A.; Ma, Keping; Meegaskumbura, Madhava; Mi, Xiangcheng; Parker, John D.; Fang-Sun, I.; Wright, S. Joseph; Wolf, Amy T.; Ye, W.; Xing, Dingliang; Zimmerman, Jess K.; Kress, W. John

2014-01-01

Forest dynamics plots, which now span longitudes, latitudes, and habitat types across the globe, offer unparalleled insights into the ecological and evolutionary processes that determine how species are assembled into communities. Understanding phylogenetic relationships among species in a community has become an important component of assessing assembly processes. However, the application of evolutionary information to questions in community ecology has been limited in large part by the lack of accurate estimates of phylogenetic relationships among individual species found within communities, and is particularly limiting in comparisons between communities. Therefore, streamlining and maximizing the information content of these community phylogenies is a priority. To test the viability and advantage of a multi-community phylogeny, we constructed a multi-plot mega-phylogeny of 1347 species of trees across 15 forest dynamics plots in the ForestGEO network using DNA barcode sequence data (rbcL, matK, and psbA-trnH) and compared community phylogenies for each individual plot with respect to support for topology and branch lengths, which affect evolutionary inference of community processes. The levels of taxonomic differentiation across the phylogeny were examined by quantifying the frequency of resolved nodes throughout. In addition, three phylogenetic distance (PD) metrics that are commonly used to infer assembly processes were estimated for each plot [PD, Mean Phylogenetic Distance (MPD), and Mean Nearest Taxon Distance (MNTD)]. Lastly, we examine the partitioning of phylogenetic diversity among community plots through quantification of inter-community MPD and MNTD. Overall, evolutionary relationships were highly resolved across the DNA barcode-based mega-phylogeny, and phylogenetic resolution for each community plot was improved when estimated within the context of the mega-phylogeny. Likewise, when compared with phylogenies for individual plots, estimates of

Modern Integration Processes in the Asia-Pacific Region: the Formation of Trans-Regional Mega-Agreements

Directory of Open Access Journals (Sweden)

Maliuta Iryna A.

2017-12-01

Full Text Available In the 21st century, especially in the last decade, new intercontinental integration projects appear on the global stage with a high potential for influencing the regional economic structure and at the same time bearing certain challenges for the international geo-economic and geo-political map of the world. Comprehensive new-generation inter-regional agreements are being formed, such as the TTP, the TTIP, the RCEP, the Comprehensive Economic and Trade Agreement between Canada and the EU (CETA, the Japan-EU Economic Partnership. The Asia-Pacific region has been an active participant in the creation and promotion of mega-regional trade agreements. Mega-regional trade agreements in the Asia-Pacific region, namely the TTP and the RCEP, are analyzed as mega-projects with an unprecedented scale of liberalization within the framework of the agreement that include provisions complementing the WTO framework or extending beyond it. There identified reasons for the emergence of mega-regional trade agreements and prospects for the implementation of these projects, as well as possible consequences for the international economic system. It is established that new trans-regional projects, providing certain advantages to the participating countries, simultaneously carry both opportunities and challenges for the world economy. The latter are associated with the threats of crowding the countries that do not take an active part in the integration processes out of the global chains of value creation as well as of the processes of international trade.

Ecotoxicological assessment of grey water treatment systems with Daphnia magna and Chironomus riparius.

Science.gov (United States)

Hernández Leal, L; Soeter, A M; Kools, S A E; Kraak, M H S; Parsons, J R; Temmink, H; Zeeman, G; Buisman, C J N

2012-03-15

In order to meet environmental quality criteria, grey water was treated in four different ways: 1) aerobic 2) anaerobic+aerobic 3) aerobic+activated carbon 4) aerobic+ozone. Since each treatment has its own specific advantages and disadvantages, the aim of this study was to compare the ecotoxicity of differently treated grey water using Chironomus riparius (96 h test) and Daphnia magna (48 h and 21d test) as test organisms. Grey water exhibited acute toxicity to both test organisms. The aerobic and combined anaerobic+aerobic treatment eliminated mortality in the acute tests, but growth of C. riparius was still affected by these two effluents. Post-treatment by ozone and activated carbon completely removed the acute toxicity from grey water. In the chronic toxicity test the combined anaerobic+aerobic treatment strongly affected D. magna population growth rate (47%), while the aerobic treatment had a small (9%) but significant effect. Hence, aerobic treatment is the best option for biological treatment of grey water, removing most of the toxic effects of grey water. If advanced treatment is required, the treatment with either ozone or GAC were shown to be very effective in complete removal of toxicity from grey water. Copyright © 2011 Elsevier Ltd. All rights reserved.

Parasitism drives host genome evolution: Insights from the Pasteuria ramosa-Daphnia magna system.

Science.gov (United States)

Bourgeois, Yann; Roulin, Anne C; Müller, Kristina; Ebert, Dieter

2017-04-01

Because parasitism is thought to play a major role in shaping host genomes, it has been predicted that genomic regions associated with resistance to parasites should stand out in genome scans, revealing signals of selection above the genomic background. To test whether parasitism is indeed such a major factor in host evolution and to better understand host-parasite interaction at the molecular level, we studied genome-wide polymorphisms in 97 genotypes of the planktonic crustacean Daphnia magna originating from three localities across Europe. Daphnia magna is known to coevolve with the bacterial pathogen Pasteuria ramosa for which host genotypes (clonal lines) are either resistant or susceptible. Using association mapping, we identified two genomic regions involved in resistance to P. ramosa, one of which was already known from a previous QTL analysis. We then performed a naïve genome scan to test for signatures of positive selection and found that the two regions identified with the association mapping further stood out as outliers. Several other regions with evidence for selection were also found, but no link between these regions and phenotypic variation could be established. Our results are consistent with the hypothesis that parasitism is driving host genome evolution. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Is acetylcholinesterase a biomarker of susceptibility in Daphnia magna (Crustacea, Cladocera) after deltamethrin exposure?

Science.gov (United States)

Toumi, Héla; Boumaiza, Moncef; Millet, Maurice; Radetski, Claudemir Marcos; Felten, Vincent; Férard, Jean François

2015-02-01

In the present study, we explored the possibility of using the acetylcholinesterase (AChE) as a biomarker after deltamethrin (pyrethroid insecticide) exposure with three strains of the cladoceran Daphnia magna. Four calculated time-weighted deltamethrin concentrations (20.1, 40.3, 80.6 and 161.3 ng L(-1)) were compared against control acetylcholinesterase activity. Our results showed that after 48 h of deltamethrin exposure, all treatments induced a significant decrease of AChE activities whatever the three considered strains. However, diverse responses were registered in terms of lowest observed effect concentrations (LOEC: 80.6 ng L(-1) for strain 1 and 20.1 ng L(-1) for strains 2 and 3) revealing differences in sensitivity among the three tested strains of D. magna. Our results suggest that after deltamethrin exposure, the AChE activity responses can be also used as a biomarker of susceptibility (i.e., variation of strain specific response). Moreover, our results show that strain 1 is the less sensitive in terms of IC50-48 h of AChE, whereas it became the most sensitive when considering the EC50-48 h estimated in the standard ecotoxicity test. Copyright © 2014 Elsevier Ltd. All rights reserved.

Results from beam tests of MEGA's low-mass, high-rate cylindrical MWPCs

International Nuclear Information System (INIS)

Stanislaus, S.; Armijo, V.; Black, J.K.; Bolton, R.D.; Carius, S.; Cooper, M.D.; Espinoza, C.; Hart, G.; Hogan, G.; Gonzales, A.; Mischke, R.E.; Piilonen, L.E.; Sandoval, J.; Schilling, S.; Sena, J.; Suazo, G.; Szymanski, J.J.; Whitehouse, D.A.; Wilkinson, C.A.; Fisk, R.; Koetke, D.D.; Manweiler, R.W.; Jui, C.C.

1991-01-01

One of the leading experimental projects at LAMPF has been the MEGA experiment. This is an experiment to search for the rare decay μ → eγ with a sensitivity of 10 -13 . A prime component of this project has been the design and construction of high-rate, low mass MWPCs for the tracking of positrons from muon decay. With rate capabilities of 2 x 10 4 e + /mm 2 /s and a thickness of 3 x 10 -4 radiation lengths, these chambers are state-of-the-art cylindrical MWPCs. Cylindrical chambers of this size (0.9 m 2 ) and thinness have never been previously constructed. The MEGA project at LAMPF has recently succeeded in building chambers with these necessary performance characteristics as demonstrated by data taken from muon decays, cosmic rays, and sources

Sucralose induces biochemical responses in Daphnia magna.

Directory of Open Access Journals (Sweden)

Ann-Kristin Eriksson Wiklund

Full Text Available The intense artificial sweetener sucralose has no bioconcentration properties, and no adverse acute toxic effects have been observed in standard ecotoxicity tests, suggesting negligible environmental risk. However, significant feeding and behavioural alterations have been reported in non-standard tests using aquatic crustaceans, indicating possible sublethal effects. We hypothesized that these effects are related to alterations in acetylcholinesterase (AChE and oxidative status in the exposed animals and investigated changes in AChE and oxidative biomarkers (oxygen radical absorbing capacity, ORAC, and lipid peroxidation, TBARS in the crustacean Daphnia magna exposed to sucralose (0.0001-5 mg L(-1. The sucralose concentration was a significant positive predictor for ORAC, TBARS and AChE in the daphnids. Moreover, the AChE response was linked to both oxidative biomarkers, with positive and negative relationships for TBARS and ORAC, respectively. These joint responses support our hypothesis and suggest that exposure to sucralose may induce neurological and oxidative mechanisms with potentially important consequences for animal behaviour and physiology.

Assessment of MEGA BORG impacts on sea turtles

International Nuclear Information System (INIS)

Gitschlag, G.

1993-01-01

Studies were conducted to assess the impacts of the MEGA BORG oil spill on sea turtles in the path of the oil plume. Aerial surveys were performed to determine the presence of turtles and provide a gross visual assessment of potential impacts. Although extensive efforts were made to capture sea turtles around oil and gas platforms only one loggerhead sea turtle, Caretta caretta, was captured. Neither external visual inspection nor laboratory fecal analysis showed evidence of petroleum contamination

Comportamento do peso do coração e do corpo em chagásicos crônicos com e sem "megas"

Directory of Open Access Journals (Sweden)

Hipólito de Oliveira Almeida

1980-12-01

Full Text Available O peso do coração é menor nos chagásicos com "megas" do que nos falecidos subitamente ou em I.C.C., sendo, porém, maior que nos controles. Já o peso corporal ésemelhante nos chagásicos falecidos subitamente e nos controles, havendo redução moderada no grupo com I.C.C., e rtiais acentuada nos chagásicos com "megas" (redução de 20% em relação aos controles. A relação percentual peso cardíaco/peso corporal é de 1,1% no grupo com I.C.C.; 0,71% no grupo de morte súbita; 0,77% no grupo com "megas"; 0,49% no grupo controle e 0,60% ne grupo de doenças caquetizantes. Com base nas médias dos pesos cardíacos e corporal dos grupos controle, de doenças caquetizantes e de megas, calculou-se que o emagrecimento ocorrido nos megas reduziria o peso cardíaco médio de apenas 6,8%.

Treasure Chase: Mega Gifts Are Down--But Are They out?

Science.gov (United States)

Mayer, Caroline E.

2010-01-01

Just a few years ago, the University of Notre Dame averaged about six mega gifts--$10 million or more--a year. Last year, however, the Fighting Irish received only one such donation. "That multimillion donation has become more difficult to obtain," says Lou Nanni, vice president for university relations at the Indiana institution.…

Evaluation of Baffle Fixes Film up Flow Sludge Blanket Filtration (BFUSBF) System in Treatment of Wastewaters from Phenol and 2,4-Dinitrophenol Using Daphnia Magna Bioassay

OpenAIRE

Mohammad Javad Ghannadzadeh; Ahmad Jonidi Jafari; Abbas Rezaee; Fatemeh Eftekharian; Ali Koolivand

2016-01-01

Background: Phenol and nitrophenol are common compounds found in different types of industrial wastewater known as serious threats to human health and natural environment. In this study, Daphnia magna was used to evaluate the effectiveness of "baffle fixes film up flow sludge blanket filtration" (BFUSBF) system in elimination of phenolic compounds from water. Methods: D. magna cultures were used as toxicity index of phenol and 2,4-DNP mixtures after treatment by a pilot BFUSBF system which...

Trans-generational effects induced by alpha and gamma ionizing radiations at Daphnia magna

International Nuclear Information System (INIS)

Parisot, Florian

2015-01-01

Anthropogenic activities related to the nuclear industry contribute to continuous discharges of radionuclides into terrestrial and aquatic ecosystems. Over the past decades, the ecological risk of ionizing radiation has become a growing public, regulatory and scientific concern for ecosystems protection. Until recently, only few studies focus on exposure situations at low doses of irradiation, although these situations are representative of realistic environmental conditions. Understanding how ionizing radiation affects species over several generations and at various levels of biological organization is a major research goal in radioecology. The aim of this PhD was to bring new knowledge on the effects of ionizing radiation during a multi-generational expose of the aquatic invertebrate, Daphnia magna. A two-step strategy was implemented. First, an external gamma radiation at environmentally relevant dose rates was performed on D. magna over three successive generations (F0, F1 and F2). The objective of this experiment was to examine whether low dose rates of radiation induced increasing effects on survival, growth and reproduction of daphnids over generations and to test a possible accumulation and transmission of DNA alterations from adults to offspring. Results showed an accumulation and a transmission of DNA alterations over generations, together with an increase in effect severity on growth and reproduction from generation F0 to generation F2. Transiently more efficient DNA repair leading to some recovery at the organism level was suggested in generation F1. Second, data from the external gamma irradiation and those from an earlier study of internal alpha contamination were analyzed with DEBtox models (Dynamic Energy Budget applied to toxicology), to identify and compare the causes of the trans-generational increase in effect severity between the two types of radiation. In each case, two distinct metabolic modes of action were necessary to explain effects on

Long-term evaluation of lethal and sublethal toxicity of industrial effluents using Daphnia magna and Moina macrocopa.

Science.gov (United States)

Yi, Xianliang; Kang, Sung-Wook; Jung, Jinho

2010-06-15

Acute toxicity and feeding rate inhibition of effluent from a wastewater treatment plant and its adjacent stream water on Daphnia magna and Moina macrocopa were comparatively studied. The acute toxicity of the final effluent (FE) fluctuated greatly over the sampling period from January to August 2009. Toxicity identification results of the FE in July 2009 showed that Cu originating from the Fenton's reagent was likely a key toxicant. In addition, the feeding rate of both species was still inhibited by the FEs in which acute toxicity was not observed. These findings indicate that the feeding response would be a useful tool for monitoring sublethal effects of industrial effluents. For the acute toxicity test, M. macrocopa was more sensitive than D. magna, but the opposite result was true in the case of the feeding rate inhibition. These suggest that different species have different sensitivities to toxic chemicals and to the test methods. Copyright 2010 Elsevier B.V. All rights reserved.

The effects of the MEGA BORG spill on Gulf of Mexico shrimp

International Nuclear Information System (INIS)

Nance, J.

1993-01-01

A brown shrimp stock model was developed at the NMFS Galveston Laboratory to assess the effects of the MEGA BORG oil spill on the brown shrimp population along the Texas coast. Water and sediment samples from near the MEGA BORG spill area were collected and analyzed by the Geochemical and Environmental Research Group at Texas A ampersand M University. Hydrocarbon concentrations found at the sediment collection stations ranged from 1.38 ug/g to 7.42 ug/g, while concentrations at the water column sampling sites ranged from 0.69 ug/l to 27.39 ug/l. Evaluation of chromatograms and analytical data suggested that sediments from the area contained primarily biogenic hydrocarbons. Only one station had elevated hydrocarbon levels. However, these values were only three to five times higher than the concentrations measured at the other stations. Evaluation of the water samples from the area showed only very low concentration levels of hydrocarbons were present in the water column. A bioassay study was conducted by the US Environmental Protection Agency, Environmental Research Laboratory in Gulf Breeze, Florida. The main conclusion from the bioassay study was that the concentrations of hydrocarbons measured at the field sites where water samples were taken tended to be three orders of magnitude lower than the hydrocarbon concentrations causing toxic responses in mysid and white shrimp. There were no detected effects of the brown shrimp population along the Texas coast from the MEGA BORG oil spill

Current results for μ→e+γ decay search with the MEGA experiment

International Nuclear Information System (INIS)

Zhang, Y.

1993-01-01

The MEGA experiment at LAMPF is designed to search for the rare decay μ → e+γ with a branching ratio sensitivity of 4x10 -13 . The detector consists of an electron spectrometer (a set of low-mass MPWCs and two barrels of scintillators) and a photon arm (three-layer pair spectrometer) in a 1.5-T solenoidal magnetic field. The experimental design maximizes rate capability, retains large solid angle, and suppresses the background to below the experimental sensitivity. In the summer of 1992, the MEGA collaboration successfully finished whole-system tests and got 163.6 million μ→E+γ candidate events by using the electron arm and two of the three photon pair spectrometers. The status of the data analysis will be described

Megacity Indicator System for Disaster Risk Management in Istanbul (MegaIST)

Science.gov (United States)

Yahya Menteşe, Emin; Kılıç, Osman; Baş, Mahmut; Khazai, Bijan; Ergün Konukcu, Betul; Emre Basmacı, Ahmet

2017-04-01

Decision makers need tools to understand the priorities and to set up benchmarks and track progress in their disaster risk reduction activities, so that they can justify their decisions and investments. In this regard, Megacity Indicator System for Disaster Risk Management (MegaIST), is developed in order to be used in disaster risk management studies, for decision makers and managers to establish right strategies and proper risk reduction actions, enhance resource management and investment decisions, set priorities, monitor progress in DRM and validate decisions taken with the aim of helping disaster oriented urban redevelopment, inform investors about risk profile of the city and providing a basis for dissemination and sharing of risk components with related stakeholders; by Directorate of Earthquake and Ground Research of Istanbul Metropolitan Municipality (IMM). MegaIST achieves these goals by analyzing the earthquake risk in three separate but complementary sub-categories consisting of "urban seismic risk, coping capacity and disaster risk management index" in an integrated way. MegaIST model fosters its analyses by presenting the outputs in a simple and user friendly format benefiting from GIS technology that ensures the adoptability of the model's use. Urban seismic risk analysis includes two components, namely; Physical Risk and Social Vulnerability Analysis. Physical risk analysis is based on the possible physical losses (such as building damage, casualties etc.) due to an earthquake while social vulnerability is considered as a factor that increases the results of the physical losses in correlation with the level of education, health, economic status and disaster awareness/preparedness of society. Coping capacity analysis is carried out with the aim of understanding the readiness of the Municipality to respond and recover from a disaster in Istanbul can be defined both in terms of the Municipality's operational capacities - the capacity of the

Comparative ecotoxicity of potential biofuels to water flea (Daphnia magna), zebrafish (Danio rerio) and Chinese hamster (Cricetulus griseus) V79 cells.

Science.gov (United States)

Heger, Sebastian; Du, Miaomiao; Bauer, Kevin; Schäffer, Andreas; Hollert, Henner

2018-08-01

The ecotoxicity of two biofuel candidates (1‑octanol and 2‑butanone) was investigated by an integrative test strategy using three bioassays: the acute immobilisation test with water flea (D. magna), the fish embryo acute toxicity test with zebrafish (Danio rerio) and the in vitro micronucleus assay with Chinese hamster (Cricetulus griseus) V79 cells. The median effective concentration (EC 50 ) values were 14.9±0.66mgL -1 for 1‑octanol, and 2152.1±44.6mgL -1 for 2‑butanone in the D. magna test. Both 1‑octanol and 2‑butanone caused teratogenic and lethal effects on zebrafish embryos, while exposure to 1‑octanol significantly induced these effects at concentrations ≥2.0mgL -1 . These results indicate that 1‑octanol exert much higher ecotoxicity than 2‑butanone to D. magna and zebrafish embryos. Moreover, both 1‑octanol and 2‑butanone did not cause significant genotoxic effects, while their metabolites significantly induced micronuclei in V79 cells. The present study proposed an integrative test approach to evaluate the potential ecotoxicity of biofuels using simple, quick and inexpensive bioassays. Copyright © 2018 Elsevier B.V. All rights reserved.

Silver nanoparticles and silver nitrate induce high toxicity to Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio

International Nuclear Information System (INIS)

Ribeiro, Fabianne; Gallego-Urrea, Julián Alberto; Jurkschat, Kerstin; Crossley, Alison; Hassellöv, Martin; Taylor, Cameron; Soares, Amadeu M.V.M.; Loureiro, Susana

2014-01-01

Silver nanoparticles (AgNP) have gained attention over the years due to the antimicrobial function of silver, which has been exploited industrially to produce consumer goods that vary in type and application. Undoubtedly the increase of production and consumption of these silver-containing products will lead to the entry of silver compounds into the environment. In this study we have used Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio as model organisms to investigate the toxicity of AgNP and AgNO 3 by assessing different biological endpoints and exposure periods. Organisms were exposed following specific and standardized protocols for each species/endpoints, with modifications when necessary. AgNP were characterized in each test-media by Transmission Electron Microscopy (TEM) and experiments were performed by Dynamic Light Scattering (DLS) to investigate the aggregation and agglomeration behavior of AgNP under different media chemical composition and test-period. TEM images of AgNP in the different test-media showed dissimilar patterns of agglomeration, with some agglomerates inside an organic layer, some loosely associated particles and also the presence of some individual particles. The toxicity of both AgNO 3 and AgNP differ significantly based on the test species: we found no differences in toxicity for algae, a small difference for zebrafish and a major difference in toxicity for Daphnia magna. - Highlights: •Effects of silver nanoparticles and nitrate were compared in three aquatic species. •The presence of food on the immobilization assay for Daphnia magna significantly decreased AgNP toxicity. •AgNP and AgNO 3 differ in toxicity according to the test species and endpoint. •AgNP and AgNO 3 induced dissimilar abnormalities on zebrafish embryos' development. •AgNP behavior in the test media will rule its bioavailability and uptake and therefore toxicity

Silver nanoparticles and silver nitrate induce high toxicity to Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Fabianne, E-mail: ribeiro.f@ua.pt [Department of Biology and CESAM, University of Aveiro. Campus Universitario de Santiago, 3810-193. Aveiro (Portugal); Gallego-Urrea, Julián Alberto [Department of Chemistry and Molecular Biologyx, University of Gothenburg, Kemivägen 4, 41296 Gothenburg (Sweden); Jurkschat, Kerstin; Crossley, Alison [Department of Materials, Oxford University Begbroke Science Park OX5 1PF (United Kingdom); Hassellöv, Martin [Department of Chemistry and Molecular Biologyx, University of Gothenburg, Kemivägen 4, 41296 Gothenburg (Sweden); Taylor, Cameron [Department of Materials, Oxford University Begbroke Science Park OX5 1PF (United Kingdom); Soares, Amadeu M.V.M.; Loureiro, Susana [Department of Biology and CESAM, University of Aveiro. Campus Universitario de Santiago, 3810-193. Aveiro (Portugal)

2014-01-01

Silver nanoparticles (AgNP) have gained attention over the years due to the antimicrobial function of silver, which has been exploited industrially to produce consumer goods that vary in type and application. Undoubtedly the increase of production and consumption of these silver-containing products will lead to the entry of silver compounds into the environment. In this study we have used Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio as model organisms to investigate the toxicity of AgNP and AgNO{sub 3} by assessing different biological endpoints and exposure periods. Organisms were exposed following specific and standardized protocols for each species/endpoints, with modifications when necessary. AgNP were characterized in each test-media by Transmission Electron Microscopy (TEM) and experiments were performed by Dynamic Light Scattering (DLS) to investigate the aggregation and agglomeration behavior of AgNP under different media chemical composition and test-period. TEM images of AgNP in the different test-media showed dissimilar patterns of agglomeration, with some agglomerates inside an organic layer, some loosely associated particles and also the presence of some individual particles. The toxicity of both AgNO{sub 3} and AgNP differ significantly based on the test species: we found no differences in toxicity for algae, a small difference for zebrafish and a major difference in toxicity for Daphnia magna. - Highlights: •Effects of silver nanoparticles and nitrate were compared in three aquatic species. •The presence of food on the immobilization assay for Daphnia magna significantly decreased AgNP toxicity. •AgNP and AgNO{sub 3} differ in toxicity according to the test species and endpoint. •AgNP and AgNO{sub 3} induced dissimilar abnormalities on zebrafish embryos' development. •AgNP behavior in the test media will rule its bioavailability and uptake and therefore toxicity.

QUALIDADE MICROBIOLÓGICA DA ÁGUA DE CHUVA ARMAZENADA EM CISTERNAS NA ÁREA RURAL DE INHAMBUPE, NO SEMIÁRIDO BAIANO, E SEUS FATORES INTERVENIENTES

OpenAIRE

Nara de Melo Dantas Silva; Louisa Wessels Perello; Luiz Roberto Santos Moraes

2014-01-01

Com a existência da problemática de carência hídrica no Semiárido Brasileiro devido aos fatores climáticos e edáficos, o sistema de captação e armazenamento de água de chuva, mostra-se como uma solução para o abastecimento de água, melhorando a qualidade de vida dos habitantes das regiões semiáridas, inclusive dos moradores de Inhambupe. Ao estudar os fatores intervenientes da água de chuva armazenada em cisternas da zona rural do município de Inhambupe, pode-se concluir que existe a possibil...

Mega-event strategy as a tool of urban transformation : Sydney's experience

NARCIS (Netherlands)

Chen, Y.; Spaans, M.

2009-01-01

Mega-event strategies and their impact on host cities have drawn increasing interest, as organising large-scale urban events has become part of a deliberate urban policy strategy to promote local economic growth and put the host city on the world agenda. Thus far, the research addressing what

Sustainability as Global Norm: The Greening of Mega-Events in China

NARCIS (Netherlands)

Mol, A.P.J.; Zhang, L.

2011-01-01

This volume explores sports mega-events, their social, political, and cultural characters, the value systems that they inscribe and draw on, the claims they make on us and the claims the organisers make for them, the spatial and ethical relationships they create, and the responses of civil societies

Ground-level air pollution changes during a boreal wildland mega-fire

Science.gov (United States)

Andrzej Bytnerowicz; Yu-Mei Hsu; Kevin Percy; Allan Legge; Mark E. Fenn; Susan Schilling; Witold Frączek; Diane Alexander

2016-01-01

The 2011 Richardson wildland mega-fire in the Athabasca Oil Sands Region (AOSR) in northern Alberta, Canada had large effects on air quality. At a receptor site in the center of the AOSR ambient PM2.5, O3, NO, NO2, SO2, NH3, HONO, HNO3...

Research of acute influence of new fertlizer «Rost-concentrate» on the hydrobionts Сyprinus carpio L. and Daphnia magna Straus

Directory of Open Access Journals (Sweden)

N. Tson

2016-12-01

Full Text Available Purpose. To establish and assess acute toxicity parameters of "ROST-concentrate (10+7+7" acute toxicity for planktonic crustacean Daphnia magna Straus and carp fingerlings Cyprinus carpio L. Methodology."ROST-concentrate (10+7+7" contains macronutrients (nitrogen, phosphorus, potassium, which are valuable for the pond ecosystem, and trace elements in environmentally safe chelate form. We determined the vital (LC0, absolutely lethal (LC100 and median (LC50 drug concentrations on the test organisms such as crustacean D. magna (Cladocera and carp fingerlings C. carpio. The determination of acute lethal toxicity on D. magna was conducted according to DSTU 4173: 2003 that corresponded to the international standard ISO 6341: 2012, MOD [7]. The temperature of the experiment was 20±0.5 oC. The exposure time - 96 hours. Daphnia were not fed. Following "ROST-concentrate (10+7+7" concentrations were tested: 100; 75; 50; 25; 10; 1; 0.5; 0.1; 0.05; 0.01; 0,005; 0,001 ml/dm3. We also determined the acute lethal toxicity on carp fingerings with an average weight of 6.78±0.63 grams following the standardized procedure [8]. Pond water was used in the experiment. Ten fish were placed into a 40 L aquarium. Following concentrations of "ROST-concentrate (10+7+7" were investigated: 0,5; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 15; 20; 30; 40 mg/L. The exposure time was 24 hours. Water temperature was 19±1oC. LC50 drug median concentration was calculated according to G. Kerber method. Findings. The parameters of integral acute toxicity of "ROST-concentrate (10+7+7" on typical organisms of fish pond ecosystems.With 96 h exposure on juvenile cladoceran D. magna, lethal concentration was LC100 = 5,00 ml/dm3, median concentration was LC50 = 0,15 ml/dm3, vital concentration was LC0 = 0,01 ml/dm3. According to the classification of toxic substances, the "ROST-concentrate (10+7+7" is characterized by low toxicity on juvenile cladoceran D. magna. With 24 h exposure on carp

Air pollution and its impact on human health in mega cities

International Nuclear Information System (INIS)

Ali, I.

1999-01-01

One of the major problems faced by the over crowded mega-cities of the world in general and that in third world is the alarming levels of air pollution causing damage to the health of its inhabitants. In Cairo estimated lives lost annually due to air pollution varies between 4000 to 16000 while Delhi has been rated as the most polluted city in the world. Karachi now a mega-city typically represents pollution status of the third world. Major cause of pollution is more than 0.62 millions vehicles on the roads. The pollution due to industries is localized and mainly affects the health of the workers. Measurement carried out for the selected areas along the roads carrying high density traffic show a very high pollution level (CO, 3 to 10 ppm; CO/sub 2/,170 to 350 ppm; HC 0.274 to 0.360 vol. %; particulate matter 67.0 to 565.5 ug/m/sup 3/. A parallel hospital survey to correlate air borne disease with air pollution indicates that over 16600 to 22977 patients suffered from air borne diseases while 6377 from bacterial infection. Analysis showed that 70% of the patients suffering from airborne disease come from the surveyed areas with high level pollution. Cancer is shifting from old age to middle age group indicating deteriorating air environment. Ratio of male to female patients is 2:1, which is indicative of hazardous ambient air quality outside to which men are exposed more than women. The paper discusses in depth the air pollution and its impact on human health in mega cities with Karachi as a case study. (author)

The Effect of Fermentation Time with Probiotic Bacteria on Organic Fertilizer as Daphnia magna Cultured Medium towards Nutrient Quality, Biomass Production and Growth Performance Enhancement

Science.gov (United States)

Endar Herawati, Vivi; Agung Nugroho, Ristiawan; Pinandoyo; Darmanto, YS; Hutabarat, Johannes

2018-02-01

The nutrient quality and growth performance of D. magna are highly depend on the organic fertilizer which is used in its culture medium. The objective of this study was to identify the best fermentation time by using probiotic bacteria on organic fertilizer as mass culture medium to improve its nutrient quality, biomass production, and growth performance. This study was conducted using completely randomized experimental design with five treatments and three repetitions. Organic fertilizers used cultured medium with chicken manure, rejected bread and tofu waste fermented by probiotic bacteria then cultured for 0, 7, 14, 21 and 28 days. The results showed that medium which used 25% chicken manure, 25% tofu waste and 50% rejected bread cultured for 28 days created the highest biomass production, population density and nutrient content of D. magna those are 233,980 ind/L for population density; 134.60 grams for biomass production, 0.574% specific growth rate; 68.06% protein content and 6.91% fat. The highest fatty acid profile is 4.83% linoleic and 3.54% linolenic acid. The highest essential amino acid is 53.94 ppm lysine. In general, the content of ammonia, DO, temperature, and pH during the study were in the good range of D. magna life. The conclusion of this research is medium which used 25% chicken manure, 25% tofu waste and 50% rejected bread cultured for 28 days created the highest biomass production, population and nutrient content of D. magna.

Prevalência de megas em necrópsias realizadas no triângulo mineiro no período de 1954 a 1988

Directory of Open Access Journals (Sweden)

Edison Reis Lopes

1989-12-01

Full Text Available Dentre 1708 necrópsias de chagásicos crônicos, de um total de 4690, diagnosticamos 273 megas. Destes o mais freqüente foi o megacólon, seguido pelo megaesôfago, ocupando a associação megacólon e megaesôfago o terceiro lugar. Discutem-se e comparam-se os achados com outros de ordem clinico-epidemiológica e anatomopatológica. Confirmando dados da literatura, nossos achados atuais mostram, que a exemplo do que sucede na cardiopatia chagásica, o megacólon e o megaesôfago predominam no sexo masculino, discutindo-se os fatores que poderiam explicar a razão desse fato.One thousand seven hundred and eight chronic chagasic post-mortem examinations studied from a total of4690 autopsies perfomed at our Institution. Two hundred and seventy-three chagasic had megas. Megacolon was the most frequent, followed by megaesophagus. Megacolon associated with megaesophagus was, the third mostcommom finding. Our data are discussed and compared with the literature. Megacolon and megaesophagus were more prevalent in man, as shown by other workers. Higher parasitemia perhaps could explain this finding.

Investigating fusion plasma instabilities in the Mega Amp Spherical Tokamak using mega electron volt proton emissions (invited)

Energy Technology Data Exchange (ETDEWEB)

Perez, R. V., E-mail: rvale006@fiu.edu; Boeglin, W. U.; Angulo, A.; Avila, P.; Leon, O.; Lopez, C. [Department of Physics, Florida International University, 11200 SW 8 ST, CP204, Miami, Florida 33199 (United States); Darrow, D. S. [Princeton Plasma Physics Laboratory, James Forrestal Campus, P.O. Box 451, Princeton, New Jersey 08543 (United States); Cecconello, M.; Klimek, I. [Department of Physics and Astronomy, Uppsala University, Uppsala SE-751 20 (Sweden); Allan, S. Y.; Akers, R. J.; Keeling, D. L.; McClements, K. G.; Scannell, R.; Conway, N. J. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Turnyanskiy, M. [ITER Physics Department, EFDA CSU Garching, Boltzmannstrasse 2, D-85748, Garching (Germany); Jones, O. M. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Michael, C. A. [Australian National University, Canberra ACT 0200 (Australia)

2014-11-15

The proton detector (PD) measures 3 MeV proton yield distributions from deuterium-deuterium fusion reactions within the Mega Amp Spherical Tokamak (MAST). The PD’s compact four-channel system of collimated and individually oriented silicon detectors probes different regions of the plasma, detecting protons (with gyro radii large enough to be unconfined) leaving the plasma on curved trajectories during neutral beam injection. From first PD data obtained during plasma operation in 2013, proton production rates (up to several hundred kHz and 1 ms time resolution) during sawtooth events were compared to the corresponding MAST neutron camera data. Fitted proton emission profiles in the poloidal plane demonstrate the capabilities of this new system.

