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1.
Environ Monit Assess ; 195(5): 601, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37081198

RESUMO

In many cases, shallow coastal lagoons are, on the one hand, vulnerable habitats for birds and marine ecosystems and, on the other hand, threatened by discharging nutrient-laden surface waters and groundwater. In particular, the localization and quantification of submarine groundwater discharge (SGD) is of key concern in this regard. The presented study aimed at investigating SGD into a vulnerable coastal lagoon that is strongly impacted by evaporation applying a multi-tracer approach. The joint application of radionuclides (222Rn, 223Ra, 224Ra), stable water isotopes (δ18O, δ2H) and the water salinity as environmental water tracers allowed evaluating the suitability of the individual parameters in this specific type of environment. Whilst stable isotope and salinity data were difficult to construe in terms of SGD occurrence due to the intense impact of evaporation, a radon mass balance allowed localising SGD areas within the lagoon and quantifying the related SGD flux rates. In addition, a 224Ra/223Ra ratio analysis revealed information on the apparent age of the discharged groundwater, and hence on the flushing intensity of the lagoon. Besides these site-specific results, the study allowed the following general conclusions regarding the suitability of the applied tracers: (i) we verified the suitability of a radon mass balance approach for proving/disproving SGD occurrence and quantifying SGD fluxes in shallow coastal lagoons strongly impacted by evaporation; (ii) we showed that the impact of evaporation may impede the use of water stable isotope and salinity data as SGD indicators in such specific environments; (iii) we demonstrated that the tidal impact on a lagoon water body during a sampling campaign can be compensated by adapting sampling schedule and cruise track to the tidal cycle.


Assuntos
Água Subterrânea , Radônio , Ecossistema , Monitoramento Ambiental/métodos , Radioisótopos/análise , Radônio/análise , Água , Água do Mar
2.
Environ Monit Assess ; 194(10): 798, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36114873

RESUMO

Mapping radon (222Rn) distribution patterns in the coastal sea is a widely applied method for localizing and quantifying submarine groundwater discharge (SGD). While the literature reports a wide range of successful case studies, methodical problems that might occur in shallow wind-exposed coastal settings are generally neglected. This paper evaluates causes and effects that resulted in a failure of the radon approach at a distinct shallow wind-exposed location in the Baltic Sea. Based on a simple radon mass balance model, we discuss the effect of both wind speed and wind direction as causal for this failure. We show that at coastal settings, which are dominated by gentle submarine slopes and shallow waters, both parameters have severe impact on coastal radon distribution patterns, thus impeding their use for SGD investigation. In such cases, the radon approach needs necessarily to allow for the impact of wind speed and wind direction not only during but also prior to the field campaign.


Assuntos
Água Subterrânea , Radônio , Monitoramento Ambiental/métodos , Radônio/análise , Água do Mar , Vento
3.
4.
Nat Commun ; 11(1): 556, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992707

RESUMO

Rivers are a major supplier of particulate and dissolved material to the ocean, but their role as sources of bio-essential dissolved iron (dFe) is thought to be limited due to rapid, efficient Fe removal during estuarine mixing. Here, we use trace element and radium isotope data to show that the influence of the Congo River margin on surface Fe concentrations is evident over 1000 km from the Congo outflow. Due to an unusual combination of high Fe input into the Congo-shelf-zone and rapid lateral transport, the Congo plume constitutes an exceptionally large offshore dFe flux of 6.8 ± 2.3 × 108 mol year-1. This corresponds to 40 ± 15% of atmospheric dFe input into the South Atlantic Ocean and makes a higher contribution to offshore Fe availability than any other river globally. The Congo River therefore contributes significantly to relieving Fe limitation of phytoplankton growth across much of the South Atlantic.


Assuntos
Compostos de Ferro/análise , Ferro/análise , Rios/química , Água do Mar/química , Oceano Atlântico , Congo , Monitoramento Ambiental , Sedimentos Geológicos/química , Oceanos e Mares , Fitoplâncton/metabolismo , Radioisótopos/análise , Rádio (Elemento)/análise , Oligoelementos , Poluentes Químicos da Água/análise
5.
J Environ Radioact ; 204: 66-75, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30986717

