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991.
Pablo Sastre Carlos Ponce Carlos Palacín Carlos A. Martín Juan C. Alonso 《European Journal of Wildlife Research》2009,55(4):425-432
We investigated the effects of human activities on the behaviour of great bustards (Otis tarda) in a Special Protection Area in central Spain. We recorded 532 disturbances, at a rate of 0.93 disturbances per hour, a
high value compared to other studies. Escape (flight/running) was observed more often than alert. Flight was more frequent
than running. Car traffic and walkers were the main sources of disturbance. Motorcyclists, dogs, helicopters and aeroplanes
were also harmful in relation to their abundance and time of permanence. Farming and shepherding produced few disturbances
and usually did not cause a flight response. These activities are thus considered compatible with the conservation of the
great bustards. Hunting caused an increase in the frequency of disturbance on weekends and holidays with respect to working
days. We propose access restrictions to car traffic and helicopters/airplanes and hunting limitations in those areas more
frequently used by the species.
Pablo Sastre and Carlos Ponce Cabas contributed equally to this work. 相似文献
992.
P450 BM3 mutant can catalyze indole to indoxyl, and indoxyl can dimerize to form indigo. But the reaction catalyzed by P450
BM3 requires NADPH, as coenzyme regeneration is very important in this system. As we know, when glucose dehydrogenase oxidizes
glucose to glucolactone, NADH or NADPH can be formed, which can contribute to NADPH regeneration in the reaction catalyzed
by P450 BM3. In this paper, a recombinant Escherichia coli BL21 (pET28a (+)-P450 BM3-gdh0310) was constructed to co-express both P450 BM3 gene and glucose dehydrogenase (GDH) gene.
To improve the expression level of P450 BM3 and GDH in E. coli and to avoid the complex and low-efficiency refolding operation in the purification procedure, the expression conditions
were optimized. Under the optimized conditions, the maximum P450 BM3 and GDH activities amounted to 8173.13 and 0.045 U/mg
protein, respectively. Then bioconversion of indole to indigo was carried out by adding indole and glucose to the culture
after improved expression level was obtained under optimized conditions, and 2.9 mM (760.6 mg/L) indigo was formed with an
initial indole concentration of 5 mM. 相似文献
993.
994.
Differentiation of embryonic stem cell (ESC)-derived embryoid bodies (EBs) is a heterogeneous process. ESCs can differentiate
in vitro into different cell types including beating cardiomyocytes. The main aim of the present study was to develop an improved
preparation method for scanning electron microscopic study of ESC-derived cardiac bundles and to investigate the fine structural
characteristics of mouse ESCs-derived cardiomyocytes using electron microscopy. The mouse ESCs differentiation was induced
by EBs’ development through hanging drop, suspension and plating stages. Cardiomyocytes appeared in the EBs’ outgrowth as
beating clusters that grew in size and formed thick branching bundles gradually. Cardiac bundles showed cross striation even
when they were observed under an inverted microscope. They showed a positive immunostaining for cardiac troponin I and α-actinin.
Transmission and scanning electron microscopy (TEM & SEM) were used to study the structural characteristics of ESC-derived
cardiomyocytes. Three weeks after plating, differentiated EBs showed a superficial layer of compact fibrous ECM that made
detailed observation of cardiac bundles impossible. We tried several preparation methods to remove unwanted cells and fibers,
and finally we revealed the branching bundles of cardiomyocytes. In TEM study, most cardiomyocytes showed parallel arrays
of myofibrils with a mature sarcomeric organization marked by H-bands, M-lines and numerous T-tubules. Cardiomyocytes were
connected to each other by intercalated discs composed of numerous gap junctions and fascia adherences. 相似文献
995.
Thlaspi caerulescens L. is well known as a Zn/Cd hyperaccumulator. The genetic manipulation of T. caerulescens through transgenic technology can modify plant features for use in phytoremediation. Here, we describe the efficient transformation of T. caerulescens using Agrobacterium tumefaciens strain EHA105 harboring a binary vector pBI121 with the nptII gene as a selectable marker, the gus gene as a reporter and a foreign catalase gene. Based on the optimal concentration of growth regulators, the shoot cluster regeneration system via callus phase provided the basis of the genetic transformation in T. caerulescens. The key variables in transformation were examined, such as co-cultivation period and bacterial suspension density. Optimizing factors for T-DNA delivery resulted in kanamycin-resistant transgenic shoots with transformation efficiency more than 20%, proven by histochemical GUS assay and PCR analysis. Southern analysis of nptII and RT-PCR of catalase gene demonstrated that the foreign genes were integrated in the genome of transformed plantlets. Moreover, the activity of catalase enzyme in transgenic plants was obviously higher than in wild-type plants. This method offers new prospects for the genetic engineering of this important hyperaccumulator species. 相似文献
996.