Symbiotic bacteria contribute to increasing the population size of a freshwater crustacean, Daphnia magna.

Science.gov (United States)

Peerakietkhajorn, Saranya; Tsukada, Koji; Kato, Yasuhiko; Matsuura, Tomoaki; Watanabe, Hajime

2015-04-01

The filter-feeding crustacean Daphnia is a key organism in freshwater ecosystems. Here, we report the effect of symbiotic bacteria on ecologically important life history traits, such as population dynamics and longevity, in Daphnia magna. By disinfection of the daphniid embryos with glutaraldehyde, aposymbiotic daphniids were prepared and cultured under bacteria-free conditions. Removal of bacteria from the daphniids was monitored by quantitative polymerase chain reaction for bacterial 16S rRNA gene. The population of aposymbiotic daphniids was reduced 10-folds compared with that of the control daphniids. Importantly, re-infection with symbiotic bacteria caused daphniids to regain bacteria and increase their fecundity to the level of the control daphniids, suggesting that symbiotic bacteria regulate Daphnia fecundity. To identify the species of symbiotic bacteria, 16S rRNA genes of bacteria in daphniids were sequenced. This revealed that 50% of sequences belonged to the Limnohabitans sp. of the Betaproteobacteria class and that the diversity of bacterial taxa was relatively low. These results suggested that symbiotic bacteria have a beneficial effect on D. magna, and that aposymbiotic Daphnia are useful tools in understanding the role of symbiotic bacteria in the environmental responses and evolution of their hosts. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

Trophic transfer of differently functionalized zinc oxide nanoparticles from crustaceans (Daphnia magna) to zebrafish (Danio rerio)

DEFF Research Database (Denmark)

Skjolding, Lars Michael; Winther-Nielsen, M.; Baun, Anders

2014-01-01

) higher than toxic levels reported for zinc in D. magna. Consequently, the zinc recovered in the animals was not solely due to soluble zinc, but agglomerates/aggregates of ZnO NP or ZnO-octyl NP contributed to the body burdens. The trophic transfer study showed uptake of both ZnO NP and ZnO-octyl NP...

Gas and Dust Phenomena of Mega-earthquakes and the Cause

Science.gov (United States)

Yue, Z.

2013-12-01

A mega-earthquake suddenly releases a large to extremely large amount of kinetic energy within a few tens to two hundreds seconds and over ten to hundreds kilometer distances in the Earth's crust and on ground surface. It also generates seismic waves that can be received globally and co-seismic ground damages such co-seismic ruptures and landslides. However, such vast, dramatic and devastating kinetic actions in the Earth's crustal rocks and on the ground soils cannot be known or predicted by people at few weeks, days, hours, or minutes before they are happening. Although seismologists can develop and use seismometers to report the locations and magnitudes of earthquakes within minutes of their occurrence, they cannot predict earthquakes at present. Therefore, damage earthquakes have caused and would continue to cause huge disasters, fatalities and injuries to our human beings. This problem may indicate that it is necessary to re-examine the cause of mega-earthquakes in addition to the conventional cause of active fault elastic rebounding. In the last ten years, many mega-earthquakes occurred in China and around the Pacific Ocean and caused many casualties to human beings and devastating disasters to environments. The author will give a brief review on the impacts of the mega-earthquakes happened in recent years. He will then present many gas and dust related phenomena associated with the sudden occurrences of these mega earthquakes. They include the 2001 Kunlunshan Earthquake M8.1, 2008 Wenchuan Earthquake M8.0 and the 2010 Yushu Earthquake M7.1 in China, the 2010 Haiti Earthquake M7.0, the 2010 Mexicali Earthquake M7.2, the 2010 Chile Earthquake M8.8, the 2011 Christchurch earthquake M6.3 and the 2011 Japan Earthquake M9.0 around the Pacific Ocean. He will discuss the cause of these gas and dust related phenomena. He will use these phenomena and their common cause to show that the earthquakes were caused the rapid migration and expansion of highly compressed and

A novel truncating mutation in FLNA causes periventricular nodular heterotopia, Ehlers-Danlos-like collagenopathy and macrothrombocytopenia.

Science.gov (United States)

Ieda, Daisuke; Hori, Ikumi; Nakamura, Yuji; Ohshita, Hironori; Negishi, Yutaka; Shinohara, Tsutomu; Hattori, Ayako; Kato, Takenori; Inukai, Sachiko; Kitamura, Katsumasa; Kawai, Tomoki; Ohara, Osamu; Kunishima, Shinji; Saitoh, Shinji

2018-06-01

Filamin A (FLNA) is located in Xq28, and encodes the actin binding protein, filamin A. A mutation in FLNA is the most common cause of periventricular nodular heterotopia (PVNH), but a clear phenotype-genotype correlation has not been established. Indeed, some patients with a FLNA mutation have recently been shown to additionally have Ehlers-Danlos-like collagenopathy or macrothrombocytopenia. In an attempt to establish a clearer correlation between clinical symptoms and genotype, we have investigated a phenotype that involves thrombocytopenia in a patient with a truncation of the FLNA gene. We present the case of a 4-year-old girl who, at birth, showed a ventral hernia. At 2 months of age, she was diagnosed with patent ductus arteriosus (PDA) and aortic valve regurgitation. At 11 months, she underwent ligation of the PDA. She was also diagnosed with diaphragmatic eventration by a preoperative test. At 19 months, motor developmental delay was noted, and brain MRI revealed bilateral PVNH with mega cisterna magna. Presently, there is no evidence of epilepsy, intellectual disability or motor developmental delay. She has chronic, mild thrombocytopenia, and a platelet count that transiently decreases after viral infection. Dilation of the ascending aorta is progressing gradually. Genetic testing revealed a de novo nonsense heterozygous mutation in FLNA (NM_001456.3: c.1621G > T; p.Glu541Ter). Immunofluorescence staining of a peripheral blood smear showed a lack of filamin A expression in 21.1% of her platelets. These filamin A-negative platelets were slightly larger than her normal platelets. Our data suggests immunofluorescence staining of peripheral blood smears is a convenient diagnostic approach to identify patients with a FLNA mutation, which will facilitate further investigation of the correlation between FLNA mutations and patient phenotype. Copyright © 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

The MEGA BORG: The value of cooperative damage assessment to trustees, PRPs, and the environment

International Nuclear Information System (INIS)

Helton, D.

1993-01-01

The Natural Resource Damage Assessment (NRDA) process provides natural resource trustees with a method for restoring publicly owned or managed natural resources and their services that are injured as a result of an oil or chemical release. The NRDA process is simple in concept, but provides significant challenges for natural resource trustees. Although the impacts of marine pollution have been studied for many years, the quantification, economic evaluation, and restoration of these impacts brings up controversial scientific, legal, and economic issues. The 1990 MEGA BORG spill in the Gulf of Mexico is an example of a cooperative assessment. Within a few days of the spill, the Texas Water Commission and the National Oceanic and Atmospheric Administration (NOAA) reached and agreement with the owners of the MEGA BORG under which the owners would fund a preliminary assessment of the environmental impact of the spill. Five projects were funded to determine whether there was sufficient injury to justify the completion of a natural resource damage assessment. The MEGA BORG provides an example of a cooperative and scientifically balanced approach to the initiation of damage assessment activities and illustrates the benefits of a cooperative assessment

Incidência da cardiopatia chagásica em 15.000 necrópsias consecutivas e sua associação com os «megas»

Directory of Open Access Journals (Sweden)

A. J. A. Barbosa

1970-08-01

Full Text Available Os AA. estudaram, a incidência da cardiopatia chagásica em 15.000 necrópsias consecutivas e sua associação com os megas. Em 875 cardiopatias chagásicas houve 145 casos de megas, ou seja, 16,56%, com predominância do sexo masculino. No branco houve maior incidência (55 de megas do que no mulato (53 e no negro (31 dentre 858 cardiopatias chagásicas. Em 848 cardiopatias chagásicas, 85,78% eram de indivíduos que faleceram entre 21 e 60 anos. O maior número de cardiopatias (120 ou 14,14% e de "megas'' (21 ou 15,78% foi encontrado nos indivíduos entre 36 a 40 anos. Os nossos resultados mostram uma incidência diferente da associação cardiopatia-mega, em comparação da observada em outras regiões do País e em outros países da América do Sul.

The Uruguayan Per mic mega flora. A synthesis

International Nuclear Information System (INIS)

Cornaglia, L.; Ruiz, F.; Introcaso, A.

2007-01-01

The Permian mega floras of Uruguay. A synthesis. An analysis of the impression and fossil wood floras from the Permian of Uruguay is given through a series of Tables. These show : (1) the list of taxa, (2) anatomical characters of the woods, (3) data on the micro floral associations, (4) paleoenvironmental information and (5) comparisons with contemporaneous Gondwana floras. The evolutionary degree of the woods is briefly analyzed where they correspond to the so-called transition xilotaphofloras as they present typical Paleozoic anatomical characters but with secondary xylem of more advanced characteristics. (author)

Air-quality measurements in mega-cities: Focus on gaseous organic and particulate pollutants and comparison between two contrasted cities, Paris and Beijing

International Nuclear Information System (INIS)

Gros, V.; Sciare, J.; Yu, T.

2007-01-01

The rapid and important development of large urban areas ('mega-cities'), especially in developing countries, causes and will cause serious air-quality problems. Pollutant measurements in these cities help to characterize the chemical nature and the quantity of these pollutants and to constrain air-quality models. This paper focuses on measurements of volatile organic compounds and aerosols that have an important impact on air quality. We present a brief review on existing measurements and experimental strategies in mega-cities and then we show results from recent measurement campaigns that took place in two contrasted mega-cities: Paris and Beijing. (authors)

How to make mega-cities energy efficient?

Energy Technology Data Exchange (ETDEWEB)

Aoki, Hitoshi; Aoki, Yoshitaka

2010-09-15

Tokyo is a Megalopolis with 40 million+ population. It has an energy efficient profile due to its uniqueness as extensive mass rail transit networks, high density and compact urban formation, compact space oriented life style. The other feature is extensive use of electric heat pumps (EHP), which entails low carbon city profile. Further possibility is prepared with water thermal energy utilization, which is widely available also through EHP particularly in Tokyo central districts, which could make Tokyo one of the lowest carbon cities in the world. Emerging mega-cities are expected to learn from Tokyo's success and not from western conventional models.

The Fluid Dynamical Performance of the Carpentier-Edwards PERIMOUNT Magna Ease Prosthesis

Directory of Open Access Journals (Sweden)

Philipp Marx

2018-01-01

Full Text Available The aim of the present in vitro study was the evaluation of the fluid dynamical performance of the Carpentier-Edwards PERIMOUNT Magna Ease depending on the prosthetic size (21, 23, and 25 mm and the cardiac output (3.6–6.4 L/min. A self-constructed flow channel in combination with particle image velocimetry (PIV enabled precise results with high reproducibility, focus on maximal and local peek velocities, strain, and velocity gradients. These flow parameters allow insights into the generation of forces that act on blood cells and the aortic wall. The results showed that the 21 and 23 mm valves have a quite similar performance. Maximal velocities were 3.03±0.1 and 2.87±0.13 m/s; maximal strain Exx, 913.81±173.25 and 896.15±88.16 1/s; maximal velocity gradient Eyx, 1203.14±221.84 1/s and 1200.81±61.83 1/s. The 25 mm size revealed significantly lower values: maximal velocity, 2.47±0.15 m/s; maximal strain Exx, 592.98±155.80 1/s; maximal velocity gradient Eyx, 823.71±38.64 1/s. In summary, the 25 mm Magna Ease was able to create a wider, more homogenous flow with lower peak velocities especially for higher flow rates. Despite the wider flow, the velocity values close to the aortic walls did not exceed the level of the smaller valves.

Gene transcription in Daphnia magna: effects of acute exposure to a carbamate insecticide and an acetanilide herbicide.

Science.gov (United States)

Pereira, Joana Luísa; Hill, Christopher J; Sibly, Richard M; Bolshakov, Viacheslav N; Gonçalves, Fernando; Heckmann, Lars-Henrik; Callaghan, Amanda

2010-05-05

Daphnia magna is a key invertebrate in the freshwater environment and is used widely as a model in ecotoxicological measurements and risk assessment. Understanding the genomic responses of D. magna to chemical challenges will be of value to regulatory authorities worldwide. Here we exposed D. magna to the insecticide methomyl and the herbicide propanil to compare phenotypic effects with changes in mRNA expression levels. Both pesticides are found in drainage ditches and surface water bodies standing adjacent to crops. Methomyl, a carbamate insecticide widely used in agriculture, inhibits acetylcholinesterase, a key enzyme in nerve transmission. Propanil, an acetanilide herbicide, is used to control grass and broad-leaf weeds. The phenotypic effects of single doses of each chemical were evaluated using a standard immobilisation assay. Immobilisation was linked to global mRNA expression levels using the previously estimated 48h-EC(1)s, followed by hybridization to a cDNA microarray with more than 13,000 redundant cDNA clones representing >5000 unique genes. Following exposure to methomyl and propanil, differential expression was found for 624 and 551 cDNAs, respectively (one-way ANOVA with Bonferroni correction, P

Sequence Conservation and Sexually Dimorphic Expression of the Ftz-F1 Gene in the Crustacean Daphnia magna.

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Nur Syafiqah Mohamad Ishak

Full Text Available Identifying the genes required for environmental sex determination is important for understanding the evolution of diverse sex determination mechanisms in animals. Orthologs of Drosophila orphan receptor Fushi tarazu factor-1 (Ftz-F1 are known to function in genetic sex determination. In contrast, their roles in environmental sex determination remain unknown. In this study, we have cloned and characterized the Ftz-F1 ortholog in the branchiopod crustacean Daphnia magna, which produces males in response to environmental stimuli. Similar to that observed in Drosophila, D. magna Ftz-F1 (DapmaFtz-F1 produces two splicing variants, αFtz-F1 and βFtz-F1, which encode 699 and 777 amino acids, respectively. Both isoforms share a DNA-binding domain, a ligand-binding domain, and an AF-2 activation domain and differ only at the A/B domain. The phylogenetic position and genomic structure of DapmaFtz-F1 suggested that this gene has diverged from an ancestral gene common to branchiopod crustacean and insect Ftz-F1 genes. qRT-PCR showed that at the one cell and gastrulation stages, both DapmaFtz-F1 isoforms are two-fold more abundant in males than in females. In addition, in later stages, their sexual dimorphic expressions were maintained in spite of reduced expression. Time-lapse imaging of DapmaFtz-F1 RNAi embryos was performed in H2B-GFP expressing transgenic Daphnia, demonstrating that development of the RNAi embryos slowed down after the gastrulation stage and stopped at 30-48 h after ovulation. DapmaFtz-F1 shows high homology to insect Ftz-F1 orthologs based on its amino acid sequence and exon-intron organization. The sexually dimorphic expression of DapmaFtz-F1 suggests that it plays a role in environmental sex determination of D. magna.

Studies of MicroMegas Chamber for the New Small Wheel using Cosmic Muons

CERN Document Server

Klapdor-kleingrothaus, Thorwald; The ATLAS collaboration

2016-01-01

Micromesh Gaseous (MicroMegas) Detectors will be implemented in the ATLAS detector in the framework of the New Small Wheel Upgrade during the long shut down II in 2019/20. These detectors are used for position measurement and have a high spatial resolution of 100$\\mu$m. In parallel to the ongoing constructions of the later modules, additional performance studies with small MicroMegas prototypes of a size of 10 $\\times$ 10 cm$^2$ are performed. The studies include a cosmic muon test stand in combination with a scalable readout system, such that the influences of variations in the pressure of the operation gas or changes in the humidity at the lower ppm level to the detector performance are investigated. These parameters will impact the later design of detector slow control system at the New Small Wheel in ATLAS.

To flee or not to flee: detection, avoidance and attraction of profitable resources by Daphnia magna studied with olfactometer

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Johann P. Müller

2013-10-01

Full Text Available The cladoceran herbivore Daphnia magna is a major consumer of phytoplankton in lakes. Therefore, this organism may control the phytoplankton community and the proliferation of some algae or cyanobacteria. Cladoceran behaviour and migration in relation to temperature, light or presence of planktivorous fishes have been well studied. In particular, it is known that the detection of kairomones produced by predators may induce avoidance. Avoidance could also occur with other semiochemicals such as cyanotoxins. In order to explore this hypothesis, we used an olfactometer to observe and measure the exploratory behaviour of D. magna individuals based on the motivation for food. Daphnids were allowed to choose between different compounds: water, a pure cyanotoxin, i.e. the microcystin-RR [(MC-RR], extracts of one MC-producing strain (PMC 75.02 and one MC-free strain (PMC 87.02 of Planktothrix agardhii, or a green algae Scenedesmus obliquus. With this experimental design, we observed that i cladocerans are able to detect resources with different qualities, ii they can explore before exhibiting preferences, and iii daphnids are able to avoid compounds that are potentially toxic (e.g., microcystins. First, daphnids explored the environment, subsequently (after about 1.5 h, they showed a significant tendency to stay where there is a profitable resource such as S. obliquus. These results also suggest that specimens of D. magna cannot detect MC compounds from P. agardhii, but they respond to it as a food resource. The study of zooplankton ability to explore the environment when exposed to semiochemicals needs further investigation. 

Selected endocrine disrupting compounds (vinclozolin, flutamide, ketoconazole and dicofol): effects on survival, occurrence of males, growth, molting and reproduction of Daphnia magna.

Science.gov (United States)

Haeba, Maher H; Hilscherová, Klára; Mazurová, Edita; Bláha, Ludek

2008-05-01

Pollution-induced endocrine disruption in vertebrates and invertebrates is a worldwide environmental problem, but relatively little is known about effects of endocrine disrupting compounds (EDCs) in planktonic crustaceans (including Daphnia magna). Aims of the present study were to investigate acute 48 h toxicity and sub-chronic (4-6 days) and chronic (21 days) effects of selected EDCs in D. magna. We have investigated both traditional endpoints as well as other parameters such as sex determination, maturation, molting or embryogenesis in order to evaluate the sensitivity and possible use of these endpoints in ecological risk assessment. We have studied effects of four model EDCs (vinclozolin, flutamide, ketoconazole and dicofol) on D. magna using (i) an acute 48 h immobilization assay, (ii) a sub-chronic, 4-6 day assay evaluating development and the sex ratio of neonates, and (iii) a chronic, 21 day assay studying number of neonates, sex of neonates, molting frequency, day of maturation and the growth of maternal organisms. Acute EC50 values in the 48 h immobilization test were as follows (mg/L): dicofol 0.2, ketoconazole 1.5, flutamide 2.7, vinclozolin >3. Short-term, 4-6 day assays with sublethal concentrations showed that the sex ratio in Daphnia was modulated by vinclozolin (decreased number of neonate males at 1 mg/L) and dicofol (increase in males at 0.1 mg/L). Flutamide (up to 1 mg/L) had no effect on the sex of neonates, but inhibited embryonic development at certain stages during chronic assay, resulting in abortions. Ketoconazole had no significant effects on the studied processes up to 1 mg/L. Sex ratio modulations by some chemicals (vinclozolin and dicofol) corresponded to the known action of these compounds in vertebrates (i.e. anti-androgenicity and anti-oestrogenicity, respectively). Our study revealed that some chemicals known to affect steroid-regulated processes in vertebrates can also affect sublethal endpoints (e.g. embryonic sex determination

Agricultural net primary production in relation to that liberated by the extinction of Pleistocene mega-herbivores: an estimate of agricultural carrying capacity?

Energy Technology Data Exchange (ETDEWEB)

Doughty, Christopher E; Field, Christopher B, E-mail: chris.doughty@ouce.ox.ac.uk, E-mail: cfield@ciw.edu [Department of Global Ecology, Carnegie Institution, Stanford, CA 94305 (United States)

2010-10-15

Mega-fauna (defined as animals > 44 kg) experienced a global extinction with 97 of 150 genera going extinct by {approx} 10 000 years ago. We estimate the net primary production (NPP) that was liberated following the global extinction of these mega-herbivores. We then explore how humans, through agriculture, gradually appropriated this liberated NPP, with specific calculations for 800, 1850, and 2000 AD. By 1850, most of the liberated NPP had been appropriated by people, but NPP was still available in the Western US, South America and Australia. NPP liberated following the extinction of the mega-herbivores was {approx} 2.5% ({approx}1.4 (between 1.2 and 1.6) Pg yr{sup -1} of 56 Pg C yr{sup -1}; Pg: petagrams) of global terrestrial NPP. Liberated NPP peaked during the onset of agriculture and was sufficient for sustaining human agriculture until {approx} 320 (250-500) years ago. Humans currently use {approx} 6 times more NPP than was utilized by the extinct Pleistocene mega-herbivores.

Agricultural net primary production in relation to that liberated by the extinction of Pleistocene mega-herbivores: an estimate of agricultural carrying capacity?

International Nuclear Information System (INIS)

Doughty, Christopher E; Field, Christopher B

2010-01-01

Mega-fauna (defined as animals > 44 kg) experienced a global extinction with 97 of 150 genera going extinct by ∼ 10 000 years ago. We estimate the net primary production (NPP) that was liberated following the global extinction of these mega-herbivores. We then explore how humans, through agriculture, gradually appropriated this liberated NPP, with specific calculations for 800, 1850, and 2000 AD. By 1850, most of the liberated NPP had been appropriated by people, but NPP was still available in the Western US, South America and Australia. NPP liberated following the extinction of the mega-herbivores was ∼ 2.5% (∼1.4 (between 1.2 and 1.6) Pg yr -1 of 56 Pg C yr -1 ; Pg: petagrams) of global terrestrial NPP. Liberated NPP peaked during the onset of agriculture and was sufficient for sustaining human agriculture until ∼ 320 (250-500) years ago. Humans currently use ∼ 6 times more NPP than was utilized by the extinct Pleistocene mega-herbivores.

OER on the Asian Mega Universities: Developments, Motives, Openness, and Sustainability

Science.gov (United States)

Farisi, Mohammad Imam

2013-01-01

The OER movement originated and integrated into ODE developments. Mega Universities (MUs) are among the most important of ODE providers worldwide should be to be the primary organizations for providing access to OER. So far, however, in-depth studies on OER developments in the Asian MUs were very limited. This study focuses on the developments,…

Genomic integration and germline transmission of plasmid injected into crustacean Daphnia magna eggs.

Directory of Open Access Journals (Sweden)

Yasuhiko Kato

Full Text Available The water flea, Daphnia, has been the subject of study in ecology, evolution, and environmental sciences for decades. Over the last few years, expressed sequence tags and a genome sequence have been determined. In addition, functional approaches of overexpression and gene silencing based on microinjection of RNAs into eggs have been established. However, the transient nature of these approaches prevents us from analyzing gene functions in later stages of development. To overcome this limitation, transgenesis would become a key tool. Here we report establishment of a transgenic line using microinjection of plasmid into Daphnia magna eggs. The green fluorescent protein (GFP gene fused with the D. magna histone H2B gene under the control of a promoter/enhancer region of the elongation factor 1α-1 (EF1α-1 gene, EF1α-1::H2B-GFP, was used as a reporter providing high resolution visualization of active chromatin. Transgenic lines were obtained from 0.67% of the total fertile adults that survived the injections. One of the transgenic animals, which exhibited fluorescence in the nuclei of cells during embryogenesis and oogenesis, had two copies of EF1α-1::H2B-GFP in a head-to-tail array. This is the first report of a transgenesis technique in Daphnia and, together with emerging genome sequences, will be useful for advancing knowledge of the molecular biology of Daphnia.

The Principle Of Justice In Magna Carta Libertatum And Its Influence On The Law In General

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Zendeli Emine

2015-12-01

Full Text Available This article aims to expound the principle of justice, as a fundamental value and as an immanent category of law, as well as one of the fundamental human rights, prescribed and guaranteed by a myriad of international instruments and documents. After a brief historical account, by focusing on Article 40 of the Magna Carta Libertatum, which states that: “To No One Will we Sell, To No One Will we refuse or delay, right or justice”, this article claims to show the importance of incorporation of this principle in the provisions of the Magna Carta and its impact on the development of theory and legislation in the past and present. Moreover, the article intends to explore the extent of influence that the priciple of justice has on the functioning of the law in general. Since justice implicates the permanent and constant will to render each person his due, and this achieved through equality, it results that justice means being equal. In this context, the article will explore the concept of equality as a precondition of justice, as well as the conditions and modalities for its implementation.

Effect of carbaryl (carbamate insecticide) on acetylcholinesterase activity of two strains of Daphnia magna (Crustacea, Cladocera).

Science.gov (United States)

Toumi, Hela; Bejaoui, Mustapha; Touaylia, Samir; Burga Perez, Karen F; Ferard, Jean François

2016-11-01

The present study was designed to investigate the effect of carbaryl (carbamate insecticide) on the acetylcholinesterase activity in two strains (same clone A) of the crustacean cladoceran Daphnia magna. Four carbaryl concentrations (0.4, 0.9, 1.8 and 3.7 µg L(-1)) were compared against control AChE activity. Our results showed that after 48 h of carbaryl exposure, all treatments induced a significant decrease of AChE activities whatever the two considered strains. However, different responses were registered in terms of lowest observed effect concentrations (LOEC: 0.4 µg L(-1) for strain 1 and 0.9 µg L(-1) for strains 2) revealing differences in sensitivity among the two tested strains of D. magna. These results suggest that after carbaryl exposure, the AChE activity responses can be also used as a biomarker of susceptibility. Moreover, our results show that strain1 is less sensitive than strain 2 in terms of IC50-48 h of AChE activity. Comparing the EC50-48 h of standard ecotoxicity test and IC50-48 h of AChE inhibition, there is the same order of sensitivity with both strains.

Deep-Sea Mega-Epibenthic Assemblages from the SW Portuguese Margin (NE Atlantic Subjected to Bottom-Trawling Fisheries

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Sofia P. Ramalho

2017-11-01

Full Text Available Bottom-trawling fisheries are a common threat to the health of continental margins worldwide. Together with numerous environmental and biological processes, physical disturbance induced by trawlers can largely shape the benthic habitats and their associated assemblages. At the SW Portuguese Margin, crustacean bottom trawlers have exploited deep-sea habitats for a few decades, but its effects on the benthic biodiversity are practically unknown. During the spring-summer of 2013 and 2014, several Remotely Operated Vehicle (ROV video transects were used to investigate mega-epibenthic abundance, composition, and diversity in soft-sediment areas subjected to varying trawling pressures off Sines and Setúbal (200–800 m. Differences in mega-epibenthic assemblages were linked with environmental changes (depth, grain size, primary productivity and trawling disturbance. The effect of trawling was assessed between segments with similar habitat characteristics, i.e., muddy-sand bottoms between 300 and 500 m. Areas subjected to intensive trawling pressure showed a generally flattened seabed, with abundant recent trawl marks (up to 3 scars.100 m−1, indicating that the seabed physical integrity was compromised. Significant negative correlations were detected between various mega-epibenthic diversity indices [S, H′, and ET(20] and trawling pressure (h.cell−1.y−1. Furthermore, the distinct mega-epibenthic assemblages and absence of several sessile erect morphospecies at both low and highly disturbed locations by trawling off Sines, namely all seapen morphospecies found in non-trawled areas, demonstrates the negative influence of trawling fisheries on the benthic component of the study area. Also, low dissimilarity between assemblages from the main fishing grounds and the adjacent low-disturbance locations, suggests that the potentially negative influence of trawling can extend beyond the targeted areas (e.g., by the plumes of re-suspended sediments. The

Handling technology of Mega-Watt millimeter-waves for optimized heating of fusion plasmas

NARCIS (Netherlands)

Shimozuma, T.; Kubo, S.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Takita, Y.; Kobayashi, S.; Ito, S.; Mizuno, Y.; Idei, H.; Notake, T.; Shapiro, M.A.; Temkin, R.J.; Felici, F.; Goodman, T.P.; Sauter, O.; Minami, R.; Kariya, T.; Imai, T.; Mutoh, T.

2009-01-01

Millimeter-wave components were re-examined for high power (Mega-Watt) and steady-state (greater than one hour) operation. Some millimeter-wave components, including waveguide joints, vacuum pumping sections, power monitors, sliding waveguides, and injection windows, have been improved for high

The evolution of the atlantic mega-undation : Causing the American continental drift

NARCIS (Netherlands)

Bemmelen, R.W. van

Mega-undations are the largest class of deformations of the earth's surface, with diameters of many thousands of kilometers. They result from deepseated mass-circuits, probably in the inner mantle. Though their potential amplitude may be in the order of 100 km, their actual height is not more than

Aspectos raciais dos "megas" e da cardiopatia na doença de Chagas crônica

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Lineu José Miziara

1981-06-01

Full Text Available O estudo de 724 pacientes chagásicos crônicos mostrou que a insuficiência cardíaca congestiva é mais freqüente e de aparecimento mais precoce nos pacientes de raça negra do que nos brancos. A ocorrência de "megas" foi ligeiramente inferior nos chagásicos negros não sendo estatisticamente significativa a diferença observada. A maior freqüência de insuficiência cardíaca nos pretos parece estar relacionada a características biológicas do tecido conjuntivo que condicionam uma resposta fibrosante mais acentuada no miocârdio agredido pela Tripanossomose. Estas observações estariam de acordo com outros estudos sobre a doença de Chagas que admitem ser a denervação o fator mais importante para o aparecimento dos "megas" e a inflamação com fibrose miocârdica acentuada um elemento básico para explicar a insuficiência cardíaca.The study of 724 patients with chronic chagas's disease showed that the cardiac faiture is more frequent and appears earlier in negroes patients when compared to white patients. The occurrence of "megas" was slightly lover in the negroes but the difference was not statisticaiiy significant. The higher frequency of cardiac faiture in the negrões seems to be caused by biological characteristics of the conective tissue which respond to trypanossomiasis with a more severe degree of fibrosis. These findings agree with other reports on Chagas's disease in which it is admitted that the "megas" are chiefly the result of dennervation and cardiac faiture is principally caused by infiammation with myocardial fibrosis.

Classification of solid industrial waste based on ecotoxicology tests using Daphnia magna: an alternative

OpenAIRE

William Gerson Matias; Vanessa Guimarães Machado; Cátia Regina Silva de Carvalho-Pinto; Débora Monteiro Brentano; Letícia Flohr

2005-01-01

The adequate treatment and final disposal of solid industrial wastes depends on their classification into class I or II. This classification is proposed by NBR 10.004; however, it is complex and time-consuming. With a view to facilitating this classification, the use of assays with Daphnia magna is proposed. These assays make possible the identification of toxic chemicals in the leach, which denotes the presence of one of the characteristics described by NBR 10.004, the toxicity, which is a s...

Authority, Legitimacy, and Fragmentation in the (Envisaged) Dispute Settlement Disciplines in Mega-Regionals

NARCIS (Netherlands)

Schill, S.W.; Griller, S.; Obwexer, W.; Vranes, E.

2017-01-01

This chapter analyses the inter-state and investor-state dispute settlement disciplines included in mega-regionals, focusing on the Comprehensive Economic and Trade Agreement and the Trans-Pacific Partnership. It argues that dispute settlement assumes a pivotal role in trade and investment

Daphnia magna shows reduced infection upon secondary exposure to a pathogen.

Science.gov (United States)

McTaggart, Seanna J; Wilson, Philip J; Little, Tom J

2012-12-23

Previous pathogen exposure is an important predictor of the probability of becoming infected. This is deeply understood for vertebrate hosts, and increasingly so for invertebrate hosts. Here, we test if an initial pathogen exposure changes the infection outcome to a secondary pathogen exposure in the natural host-pathogen system Daphnia magna and Pasteuria ramosa. Hosts were initially exposed to an infective pathogen strain, a non-infective pathogen strain or a control. The same hosts underwent a second exposure, this time to an infective pathogen strain, either immediately after the initial encounter or 48 h later. We observed that an initial encounter with a pathogen always conferred protection against infection compared with controls.

Urban adaptation to mega-drought: Anticipatory water modeling, policy, and planning in Phoenix

Science.gov (United States)

Gober, P.; Sampson, D. A.; Quay, R.; White, D. D.; Chow, W.

2016-12-01

There is increasing interest in using the results of water models for long-term planning and policy analysis. Achieving this goal requires more effective integration of human dimensions into water modeling and a paradigm shift in the way models are developed and used. A user-defined focus argues in favor of models that are designed to foster public debate and engagement about the difficult trade-offs that are inevitable in managing complex water systems. These models also emphasize decision making under uncertainty and anticipatory planning, and are developed through a collaborative and iterative process. This paper demonstrates the use of anticipatory modeling for long-term drought planning in Phoenix, one of the largest and fastest growing urban areas in the southwestern USA. WaterSim 5, an anticipatory water policy and planning model, was used to explore groundwater sustainability outcomes for mega-drought conditions across a range of policies, including population growth management, water conservation, water banking, direct reuse of RO reclaimed water, and water augmentation. Results revealed that business-as-usual population growth, per capita use trends, and management strategies may not be sustainable over the long term, even without mega-drought conditions as years of available groundwater supply decline over the simulation period from 2000 to 2060. Adding mega-drought increases the decline in aquifer levels and increases the variability in flows and uncertainty about future groundwater supplies. Simulations that combine drought management policies can return the region to sustainable. Results demonstrate the value of long-term planning and policy analysis for anticipating and adapting to environmental change.

Interactive effects of a bacterial parasite and the insecticide carbaryl to life-history and physiology of two Daphnia magna clones differing in carbaryl sensitivity

International Nuclear Information System (INIS)

De Coninck, Dieter I.M.; De Schamphelaere, Karel A.C.; Jansen, Mieke; De Meester, Luc; Janssen, Colin R.

