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Olesya I. Zhuravleva Alexandr S. Antonov Vo Thi Dieu Trang Mikhail V. Pivkin Yuliya V. Khudyakova Vladimir A. Denisenko Roman S. Popov Natalya Y. Kim Ekaterina A. Yurchenko Andrey V. Gerasimenko Anatoly A. Udovenko Gunhild von Amsberg Sergey A. Dyshlovoy Shamil S. Afiyatullov 《Marine drugs》2021,19(1)
Seven new deoxyisoaustamide derivatives (1–7) together with known compounds (8–10) were isolated from the coral-derived fungus Penicillium dimorphosporum KMM 4689. Their structures were established using spectroscopic methods, X-ray diffraction analysis and by comparison with related known compounds. The absolute configurations of some alkaloids were determined based on CD and NOESY data as well as biogenetic considerations. The cytotoxic and neuroprotective activities of some of the isolated compounds were examined and structure-activity relationships were pointed out. New deoxyisoaustamides 4–6 at concentration of 1 µM revealed a statistical increase of PQ(paraquat)-treated Neuro-2a cell viability by 30–39%. 相似文献
13.
Indicators of success for smart law enforcement in protected areas: A case study for Russian Amur tiger (Panthera tigris altaica) reserves 下载免费PDF全文
Michiel H. H. HÖTTE Igor A. KOLODIN Sergei L. BEREZNUK Jonathan C. SLAGHT Linda L. KERLEY Svetlana V. SOUTYRINA Galina P. SALKINA Olga Y. ZAUMYSLOVA Emma J. STOKES Dale G. MIQUELLE 《Integrative zoology》2016,11(1):2-15
Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART, measures of success are ill‐defined and, to date, few reports detail results post‐implementation. Here, we present 4 case studies from protected areas with Amur tigers (Panthera tigris altaica) in Russia, in which indicators of success were defined and evaluated at each. The ultimate goal was an increase in tiger numbers to 1 individual/100 km2 at each site. We predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and, subsequently, tiger numbers. We used short‐term and long‐term indicators of success, including: (i) patrol team effort and effectiveness; (ii) catch per unit effort indicators (to measure reductions in threats); and (iii) changes in target species numbers. In addition to implementing a monitoring system, we focused on improving law enforcement management using an adaptive management process. Over 4 years, we noted clear increases in patrol effort and a partial reduction in threats. Although we did not detect clear trends in ungulate numbers, tiger populations remained stable or increased, suggesting that poaching of tigers may be more limiting than prey depletion. Increased effectiveness is needed before a clear reduction in threats can be noted, and more time is needed before detecting responses in target populations. Nonetheless, delineation of concrete goals and indicators of success provide a means of evaluating progress and weaknesses. Such monitoring should be a central component of law enforcement strategies for protected areas. 相似文献
14.
