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Zdravstveno stanje i kvalitet mesa svinja rase mangulica i meleza između rase mangulica i duroka / The state of health of the pig meat breeds of mangulets and molasses between the race of mangulets and durokŠević Radoslav 07 February 2018 (has links)
<p>Istraživanje je sprovedeno u cilju utvrđivanja uticaja ukrštanja mangulice sa durokom na proizvodne i zdravstvene parametre, kao i na kvalitet mesa, a sve to uporedo sa jednom modernom plemenitom rasom svinja – veliki jorkšir. U tu svrhu formirane su tri grupe – genotipa svinja, čista rasa bela mangulica (BM), melezi duroka i bele mangulice (DBM), i čista rasa veliki jorkšir (VJ), koji su smešteni u iste uslove ishrane, nege i držanja. Svinje iz grupa DBM i VJ su znatno brže prirasle do ciljane telesne mase od 150 kg u odnosu na svinje BM. Tako je melezima duroka i bele mangulice trebalo u proseku 168 dana manje, a svinjama iz grupe VJ 288 dana manje kako bi dostigli ciljanu telesnu masu u odnosu na svinje bele mangulice u čistoj rasi. Po pitanju zdravstvenog stanja i nalaza na trupovima zaklanih svinja post mortem nisu utvrđene značajne razlike. Značajne razlike su utvrđene u hematološkim i biohemijskim parametrima i to između sve tri ispitivane grupe, ali i između različitih starosnih kategorija u okviru iste ispitivane grupe, što nam ukazuje na značaj tačnijeg utvrđivanja referentnih parametara normalnih fizioloških vrednosti hematoloških i biohemijskih parametara ne samo posebno za pojedine vrste životinja, već dakako i za različite starosne kategorije u okviru iste vrste. Meso poreklom od svinja iz grupe BM imalo je najveći sadržaj intramuskularne masnoće, i tamniju i crveniju boju, dok za njima odmah slede melezi sa značajnim razlikama između sva tri ispitivana genotipa. Nadalje, meso svinja rase bela mangulica je imalo značajno veću krajnju vrednost pH, bolju sposobnost vezivanja vode, veći sadržaj kalcijuma, cinka, gvožđa, bakra i mangana, u poređenju sa druga dva genotipa. Ukrštanje bele mangulice i duroka je imalo značajan uticaj na pojedinačni sastav masnih kiselina u mesu. Međutim, zbir zasićenih, mononezasićenih i polinezasićenih masnih kiselina je ostao nepromenjen. Meso svinja rase bela mangulica i meleza dobijenih ukrštanjem svinja rasa bela mangulica i durok značajno je nežnije – mekše. Mononezasićene masne kiseline su najzastupljenije u mesu poreklom od svih životinja, dok za njima slede zasićene i na kraju polinezasićene masne kiseline. Meso poreklom od BM i DBM je imalo značajno veći sadržaj mononezasićenih masnih kiselina, i značajno manji sadržaj zasićenih masnih kiselina u odnosu na VJ. Generalno, na osnovu svih ispitanih parametara kvaliteta polutki i mesa može se konstatovati da svinje rase bela mangulica karakteriše manja mesnatost polutki, ali i meso koje ima odličan senzorski, tehnološki i nutritivni kvalitet, dok meleze svinja dobijenih ukrštanjem svinja rasa bela mangulica i durok karakteriše veća mesnatost polutki i nešto slabiji, ali još uvek veoma dobar, kvalitet mesa, te su neophodna dodatna istraživanja kako bi smo dobili i podatake o kvalitetu suvomesnatih proizvoda. Takođe, potrebna su dodatna<br />istraživanja, preciznijeg karaktera u pogledu kvaliteta i ekonomičnosti proizvodnje kod autohtonih rasa, kao i preispitivanje kriterijuma selekcije koji se primenjuju kod mangulice, te parametara genetskog progresa, tj. efekta selekcije, kako bi iako autohtona uhvatila korak za opstanak ili prestiž u odnosu na moderne rase svinja.</p> / <p>The research was carried out in order to determine the effect of the cross-breeding of mangulets with durok on production and health parameters, as well as on the quality of meat, all along with a modern, noble breed of pigs - a large Yorkshire. For this purpose, three groups - pig genotypes, pure breeds of white mangulica (BM), meliaceae and white manguns (DBM), and pure breed, Yorkshire (VJ), were placed in the same conditions of nutrition, care and keeping. Pigs from the DBM and VJ groups increased significantly to a target bodyweight of 150 kg compared to BM pigs. Thus, mulberry and white mangulets were average 168 days less, and 288 days lower for pigs from the VJ group in order to reach their target body mass compared to white mangun pigs