2013-01-01

Highlights: ► Interactive effects between a bacterial parasite and an insecticide in Daphnia magna. ► Two D. magna clones differing strongly in their sensitivity to the insecticide. ► Effects studied on various life-history and physiological endpoints. ► Genetic differences in strength and direction of interaction effects. -- Abstract: Natural and chemical stressors occur simultaneously in the aquatic environment. Their combined effects on biota are usually difficult to predict from their individual effects due to interactions between the different stressors. Several recent studies have suggested that synergistic effects of multiple stressors on organisms may be more common at high compared to low overall levels of stress. In this study, we used a three-way full factorial design to investigate whether interactive effects between a natural stressor, the bacterial parasite Pasteuria ramosa, and a chemical stressor, the insecticide carbaryl, were different between two genetically distinct clones of Daphnia magna that strongly differ in their sensitivity to carbaryl. Interactive effects on various life-history and physiological endpoints were assessed as significant deviations from the reference Independent Action (IA) model, which was implemented by testing the significance of the two-way carbaryl × parasite interaction term in two-way ANOVA's on log-transformed observational data for each clone separately. Interactive effects (and thus significant deviations from IA) were detected in both the carbaryl-sensitive clone (on survival, early reproduction and growth) and in the non-sensitive clone (on growth, electron transport activity and prophenoloxidase activity). No interactions were found for maturation rate, filtration rate, and energy reserve fractions (carbohydrate, protein, lipid). Furthermore, only antagonistic interactions were detected in the non-sensitive clone, while only synergistic interactions were observed in the carbaryl sensitive clone. Our

Interactive effects of a bacterial parasite and the insecticide carbaryl to life-history and physiology of two Daphnia magna clones differing in carbaryl sensitivity

Energy Technology Data Exchange (ETDEWEB)

De Coninck, Dieter I.M., E-mail: Dieter.DeConinck@UGent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium); De Schamphelaere, Karel A.C. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium); Jansen, Mieke; De Meester, Luc [Laboratory of Aquatic Ecology, Evolution and Conservation, University of Leuven, Ch. Deberiotstraat 32, B-3000 Leuven (Belgium); Janssen, Colin R. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium)

2013-04-15

Highlights: ► Interactive effects between a bacterial parasite and an insecticide in Daphnia magna. ► Two D. magna clones differing strongly in their sensitivity to the insecticide. ► Effects studied on various life-history and physiological endpoints. ► Genetic differences in strength and direction of interaction effects. -- Abstract: Natural and chemical stressors occur simultaneously in the aquatic environment. Their combined effects on biota are usually difficult to predict from their individual effects due to interactions between the different stressors. Several recent studies have suggested that synergistic effects of multiple stressors on organisms may be more common at high compared to low overall levels of stress. In this study, we used a three-way full factorial design to investigate whether interactive effects between a natural stressor, the bacterial parasite Pasteuria ramosa, and a chemical stressor, the insecticide carbaryl, were different between two genetically distinct clones of Daphnia magna that strongly differ in their sensitivity to carbaryl. Interactive effects on various life-history and physiological endpoints were assessed as significant deviations from the reference Independent Action (IA) model, which was implemented by testing the significance of the two-way carbaryl × parasite interaction term in two-way ANOVA's on log-transformed observational data for each clone separately. Interactive effects (and thus significant deviations from IA) were detected in both the carbaryl-sensitive clone (on survival, early reproduction and growth) and in the non-sensitive clone (on growth, electron transport activity and prophenoloxidase activity). No interactions were found for maturation rate, filtration rate, and energy reserve fractions (carbohydrate, protein, lipid). Furthermore, only antagonistic interactions were detected in the non-sensitive clone, while only synergistic interactions were observed in the carbaryl sensitive clone. Our

Interactive effects of a bacterial parasite and the insecticide carbaryl to life-history and physiology of two Daphnia magna clones differing in carbaryl sensitivity

Energy Technology Data Exchange (ETDEWEB)

De Coninck, Dieter I.M., E-mail: Dieter.DeConinck@UGent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium); De Schamphelaere, Karel A.C. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium); Jansen, Mieke; De Meester, Luc [Laboratory of Aquatic Ecology, Evolution and Conservation, University of Leuven, Ch. Deberiotstraat 32, B-3000 Leuven (Belgium); Janssen, Colin R. [Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium)

2013-04-15

Highlights: ► Interactive effects between a bacterial parasite and an insecticide in Daphnia magna. ► Two D. magna clones differing strongly in their sensitivity to the insecticide. ► Effects studied on various life-history and physiological endpoints. ► Genetic differences in strength and direction of interaction effects. -- Abstract: Natural and chemical stressors occur simultaneously in the aquatic environment. Their combined effects on biota are usually difficult to predict from their individual effects due to interactions between the different stressors. Several recent studies have suggested that synergistic effects of multiple stressors on organisms may be more common at high compared to low overall levels of stress. In this study, we used a three-way full factorial design to investigate whether interactive effects between a natural stressor, the bacterial parasite Pasteuria ramosa, and a chemical stressor, the insecticide carbaryl, were different between two genetically distinct clones of Daphnia magna that strongly differ in their sensitivity to carbaryl. Interactive effects on various life-history and physiological endpoints were assessed as significant deviations from the reference Independent Action (IA) model, which was implemented by testing the significance of the two-way carbaryl × parasite interaction term in two-way ANOVA's on log-transformed observational data for each clone separately. Interactive effects (and thus significant deviations from IA) were detected in both the carbaryl-sensitive clone (on survival, early reproduction and growth) and in the non-sensitive clone (on growth, electron transport activity and prophenoloxidase activity). No interactions were found for maturation rate, filtration rate, and energy reserve fractions (carbohydrate, protein, lipid). Furthermore, only antagonistic interactions were detected in the non-sensitive clone, while only synergistic interactions were observed in the carbaryl sensitive clone

The effect of cisterna chyli ablation combined with thoracic duct ligation on abdominal lymphatic drainage.

Science.gov (United States)

Sicard, Gretchen K; Waller, Ken R; McAnulty, Jonathan F

2005-01-01

To evaluate the effect of cisterna chyli ablation (CCA) and thoracic duct ligation (TDL) on abdominal lymphatic drainage in normal dogs. Experimental study. Nine female beagle dogs. TDL was performed in 3 dogs and was combined with CCA (CCA-TDL) and local omentalization in 6 dogs. Contrast lymphangiography was attempted in all dogs immediately before and after TDL. Dogs were reanesthetized at 31-37 days for lymphatic studies by new methylene blue (NMB) injection into a mesenteric lymph node and by contrast lymphangiography. In 6 CCA-TDL dogs, 2 had direct shunting of contrast from the lymphatic system into major abdominal veins, 3 had contrast material that dissipated into abdominal vessels within the mesenteric root, and 1 had shunting into the azygous vein. NMB was not observed within the omental pedicle after CCA-TDL. Chylous drainage was by the azygous vein in all 3 TDL dogs. CCA-TDL disrupted chylous drainage to the thoracic duct and resulted in direct intraabdominal lymphaticovenous anastomoses identified by shunting of lymphatic flow directly into the abdominal vasculature in 5 of 6 CCA-TDL dogs. Omentalization of the cisternal ablation site was not beneficial in augmenting extrathoracic lymphatic drainage and is not recommended with CCA-TDL. CCA-TDL represents a novel approach to surgical redirection of chylous drainage to the venous circulation outside of the thorax and may be useful in the treatment of spontaneous chylothorax in the dog.

The critical importance of defined media conditions in Daphnia magna nanotoxicity studies.

Science.gov (United States)

Römer, Isabella; Gavin, Alex J; White, Thomas A; Merrifield, Ruth C; Chipman, James K; Viant, Mark R; Lead, Jamie R

2013-10-23

Due to the widespread use of silver nanoparticles (AgNPs), the likelihood of them entering the environment has increased and they are known to be potentially toxic. Currently, there is little information on the dynamic changes of AgNPs in ecotoxicity exposure media and how this may affect toxicity. Here, the colloidal stability of three different sizes of citrate-stabilized AgNPs was assessed in standard strength OECD ISO exposure media, and in 2-fold (media2) and 10-fold (media10) dilutions by transmission electron microscopy (TEM) and atomic force microscopy (AFM) and these characteristics were related to their toxicity towards Daphnia magna. Aggregation in undiluted media (media1) was rapid, and after diluting the medium by a factor of 2 or 10, aggregation was reduced, with minimal aggregation over 24h occurring in media10. Acute toxicity measurements were performed using 7nm diameter particles in media1 and media10. In media10 the EC50 of the 7nm particles for D. magna neonates was calculated to be 7.46μgL(-1) with upper and lower 95% confidence intervals of 6.84μgL(-1) and 8.13μgL(-1) respectively. For media1, an EC50 could not be calculated, the lowest observed adverse effect concentration (LOAEC) of 11.25μgL(-1) indicating a significant reduction in toxicity compared to that in media10. The data suggest the increased dispersion of nanoparticles leads to enhanced toxicity, emphasising the importance of appropriate media composition to fully assess nanoparticle toxicity in aquatic ecotoxicity tests. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Filming of zooplankton: a case study of rotifer males and Daphnia magna

Directory of Open Access Journals (Sweden)

Pierluigi Colangeli

2015-11-01

Full Text Available Filming live organisms can give new insights into the hidden life of plankton. Accessibly priced digital cameras are now available for a large range of users. Here, we demonstrate the technical setup and workflow of using a single-lens reflex (DSLR camera to film the behaviour of males of two rotifer species, Brachionus angularis Gosse (1851 and Keratella cochlearis Gosse (1851, and of the cladoceran Daphnia magna Straus (1820. Rotifers are cyclical parthenogens that produce males only under certain environmental conditions. Thus, knowledge on rotifer males is still limited because of their ephemeral nature and because they are often smaller than females. We filmed males of B. angularis and K. cochlearis with a DSLR camera connected to a compound microscope to better understand their morphology and behaviour in comparison to conspecific females. While written descriptions have their scientific value, seeing is complementary because everyone can verify what has been described. We made our videos publicly accessible through links connected to the paper. Our videos are, to our best knowledge, the first on males of B. angularis and K. cochlearis. Furthermore, we filmed the behavioural response of D. magna to ultraviolet (UV radiation with a macro lens attached to the DSLR camera. Approaches like this are valuable tools in environmental teaching. To see live organisms with one’s own eyes may contribute to raising public awareness about the value of water resources and their hidden communities. In summary, filming can be a valuable tool to ignite scientific discussion, but the videos need an open-access platform where they can be referenced in a topic-related order.

Structuring a mega-project

Energy Technology Data Exchange (ETDEWEB)

Kutryk, T. [Husky Oil Operations Ltd., Calgary, AB (Canada)

2004-07-01

This paper presented an overview of mega-project management. Issues concerning scope, cost and schedule were discussed, with reference to the idea that a choice must be made from the outset as to which of the 3 is a main priority. The importance of preparation and the development of a fully resourced plan was emphasized. The use of the parametric 4-D model was discussed. Lessons that the construction industry may learn from manufacturers were presented along with issues of contract development and the role and importance of the project manager. Issues concerning performance measurement were reviewed, including lagging indicators. Project division factors were also discussed, with reference to data lags, naturally concurrent processes and over the fence units. A case study of Walmart was presented. Project design packages and long lead time items were discussed, as were issues concerning human resources. Functional units were examined in relation to zones of influence and unit integration. Various combinations of zones of influence were presented. Issues concerning span of control and varying relationships within a project were discussed. It was emphasized that great deeds can be accomplished by attracting the best people. tabs., figs.

Precambrian mega lineaments across the Indian sub-continent - Preliminary evidence from offshore magnetic data

Digital Repository Service at National Institute of Oceanography (India)

Subrahmanyam, V.; Subrahmanyam, A.S.; Murthy, K.S.R.; Murty, G.P.S.; Sarma, K.V.L.N.S.; SuneetaRani, P.; Anuradha, A.

junction/contact between two major geological provinces, viz. the Southern Granulite Terrain (SGT) and the Dharwar Craton. In addition to these two mega lineaments, major faults have been inferred, which acted as controlling parameters to create a bulge...

The antioxidant effect of Green Tea Mega EGCG against electromagnetic radiation-induced oxidative stress in the hippocampus and striatum of rats.

Science.gov (United States)

Ahmed, Nawal A; Radwan, Nasr M; Aboul Ezz, Heba S; Salama, Noha A

2017-01-01

Electromagnetic radiation (EMR) of cellular phones may affect biological systems by increasing free radicals and changing the antioxidant defense systems of tissues, eventually leading to oxidative stress. Green tea has recently attracted significant attention due to its health benefits in a variety of disorders, ranging from cancer to weight loss. Thus, the aim of the present study was to investigate the effect of EMR (frequency 900 MHz modulated at 217 Hz, power density 0.02 mW/cm 2 , SAR 1.245 W/kg) on different oxidative stress parameters in the hippocampus and striatum of adult rats. This study also extends to evaluate the therapeutic effect of green tea mega EGCG on the previous parameters in animals exposed to EMR after and during EMR exposure. The experimental animals were divided into four groups: EMR-exposed animals, animals treated with green tea mega EGCG after 2 months of EMR exposure, animals treated with green tea mega EGCG during EMR exposure and control animals. EMR exposure resulted in oxidative stress in the hippocampus and striatum as evident from the disturbances in oxidant and antioxidant parameters. Co-administration of green tea mega EGCG at the beginning of EMR exposure for 2 and 3 months had more beneficial effect against EMR-induced oxidative stress than oral administration of green tea mega EGCG after 2 months of exposure. This recommends the use of green tea before any stressor to attenuate the state of oxidative stress and stimulate the antioxidant mechanism of the brain.

Quality of life of residents living in a city hosting mega-sport events: a longitudinal study.

Science.gov (United States)

Pfitzner, Rebecca; Koenigstorfer, Joerg

2016-10-21

It remains unknown whether and when the hosting of mega-sport events increases quality of life of host city residents. The aim of this study is to assess the changes in quality of life of host city residents over the course of hosting a mega-sport event until three months after the event, depending on residents' perception of the atmosphere during the event. The study was conducted in Rio de Janeiro, one of the host cities of the 2014 FIFA World Cup in soccer. Participants were recruited from a Brazilian market research agency's panel and surveyed online. The WHOQOL-BREF was used to measure quality of life of residents of Rio de Janeiro (n = 281) in three waves in the context of the 2014 FIFA World Cup. Perceived atmosphere at the event was measured via an established scale. Piecewise latent growth models were used to analyze individual changes in the four domains of quality of life per se and depending on perceived atmosphere. There was no change in quality of life with respect to physical, social, psychological, and environmental health for all participants during the course of the event. However, residents who perceived a positive atmosphere rated the social and environmental domains of quality of life more positively right after the end (vs. at the beginning) of the World Cup. This increase sustained until three months after the event. Physical health (particularly at high levels of perceived atmosphere) and psychological health decreased from right after the event until three months after. There was no positive effect of the hosting of the mega-sport event on the four quality of life domains of the panel members (who were residents of a city hosting a mega-sport event) per se. The individual changes in quality of life vary by perception of atmosphere and by domain of quality of life.

Assessing mandated credit programs: Case study of the Magna Carta in the Philippines

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Ryan Jacildo

2016-09-01

Full Text Available We examine the effects of a mandated credit program to small and medium enterprises in the Philippines (Magna Carta Law using a panel dataset compiled from official data published by the Bangko Sentral ng Pilipinas. The final sample of 109 financial institutions represented over 90% of total finance sector assets in the Philippines. We highlight three important findings. First, although the total lending levels to micro, small, and medium enterprises (MSMEs grew slightly, the percentage shares of loans allocated to MSMEs declined drastically from a peak of 30% of total loans in 2002 to 16.4% in 2010. Second, following the upwards revision of the loan target (from 6% to 8% for smaller firms in 2008, there was a sharp increase in noncompliance especially amongst universal and commercial banks. On the other hand, total loans to medium enterprises were still more than threefold larger than the targeted 2%. Third, there is an increased heterogeneity in optimal loan portfolio across banks. Most surprisingly, the absolute level of MSME lending by rural and cooperative banks declined since 2008. Direct compliance amongst universal and commercial banks decreased beginning in the late 2007, while that of thrift banks increased to almost 100%. Abolishing the Magna Carta targets for medium-sized enterprise loans would most likely yield little adverse effects. Meanwhile, efforts to improve financial access to MSMEs should focus on alternative nondistortionary ways to increase financing supply, such as improving institutional framework for informational availability and development of equity and bond markets for MSMEs.

Selected endocrine disrupting compounds (vinclozolin, flutamide, ketoconazole and dicofol): Effects on survival, occurrence of males, growth, molting and reproduction of Daphnia magna

Czech Academy of Sciences Publication Activity Database

Haeba, M. H.; Hilscherová, Klára; Mazurová, E.; Bláha, Luděk

2008-01-01

Roč. 15, č. 3 (2008), s. 222-227 ISSN 0944-1344 Institutional research plan: CEZ:AV0Z60050516 Keywords : Daphnia magna * dicofol * endocrine disruption Subject RIV: EF - Botanics Impact factor: 2.492, year: 2008

Mimicking Daphnia magna bioassay performance by an electronic tongue for urban water quality control

Energy Technology Data Exchange (ETDEWEB)

Kirsanov, Dmitry, E-mail: d.kirsanov@gmail.com [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Legin, Evgeny [Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Sensor Systems LLC, St. Petersburg (Russian Federation); Zagrebin, Anatoly; Ignatieva, Natalia; Rybakin, Vladimir [Institute of Limnology, Russian Academy of Sciences, St. Petersburg (Russian Federation); Legin, Andrey [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation)

2014-05-01

Highlights: • -Daphnia magna bioassay can be simulated with multisensor system. • Urban water toxicity can be predicted from potentiometric ET data. • Independent test set validation confirms statistical significance of the results. - Abstract: Toxicity is one of the key parameters of water quality in environmental monitoring. However, being evaluated as a response of living beings (as their mobility, fertility, death rate, etc.) to water quality, toxicity can only be assessed with the help of these living beings. This imposes certain restrictions on toxicity bioassay as an analytical method: biotest organisms must be properly bred, fed and kept under strictly regulated conditions and duration of tests can be quite long (up to several days), thus making the whole procedure the prerogative of the limited number of highly specialized laboratories. This report describes an original application of potentiometric multisensor system (electronic tongue) when the set of electrochemical sensors was calibrated against Daphnia magna death rate in order to perform toxicity assessment of urban waters without immediate involvement of living creatures. PRM (partial robust M) and PLS (projections on latent structures) regression models based on the data from this multisensor system allowed for prediction of toxicity of unknown water samples in terms of biotests but in the fast and simple instrumental way. Typical errors of water toxicity predictions were below 20% in terms of Daphnia death rate which can be considered as a good result taking into account the complexity of the task.

Relationships between acute toxicities of para nitrophenol (p-NP) and nitrobenzene (NB) to Daphnia magna and Photobacterium phosphoreum: Physicochemical properties and metabolites under anaerobic/aerobic sequentials

International Nuclear Information System (INIS)

Sponza, Delia Teresa; Kuscu, Ozlem Selcuk

2011-01-01

In this study, the acute toxicities of nitrobenzene (NB) and para nitrophenol (p-NP) were investigated in a high rate sequential anaerobic migrating blanket (AMBR)/aerobic completely stirred tank reactor (CSTR) using Microtox and Daphnia magna tests. After sequential anaerobic and aerobic treatments, the inhibitions in the Microtox bacteria decreased from an initial 78.10-48.20% and 4.00%, respectively, in wastewater containing 40.00 mg/L p-NP. The inhibitions of the influent wastewater containing 60.00 mg/L NB decreased from 72.10% to 45.30% and to 4.00% after anaerobic and aerobic treatment, respectively. The acute toxicity removals were 94% and 93% in the effluent of the whole sequential system, for p-NP and NB, respectively. The acute toxicity in the influent was dependent on the parent NB and p-NP concentrations and ons their physicochemical properties such as hydrophobicity, octanol/water partition coefficient and vapour density for both Microtox bacteria and Daphnia magna while the toxicity in the effluent of the anaerobic reactor was strongly dependent on the metabolites of p-NP (p-amino phenol, phenol, NH 4 -N) and NB (aniline) for Microtox test. This effluent was not toxic to Daphnia magna.

The economic performance of supply chain(s) served by the mega freight transport vehicles

NARCIS (Netherlands)

Janic, M.

2014-01-01

This paper deals with the economic performances of supply chain(s) served by different including the mega freight transport vehicles. These performances are considered as a dimension of the supply chain’s sustainability together with the infrastructural, technical/technological, operational,

Communicating mega-projects in the face of uncertainties: Israeli mass media treatment of the Dead Sea Water Canal.

Science.gov (United States)

Fischhendler, Itay; Cohen-Blankshtain, Galit; Shuali, Yoav; Boykoff, Max

2015-10-01

Given the potential for uncertainties to influence mega-projects, this study examines how mega-projects are deliberated in the public arena. The paper traces the strategies used to promote the Dead Sea Water Canal. Findings show that the Dead Sea mega-project was encumbered by ample uncertainties. Treatment of uncertainties in early coverage was dominated by economics and raised primarily by politicians, while more contemporary media discourses have been dominated by ecological uncertainties voiced by environmental non-governmental organizations. This change in uncertainty type is explained by the changing nature of the project and by shifts in societal values over time. The study also reveals that 'uncertainty reduction' and to a lesser degree, 'project cancellation', are still the strategies most often used to address uncertainties. Statistical analysis indicates that although uncertainties and strategies are significantly correlated, there may be other intervening variables that affect this correlation. This research also therefore contributes to wider and ongoing considerations of uncertainty in the public arena through various media representational practices. © The Author(s) 2013.

Resistance to a bacterial parasite in the crustacean Daphnia magna shows Mendelian segregation with dominance.

Science.gov (United States)

Luijckx, P; Fienberg, H; Duneau, D; Ebert, D

2012-05-01

The influence of host and parasite genetic background on infection outcome is a topic of great interest because of its pertinence to theoretical issues in evolutionary biology. In the present study, we use a classical genetics approach to examine the mode of inheritance of infection outcome in the crustacean Daphnia magna when exposed to the bacterial parasite Pasteuria ramosa. In contrast to previous studies in this system, we use a clone of P. ramosa, not field isolates, which allows for a more definitive interpretation of results. We test parental, F1, F2, backcross and selfed parental clones (total 284 genotypes) for susceptibility against a clone of P. ramosa using two different methods, infection trials and the recently developed attachment test. We find that D. magna clones reliably exhibit either complete resistance or complete susceptibility to P. ramosa clone C1 and that resistance is dominant, and inherited in a pattern consistent with Mendelian segregation of a single-locus with two alleles. The finding of a single host locus controlling susceptibility to P. ramosa suggests that the previously observed genotype-genotype interactions in this system have a simple genetic basis. This has important implications for the outcome of host-parasite co-evolution. Our results add to the growing body of evidence that resistance to parasites in invertebrates is mostly coded by one or few loci with dominance.

The Role of AChE in Swimming Behavior of Daphnia magna: Correlation Analysis of Both Parameters Affected by Deltamethrin and Methomyl Exposure

Directory of Open Access Journals (Sweden)

Qing Ren

2017-01-01

Full Text Available The unpredictable toxicity of insecticides may cause behavior disorder of biological organisms. In order to assess the role of acetylcholinesterase (AChE in swimming behavior of Daphnia magna, a correlation analysis of both parameters in 24 h exposure of deltamethrin (DM and methomyl (MT was investigated. The behavior responses of D. magna in DM (13.36 μg/L and 33.40 μg/L and MT (19.66 μg/L and 49.15 μg/L suggested that recovery behavior in the adjustment phase was crucial, and behavior homeostasis provided them with an optimal way to achieve a wider tolerance against environmental stress. During the experiment, positive effects on AChE activity occurred in the beginning of the exposure. Even though the de novo synthesis of AChE in D. magna might help it recover, the AChE inhibition in different treatments could be observed. Some induction effects on AChE activity at the beginning of exposure occurred, and a 50% decrease may cause toxic effects on behavior. In most treatments, the results showed that both behavior strength and AChE activity stayed in the same field within a correlation circle. These results illustrated that the environmental stress caused by both DM and MT could inhibit AChE activity and subsequently induce a stepwise behavior response, though both pesticides affect it as direct and indirect inhibitors, respectively.

Technology and economic impacts of mega-sports events: A key issue? Exploratory insights from literature

Directory of Open Access Journals (Sweden)

Chanaron Jean Jacques

2014-01-01

Full Text Available Mega-sport events such as Olympic Games or Football World Cup are always presented as providing the hosting nation and/or city with huge benefits. Supporters of such events quote economic, social and cultural impacts for the region as well as contributions to scientific and technological progress and innovation. obviously, they need to politically justify the impressive and growing financial investment required by organizing Olympic Games or World Cup. The article aims at looking at a quite abundant academic literature with the objectives of defining the various potential impacts and the methods used for their assessment. It concludes that there is no universal and scientifically valid model for evaluating the benefits of mega-sport events and that organizers should be very cautious when arguing in favor of deciding to host such events.

Arginine kinase in the cladoceran Daphnia magna: cDNA sequencing and expression is associated with resistance to toxic Microcystis.

Science.gov (United States)

Lyu, Kai; Zhang, Lu; Zhu, Xuexia; Cui, Guilian; Wilson, Alan E; Yang, Zhou

2015-03-01

Nutrient loading derived from anthropogenic activities into lakes have increased the frequency, severity and duration of toxic cyanobacterial blooms around the world. Although herbivorous zooplankton are generally considered to be unable to control toxic cyanobacteria, populations of some zooplankton, including Daphnia, have been shown to locally adapt to toxic cyanobacteria and suppress cyanobacterial bloom formation. However, little is known about the physiology of zooplankton behind this phenomenon. One possible explanation is that some zooplankton may induce more tolerance by elevating energy production, thereby adding more energy allocation to detoxification expenditure. It is assumed that arginine kinase (AK) serves as a core in temporal and spatial adenosine triphosphate (ATP) buffering in cells with high fluctuating energy requirements. To test this hypothesis, we studied the energetic response of a single Daphnia magna clone exposed to a toxic strain of Microcystis aeruginosa, PCC7806. Arginine kinase of D. magna (Dm-AK) was successfully cloned. An ATP-gua PtransN domain which was described as a guanidine substrate specificity domain and an ATP-gua Ptrans domain which was responsible for binding ATP were both identified in the Dm-AK. Phylogenetic analysis of AKs in a range of arthropod taxa suggested that Dm-AK was as dissimilar to other crustaceans as it was to insects. Dm-AK transcript level and ATP content in the presence of M. aeruginosa were significantly lower than those in the control diet containing only the nutritious chlorophyte, Scenedesmus obliquus, whereas the two parameters in the neonates whose mothers had been previously exposed to M. aeruginosa were significantly higher than those of mothers fed with pure S. obliquus. These findings suggest that Dm-AK might play an essential role in the coupling of energy production and utilization and the tolerance of D. magna to toxic cyanobacteria. Copyright © 2014 Elsevier B.V. All rights reserved.

Reducing Prosthesis-Patient Mismatch With Edwards Magna Prosthesis for Aortic Valve Replacement.

Science.gov (United States)

Kume, Yuta; Fujita, Tomoyuki; Fukushima, Satsuki; Hata, Hiroki; Shimahara, Yusuke; Matsumoto, Yorihiko; Yamashita, Kizuku; Kobayashi, Junjiro

2017-03-24

Prosthesis-patient mismatch (PPM) is associated with increased mid-term and long-term mortality rates after aortic valve replacement (AVR). This study aimed to evaluate the efficacy of the Carpentier-Edwards Perimount Magna and Magna Ease (CEPMs) aortic bioprostheses to reduce the incidence of PPM.Methods and Results:Altogether, 282 consecutive patients (113 women, mean age 69.9±9.9 years) underwent AVR with a CEPMs between 2008 and 2015. They were divided into 3 groups based on the risk of PPM as a result of their body surface area and aortic annular diameter (BSA/AnnD ratio): low-risk (LR) group: 0.64±0.05 m 2 /cm (n=94); medium-risk (MR) group: 0.73±0.02 m 2 /cm (n=94); high-risk (HR) group: 0.83±0.05 m 2 /cm (n=94). The 30-day mortality rate was 0.4%. The 5-year actuarial survival rates were 93.2%, 92.3%, and 94.8% for groups LR, MR, and HR, respectively. No explants as a result of structural valve deterioration occurred. No patients showed severe PPM, defined as a measured effective orifice area index (EOAI) <0.65 cm 2 /m 2 . Although there were significant (P<0.05) differences in EOAI (0.98±0.2, 0.90±0.21, and 0.88±0.1 cm 2 /m 2 among the LR, MR, and HR groups, respectively), the corresponding transvalvular mean pressure gradients (13.0±5.5, 12.3±4.0, 12.7±5.3 mmHg) and regression rates of the left ventricular mass (29.8%, 28.7%, 28.9%) were similar among groups. CEPMs provide low surgical risk and reduce the risks of PPM, even in HR patients, with excellent hemodynamics.

The future of mega sport events : Examining the ‘Dutch Approach’ to legacy planning

NARCIS (Netherlands)

Hartman, S.; Zandberg, T.

2015-01-01

Purpose – Mega sport events (MSE) are immensely popular but also highly criticized because these nclude large public budgets and involve politically sensitive topics. In this context, there is an increasing attention toward legacy planning, the effort to confer long-term benefits to a host

Mega-science accelerator projects in China and their impact on economy

International Nuclear Information System (INIS)

Zhang Chuang

2012-01-01

Along with the rapid development of national economy in China, a number of mega-science projects have been or being constructed. In respect to the large accelerator-based projects, the Beijing Electron-Positron Colliders (BEPC) and its upgrading project BEPCⅡ, the Hefei Light Source (HLS), the Heavy Ion Research Facility in Lanzhou (HIRFL) and its Cooling Storage Rings (HIRFL-CSR) and the Shanghai Synchrotron Radiation Facility (SSRF) were successfully constructed and put into operation. The Beijing Radioactive Ion Facility (BRIF) and the China Spallation Neutron Source (CSNS) are under construction. A particle accelerator is an integration of many HI-tech components. In order to reach the scientific goal of an accelerator project, a great deal new technologies need to be developed during its construction and operation and thus speed up technology development and this will positively impact on the economy. In this paper, the mega-science accelerator projects are briefly described and applications of accelerators in the economy are reviewed. The paper emphasizes spin-off of the accelerator technology developed during R and D and construction of the projects. Approaches of collaboration between academia and industry are discussed. With some examples, the benefits experienced in the laboratory-industry collaboration and approach of its economic compact are illustrated. (author)

Photon pair spectrometers in a μ → eγ decay search with the MEGA experiment

International Nuclear Information System (INIS)

Dzemidzic, M.

1993-01-01

The MEGA experiment at LAMPF is conducting a search for the lepton family number violating decay μ + →e + γ with a branching ratio sensitivity of a few parts in 10 -13 . The detectors are contained in a 1.5 T solenoidal magnetic field. Positrons are confined to the central region and are measured by a set of cylindrical MWPCs. Photons are converted into e + e - pairs by one of three pair spectrometers in the outer region. Each pair spectrometer consists of an inner layer of plastic scintillator, two lead converters separated by a MWPC and three layers of drift chambers. The MEGA collaboration successfully concluded 1992 data taking with a set of positron MWPCs and two pair spectrometers. A brief overview of the pair spectrometer design and performance will be followed by a presentation of results to date of the data analysis

Recent Mega-Thrust Tsunamigenic Earthquakes and PTHA

Science.gov (United States)

Lorito, S.

2013-05-01

The occurrence of several mega-thrust tsunamigenic earthquakes in the last decade, including but not limited to the 2004 Sumatra-Andaman, the 2010 Maule, and 2011 Tohoku earthquakes, has been a dramatic reminder of the limitations in our capability of assessing earthquake and tsunami hazard and risk. However, the increasingly high-quality geophysical observational networks allowed the retrieval of most accurate than ever models of the rupture process of mega-thrust earthquakes, thus paving the way for future improved hazard assessments. Probabilistic Tsunami Hazard Analysis (PTHA) methodology, in particular, is less mature than its seismic counterpart, PSHA. Worldwide recent research efforts of the tsunami science community allowed to start filling this gap, and to define some best practices that are being progressively employed in PTHA for different regions and coasts at threat. In the first part of my talk, I will briefly review some rupture models of recent mega-thrust earthquakes, and highlight some of their surprising features that likely result in bigger error bars associated to PTHA results. More specifically, recent events of unexpected size at a given location, and with unexpected rupture process features, posed first-order open questions which prevent the definition of an heterogeneous rupture probability along a subduction zone, despite of several recent promising results on the subduction zone seismic cycle. In the second part of the talk, I will dig a bit more into a specific ongoing effort for improving PTHA methods, in particular as regards epistemic and aleatory uncertainties determination, and the computational PTHA feasibility when considering the full assumed source variability. Only logic trees are usually explicated in PTHA studies, accounting for different possible assumptions on the source zone properties and behavior. The selection of the earthquakes to be actually modelled is then in general made on a qualitative basis or remains implicit

Photon detector for MEGA. Final report, July 16, 1992--May 31, 1993

International Nuclear Information System (INIS)

Gagliardi, C.A.; Tribble, R.E.

1993-01-01

During the past year, we have continued our work on the photon detector for the MEGA experiment at Los Alamos. The MEGA photon detector is designed to observe the 52.83 MeV photon produced in a π → eγ decay with an energy resolution of 1.25 MeV, a position resolution of 2 x 5 mm 2 , a directional resolution of 10 degree, a time resolution of 500 ps, and an efficiency of about 5.4%. (All quoted resolutions are FWHM.) It consists of three independent concentric cylindrical pair spectrometers mounted within a 1.5 T magnetic field produced by a superconducting solenoid magnet. Each pair spectrometer includes two thin (0.045 radiation lengths each) Pb foils to convert photons into e + e - pairs. The two smaller pair spectrometers have three drift chamber layers to track the e + e - pairs and thereby determine both their locations and their vector momenta. The third pair spectrometer has four layers of drift chamber, together with a larger turning region, to provide better tracking information for high energy photons such as those from the π 0 → 2γ decay

QSTR with extended topochemical atom (ETA) indices. 16. Development of predictive classification and regression models for toxicity of ionic liquids towards Daphnia magna

International Nuclear Information System (INIS)

Roy, Kunal; Das, Rudra Narayan

2013-01-01

Highlights: • Ionic liquids are not intrinsically ‘green chemicals’ and require toxicological assessment. • Predictive QSTR models have been developed for toxicity of ILs to Daphnia magna. • Simple two dimensional descriptors were used to reduce the computational burden. • Discriminant and regression based models showed appreciable predictivity and reproducibility. • The extracted features can be explored in designing novel environmentally-friendly agents. -- Abstract: Ionic liquids have been judged much with respect to their wide applicability than their considerable harmful effects towards the living ecosystem which has been observed in many instances. Hence, toxicological introspection of these chemicals by the development of predictive mathematical models can be of good help. This study presents an attempt to develop predictive classification and regression models correlating the structurally derived chemical information of a group of 62 diverse ionic liquids with their toxicity towards Daphnia magna and their interpretation. We have principally used the extended topochemical atom (ETA) indices along with various topological non-ETA and thermodynamic parameters as independent variables. The developed quantitative models have been subjected to extensive statistical tests employing multiple validation strategies from which acceptable results have been reported. The best models obtained from classification and regression studies captured necessary structural information on lipophilicity, branching pattern, electronegativity and chain length of the cationic substituents for explaining ecotoxicity of ionic liquids towards D. magna. The derived information can be successfully used to design better ionic liquid analogues acquiring the qualities of a true eco-friendly green chemical

Phenoloxidase but not lytic activity reflects resistance against Pasteuria ramosa in Daphnia magna.