RESUMO

To analyze plutonium (Pu) in open ocean waters can be challenging due to the low seawater concentrations. In this study we compared two techniques for Pu determination, one in-situ MnO2 cartridge system and the more commonly used MnO2 precipitation technique. During the pre-pilot GEOTRACES cruise ANT XXX-1 (2005) we tested MnO2 cartridges for the pre-concentration of Pu from seawater at 19 sampling stations on a transect in the southeastern Atlantic Ocean between Vigo (Spain) and Cape Town (South Africa). Our in-situ sampling setup consisted of one particle cartridge followed by three MnO2 cartridges in a series. Through the system we pumped between 956 and 2700 l of surface seawater with a flow rate between 1.6 and 5.2 l/min. We found that the adsorption efficiency of a single MnO2 cartridge to adsorb Pu was rather constant and on average a 58 ±â€¯7%. The adsorption efficiency was also found to be independent of seawater: temperature in the range of 18.3-29.2 °C, salinity range 34.2-37.1‰, and conductivity in the range of 46.8-58.4 mS/cm. In parallel with the in-situ sampling, discrete surface water samples between 259 and 281 l were taken and Pu was pre-concentrated using the MnO2 precipitation method. We find a good agreement between the Pu concentrations determined with the two different techniques. The in-situ pre-concentration technique requires more radiochemical work in the laboratory but has the advantage that large seawater volumes can be sampled without the necessity for radiochemical processing on-board the ship. The much larger volumes sampled with the in-situ technique compared with the precipitation technique, enables accurate determination of Pu-isotopic ratios with a low relative standard deviation. We have shown in this study that in-situ MnO2 cartridge technique can be used in a reliable way for the determination of dissolved Pu seawater concentration in open ocean waters.


Assuntos
Compostos de Manganês/química , Óxidos/química , Plutônio/análise , Monitoramento de Radiação/métodos , Água do Mar/análise , Poluentes Radioativos da Água/análise , Oceano Atlântico , Precipitação Química
6.
J Environ Radioact ; 189: 197-201, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29689484

RESUMO

The analysis of natural radium-in-water activity concentrations is for two reasons of general interest: (1) radium in natural waters may pose a problem with regard to radiation protection and (2) radium isotopes in natural waters can be used as environmental tracers in hydrological studies. A state-of-the-art method for radium extraction from (generally large) water sample volumes is radium adsorption onto MnO2 coated acrylic fibers. In our study we comparatively evaluated four methodical approaches for post-extraction preparation of the fiber to allow gamma spectrometric measurements. The methods included (1) straightforward measurement of the loose fiber, (2) compressing the fiber after mixing it with an adhesive, (3) combustion of the fiber and embedding the ash in candlewax, and (4) leaching of the fiber and embedding the resulting precipitate in candlewax. The aim of the study was to compare the advantages and disadvantages of the four preparation approaches with respect to their individual practicability. Even though the methodical fiber preparation approaches have been suggested in the literature before (as cited in this paper), results of their direct practical comparison have not been presented yet. Our study revealed that balancing practical sample preparation effort against data reproducibility suggests a measurement of the compressed fiber applying an adhesive to be the preferable approach.


Assuntos
Compostos de Manganês/química , Óxidos/química , Rádio (Elemento)/análise , Espectrometria gama/métodos , Poluentes Radioativos da Água/análise , Reprodutibilidade dos Testes
7.
J Environ Radioact ; 145: 10-18, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25863321

RESUMO

Although many researchers agree on the importance of submarine groundwater discharge (SGD), it remains difficult to locate and quantify this process. A groundwater typology was developed based on local digital elevation models and compared to concurrent radon mapping indicative of SGD in the Niantic River, CT USA. Areas of high radon activity were located near areas of high flow accumulation lending evidence to the utility of this approach to locate SGD. The benefits of this approach are three-fold: fresh terrestrial SGD may be quickly located through widely-available digital elevation models at little or no cost to the investigator; fresh SGD may also be quantified through the GIS approach by multiplying pixelated flow accumulation with the expected annual recharge; and, as these data necessarily quantify only fresh SGD, a comparison of these data with SGD as calculated by Rn activity may allow for the separation of the fresh and circulated fractions of SGD. This exercise was completed for the Niantic River where SGD as calculated by the GIS model is 1.2 m(3)/s, SGD as calculated by Rn activity is 0.73-5.5 m(3)/s, and SGD as calculated via a theoretical approach is 1.8-4.3 m(3)/s. Therefore fresh, terrestrial SGD accounts for 22-100% of total SGD in the Niantic River.


Assuntos
Sistemas de Informação Geográfica , Água Subterrânea/análise , Monitoramento de Radiação/métodos , Radônio/análise , Rios/química , Connecticut , Monitoramento Ambiental
8.
São Paulo; Editora Organon; 2014. 920 p.
Monografia em Português | HomeoIndex - Homeopatia | ID: hom-11111

RESUMO

Depois de muitos anos de intensa pesquisa, o livro PLANTAS MARAVILHOSAS de Jan Scholten, editado este com muito sucesso em vários idiomas, em breve estará disponível também em Português. Nesta obra, ele nos apresenta um sistema inovador de pesquisa de substâncias do reino vegetal. Onde as mesmas leis naturais que podem ser vistas nas séries e estágios da tabela periódica, também são a base do sistema taxonômico de famílias de plantas. Um dos valores intemporais deste trabalho reside no encontro da essência das famílias das plantas e sua aplicação prática. Jan Scholten é pioneiro na pesquisa de remédios e métodos novos em homeopatia. Autor de outras obras já traduzidas para o português pela Editora Organon, como Homeopatia e Minerais, que foi muito bem recebido pela comunidade homeopática, Lantanídeos Secretos, Homeopatia e os Elementos e a Tabela Periódica dos Elementos.