in a clean race. There are no significant differences in terms of health status and findings on carcases of slaughtered pigs post-mortem. Significant differences were established in the hematological and biochemical parameters, among all three groups studied, but also between different age categories within the same investigated group, which points to the importance of more precise determination of the reference parameters of normal physiological values of hematologic and biochemical parameters not only for individual species of animals, but also for different age categories within the same species. Meat originating from pigs from the BM group had the highest content of intramuscular fat, and the darker and redder color, followed by moles with significant differences between all three investigated genotypes. Furthermore, the pig meat of the white mangulce had a significantly higher end value of pH, better water binding capacity, higher content of calcium, zinc, iron, copper and manganese, compared to the other two genotypes. The crossing of white mangulce and durok had a significant effect on the individual composition of fatty acids in the meat. However, the sum of saturated, monounsaturated and polyunsaturated fatty acids remained unchanged. Meat of pig breeds white mangulica and molasses obtained by crossing the pig race white mangulica and durok is significantly more gentler - softer. Monounsaturated fatty acids are the most common in meat originating from all animals, followed by saturated and at the end of polyunsaturated fatty acids. Meat originating from BM and DBM had a significantly higher content of monounsaturated fatty acids, and significantly lower saturated fatty acid content than VJ. In general, on the basis of all the tested parameters of the quality of the halves and flesh, it can be concluded that the pig breeds of white mangulets are characterized by lower meatiness of the hemispheres, but also meat that has excellent sensory, technological and nutritive quality, while the piglets of pigs obtained by crossing the pig rasa white mangulica and durok are characterized by larger lean meat and slightly weaker but still very good quality of meat, and further research is needed in order to obtain data on the quality of the cream products. Also, additional ones are needed<br />research, a more precise character in terms of quality and cost-effectiveness in autochthonous breeds, as well as the reconsideration of selection criteria applied to mangulas and parameters of genetic progress, i.e. the effect of the selection, in order to take an autochthonous step in survival or prestige in relation to modern pig breeds.</p>
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ESTIMATION OF TRANSMISSION LINE PARAMETERS USING LINEAR METHOD WITH SYNCHRONIZED AND UNSYNCHRONIZED DATALahmar, Mustafa 01 January 2019 (has links)
Accurate value of transmission line parameters is important for power system protection applications, especially for distance relays whose zone settings are based on positive sequence line impedance. The research is devoted to estimating transmission line positive-sequence parameters from synchronized or unsynchronized measurements of voltage and current phasors that are obtained at both terminals of the line. The positive sequence parameters including series impedance and shunt admittance can be linearly estimated. The linear least square algorithm has been derived in this dissertation for different transmission line configurations. The algorithm is able to handle both synchronized and unsynchronized measurements and deal with potential synchronization errors by explicitly modeling the synchronization angle. Sample results are reported to demonstrate the effectiveness of the proposed method.
Three types of transmission line models depending on line length (long, medium and short) are studied in this dissertation. Chapter 3 uses unsynchronized data for the long transmission line. The derived method can detect the unsynchronized angle and estimate the positive sequence of long line parameters. The proposed method is examined with negative impacts such as errors on currents and voltages data. These errors are added randomly to one set each time to test the robustness of the developed algorithm.