Science.gov (United States)

Pauwels, Kevin; De Meester, Luc; Decaestecker, Ellen; Stoks, Robby

2011-02-23

The field of ecological immunology strongly relies on indicators of immunocompetence. Two major indicators in invertebrates, the activity of phenoloxidase (PO) and lytic activity have recently been questioned in studies showing that, across a natural range of baseline levels, these indicators did not predict resistance against a manipulated challenge with natural parasites. We confirmed this finding by showing that baseline levels of PO and lytic activity in the host Daphnia magna were not related to spore load of the parasite Pasteuria ramosa. Yet, PO levels in infected hosts did predict spore load, indicating PO activity can be useful as an indicator of immunocompetence in this model parasite-host system.

Acute and chronic toxicity of buprofezin on Daphnia magna and the recovery evaluation.

Science.gov (United States)

Liu, Yong; Qi, Suzhen; Zhang, Wen; Li, Xuefeng; Qiu, Lihong; Wang, Chengju

2012-11-01

The toxic effects of buprofezin on Daphnia magna after both chronic and acute exposures were evaluated according to OECD guidelines. A 48-h acute exposure of buprofezin resulted in daphnid immobility at an EC(50) of 0.44 mg/L. In a 14 days chronic exposure of buprofezin (0, 0.025, 0.05, 0.10 and 0.15 mg/L), the development and reproduction of daphnids were all significantly affected and the body length was more sensitive than other observed parameters. However, the adverse effects of buprofezin on parental daphnids can be passed on to their offspring and cannot be recovered in a short time.

Mega-pixel PQR laser chips for interconnect, display ITS, and biocell-tweezers OEIC

Science.gov (United States)

Kwon, O'Dae; Yoon, J. H.; Kim, D. K.; Kim, Y. C.; Lee, S. E.; Kim, S. S.

2008-02-01

We describe a photonic quantum ring (PQR) laser device of three dimensional toroidal whispering gallery cavity. We have succeeded in fabricating the first genuine mega-pixel laser chips via regular semiconductor technology. This has been realized since the present injection laser emitting surface-normal dominant 3D whispering gallery modes (WGMs) can be operated CW with extremely low operating currents (μA-nA per pixel), together with the lasing temperature stabilities well above 140 deg C with minimal redshifts, which solves the well-known integration problems facing the conventional VCSEL. Such properties unusual for quantum well lasers become usual because the active region, involving vertically confining DBR structure in addition to the 2D concave WGM geometry, induces a 'photonic quantum ring (PQR)-like' carrier distribution through a photonic quantum corral effect. A few applications of such mega-pixel PQR chips are explained as follows: (A) Next-generation 3D semiconductor technologies demand a strategy on the inter-chip and intra-chip optical interconnect schemes with a key to the high-density emitter array. (B) Due to mounting traffic problems and fatalities ITS technology today is looking for a revolutionary change in the technology. We will thus outline how 'SLEEP-ITS' can emerge with the PQR's position-sensing capability. (C) We describe a recent PQR 'hole' laser of convex WGM: Mega-pixel PQR 'hole' laser chips are even easier to fabricate than PQR 'mesa' lasers. Genuine Laguerre-Gaussian (LG) beam patterns of PQR holes are very promising for biocell manipulations like sorting mouse myeloid leukemia (M1s) cells. (D) Energy saving and 3D speckle-free POR laser can outdo LEDs in view of red GaAs and blue GaN devices fabricated recently.

Cadmium tolerance in seven Daphnia magna clones is associated with reduced hsp70 baseline levels and induction

International Nuclear Information System (INIS)

Haap, Timo; Koehler, Heinz-R.

2009-01-01

The stress protein hsp70 is part of the intracellular alarm and repair system which enables organisms to counteract negative effects of toxicants on protein integrity. Under long-term selection pressure exerted by environmental pollution, in particular heavy metals, this system may be expected to play a major role in the course of local, microevolutionary events leading to the acquisition of toxicant resistance. Seven clones of Daphnia magna from different geographical regions were characterized regarding their sensitivity to Cd, their hsp70 expression, and Cd accumulation. In an acute immobilisation assay, the tested clones showed remarkable differences in their sensitivity to Cd. The highest EC 50 values by far were obtained for the clone displaying lowest hsp70 expression. In general, hsp70 levels reflected the order of sensitivity to Cd among the seven clones reciprocally. Clonal variations in sensitivity and hsp70 expression could not be related to differential accumulation of Cd, though. In summary, the association of stress insensitivity with low hsp70 induction which has been exemplarily reported for populations of different invertebrates under strong selection pressure could be affirmed for a largely parthenogenetic species for the first time. Furthermore, our observation has serious consequences for the interpretation of toxicological assays using a single D. magna clone solely.

Relationships between acute toxicities of para nitrophenol (p-NP) and nitrobenzene (NB) to Daphnia magna and Photobacterium phosphoreum: Physicochemical properties and metabolites under anaerobic/aerobic sequentials

Energy Technology Data Exchange (ETDEWEB)

Sponza, Delia Teresa, E-mail: delya.sponza@deu.edu.tr [Dokuz Eyluel University, Engineering Faculty, Environmental Engineering Department, Buca Kaynaklar Campus, Buca, Izmir (Turkey); Kuscu, Ozlem Selcuk [Department of Environmental Engineering, Engineering and Architecture Faculty, Sueleyman Demirel University, Cuenuer Campus, 32260 Isparta (Turkey)

2011-01-30

In this study, the acute toxicities of nitrobenzene (NB) and para nitrophenol (p-NP) were investigated in a high rate sequential anaerobic migrating blanket (AMBR)/aerobic completely stirred tank reactor (CSTR) using Microtox and Daphnia magna tests. After sequential anaerobic and aerobic treatments, the inhibitions in the Microtox bacteria decreased from an initial 78.10-48.20% and 4.00%, respectively, in wastewater containing 40.00 mg/L p-NP. The inhibitions of the influent wastewater containing 60.00 mg/L NB decreased from 72.10% to 45.30% and to 4.00% after anaerobic and aerobic treatment, respectively. The acute toxicity removals were 94% and 93% in the effluent of the whole sequential system, for p-NP and NB, respectively. The acute toxicity in the influent was dependent on the parent NB and p-NP concentrations and ons their physicochemical properties such as hydrophobicity, octanol/water partition coefficient and vapour density for both Microtox bacteria and Daphnia magna while the toxicity in the effluent of the anaerobic reactor was strongly dependent on the metabolites of p-NP (p-amino phenol, phenol, NH{sub 4}-N) and NB (aniline) for Microtox test. This effluent was not toxic to Daphnia magna.

Evaluation of Baffle Fixes Film up Flow Sludge Blanket Filtration (BFUSBF System in Treatment of Wastewaters from Phenol and 2,4-Dinitrophenol Using Daphnia Magna Bioassay

Directory of Open Access Journals (Sweden)

Mohammad Javad Ghannadzadeh

2016-02-01

Full Text Available Background: Phenol and nitrophenol are common compounds found in different types of industrial wastewater known as serious threats to human health and natural environment. In this study, Daphnia magna was used to evaluate the effectiveness of "baffle fixes film up flow sludge blanket filtration" (BFUSBF system in elimination of phenolic compounds from water. Methods: D. magna cultures were used as toxicity index of phenol and 2,4-DNP mixtures after treatment by a pilot BFUSBF system which consisted of baffle in anoxic section and biofilm in aerobic sections. Initial concentrations were 312 mg/L phenol and 288 mg/L 2,4-dinitrophenol (2,4-DNP. Results: Bioassay tests showed that D. magna was influenced by the toxicity of phenol and 2,4 DNP mixtures. The comparison between the toxicity of initial phenol and 2,4-DNP mixtures and the output toxic unit (TU derived from BFUSBF treatment system showed that the TU of the effluent from BFUSBF reactor was much lower than that of the solution that entered the reactor. Conclusion: Based on the acute toxicity test, BFUSBF process could reduce phenol and 2,4-DNP in aqueous solutions. Therefore, it is possible to use BFUSBF process as an appropriate treatment option for wastewaters containing phenolic compounds.

Ácidos graxos poliinsaturados ômega-3 e ômega-6: importância e ocorrência em alimentos Omega-3 and omega-6 polyunsaturated fatty acids: importance and occurrence in foods

Directory of Open Access Journals (Sweden)

Clayton Antunes Martin

2006-12-01

Full Text Available Os ácidos graxos poliinsaturados abrangem as famílias de ácidos graxos ômega-3 e ômega-6. Os ácidos graxos de cadeia muito longa, como os ácidos araquidônico e docosaexaenóico, desempenham importantes funções no desenvolvimento e funcionamento do cérebro e da retina. Esse grupo de ácidos graxos não pode ser obtido pela síntese de novo, mas pode ser sintetizado a partir dos ácidos linoléico e alfa-linolênico presentes na dieta. Neste artigo são considerados os principais fatores que podem inibir a atividade das enzimas dessaturases envolvidas na síntese dos ácidos graxos de cadeia muito longa. São apresentadas as recomendações da razão ômega-6/ômega-3 na dieta, propostas em diversos países, sendo verificada a convergência para o intervalo de 4 a 5:1. São relacionados alimentos que podem contribuir para aumentar a ingestão do ácido alfa-linolênico e dos ácidos graxos de cadeia muito longa. A essencialidade dos ácidos graxos de cadeia muito longa é muito dependente do metabolismo do indivíduo, sendo que a razão n-6/n-3 da dieta exerce grande influência nesse sentido.Polyunsaturated fatty acids include the classes of fatty acids designated as omega-3 and omega-6. Very-long-chain polyunsaturated fatty acids as arachidonic and docosahexaenoic have important roles in the development and functioning of the brain and retina. This group of fatty acids cannot be synthesized by de novo pathway, but can be formed from linoleic and alpha-linolenic acid present in diet. In this article, the main factors that can inhibit desaturase enzymes activity involved in the synthesis of MLC-PUFAs are considered. Recommendations of omega-6/omega-3 ratio in diet proposed in several countries are presented, showing a coverage range from 4 to 5:1. Foods that are sources of alpha-linolenic acid and Very-long-chain are listed. The essentiality of Very-long-chain is very dependent of individual metabolism, and omega-6/omega-3 dietary ratio

The effect of temperature on the sensitivity of Daphnia magna to cyanobacteria is genus dependent.

Science.gov (United States)

Hochmuth, Jennifer D; De Schamphelaere, Karel A C

2014-10-01

In the present study, the authors investigated the effects of 6 different genera of cyanobacteria on multiple endpoints of Daphnia magna in a 21-d life table experiment conducted at 3 different temperatures (15 °C, 19 °C, and 23 °C). The specific aims were to test if the effect of temperature on Daphnia's sensitivity to cyanobacteria differed among different cyanobacteria and if the rank order from most to least harmful cyanobacteria to Daphnia reproduction changed or remained the same across the studied temperature range. Overall, the authors observed a decrease in harmful effects on reproduction with increasing temperature for Microcystis, Nodularia, and Aphanizomenon, and an increase in harmful effects with increasing temperature for Anabaena and Oscillatoria. No effect of temperature was observed on Daphnia sensitivity to Cylindrospermopsis. Harmful effects of Microcystis and Nodularia on reproduction appear to be mirrored by a decrease in length. On the other hand, harmful effects of Anabaena, Aphanizomenon, and Oscillatoria on reproduction were correlated with a decrease in intrinsic rate of natural increase, which was matched by a later onset of reproduction in exposures to Oscillatoria. In addition, the results suggest that the cyanobacteria rank order of harmfulness may change with temperature. Higher temperatures may increase the sensitivity of D. magna to the presence of some cyanobacteria (Anabaena and Oscillatoria) in their diet, whereas the harmful effects of others (Microcystis, Nodularia, and Aphanizomenon) may be reduced by higher temperatures. © 2014 SETAC.

Effect of pH and ionic strength on exposure and toxicity of encapsulated lambda-cyhalothrin to Daphnia magna.

Science.gov (United States)

Son, Jino; Hooven, Louisa A; Harper, Bryan; Harper, Stacey L

2015-12-15

Encapsulation of pesticide active ingredients in polymers has been widely employed to control the release of poorly water-soluble active ingredients. Given the high dispersibility of these encapsulated pesticides in water, they are expected to behave differently compared to their active ingredients; however, our current understanding of the fate and effects of encapsulated pesticides is still limited. In this study, we employed a central composite design (CCD) to investigate how pH and ionic strength (IS) affect the hydrodynamic diameter (HDD) and zeta potential of encapsulated λ-cyhalothrin and how those changes affect the exposure and toxicity to Daphnia magna. R(2) values greater than 0.82 and 0.84 for HDD and zeta potential, respectively, irrespective of incubation time suggest those changes could be predicted as a function of pH and IS. For HDD, the linear factor of pH and quadratic factor of pH×pH were found to be the most significant factors affecting the change of HDD at the beginning of incubation, whereas the effects of IS and IS×IS became significant as incubation time increased. For zeta potential, the linear factor of IS and quadratic factor of IS×IS were found to be the most dominant factors affecting the change of zeta potential of encapsulated λ-cyhalothrin, irrespective of incubation time. The toxicity tests with D. magna under exposure conditions in which HDD or zeta potential of encapsulated λ-cyhalothrin was maximized or minimized in the overlying water also clearly showed the worst-case exposure condition to D. magna was when the encapsulated λ-cyhalothrin is either stable or small in the overlying water. Our results show that water quality could modify the fate and toxicity of encapsulated λ-cyhalothrin in aquatic environments, suggesting understanding their aquatic interactions are critical in environmental risk assessment. Herein, we discuss the implications of our findings for risk assessment. Copyright © 2015 Elsevier B.V. All

Molecular cloning of manganese superoxide dismutase gene in the cladoceran Daphnia magna: Effects of microcystin, nitrite, and cadmium on gene expression profiles

Energy Technology Data Exchange (ETDEWEB)

Lyu, Kai; Zhu, Xuexia; Chen, Rui [Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023 (China); Chen, Yafen [State Key Laboratory for Lake Science and Environment, Nanjing Institute of Geography and Limnology, the Chinese Academy of Sciences, Nanjing 210008 (China); Yang, Zhou, E-mail: yangzhou@njnu.edu.cn [Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023 (China)

2014-03-01

Graphical abstract: - Highlights: • Daphnia magna MnSOD (Dm-MnSOD) was identified and revealed MnSOD-family features. • The expression of Dm-MnSOD decreased with increased developmental stages. • Dm-MnSOD transcript was kinetically up-regulated by microcystin, nitrite and Cd. • Response of SOD to ubiquitous waterborne pollutants in D. magna was elucidated. • Dm-MnSOD gene is a potential biomarker indicating pollutants in the environment. - Abstract: Superoxide dismutases (SODs) are metalloenzymes that represent one important line of defense against oxidative stress produced by reactive oxygen species in aerobic organisms. Generally, waterborne pollutants caused by irregular anthropogenic activities often result in oxidative damage in aquatic organisms. The aim of this study was to molecularly characterize the manganese superoxide dismutase gene (Dm-MnSOD) in the waterflea, Daphnia magna, and evaluate the mRNA expression patterns quantified by real-time PCR after exposure to three common waterborne pollutants (microcystin-LR, nitrite, and cadmium). The results showed that the full-length Dm-MnSOD sequence consists of 954 bp nucleotides, encoding 215 amino acids, showing well-conserved domains that are required for metal binding and several common characteristics, such as two MnSOD domains. The deduced amino acid sequence of Dm-MnSOD shared over 70% similarity with homologues from Bythograea thermydron, Dromia personata, Cancer pagurus, and Scylla paramamosain. Dm-MnSOD gene expression was up-regulated in response to exposure to the three chemicals tested. The overall results indicated that Dm-MnSOD gene is an inducible gene and potential biomarker indicating these pollutants in the environment.

Brain Serotonin Transporter Binding In a Minipig Model of Parkinson's Disease

DEFF Research Database (Denmark)

Lillethorup, Thea Pinholt; Glud, Andreas Nørgaard; Sørensen, Jens Christian Hedemann

minipigs were implanted in the cisterna magna with a catheter connected to a subcutaneous titanium injection port under sterile conditions. Six-eight weeks after recovery from the catheter implant, and after injections of sterile saline alone to verify patency, minipigs were scanned at baseline with [11C......]-3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)-benzonitrile (11C-DASB), a label of SERT availability. Four pigs then received eight weekly injections of lactacystin dissolved in sterile saline, and one pig received saline alone, directly into the CSF through the access port. They were scanned...... with DASB again after a cumulative dose of 200μg lactacystin. PET data were registered to an average minipig MRI atlas and processed using PMOD software. The binding potential (BPND) of DASB was obtained with the Logan graphical analysis and cerebellum activity as a region of non-displaceable binding...

Sagittal reconstruction computed tomography in metrizamide cisternography. Useful diagnostic procedure for malformations in craniovertebral junction and posterior fossa

Energy Technology Data Exchange (ETDEWEB)

Mochizuki, H.; Okita, N.; Fujii, T.; Yoshioka, M.; Saito, H. (Tohoku Univ., Sendai (Japan). School of Medicine)

1982-08-01

We studied the sagittal reconstruction technique in computed tomography with metrizamide. Ten ml of metrizamide, 170 mg iodine/ml in concentration, were injected by lumbar puncture. After diffusion of the injected metrizamide, axial computed tomograms were taken by thin slice width (5 mm) with overlapped technique. Then electrical sagittal reconstruction was carried out by optioned software. Injection of metrizamide, non-ionic water soluble contrast media, made clear contrasts among bone, brain parenchyma and cerebrospinal fluid with computed tomography. Sagittal reconstruction technique could reveal more precise details and accurate anatomical relations than ordinary axial computed tomography. This technique was applied on 3 cases (Arnold-Chiari malformation, large cisterna magna and partial agenesis cerebellar vermis), which demonstrated a useful diagnostic procedure for abnormalities of craniovertebral junction and posterior fossa. The adverse reactions of metrizamide were negligible in our series.

NMR images of non-communicating hydrocephalus associated with Dandy-Walker variant and achondroplasia

International Nuclear Information System (INIS)

Sato, Masaharu; Kuroda, Ryotaro; Watanabe, Masaru; Nakatani, Jiro; Ioku, Masahiko; Irisawa, Minoru; Hamada, Tatsumi; Ishida, Osamu

1988-01-01

Two cases of non-communicating hydrocephalus caused by a relatively rare etiology were reported. They were both diagnosed by means of nuclear magnetic resonance (NMR). The first patient, a 4-month-old boy, had Dandy-Walker variant, showing hypoplasia of the corpus callosum and the inferior vermis, and a large cyst behind the vermis, communicating with the subarachnoid space, as well as hydrocephalus; the fourth ventricle was partially reserved. The second patient, also a 4-month-old boy, had achondroplasia, resulting in a narrow foramen magnum; the disturbance of the outflow of the cerebro-spinal fluid around the cisterna magna was thought to be the cause of hydrocephalus in his case. The validity of NMR was demonstrated in the diagnoses of these conditions, for a high resolution was needed in examining the complicated structure of the posterior fossa. (author)

NMR images of non-communicating hydrocephalus associated with Dandy-Walker variant and achondroplasia

Energy Technology Data Exchange (ETDEWEB)

Sato, Masaharu; Kuroda, Ryotaro; Watanabe, Masaru; Nakatani, Jiro; Ioku, Masahiko; Irisawa, Minoru; Hamada, Tatsumi; Ishida, Osamu

1988-06-01

Two cases of non-communicating hydrocephalus caused by a relatively rare etiology were reported. They were both diagnosed by means of nuclear magnetic resonance (NMR). The first patient, a 4-month-old boy, had Dandy-Walker variant, showing hypoplasia of the corpus callosum and the inferior vermis, and a large cyst behind the vermis, communicating with the subarachnoid space, as well as hydrocephalus; the fourth ventricle was partially reserved. The second patient, also a 4-month-old boy, had achondroplasia, resulting in a narrow foramen magnum; the disturbance of the outflow of the cerebro-spinal fluid around the cisterna magna was thought to be the cause of hydrocephalus in his case. The validity of NMR was demonstrated in the diagnoses of these conditions, for a high resolution was needed in examining the complicated structure of the posterior fossa.

Effect of assisted reproductive technology on fetal brain development assessed by prenatal ultrasonography.

Science.gov (United States)

Yin, Linliang; Xu, Yongle; Li, Hong; Ling, Chen; Choy, Kwong Wai; Xia, Fei; Deng, Xuedong

2015-01-01

The aim was to evaluate whether assisted reproductive technology (ART) affects the development of the fetal central nervous system (CNS). This study was carried out on women with singleton pregnancies, including 427 women who became pregnant by ART and 32,859 women with natural conceptions (NCs). The cavum septum pellucidum (CSP) width, transverse cerebellar diameter (TCD), cisterna magna (CM) depth, and lateral ventricle width were measured by ultrasound for 72 normal ART fetuses and 201 normal NC fetuses. The malformation rate of CNS was determined for both groups. In both groups, significant positive correlations with gestational age were found for CSP width (ART: r=0.7841, NC: r=0.7864; P0.05). The development and malformation rate of the fetal CNS is not significantly different between ART and NC fetuses, thus, ART does not affect the development of the fetal brain.

Development and characterization of multiplex panels of polymorphic microsatellite loci in giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), using next-generation sequencing approach

Czech Academy of Sciences Publication Activity Database

Minárik, G.; Bazsalovicsová, E.; Zvijáková, Ĺ.; Štefka, Jan; Pálková, L.; Kraľová-Hromadová, I.

2014-01-01

Roč. 195, č. 1 (2014), s. 30-33 ISSN 0166-6851 Institutional support: RVO:60077344 Keywords : Short tandem repeats * Population genetics * Invasive parasite * Microsatellites * Fascioloides magna Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.787, year: 2014

Toxicidade aguda e risco ambiental do antibiótico oxitetraciclina para tilápia ( Oreochromis niloticus , Daphnia magna e Lemna minor

Directory of Open Access Journals (Sweden)

A.A. Machado

Full Text Available RESUMO O objetivo deste estudo foi classificar o antibiótico Terramicina(r de acordo com a toxicidade aguda e o risco de intoxicação ambiental para Oreochromis niloticus, Daphnia magna e Lemna minor, com base no seu ingrediente ativo oxitetraciclina (OTC. Além disso, observou-se a ocorrência de sinais de intoxicação aguda em peixes e o efeito da diluição do antibiótico sobre as variáveis de qualidade de água. Alevinos, neonatos e frondes foram expostos a concentrações de OTC. De acordo com os resultados dos testes de toxicidade aguda, a Terramicina(r foi classificada pela toxicidade aguda e pelo risco de intoxicação ambiental. Para O. niloticus, a CL(I50; 48h calculada foi de 6,92 mg L-1, para D. magna a CE(I50; 48h foi de 0,17mg.L-1, enquanto para L. minor a CI(I50;7d foi de 0,68 mg L-1. A Terramicina(r foi classificada como muito tóxica para O. niloticus e extremamente tóxica para D. magna e L. minor e causa risco de intoxicação ambiental para os três organismos testados. Concentrações de 7,5 e 8,0 mg L-1 de OTC reduziram a concentração de oxigênio dissolvido na água. De acordo com este estudo, a Terramicina(r não deve ser utilizada na aquicultura, pois é altamente tóxica e causa risco de intoxicação ambiental aos organismos teste.

The Open Education System, Anadolu University, Turkey: E-Transformation in a Mega-University

Science.gov (United States)

Latchem, Colin; Ozkul, Ali Ekrem; Aydin, Cengiz Hakan; Mutlu, Mehmet Emin

2006-01-01

Anadolu University in Turkey is one of the world's largest and least known mega-universities. Well over one million students in Turkey, the European Union and Northern Cyprus are enrolled in its Open Education System and yet few accounts of this dual-mode provider appear in the international literature. This article describes the evolution of the…

A quantitative evaluation of the environmental impact of the mega constellations

OpenAIRE

Rossi, A.; Alessi, E.M.; Valsecchi, G.B.; Lewis, H.; Radtke, J.; Bombardelli, C.; Bastida Virgili, B.

2017-01-01

The main focus of this work is to highlight the main parameters driving the future evolution of the debris environment, in presence of the planned LEO mega constellation of satellites. First, in order to identify the most important parameters that are actually driving the evolution of the environment and in an effort to discriminate between possibly equivalent scenarios, we applied tools from the statistical sciences, namely the Wilcoxon signed rank test, a non-parametric test which allows us...

MegaFlex Scale-Up Cost & Risk Reduction for >50kW Future Power Demands, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — As the MegaFlex solar array is scaled for power demands greater than 50kW over the next 20 years and deployed load requirements remain high or increase, advanced...

Effects of the cyanobacterial neurotoxin B-N-methylamino-L-alamine (BMAA) on the survival, mobility and reproduction of Daphnia magna

NARCIS (Netherlands)

Lürling, M.F.L.L.W.; Faassen, E.J.; Eenennaam, van J.S.

2011-01-01

In short-term tests and chronic life table assays, Daphnia magna was exposed to the cyanobacterial neurotoxic non-protein amino acid ß-N-methylamino-l-alanine (BMAA). BMAA was not acutely lethal to Daphnia (LC50–48h > 10 000 µg L-1), but reduced mobility (IC50–48h 40 µg L-1) and affected life

The Economic Effects of the Mega Sport Events on Tourism in the BRICS Countries Case

Directory of Open Access Journals (Sweden)

Iuliana Pop

2016-11-01

Full Text Available At the beginning of the 21st century, events tourism witnessed an impressive development in a series of countries due to the increase of the spare time and of the people’s income, to the cheaper and more diversified world transport, especially the air transport and due to the emergence of new destinations. Emergent countries, such as China and Russia, recorded not only an increase in the number of tourists but also in the revenues from tourism activities. One of the reasons is the opening of these countries frontiers in order to reaffirm their power on international level (Golubchikov, 2016. Besides the relaxation, business and religious tourism, the sport tourism becomes more and more important. It also comprises the tourism for mega sport events, such as the Summer and Winter Olympics or the World Championships in different sports. For the organising countries, there is a real challenge to ensure the investments for the infrastructure, although it supports their economic development, being used after the sport events conclusion. Considering the available data from the World Bank and the World Tourism Organization (UNWTO, the authors make a quantitative investigation regarding the impact of the mega sport events on the tourism phenomenon in the BRICS countries. The article also researches a small and specific group of countries (BRICS, considering a niche tourism phenomenon. The article aims to emphasize the role of the mega sport events in the BRICS countries, directly connected with their capacity to economically support the organization of these events and also with the desire to internationally promote their national values.

Mega-fire Recovery in Dry Conifer Forests of the Interior West

Science.gov (United States)

Malone, S. L.; Fornwalt, P.; Chambers, M. E.; Battaglia, M.

2015-12-01

Wildfire is a complex landscape process with great uncertainty in whether trends in size and severity are shifting trajectories for ecosystem recovery that are outside of the historical range of variability. Considering that wildfire size and severity is likely to increase into the future with a drier climate, it is important that we understand wildfire effects and ecosystem recovery. To evaluate how ecosystems recover from wildfire we measured spatial patterns in regeneration and mapped tree refugia within mega-fire perimeters (Hayman, Jasper, Bobcat, and Grizzly Gulch) in ponderosa pine (Pinus ponderosa) dominated forest. On average, high severity fire effects accounted for > 15% of burned area and increased with fire size. Areas with high severity fire effects contained 1 - 15% tree refugia cover, compared to 37 - 70% observed in low severity areas . Large high severity patches with low coverage of tree refugia, were more frequent in larger fires and regeneration distances required to initiate forest recovery far exceeded 1.5 canopy height or 200 m, distances where the vast majority of regeneration is likely to arise. Using a recovery model driven by distance, we estimate recovery times between 300 to > 1000 years for these mega-fires. In Western dry conifer forests, large patches of stand replacing fire are likely to lead to uneven aged forest and very long recovery times.

Modification of metal bioaccumulation and toxicity in Daphnia magna by titanium dioxide nanoparticles

International Nuclear Information System (INIS)

Tan, Cheng; Wang, Wen-Xiong

2014-01-01

Titanium dioxide (TiO 2 ) nanoparticles are widely used in water treatments, yet their influences on other contaminants in the water are not well studied. In this study, the aqueous uptake, assimilation efficiency, and toxicity of two ionic metals (cadmium-Cd, and zinc-Zn) in a freshwater zooplankton, Daphnia magna, were investigated following 2 days pre-exposure to nano-TiO 2 . Pre-exposure to 1 mg/L nano-TiO 2 resulted in a significant increase in Cd and Zn uptake from the dissolved phase. After the nano-TiO 2 in the guts were cleared, the uptake rates immediately recovered to the normal levels. Concurrent measurements of reactive oxygen species (ROS) and metallothioneins (MTs) suggested that the increased metal uptake was mainly due to the increased number of binding sites provided by nano-TiO 2 presented in the guts. Consistently, pre-exposure to nano-TiO 2 increased the toxicity of aqueous Cd and Zn due to enhanced uptake. Our study provides the evidence that nano-TiO 2 in the guts of animals could increase the uptake and toxicity of other contaminants. -- Highlights: • Dissolved Cd and Zn uptake in daphnids increased significantly after nano-TiO 2 pre-exposure. • Aqueous toxicity of Cd and Zn also increased after nano-TiO 2 pre-exposure. • Dietary assimilation of Cd and Zn was not affected after nano-TiO 2 pre-exposure. • Metal uptake recovered to normal levels after nano-TiO 2 in the guts were removed. • Nano-TiO 2 in the guts of animals could increase the uptake and toxicity of other contaminants. -- Nano-TiO 2 accumulation in Daphnia magna facilitated the uptake and toxicity of metal contaminants

Gene transcription profiles, global DNA methylation and potential transgenerational epigenetic effects related to Zn exposure history in Daphnia magna

International Nuclear Information System (INIS)

Vandegehuchte, Michiel B.; De Coninck, Dieter; Vandenbrouck, Tine; De Coen, Wim M.; Janssen, Colin R.

2010-01-01

A reduced level of DNA methylation has recently been described in both Zn-exposed and non-exposed offspring of Daphnia magna exposed to Zn. The hypothesis examined in this study is that DNA hypomethylation has an effect on gene transcription. A second hypothesis is that accumulative epigenetic effects can affect gene transcription in non-exposed offspring from parents with an exposure history of more than one generation. Transcriptional gene regulation was studied with a cDNA microarray. In the exposed and non-exposed hypomethylated daphnids, a large proportion of common genes were similarly up- or down-regulated, indicating a possible effect of the DNA hypomethylation. Two of these genes can be mechanistically involved in DNA methylation reduction. The similar transcriptional regulation of two and three genes in the F 0 and F 1 exposed daphnids on one hand and their non-exposed offspring on the other hand, could be the result of a one-generation temporary transgenerational epigenetic effect, which was not accumulative. - Zn-induced DNA hypomethylation is related to gene transcription in Daphnia magna and Zn exposure potentially induced limited temporary transgenerational effects on gene transcription.

Mega Thinking and Planning: An Introduction to Defining and Delivering Individual and Organizational Success

Science.gov (United States)

Kaufman, Roger

2009-01-01

All organizations are means to societal ends, and thus Mega thinking and planning starts with a primary focus on adding value for all stakeholders, including our shared society. It is pragmatic, realistic, practical, and ethical. Defining and achieving continual organizational success is possible. It relies on three basic elements: (1) a societal…

Multiple-endpoints gene alteration-based (MEGA) assay: A toxicogenomics approach for water quality assessment of wastewater effluents.