Assuntos
Materia Medica , Plantas Medicinais , Homeopatia
9.
São Paulo; Organon; 2012. 622 p.
Monografia em Português | HomeoIndex - Homeopatia | ID: hom-10784

RESUMO

A obra descreve o uso dos Lantanídeos e os seus sais na saúde e na doença. Descreve as pessoas no estado Lantanídeo e a sua cura com dinamizações homeopáticas. Os Lantanídeos são elementos da tabela periódica com número atômico entre 52 e 73, tendo fortes propriedades luminosas e eletromagnéticas.A prescrição dos lantanídeos é feita basicamente para pessoas que tem tendência a serem donas de si mesmas e a seguir o seu próprio caminho - o caminho da individualidade e da individuação. Este lado psicológico se reflete fisicamente no sistema imune e nas doenças autoimunes, onde tem uma de suas principais aplicações terapêuticas.


Assuntos
Elementos da Série dos Lantanídeos , Fundamentos da Homeopatia , Materia Medica
10.
São Paulo; Organon; 2011. 334 p.
Monografia em Português | LILACS | ID: lil-654554

RESUMO

A classificação dos medicamentos segundo os três reinos da natureza, focando basicamente as substâncias do reino mineral. Através do estudo dos medicamentos de mesma origem, das intoxicações e dos resultados práticos obtidos com seus pacientes, ele desenvolveu um método de analise das substancias em grupos e famílias. A aplicação deste processo resultou em tal sucesso que ele o transferiu para o estudo da tabela periódica e descobriu padrões relacionados às linhas e colunas dessa tabela. Desta forma, a analise dos casos mostrou-se muito mais direta, resultando numa melhor precisão e porcentagem alta de curas.


Assuntos
Homeopatia , Materia Medica , Minerais
11.
São Paulo; Organon; 2011. 334 p.
Monografia em Português | HomeoIndex - Homeopatia | ID: hom-10546

RESUMO

A classificação dos medicamentos segundo os três reinos da natureza, focando basicamente as substâncias do reino mineral. Através do estudo dos medicamentos de mesma origem, das intoxicações e dos resultados práticos obtidos com seus pacientes, ele desenvolveu um método de analise das substancias em grupos e famílias. A aplicação deste processo resultou em tal sucesso que ele o transferiu para o estudo da tabela periódica e descobriu padrões relacionados às linhas e colunas dessa tabela. Desta forma, a analise dos casos mostrou-se muito mais direta, resultando numa melhor precisão e porcentagem alta de curas.(AU)


Assuntos
Homeopatia , Materia Medica , Minerais
12.
São Paulo; Organon; 2011. 902 p.
Monografia em Português | HomeoIndex - Homeopatia | ID: hom-10782

RESUMO

O autor desenvolve os conceitos e analisa os sintomas da maioria dos elementos da tabela periódica. Ele demonstra que cada fileira, a qual ele chama de série, possue um tema especifico e as dezoito colunas correspondem a diferentes estágios do desenvolvimento.Foi exatamente isso que fez Jan scholten e o resultado é este livro: uma matéria medica homeopática do sistema periódico enriquecida de muitos novos medicamentos e informações acessíveis aos homeopatas de língua portuguesa. Este livro está inteiramente dedicado ao sistema periódico. A melhor introdução para as ideias novas apresentadas neste livro é sugerir o seguinte exercício. Pegue uma folha de papel e desenhe uma grade de dezoito colunas verticais e sete linhas horizontais e, a seguir, proceda preenchendo-a com os elementos da maneira usual, começando pelo Hidrogênio, Hélio, Lítio, etc. Em seguida, pegue a matéria médica mais extensa que encontrar e anote as rubricas mais importantes de cada elemento na casa correspondente. Quando houver terminado, dê um passo atrás e olhe. Você perceberá que a maioria dos espaços está vazia. Então, pergunte a você mesmo: “Por que há tantos espaços vazios enquanto outros estão preenchidos com policrestos como Ferrum metallicum, Phosphorus, Sulphur ou Aurum metallicum?” Você está começando a entender qual é o problema? Você acabou de fazer a você mesmo uma pergunta heurística. O único passo intermediário entre uma pergunta e uma resposta é uma ação!


