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61.
Identifying critical migratory bottlenecks and high‐use areas for an endangered migratory soaring bird across three continents 下载免费PDF全文
Evan R. Buechley Steffen Oppel William S. Beatty Stoyan C. Nikolov Vladimir Dobrev Volen Arkumarev Victoria Saravia Clementine Bougain Anastasios Bounas Elzbieta Kret Theodora Skartsi Lale Aktay Karen Aghababyan Ethan Frehner Çağan H. Şekercioğlu 《Journal of avian biology》2018,49(7)
Migrant birds face a number of threats throughout their annual cycle, including persecution, collision with energy infrastructure, and habitat and climate change. A key challenge for the conservation of migrants is the identification of important habitat, including migratory concentration areas, because species survival rates may be determined by events in geographically very limited areas. Remote‐tracking technology is facilitating the identification of such critical habitat, although the strategic identification of important sites and incorporation of such knowledge in conservation planning remains limited. We tracked 45 individuals of an endangered, soaring migrant (Egyptian vulture Neophron percnopterus), over 75 complete migrations that traversed three continents along the Red Sea Flyway. We summarize and contextualize migration statistics by season and age class, including migration start, midpoint, and end dates, as well as linear and cumulative migration distance, migration duration and speed, and route straightness. Then, using dynamic Brownian bridge movement models, we quantified space use to identify the most important migratory bottlenecks and high‐use areas on the flyway. These areas each accounted for < 5% of the overall movement range of the tracked birds, yet > 20% of all tracks passed through bottlenecks, and > 50% of the overall vulture time spent on migration fell within high‐use areas. The most important sites were located at the southeastern Red Sea coast and Bab‐el‐Mandeb Strait (Saudi Arabia, Yemen, Djibouti), the Suez Canal zone (Egypt), and the Gulf of Iskenderun (Turkey). Discouragingly however, none of the area within the major migratory bottlenecks was protected and < 13% of the high‐use areas were protected. This demonstrates a very concerning gap in the protected area network for migratory soaring birds along the Red Sea Flyway. Because reducing threats at migratory concentrations can be a very efficient approach to protect populations, our work provides clear guidelines where conservation investment is urgently needed to benefit as many as 35 migratory soaring‐bird species that regularly use the Red Sea Flyway. 相似文献
62.
An integrative anatomical,morphological, micromorphological and molecular approach to Turkish epidendroid and orchidoid species (Orchidaceae) 下载免费PDF全文
Gülcan Şenel Şenay Süngü Şeker Mustafa Kemal Akbulut Öznur Ergen Akçin 《Nordic Journal of Botany》2018,36(7)
We aimed to describe and analyse the morphological, anatomical and micromorphological traits of 36 Turkish orchids representing 12 genera (e.g. Anacamptis, Cephalanthera, Dactylorhiza, Orchis, Serapias) in detail and analyse their usability for solving phylogenetic and taxonomic issues. We applied UPGMA cluster analysis to anatomical, morphological and micromorphological characters such as root tubers, leaf and flower structures, pit, sclerenchymatic sheath, vascular bundle shape, crystal and starch, exodermis and endodermis structure, stomata type, bulliform cells in roots, shoots and leaves, surface structures like papillae, hairs and ornamentation on flower parts, leaves, fruits and seeds. Furthermore, in a phylogenetic framework, we analysed nuclear ribosomal ITS diversity in the same orchid species belonging, and in a combined Bayesian phylogenetic analysis based on anatomical, morphological, micromorphogical and ITS data we confirmed the usefulness of multiple data sets for effectively assessing taxonomically critical orchids. In the combined analysis, all genera were resolved as monophyletic with topologies congruent with recently published more thorough molecular phylogenetic reconstructions, while the trees obtained by seprately analysing the ITS and the anatomical, morphological, micromorphogical data were less resolved and partly inconclusive. 相似文献
63.