Science.gov (United States)

Fukushima, Toshikazu; Hara-Yamamura, Hiroe; Nakashima, Koji; Tan, Lea Chua; Okabe, Satoshi

2017-12-01

Wastewater effluents contain a significant number of toxic contaminants, which, even at low concentrations, display a wide variety of toxic actions. In this study, we developed a multiple-endpoints gene alteration-based (MEGA) assay, a real-time PCR-based transcriptomic analysis, to assess the water quality of wastewater effluents for human health risk assessment and management. Twenty-one genes from the human hepatoblastoma cell line (HepG2), covering the basic health-relevant stress responses such as response to xenobiotics, genotoxicity, and cytotoxicity, were selected and incorporated into the MEGA assay. The genes related to the p53-mediated DNA damage response and cytochrome P450 were selected as markers for genotoxicity and response to xenobiotics, respectively. Additionally, the genes that were dose-dependently regulated by exposure to the wastewater effluents were chosen as markers for cytotoxicity. The alterations in the expression of an individual gene, induced by exposure to the wastewater effluents, were evaluated by real-time PCR and the results were validated by genotoxicity (e.g., comet assay) and cell-based cytotoxicity tests. In summary, the MEGA assay is a real-time PCR-based assay that targets cellular responses to contaminants present in wastewater effluents at the transcriptional level; it is rapid, cost-effective, and high-throughput and can thus complement any chemical analysis for water quality assessment and management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dopo il Grande Evento: politiche “utili” per la mobilità Beyond the Mega Events: “Useful” Policies for Urban Mobility

Directory of Open Access Journals (Sweden)

Andrea Ceudech

2008-08-01

Full Text Available Il contributo indaga i limiti delle politiche urbane e in particolare di quelle sulla mobilità attuate per i Grandi Eventi, evidenziando in molti casi la tendenza a privilegiare la realizzazione di infrastrutture, più che politiche sui servizi, la cui reale utilità è spesso messa in dubbio dalla pratica e i cui costi manutentivi divengono spesso nuovi carichi per la collettività. Sulla base di una breve rassegna delle politiche sulla mobilità maggiormente implementate nella preparazione e gestione dei Grandi Eventi, il contributo evidenzia in maniera critica punti di forza e punti di debolezza delle esperienze analizzate in riferimento sia alla gestione del grande evento, sia in riferimento alla loro reale utilità per la collettività dopo che il grande evento è terminato. Nell’ultima parte del contributo si evidenziano i principali requisiti che le politiche sulla mobilità devono possedere affinché apportino reali vantaggi alla città anche una volta che il Grande Evento è terminato.The paper analyses, through different examples, the limits of the urban mobility policies implemented for mega events, highlighting the tendency to privilege the infrastructure realization, more than policies on services, whose real usefulness is often put in doubt from the practice and whose maintenance often become a new cost for the community. On the base of a short review of the mobility policies mainly implemented in the preparation and management of the mega events, the paper highlights, from a critical point of view, the strengths and weaknesses of some experiences with reference to the real usefulness of urban mobility for the community beyond the mega event. The outcomes and the so-called “legacy” of the mega events for the cities are very different. Mega sport events, like the Olympic Games, have often involved only the realization of works for the event while events like the International Expositions have determined the acquisition of

Daphnia magna and Xenopus laevis as in vivo models to probe toxicity and uptake of quantum dots functionalized with gH625

Directory of Open Access Journals (Sweden)

Galdiero E

2017-04-01

Full Text Available Emilia Galdiero,1 Annarita Falanga,2 Antonietta Siciliano,1 Valeria Maselli,1 Marco Guida,1 Rosa Carotenuto,1 Margherita Tussellino,1 Lucia Lombardi,3 Giovanna Benvenuto,4 Stefania Galdiero2 1Department of Biology, 2Department of Pharmacy and CiRPEB, University of Naples Federico II, 3Department of Experimental Medicine, Second University of Naples, 4Stazione Zoologica Anton Dohrn, Villa Comunale, Napoli, Italy Abstract: The use of quantum dots (QDs for nanomedicine is hampered by their potential toxicologic effects and difficulties with delivery into the cell interior. We accomplished an in vivo study exploiting Daphnia magna and Xenopus laevis to evaluate both toxicity and uptake of QDs coated with the membranotropic peptide gH625 derived from the glycoprotein H of herpes simplex virus and widely used for drug delivery studies. We evaluated and compared the effects of QDs and gH625-QDs on the survival, uptake, induction of several responsive pathways and genotoxicity in D. magna, and we found that QDs coating plays a key role. Moreover, studies on X. laevis embryos allowed to better understand their cell/tissue localization and delivery efficacy. X. laevis embryos raised in Frog Embryo Teratogenesis Assay-Xenopus containing QDs or gH625-QDs showed that both nanoparticles localized in the gills, lung and intestine, but they showed different distributions, indicating that the uptake of gH625-QDs was enhanced; the functionalized QDs had a significantly lower toxic effect on embryos’ survival and phenotypes. We observed that D. magna and X. laevis are useful in vivo models for toxicity and drug delivery studies. Keywords: membranotropic peptide, delivery, blood–brain barrier, nanoparticles, genotoxicity

Metallothionein and Hsp70 trade-off against one another in Daphnia magna cross-tolerance to cadmium and heat stress

Energy Technology Data Exchange (ETDEWEB)

Haap, Timo, E-mail: timo.haap@gmx.de; Schwarz, Simon; Köhler, Heinz-R.

2016-01-15

Highlights: • Cadmium acclimation of two Daphnia magna clones which differed in Cd sensitivity and Hsp70 levels. • Two distinct metal-handling strategies regarding Hsp70 and MT expression were observed. • High Hsp70 levels did not confer an increase in Cd and heat stress tolerance. • Our results indicate a trade-off between Hsp70 and MT. - Abstract: The association between the insensitivity of adapted ecotypes of invertebrates to environmental stress, such as heavy metal pollution, and overall low Hsp levels characterizing these organisms has been attracting attention in various studies. The present study seeks to induce and examine this phenomenon in Daphnia magna by multigenerational acclimation to cadmium in a controlled laboratory setting. In this experiment, interclonal variation was examined: two clones of D. magna that have previously been characterized to diverge regarding their cadmium resistance and levels of the stress protein Hsp70, were continuously exposed to a sublethal concentration of Cd over four generations to study the effects of acclimation on Hsp70, metallothionein (MT), reproduction and cross-tolerance to heat stress. The two clones differed in all the measured parameters in a characteristic way, clone T displaying Cd and heat resistance, lower Hsp70 levels and offspring numbers on the one hand and higher MT expression on the other hand, clone S the opposite for all these parameters. We observed only slight acclimation-induced changes in constitutive Hsp70 levels and reproductive output. The differences in MT expression between clones as well as between acclimated organisms and controls give evidence for MT accounting for the higher Cd tolerance of clone T. Overall high Hsp70 levels of clone S did not confer cross tolerance to heat stress, contrary to common expectations. Our results suggest a trade-off between the efforts to limit the proteotoxic symptoms of Cd toxicity by Hsp70 induction and those to sequester and detoxify Cd by

Sphingomyelin synthesis in rat liver occurs predominantly at the cis and medial cisternae of the Golgi apparatus

International Nuclear Information System (INIS)

Futerman, A.H.; Stieger, B.; Hubbard, A.L.; Pagano, R.E.

1990-01-01

The intracellular site of sphingomyelin (SM) synthesis was examined in subcellular fractions from rat liver using a radioactive ceramide analog N-([1-14C]hexanoyl)-D-erythro-sphingosine. This lipid readily transferred from a complex with bovine serum albumin to liver fractions without disrupting the membranes, and was metabolized to radioactive SM. To prevent degradation of the newly synthesized SM to ceramide, all experiments were performed in the presence of EDTA to minimize neutral sphingomyelinase activity and at neutral pH to minimize acid sphingomyelinase activity. An intact Golgi apparatus fraction gave an 85-98-fold enrichment of SM synthesis and a 58-83-fold enrichment of galactosyltransferase activity. Controlled trypsin digestion demonstrated that SM synthesis was localized to the lumen of intact Golgi apparatus vesicles. Although small amounts of SM synthesis were detected in plasma membrane and rough microsome fractions, after accounting for contamination by Golgi apparatus membranes, their combined activity contributed less than 13% of the total SM synthesis in rat liver. Subfractions of the Golgi apparatus were obtained and characterized by immunoblotting and biochemical assays using cis/medial (mannosidase II) and trans (sialyltransferase and galactosyltransferase) Golgi apparatus markers. The specific activity of SM synthesis was highest in enriched cis and medial fractions but far lower in a trans fraction. We conclude that SM synthesis in rat liver occurs predominantly in the cis and medial cisternae of the Golgi apparatus and not at the plasma membrane or endoplasmic reticulum as has been previously suggested

Tsunami Hazard Assessment of Coastal South Africa Based on Mega-Earthquakes of Remote Subduction Zones

Science.gov (United States)

Kijko, Andrzej; Smit, Ansie; Papadopoulos, Gerassimos A.; Novikova, Tatyana

2017-11-01

After the mega-earthquakes and concomitant devastating tsunamis in Sumatra (2004) and Japan (2011), we launched an investigation into the potential risk of tsunami hazard to the coastal cities of South Africa. This paper presents the analysis of the seismic hazard of seismogenic sources that could potentially generate tsunamis, as well as the analysis of the tsunami hazard to coastal areas of South Africa. The subduction zones of Makran, South Sandwich Island, Sumatra, and the Andaman Islands were identified as possible sources of mega-earthquakes and tsunamis that could affect the African coast. Numerical tsunami simulations were used to investigate the realistic and worst-case scenarios that could be generated by these subduction zones. The simulated tsunami amplitudes and run-up heights calculated for the coastal cities of Cape Town, Durban, and Port Elizabeth are relatively small and therefore pose no real risk to the South African coast. However, only distant tsunamigenic sources were considered and the results should therefore be viewed as preliminary.

Tsunami Hazard Assessment of Coastal South Africa Based on Mega-Earthquakes of Remote Subduction Zones

Science.gov (United States)

Kijko, Andrzej; Smit, Ansie; Papadopoulos, Gerassimos A.; Novikova, Tatyana

2018-04-01

After the mega-earthquakes and concomitant devastating tsunamis in Sumatra (2004) and Japan (2011), we launched an investigation into the potential risk of tsunami hazard to the coastal cities of South Africa. This paper presents the analysis of the seismic hazard of seismogenic sources that could potentially generate tsunamis, as well as the analysis of the tsunami hazard to coastal areas of South Africa. The subduction zones of Makran, South Sandwich Island, Sumatra, and the Andaman Islands were identified as possible sources of mega-earthquakes and tsunamis that could affect the African coast. Numerical tsunami simulations were used to investigate the realistic and worst-case scenarios that could be generated by these subduction zones. The simulated tsunami amplitudes and run-up heights calculated for the coastal cities of Cape Town, Durban, and Port Elizabeth are relatively small and therefore pose no real risk to the South African coast. However, only distant tsunamigenic sources were considered and the results should therefore be viewed as preliminary.

Transgenerational effects and recovery of microplastics exposure in model populations of the freshwater cladoceran Daphnia magna Straus.

Science.gov (United States)

Martins, Alexandra; Guilhermino, Lúcia

2018-08-01

The environmental contamination by microplastics is a global challenge to ecosystem and human health, and the knowledge on the long-term effects of such particles is limited. Thus, the effects of microplastics and post-exposure recovery were investigated over 4 generations (F 0 , F 1 , F 2 , F 3 ) using Daphnia magna as model. Effect criteria were parental mortality, growth, several reproductive parameters, and population growth rate. Microplastics exposure (0.1mg/l of pristine polymer microspheres 1-5μm diameter) caused parental mortality (10-100%), and significantly (p≤0.05) decreased growth, reproduction, and population growth rate leading to the extinction of the microplastics-exposed model population in the F 1 generation. Females descending from those exposed to microplastics in F 0 and exposed to clean medium presented some recovery but up to the F 3 generation they still had significantly (p≤0.05) reduced growth, reproduction, and population growth rate. Overall, these results indicate that D. magna recovery from chronic exposure to microplastics may take several generations, and that the continuous exposure over generations to microplastics may cause population extinction. These findings have implications to aquatic ecosystem functioning and services, and raise concern on the long-term animal and human exposure to microplastics through diverse routes. Copyright © 2018. Published by Elsevier B.V.

The Kalimantan Border Oil Palm Mega-project

Energy Technology Data Exchange (ETDEWEB)

Wakker, E. [AIDEnvironment, Amsterdam (Netherlands)

2006-04-15

A few years ago, the Indonesian government and sections of the palm oil industry united in the Indonesian Palm Oil Commission (IPOC) to undertake efforts to restore the atrocious public image that the palm oil industry had earned abroad for its role in the demise of Indonesia's tropical rainforests, the massive forest fires and haze in 1997-1998, and for the widespread conflicts between plantation companies and local communities. If IPOC succeeded in restoring the palm oil industry's image abroad, it was shattered again after June 2005 when the Indonesian Minister of Agriculture revealed details of a government plan to develop the world's largest oil palm plantation in a 5-10 kilometer band along the border of Kalimantan and Malaysia. To finance the USD 567 million plantation project, the Indonesian President and Chamber of Commerce and Industry (KADIN) had already met up with the Chinese government and private sector several times, resulting in Memoranda of Understanding between (among other) the Artha Graha and Sinar Mas groups from Indonesia and the Chinese CITIC group and Chinese Development Bank (CDB). The oil palm mega-project, launched in Indonesia under the banner of 'bringing prosperity, security and environmental protection to the Kalimantan border area', turned sour when a business plan developed by the Indonesian State Plantation Corporation (PTPN) began to circulate. This document contained a map that showed beyond doubt how the 1.8 million hectare oil palm project would trash the primary forests of three National Parks, cut through rugged slopes and mountains utterly unsuitable for oil palm cultivation and annihilate the customary rights land of the indigenous Dayak communities in the border area. This report describes what has come of the Kalimantan border oil palm mega-plan since it was announced, who is involved and what research, lobby and campaigning has led to so far. In particular, this study aims to inform civil

The Kalimantan Border Oil Palm Mega-project

International Nuclear Information System (INIS)

Wakker, E.

2006-04-01

A few years ago, the Indonesian government and sections of the palm oil industry united in the Indonesian Palm Oil Commission (IPOC) to undertake efforts to restore the atrocious public image that the palm oil industry had earned abroad for its role in the demise of Indonesia's tropical rainforests, the massive forest fires and haze in 1997-1998, and for the widespread conflicts between plantation companies and local communities. If IPOC succeeded in restoring the palm oil industry's image abroad, it was shattered again after June 2005 when the Indonesian Minister of Agriculture revealed details of a government plan to develop the world's largest oil palm plantation in a 5-10 kilometer band along the border of Kalimantan and Malaysia. To finance the USD 567 million plantation project, the Indonesian President and Chamber of Commerce and Industry (KADIN) had already met up with the Chinese government and private sector several times, resulting in Memoranda of Understanding between (among other) the Artha Graha and Sinar Mas groups from Indonesia and the Chinese CITIC group and Chinese Development Bank (CDB). The oil palm mega-project, launched in Indonesia under the banner of 'bringing prosperity, security and environmental protection to the Kalimantan border area', turned sour when a business plan developed by the Indonesian State Plantation Corporation (PTPN) began to circulate. This document contained a map that showed beyond doubt how the 1.8 million hectare oil palm project would trash the primary forests of three National Parks, cut through rugged slopes and mountains utterly unsuitable for oil palm cultivation and annihilate the customary rights land of the indigenous Dayak communities in the border area. This report describes what has come of the Kalimantan border oil palm mega-plan since it was announced, who is involved and what research, lobby and campaigning has led to so far. In particular, this study aims to inform civil society organizations, palm oil

Voxel-based morphometry multi-center mega-analysis of brain structure in social anxiety disorder

Directory of Open Access Journals (Sweden)

Janna Marie Bas-Hoogendam

2017-01-01

An international multi-center mega-analysis on the largest database of SAD structural T1-weighted 3T MRI scans to date was performed to compare GM volume of SAD-patients (n = 174 and healthy control (HC-participants (n = 213 using voxel-based morphometry. A hypothesis-driven region of interest (ROI approach was used, focusing on the basal ganglia, the amygdala-hippocampal complex, the prefrontal cortex, and the parietal cortex. SAD-patients had larger GM volume in the dorsal striatum when compared to HC-participants. This increase correlated positively with the severity of self-reported social anxiety symptoms. No SAD-related differences in GM volume were present in the other ROIs. Thereby, the results of this mega-analysis suggest a role for the dorsal striatum in SAD, but previously reported SAD-related changes in GM in the amygdala, hippocampus, precuneus, prefrontal cortex and parietal regions were not replicated. Our findings emphasize the importance of large sample imaging studies and the need for meta-analyses like those performed by the Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA Consortium.

Malaysian Mega Science Framework: The Need for Social Impact and Sustainability Assessment

OpenAIRE

Ahmad Zainal A.; Ahmad Zulfadli

2015-01-01

This review focuses on issues surrounding wastewater management as part of the National Sustainable Development (2013-2050) under the Malaysian Mega Science Framework. In line with the national priority area of water security, this review will highlight the technical reports compiled by the Academy of Sciences Malaysia (ASM) on the challenges of water resource development and wastewater management and treatment. The discussion will dwell on the social impact of pollution in water and wastewat...

Analyzing the capacity of the Daphnia magna and Pseudokirchneriella subcapitata bioavailability models to predict chronic zinc toxicity at high pH and low calcium concentrations and formulation of a generalized bioavailability model for D. magna.

Science.gov (United States)

Van Regenmortel, Tina; Berteloot, Olivier; Janssen, Colin R; De Schamphelaere, Karel A C

2017-10-01

Risk assessment in the European Union implements Zn bioavailability models to derive predicted-no-effect concentrations for Zn. These models are validated within certain boundaries (i.e., pH ≤ 8 and Ca concentrations ≥ 5mg/L), but a substantial fraction of the European surface waters falls outside these boundaries. Therefore, we evaluated whether the chronic Zn biotic ligand model (BLM) for Daphnia magna and the chronic bioavailability model for Pseudokirchneriella subcapitata could be extrapolated to pH > 8 and Ca concentrations model can accurately predict Zn toxicity for Ca concentrations down to 0.8 mg/L and pH values up to 8.5. Because the chronic Zn BLM for D. magna could not be extrapolated beyond its validity boundaries for pH, a generalized bioavailability model (gBAM) was developed. Of 4 gBAMs developed, we recommend the use of gBAM-D, which combines a log-linear relation between the 21-d median effective concentrations (expressed as free Zn 2+ ion activity) and pH, with more conventional BLM-type competition constants for Na, Ca, and Mg. This model is a first step in further improving the accuracy of chronic toxicity predictions of Zn as a function of water chemistry, which can decrease the uncertainty in implementing the bioavailability-based predicted-no-effect concentration in the risk assessment of high-pH and low-Ca concentration regions in Europe. Environ Toxicol Chem 2017;36:2781-2798. © 2017 SETAC. © 2017 SETAC.

Mega-events, Local Economies, and Global Status: What Happened before the 2008 Olympics in Beijing and the 2010 World Expo in Shanghai

Directory of Open Access Journals (Sweden)

Jian Sun

2010-01-01

Full Text Available Mega-events such as the World Cup and the Olympics have been used for economic development, urban transformation and global status enhancement. Beijing and Shanghai embraced these purposes when they won the bids for the 2008 Olympics and the 2010 World Expo respectively. This article examines the pre-event economic changes in Beijing and Shanghai that are associated with their pursuit of mega-events. Changes in a group of economic indicators are tracked from 1997 to 2006. It was found that after winning the bids for the Olympics and the World Expo, Beijing and Shanghai experienced greater growth in construction and tourism, a speeding-up in economic development and restructuring, and an improvement in physical infrastructure. However, the enhancement of global exposure was not accompanied by growth in foreign trade and in the finance, insurance and real estate (FIRE industries. The empirical analyses place the mega-events in large economic contexts and provide a base for future post-event studies.

Tsunami simulations of mega-thrust earthquakes in the Nankai–Tonankai Trough (Japan) based on stochastic rupture scenarios

KAUST Repository

Goda, Katsuichiro; Yasuda, Tomohiro; Mai, Paul Martin; Maruyama, Takuma; Mori, Nobuhito

2017-01-01

In this study, earthquake rupture models for future mega-thrust earthquakes in the Nankai–Tonankai subduction zone are developed by incorporating the main characteristics of inverted source models of the 2011 Tohoku earthquake. These scenario

The dilemma of dykes - Risk and opportunities in a simulation of geomorphology at mega timescales

NARCIS (Netherlands)

Hagen - Zanker, A.H.; de Vries, Ies; Hartholt, H.

2007-01-01

SimDelta dynamically simulates the geomorphology of the ‘Dutch Delta’ at a mega time scale. Scientifically a success, the model has scope for development as a game. Through challenging game play policy makers, spatial planners and students learn about the dilemmas posed by short and long term

Unemployment, Entrepreneurial Education and Mega Universities: Challenges to Expanding Access in Education in Nigeria University

Science.gov (United States)

Undie, John Atewhoble; Okafor, Victor

2014-01-01

In fundamental economics, individuals acquired education for two broad reasons, as an investment and as consumption. The investment function of education has continued to create tension for job search leading to cases of unemployment. Entrepreneurship education and establishment of mega universities have been identified as panaceas. This paper…

Pembelajaran Embedded System Berbasis Arduino Mega 2560 dan MIT App Inventor

OpenAIRE

Tukadi, Tukadi

2017-01-01

This paper describes the learning process of the Embedded System course with a practical approach based on Arduino Mega 2560 and Android using MIT App inventor software. Learning materials include digital I / O and analog I / O access via android mobile phone. The method used in its implementation premises to provide tasks in the form of projects. The next step is to find the theories that can support in completing the project task. The project task is to control or read electronic devices co...

Acute and chronic effects from pulse exposure of D. magna to silver and copper oxide nanoparticles

DEFF Research Database (Denmark)

Sørensen, Sara Nørgaard; Lützhøft, Hans-Christian Holten; Rasmussen, Rose

2016-01-01

Aquatic toxicity testing of nanoparticles (NPs) is challenged by their dynamic behavior in test suspensions. The resulting difficulties in controlling and characterizing exposure concentrations are detrimental to the generation of concentration-response data needed for hazard identification of NPs...... is an environmentally relevant exposure scenario for NPs, which for AgNPs and CuONPs enables more stable exposures and cause acute immobility of D. magna comparable to continuous 24 h exposures. Pulse exposure is likely relevant and applicable for other toxic and dissolving metal NPs, but this requires further research....

Mechanistic study of the toxicity of ionizing radiation in Daphnia magna

Energy Technology Data Exchange (ETDEWEB)

Parisot, F.; Alonzo, F. [Institut de Radioprotection et de Surete Nucleaire, IRSN/PRP-ENV/SERIS/LECO, Laboratoire d' Ecotoxicologie des Radionucleides, Cadarache (France); Bourdineaud, J.P. [UMR CNRS 5805 EPOC - OASU Station Marine d' Arcachon Universite Bordeaux 1, Arcachon (France); Poggiale, J.C. [Mediterranean Institute of Oceanography - MIO - UMR 7294 Pytheas Institute - OSU, Aix-Marseille University, Marseille (France)

2014-07-01

In the last decade, the ecological impact of ionizing radiation has emerged as a growing scientific concern for ecosystems protection. However, the assessment of potential radiological effects on the environment is hampered by both a gap of available scientific data and a lack in proven methods. Understanding how ionizing radiation affects wildlife at biologically and ecologically relevant scales is a major issue in environmental protection. This issue is one of the objectives of the Strategic Research Agenda (SRA) developed in the framework of the European program STAR (Strategy for Allied Radioecology). In this context, the present PhD project aims to evaluate chronic effects of external Cs-137 gamma radiation at low doses on a representative species of aquatic ecosystems, the cladoceran crustacean Daphnia magna. More precisely, the objectives of this study are to evaluate multi-generational effects of irradiation on: (i) genotoxic effects and their potential consequences on survival, somatic growth and fecundity, (ii) the energy budget and (iii) the population dynamics of Daphnia. An experimental design was developed to expose daphnids to low doses of ionizing radiation ranging from 0,008 to 32 mGy.h{sup -1} across 3 successive generations (75 days). DNA damages were assessed using random amplified polymorphic DNA and real time PCR (RAPD - PCR). Effects on survival, somatic growth and fecundity were monitored for 21-25 days in each generation, from hatching to release of brood 5. Our aim is to: examine a potential correlation between molecular (DNA) damage and effects observed at the individual level (survival, somatic growth and fecundity) across generations and test the suitability of DNA damage as an early indice of future trans-generational effects. As a future perspective, individual and molecular effects data will be analysed using a DEBtox model (Dynamic Energy Budget Applied to Toxicology) in order to identify the metabolic modes of action of ionizing

Defining a quantitative framework for evaluation and optimisation of the environmental impacts of mega-event projects.

Science.gov (United States)

Parkes, Olga; Lettieri, Paola; Bogle, I David L

2016-02-01

This paper presents a novel quantitative methodology for the evaluation and optimisation of the environmental impacts of the whole life cycle of a mega-event project: construction and staging the event and post-event site redevelopment and operation. Within the proposed framework, a mathematical model has been developed that takes into account greenhouse gas (GHG) emissions resulting from use of transportation fuel, energy, water and construction materials used at all stages of the mega-event project. The model is applied to a case study - the London Olympic Park. Three potential post-event site design scenarios of the Park have been developed: Business as Usual (BAU), Commercial World (CW) and High Rise High Density (HRHD). A quantitative summary of results demonstrates that the highest GHG emissions associated with the actual event are almost negligible compared to those associated with the legacy phase. The highest share of emissions in the legacy phase is attributed to embodied emissions from construction materials (almost 50% for the BAU and HRHD scenarios) and emissions resulting from the transportation of residents, visitors and employees to/from the site (almost 60% for the CW scenario). The BAU scenario is the one with the lowest GHG emissions compared to the other scenarios. The results also demonstrate how post-event site design scenarios can be optimised to minimise the GHG emissions. The overall outcomes illustrate how the proposed framework can be used to support decision making process for mega-event projects planning. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of an anionic surfactant (FFD-6) on the energy and information flow between a primary producer (Scenedesmus obliquus) and a consumer (Daphnia magna)

NARCIS (Netherlands)

Lürling, M.; de Lange, H.J.; Peeters, E.T.H.M.

2011-01-01

The effects of a commercially available anionic surfactant solution (FFD-6) on growth and morphology of a common green alga (Scenedesmus obliquus) and on survival and clearance rates of the water flea Daphnia magna were studied. The surfactant-solution elicited a morphological response (formation of

Sprawl and mega-events: Economic growth and recent urban expansion in a city losing its competitive edge (Athens, Greece

Directory of Open Access Journals (Sweden)

Luca Salvati

2017-12-01

Full Text Available In the new context of contemporary cities, local competitiveness for financial resources has grown more than ever, resulting in cities characterised by important socioeconomic transformations. Earlier studies addressed the relation between urban expansion, socioeconomic development and mega-events only for specific areas and types of urban growth, often overlooking the role of mega-events in fuelling urban sprawl. As the host of the 2004 Olympic Games, Athens, Greece is a paradigmatic example for emerging cities hosting mega-events due to the close interconnection between the Olympics, infrastructure development and urban sprawl. This article connects the latent relationship between economic expansion driven by the Olympic Games and laissez-faire urbanism to the long-term unregulated urban expansion characterising Athens’s development. By providing room for the original wave of sprawl, the resulting socioeconomic context is interpreted as a signal of the weakness of the “competitive city” framework in poorly planned and long-deregulated urban contexts such as Athens. A comprehensive analysis of recent phases of economic growth and discontinuous urban expansion thus provides further insight into understanding sprawl processes in today’s cities, and helps distinguish the morphological patterns and socioeconomic dynamics that characterise urban expansion during sequential cycles of economic expansion and recession.

Radiographic studies of the ventricles in syringomyelia

International Nuclear Information System (INIS)

West, R.J.; Williams, B.

1980-01-01

Radiographic investigations of 171 patients with communicating syringomyelia have been reviewed. Hydrocephalus was found in one third of the cases and has occasionally progressed after operation on the posterior fossa, sometimes with accompanying clinical deterioration. The outlets of the fourth ventricle were usually abnormal; tonsillar descent, arachnoiditis and both together were seen. Arachnoiditis correlated strongly with a history of difficult birth. The foramen of Magendie was sometimes patent and sometimes blocked. There was no consistent level of occulusion corresponding to a persistent roof of the fourth ventricle. The cisterna magna was usually small or obliterated but some examples of large cisterns or subarachnoid pouches were found. Radiological demonstration of a communication from the fourth ventricle to the syrinx occurred in only seven patients by positive contrast material and not by air. It is suggested that a sizable communication is rare at the time when patients seek treatment. (orig.)

Progressive brain compression

International Nuclear Information System (INIS)

Thuomas, K.AA.; Inst. of Surgical Research, National Hospital, Oslo; Vlajkovic, S.; Inst. of Surgical Research, National Hospital, Oslo; Ganz, J.C.; Inst. of Surgical Research, National Hospital, Oslo; Nilsson, P.; Inst. of Surgical Research, National Hospital, Oslo; Bergstroem, K.; Inst. of Surgical Research, National Hospital, Oslo; Ponten, U.; Inst. of Surgical Research, National Hospital, Oslo; Zwetnow, N.N.; Inst. of Surgical Research, National Hospital, Oslo

1993-01-01

Continuous recording of vital physiological variables and sequential MR imaging were performed simultaneously during continuous expansion of an epidural rubber balloon over the left hemisphere in anaesthetised dogs. Balloon expansion led to a progressive and slgithly nonlinear rise in intracranial CSF pressures and a full in local perfusion pressures. Changes in systemic arterial pressure, pulse rate, and respiration rate usually appeared at a balloon volume of 4% to 5% of the intracranial volume (reaction volume), together with a marked transtentorial pressure gradient and MR imaging changes consistent with tentorial herniation. Respiratory arrest occurred at a balloon volume of approximately 10% of the intracranial volume (apnoea volume), which was associated with occulsion of the cisterna magna, consistent with some degree of foramen magnum herniation. Increase in tissue water was observed beginning at approximately the reaction volume, presumably due to ischaemic oedema, due to the fall in perfusion pressures. (orig.)

[A microbiological investigation of the effectiveness of Micro Megas E-spray].

Science.gov (United States)

Kardel, K; Hegna, I K; Kardel, M

1976-06-01

The disinfecting effect of Micro Megas E-spray was tested using a microbiological technique which also included a practical test. Contra-angels and straight handpieces which were sprayed after being used for treatment on patients, and then dried and incubated in a liquid medium, showed a marked growth of microorganisms. The spray had a weak and barely significant growth inhibiting effect on contaminated, simulated instrument surfaces. using Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus as test bacteria. It is concluded that the spray is not suitable for distinfection of contra-angels and straight handpieces.

Narrow linewidth picosecond UV pulsed laser with mega-watt peak power.

Science.gov (United States)

Huang, Chunning; Deibele, Craig; Liu, Yun

2013-04-08

We demonstrate a master oscillator power amplifier (MOPA) burst mode laser system that generates 66 ps/402.5 MHz pulses with mega-watt peak power at 355 nm. The seed laser consists of a single frequency fiber laser (linewidth laser is operating in a 5-μs/10-Hz macropulse mode. The laser output has a transform-limited spectrum with a very narrow linewidth of individual longitudinal modes. The immediate application of the laser system is the laser-assisted hydrogen ion beam stripping for the Spallation Neutron Source (SNS).

Study of the uranium effects on energy budget and population dynamics in Daphnia magna

International Nuclear Information System (INIS)

Massarin, S.

2010-01-01

This work aimed to study effects of uranium on energy budget and population dynamics in Daphnia magna a representative micro-crustacean of freshwater ecosystems. An experimental study of uranium toxicity on physiology (nutrition, respiration) and life history (survival, growth and reproduction) of D. magna was carried out, based on exposures over one, two or three successive generations (F0, F1 and F2) started with neonates from 1. or 5. brood, at 0, 10, 25 and 75 μg U.L -1 . Results showed that toxic effects increased across generations (partially due to daphnid exposure during embryogenesis) and that individuals from 1. brood were more sensitive than individuals from 5. brood. Significant reductions in assimilation rates, measured using a radio-tracing method with 14 C-labelled food, allowed us to identify an effect on assimilation as the mode of action for uranium, in agreement with important damages in the integrity of intestinal epithelium observed by optic microscopy. Integrating results in a dynamic energy budget model (DEBtox) yielded estimated no effect concentrations (NEC) of 9.37, 8.21 and 2.31 μg U.L -1 above which organism functions were altered in generations F0, F1 and F2, respectively. Combining DEBtox with matrix models allowed us to extrapolate consequences on asymptotic population growth rate (λ), a relevant endpoint in an ecological context. Simulations predicted an increase in uranium impact across generations with reduction of λ in F0 and population extinctions at 51-59 μg U.L -1 in F1 and 39-41 μg U.L -1 in F2. Simulations emphasized the importance of considering the most sensitive individuals while determining population response. (author)

Deep sea mega-geomorphology: Progress and problems

Science.gov (United States)

Bryan, W. B.

1985-01-01

Historically, marine geologists have always worked with mega-scale morphology. This is a consequence both of the scale of the ocean basins and of the low resolution of the observational remote sensing tools available until very recently. In fact, studies of deep sea morphology have suffered from a serious gap in observational scale. Traditional wide-beam echo sounding gave images on a scale of miles, while deep sea photography has been limited to scales of a few tens of meters. Recent development of modern narrow-beam echo sounding coupled with computer-controlled swath mapping systems, and development of high-resolution deep-towed side-scan sonar, are rapidly filling in the scale gap. These technologies also can resolve morphologic detail on a scale of a few meters or less. As has also been true in planetary imaging projects, the ability to observe phenomena over a range of scales has proved very effective in both defining processes and in placing them in proper context.

Impacts of Mega-droughts on Water and Food Security in the Indo-Gangetic Plains: A Paleoclimate Scenario Analysis

Science.gov (United States)

Zhu, T.; Pitois, G.; Ringler, C.; Wang, D.; Rosegrant, M. W.

2014-12-01

Spanning over Pakistan, northern India, Nepal, and Bangladesh, the Indo-Gangetic Plains (IGP) is the home of several hundred million people and the "bread basket" for much of South Asia. The flat terrain, fertile soils, and favorable climate of the IGP make it agriculturally productive. However prolonged droughts caused by consecutive monsoon failures can seriously affect crop production and social wellbeing, in particular for the eastern part of the plains where agriculture remains largely rain-fed. Severe droughts were observed in the IGP historically, and recent paleoclimate studies reveal that more severe and long-lasting "mega-droughts" had happened in the distant past. Agricultural losses from major droughts can dramatically affect food systems and increase the vulnerability of resource-poor people given the delicate balance between food supply and demand under growing natural resource scarcity. To estimate the potential impacts of "mega-droughts" on the water and food systems in the IGP, we develop worst-case drought scenarios through inverse modeling of tree-ring-based PDSI reconstruction that covers the period 1300-1899 (A.D.), and analyze these historic mega-drought scenarios using IFPRI's IMPACT global water and food projections model. The base year of the IMPACT model is parameterized using socioeconomic and engineering data that reflect today's water management and infrastructure, agricultural technologies, population, income, and market institutions. The base year simulation is validated against observations to ensure model fidelity. Anticipated changes of the above factors in the future out to 2050 are specified using demographic and economic growth projections and literature data. Model simulation results represent the consequences of mega-droughts in the IGP given technological and socioeconomic conditions of today and in the future. We also explore policy options for increasing the resilience of water and food systems in the IGP, through scenario

The effect of pH on the uptake and toxicity of the bivalent weak base chloroquine tested on Salix viminalis and Daphnia magna

DEFF Research Database (Denmark)

Rendal, Cecilie; Kusk, Kresten Ole; Trapp, Stefan

2011-01-01

, and therefore a higher toxicity can be expected. The current study examines the pHdependent toxicity and bioaccumulation of the bivalent weak base chloroquine (pKa: 10.47 and 6.33, log KOW 4.67) tested on Salix viminalis (basket willow) and Daphnia magna (water flea). The transpiration rates of hydroponically...

Mega-city and great earthquake distributions: the search of basic links.