Nutrient efficacy of microalgae as aquafeed additives for the adult black tiger prawn,Penaeus monodon 下载免费PDF全文
Yan Li Guoqiang Xiao Arnold Mangott Megan Kent Igor Pirozzi 《Aquaculture Research》2016,47(11):3625-3635
This study used a small amount of several lyophilized microalgae (5% of dry weight in aquafeed) to feed adult black tiger prawns Penaeus monodon for 4 weeks, aiming to promote prawn health and nutritional level. Apart from slight increases in ash content, chlorophyll and β‐carotene in the microalgae‐added feeds, there was no difference from the commercial diet in their biochemical composition. After 28 days of feeding, prawn body length, body weight, condition index and also total amount of fatty acids and amino acids of the flesh (2nd abdominal segment) were not affected by microalgae additives as compared with the control commercial diet‐fed group (P > 0.05). Prawns fed the microalgae diets, however, had a relatively better survival rate than those fed the commercial control diet, although no statistical significance was detected in any except for the diatom Melosira sp. The elevated survival rate was concomitant with a higher phagocytosis rate and superoxide dismutase (SOD) activity in the immune response analysis, and significantly a higher astaxanthin content detected in the tail muscle of microalgae diet‐fed prawns (5.36–10.78 ng of astaxanthin per gram of muscle DW). These findings demonstrated that low‐inclusion microalgal additives in prawn diets over a short feeding period (4 weeks) can result in healthier adult prawn, and hence could contribute to the development of an optimized feeding strategy for prawn aquaculture close to harvesting. 相似文献
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Elina Nafikova Irina Mironova Igor Gazeev Dmitry Blagov Azat Nigmatiyanov 《Canadian journal of veterinary research》2021,85(3):210
The objective of this study was to determine the effect of an energy additive on the metabolism of cattle. This article provides information on the analysis of the diet of young cattle calculated for when the animals were both indoors and outdoors. The ration was prepared for 40 heifers, divided into 4 groups consisting of 10 animals in each group. Three of these groups were fed different amounts of a high-energy additive, which was not fed to the control group. The effectiveness of the additive was analyzed according to the balance experiment and by calculating digestibility coefficients. It was determined that the percentage of nitrogen use in young animals was higher in the groups that were fed the additive than in the control group. Increasing the dose of the additive increased the level of nitrogen use. Comparative analysis of live weight indicated intergroup differences in favor of heifers in the groups that were fed the additive of 1.34% to 2.41% at the age of 9 mo; 2.51% to 4.16% at 12 mo; 3.14% to 5.46% at 15 mo; and 3.57% to 6.30% at 18 mo. The average daily growth dynamics indicated a gradual increase in all animals up to 15 mo, with a slight decrease by 18 mo of age. The difference among the groups ranged from 5.08% to 8.85% at 6 to 9 mo of age; 7.08% to 10.79% at 9 to 12 mo; 5.64% to 10.97% at 12 to 15 mo; and 6.05% to 11.11% at 18 mo. It was concluded that feeding the energy additive Tanrem to heifers increased their metabolism so that nitrogen use was improved, and feed was digested more efficiently, which in turn improved the growth of animals. Using an energy additive at the mid-range dose of 500 g a day per animal is recommended, since the effect was similar at the mid-range and maximum dosages. 相似文献
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RAPD analysis of interspecific relationships in presumably apomictic Cotoneaster species 总被引:3,自引:0,他引:3
A few of the approximately 300 Cotoneaster species described are diploid but the majority appear to be polyploid. The occurrence of apomixis inpolyploid Cotoneaster species has been reported but never proven with genetic markers. We have used 76 polymorphic RAPD markers to investigate
the breeding system and phenetic grouping of some critical taxa, including a total of 19 plant accessions representing 13
mostly European species in the series Cotoneaster. Three to four individual plants, raised from seed from the same original plant, were analyzed for each of three accessions
to investigate the possible occurrence of apomictic seed set. Absolutely congruent RAPD profiles were encountered among seedlings
from one accession, whereas we found one or two marker differences among seedlings from the other two accessions. Genetic
similarities among the different accessions were analyzed with a UPGMA-derived dendrogram. The most deviant taxon was the
