Sperm proteins in teleostean and chondrostean (sturgeon) fishes     

Li P  Hulak M  Linhart O 《Fish physiology and biochemistry》2009,35(4):567-581

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Growth and reproduction of the lion's paw scallop Nodipecten subnodosus in a suspended culture system at Guerrero Negro lagoon,Baja California Sur,Mexico     

Marcial Arellano‐Martínez  Bertha Patricia Ceballos‐Vázquez  César Ruíz‐Verdugo  Edgar Pérez de León  Rafael Cervantes‐Duarte  Pedro Martin Domínguez‐Valdéz 《Aquaculture Research》2011,42(4):571-582

The lion's paw scallop, Nodipecten subnodosus (Sowerby) has considerable aquacultural potential due to its fast growth and large adductor muscle. Prior investigations throughout northwestern Mexico's littoral have reported highly variable growth rates; furthermore, no studies are available of the environment on growth and gametogenesis in this species under culture conditions. This investigation assesses the effect of food availability and temperature on the growth and gametogenesis of N. subnodosus in a suspended culture system at Guerrero Negro lagoon, Mexico. After 1 year of cultivation, N. subnodosus reached 69.13 mm in shell height (SH) (0.196 mm day^?1, 14 months old). Two significant growth spurts were observed: over the two first months of culture (August and September 2001, mean growth rate 0.4 mm day^?1) and in September 2002 (0.3 mm day^?1), both related to high temperatures and chlorophyll a concentrations. The onset of gametogenesis occurred in April 2002, with an increase in temperature (10‐month‐old scallops, 54.5 mm SH). The first spawning occurred in October and November (86.2 and 93 mm SH), with peak temperatures. These results, together with the analysis of previous reports, indicate that N. subnodosus has a higher preference for temperate areas; therefore, the Guerrero Negro lagoon appears to be a suitable site to culture this species.  相似文献   

Degradation and effect of hydrogen peroxide in small‐scale recirculation aquaculture system biofilters     

Martin Sune Møller  Erik Arvin  Lars‐Flemming Pedersen 《Aquaculture Research》2010,41(8):1113-1122

From an environmental point of view, hydrogen peroxide (HP) has beneficial attributes compared with other disinfectants in terms of its ready degradation and neutral by‐products. The rapid degradation of HP can, however, cause difficulties with regard to safe and efficient water treatment when applied in different systems. In this study, we investigated the degradation kinetics of HP in biofilters from water recirculating aquaculture systems (RAS). The potential effect of HP on the nitrification process in the biofilters was also examined. Biofilter elements from two different pilot‐scale RAS were exposed to various HP treatments in batch experiments, and the HP concentration was found to follow an exponential decay. The biofilter ammonia and nitrite oxidation processes showed quick recuperation after exposure to a single dose of HP up to 30 mg L^?1. An average HP concentration of 10–13 mg L^?1 maintained over 3 h had a moderate inhibitory effect on the biofilter elements from one of the RAS with relatively high organic loading, while the nitrification was severely inhibited in the pilot‐scale biofilters from the other RAS with a relatively low organic loading. A pilot‐scale RAS, equipped with two biofilter units, both a moving‐bed (Biomedia) and a fixed‐bed (BIO‐BLOK^®) biofilter, was subjected to an average HP concentration of ～12 mg L^?1 for 3 h. The ammonium‐ and nitrite‐degrading efficiencies of both the Biomedia and the BIO‐BLOK^® filters were drastically reduced. The filters had not reverted to pre‐HP exposure efficiency after 24 h, suggesting a possible long‐term impact on the biofilters.  相似文献   

Morphological sex change upon treatment by endocrine modulators in meiogynogenetic tench (Tinca tinca L.)     

Martin Hulak  Martin Psenicka  David Gela  Marek Rodina  & Otomar Linhart 《Aquaculture Research》2010,41(2):233-239