Science.gov (United States)

Levin, Boris; Sasorova, Elena; Domanski, Andrej

2013-04-01

The ever-increasing population density in large metropolitan cities near major active faults (e.g. Tokyo, Lisbon, San-Francisco, et al.) and recent catastrophic earthquakes in Japan, Indonesia and Haiti (loss of life more 500000), highlight the need for searching of causal relationships between distributions of earthquake epicenters and mega-cities at the Earth [1]. The latitudinal distribution of mega-cities calculated with using Internet data base, discovers a curious peculiarity: the density of large city numbers, related to 10-degree latitude interval, demonstrates two maximums in middle latitudes (±30-40°) on both sides of the equator. These maximums are separated by clean local minimum near equator, and such objects (mega-cities) are practically absent in the high latitudes. In the last two decades, it was shown [2, 3, 4] that a seismic activity of the Earth is described by the similar bimodal latitudinal distribution. The similarity between bimodal distributions for geophysical phenomena and mega-city locations attracts common attention. The peak values in the both distributions (near ±35°) correspond to location of well-known "critical latitudes" at the planet. These latitudes were determined [5], as the lines of intersection of a sphere and a spheroid of equal volume (±35°15'52″). Increasing of the angular velocity of a celestial body rotation leads to growth of oblateness of planet, and vice versa, the oblateness is decreasing with reducing of velocity of rotation. So, well-known effect of the Earth rotation instability leads to small pulsations of the geoid. In the critical latitudes, the geoid radius-vector is equal to the radius of sphere. The zones of near critical latitudes are characterized by high density of faults in the Earth crust and manifestation of some geological peculiarities (hot spot distribution, large ore deposit distribution, et al.). The active faults existence has led to an emanation of depth fluids, which created the good

The bidding paradox : how economists and politicians might agree on the attractiveness of mega sports events

NARCIS (Netherlands)

van den Berg, Marcel; de Nooij, Michiel

The ambition to host mega sports events is (or can be) perfectly justifiable with various arguments. The most persistently used argument is the supposed financial or direct economic gain for the host economy, of which the compelling body of evidence is discouraging. This implies that the

Adding value to the decision-making process of mega projects : Fostering strategic ambiguity, redundancy, and resilience

NARCIS (Netherlands)

Giezen, Mendel; Salet, Willem; Bertolini, Luca

2015-01-01

Current practice in decision-making about mega projects seems to be aimed at reducing complexity by simplification. However, this is often detrimental to the resilience and added value of these projects. This article uses the concept of strategic capacity for analyzing the decision-making process on

Navigating mega projects through complexity and uncertainty: strategic and adaptive capacity in planning and decision-making

NARCIS (Netherlands)

Giezen, M.

2012-01-01

Over the last few decades, there has been an increasing interest in mega projects from both policy makers and academics. Of particular concern to both has been the seemingly structural time and cost overruns associated with these projects. In response a tendency, especially of policy makers, has

Magna Carta And Its Significant Role For Rule Of Law In The Republic Of Macedonia

Directory of Open Access Journals (Sweden)

Shumanovska-Spasovska Ivana

2015-12-01

Full Text Available One of the most important and famous historical documents from the English legal and constitutional legacy is the Magna Carta Libertatum. Signed and sealed in the year 1215 the Magna Carta is further on viewed as the sole inception of the idea of limiting the power of the ruler trough legal rules. That limitation is to be made with legal rules that are binding for everyone, even the monarch. Therefore, the Great Charter is viewed as the first document signed by a monarch with which, the principle of supremacy of the law is set out. That supremacy of the law has been further on developed by eminent scholars and practitioners, eventually leading to the development of the concept of rule of law. Rule of law, as a concept, means that the royal authority (or the executive branch of power is going to be inferior to the law. However, this concept means a lot more than simply that. Unlike the principle of legal state, the rule of law is closely linked to justice, separation of powers and legal certainty. All of these concepts are actually prerequisites for its existence. That is why each of them is separately examined and elaborated. Furthermore, as one of the most important principles the rule of law had a great influence on the constitutional (and legal systems around the world. Since the Republic of Macedonia strives to become a democratic state where the rule of law is established and developed it is important to elaborate the influence of this principle in it. Therefore, the research gravitates over the principle of rule of law in the Republic of Macedonia.

Aspectos raciais dos "megas" e da cardiopatia na doença de Chagas crônica

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Lineu José Miziara

1981-06-01

Full Text Available O estudo de 724 pacientes chagásicos crônicos mostrou que a insuficiência cardíaca congestiva é mais freqüente e de aparecimento mais precoce nos pacientes de raça negra do que nos brancos. A ocorrência de "megas" foi ligeiramente inferior nos chagásicos negros não sendo estatisticamente significativa a diferença observada. A maior freqüência de insuficiência cardíaca nos pretos parece estar relacionada a características biológicas do tecido conjuntivo que condicionam uma resposta fibrosante mais acentuada no miocârdio agredido pela Tripanossomose. Estas observações estariam de acordo com outros estudos sobre a doença de Chagas que admitem ser a denervação o fator mais importante para o aparecimento dos "megas" e a inflamação com fibrose miocârdica acentuada um elemento básico para explicar a insuficiência cardíaca.

Mega wildfire in the World Biosphere Reserve (UNESCO), Torres del Paine National Park, Patagonia - Chile 2012: Work experience in extreme behavior conditions in the context of global warming

Science.gov (United States)

René Cifuentes Medina

2013-01-01

Mega wildfires are critical, high-impact events that cause severe environmental, economic and social damage, resulting, in turn, in high-cost suppression operations and the need for mutual support, phased use of resources and the coordinated efforts of civilian government agencies, the armed forces, private companies and the international community. The mega forest...

Comparative evolutionary diversity and phylogenetic structure across multiple forest dynamics plots: a mega-phylogeny approach

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David Lee Erickson

2014-11-01

Full Text Available Forest dynamics plots, which now span longitudes, latitudes, and habitat types across the globe, offer unparalleled insights into the ecological and evolutionary processes that determine how species are assembled into communities. Understanding phylogenetic relationships among species in a community has become an important component of assessing assembly processes. However, the application of evolutionary information to questions in community ecology has been limited in large part by the lack of accurate estimates of phylogenetic relationships among individual species found within communities, and is particularly limiting in comparisons between communities. Therefore, streamlining and maximizing the information content of these community phylogenies is a priority. To test the viability and advantage of a multi-community phylogeny, we constructed a multi-plot mega-phylogeny of 1,347 species of trees across 15 forest dynamics plots in the ForestGEO network using DNA barcode sequence data (rbcL, matK and psbA-trnH and compared community phylogenies for each individual plot with respect to support for topology and branch lengths, which affect evolutionary inference of community processes. The levels of taxonomic differentiation across the phylogeny were examined by quantifying the frequency of resolved nodes throughout. In addition, three phylogenetic distance metrics that are commonly used to infer assembly processes were estimated for each plot (Phylogenetic Distance [PD], Mean Phylogenetic Distance [MPD], and Mean Nearest Taxon Distance [MNTD]. Lastly, we examine the partitioning of phylogenetic diversity among community plots through quantification of inter-community MPD and MNTD. Overall, evolutionary relationships were highly resolved across the DNA barcode-based mega-phylogeny, and phylogenetic resolution for each community plot was improved when estimated within the context of the mega-phylogeny. Likewise, when compared with phylogenies for

Câncer do esôfago em paciente com megaesôfago chagásico Esophageal cancer in patient with chagasic megaesophagus

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Maria Aparecida Coelho de Arruda Henry

2007-06-01

Full Text Available RACIONAL: O megaesôfago constitui problema de saúde pública em nosso país, pois acomete indivíduos em sua fase de maior produtividade. Os doentes com essa afecção podem apresentar em sua evolução associação com câncer do esôfago. OBJETIVO: Analisar os aspectos clínicos e epidemiológicos de pacientes com megaesôfago e câncer do esôfago. MÉTODOS: Foram avaliados de maneira retrospectiva 20 pacientes com megaesôfago e câncer (grupo 1 e 20 com câncer do esôfago (grupo 2. Estudaram-se os dados demográficos, hábitos (etilismo e tabagismo, tipo histológico do tumor, localização da lesão, diferenciação celular, estádio, tratamento e sobrevida. RESULTADOS: Não foi observada diferença entre os grupos, com relação à idade, sexo, localização da lesão, tipo histológico do tumor, diferenciação celular, estádio e sobrevida. Com relação aos hábitos de vida, a associação de etilismo e tabagismo foi observada em maior número de pacientes com câncer do esôfago sem o antecedente de megaesôfago. CONCLUSÃO: As características clínicas dos pacientes com megaesôfago e câncer não diferem daqueles com neoplasia maligna esofágica não associada ao megaesôfago, principalmente no que se refere ao prognóstico desfavorável frente ao tratamento instituído. Nos pacientes com megaesôfago o tumor pode se localizar em qualquer porção do órgão.BACKGROUND: Megaesophagus constitutes a public health problem in our country since it affects individuals in the most productive phase of their lives. During the development of the disease, people suffering from it may present association with esophageal cancer. AIM: To analyze the clinical and epidemiological aspects of patients with megaesophagus and esophageal cancer. METHODS: Twenty patients with megaesophagus and cancer (group 1 and 20 patients with esophageal cancer (group 2 were retrospectively analyzed. Demographic data, habits (alcoholism and smoking, tumor

Claudia Quinta (Pro Caelio 34 and an altar to Magna Mater

Directory of Open Access Journals (Sweden)

Eleanor Winsor Leach

2010-11-01

Full Text Available Among the items of sculpture from the Capitoline collection now housed in the Museum of the Power Station Montemartini is a marble relief altar of the Claudian Period (E. Simon's dating dedicated to the mater deorum and the navis salvia and depicting the arrival of the goddess Cybele at Rome by ship. The dedicator is one Claudia Syntyche and the sculpture alludes to the legends attached to a much honored woman of the Claudian family whom Cicero, in his oration pro Caelio brought on stage in a cameo appearance to bolster his case against the controversial contemporary woman Clodia Metelli as one of the accusers of his client M. Caelius Rufus. This paper will consider questions raised by the iconography of the altar with reference to the development of Claudia's legend in Roman mythology and subsequently ask who was this Claudia the dedicator and why did she choose Magna Mater for her vow?

[A review of the firefighting techniques used on the tanker 'Mega Borg' explosion

International Nuclear Information System (INIS)

Driscoll, J.

1992-01-01

This paper reviews the events leading up to the explosion and fire of the Mega Borg, a Norwegian tanker which exploded in the Gulf of Mexico in June of 1990. It briefly discusses the fire fighting strategy used to cool the ship prior to foam application and the types of equipment used. It also briefly discusses the lightering operation and the cargo recovery and dewatering operations which took place after the fire was extinguished

Validation of a Mathematical Model for Green Algae (Raphidocelis Subcapitata Growth and Implications for a Coupled Dynamical System with Daphnia Magna

Directory of Open Access Journals (Sweden)

Michael Stemkovski

2016-05-01

Full Text Available Toxicity testing in populations probes for responses in demographic variables to anthropogenic or natural chemical changes in the environment. Importantly, these tests are primarily performed on species in isolation of adjacent tropic levels in their ecosystem. The development and validation of coupled species models may aid in predicting adverse outcomes at the ecosystems level. Here, we aim to validate a model for the population dynamics of the green algae Raphidocelis subcapitata, a planktonic species that is often used as a primary food source in toxicity experiments for the fresh water crustacean Daphnia magna. We collected longitudinal data from three replicate population experiments of R. subcapitata. We used this data with statistical model comparison tests and uncertainty quantification techniques to compare the performance of four models: the Logistic model, the Bernoulli model, the Gompertz model, and a discretization of the Logistic model. Overall, our results suggest that the logistic model is the most accurate continuous model for R. subcapitata population growth. We then implement the numerical discretization showing how the continuous logistic model for algae can be coupled to a previously validated discrete-time population model for D. magna.

Rupture process of the 2013 Okhotsk deep mega earthquake from iterative backprojection and compress sensing methods

Science.gov (United States)

Qin, W.; Yin, J.; Yao, H.

2013-12-01

On May 24th 2013 a Mw 8.3 normal faulting earthquake occurred at a depth of approximately 600 km beneath the sea of Okhotsk, Russia. It is a rare mega earthquake that ever occurred at such a great depth. We use the time-domain iterative backprojection (IBP) method [1] and also the frequency-domain compressive sensing (CS) technique[2] to investigate the rupture process and energy radiation of this mega earthquake. We currently use the teleseismic P-wave data from about 350 stations of USArray. IBP is an improved method of the traditional backprojection method, which more accurately locates subevents (energy burst) during earthquake rupture and determines the rupture speeds. The total rupture duration of this earthquake is about 35 s with a nearly N-S rupture direction. We find that the rupture is bilateral in the beginning 15 seconds with slow rupture speeds: about 2.5km/s for the northward rupture and about 2 km/s for the southward rupture. After that, the northward rupture stopped while the rupture towards south continued. The average southward rupture speed between 20-35 s is approximately 5 km/s, lower than the shear wave speed (about 5.5 km/s) at the hypocenter depth. The total rupture length is about 140km, in a nearly N-S direction, with a southward rupture length about 100 km and a northward rupture length about 40 km. We also use the CS method, a sparse source inversion technique, to study the frequency-dependent seismic radiation of this mega earthquake. We observe clear along-strike frequency dependence of the spatial and temporal distribution of seismic radiation and rupture process. The results from both methods are generally similar. In the next step, we'll use data from dense arrays in southwest China and also global stations for further analysis in order to more comprehensively study the rupture process of this deep mega earthquake. Reference [1] Yao H, Shearer P M, Gerstoft P. Subevent location and rupture imaging using iterative backprojection for

Potential climatic mechanisms associated with the mega drought at 4200 cal yr BP: linking proxy data with modern climate analogues

Science.gov (United States)

Carter, V.; Shinker, J. J.

2017-12-01

Roughly 4200 years ago, a 150-year long mega drought occurred in the central Rocky Mountains, as indicated by pollen evidence from lake sediments from Long Lake, south-eastern Wyoming. However, pollen evidence does not record the climate mechanisms that caused the drought; they only provide evidence that the drought occurred. A modern climate analogue technique using North American Regional Reanalysis data was applied to the sedimentary data in order to identify possible synoptic and dynamic patterns that may have caused the mega drought at 4200 cal yr BP. Our results suggest warm and dry conditions were a result of anomalously higher-than-normal geopotential heights that were centred over the Great Plains beginning in the spring and persisting through the fall. Drought conditions during the growing seasons was the result of the anomalous high-pressure ridge, which suppressed moisture transport via the low level jet from the Gulf of Mexico, as well as brought in dry continental air from in the interior region of North America. The conditions associated with modern analogues offer a potential climate mechanism that caused the mega drought 4200 years ago, and likely led to the changes in vegetation composition as evidenced by the pollen record from Long Lake, Wyoming.

Upgrade of the TAMU MDM-focal plane detector with MicroMegas technology

Energy Technology Data Exchange (ETDEWEB)

Spiridon, A., E-mail: aspiridon@comp.tamu.edu [Cyclotron Institute, Texas A& M University, College Station, TX 77843 (United States); Pollacco, E. [IRFU, CEA Saclay, Gif-sur-Yvette (France); Roeder, B.T.; Saastamoinen, A.; Chyzh, R.; Dag, M.; Tribble, R.E. [Cyclotron Institute, Texas A& M University, College Station, TX 77843 (United States); Trache, L.; Pascovici, G. [National Institute of Physics and Nuclear Engineering, Bucharest-Magurele RO-077125 (Romania); De Oliveira, R. [CERN, Geneva (Switzerland)

2016-06-01

A gridded ionization chamber used as a focal plane detector at the back of the TAMU-MDM spectrometer was modified to use MicroMegas technology for the purpose of improving energy resolution and particle identification. The upgraded system was tested in experimental conditions with several heavy-ion beams at 12 MeV/u and found to achieve resolutions between 3.2% and 4.8%. This is a significant improvement over the previous performance of 10–15% obtained using the existing, conventional ionization chambers.

Upgrade of the TAMU MDM-focal plane detector with MicroMegas technology

International Nuclear Information System (INIS)

Spiridon, A.; Pollacco, E.; Roeder, B.T.; Saastamoinen, A.; Chyzh, R.; Dag, M.; Tribble, R.E.; Trache, L.; Pascovici, G.; De Oliveira, R.

2016-01-01

A gridded ionization chamber used as a focal plane detector at the back of the TAMU-MDM spectrometer was modified to use MicroMegas technology for the purpose of improving energy resolution and particle identification. The upgraded system was tested in experimental conditions with several heavy-ion beams at 12 MeV/u and found to achieve resolutions between 3.2% and 4.8%. This is a significant improvement over the previous performance of 10–15% obtained using the existing, conventional ionization chambers.

Acute toxicity tests with Daphnia magna, Americamysis bahia, Chironomus riparius and Gammarus pulex and implications of new EU requirenments for the aquatic effect assessment of insecticides

NARCIS (Netherlands)

Brock, T.C.M.; Wijngaarden, van R.P.A.

2012-01-01

Threshold concentrations for treatment related effects of 31 insecticides, as derived from aquatic micro-/mesocosm tests, were used to calibrate the predictive value of the European Tier-1 acute effect assessment on basis of laboratory toxicity tests with Daphnia magna, Chironomus spp., Americamysis

Responsiveness to a Prospective Student E-Mail Inquiry by Community Colleges in the Nine Mega-States

Science.gov (United States)

Shadinger, David A.

2014-01-01

This quantitative study investigated e-mail responsiveness by community colleges in the nine mega-states to an inquiry from a prospective student. Noel-Levitz (2006b) reported that prospective students want to receive an e-mail with information about an institution prior to applying for admission. Specifically, high school juniors and seniors want…

Integrated analysis of the ecotoxicological and genotoxic effects of the antimicrobial peptide melittin on Daphnia magna and Pseudokirchneriella subcapitata

International Nuclear Information System (INIS)

Galdiero, Emilia; Maselli, Valeria; Falanga, Annarita; Gesuele, Renato; Galdiero, Stefania; Fulgione, Domenico; Guida, Marco

2015-01-01

Melittin is a major constituent of the bee venom of Apis mellifera with a broad spectrum of activities. Melittin therapeutical potential is subject to its toxicity and the assessment of ecotoxicity and genotoxicity is of particular interest for therapeutic use. Here we analyzed the biological effects of melittin on two aquatic species, which are representative of two different levels of the aquatic trophic chain: the invertebrate Daphnia magna and the unicellular microalgae Pseudokirchneriella subcapitata. The attention was focused on the determination of: i) ecotoxicity; ii) genotoxicity; iii) antigenotoxicity. Our main finding is that melittin is detrimental to D. magna reproduction and its sub-lethal concentrations create an accumulation dependent on exposition times and a negative effect on DNA. We also observed that melittin significantly delayed time to first eggs. Moreover, results showed that melittin exerted its toxic and genotoxic effects in both species, being a bit more aggressive towards P. subcapitata. - Highlights: • We examine ecotoxicity to study how AMPs affect the environment. • We examine genotoxicity in order to analyze the damages to the DNA. • We examine the antigenotoxicity in order to verify DNA repair ability of the cells. • Possible therapeutical applications of AMPs depend on assessment of ecotoxicity. - Melittin exerts its dose dependent toxic and genotoxic effects on both indicators; no toxicity is found at concentrations that may typically reach the environment

Sustainable innovation in intensive animal husbandry; policy and public protests towards a mega-farm in the Netherlands.

NARCIS (Netherlands)

Horlings, L.G.; Hinssen, J.P.P.

2014-01-01

In this paper the planning and implementation of a specific mega-farm in the Netherlands is discussed, the so called ‘New Mixed Business’ (NMB). The central question is: how did communication, contestation and controversies play a role in the implementation of this innovative concept for sustainable

StegNet: Mega Image Steganography Capacity with Deep Convolutional Network

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Pin Wu

2018-06-01

Full Text Available Traditional image steganography often leans interests towards safely embedding hidden information into cover images with payload capacity almost neglected. This paper combines recent deep convolutional neural network methods with image-into-image steganography. It successfully hides the same size images with a decoding rate of 98.2% or bpp (bits per pixel of 23.57 by changing only 0.76% of the cover image on average. Our method directly learns end-to-end mappings between the cover image and the embedded image and between the hidden image and the decoded image. We further show that our embedded image, while with mega payload capacity, is still robust to statistical analysis.

Tsunami simulations of mega-thrust earthquakes in the Nankai–Tonankai Trough (Japan) based on stochastic rupture scenarios

KAUST Repository

Goda, Katsuichiro

2017-02-23

In this study, earthquake rupture models for future mega-thrust earthquakes in the Nankai–Tonankai subduction zone are developed by incorporating the main characteristics of inverted source models of the 2011 Tohoku earthquake. These scenario ruptures also account for key features of the national tsunami source model for the Nankai–Tonankai earthquake by the Central Disaster Management Council of the Japanese Government. The source models capture a wide range of realistic slip distributions and kinematic rupture processes, reflecting the current best understanding of what may happen due to a future mega-earthquake in the Nankai–Tonankai Trough, and therefore are useful for conducting probabilistic tsunami hazard and risk analysis. A large suite of scenario rupture models is then used to investigate the variability of tsunami effects in coastal areas, such as offshore tsunami wave heights and onshore inundation depths, due to realistic variations in source characteristics. Such investigations are particularly valuable for tsunami hazard mapping and evacuation planning in municipalities along the Nankai–Tonankai coast.

Combined acute ecotoxicity of malathion and deltamethrin to Daphnia magna (Crustacea, Cladocera): comparison of different data analysis approaches.

Science.gov (United States)

Toumi, Héla; Boumaiza, Moncef; Millet, Maurice; Radetski, Claudemir Marcos; Camara, Baba Issa; Felten, Vincent; Masfaraud, Jean-François; Férard, Jean-François

2018-04-19

We studied the combined acute effect (i.e., after 48 h) of deltamethrin (a pyrethroid insecticide) and malathion (an organophosphate insecticide) on Daphnia magna. Two approaches were used to examine the potential interaction effects of eight mixtures of deltamethrin and malathion: (i) calculation of mixture toxicity index (MTI) and safety factor index (SFI) and (ii) response surface methodology coupled with isobole-based statistical model (using generalized linear model). According to the calculation of MTI and SFI, one tested mixture was found additive while the two other tested mixtures were found no additive (MTI) or antagonistic (SFI), but these differences between index responses are only due to differences in terminology related to these two indexes. Through the surface response approach and isobologram analysis, we concluded that there was a significant antagonistic effect of the binary mixtures of deltamethrin and malathion that occurs on D. magna immobilization, after 48 h of exposure. Index approaches and surface response approach with isobologram analysis are complementary. Calculation of mixture toxicity index and safety factor index allows identifying punctually the type of interaction for several tested mixtures, while the surface response approach with isobologram analysis integrates all the data providing a global outcome about the type of interactive effect. Only the surface response approach and isobologram analysis allowed the statistical assessment of the ecotoxicological interaction. Nevertheless, we recommend the use of both approaches (i) to identify the combined effects of contaminants and (ii) to improve risk assessment and environmental management.

Interclonal proteomic responses to predator exposure in Daphnia magna may depend on predator composition of habitats.

Science.gov (United States)

Otte, Kathrin A; Schrank, Isabella; Fröhlich, Thomas; Arnold, Georg J; Laforsch, Christian

2015-08-01

Phenotypic plasticity, the ability of one genotype to express different phenotypes in response to changing environmental conditions, is one of the most common phenomena characterizing the living world and is not only relevant for the ecology but also for the evolution of species. Daphnia, the water flea, is a textbook example for predator-induced phenotypic plastic defences; however, the analysis of molecular mechanisms underlying these inducible defences is still in its early stages. We exposed Daphnia magna to chemical cues of the predator Triops cancriformis to identify key processes underlying plastic defensive trait formation. To get a more comprehensive idea of this phenomenon, we studied four genotypes with five biological replicates each, originating from habitats characterized by different predator composition, ranging from predator-free habitats to habitats containing T. cancriformis. We analysed the morphologies as well as proteomes of predator-exposed and control animals. Three genotypes showed morphological changes when the predator was present. Using a high-throughput proteomics approach, we found 294 proteins which were significantly altered in their abundance after predator exposure in a general or genotype-dependent manner. Proteins connected to genotype-dependent responses were related to the cuticle, protein synthesis and calcium binding, whereas the yolk protein vitellogenin increased in abundance in all genotypes, indicating their involvement in a more general response. Furthermore, genotype-dependent responses at the proteome level were most distinct for the only genotype that shares its habitat with Triops. Altogether, our study provides new insights concerning genotype-dependent and general molecular processes involved in predator-induced phenotypic plasticity in D. magna. © 2015 John Wiley & Sons Ltd.

Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: comparing meta and mega analytical approaches for data pooling

Science.gov (United States)

Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E.; Mandl, René C.; Almasy, Laura; Booth, Tom; Brouwer, Rachel M.; Curran, Joanne E.; de Zubicaray, Greig I.; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T.; Hong, L. Elliot; Landman, Bennett A.; Lemaitre, Hervé; Lopez, Lorna; Martin, Nicholas G.; McMahon, Katie L.; Mitchell, Braxton D.; Olvera, Rene L.; Peterson, Charles P.; Starr, John M.; Sussmann, Jessika E.; Toga, Arthur W.; Wardlaw, Joanna M.; Wright, Margaret J.; Wright, Susan N.; Bastin, Mark E.; McIntosh, Andrew M.; Boomsma, Dorret I.; Kahn, René S.; den Braber, Anouk; de Geus, Eco JC; Deary, Ian J.; Hulshoff Pol, Hilleke E.; Williamson, Douglas E.; Blangero, John; van ’t Ent, Dennis; Thompson, Paul M.; Glahn, David C.

2014-01-01

Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9–85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large “mega-family”. We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. PMID:24657781

Mixture toxicity of flubendazole and fenbendazole to Daphnia magna.

Science.gov (United States)

Puckowski, Alan; Stolte, Stefan; Wagil, Marta; Markiewicz, Marta; Łukaszewicz, Paulina; Stepnowski, Piotr; Białk-Bielińska, Anna

2017-05-01

Nowadays, residual amounts of many pharmaceuticals can be found in various environmental compartments including surface and ground waters, soils and sediments as well as biota. Even though they undergo degradability, their environmental discharge is relatively continuous, thus they may be regarded as quasi-persistent contaminants, and are also frequently regarded as emerging organic pollutants. Benzimidazoles, especially flubendazole (FLU) and fenbendazole (FEN), represent two anthelmintic drugs belonging to this group. Although their presence in environmental matrices has been reported, there is relatively little data concerning their (eco)toxicological impact. Furthermore, no data is available on their mixture toxicity. FLU and FEN have been found to have a strong impact on an environmentally important non-target organism - Daphnia magna. Moreover, these compounds are usually present in the environment as a part of pharmaceutical mixtures. Therefore, there is a need to evaluate their mixture toxicity, which was the main aim of this study. Single substance toxicity tests were carried out in parallel with mixture studies of FLU and FEN, with the application of two well established concepts of Concentration Addition (CA) and Independent Action (IA). As a result, both models (CA and IA) were found to underestimate the toxicity of mixtures, however CA yielded more accurate predictions. Copyright © 2017 Elsevier GmbH. All rights reserved.

Análisis general del mega-deslizamiento Ortiga-Potrerillos, Acosta, San José, Costa Rica

Directory of Open Access Journals (Sweden)

Madrigal Mora, Julio

2011-12-01

Full Text Available El artículo ofrece un acercamiento a los antecedentes y características del mega-deslizamiento Ortiga-Potrerillos, producido en el cantón de Acosta. Realiza una descripción general de la amenaza y la vulnerabilidad de la zona, desde un enfoque mayormente geológico. Identifica algunos de los problemas suscitados en el sitio del deslizamiento. Proporciona un análisis de la condición de la ruta 209, que une las comunidades Aserrí - Acosta y la cual se ve afectada por las condiciones del terreno. Por último, presenta unas observaciones finales a modo de conclusiones The article approaches the background and characteristics of the mega-landslide at Ortiga-Potrerillos, in Acosta. It provides a general description of the threat and vulnerability of the zone, mainly from a geological focus. It identifies some of the problems generated in the area due to the landslide. It provides an analysis in the condition of route 209, that unites the communities of Aserrí - Acosta and that is affected by the terrain conditions. Lastly, it presents final observations as conclusions

Glymphatic clearance controls state-dependent changes in brain lactate concentration

DEFF Research Database (Denmark)

Lundgaard, Iben; Lu, Minh Lon; Yang, Ezra

2017-01-01

Brain lactate concentration is higher during wakefulness than in sleep. However, it is unknown why arousal is linked to an increase in brain lactate and why lactate declines within minutes of sleep. Here, we show that the glymphatic system is responsible for state-dependent changes in brain lacta......-lymphatic clearance. This analysis provides fundamental new insight into brain energy metabolism by demonstrating that glucose that is not fully oxidized can be exported as lactate via glymphatic-lymphatic fluid transport.......Brain lactate concentration is higher during wakefulness than in sleep. However, it is unknown why arousal is linked to an increase in brain lactate and why lactate declines within minutes of sleep. Here, we show that the glymphatic system is responsible for state-dependent changes in brain lactate...... concentration. Suppression of glymphatic function via acetazolamide treatment, cisterna magna puncture, aquaporin 4 deletion, or changes in body position reduced the decline in brain lactate normally observed when awake mice transition into sleep or anesthesia. Concurrently, the same manipulations diminished...

Comparison between EEG and observation of rabbit behaviour in evaluation of subarachnoid neurotoxicity of metrizamide

International Nuclear Information System (INIS)

Maly, P.; Elmqvist, D.; Almen, T.; Golman, K.; Lund Univ. Hospital; Nyegaard and Co. A/S, Oslo

1986-01-01

The non-ionic contrast medium metrizamide (370 mg I/ml) was injected into the cisterna magna of rabbits at 2 dose levels (0.1 ml/kg and 0.5 ml/kg) to investigate whether visually evaluated EEG can detect neutrotoxicity at a lower dose level than a method based on observation and ranking of signs of excitation and depression in animal behaviour. Half of the metrizamide injections were made without anaesthesia, whereas the remaining injections were made during a short alphadolon/alphaxolon anaesthesia. EEG and animal behaviour were followed for 24 h after the injection of metrizamide. At the low 'clinical' dose, EEG could not detect statistically significant neurotoxicity, neither in anaesthetized nor in non-anaesthetized rabbits. Observation of animal behaviour, however, could detect statistically significant signs of depression in animals that had been anaesthetized. At the high dose level, both methods could detect significantly more serious symptoms of neurotoxicity than at the low dose level. (orig.)

An Improved Method for Collection of Cerebrospinal Fluid from Anesthetized Mice

DEFF Research Database (Denmark)

Lim, Nastasia K-H; Moestrup, Visse Theresia Skov; Zhang, Xiao

2017-01-01

a technique that improves on current methods of collection to minimize contamination from blood and allow for the abundant collection of CSF (on average 10-15 µL can be collected). This technique can be used with other dissection methods for tissue collection from mice, as it does not impact any tissues......The cerebrospinal fluid (CSF) is a valuable body fluid for analysis in neuroscience research. It is one of the fluids in closest contact with the central nervous system and thus, can be used to analyze the diseased state of the brain or spinal cord without directly accessing these tissues. However......, in mice it is difficult to obtain from the cisterna magna due to its closeness to blood vessels, which often contaminate samples. The area for CSF collection in mice is also difficult to dissect to and often only small samples are obtained (maximum of 5-7 µL or less). This protocol describes in detail...

Glymphatic clearance controls state-dependent changes in brain lactate concentration.

Science.gov (United States)

Lundgaard, Iben; Lu, Minh Lon; Yang, Ezra; Peng, Weiguo; Mestre, Humberto; Hitomi, Emi; Deane, Rashid; Nedergaard, Maiken

2017-06-01

Brain lactate concentration is higher during wakefulness than in sleep. However, it is unknown why arousal is linked to an increase in brain lactate and why lactate declines within minutes of sleep. Here, we show that the glymphatic system is responsible for state-dependent changes in brain lactate concentration. Suppression of glymphatic function via acetazolamide treatment, cisterna magna puncture, aquaporin 4 deletion, or changes in body position reduced the decline in brain lactate normally observed when awake mice transition into sleep or anesthesia. Concurrently, the same manipulations diminished accumulation of lactate in cervical, but not in inguinal lymph nodes when mice were anesthetized. Thus, our study suggests that brain lactate is an excellent biomarker of the sleep-wake cycle and increases further during sleep deprivation, because brain lactate is inversely correlated with glymphatic-lymphatic clearance. This analysis provides fundamental new insight into brain energy metabolism by demonstrating that glucose that is not fully oxidized can be exported as lactate via glymphatic-lymphatic fluid transport.

Analysis of the swimming velocity of cadmium-stressed Daphnia magna

International Nuclear Information System (INIS)

Baillieul, M.; Blust, R.

1999-01-01

The swimming velocity of the waterflea Daphnia magna is dependent on its body size. Therefore, environmental factors like toxic stress that influence growth also influence swimming velocity. An experiment was set up to test whether exposure to cadmium would reduce only growth, with a concomitant decrease in velocity, or whether it would reduce velocity below the swimming velocity of similarly-sized control animals. Daphnids were exposed for 10 days to free cadmium ion concentrations ranging from 1x10 -8 to 1x10 -7 M Cd 2+ , and body size and swimming velocity were measured every 2 days. The results showed that cadmium decreased both growth and velocity, i.e. exposed daphnids swam slower than similarly-sized control daphnids. Swimming velocity provided no indication of successful acclimation in any cadmium treatment. Food consumption and assimilation were reduced by exposure to cadmium. This reduced food intake may have, at least partially, caused the decreased growth rates. However, since reduced food intake does not affect swimming velocity, the reduced swimming velocity must be attributed to toxic effects of cadmium, other than those on food intake. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Finding ultracool brown dwarfs with MegaCam on CFHT: method and first results

Science.gov (United States)

Delorme, P.; Willott, C. J.; Forveille, T.; Delfosse, X.; Reylé, C.; Bertin, E.; Albert, L.; Artigau, E.; Robin, A. C.; Allard, F.; Doyon, R.; Hill, G. J.