Chinese C. albokermesinus. A group withC. soczavianus and C. tomentosus was rather isolated from the remainder, as was also C. kullensis. Among the remaining taxa, two well supported clusters were found: (1) C. antoninae and C. uralensis, and (2) C. integerrimus and C. raboutensis, whereas the other five species (C. canescens, C. niger, C. scandinavicus, C. juranus, C. cambricus) formed a poorly supported cluster with no clear substructuring. A principal coordinate analysis yielded results that were
in good correspondence with the dendrogram. Again C. albokermesinus appears to be totally isolated from the other species. In addition, two well-defined and rather isolated groups were found:
(1) C. tomentosus and C. soczavianus, and (2) C. antoninae and C. uralensis, with the remainder comprising a loosely defined group.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Igor Grebenščikov 《Genetic Resources and Crop Evolution》1985,33(2):183-198
Zusammenfassung Im Laufe von 16 Jahren (1968–1983) wurden für Rohproteinanalysen des Korns aus dem Gaterslebener Maissortiment zufällige Stichproben von etwa 40 bis 80 Stämmen jährlich entnommen. Für die Mittelwerte und Varianzen der Stichproben wurden die 95 %-Vertrauensbereiche geschätzt (Abb. 1 und 3). Die meisten Jahresmittelwerte für den Gehalt an Rohprotein (RP %) liegen zwischen 11,4 und 12,1 % (ohne Puff- und Zuckermais). Signifikante Abweichungen wurden nur selten beobachtet. Die jährlichen Variabilitätskoeffizienten liegen hier bei etwa 12 %, bei vielen anderen Merkmalen dagegen um 30 %. Die Schätzung der Korrelation zwischen RP % und TKM im Durchschnitt von 13 Jahren (wieder ohne Puff- und Zuckermaise) ergab einen nicht signifikanten Wert vonr
s
=-0,04. Ferner wurden zahlreiche Varianzanalysen (Modell II) mit Schätzung von Varianzkomponenten (auch in %) für die Faktoren Stamm und Jahr durchgeführt, die dafür sprechen, daß für eine befriedigende Erfassung von RP %-Variabilität 3 bis 4 Kolben je Stamm in 3 bis 4 Jahren nötig sind. Am Schluß sind 40 Gaterslebener Sortimentsnummern mit mindestens vierjährigen Rohprotein-Mittelwerten über 12 % und den dazugehörigen 95 %-Vertrauensbereichen angeführt.
Variability of the curde protein content in the Gatersleben maize collection
Summary Random samples of a number between 40 and 80 strains out of the Gatersleben maize collection were taken every of 16 years (1968–1983) for analyses of grain crude protein. For both means and variances, 95 % confidence intervals were estimated (Figs. 1 and 3). Most of the annual means of the crude protein content are between 11.4 and 12.1 per cent (except pop and sweet corn). Significant deviations were only seldom observed. The annual coefficients of variability are here around 12 %, whereas those of many other characters are around 30 %. For the correlation between crude protein content and thousand grain weight for an average of 13 years (again except pop and sweet corn), a non-significant value of r s =–0.04 was estimated. Furthermore, numerous analysis of variance (Model II) were made, with estimation of the components of variance (also in per cent) for the factors strain and year. They suggest that 3 to 4 ears per strain for every of 3 to 4 years are necessary, in order to ascertain satisfactorily the variability of the crude protein content. Finally, 40 strains of the Gatersleben collection are listed, which gave crude protein means above 12 % for at least four years; the corresponding 95 % confidence intervals are included.
16 (1968–1983) 40 80 . 95 %- (. 1 3). ( %) 11,4 12,1 % ( ). . ( 12 %), 30 %. % 1000 13 (. =–0,04). ( ) () , % 3 4 3–4 . 40 »« , 12 % ( 4-) 95 %- .相似文献
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Bouchard LS Burt SR Anwar MS Kovtunov KV Koptyug IV Pines A 《Science (New York, N.Y.)》2008,319(5862):442-445
Catalysis is vital to industrial chemistry, and the optimization of catalytic reactors attracts considerable resources. It has proven challenging to correlate the active regions in heterogeneous catalyst beds with morphology and to monitor multistep reactions within the bed. We demonstrate techniques, using magnetic resonance imaging and para-hydrogen (p-H2) polarization, that allow direct visualization of gas-phase flow and the density of active catalyst in a packed-bed microreactor, as well as control over the dynamics of the polarized state in space and time to facilitate the study of subsequent reactions. These procedures are suitable for characterizing reactors and reactions in microfluidic devices where low sensitivity of conventional magnetic resonance would otherwise be the limiting factor. 相似文献