Jisung Jang Sook Hee Yoon Wonseok Lee Jihyun Yu Joon Yoon Seunghyun Shim Heebal Kim 《Genes & genomics.》2018,40(8):825-834
Porcine epidemic diarrhea virus (PEDV), the causative agent of porcine epidemic diarrhea (PED), has led to tremendous economic losses in the global swine industry. Although the phylogeny of PEDV has been investigated extensively at the molecular level, there was no time-calibrated phylogenomic study on the virus. To improve insight into this topic, we analyzed 138 published genome sequences using the Bayesian coalescent analyses as well as Bayesian inferences and maximum likelihood methods. All of the global PEDV isolates were divided into six groups, except for one unclassified isolate. Of the six groups, Groups 1–5 comprised pandemic viruses while the remaining Group 6 contained classical isolates. Interestingly, the two clades, both pandemic and classical, consisted of clade-specific amino acid sequences in five genes: ORF1a, ORF1b, S, ORF3, and N. Within the pandemic clade, Group 1 and Group 2 originated from North America, whereas Group 3–Group 5 were derived from Asia. In Group 2, there was a common origin of S INDEL isolates. Within each group, there was no apparent association between temporal or geographic origin and heterogeneity of PEDVs. Our findings also showed that the PEDV virus evolved at a rate of 3.38?×?10?4 substitutions/site/year, and the most recent common ancestor of the virus emerged 75.9 years ago. Our Bayesian skyline plot analysis indicated that the PEDV had maintained constant effective population size excluding only a short period, around 2012, when a valley shaped decline in the effective number of infections occurred. 相似文献
997.
Marine bacteria have recently attracted attention as potentially useful candidates for the production of practical materials
from marine ecosystems, including the oceanic carbon dioxide cycle. The advantages of using marine bacteria for the biosynthesis
of poly(hydroxyalkanoate) (PHA), one of the eco-friendly bioplastics, include avoiding contamination with bacteria that lack
salt-water resistance, ability to use filtered seawater as a culture medium, and the potential for extracellular production
of PHA, all of which would contribute to large-scale industrial production of PHA. A novel marine bacterium, Vibrio sp. strain KN01, was isolated and characterized in PHA productivity using various carbon sources under aerobic and aerobic–anaerobic
marine conditions. The PHA contents of all the samples under the aerobic–anaerobic condition, especially when using soybean
oil as the sole carbon source, were enhanced by limiting the amount of dissolved oxygen. The PHA accumulated using soybean
oil as a sole carbon source under the aerobic–anaerobic condition contained 14% 3-hydroxypropionate (3HP) and 3% 5-hydroxyvalerate
(5HV) units in addition to (R)-3-hydroxybutyrate (3HB) units and had a molecular weight of 42 × 103 g/mol. The present result indicates that the activity of the beta-oxidation pathway under the aerobic–anaerobic condition
is reduced due to a reduction in the amount of dissolved oxygen. These findings have potential for use in controlling the
biosynthesis of long main-chain PHA by regulating the activity of the beta-oxidation pathway, which also could be regulated
by varying the dissolved oxygen concentration. 相似文献
998.
999.
Triticale is a frequently cultivated and used in feed rations because of high yields of kernels and straw. Furthermore triticale is cosidered in a culturelandscape program. The storage of triticale and storage conditions become more and more important. In our study Triticale was remoistered to a watercontent of 14, 16, 18, und 19% as well, inoculated withP verrucosum and stored for 28 weeks from november till july in a research granary (tower silo). This experiment should simulate the storage situation in farmscale from cold wintermonths to warm spring times. Every four weeks CO2 was measured, and samples for moisture, OTA- and CT-analysis were taken. At week 20 and a MC of 19 % 22 μg OTA/kg triticale were found. The maximum of OTA-production in this humidity stage was at week 28 with 635 μg/kg. Also at a MC of 18 % OTA could be found with levels near to the detection limit. In contrast to former investigations with oatsP verrucosum produced in triticale no citrinin even when the OTA concentrations were higher than in our investigations. 相似文献
1000.
We examined the relationship between body size of the riparian spider Nephila clavata and the contribution of allochthonous (aquatic insects) and autochthonous (terrestrial insects) sources to its diet using
stable isotope analysis. During the study period from July to September, the body size of the females increased remarkably
(about 60-fold) but that of males remained small. The biomass of both aquatic and terrestrial insects trapped on the spider
webs increased with spider size, with the biomass of the former ranging between 30 and 70% of that of the terrestrial insects.
The average relative contribution of aquatic insects to the diet of the spiders, calculated from δ13C values, was 40–50% in spiders in the early juvenile and juvenile stages, 35% in adult males and 4% in adult females. There
was a significant negative relationship between the relative contribution of aquatic insects and body size of the female spiders.
We conclude that aquatic insects might be an important seasonal dietary subsidy for small spiders and that these allochthonous
subsidies may facilitate the growth of riparian spiders, which may in turn enable the spiders to feed on larger prey. 相似文献