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1.
Jerzy Szwagrzyk Zbigniew Maciejewski Ewa Maciejewska Andrzej Tomski Anna Gazda 《Annals of Forest Science》2018,75(3):80
Key message
The disturbance of a research plot by a windstorm allowed us to study the role of the seedling bank in the regeneration processes. The released advance regeneration dominated among the saplings; taller individuals retained their position until the end of the study. Pioneer species occurred sporadically. Seven years after the disturbance, the windthrow was covered by a dense thicket of young trees.Context
The dominant role played by advance regeneration in natural regeneration processes after intense wind disturbances is still a matter of dispute.Aims
We took advantage of a windstorm in one of our research plots to study the role of the seedling bank released by the disturbance in the regeneration processes.Methods
We collected data in 70 plots, recording the survivorship of seedlings, annual height growth, and signs of browsing. The height ranking was analyzed with Kendall’s concordance coefficient, and the height growth rates were compared using Dunn’s test.Results
The density of seedlings increased from 6.7/m2 in 2008 to 8.1/m2 in 2010 and then decreased to 1.2/m2 in 2015. The density of saplings increased continuously from 0.14 to 1.9/m2. The highest size differentiation occurred in sycamore maple; the individuals which were taller before the windstorm retained their position until the year 2015. The only species that was recruited mainly from germinants was European hornbeam.Conclusion
The advance regeneration released by the windstorm played a major role in the regeneration process, while pioneer species occurred only sporadically. Seven years after the disturbance, the windthrow was already covered by a dense thicket of young trees.2.
Participation of phosphofructokinase,malate dehydrogenase and isocitrate dehydrogenase in capacitation and acrosome reaction of boar spermatozoa
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E Breininger D Dubois VE Pereyra PC Rodriguez MM Satorre PD Cetica 《Reproduction in domestic animals》2017,52(5):731-740
The aim of this work was to determine the enzymatic activity of phosphofructokinase (PFK), malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) in boar spermatozoa and study their participation in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction. Enzymatic activity of these enzymes was determined spectrophotometrically in extracts of boar spermatozoa. Sperm suspensions were incubated in the presence of bicarbonate (40 mM), a well‐known capacitation inducer, or follicular fluid (30%), as an acrosome reaction inducer, and different concentrations of oxoglutarate, oxalomalate and hydroxymalonate, inhibitors of PFK, IDH and MDH, respectively. Capacitation percentages were determined by the fluorescence technique of chlortetracycline (CTC), and true acrosome reaction was determined by trypan blue and differential–interferential contrast, optical microscopy. The activity of PFK in boar spermatozoa enzymatic extracts was 1.70 ± 0.19 U/1010 spermatozoa, the activity of NAD‐ and NADP‐dependent IDH was 0.111 ± 0.005 U/1010 and 2.22 ± 0.14 U/1010 spermatozoa, respectively, and the activity of MDH was 4.24 ± 0.38 U/1010 spermatozoa. The addition of the specific inhibitors of these enzymes prevented sperm capacitation and decreased sperm motility during capacitation and inhibited the acrosome reaction (AR), without affecting the sperm motility during this process. Our results demonstrate the participation of PFK, IDH and MDH in bicarbonate‐induced capacitation and follicular fluid‐induced acrosome reaction in boar spermatozoa, contributing to elucidate the mechanisms that produce energy necessary for these processes in porcine spermatozoa. 相似文献
3.
This paper presents the results of a research project concerning bark beetle populations in Norway spruce stands managed under a nature protection regime in national parks in Tatra Mountains in Poland and Slovakia. The preliminary data on bark beetle occurrence and related selected stand characteristics are presented. The dynamics of a bark beetle outbreak that occurred from 1994–97 in the stands localized on both sides of the state border and in various nature protection regimes is analyzed retrospectively. The data concerning the tree/stand characteristics, i.e. DBH and increment of trees are discussed in relation to its potential role in the mechanism for the spread of bark beetle populations. The patterns of the spatial distribution of trees attacked during the research period (1999–2001) are described. 相似文献
4.
5.