The medium transmission line algorithm derivation is presented in chapter 4. This chapter uses a linear least square to estimate the lumped parameters of a medium transmission line. The two different transmission line circuits are used to model the medium line. The first circuit is a single transmission line with two nodes and is used to evaluate the developed algorithm. The second circuit is a double transmission line. These two lines can have the same or different line parameters or line length. The developed algorithm shows that the proposed method achieves highly accurate results for the estimation of positive sequence line parameters.
The short transmission line is studied in chapter 5. The short transmission line uses less data than the long or medium lines because in this model the shunt capacitance is omitted. Thus, the linear estimation yields highly accurate results. Case studies are considered to test the robustness of this developed method.
The line temperature mainly affects the series resistance, and the developed algorithms in previous three chapters can accurately estimate the transmission line parameters. To simplify the real-time estimation of line resistance and temperature, the series inductance, and shunt capacitance can be treated as constant and known values. Chapter 6 provides such studies of estimating resistance by treating inductance and capacitance as known values.
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Density functional studies of EPR and NMR parameters of paramagnetic systemsTelyatnyk, Lyudmyla G. January 2006 (has links)
Experimental methods based on the magnetic resonance phenomenon belong to the most widely used experimental techniques for investigations of molecular and electronic structure. The difficulty with such experiments, usually a proper interpretation of data obtained from high-resolution spectra, opens new challenges for pure theoretical methods. One of these methods is density functional theory (DFT), that now has an advanced position among a whole variety of computational techniques. This thesis constitutes an effort in this respect, as it presents theory and discusses calculations of electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) parameters of paramagnetic molecules. It is known that the experimental determination of the magnetic resonance parameters of such molecules, especially in the case of NMR, is quite complicated and requires special techniques of spectral detection. On the other hand, paramagnetics play an important role in many areas, such as molecular magnets, active centers in biological systems, and defects in inorganic conductive materials. Therefore, they have spurred great interest among experimentalists, motivating us to facilitate the interpretation of spectral data through theoretical calculations. This thesis describes new methodologies for the determination of magnetic properties of paramagnetic molecules in the framework of DFT, which have been developed in our laboratory, and their applications in calculations of a wide range of molecular systems. The first two papers of this thesis deal with the theoretical determination of NMRparameters, such as nuclear shielding tensors and chemical shifts, in paramagnetic nitroxides that form core units in molecular magnets. The developed methodology is aimed to realize a high calculational accuracy for these systems. The effects of hydrogen bonding are also described in that context. Our theory for the evaluation of nuclear shielding tensors in paramagnetic molecules is consistent up to second order in the fine structure constant and considers orbital, fully anisotropic dipolar, and isotropic contact contributions to the shielding tensor. The next projects concern electron paramagnetic resonance. The well-known EPR parameters, such as the g-tensors and the hyperfine coupling constants are explored. Calculations of electronic g-tensors were carried out in the framework of a spin-restricted open-shell Kohn-Sham method combined with the linear response theory recently developed in our laboratory and allowing us to avoid by definition the spin-contamination problem. The inclusion of solvent effects, described by the polarizable continuum model, extends the possibility to treat molecular systems often investigated in solution. For calculations of the hyperfine coupling constants a so-called restricted-unrestricted approach to account for the spin polarization effect has been developed in the context of DFT. To examine the validity of the approximations implicit in this scheme, the neglect ii of singlet operators, a generalized RU methodology was implemented, which includes a fully unrestricted treatment with both singlet and triplet operators. The small magnitude of the changes in hyperfine coupling constants confirms the validity of the original scheme. / QC 20100923
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An investigation into the development and status of resistance of Busseola fusca (Lepidoptera: Noctuidae) to Bt maize / Marlene KrugerKruger, Marlene January 2010 (has links)
Based on surface area, South Africa is currently ranked 8th in planting genetically
modified (GM) crops in the world. The stem borer, Busseola fusca (Fuller) (Lepidoptera:
Noctuidae) is of economic importance throughout sub–Saharan Africa. Bt maize
(MON810) has been grown to control lepidopterous stem borers in South Africa since its
first release in 1998. The first report of resistance to Bt maize was made in the
Christiana area of South Africa in 2007. The objectives of this study were to evaluate
the status of resistance of populations of B. fusca to Bt maize; to evaluate farmers'
perceptions of the regulatory aspects guiding the planting of Bt maize and refugia and
how the field situation developed between 1998 and 2010; to compare the fitness of the
fertility, fecundity and longevity of Bt–resistant and susceptible B. fusca populations and
to determine if there are fitness costs associated with resistance of B. fusca to Bt maize.