2008-06-01

Aims: We present the first results of a wide field survey for cool brown dwarfs with the MegaCam camera on the CFHT telescope, the Canada-France Brown Dwarf Survey, hereafter CFBDS. Our objectives are to find ultracool brown dwarfs and to constrain the field-brown dwarf mass function thanks to a larger sample of L and T dwarfs. Methods: We identify candidates in CFHT/MegaCam i' and z' images using optimised psf-fitting within Source Extractor, and follow them up with pointed near-infrared imaging on several telescopes. Results: We have so far analysed over 350 square degrees and found 770 brown dwarf candidates brighter than z'_AB=22.5. We currently have J-band photometry for 220 of these candidates, which confirms 37% as potential L or T dwarfs. Some are among the reddest and farthest brown dwarfs currently known, including an independent identification of the recently published ULAS J003402.77-005206.7 and the discovery of a second brown dwarf later than T8, CFBDS J005910.83-011401.3. Infrared spectra of three T dwarf candidates confirm their nature, and validate the selection process. Conclusions: The completed survey will discover ~100 T dwarfs and ~500 L dwarfs or M dwarfs later than M8, approximately doubling the number of currently known brown dwarfs. The resulting sample will have a very well-defined selection function, and will therefore produce a very clean luminosity function. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. Based on observations made

La Preparación de un mega evento: El mundial de fútbol FIFA 2014 en Brasil

OpenAIRE

Formaggio Patricio, Raquel

2014-01-01

Este trabajo pretende investigar como Brasil, un país que en los últimos años ha crecido a nivel económico, social y cultural, está planificando, en el ámbito del Turismo, la organización de un mega evento deportivo: El Mundial de Futbol FIFA 2014

Uso eficiente da água de chuva armazenada em cisterna para produção de hortaliças no Semiárido pernambucano

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Elvis Pantaleão Ferreira

2016-04-01

Full Text Available O Semiárido brasileiro requer uma particular atenção, dada à irregularidade das precipitações pluviométricas que ocorrem na a região. A cisterna tipo Calçadão do programa Uma Terra e Duas Águas – P1+2 assegura melhoria na dieta alimentar das famílias rurais, por permitir a inserção de alimentação. Com o presente trabalho objetivou-se avaliar o uso eficiente da água empregada sob diferentes lâminas durante todo o ano de 2014, visando a produção de hortaliças no Semiárido pernambucano, com água de chuva armazenada em cisterna do P1+2. Para tanto, foram construídos dois canteiros, denominados 1 e 2, cada um com área de 4 m2, para produção de hortaliças, sendo aplicadas, respectivamente, lâminas de 8 mm dia-1 e 4 mm dia-1, durante todo o ano. Á água foi aplicada de forma manual, utilizando-se regador plástico. A melhor relação água/produção foi obtida com a aplicação de uma lâmina de 4 mm dia-1, suficiente para proporcionar o consumo diário de 33,71 gramas de hortaliças na alimentação de uma família.Efficient use of stored rain water in cistern to vegetable production in Semiarid pernambucanoAbstract: The Brazilian semiarid requires particular attention, given the irregularity of rainfall occurring in the region. The cistern program One Land and Two Waters - P1 + 2 ensures improvement in the diet of rural families by allowing the power input. The present study aimed to evaluate the efficiency of water used in different depths throughout the year 2014, aimed at producing vegetables in Pernambuco semiarid, with rainwater stored in cistern of P1 + 2. For this were constructed, two bed, called 1 and 2, each with an area of 4 m2 for vegetable production, and were applied, respectively, 8 mm blades day 1 and 4 mm Day-1 during the whole year. The water was applied manually, using plastic watering. The best result water/production was obtained with the application of a lamina 4 mm per day, sufficient to provide

Mega-mining in Mexico. Structural reforms and resistance

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Darcy Tetreault

2013-11-01

Full Text Available This article analyzes the structural causes of social environmental conflicts around mega-mining in Mexico and describes the emergence and coordination of resistance movements. It argues that neoliberal reforms have facilitated ‘accumulation by dispossession’ on two levels: first, by transferring public resources in the form of mineral reserves and state-run mining companies to the private sector; and second, bydispossessing smallholder farmers and indigenous communities of their land, water and cultural landscapes, in order to allow mining companies to carry out their activities. Furthermore, it argues that some factions of the resistance movements reflect ‘the environmentalism of the poor’ insofar as they seek to maintain natural resources outside of the sphere of the capitalist mode of production. Through a systematic revision of newspaper articles, blogs and scholarly publications, 29 high-profile eco-territorial mining conflicts are identified and a preliminary analysis of these is provided.

Bilateral cartilage T2 mapping 9 years after Mega-OATS implantation at the knee: a quantitative 3T MRI study.

Science.gov (United States)

Jungmann, P M; Brucker, P U; Baum, T; Link, T M; Foerschner, F; Minzlaff, P; Banke, I J; Saier, T; Imhoff, A B; Rummeny, E J; Bauer, J S

2015-12-01

To evaluate morphological and quantitative MR findings 9 years after autograft transfer of the posterior femoral condyle (Mega-OATS) and to correlate these findings with clinical outcomes. Quantitative MR measurements were also obtained of the contralateral knee and the utility as reference standard was investigated. Both knees of 20 patients with Mega-OATS osteochondral repair at the medial femoral condyle (MFC) were studied using 3T MRI 9 years after the procedure. MR-sequences included morphological sequences and a 2D multislice multiecho (MSME) spin echo (SE) sequence for quantitative cartilage T2 mapping. Cartilage segmentation was performed at the cartilage repair site and six additional knee compartments. Semi-quantitative MR observation of cartilage repair tissue (MOCART) scores and clinical Lysholm scores were obtained. Paired t-tests and Spearman correlations were used for statistical analysis. Global T2-values were significantly higher at ipsilateral knees compared to contralateral knees (42.1 ± 3.0 ms vs 40.4 ± 2.6 ms, P = 0.018). T2-values of the Mega-OATS site correlated significantly with MOCART scores (R = -0.64, P = 0.006). The correlations between MOCART and Lysholm scores and between absolute T2-values and Lysholm scores were not significant (P > 0.05). However, higher T2 side-to-side differences at the femoral condyles correlated significantly with more severe clinical symptoms (medial, R = -0.53, P = 0.030; lateral, R = -0.51, P = 0.038). Despite long-term survival, 9 years after Mega-OATS procedures, T2-values of the grafts were increased compared to contralateral knees. Clinical scores correlated best with T2 side-to-side differences of the femoral condyles, indicating that intraindividual adjustment may be beneficial for outcome evaluation. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

High concentrations of protein test substances may have non-toxic effects on Daphnia magna: implications for regulatory study designs and ecological risk assessments for GM crops.

Science.gov (United States)

Raybould, Alan; Burns, Andrea; Hamer, Mick

2014-01-01

Laboratory testing for possible adverse effects of insecticidal proteins on non-target organisms (NTOs) is an important part of many ecological risk assessments for regulatory decision-making about the cultivation of insect-resistant genetically modified (IRGM) crops. To increase confidence in the risk assessments, regulatory guidelines for effects testing specify that representative surrogate species for NTOs are exposed to concentrations of insecticidal proteins that are in excess of worst-case predicted exposures in the field. High concentrations in effects tests are achieved by using protein test substances produced in microbes, such as Escherichia coli. In a study that exposed Daphnia magna to a single high concentration of a microbial test substance containing Vip3Aa20, the insecticidal protein in MIR162 maize, small reductions in growth were observed. These effects were surprising as many other studies strongly suggest that the activity of Vip3Aa20 is limited to Lepidoptera. A plausible explanation for the effect on growth is that high concentrations of test substance have a non-toxic effect on Daphnia, perhaps by reducing its feeding rate. A follow-up study tested that hypothesis by exposing D. magna to several concentrations of Vip3Aa20, and a high concentration of a non-toxic protein, bovine serum albumin (BSA). Vip3Aa20 and BSA had sporadic effects on the reproduction and growth of D. magna. The pattern of the effects suggests that they result from non-toxic effects of high concentrations of protein, and not from toxicity. The implications of these results for regulatory NTO effects testing and ERA of IRGM crops are discussed.

Arduino Mega 2560 Microcontroller Built 3-Phase Seven Level Inverter

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PAVANKUMAR Shriram Mehtre

2017-10-01

Full Text Available n this paper, the implementation of 3-phase seven level cascaded H-bridge inverter is discussed with Arduino microcontroller and harmonic analysis is performed using Fourier series. The multilevel inverters (MLI give several benefits as reduced switching voltage stresses and the capability to operate in higher level voltage applications. A new and simple architecture Arduino Mega 2560 microcontroller is employed to produce the control signals for the seven level cascaded H-bridge MLI switches. The computer simulation is carried out in PSIM environment and prototype experimental model is developed with TLP 250 driver ICs and power MOSFET switches to validate the simulation results. The THDs present in different voltage level inverters are mathematically analysed using Fourier series.

Locked on course: Hydro-Quebec's commitment to mega-projects

International Nuclear Information System (INIS)

Maxwell, J.; Briscoe, F.; Suzuki, Tatsujiro; Lee, J.; Stewart, A.

1997-01-01

Large organizations often escalate their commitments to mega-project development, even after evidence becomes available of adverse environmental consequences or lack of economic feasibility. This escalation of commitment transcends both sectorial and national boundaries. Preeminent examples include controversial nuclear projects in the US, hydroelectric projects like the Three Gorges Dam in China, and transport projects like the Chunnel and the Concorde. In this article, the authors examine the experience of Hydro-Quebec with the Great Whale Project. They argue that Hydro-Quebec escalated its commitment even after serious questions emerged about its environmental impacts and economic feasibility, because of (1) its earlier success with large projects, (2) its engineering culture''s norms for consistency, and (3) its role in the government''s desire for economic and cultural autonomy. Finally, they discuss the changes that are necessary to break commitments to such projects

Test results from the MEGA experiment: A search for the rare decay of the muon to an electron and a gamma ray

International Nuclear Information System (INIS)

Jui, C.C.H.

1992-06-01

This thesis reports on recent progress of the MEGA experiment. MEGA is the latest in a series of muon decay experiments at the Los Alamos Meson Physics Facility. The primary goal of the group is to look for the lepton family number violating decay mode of μ + → e + γ with a branching ratio sensitivity of 3 x 10 -13 . The experiment employs an innovative two-arm magnetic spectrometer, where photons are converted into e + e - pairs within thin sheets of lead. This design maximizes rate capability, retains large solid angle, and suppresses the background to below experimental sensitivity. Both arms of the MEGA detector are state-of-the-art in design. The high-rate, low mass cylindrical MWPCs used in the positron arm are especially challenging. The fabrication of these chambers required many technical innovations, including precision-machined ceramic spacers, thin, inflatable cathode foils, and circular garlands made from annealed glass fibers. After several years of detector development, MEGA conducted a test run in 1990, where prototypes of various detector components were successfully tested in beam. A trial μ → eγ search was also conducted. Results from the positron chamber tests verified performance expectations in most respects. Within the limits of the tests, position and momentum resolutions are in good agreement with Monte Carlo simulations. The trial eγ search provided a much needed opportunity to test the detector system as a whole. No serious problems were uncovered in the search, which reached a sensitivity of 2.3 x 10 -7 in less than a day's running with an incomplete detector system severely limited in acceptance and efficiency. From these results, it is projected that a sensitivity of 5 x 10 -12 will be reached in 1992, to be improved to 3 x 10 -13 in 1993--94

Malaysian Mega Science Framework: The Need for Social Impact and Sustainability Assessment

Directory of Open Access Journals (Sweden)

Ahmad Zainal A.

2015-01-01

Full Text Available This review focuses on issues surrounding wastewater management as part of the National Sustainable Development (2013-2050 under the Malaysian Mega Science Framework. In line with the national priority area of water security, this review will highlight the technical reports compiled by the Academy of Sciences Malaysia (ASM on the challenges of water resource development and wastewater management and treatment. The discussion will dwell on the social impact of pollution in water and wastewater and mitigation plans that need to be put in place to ensure sustainable national development and making water as a National Key Economic Area (NKEA.

Environmental labeling of car tires--toxicity to Daphnia magna can be used as a screening method.

Science.gov (United States)

Wik, Anna; Dave, Göran

2005-02-01

Car tires contain several water-soluble compounds that can leach into water and have toxic effects on aquatic organisms. Due to tire wear, 10,000 tonnes of rubber particles end up along the Swedish roads every year. This leads to a diffuse input of emissions of several compounds. Emissions of polyaromatic hydrocarbons (PAHs) are of particular concern. PAHs are ingredients of the high aromatic oil (HA oil) that is used in the rubber as a softener and as a filler. The exclusion of HA oils from car tires has started, and an environmental labeling of tires could make HA oils obsolete. The toxicity to Daphnia magna from 12 randomly selected car tires was tested in this study. Rubber from the tread of the tires was grated into small pieces, to simulate material from tire wear, and the rubber was equilibrated with dilution water for 72 h before addition of test organisms. The 24-h EC50s of the rubber pieces ranged from 0.29 to 32 gl-1, and the 48-h EC50s ranged from 0.0625 to 2.41 gl-1. Summer tires were more toxic than winter tires. After the 48-h exposure, the daphnids were exposed to UV-light for 2 h, to determine if the tires contained compounds that were phototoxic. After UV-activation the EC50s ranged from 0.0625 to 0.38 gl-1. Four of the 12 tires had a very distinct photoactivation, with a toxicity increase of >10 times. This study has shown that the used method for toxicity testing with Daphnia magna according to ISO 6341 could be used as a basis for environmental labeling of car tires.

Effects of functionalized fullerenes on bifenthrin and tribufos toxicity to Daphnia magna: Survival, reproduction, and growth rate.

Science.gov (United States)

Brausch, Kathryn A; Anderson, Todd A; Smith, Philip N; Maul, Jonathan D

2010-11-01

Incorporation of carbon nanomaterials into industrial and consumer products is increasing, yet their impact on aquatic ecosystems alone and in chemical mixtures is largely unknown. Carbon nanomaterials may be found in the aquatic environment as mixtures with pesticides because of their proposed use in agriculture as smart delivery systems and nanosensors. The interaction effects of a functionalized fullerene ([1,2-methanofullerene C₆₀]-61-carboxylic acid) (fC₆₀) at 52.8 µg/L and the hydrophobic pesticides bifenthrin and tribufos were examined. The test organism was Daphnia magna, and response variables included 48-h survival, reproduction (bifenthrin, 70-d; tribufos, 21-d), and 10-d growth. Both pesticides reduced D. magna survival and reproduction (p bifenthrin acute toxicity but did not significantly affect chronic endpoints or growth (p > 0.05). Median lethal concentrations (LC50s), median inhibition concentrations (IC50s) for days surviving, and IC50s for reproduction were 0.86, 0.55, and 0.49 µg/L for bifenthrin; 0.22, 0.39, and 0.77 µg/L for fC₆₀-bifenthrin mix; 6.63, 9.89, and 5.79 µg/L for tribufos; and 9.17, 8.17, and 6.59 µg/L for fC₆₀-tribufos mix. Mixtures did not affect instantaneous growth rate (p > 0.05). These results suggest that fC₆₀ had little effect on pesticide chronic toxicity but influenced acute toxicity. Given the widespread application of nanotechnology, the influence of nanomaterials on environmental contaminants is an important consideration. Thus, our results may be useful in the development and use of nanotechnology in agricultural practices. © 2010 SETAC.

Effect of graded hyperventilation on cerebral metabolism in a cisterna magna blood injection model of subarachnoid hemorrhage in rats

DEFF Research Database (Denmark)

Ma, Xiaodong; Bay-Hansen, Rikke; Hauerberg, John

2006-01-01

In subarachnoid hemorrhage (SAH) with cerebrovascular instability, hyperventilation may induce a risk of inducing or aggravating cerebral ischemia. We measured cerebral blood flow (CBF) and cerebral metabolic rates of oxygen (CMRO2), glucose (CMRglc), and lactate (CMRlac) at different PaCO2 level...

Can interpreting sediment toxicity tests a mega sites benefit from novel approaches to normalization to address batching of tests?

Science.gov (United States)

Sediment toxicity tests are a key tool used in Ecological Risk Assessments for contaminated sediment sites. Interpreting test results and defining toxicity is often a challenge. This is particularly true at mega sites where the testing regime is large, and by necessity performed ...

Sustainability of mega water diversion projects: Experience and lessons from China.

Science.gov (United States)

Yu, Min; Wang, Chaoran; Liu, Yi; Olsson, Gustaf; Wang, Chunyan

2018-04-01

Water availability and water demand are not evenly distributed in time and space. Many mega water diversion projects have been launched to alleviate water shortages in China. This paper analyzes the temporal and spatial features of 59 mega water diversion projects in China using statistical analysis. The relationship between nine major basins is measured using a network analysis method, and the associated economic, environmental and social impacts are explored using an impact analysis method. The study finds the development of water diversion has experienced four stages in China, from a starting period through to a period of high-speed development. Both the length of water diversion channels and the amount of transferred water have increased significantly in the past 50years. As of 2015, over 100billionm 3 of water was transferred in China through 16,000km in channels. These projects reached over half of China's provinces. The Yangtze River Basin is now the largest source of transferred water. Through inter-basin water diversion, China gains the opportunity to increase Gross Domestic Product by 4%. However, the construction costs exceed 150 billion US dollars, larger than in any other country. The average cost per unit of transferred water has increased with time and scale but decreased from western to eastern China. Furthermore, annual total energy consumption for pumping exceeded 50billionkilowatt-hours and the related greenhouse gas emissions are estimated to be 48milliontons. It is worth noting that ecological problems caused by water diversion affect the Han River and Yellow River Basins. Over 500 thousand people have been relocated away from their homes due to water diversion. To improve the sustainability of water diversion, four kinds of innovative measures have been provided for decision makers: national diversion guidelines, integrated water basin management, economic incentives and ex-post evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.

Regional disparity and cost-effective SO2 pollution control in China: A case study in 5 mega-cities

International Nuclear Information System (INIS)

Kanada, Momoe; Dong, Liang; Fujita, Tsuyoshi; Fujii, Minoru; Inoue, Tsuyoshi; Hirano, Yujiro; Togawa, Takuya; Geng, Yong

2013-01-01

With rapid development, increasing sulfur dioxide (SO 2 ) emission becomes a key environmental issue in China. To respond to this challenge, the Chinese government established a top-down scheme to reduce its SO 2 emissions. However, regional disparity and the associated cost differences brought uncertainties to the policy effectiveness and efficiency. Few studies focus on this field. Therefore, this study tries to fill such a gap by investigating the differences of SO 2 emissions, reduction potential, and cost-effectiveness through use of the GAINS-China model in five mega-cities in China, namely, Beijing, Shanghai, Tianjin, Chongqing, and Hong Kong. A scenario analysis approach is employed, focusing on two technologies named flue gas desulfurization (FGD) and limestone injection (LINJ). Results demonstrated that a large SO 2 reduction potential exists, as well as a great disparity, among the five mega-cities. Chongqing had the largest reduction potential with lowest unit cost, while Beijng and Hong Kong showed the lowest reduction potential with higher unit cost. In Beijing and Shanghai, FGD and LINJ in the power generation sector had the larger reduction potential with the highest cost-effectiveness. However, in Chongqing, the industry sectors also had large reduction potentials. Finally, appropriate SO 2 control strategies and policies are raised by considering the local realities. - Highlights: • The cost-effectiveness of SO 2 control policy was analyzed in five mega-cities in China. • Reduction potential and cost-effectiveness were closely linked to regional disparity. • Beijing and Hong Kong showed lower reduction potential and higher marginal reduction cost. • Chongqing showed the largest reduction potential and the lowest marginal reduction cost

TERRITORIOS SOLIDARIOS DE AMÉRICA LATINA Y TURISMO COMUNITARIO EN REBOTE A LOS MEGA EMPREEMDIMENTOS TRANSNACIONAL

Directory of Open Access Journals (Sweden)

Luzia Neide Coriolano

2013-07-01

Full Text Available Este estudio analiza territorios solidarios de turismo comunitario en países de América Latina como un contrapunto al turismo convencional, de los mega emprendimientos transnacionales. Cambios en el modelo socioeconómico con movimientos de resistencia a la supuesta hegemonía de los países ricos, superposiciones de  megaempresas a la de pequeña escala, en relación al turismo global, convencional, dedicado a los mega emprendimientos vinculados con la especulación inmobiliaria. Verifica como países fortalecen territorios de economías solidarias, comunitarias. Como se crean sinergias, socialización de conocimientos en territorios como una forma de reducir las disparidades espaciales y las desigualdades sociales. Identifica experiencias con referencia de políticas de inclusión social, que promueven pequeñas ciudades, barrios, suburbios y comunidades, mitigan distancias entre ricos y pobres. Articulaciones entre aspectos políticos e institucionales para gestiones participativas y estrategias como cuestiones ambientales y de sostenibilidad socio-económica y desarrollo de comunidades que buscan soluciones económicas y sociales por el turismo, en América Latina.

HUBUNGAN ANTARA PSYCHOLOGICAL CAPITAL DENGAN WORK ENGAGEMENT PADA KARYAWAN PT. BANK MEGA REGIONAL AREA SEMARANG

Directory of Open Access Journals (Sweden)

Dwi Ari Setyo Nugroho

2015-07-01

Full Text Available This study aimed to assess the relationship between psychological capital with work engagement employees of PT. Bank Mega Regional Area Semarang. Psychological capital is an individual’s positive psychological state of development and is characterized by self- efficacy, optimism, hope and resiliency. Then, work engagement is defined as a positive, fulfilling, work-related state of mind that is characterized by vigor, dedication, and absorption. This study used proportional sampling technique. The subjects were all employees of PT. Bank Mega Regional Area Semarang which have staff levels (N=73. The research instrument was psychological capital scales with 28 items (α = 0.953 and work engagement scales with 29 items (α = 0.938. The results by simple regression analysis obtained rxy = 0.716, with p value = 0.000 (p <0.05. The results indicated that there was a positive correlation between psychological capital and work engagement. The higher psychological capital was higher work engagement. Coefficient of determination by 51,3, it meaning that psychological capital effectively contributed for 51,3 % of work engagement. The remaining 48,7 % determined by other factors that are not revealed in this study, for example: job resources and job demands. Keywords: Psychological capital, work engagement, employee

First physics results from the MAST Mega-Amp Spherical Tokamak

International Nuclear Information System (INIS)

Sykes, A.; Ahn, J.-W.; Akers, R.; Arends, E.; Carolan, P.G.; Counsell, G.F.; Fielding, S. J.; Gryaznevich, M.; Martin, R.; Price, M.; Roach, C.; Shevchenko, V.; Tournianski, M.; Valovic, M.; Walsh, M.J.; Wilson, H.R.

2001-01-01

First physics results are presented from MAST (Mega-Amp Spherical Tokamak), one of the new generation of purpose built spherical tokamaks (STs) now commencing operation. Some of these results demonstrate, for the first time, the novel effects of low aspect ratio, for example, the enhancement of resistivity due to neo-classical effects. H-mode is achieved and the transition to H-mode is accompanied by a tenfold steepening of the edge density gradient which may enable the successful application of electron Bernstein wave heating in STs. Studies of halo currents show that these less than expected from conventional tokamak results, and measurements of divertor power loading confirm that most of the power flows to the outer strike points, easing the power handling on the inner points (a critical issue for STs)

Sequence analysis of ribosomal and mitochondrial genes of the giant liver fluke Fascioloides magna (Trematoda: Fasciolidae): intraspecific variation and differentiation from Fasciola hepatica

Czech Academy of Sciences Publication Activity Database

Kráľová-Hromadová, I.; Špakulová, M.; Horáčková, Eva; Turčeková, Ĺ.; Novobilský, A.; Beck, R.; Koudela, Břetislav; Marinculić, A.; Rajský, D.; Pybus, M.

2008-01-01

Roč. 94, č. 1 (2008), s. 58-67 ISSN 0022-3395 R&D Projects: GA ČR GD524/03/H133; GA AV ČR IAA6022404 Grant - others:Slovak Research and Development Agency(SK) APVV-51-062205 Institutional research plan: CEZ:AV0Z60220518 Keywords : Fascioloides magna * Fasciola hepatica * ribosomal genes * mitochondrial genes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.165, year: 2008

Promoting effects on reproduction increase population vulnerability of Daphnia magna.

Science.gov (United States)

Agatz, Annika; Hammers-Wirtz, Monika; Gabsi, Faten; Ratte, Hans Toni; Brown, Colin D; Preuss, Thomas G

2012-07-01

Environmental risk assessment of chemicals is based on single species tests at the individual level with single compounds. However, the protection goal is the sustainability of a population, which faces several natural stressors and mixtures of chemicals in the environment. Therefore, experiments were undertaken to quantify the combined effects of chemicals with different modes of action on Daphnia magna populations. Populations continuously exposed to dispersogen A and at abundance equilibrium were treated with a 2-d pulse of p353-nonylphenol. In previous studies, dispersogen A was shown to act as a natural info-chemical, promoting the reproduction of daphnids (higher offspring quantity) coupled with reduced offspring fitness, whereas nonylphenol in pulsed-exposure caused size-selective mortality. Dispersogen A caused accelerated population growth to maximum abundance, shifted the population structure towards smaller individuals, and increased the population sensitivity to nonylphenol. The authors showed that a positive effect observed at the individual level can be transposed to a negative effect when monitored at the population level. So far, positive effects are not addressed in environmental risk assessment, and even in higher-tier testing, population structure is not quantified. Both factors indicate a potential mismatch between protection aim and risk assessment practice. Copyright © 2012 SETAC.

Mechanical properties of a co-extruded Metallic Glass/Alloy (MeGA) rod-Effect of the metallic glass volume fraction

International Nuclear Information System (INIS)

Gravier, S.; Blandin, J.J.; Suery, M.

2010-01-01

A Metallic Glass/Alloy (MeGA) rod with a core in zirconium-based bulk metallic glass and a sleeve in aluminium alloy has been successfully elaborated by co-extrusion. SEM observations of the cross-section of the rod show that the interface between the glass and the alloy is defect-free. Compression tests are carried out at room temperature on the MeGA rods containing various glass volume fractions. The yield stress is well described by the rule of mixtures which combines the strength of the glass and that of the alloy, suggesting isostrain behaviour as could be expected. During compression, a good mechanical bonding is observed in the MeGA-rod even after the first fracture of the metallic glass. Finally, push-out tests are performed to evaluate the bonding quality between the two materials. Large values of the shear strength are measured which confirms that co-extrusion leads to good bonding between the glass and the aluminium alloy.

L’ASPETTO URBANO DEL SOTTOSVILUPPO: LE MEGA CONURBAZIONI

Directory of Open Access Journals (Sweden)

Jesús Carlos Morett Sánchez

2016-06-01

Full Text Available As a result of globalization, in developing countries, the imbalance between the regions has increased, since the population is, more and more, addressed towards large settlements, inhabited by millions of people, in very precarious conditions, together with the lack of the most essential municipal services; therefore, these places are cities just for their size. They are concentrations of human beings, the result of the backwardness of their countries, making it even more difficult to develop. Are Mega Aglomeraciones Humanas Urbanas (MAHU, the impact of the unequal regional development in poor countries (whose economy is concentrated in some areas, and the ruin of small farms, for which it is very difficult to compete with large food companies. As a result, huge masses of people, who are unable to survive in rural areas of poor countries, migrate to the cities. It is not a process of attraction of the city, but the expulsion of people from fields, farms and forests, which - as a last option - move to urban areas that offer few opportunities for formal and well paid employment.

Behavior and chronic toxicity of two differently stabilized silver nanoparticles to Daphnia magna

DEFF Research Database (Denmark)

Sakka, Yvonne; Skjolding, Lars Michael; Mackevica, Aiga

2016-01-01

While differences in silver nanoparticle (AgNP) colloidal stability, surface potential, or acute aquatic toxicity for differently stabilized AgNP have often been reported, these have rarely been studied in long-term ecotoxicity tests. In the current study, we investigated the chronic toxicity of Ag...... types of AgNP during a typical media exchange period in the D. magna test for chronic toxicity. As expected, the sterically stabilized AgNP were more stable in the test medium, also in the presence of food; however, a higher uptake of silver after 24 h exposure of the charge stabilized AgNP was found...... compared to the detergent-stabilized AgNP (0.046 ± 0.006 μg Ag μg DW−1 and 0.023 ± 0.005 μg Ag μg DW−1, respectively). In accordance with this, the higher reproductive effects and mortality were found for the charge-stabilized than for the sterically-stabilized silver nanoparticles in 21-d tests...

Deep-sea seabed habitats: Do they support distinct mega-epifaunal communities that have different vulnerabilities to anthropogenic disturbance?

Science.gov (United States)

Bowden, David A.; Rowden, Ashley A.; Leduc, Daniel; Beaumont, Jennifer; Clark, Malcolm R.

2016-01-01

Growing economic interest in seabed resources in the deep-sea highlights the need for information about the spatial distribution and vulnerability to disturbance of benthic habitats and fauna. Categorisation of seabed habitats for management is often based on topographic features such as canyons and seamounts that can be distinguished using regional bathymetry ('mega-habitats'). This is practical but because such habitats are contiguous with others, there is potential for overlap in the communities associated with them. Because concepts of habitat and community vulnerability are based on the traits of individual taxa, the nature and extent of differences between communities have implications for strategies to manage the environmental effects of resource use. Using towed video camera transects, we surveyed mega-epifaunal communities of three topographically-defined habitats (canyon, seamount or knoll, and continental slope) and two physico-chemically defined meso-scale habitats (cold seep and hydrothermal vent) in two regions off New Zealand to assess whether each supports a distinct type of community. Cold seep and hydrothermal vent communities were strongly distinct from those in other habitats. Across the other habitats, however, distinctions between communities were often weak and were not consistent between regions. Dissimilarities among communities across all habitats were stronger and the density of filter-feeding taxa was higher in the Bay of Plenty than on the Hikurangi Margin, whereas densities of predatory and scavenging taxa were higher on the Hikurangi Margin. Substratum diversity at small spatial scales (the general utility of topographically-defined mega-habitats in environmental management, (2) fine-scale survey of individual features is necessary to identify the locations, characteristics, and extents of ecologically important or vulnerable seabed communities, and (3) evaluation of habitat vulnerability to future events should be in the context of

Discordant K-Ar ages between hornblende and biotite from the Tanzawa tonalitic pluton in the southern Fossa Magna, central Japan

International Nuclear Information System (INIS)

Sato, Kohei; Shibata, Ken; Uchiumi, Shigeru

1986-01-01

K-Ar ages were determined for hornblende and biotite in three tonalites from the Tanzawa pluton in the southern Fossa Magna, central Japan. The two minerals show discordant ages of 10.1 and 10.7 Ma for hornblende and 4.6 - 5.1 Ma for biotite. The age data and field evidence indicate that the pluton was emplaced in the Tanzawa Group in Middle Miocene time and its slow cooling (ca. 50 deg C/Ma in average) resulted in younger ages of boitites than hornblendes due to lower closure temperature for biotite. (author)

Not all that glitters is gold - Electron microscopy study on uptake of gold nanoparticles in Daphnia magna and related artefacts

DEFF Research Database (Denmark)

Jensen, Louise Helene Søgaard; Skjolding, Lars Michael; Thit, Amalie

2017-01-01

techniques are used to investigate internalization of 10 nm gold nanoparticles in Daphnia magna gut lumen and gut epithelial cells upon 24h exposure and outline potential artefacts, i.e. high contract precipitates from sample preparation related to these techniques. Light sheet microscopy confirmed...... accumulation of gold nanoparticles in the gut lumen. Scanning transmission electron microscopy and elemental analysis revealed gold nanoparticles attached to the microvilli of gut cells. Interestingly, the peritrophic membrane appeared to act as a semipermeable barrier between the lumen and the gut epithelium...

Comparing humic substance and protein compound effects on the bioaccumulation of perfluoroalkyl substances by Daphnia magna in water.

Science.gov (United States)

Xia, Xinghui; Dai, Zhineng; Rabearisoa, Andry Harinaina; Zhao, Pujun; Jiang, Xiaoman

2015-01-01

The influence of humic substances and protein compounds on the bioaccumulation of six types of perfluoroalkyl substances (PFASs) in Daphnia magna was compared. The humic substances included humic acid (HA) and fulvic acid (FA), the protein compounds included chicken egg albumin (albumin) and peptone, and the PFASs included perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid, perfluoroundecanoic acid, and perfluorododecanoic acid. Four concentrations (0, 1, 10, and 20 mg L(-1)) of the four dissolved organic matter (DOM) types were investigated. At the 1 mg L(-1) level, HA and albumin enhanced all tested PFAS bioaccumulation, whereas FA and peptone only enhanced the bioaccumulation of shorter-chain PFASs (PFOS, PFOA, and PFNA). However, all four DOM types decreased all tested PFAS bioaccumulation at the 20 mg L(-1) level, and the decreasing ratios of bioaccumulation factors caused by FA, HA, albumin, and peptone were 1-49%, 23-77%, 17-58%, and 8-56%, respectively compared with those without DOM. This is because DOM not only reduced the bioavailable concentrations and uptake rates of PFASs but also lowered the elimination rates of PFASs in D. magna, and these opposite effects would change with different DOM types and concentrations. Although the partition coefficients (L kg(-1)) of PFASs between HA and water (10(4.21)-10(4.98)) were much lower than those between albumin and water (10(4.92)-10(5.86)), their effects on PFAS bioaccumulation were comparable. This study suggests that although PFASs are a type of proteinophilic compounds, humic substances also have important effects on their bioavailability and bioaccumulation in aquatic organisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

The effect of food on the respiration rates of Daphnia magna using a flow-through system

Directory of Open Access Journals (Sweden)

Claire Schmoker

2003-09-01

Full Text Available Respiration rates and gut fluorescence of the cladoceran Daphnia magna were studied using a flow-through system. This open system has the advantage of introducing food or producing a starvation effect during the course of the experiment. Severe variations in respiratory rates were observed in relation to the presence or absence of food, indicating short-term variability. Organisms kept starved or at low food for a long period (15-20 h responded to a sudden increase in food by increasing their respiration rates three- to four-fold in parallel with their gut content. A significant relationship between gut fluorescence and respiration rates was observed, suggesting that feeding and the related swimming activity were responsible for the observed metabolic variability.

Activation induced changes in GABA: Functional MRS at 7T with MEGA-sLASER.

Science.gov (United States)

Chen, Chen; Sigurdsson, Hilmar P; Pépés, Sophia E; Auer, Dorothee P; Morris, Peter G; Morgan, Paul S; Gowland, Penny A; Jackson, Stephen R

2017-08-01

Functional magnetic resonance spectroscopy (fMRS) has been used to assess the dynamic metabolic responses of the brain to a physiological stimulus non-invasively. However, only limited information on the dynamic functional response of γ-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain, is available. We aimed to measure the activation-induced changes in GABA unambiguously using a spectral editing method, instead of the conventional direct detection techniques used in previous fMRS studies. The Mescher-Garwood-semi-localised by adiabatic selective refocusing (MEGA-sLASER) sequence was developed at 7T to obtain the time course of GABA concentration without macromolecular contamination. A significant decrease (-12±5%) in the GABA to total creatine ratio (GABA/tCr) was observed in the motor cortex during a period of 10min of hand-clenching, compared to an initial baseline level (GABA/tCr =0.11±0.02) at rest. An increase in the Glx (glutamate and glutamine) to tCr ratio was also found, which is in agreement with previous findings. In contrast, no significant changes in NAA/tCr and tCr were detected. With consistent and highly efficient editing performance for GABA detection and the advantage of visually identifying GABA resonances in the spectra, MEGA-sLASER is demonstrated to be an effective method for studying of dynamic changes in GABA at 7T. Copyright © 2017 Elsevier Inc. All rights reserved.