Assuntos
Homeopatia , Fundamentos da Homeopatia , Medicamento Homeopático , Oligoelementos , Minerais
13.
Utrecht; Scholten; 2008. 296 p.
Monografia em Inglês | HomeoIndex - Homeopatia | ID: hom-11153
14.
Immunology ; 115(4): 495-505, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16011518

RESUMO

The capacity of farm animals to produce cytokines could be an important determinant of robustness and health. From research in rodents and humans it appears that the production and the balance of T helper 1 (Th1) and T helper 2 (Th2)-type cytokines influences susceptibility to autoimmune and infectious diseases. It is known that pigs show a large variation in many immune response parameters. So far the extent of individual variation in the production of Th1- and Th2-type cytokines in commercial outbred pigs has not been reported. In the current experiment we determined mRNA expression, as well as protein production of cytokines in 32 pigs from eight litters. From each litter two male and two female pigs were tested at 2, 5 and 8 weeks of age. Two Th1-type cytokines, interleukin (IL)-2 and interferon (IFN)-gamma, and two Th2-type cytokines, IL-4 and IL-10, were measured after phytohaemagglutinin (PHA)-stimulation of blood mononuclear cells. Cytokine production and the Th1/Th2-ratio were highly variable. The variation in cytokine protein production was moderately consistent across ages, i.e. pigs that produced high levels of cytokine at 2 weeks of age tended to do so as well at 5 and 8 weeks of age. Cytokine production tended to increase with age, and gilts and boars differed in their IL-2/IL-4 ratio. Unexpectedly, age, gender and litter effects often differed for mRNA and protein production data. We hypothesize that cytokine production is a consistent trait in pigs, especially at the protein production level. Future investigations in more animals and across a wider age range are necessary.


Assuntos
Citocinas/imunologia , Suínos/imunologia , Linfócitos T/imunologia , Fatores Etários , Animais , Feminino , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-2/imunologia , Interleucina-4/imunologia , Tamanho da Ninhada de Vivíparos/imunologia , Masculino , Biossíntese de Proteínas/imunologia , RNA Mensageiro/análise , Fatores Sexuais
15.
Physiol Behav ; 75(3): 277-85, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11897253

RESUMO

An important property of the antiviral immune response is its time-dependent character. Beginning with a few antigen-specific cells upon infection, it evolves to a stage where there is an abundance of antigen-specific cells and antibodies that are needed to clear the pathogen, and ends with circulating antibodies and a population of virus-specific memory cells to protect the animal from reinfection. Short-term effects of stress on the immune system have been investigated extensively, showing that stress acutely changes many aspects of immunity. However, relatively little is known about the consequences of stress for the quality and quantity of long-term immunological memory. In the present study, we have investigated the effect of social stress, applied in mice at Days 1, 2 and 3 after inoculation with a herpes virus, on long-term antibody and memory cytokine responses to the virus. Male mice were subjected to three 5-min confrontations with an aggressive conspecific. Approximately half of the mice was wounded by bites of the aggressor during this stress procedure, and these mice were analyzed separately from nonwounded mice. It appeared that wounded mice showed suppressed protective antibody responses and impaired memory for virus-specific IL-4 and IL-10 production, whereas mice that were not wounded showed intact long-term immune responses and memory. It is concluded that the combination of wounds and the social stress of repeated confrontations is associated with impaired protective immunity as a consequence of suppressed antibody levels and impairment of some aspects of antiviral immunological memory.


Assuntos
Mordeduras e Picadas/imunologia , Mordeduras e Picadas/psicologia , Meio Social , Estresse Psicológico/imunologia , Estresse Psicológico/psicologia , Viroses/imunologia , Viroses/psicologia , Agressão/fisiologia , Animais , Anticorpos Antivirais/biossíntese , Comportamento Animal/fisiologia , Herpesvirus Suídeo 1/imunologia , Memória Imunológica/fisiologia , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-2/biossíntese , Interleucina-4/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Baço/metabolismo
17.
Utrecht; Scholten; 1998. 296 p.
Monografia em Espanhol | HomeoIndex - Homeopatia | ID: hom-10083
18.
Simillimum ; 9(3): 55-56, 1996.
Artigo em Inglês | HomeoIndex - Homeopatia | ID: hom-7778
19.
Utrecht; Scholten; 3 ed; 1996. 296 p.
Monografia em Inglês | HomeoIndex - Homeopatia | ID: hom-10081
20.
Utrecht; Scholten; 1996. 288 p.
Monografia em Inglês | HomeoIndex - Homeopatia | ID: hom-10084
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