Questionnaire surveys were conducted amongst 185 farmers in seven districts
throughout the maize production region. The questionnaire addressed signing of
contracts upon purchasing GM seed, refuge compliance, pest management practices,
perceived benefits and risks relating to Bt maize. In order to study fitness and fitness
costs that may be associated with resistance development, the life history parameters of
known Bt–resistant and susceptible populations were compared in the laboratory using a
diapauses–as well as second–generation populations collected in maize fields. The
following parameters were compared between different stem borers populations and
treatments: pupal mass, moth longevity, fecundity, fertility, larval mass and survival, and
sex ratio. This study confirmed resistance of B. fusca to the Cry1Ab toxin (MON810)
and that larvae collected from refugia at Vaalharts were resistant and survived on Bt
maize. Compliance to refugia requirements was low especially during the initial 5 – 7
years after release. An alarmingly high number of farmers applied insecticides as
preventative sprays on Bt maize and refugia. Except for moth longevity and LT50–
values, no other fitness costs were observed to be associated with the resistance trait in
the highly resistant B. fusca population used in this study. The LT50 may indicate some
degree of fitness cost but does not translate into observable costs in terms of fecundity,
larval mass and survival. The absence of fitness costs may promote the use of
alternative Bt–resistance management strategies, such as the introduction of a multigene strategy. The introduction of a stacked event such as MON89034 which produces
more than one protein with activity active against the resistant target pest, together with
compliance to the refuge strategy, is most likely the only solution to managing Btresistant
stem borer populations in South Africa. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
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An investigation into the development and status of resistance of Busseola fusca (Lepidoptera: Noctuidae) to Bt maize / Marlene KrugerKruger, Marlene January 2010 (has links)
Based on surface area, South Africa is currently ranked 8th in planting genetically
modified (GM) crops in the world. The stem borer, Busseola fusca (Fuller) (Lepidoptera:
Noctuidae) is of economic importance throughout sub–Saharan Africa. Bt maize
(MON810) has been grown to control lepidopterous stem borers in South Africa since its
first release in 1998. The first report of resistance to Bt maize was made in the
Christiana area of South Africa in 2007. The objectives of this study were to evaluate
the status of resistance of populations of B. fusca to Bt maize; to evaluate farmers'
perceptions of the regulatory aspects guiding the planting of Bt maize and refugia and
how the field situation developed between 1998 and 2010; to compare the fitness of the
fertility, fecundity and longevity of Bt–resistant and susceptible B. fusca populations and
to determine if there are fitness costs associated with resistance of B. fusca to Bt maize.