Mallomonas is the largest genus of the Synurophyceae (chrysophytes) and includes more than 120 species. Most of them are cosmopolitan,
living in freshwater habitats. The Rumanian taxa occur usually in spring or early summer at water temperatures ranging between
4 ° and 10 °C. They are most frequent in neutral or slightly acid, clear-watered, aquatic habitats of various types. However,
Mallomonas paludosa Fott appears mostly in brown watered peatbog pools of low mineral contents, having a particular geographical area, with its
southernmost limit in the Rumanian Eastern Carpathians. Its distribution, like that of other boreal elements, is strictly
connected with the occurrence of genuine ombrogenic Sphagnum-bogs, which have their southern limit also in Romania. The other two species dealt with — M. cyathellata Wujek & Asmund and M. portae-ferreae Péterfi & Asmund —, occurring in circumneutral or moderately alkaline waters of eutrophic character, are apparently warm
water forms, mostly distributed in tropical, subtropical or mediterranean zones. The Rumanian localities (in the Danube Delta
and at Eşelniţa near the Danube, up stream Drobeta Turnu-Severin) might be the northern limits of M. portae-ferreae in Eastern Europe. The Danube Delta is the only locality of M. cyathellata in Europe, and its northernmost occurrence as well. The occurrence of both species in Rumania is presumably due to migratory
waterfowl. 相似文献
64.
Türkan Patiroğlu Gürses Şahin Olgun Kontaş Kazim Üzüm Recep Saraymen 《Biological trace element research》1997,56(2):179-185
In this study, we wanted to examine the effect of magnesium (Mg2+) supplementation on the experimental 3-methyl cholantrene (3-MC)-induced fibrosarcoma and alterations in (Mg2+) distribution in several tissues of the rats, during carcinogenesis. It was determined that serum and tissue (Mg2+) levels of the rats in (Mg2+)-supplemented diet group were higher than those of the rats in the (Mg2+)-nonsupplemented and control groups. The mean time of fibrosarcoma development for (Mg2+)-supplemented group was longer than (Mg2+)-nonsupplemented group (p<0.05). Symptoms of hypermagnesemia were not observed in any of the rats. These results suggests that dietary (Mg2+) supplementation may have a partial anticarcinogenic effect on experimental 3-MC-induced fibrosarcoma by prolongation of the latent period of carcinogenesis. 相似文献
65.
Aydin Ece Bekir Sami Uyamik Akin IŞcan Pelin Ertan M. Ramazan Yiğitolu 《Biological trace element research》1997,59(1-3):31-39
In order to evaluate serum copper and zinc status in children with iron deficiency anemia (IDA), 60 children with IDA aged
1–14 yr and 64 healthy children as controls aged 1–14 yr were included the study. Serum copper levels were higher in children
with IDA (189 ± 49 (Μg/dL) than those of controls (163 ± 37 Μg/dL) (p = 0.001). Serum zinc levels were lower in the patient group (109 ± 59 Μg/dL) than those of control subjects (135 ± 56 Μg/dL)
(p = 0.017). In addition, there were statistically significant negative correlations between hematological parameters and serum
copper levels in the patient group, but not in controls. No correlation between hematological parameters and serum zinc levels
were found in both patient and control groups, except positive correlation between mean corpuscular volume (MCV) and serum
zinc level in patients.
It was concluded that at the time of managing children with IDA, zinc deficiency must be borne in mind and if necessary treatment
should be initiated with zinc. 相似文献
66.
Yunus Ugan Mustafa Nazıroğlu Mehmet Şahin Mehmet Aykur 《The Journal of membrane biology》2016,249(4):437-447
67.