The Influence of Maca (<Emphasis Type="Italic">Lepidium meyenii</Emphasis>) on Antioxidant Status,Lipid and Glucose Metabolism in Rat 总被引:1,自引:0,他引:1
Vecera R Orolin J Skottová N Kazdová L Oliyarnik O Ulrichová J Simánek V 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(2):59-63
This work focused on the effect of maca on lipid, anti-oxidative, and glucose parameters in hereditary hypertriglyceridemic
(HHTg) rat. Maca (1%) was administred to rats as a part of a high-sucrose diet (HSD) for 2 weeks. Rosiglitazone (0.02%) was
used as a positive control. Maca significantly decreased the levels of VLDL (very low density lipoproteins), LDL (low density
lipoproteins), and total cholesterol, and also the level of TAG (triacylglycerols) in the plasma, VLDL, and liver. Maca, as
well as rosiglitazone, significantly improved glucose tolerance, as the decrease of AUC (area under the curve) of glucose
showed, and lowered levels of glucose in blood. The activity of SOD (superoxide dismutase) in the liver, the GPX (glutathione
peroxidase) in the blood, and the level of GSH (glutathione) in liver increased in all cases significantly. Results demonstrate
that maca seems to be promising for a positive influence on chronic human diseases (characterized by atherogenous lipoprotein
profile, aggravated antioxidative status, and impaired glucose tolerance), and their prevention. 相似文献
6.
This paper presents the results of a research project concerning bark beetle populations in Norway spruce stands managed under a nature protection regime in national parks in Tatra Mountains in Poland and Slovakia. The preliminary data on bark beetle occurrence and related selected stand characteristics are presented. The dynamics of a bark beetle outbreak that occurred from 1994–97 in the stands localized on both sides of the state border and in various nature protection regimes is analyzed retrospectively. The data concerning the tree/stand characteristics, i.e. DBH and increment of trees are discussed in relation to its potential role in the mechanism for the spread of bark beetle populations. The patterns of the spatial distribution of trees attacked during the research period (1999–2001) are described. 相似文献
7.
Sanchez-Ortiz A Romero-Segura C Gazda VE Graham IA Sanz C Perez AG 《Journal of agricultural and food chemistry》2012,60(5):1300-1307
The aim of the present work was to establish the limiting factors affecting the biosynthesis of volatile esters present in virgin olive oil (VOO). Oil volatile fractions of the main Spanish olive cultivars, Arbequina and Picual, were analyzed. It was observed that acetate esters were the most abundant class of volatile esters in the oils, in concordance with the high content of acetyl-CoA found in olive fruit, and that the content of C6 alcohols is limited for the synthesis of volatile esters during the production of VOO. Thus, the increase of C6 alcohol availability during VOO production produced a significant increase of the corresponding ester in the oils in both cultivars at two different maturity stages. However, the increase of acetyl-CoA availability had no effect on the VOO volatile fraction. The low synthesis of these C6 alcohols seems not to be due to a shortage of precursors or cofactors for alcohol dehydrogenase (ADH) activity because their increase during VOO production had no effect on the C6 alcohol levels. The experimental findings are compatible with a deactivation of ADH activity during olive oil production in the cultivars under study. In this sense, a strong inhibition of olive ADH activity by compounds present in the different tissues of olive fruit has been observed. 相似文献
8.
Teker Tuğba Sefer Özlem Gazdağlı Aylin Yörük Emre Varol Gülin İnci Albayrak Gülruh 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(3):611-622
European Journal of Plant Pathology - Specific mechanisms contributing to the antifungal activity of α-thujone, one of the main compounds of essential oils in herbs, against Fusarium... 相似文献
9.
Szwagrzyk Jerzy Gazda Anna Zwijacz-Kozica Tomasz Zięba Antoni Ciesielska Barbara Szewczyk Janusz Foremnik Kacper Muter Elżbieta Bodziarczyk Jan 《European Journal of Forest Research》2021,140(4):835-845
European Journal of Forest Research - The relative importance of environmental factors and species pool in natural regeneration processes is still intensively disputed. Is environmental filtering... 相似文献
10.
Marcin K. Dyderski Anna Gazda Mariusz Hachułka Paweł Horodecki Izabela L. Kałucka Jacek Kamczyc Marek Malicki Remigiusz Pielech Michał Smoczyk Maciej Skorupski Sylwia Wierzcholska Andrzej M. Jagodziński 《Annals of Forest Science》2018,75(4):91