Questionnaire surveys were conducted amongst 185 farmers in seven districts
throughout the maize production region. The questionnaire addressed signing of
contracts upon purchasing GM seed, refuge compliance, pest management practices,
perceived benefits and risks relating to Bt maize. In order to study fitness and fitness
costs that may be associated with resistance development, the life history parameters of
known Bt–resistant and susceptible populations were compared in the laboratory using a
diapauses–as well as second–generation populations collected in maize fields. The
following parameters were compared between different stem borers populations and
treatments: pupal mass, moth longevity, fecundity, fertility, larval mass and survival, and
sex ratio. This study confirmed resistance of B. fusca to the Cry1Ab toxin (MON810)
and that larvae collected from refugia at Vaalharts were resistant and survived on Bt
maize. Compliance to refugia requirements was low especially during the initial 5 – 7
years after release. An alarmingly high number of farmers applied insecticides as
preventative sprays on Bt maize and refugia. Except for moth longevity and LT50–
values, no other fitness costs were observed to be associated with the resistance trait in
the highly resistant B. fusca population used in this study. The LT50 may indicate some
degree of fitness cost but does not translate into observable costs in terms of fecundity,
larval mass and survival. The absence of fitness costs may promote the use of
alternative Bt–resistance management strategies, such as the introduction of a multigene strategy. The introduction of a stacked event such as MON89034 which produces
more than one protein with activity active against the resistant target pest, together with
compliance to the refuge strategy, is most likely the only solution to managing Btresistant
stem borer populations in South Africa. / Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
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Hodnocení růstových a produkčních parametrů nematofágní houby Arthrobotrys oligospora / Evaluation of growth and production parameters of nematophagous fungus \kur{Arthrobotrys oligospora}ŠEDIVÁ, Monika January 2010 (has links)
This M.Sc. thesis is aimed to describe growth and production parameters of nematophagous fungus Arthrobotrys oligospora. There was determinated information about growth and sporulation of fungus on artificial and natural substrates, influence of cultivation condition on production biomass and possibility of formulation alginate pellets.
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Estimativa de parâmetros hidrogeológicos como subsídio para modelagem de aqüífero integrada a estudos geofísicos na região de Bebedouro-SP / Estimating hydrogeological parameters as subsidy for aquifer modelling integrated to geophysical studies in Bebedouro-SP region.Ivan Mamede Carlos 30 August 2010 (has links)
Realizar a modelagem de um aqüífero não é tarefa fácil. Em se tratando de um sistema aqüífero, a empreitada se torna ainda mais complexa. Neste trabalho, alguns dos parâmetros importantes para esse fim foram estimados a partir de simulações. Na região de estudo, existem poços tubulares que, em sua maioria, não foram perfurados somente na Formação Adamantina, mas também na Formação Serra Geral. Tal configuração conduziu à formulação de dois conjuntos de cenários a partir dos quais foi possível estimar valores de condutividade hidráulica para as duas formações. Com essa estimativa conseguiu-se também simular testes de bombeamento, seus respectivos cones de rebaixamento, bem como a interferência causada entre cones de rebaixamento. Com essa abordagem foi possível estimar o quanto um poço em funcionamento pode influenciar no nível estático de um vizinho. A contribuição da geofísica está no uso da eletroresistividade. Foram executadas 23 Sondagens Elétricas Verticais (SEV), das quais dezenove são SEV´s curtas (AB/2 500m) e quatro, longas (AB/2 1500), que forneceram informações sobre a espessura saturada do arenito e posição do topo do basalto, especialmente na região com poucos poços. Também foram realizados quatro Caminhamentos Elétricos (CE) no estudo de possíveis estruturas. Unindo os resultados da modelagem (simulação) e da geofísica, pôde-se relacionar os parâmetros hidrogeológicos e geoelétricos. Embora o conjunto de dados para a região não tenha sido o ideal, a metodologia se mostrou adequada e os resultados bastante razoáveis. Deste modo, foi possível a determinação de parâmetros hidrogeológicos em subsuperfície através de parâmetros geoelétricos medidos em superfície. / To perform the aquifer modelling is not an easy task. In the case of an aquifer system, the work becomes even more complex. In this work, some of important parameters for this purpose have been estimated from simulations. In the study area, there are wells that in most cases were not only drilled in Adamantina Formation but also in Serra Geral Formation. This configuration led to the formulation of two sets of scenarios from which it was possible to estimate values for hydraulic conductivity of these formations. With this estimate it could also simulate pumping tests, their cones of depression as well as the interference caused between cones of depression. With this approach it was possible to estimate how much a operating well can influence static level of a neighbour one. Geophysics contribution is in the use of electrical resistivity. Twenty-three Vertical Electrical Soundings (VES) were performed, nineteen of them are short (AB/2 500m), that provided information about the saturated thickness of sandstone as well as top of basalt, especially in the region with few wells, and four are long (AB/2 1500) VESs. Four electrical profiling (EP) were also carried out to study possible structures. Joining modelling (simulation) and geophysics results, it could be related hydrogeological and geoelectrical parameters. Although dataset for region was not the ideal, methodology was satisfactory, and results quite reasonable. Thus, it was possible to determine hydrogeological parameters in subsurface through measured geoelectrical parameters in surface.
