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1.
Acta Biol Hung ; 63(2): 268-76, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22695524

RESUMO

The main function of the Kis-Balaton Water Protection System is to retain nutrients and total suspended solids, thus protecting the water quality of Lake Balaton. In this paper, the toxic nature of the sediment in the 2nd reservoir of the KBWPS has been characterised, using a battery of tests: Vibrio fischeri acute bioassay on whole sediment samples, and V. fischeri bioassay on pore water and elutriate samples. The latest version of the V. fischeri bioluminescence inhibition was applied, the Flash assay which uses a kinetic mode and is able to detect the toxicity of solid, turbid/coloured samples. Whole sediment toxicity showed a clear spatial distribution of toxicity, in parallel with elutriate toxicity. However, no pore water toxicity was detected, leading to the conclusion that contaminants are not water soluble.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Aliivibrio fischeri , Hungria , Lagos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Qualidade da Água
2.
Anim Reprod Sci ; 235: 106890, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34847527

RESUMO

Interest in the use of assisted reproductive technology in reindeer husbandry has gradually increased during the last decades. This article reviews Western and Russian literature on reindeer semen collection, semen cryopreservation and artificial insemination. In addition, literature on the synchronisation of the stage of reindeer oestrous cycle among females, recovery of in vivo embryos, embryo transfer, the production of in vitro-produced embryos and pregnancy diagnosis is reviewed.


Assuntos
Prenhez , Rena , Técnicas de Reprodução Assistida/veterinária , Animais , Criopreservação/veterinária , Transferência Embrionária/veterinária , Ciclo Estral , Feminino , Inseminação Artificial/veterinária , Masculino , Gravidez , Sêmen , Manejo de Espécimes/veterinária
3.
Anim Reprod Sci ; 227: 106722, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33621844

RESUMO

The present review provides a comprehensive assessment on the basic aspects of the reproduction of the Rangifer male with a special focus on pubertal development, and the seasonal dynamics of gametogenesis, androgenesis, antler cycle and other physiological and behavioural characteristics of the rutting male. A greater understanding of the reproductive physiology of the males is needed to improve existing management strategies of semi-domestic stocks in the changing climate and to develop species-specific assisted reproductive technologies for improving the in situ and ex situ conservation programs to preserve endangered subspecies as well as to facilitate the transfer of genetic resources between fragmented wild or semi-domestic populations.


Assuntos
Rena/fisiologia , Reprodução/fisiologia , Animais , Masculino
4.
Rev Sci Instrum ; 91(9): 093202, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33003790

RESUMO

We report on cyclotron frequency measurements on trapped 206,207Pb+ ions by means of the non-destructive Fourier-transform ion-cyclotron-resonance technique at room temperature. In a proof-of-principle experiment using a quartz crystal instead of a coil as a resonator, we have alternately carried out cyclotron frequency measurements for 206Pb+ and 207Pb+ with the sideband coupling method to obtain 21 cyclotron-frequency ratios with a statistical uncertainty of 6 × 10-7. The mean frequency ratio R¯ deviates by about 2σ from the value deduced from the masses reported in the latest Atomic Mass Evaluation. We anticipate that this shift is due to the ion-ion interaction between the simultaneously trapped ions (≈100) and will decrease to a negligible level once we reach single-ion sensitivity. The compactness of such a crystal makes this approach promising for direct Penning-trap mass measurements on heavy and superheavy elements.

5.
Anim Reprod Sci ; 70(3-4): 283-6, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11943498

RESUMO

The effect of gelatin addition to the semen extender on the viability and acrosome integrity of rabbit spermatozoa was studied. Pooled semen samples were processed in a boar semen extender with or without gelatin addition. Semen samples were stored at 5 degrees C for 72 h. Viability and acrosome integrity was evaluated by light microscope. Results showed that gelatin addition had a significant positive effect on the quality of the stored semen.


Assuntos
Acrossomo/fisiologia , Gelatina/administração & dosagem , Coelhos , Espermatozoides/fisiologia , Animais , Sobrevivência Celular , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Espermatozoides/ultraestrutura
6.
Biotech Histochem ; 77(3): 117-20, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12229931

RESUMO

Determination of the percentage of live cells with intact acrosomes and no morphologic aberrations could be a practical index of semen quality. We applied viability and acrosome staining techniques, originally described for bull, boar and rabbit sperm, to mouse spermatozoa. The viability stain was either trypan blue or Congo red. The stain was precipitated by neutral red in the fixative. The acrosome was stained by Giemsa. Sperm morphology, including cytoplasmic droplets, could be evaluated as well. The staining method described here is a useful routine tool for simultaneous evaluation of the plasma membrane integrity of different sperm subdomains, the status of the acrosome, and cellular morphology.


Assuntos
Acrossomo , Espermatozoides/citologia , Coloração e Rotulagem , Azul Tripano , Acrossomo/fisiologia , Animais , Sobrevivência Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espermatozoides/fisiologia
7.
Phys Rev Lett ; 96(16): 163004, 2006 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-16712224

RESUMO

A high-accuracy mass measurement of 7Li was performed with the SMILETRAP Penning-trap mass spectrometer via a cyclotron frequency comparison of 7Li3+ and H2+. A new atomic-mass value of 7Li has been determined to be 7.016 003 425 6(45) u with a relative uncertainty of 0.63 ppb. It has uncovered a discrepancy as large as 14sigma (1.1 microu) deviation relative to the literature value given in the Atomic-Mass Evaluation AME 2003. The importance of the improved and revised 7Li mass value, for calibration purposes in nuclear-charge radii and atomic-mass measurements of the neutron halos 9Li and 11Li, is discussed.

8.
Phys Rev Lett ; 92(11): 112501, 2004 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-15089126

RESUMO

Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations.

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