Koray Oktay Leyla Polat Köse Kıvılcım Şendil Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):939-945
The synthesis of (Z)-4-oxo-4-(arylamino)but-2-enoic acid (4) derivatives containing structural characteristics that can be used for the synthesis of several active molecules, is presented. Some of the butenoic acid derivatives (4a, 4c, 4e, 4i, 4j, 4k) are synthesized following literature procedures and at the end of the reaction. In addition, structures of all synthesized derivatives (4a–4m) were determined by 1H-NMR, 13C-NMR and IR spectroscopy. Carbonic anhydrase is a metalloenzyme involved in many crucial physiologic processes as it catalyzes a simple but fundamental reaction, the reversible hydration of carbon dioxide to bicarbonate and protons. Significant results were obtained by evaluating the enzyme inhibitory activities of these derivatives against human carbonic anhydrase hCA I and II isoenzymes (hCA I and II). Butenoic acid derivatives (4a–4m) strongly inhibited hCA I and II with Kis in the low nanomolar range of 1.85?±?0.58 to 5.04?±?1.46?nM against hCA I and in the range of 2.01?±?0.52 to 2.94?±?1.31?nM against hCA II. 相似文献
68.
69.
The aim of this study was to increase the stability and water solubility of fragrance materials, to provide controlled release of these compounds, and to convert these substances from liquid to powder form by preparing their inclusion complexes with cyclodextrins (CDs). For this purpose, linalool and benzyl acetate were chosen as the fragrance materials. The use of beta-cyclodextrin (beta CD) and 2-hydroxypropyl-beta-cyclodextrin (2-HP beta CD) for increasing the solubility of these 2 fragrance materials was studied. Linalool and benzyl acetate gave a B-type diagram with beta CD, whereas they gave an A(L)-type diagram with 2-HP beta CD. Therefore, complexes of fragrance materials with 2-HP beta CD at 1:1 and 1:2 molar ratios (guest:host) were prepared. The formation of inclusion complexes was confirmed using proton nuclear magnetic resonance ((1)H-NMR) spectroscopy and circular dichroism spectroscopy. The results of the solubility studies showed that preparing the inclusion complex with 2-HP beta CD at a 1:1 molar ratio increased the solubility of linalool 5.9-fold and that of benzyl acetate 4.2-fold, whereas the complexes at a 1:2 molar ratio increased the solubility 6.4- and 4.5-fold for linalool and benzyl acetate, respectively. The stability and in vitro release studies were performed on the gel formulations prepared using uncomplexed fragrance materials or inclusion complexes of fragrance materials at a 1:1 molar ratio. It was observed that the volatility of both fragrance materials was decreased by preparing the inclusion complexes with 2-HP beta CD. Also, in vitro release data indicated that controlled release of fragrances could be possible if inclusion complexes were prepared. 相似文献
70.
Okudan N Nurullahoğlu-Atalık KE Revan S Belviranlı M Balcı ŞS Gökbel H Pepe H 《Acta physiologica Hungarica》2012,99(1):40-50
In this study, the effect of long-term supplementation of coenzyme Q10 (CoQ10) on the responses of swim-trained rat aorta was investigated. Twenty-four adult male Wistar rats were divided into four groups: untrained, trained, untrained+CoQ10, and trained+CoQ10 group. In the trained groups rats swam for 60 min/day, five days/week for six weeks. The CoQ10 supplements were administered by intraperitoneal injection at a daily dose of 10 mg·kg-1 of body weight five days/week for six weeks. Swimming of the rats was performed in a container containing tap water. Rats were sacrificed and thoracic aortas were removed for ex vivo analysis after the last swimming session. The aortas were cut into rings 2.5 mm in length. Concentration-response curves for phenylephrine (PHE, 10-9-3×10-4 M) and potassium chloride (KCl, 5-100 mM) were isometrically recorded. The sensitivity and maximal responses to PHE and KCl of aortic rings obtained from trained rats were lower than those of untrained rats. CoQ10 supplementation decreased the responses to both vasoconstrictors in untrained and especially in trained groups. Although neither CoQ10 nor training did affect malondialdehyde (MDA) and protein carbonyl (PC) levels, creatine kinase (CK) activity decreased and superoxide dismutase (SOD) activity increased only with exercise training. Glutathione (GSH) levels increased in CoQ10 supplemented-untrained rats. In conclusion, our results suggest that CoQ10 supplementation may have beneficial effects during exercise. 相似文献