Exogenous steroids alter sex differentiation in fish substantially. In the present study we have evaluated the effects of 17α-methyltestosterone (MT) and oestrogen receptor antagonist Tamoxifen (TA) on gonadal development and skewness of the sex ratio in all-female tench juveniles. In the first two experiments, sexually undifferentiated juveniles were orally treated with three doses of MT and TA (50, 100 and 150 mg kg⁻¹). Both the treatments resulted in a moderate dose-dependent masculinization, with neomale production ranging from 17% (50 mg kg⁻¹) to 26% (150 mg kg⁻¹) for the MT only treatment, and from 0% (50 mg kg⁻¹) to 27% (100 mg kg⁻¹) only for the TA treatment respectively. In the third experiment treatment of sexually differentiated tench females with single steroid treatments or combinations of the two resulted in populations composed of females and intersex individuals. The significantly highest occurrence of intersex individuals (45.5%) was found in the group subjected to combine treatment of MT+TA (150+200 mg kg⁻¹). No masculinization effect of the single or the combined treatment occurred. It can be concluded that oral treatment with MT or TA only slightly modifies the normal process of sex differentiation in gynogenetic tench juvenile, but treatment with the above-mentioned combinations has a highly significant potential to skew the sex ratio in sexually differentiated tench females. However, from an applied point of view, the treatment procedure will need optimization before use at a commercial level.  相似文献   

Sectional notes     

A. G. Tolaas  E. L. Newdick  R. A. Jehle  Ralph W. Donaldson  Robert Schmidt  H. O. Werner  J. R. Liv-Ermore  William H. Martin  J. B. R. Dickey  Harold L. Bailey  E. B. Tussing  G. S. Ralston  Chas D. Gaines  John Tucker 《American Journal of Potato Research》1934,11(10):276-287

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Sectional notes     

H. W. Poulsen  H. G. Zuckerman  C. H. Metzger  W. B. Ward  W. C. Edmundson  E. R. Bennet  R. A. Jehle  A. B. Beaumont  John S. Gardner  E. L. Newdick  Frank W. Hussey  E. J. Wheeler  H. C. Moore  Marx Koehnke  A. G. Tolaas  E. E. Isaac  H. O. Werner  O. Butler  William H. Martin  K. H. Fernow  E. R. Jackman  E. B. Tussing  E. V. Hardenburg  J. B. R. Dickey  K. H. Klages  G. S. Ralston  H. L. Bailey  John Tucker 《American Journal of Potato Research》1934,11(8):207-226

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Potato meeting     

Wm. H. Martin  H. T. Gussow  Karl H. Fernow  H. Werner  J. E. Currey 《American Journal of Potato Research》1926,3(5):174-176

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Determination of soil properties using thermogravimetry under laboratory conditions     

Ji&#x;í Ku erík  Karel Svato&#x;  Stanislav Malý  Martin Brtnický  Helena Dolealov‐Weismannov  Michael S. Demyan  Christian Siewert  David Tokarski 《European Journal of Soil Science》2020,71(3):415-419

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Electrokinetic-enhanced remediation of actual arsenic-contaminated soils with approaching cathode and Fe0 permeable reactive barrier     

Yao  Weikang  Cai  Zongping  Sun  Shuiyu  Romantschuk  Martin  Sinkkonen  Aki  Sun  Yan  Wang  Qiang 《Journal of Soils and Sediments》2020,20(3):1526-1533

Purpose

The aim of this study was to investigate the remediation efficiency of actual arsenic-contaminated soils by electrokinetic (EK)-enhanced remediation with approaching cathode and Fe⁰ permeable reactive barrier (PRB).

Materials and methods

Experiments were conducted in a lab-made apparatus consisting of the anode reservoir, the soil specimen chamber, and the cathode reservoir.

Results and discussion

In this study, the enhanced combination methods (approaching cathode and Fe⁰-PRB) were assisted for EK remediation of actual arsenic-contaminated soils under a voltage gradient of 1 V/cm and a treatment period of 96 h. Experimental results showed that arsenic accumulated in the anode sections (I, II) of the soil by employing EK alone with an arsenic removal rate of less than 5%. In contrast, EK-enhanced remediation with either approaching cathode (EK/AC) or Fe⁰-PRB (EK/PRB) reduced the arsenic concentrations in both central and anode sections of the soil and afforded the removal rates of 20% in both cases. However, EK-enhanced remediation with the combination of approaching cathode and Fe⁰-PRB (EK/PRB/AC) reached the removal efficiency of 45% without arsenic accumulation in any soil sections. This phenomenon is mainly caused by the approaching cathode that creates an alkaline environment to promote the migration of arsenic, as well as PRB filled with Fe⁰ that achieves the adsorption and immobilization of arsenic.

Conclusions

The highest remediation efficiency was achieved in the EK/PRB/AC test, which was attributed to the fact that the combination of this two methods solved the problem of arsenic accumulation in treated soil and ensured a more thorough arsenic removal. Furthermore, enhanced remediation efficiency does not elevate the costs.

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Uniform seed potato certification standards     

Wm. H. Martin 《American Journal of Potato Research》1933,10(12):245-248

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