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[en] INFLUENCE OF ECOLOGICAL AND BIOLOGICAL PARAMETERS ON THE ACCUMULATION OF ESSENTIAL (SE, AS, CU) AND NON-ESSENTIAL ELEMENTS (HG, CD, AG, PB) BY THE LIVER AND KIDNEY OF CETACEANS FROM THE WESTERN SOUTH ATLANTIC OCEAN / [pt] INFLUÊNCIA DE PARÂMETROS ECOLÓGICOS E BIOLÓGICOS NA ACUMULAÇÃO DE ELEMENTOS ESSENCIAIS (SE, AS, CU) E NÃO-ESSENCIAIS (HG, CD, AG, PB) EM FÍGADO E RINS DE CETÁCEOS DA PORÇÃO OESTE DO OCEANO ATLÂNTICO SULTERCIA GUEDES SEIXAS 23 January 2009 (has links)
[pt] Neste estudo, avaliou-se a influência de alguns
parâmetros
ecológicos e biológicos sobre a acumulação dos elementos-
traço e mercúrio orgânico (HgOrg)no fígado e rins de
espécies de cetáceos de hábitos costeiros (Pontoporia
blainvillei, N = 31; Sotalia guianensis, N = 21) e
oceânicos (Stenella coeruleoalba, N = 3; Stenella
frontalis, N = 4), acidentalmente capturados em
duas áreas distintas da costa brasileira (tropical -
litoral do norte do estado do Rio de Janeiro e
subtropical -
litoral do estado do Rio Grande do Sul). Assim, foram
gerados novos dados a respeito das concentrações destes
elementos em órgãos de cetáceos marinhos ainda pouco
estudados, especialmente em uma região com
pouca informação como a porção oeste do Oceano Atlântico
Sul. Para tal, foram aplicados métodos analíticos
baseados
na técnica da espectrometria de absorção atômica (AAS),
utilizando a espectrometria de absorção atômica com forno
de
grafite (GF-AAS) e a espectrometria de absorção atômica
com
vapor frio (CVAAS), as mais frequentemente aplicadas para
a
determinação de elementos-traço e mercúrio
respectivamente,
em amostras biológicas. Estas técnicas apresentaram
ótima precisão e exatidão comprovadas através da análise
de
materiais de referência certificados (CRM) do National
Research Council - Canadá (DORM-2, DOLT-2 e TORT-2).
Foram
observadas diferenças regionais (região tropical e
subtropical) e inter-específicas (golfinhos de hábitos
costeiro e oceânico) sobre a acumulação dos elementos-
traço
e HgOrg nos órgãos estudados. As espécies de
hábito oceânico apresentaram as maiores concentrações
destes elementos em seus órgãos. O sexo dos indivíduos
não
influiu na bioacumulação dos elementos e
HgOrg. Os parâmetros população, comprimento total, e
maturidade sexual, influenciaram na acumulação dos
elementos-traço e HgOrg em ambos os órgãos, de
acordo com a espécie e a área de captura. S. guianensis,
co-
habita o mesmo ambiente que P. blainvillei, e
preferencialmente se alimenta de peixes maiores e
predadores, neste estudo, apresentou a razão molar de 1:1
entre o Se e o Hg,mostrando assim, que provavelmente o
processo de destoxificação de metilmercúrio hepático
esteja
ocorrendo. A espécie P. blainvillei se alimenta
preferencialmente de cefalópodes e peixes pequenos, e
apresentou uma razão molar de 4:1 entre o Se e o Hg no
fígado. Os metais de transição Cd e Ag, que
também interagem com o Se hepático nos mamíferos,
apresentaram correlações significativas no fígado dos
cetáceos marinhos estudados. A espécie S. guianensis
apresentou correlações significativas entre as
concentrações molares de Se e Cd (p = 0,01) e Se e Ag (p
<
0,001) no fígado. Para a espécie P. blainvillei, os
indivíduos provenientes de ambas as regiões (tropical e
subtropical) apresentaram correlações significativas
entre
as concentrações molares de Se e Hg (p < 0,001)
no fígado. Somente os indivíduos de P. blainvillei
capturados na região tropical apresentaram correlações
significativas entre as concentrações molares de Se e Cd