Modelling and evaluating municipal solid waste management strategies in a mega-city: The case of Ho Chi Minh City

NARCIS (Netherlands)

ThiKimOanh, L.; Bloemhof-Ruwaard, J.M.; Buuren, van J.C.L.; Vorst, van der J.G.A.J.; Rulkens, W.H.

2015-01-01

Ho Chi Minh City is a large city that will become a mega-city in the near future. The city struggles with a rapidly increasing flow of municipal solid waste and a foreseeable scarcity of land to continue landfilling, the main treatment of municipal solid waste up to now. Therefore, additional

Voxel-based morphometry multi-center mega-analysis of brain structure in social anxiety disorder

DEFF Research Database (Denmark)

Bas-Hoogendam, Janna Marie; van Steenbergen, Henk; Nienke Pannekoek, J.

2017-01-01

was used, focusing on the basal ganglia, the amygdala-hippocampal complex, the prefrontal cortex, and the parietal cortex. SAD-patients had larger GM volume in the dorsal striatum when compared to HC-participants. This increase correlated positively with the severity of self-reported social anxiety...... symptoms. No SAD-related differences in GM volume were present in the other ROIs. Thereby, the results of this mega-analysis suggest a role for the dorsal striatum in SAD, but previously reported SAD-related changes in GM in the amygdala, hippocampus, precuneus, prefrontal cortex and parietal regions were...

An attempt for unification of microcosmos and mega(macro)cosmos on the base of the order (causality)

Science.gov (United States)

Kartsaklis, Anastassios

1986-05-01

An axiomatic system of causal space and its topological structure is given that is convenient for many kinds of spacetime frame reference. Also presented is a topology of the pure states, according to axiomatic foundation of quantum mechanics by Jauch (1968). Finally, an attempt is made to unify, from a causality point of view, the microcosmos and mega(macro)cosmos supported by the transition probability.

On the Strength of the Carbon Nanotube-Based Space Elevator Cable: From Nano- to Mega-Mechanics

OpenAIRE

Pugno, Nicola M.

2006-01-01

In this paper different deterministic and statistical models, based on new quantized theories proposed by the author, are presented to estimate the strength of a real, thus defective, space elevator cable. The cable, of ~100 megameters in length, is composed by carbon nanotubes, ~100 nanometers long: thus, its design involves from the nano- to the mega-mechanics. The predicted strengths are extensively compared with the experiments and the atomistic simulations on carbon nanotubes available i...

Overview of the ARGOS X-ray framing camera for Laser MegaJoule

Energy Technology Data Exchange (ETDEWEB)

Trosseille, C., E-mail: clement.trosseille@cea.fr; Aubert, D.; Auger, L.; Bazzoli, S.; Brunel, P.; Burillo, M.; Chollet, C.; Jasmin, S.; Maruenda, P.; Moreau, I.; Oudot, G.; Raimbourg, J.; Soullié, G.; Stemmler, P.; Zuber, C. [CEA, DAM, DIF, F-91297 Arpajon (France); Beck, T. [CEA, DEN, CADARACHE, F-13108 St Paul lez Durance (France); Gazave, J. [CEA, DAM, CESTA, F-33116 Le Barp (France)

2014-11-15

Commissariat à l’Énergie Atomique et aux Énergies Alternatives has developed the ARGOS X-ray framing camera to perform two-dimensional, high-timing resolution imaging of an imploding target on the French high-power laser facility Laser MegaJoule. The main features of this camera are: a microchannel plate gated X-ray detector, a spring-loaded CCD camera that maintains proximity focus in any orientation, and electronics packages that provide remotely-selectable high-voltages to modify the exposure-time of the camera. These components are integrated into an “air-box” that protects them from the harsh environmental conditions. A miniaturized X-ray generator is also part of the device for in situ self-testing purposes.

Impaired reproduction and individual growth of the water flea Daphnia magna as consequence of exposure to the non-ester pyrethroid etofenprox.

Science.gov (United States)

Sancho, Encarna; Banegas, Sandra; Villarroel, María José; Ferrando, Dolores

2018-03-01

The effect of the pesticide etofenprox (0.76, 0.95, 1.18, 1.48, and 1.85 μg L -1 ) on survival, reproduction, and growth of Daphnia magna organisms was monitored using 21-day exposure tests. In order to test pesticide effects on D. magna, survival, length, mean total neonates per female, mean brood size, time to first reproduction, mean number broods per female, cumulative molting, and the population parameter intrinsic rate of natural increase (r) were used. Reproduction was seriously affected by etofenprox. Concentrations of etofenprox higher than 1.18 μg L -1 affected all the reproductive parameters analyzed as well as individual length. However, daphnids' survival after 21 days of pesticide exposure did not exhibited differences among experimental and control groups. The no observed effect concentration (NOEC), the lowest observed effect concentration (LOEC), and the maximum acceptable toxicant concentration (MATC) were calculated for the different parameters. A MATC estimation of 1.32 μg L -1 was calculated for mean brood size, mean number of broods per female, mean number of neonates per female, and the intrinsic rate of growth population. Etofenprox effect on the algae Nannochloris oculata was also evaluated. The selected etofenprox concentrations did not affect algal growth rate (μ) after 24 h; however, N. oculata exposed during 48 and 72 h to the highest etofenprox concentration showed a decreased in its population rate.

Teores de ácidos graxos em ovos comerciais convencionais e modificados com ômega-3 Fatty acids levels in conventional and designer omega-3 commercial eggs

Directory of Open Access Journals (Sweden)

Thaiz Marinho Magalhães Cedro

2010-08-01

Full Text Available Objetivou-se comparar os teores de ácidos graxos em ovos comerciais convencionais e em ovos modificados com ômega-3. Foram utilizadas 864 poedeiras da linhagem Isa Brown aleatoriamente distribuídas em dois grupos, de modo que cada gaiola com quatro aves foi considerada uma repetição, totalizando 216 repetições. No grupo para produção de ovos convencionais, as aves foram alimentadas durante toda a vida produtiva com ração à base de milho e farelo de soja, enquanto, no grupo para produção de ovos modificados, foram alimentadas, a partir da 22ª semana de idade, com ração contendo 1,5% de substrato de algas marinhas e 1,8% de óleo de peixe. Foram coletados, aleatoriamente, 180 ovos de cada grupo de poedeira (totalizando 360 ovos, que foram distribuídos em delineamento de blocos ao acaso, considerando cada ovo uma repetição. Os ovos modificados com ômega-3 apresentaram menores de índice de gema, mas não diferiram dos ovos convencionais quanto aos demais parâmetros de qualidade. As médias de ácidos graxos poliinsaturados ômega-3 e de ácidos graxos monoinsaturados foram mais altas nos ovos modificados. As relações entre ácidos graxos poliinsaturados e saturados e entre ômega-6 e ômega-3 nos ovos modificados foram próximas ao ideal estimado para alimentação humana. As médias de ácidos graxos poliinsaturados da série ômega-6 e de ácidos graxos saturados nos ovos convencionais foram significativamente maiores que dos ovos modificados com ômega-3.The objective of this work was to compare the levels of fatty acids between conventional commercial eggs and designer omega-3 eggs. It was used 864 Isa Brown line laying hens randomly distributed in two groups, so each cage with four birds was considered a replicate, totalizing 216 repetitions. In the group for production of conventional eggs, birds were fed corn- and soybean-based rations during the entire productive life while in the group for production of designer

Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

Directory of Open Access Journals (Sweden)

Maíra Benchimol

Full Text Available Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

A MegaCam Survey of Outer Halo Satellites. I. Description of the Survey

Science.gov (United States)

Muñoz, Ricardo R.; Côté, Patrick; Santana, Felipe A.; Geha, Marla; Simon, Joshua D.; Oyarzún, Grecco A.; Stetson, Peter B.; Djorgovski, S. G.

2018-06-01

We describe a deep, systematic imaging study of satellites in the outer halo of the Milky Way. Our sample consists of 58 stellar overdensities—i.e., substructures classified as either globular clusters, classical dwarf galaxies, or ultra-faint dwarf galaxies—that are located at Galactocentric distances of R GC ≥ 25 kpc (outer halo) and out to ∼400 kpc. This includes 44 objects for which we have acquired deep, wide-field, g- and r-band imaging with the MegaCam mosaic cameras on the 3.6 m Canada–France–Hawaii Telescope and the 6.5 m Magellan-Clay telescope. These data are supplemented by archival imaging, or published gr photometry, for an additional 14 objects, most of which were discovered recently in the Dark Energy Survey (DES). We describe the scientific motivation for our survey, including sample selection, observing strategy, data reduction pipeline, calibration procedures, and the depth and precision of the photometry. The typical 5σ point-source limiting magnitudes for our MegaCam imaging—which collectively covers an area of ≈52 deg2—are g lim ≃ 25.6 and r lim ≃ 25.3 AB mag. These limits are comparable to those from the coadded DES images and are roughly a half-magnitude deeper than will be reached in a single visit with the Large Synoptic Survey Telescope. Our photometric catalog thus provides the deepest and most uniform photometric database of Milky Way satellites available for the foreseeable future. In other papers in this series, we have used these data to explore the blue straggler populations in these objects, their density distributions, star formation histories, scaling relations, and possible foreground structures.

Widespread Forest Vertebrate Extinctions Induced by a Mega Hydroelectric Dam in Lowland Amazonia.

Science.gov (United States)

Benchimol, Maíra; Peres, Carlos A

2015-01-01

Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, under-construction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species) responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments.

Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

Weathersby, S. P.; Brown, G.; Chase, T. F.; Coffee, R.; Corbett, J.; Eichner, J. P.; Frisch, J. C.; Fry, A. R.; Gühr, M.; Hartmann, N.; Hast, C.; Hettel, R.; Jobe, R. K.; Jongewaard, E. N.; Lewandowski, J. R.; Li, R. K., E-mail: lrk@slac.stanford.edu; Lindenberg, A. M.; Makasyuk, I.; May, J. E.; McCormick, D. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); and others

2015-07-15

Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

High-power optical coatings for a mega-joule class ICF laser

International Nuclear Information System (INIS)

Kozlowski, M.R.; Thomas, I.M.; Campbell, J.H.; Rainer, F.

1992-11-01

As a consequence of advancements in Inertial Confinement Fusion research, LLNL is developing plans for a new 1.5 to 2 mega-joule solid-state Nd:glass laser designed to achieve fusion ignition. The new design is possible in part due to advances in optical coatings suitable for high power laser systems. High damage threshold mirrors and polarizers are comprised of electron beam deposited dielectric multilayers. Subthreshold illumination, or laser conditioning, of the multilayer coatings results in an increase in the damage thresholds by factors of 2 to 3 at 1.06μm, thus meeting the fluence requirements of the advanced architecture. For anti-reflective coatings, protective organic coatings for non-linear crystals and phase plates for beam smoothing, sol-gel films provide high damage thresholds coatings at low cost

Effect of subcellular distribution on nC₆₀ uptake and transfer efficiency from Scenedesmus obliquus to Daphnia magna.

Science.gov (United States)

Chen, Qiqing; Hu, Xialin; Yin, Daqiang; Wang, Rui

2016-06-01

The potential uptake and trophic transfer ability of nanoparticles (NPs) in aquatic organisms have not been well understood yet. There has been an increasing awareness of the subcellular fate of NPs in organisms, but how the subcellular distribution of NPs subsequently affects the trophic transfer to predator remains to be answered. In the present study, the food chain from Scenedesmus obliquus to Daphnia magna was established to simulate the trophic transfer of fullerene aqueous suspension (nC60). The nC60 contaminated algae were separated into three fractions: cell wall (CW), cell organelle (CO), and cell membrane (CM) fractions, and we investigated the nC60 uptake amounts and trophic transfer efficiency to the predator through dietary exposure to algae or algal subcellular fractions. The nC60 distribution in CW fraction of S. obliquus was the highest, following by CO and CM fractions. nC60 uptake amounts in D. magna were found to be mainly relative to the NPs' distribution in CW fraction and daphnia uptake ability from CW fraction, whereas the nC60 trophic transfer efficiency (TE) were mainly in accordance with the transfer ability of NPs from the CO fraction. CW fed group possessed the highest uptake amount, followed by CO and CM fed groups, but the presence of humic acid (HA) significantly decreased the nC60 uptake from CW fed group. The CO fed groups acquired high TE values for nC60, while CM fed groups had low TE values. Moreover, even though CW fed group had a high TE value; it decreased significantly with the presence of HA. This study contributes to the understanding of fullerene NPs' dietary exposure to aquatic organisms, suggesting that NPs in different food forms are not necessarily equally trophically available to the predator. Copyright © 2016 Elsevier Inc. All rights reserved.

World Cup Cities Project: movement by the sport legacy of sporting mega events

Directory of Open Access Journals (Sweden)

Rodrigo Pojar Paiva

2013-11-01

Full Text Available The achievement of sporting mega events is configured as an exceptional opportunity for the promotion of sports in the host cities. For this positive legacy to happen it must be previously planned, executed and monitored. This study aimed to present the national structure of the World Cup Cities Project and analyse the results obtained in six host cities of the FIFA World Cup 2014. The results showed that the social and sports legacy was not planned by public managers and there are no systems of control and evaluation of sport in any of the host cities, until the realization of the project World Cup Cities.

Generation of mega-electron-volt electron beams by an ultrafast intense laser pulse

International Nuclear Information System (INIS)

Wang Xiaofang; Saleh, Ned; Krishnan, Mohan; Wang Haiwen; Backus, Sterling; Murnane, Margaret; Kapteyn, Henry; Umstadter, Donald; Wang Quandong; Shen Baifei

2003-01-01

Mega-electron-volt (MeV) electron emission from the interaction of an ultrafast (τ∼29 fs), intense (>10 18 W/cm 2 ) laser pulse with underdense plasmas has been studied. A beam of MeV electrons with a divergence angle as small as 1 deg. is observed in the forward direction, which is correlated with relativistic filamentation of the laser pulse in plasmas. A novel net-energy-gain mechanism is proposed for electron acceleration resulting from the relativistic filamentation and beam breakup. These results suggest an approach for generating a beam of femtosecond, MeV electrons at a kilohertz repetition rate with a compact ultrafast intense laser system

Infections by Pasteuria do not protect its natural host Daphnia magna from subsequent infections.

Science.gov (United States)

Duneau, David; Ebert, Dieter; Du Pasquier, Louis

2016-04-01

The existence of immunological memory in invertebrates remains a contentious topic. Exposure of Daphnia magna crustaceans to a noninfectious dose of the bacterium Pasteuria ramosa has been reported to reduce the chance of future infection upon exposure to higher doses. Using clonal hosts and parasites, we tested whether initial exposure of the host to the parasite (priming), followed by clearing of the parasite with antibiotic, protects the host from a second exposure (challenge). Our experiments included three treatments: priming and challenge with the same or with a different parasite clone, or no priming. Two independent experiments showed that both the likelihood of infection and the degree of parasite proliferation did not differ between treatments, supporting the conclusion that there is no immunological memory in this system. We discuss the possibility that previous discordant reports could result from immune or stress responses that did not fade following initial priming. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of pH on the toxicity and bioconcentration of sulfadiazine on Daphnia magna

DEFF Research Database (Denmark)

Anskjær, Gitte Gotholdt; Rendal, Cecilie; Kusk, Kresten Ole

2013-01-01

The antimicrobial sulfonamide sulfadiazine has in the last decades been detected in environmental water bodies, both surface and ground water. Since pH in the environment may vary considerably, this study examined the toxicity of the amphoter sulfadiazine towards Daphnia magna at pH levels of 6.......0, 7.5 and 8.5, thus taking the impact of speciation into consideration, contrary to earlier eco-toxicity studies conducted at standard conditions. Toxicity tests were performed using the standard ISO 6341 test procedure modified to accommodate the three pH levels and the toxicity was expressed as EC50....... After 48h the EC50 was determined to be 27.2, 188 and 310mgL−1 at pH 6.0, 7.5 and 8.5, respectively, thus demonstrating a significant effect of pH on the toxicity of sulfadiazine. Furthermore, the bioconcentration factor (dry weight) was determined to be 50 and 36 at pH 6.0 and 8.5, respectively...

Student Engagement and Completion in Precalculus Precalculus Mega Section: Efficiently Assisting Student Engagement and Completion with Communications and Information Technology

Science.gov (United States)

Brusi, Rima; Portnoy, Arturo; Toro, Nilsa

2013-01-01

The Precalculus Mega Section project was developed with the main purpose of improving the overall performance of the student body in Precalculus, an important gatekeeper course that affects student engagement and completion, with typical drop/failure rates of over 50 percent. Strategies such as integration of technology and additional practice…

Aerosol optical properties in the mega-cities Beijing and Guangzhou: Measurements and implications for regional air pollution, aerosol sources and remote sensing

Science.gov (United States)

Garland, R. M.; Yang, H.; Schmid, O.; Rose, D.; Gunthe, S. S.

2009-04-01

Aerosol optical properties were measured in two mega-city regions in China. The first site (Backgarden) was in a rural area approximately 60 km northwest of the mega-city Guangzhou in south China and was part of the "Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta" intensive campaign in July 2006 (PRIDE-PRD2006). The second site (Yufa) was in a suburban area approximately 40 km south of Beijing and was part of "Campaigns of Air Quality Research in Beijing" (CAREBeijing-2006) in August 2006. Both sites were designed to measure the regional pollution of the mega-cities. The optical parameters determined with a nephelometer and photoacoustic spectrometer include absorption and scattering coefficients, single scattering albedos and Angstrom exponents at multiple wavelengths (450-700 nm). In both measurement campaigns, we observed pronounced diurnal cycles in absorption and scattering coefficients and single scattering albedo, which can be explained by boundary layer mixing effects and enhanced light absorbing carbon emissions from traffic activity during the nighttime and early morning, respectively (diesel soot from regulated truck traffic). In Beijing both the extensive and the intensive properties were highly dependent upon the origin of the air mass, which indicates that not only does the aerosol concentration change with air mass origin, but so do the chemical composition and sources. When the measured air masses originated in the north and passed over Beijing, the single scattering albedo was generally low (transported into the city from the south. The scattering and absorption coefficients measured in the outflow of the Guangzhou area during PRIDE-PRD2006 were ~2 times smaller than the southerly inflow into Beijing during CARBeijing-2006, which indicates that the sources of particulate pollution south of Beijing are even stronger than those in the Pearl River Delta. In both mega-city regions the Angstrom exponent exhibited a

DEGRADATION AND CONSERVATION OF MARBLE IN THE GREEK ROMAN HADRIANIC BATHS IN LEPTIS MAGNA, LIBYA

Directory of Open Access Journals (Sweden)

Nabil.A. ABD EL-TAWAB

2012-09-01

Full Text Available The Hadrianic Baths is one of the most important archaeological sites in Leptis Magna- Libya. It was built at the command of Emperor Hadrian in the early 2nd century CE; they represent some of the most lavish structures of Leptis Magna. It is unique in design and building technique. It was built of limestone, marble and brick. This paper mainly describes the deterioration of marble. The marble in the monuments can be classified into several types, based on its color, texture, chemical composition and the constituent mineral. The Hadrianic Baths is subjected to severe degradation, due to the climate, which is typically marine. This site suffered from different weathering forms, for example, disintegration of grains, pitting, chipping, frequent flaking, multiple-flaking, fissures and biodeterioration. These weathering forms were produced by many deterioration factors, such as moisture, salt weathering, biological and micro-biological factors, changes in temperature and wind erosion. The aim of this study is to characterize the building materials at the Hadrianic Baths, especially marble, and to evaluate the role of groundwater and sea weathering on the strength of the marble exposed to the coastline of the Mediterranean. Many samples were collected from limestone, marble, mortar, plaster and salts, for analysis and investigation. Several scientific techniques were used in the study of the morphology and texture. Those methods include microscopy, such as scanning electron microscopy (SEM, polarized light microscopy (PLM and stereo microscopy. A qualitative identification of organic and inorganic chemical species was performed by using techniques such as energy-dispersive spectroscopy (EDS, X-ray diffraction (XRD and microbial investigation were also done. Our results indicated that the deterioration of marble was caused by the aggressive action of environmental agents. SEM observations indicated the occurrence of microcracks and particle aggregates

Temperature-dependent effect of filamentous cyanobacteria on Daphnia magna life history traits

Directory of Open Access Journals (Sweden)

Piotr DAWIDOWICZ

2011-08-01

Full Text Available Filamentous cyanobacteria are unsuitable food for Daphnia due to their poor manageability, poor nutritional value and, in some cases, toxicity. As the strength of harmful effects of cyanobacteria on filter-feeding zooplankton is temperature dependent, the global warming scenarios for eutrophic lakes in temperate zone might include an escalated suppression of Daphnia populations caused by the presence of cyanobacterial filaments. To test this assumption, we conducted life-table experiments with four clones of Daphnia magna fed either a green alga Scenedesmus obliquus or a non-toxic strain of filamentous cyanobacteria Cylindrospermopsis raciborskii in two temperatures (20 °C and 24 °C. Key life history parameters of Daphnia, i.e., age and size at first reproduction, fecundity, and individual growth rate, were measured. Both food and temperature significantly affected Daphnia performance, however, the effect of interaction of these two factors was ambiguous and highly genotype-dependent. We conclude that the temperature increase within the studied range will not necessarily strengthen the suppression of Daphnia growth by filamentous cyanobacteria, but may affect clonal selection within population of Daphnia, thus possibly triggering microevolutionary changes within affected populations.

Proteinas do liquido cefalorraqueano: II. Valores normais das frações proteicas obtidas por eletroforese (variações ligadas a cor, sexo e idade

Directory of Open Access Journals (Sweden)

Lucia M. Singer Vermes

1983-03-01

Full Text Available Mediante dosagens de proteínas totais e eletroforese sobre acetato de celulose de 213 amostras de LCR normal, obtidas por punção da cisterna magna, foram efetuados estudos para verificação de variações ligadas à cor, sexo e idade. Os resultados obtidos permitiram concluir que: 1. não existem diferenças ligadas à cor no proteinograma do LCR; 2. em crianças, os fatores sexo e idade não influem nos valores estudados; 3. as taxas de proteínas totais e frações protéicas do LCR normal de criança diferem das de homens e de mulheres; 4. em adultos ocorrem variações ligadas ao sexo no proteinograma do LCR; 5. em adultos, proteínas totais e todas frações protéicas, quando expressas em mg/100 ml, aumentam com o avançar da idade. Foram estabelecidas, para a metodologia usada, as taxas fisiológicas do proteinograma do LCR de crianças, homens e mulheres, separadamente.

Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive Hydrocephalus

Science.gov (United States)

Jugé, Lauriane; Pong, Alice C.; Bongers, Andre; Sinkus, Ralph; Bilston, Lynne E.; Cheng, Shaokoon

2016-01-01

Understanding neural injury in hydrocephalus and how the brain changes during the course of the disease in-vivo remain unclear. This study describes brain deformation, microstructural and mechanical properties changes during obstructive hydrocephalus development in a rat model using multimodal magnetic resonance (MR) imaging. Hydrocephalus was induced in eight Sprague-Dawley rats (4 weeks old) by injecting a kaolin suspension into the cisterna magna. Six sham-injected rats were used as controls. MR imaging (9.4T, Bruker) was performed 1 day before, and at 3, 7 and 16 days post injection. T2-weighted MR images were collected to quantify brain deformation. MR elastography was used to measure brain stiffness, and diffusion tensor imaging (DTI) was conducted to observe brain tissue microstructure. Results showed that the enlargement of the ventricular system was associated with a decrease in the cortical gray matter thickness and caudate-putamen cross-sectional area (P hydrocephalus development, increased space between the white matter tracts was observed in the CC+PVWM (P hydrocephalus development. PMID:26848844

Soil heating during the complete combustion of mega-logs and broadcast burning in central Oregon USA pumice soils

Science.gov (United States)

Jane E. Smith; Ariel D. Cowan; Stephen A. Fitzgerald

2016-01-01

The environmental effect of extreme soil heating, such as occurs with the complete combustion of large downed wood during wildfires, is a post-fire management concern to forest managers. To address this knowledge gap, we stacked logs to create ‘mega-log’ burning conditions and compared the temperature, duration and penetration of the soil heat pulse in nine high...

Mega-History and the 21st century singularity puzzle

Directory of Open Access Journals (Sweden)

Akop P. Nazaretyan

2015-06-01

Full Text Available A series of calculations carried out independently by the Australian, Russian and American re- searchers have demonstrated that a crucial global polyfurcation is expected near the middle of the 21st century. This result is drawn by extrapolating into the future the logarithmic acceleration law, which involves the phase transitions in the evolution of biosphere and anthroposphere. The paper investigates the palliatives of the planetary civilization beyond the big evolutionary Singularity in the context of Mega-history and complexity theory worldviews. It gives the mathematical deduction a universal ground and besides, helps involve some recent discoveries in psychology and cultural anthropology to tracing the forecasting attractors and scenarios. The destiny of the Earth (as well as any other planetary civilization may conclusively depend on whether or not the intellectual ac- tor succeeds in developing his inner regulation to balance the potentially unlimited developments in technological power. Particularly, this includes overcoming the macro-group identities, religious and quasi-religious ideologies, which always suggest a friend-or-foe discrimination matrix.

A mega-ethnography of eleven qualitative evidence syntheses exploring the experience of living with chronic non-malignant pain.

Science.gov (United States)

Toye, Fran; Seers, Kate; Hannink, Erin; Barker, Karen

2017-08-01

Each year over five million people develop chronic non-malignant pain and can experience healthcare as an adversarial struggle. The aims of this study were: (1) to bring together qualitative evidence syntheses that explore patients' experience of living with chronic non-malignant pain and develop conceptual understanding of what it is like to live with chronic non-malignant pain for improved healthcare; (2) to undertake the first mega-ethnography of qualitative evidence syntheses using the methods of meta-ethnography. We used the seven stages of meta-ethnography refined for large studies. The innovation of mega-ethnography is to use conceptual findings from qualitative evidence syntheses as primary data. We searched 7 bibliographic databases from inception until February 2016 to identify qualitative evidence syntheses that explored patients' experience of living with chronic non-malignant pain. We identified 82 potential studies from 556 titles, screened 34 full text articles and included 11 qualitative evidence syntheses synthesising a total of 187 qualitative studies reporting more than 5000 international participants living with chronic pain. We abstracted concepts into 7 conceptual categories: (1) my life is impoverished and confined; (2) struggling against my body to be me; (3) the quest for the diagnostic 'holy grail'; (4) lost personal credibility; (5) trying to keep up appearances; (6) need to be treated with dignity; and (7) deciding to end the quest for the grail is not easy. Each conceptual category was supported by at least 7 of the 11 qualitative evidence syntheses. This is the first mega-ethnography, or synthesis of qualitative evidence syntheses using the methods of meta-ethnography. Findings help us to understand that the decision to end the quest for a diagnosis can leave patients feeling vulnerable and this may contribute to the adversarial nature of the clinical encounter. This knowledge demonstrates that treating a patient with a sense that they

Microbiota do megaesôfago e carcinogênese Megaesophagus microbiota and carcinogenesis

Directory of Open Access Journals (Sweden)

Denis Pajecki

2003-03-01

Full Text Available INTRODUÇÃO: O risco de desenvolvimento de carcinoma esofágico em portadores de megaesôfago é 33 vezes superior ao da população em geral. Possível explicação para este fenômeno poderia estar relacionada à produção de compostos N-nitrosos na luz do órgão, a partir da transformação de nitratos da dieta em nitritos, mediada por bactérias em suspensão no líquido de estase e com o contato crônico destes carcinógenos com a mucosa esofágica. OBJETIVO: Analisar a microbiota esofágica em pacientes portadores de megaesôfago de etiologia chagásica, com especial atenção para a presença de bactérias com capacidade de redução de nitratos. CASUÍSTICA: Foram estudados prospectivamente 15 pacientes portadores de megaesôfago chagásico com idades variando de 28 a 73 anos, sendo 9 do sexo feminino e 6 do sexo masculino, que foram divididos em 3 grupos iguais de 5, de acordo com o grau de dilatação do esôfago, segundo a classificação de Rezende et al. (Grau I, Grau II e Grau III. MÉTODO: A coleta do líquido de estase para estudo microbiológico era realizada através de sonda de Levine nº 14, que era passada pela boca, por dentro de uma cânula de intubação orotraqueal nº 7,5, mantendo-se sua extremidade escondida, a fim de evitar sua contaminação. RESULTADOS: Foram obtidas 93,3% de culturas positivas com grande variedade de microrganismos e predomínio de aeróbios Gram-positivos e anaeróbios. As concentrações de microrganismos foram tanto maiores, quanto maior o grau de dilatação do esôfago. Entre os microrganismos encontrados, o Staphylococcus sp, Corynebacterium sp, Peptostreptococcus sp e a Veillonella sp foram aqueles identificados como tendo a capacidade de redução de nitratos a nitritos. CONCLUSÃO: No megaesôfago chagásico há bactérias na luz do órgão com capacidade de redução de nitratos da dieta, passo importante na produção de compostos N-nitrosos.BACKGROUND: The risk of development of

Mega-phylogeny approach for comparative biology: an alternative to supertree and supermatrix approaches.

Science.gov (United States)

Smith, Stephen A; Beaulieu, Jeremy M; Donoghue, Michael J

2009-02-11

Biology has increasingly recognized the necessity to build and utilize larger phylogenies to address broad evolutionary questions. Large phylogenies have facilitated the discovery of differential rates of molecular evolution between trees and herbs. They have helped us understand the diversification patterns of mammals as well as the patterns of seed evolution. In addition to these broad evolutionary questions there is increasing awareness of the importance of large phylogenies for addressing conservation issues such as biodiversity hotspots and response to global change. Two major classes of methods have been employed to accomplish the large tree-building task: supertrees and supermatrices. Although these methods are continually being developed, they have yet to be made fully accessible to comparative biologists making extremely large trees rare. Here we describe and demonstrate a modified supermatrix method termed mega-phylogeny that uses databased sequences as well as taxonomic hierarchies to make extremely large trees with denser matrices than supermatrices. The two major challenges facing large-scale supermatrix phylogenetics are assembling large data matrices from databases and reconstructing trees from those datasets. The mega-phylogeny approach addresses the former as the latter is accomplished by employing recently developed methods that have greatly reduced the run time of large phylogeny construction. We present an algorithm that requires relatively little human intervention. The implemented algorithm is demonstrated with a dataset and phylogeny for Asterales (within Campanulidae) containing 4954 species and 12,033 sites and an rbcL matrix for green plants (Viridiplantae) with 13,533 species and 1,401 sites. By examining much larger phylogenies, patterns emerge that were otherwise unseen. The phylogeny of Viridiplantae successfully reconstructs major relationships of vascular plants that previously required many more genes. These demonstrations

Linking sub-individual and supra-individual effects in Daphnia magna exposed to sub-lethal concentration of chlorpyrifos.

Science.gov (United States)

Ferrario, Claudia; Parolini, Marco; De Felice, Beatrice; Villa, Sara; Finizio, Antonio

2018-04-01

The main objective of the present study was to investigate possible links between sub-individual and supra-individual levels (i.e. population level) biomarkers in D. magna exposed to sublethal concentrations of the insecticide chlorpyrifos (CPF). To achieve the aim, 8-day old individuals were exposed for 96 h to two environmentally relevant concentrations of CPF (50 and 250 ng/L). Sub-individual level effects were investigated by measuring the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes, as well as by measuring the acetylcholinesterase (AChE) inhibition. In addition, the effects at supra-individual level were assessed by using a video-tracking system and analyzing changes in swimming capabilities (i.e. percentage of activity time, distance moved, and velocity). Our data have shown that daphnids exposed to both CPF concentrations were in a condition of stress which was highlighted by changes in both sub- and supra-individual biomarkers. Moreover, our results highlighted that the lowest tested CPF concentration did not modulate the antioxidant and detoxifying enzymes, whereas, an inhibition of AChE and a decrease of some parameters related to swimming behaviour (distance moved and velocity) were noted. On the contrary, significant changes in all the sub-individual biomarkers were measured at the highest tested concentration. In addition, organisms recovered the movement capability (distance moved) and also activate a mechanism of avoidance (increased swimming velocity). On the other hand, a reduction in the percent of active time was measured and this was attributed to the energy spent by organisms to activate antioxidant and detoxifying enzymes and the mechanism of avoidance. Based on these results, our study suggests the existence of a link between sub- and supra-individual levels, as the activation or non-activation in the antioxidant and detoxifying enzymes activities can led to different modifications of the swimming behaviour

Validation of a biotic ligand model on site-specific copper toxicity to Daphnia magna in the Yeongsan River, Korea.

Science.gov (United States)

Park, Jinhee; Ra, Jin-Sung; Rho, Hojung; Cho, Jaeweon; Kim, Sang Don

2018-03-01

The objective of this study was to determine whether the water effect ratio (WER) or biotic ligand model (BLM) could be applied to efficiently develop water quality criteria (WQC) in Korea. Samples were collected from 12 specific sites along the Yeongsan River (YSR), Korea, including two sewage treatment plants and one estuary lake. A copper toxicity test using Daphnia magna was performed to determine the WER and to compare to the BLM prediction. The results of the WER from YSR samples also indicated significantly different copper toxicities in all sites. The model-based predictions showed that effluent and estuary waters had significantly different properties in regard to their ability to be used to investigate water characteristics and copper toxicity. It was supposed that the slight water characteristics changes, such as pH, DOC, hardness, conductivity, among others, influence copper toxicity, and these variable effects on copper toxicity interacted with the water composition. The 38% prediction was outside of the validation range by a factor of two in all sites, showing a poor predictive ability, especially in STPs and streams adjacent to the estuary, while the measured toxicity was more stable. The samples that ranged from pH 7.3-7.7 generated stable predictions, while other samples, including those with lower and the higher pH values, led to more unstable predictions. The results also showed that the toxicity of Cu in sample waters to D. magna was closely proportional to the amounts of acidity, including the carboxylic and phenolic groups, as well as the DOC concentrations. Consequently, the acceptable prediction of metal toxicity in various water samples needs the site-specific results considering the water characteristics such as pH and DOC properties particularly in STPs and estuary regions. Copyright © 2017 Elsevier Inc. All rights reserved.