(p < 0,001). Não só as diferentes condições ambientais,
mas
também, o tempo de vida, o estágio de crescimento e,
principalmente a preferência alimentar,
influenciaram fortemente sobre a acumulação de elementos-
traço e HgOrg nos tecidos dos cetáceos assim como, sobre
suas inter-relações. / [en] The present work tested whether ecological and biological
parameters have an influence on the accumulation of trace
elements and organic mercury (HgOrg) by the liver and
kidney of coastal (Pontoporia blainvillei, N = 31; Sotalia
guianensis, N = 21) and oceanic (Stenella coeruleoalba, N =
3; Stenella frontalis, N = 4) cetaceans species
incidentally caught in fishing nets along two Brazilian
coastal areas (tropical - northern Rio de Janeiro State and
subtropical -Rio Grande do Sul State). This research added
new insight to the existing studies with trace element
concentrations in internal organs of marine cetaceans from
the southwestern Atlantic Ocean. Few studies have
documented trace element concentrations in marine mammals
in this area. Analytical methodologies based
on atomic absorption spectrometry (AAS), using the graphite
furnace (GF-AAS) and cold vapor (CV-AAS) techniques were
applied for this purpose. They are the most popular
analytical techniques applied for trace element and mercury
determination, respectively, in biological samples.
Precision and accuracy of the analytical methods were
determined and monitored using certified material from
National Research Council - Canada (DORM-2, DOLT-2 and TORT-
2). Interspecies (coastal and oceanic cetacean species) and
regional (tropical and subtropical regions) differences
were observed in the accumulation of trace
elements and organic mercury in organs, liver and kidney.
The highest concentrations of these elements were observed
in the liver of the oceanic cetacean species. However, no
gender differences were found on the
bioaccumulation of trace elements and also organic mercury.
Biological parameters such as, population, body length and
sexual maturity influenced on the trace element and organic
mercury accumulation by both organs, according to the
cetacean species and caught area. S. guianensis, which co-
habits the same coastal marine environment that P.
blainvillei species, was the only dolphin species that
presented a Se:Hg molar ratio close to 1:1, showing that a
probable detoxification process can be occurring in the
liver of S. guianensis. This dolphin species feeds
mainly on predatory fish, while P. blainvillei feeds mainly
on fish and cephalopods. P. blainvillei presented a Se:Hg
molar ratio close to 4:1. It`s known that transition
metals, such as Hg, Cd and Ag, have an interaction with Se
in the liver of marine mammals. The molar concentrations of
Cd (p = 0.01) and Ag (p < 0.001) presented significant
correlations with the hepatic molar Se in the liver of
S. guianensis. P. blainvillei from both sampling areas
presented a high significant correlation for molar Se to Hg
concentrations (p < 0.001) in liver. Meanwhile,
only individuals of P. blainvillei from tropical region
showed a significant correlation with hepatic Se and Cd (p
< 0.001). Based on the results present here,
it is possible to conclude that, not only the different
environmental conditions, but also life span, growth stage
but mainly the feeding habit influenced the
accumulation of trace elements and organic mercury by
cetacean tissues. These ecological and biological
parameters influenced on the inter-element relationships.
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Circulatory and Respiratory Responses to Cycle Ergometry at Different Pedal RatesHernandez, Raymundo 05 1900 (has links)
The effects of moderate workload exercise at different pedal rates on circulatory and respiratory parameters were studied. Five subjects performed seven discontinuous constant-load cycle ergometer tests of 30 minutes duration at pedal rates of 40, 50, 60, 70, 80, 90 and 100 rpm. Oxygen uptake and carbon dioxide production were determined by standard open circuit spirometry, while heart rate was recorded by electrocardiograph. The CO₂ rebreathing procedure was administered during the exercise bout in order to determine cardiac output. Blood pressure was determined for each test, and total peripheral resistance was calculated. The findings indicate that progressive increases in pedal frequency during discontinuous constant-load cycle ergometry produce progressive increases in cardiovascular, respiratory and metabolic responses and a decrease in gross exercise mechanical efficiency. The results indicate that oxygen uptake, cardiac output, heart rate, ventilation and arterial-venous oxygen difference increases curvilinearly as pedal rate increases, possibly as a result of increases in recruitment of muscle fibers and/or muscle groups. These findings suggest that circulatory and respiratory responses are due to "central command" which sets the basic efferent response pattern. However, this effector pattern is modulated by afferent input originating from the legs during progressive increases in pedal rate.
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Marqueurs oculomoteurs et neurphysiologiques de la régulation émotionnelle liée à l'attachement à l'adolescence / Oculomotor and neurophysiological markers of emotional regulation related to attachment in adolescenceSzymanska, Monika 12 December 2016 (has links)
Les changements pubertaires peuvent être à l'origine de multiples expériences socio-émotionnelles positives et/ou négatives que les adolescents doiven gérer. Le processus de la régulation émotionnelle (RE) va être grandement sollicité au cours de cette période. La littérature montre que la RE est une fonction psychobiologique dont le développement peut être impacté par divers facteurs environnementaux de l'enfance. Parmi ces facteurs, l'expérienc de l'attachement avec la figure d'attachement y joue un rôle primordial. Cependant, la question cruciale concernant l'impact de l'attachement sur les mécanismes comportementaux et neurophysiologiques des stratégies de RE à l'adolescence reste sous-estimée et les publications à ce sujet sont encore rares. Dans ce contexte, notre étude vise à détem1iner les paramètres oculomoteurs et neurophysiologiques pour les utiliser comme marqueurs potentiel des stratégies de régulation des émotions en fonction du style d'attachement chez les adolescents. Toutefois, la RE est difficilement évaluable avec des outils ne sollicitant que les processus cognitifs conscients des adolescents. À ce titre, il nous a paru nécessaire d'utiliser un dispositif d'eye-tracking synchronisé avec un système de mesure physiologique permet de déterminer les paran1ètres oculomoteurs et neurophysiologiques lors d'exploration des ces images. Cette étude soutient l'hypothèse que l'attachement module des paramètres oculomoteurs et neurophysiologiques des stratégies de la RE Ces résultats pourraient inciter à une nouvelle ligne de recherche afin de proposer une solution thérapeutique dans le contexte de la dysrégulation émotionnelle. / Adolescence is a time of increasing vulnerability to intemalizing and extemalizing psychopathologies associated with poor emotion regulation, including depression, anxiety and antisocial behavior. Emotion regulation is the ability to recrui processes to influence emotion generation. It is therefore important to understand how emotion regulation develops at thi time and how this relates to ongoing development in adolescence. In recent years there has been increasing interest in how attachment styles modulate emotion regulation strategies. However, few researches have addressed this question directly in adolescence. The crucial question conceming the behavioral and neurophysiological mechanisms ofregulatior strategies emotions in adolescence remains underestimated. Employing a specific, an ecologically valid paradigm, the current study determines the oculomotor and neurophysiologie patterns as a potential marker of emotion regulation strategies i.e., comfort and proximity seeking as a function ofattachment style in healthy adolescents. The Attachment Scale Interview was used to detennine attachment style (i.e., secure, fearful, enmeshed and avoidant) in eighty-one healthy adolescents. A synchronized eye-tracking and physiologie measurement device was used to determine gaze and neurophysiologie parameters, respectively, on attachment-related pictures issue from The BASP-Ado. Our results show the existence of different profiles of emotional regulation in adolescence. These results could encourage a new line of research in order to offer a therapeutic solution in the context of emotional dysregulation.
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