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1.
  1. The Euphrates softshell turtle (Rafetus euphraticus) is the most threatened chelonian species in the Middle East, where it is endemic to the Tigris and Euphrates basins. Since the ecology of this species is little known, it is difficult to plan any reliable action for its correct management and conservation.
  2. To enhance the scientific knowledge on R. euphraticus, and to establish a science-based management strategy, a detailed investigation was undertaken on the distribution, habitat, activity and home range of R. euphraticus in Turkey. The previous distribution records in Turkey are for the 1990s; thus, this study is the first comprehensive field research on the species after nearly 3 decades.
  3. There was a significant sexual size dimorphism in the Turkish population, with males larger than females.
  4. Four individuals were radiotracked for 1 year. The mean home range was highly variable depending on how it was calculated, but that of males was considerably greater than that of females by all methods used.
  5. A quantitative evaluation was made of habitat change with time. The land cover classes potentially available to turtles in the Euphrates River basin increased by more than 100% between the 1990s and 2018: 92% of this enhancement was derived from water bodies and coastal lands.
  6. Fifteen dams have been built in the lower part of the basins in the last 30 years. In addition, continuing human interactions have caused the fragmentation or destruction of suitable habitats for R. euphraticus.
  7. The factors threatening R. euphraticus were assessed and a conservation action plan was developed. Some objectives such as monitoring and creating awareness of this action plan have been met while others are still waiting to be achieved.
  相似文献   
2.
A high crop yield with the minimum possible cost to the environment is generally desirable. However, the complicated relationships among crop production, nitrogen (N) use efficiency and environmental impacts must be clearly assessed. We conducted a series of on-farm N application rate experiments to establish the linkage between crop yield and N2O emissions in the Guanzhong Plain in Northwest China. We also examined crop yield, partial factor productivity of applied N (PFPN) and reactive N (Nr) losses through a survey of 1 529 and 1 497 smallholder farms that grow wheat and maize, respectively, in the region. The optimum N rates were 175 and 214 kg ha–1 for winter wheat and summer maize, respectively, thereby achieving the yields of 6 799 and 7 518 kg ha–1, correspondingly, with low N2O emissions based on on-farm N rate experiments. Among the smallholder farms, the average N application rates were 215 and 294 kg ha–1 season–1, thus producing 6 490 and 6 220 kg ha–1 of wheat and maize, respectively. The corresponding PFPN values for the two crops were 36.8 and 21.2 kg N kg–1, and the total N2O emissions were 1.50 and 3.88 kg ha–1, respectively. High N balance, large Nr losses and elevated N2O emissions could be explained by the overdoses of N application and low grain yields under the current farming practice. The crop yields, N application rates, PFPN and total N2O for wheat and maize were 18 and 24% higher, 42 and 37% less, 75 and 116% higher, and 42 and 47% less, correspondingly, in the high-yield and high-PFPN group than in the average smallholder farms. In conclusion, closing the PFPN gap between the current average and the value for the high-yield and high-PFPN group would increase crop production and reduce Nr losses or the total N2O emissions for the investigated cropping system in Northwest China.  相似文献   
3.
Plant height is one of the most important agronomic traits associated with yield in maize.In this study,a gibberellins(GA)-insensitive dwarf mutant,m34,was screened from inbred line Ye478 by treatment with the chemical mutagen ethylmethanesulfonate(EMS).Compared to Ye478,m34 showed a dwarf phenotype with shorter internodes,and smaller leaf length and width,but with similar leaf number.Furthermore,m34 exhibited smaller guard cells in internodes than Ye478,suggesting that smaller cells might contribute to its dwarf phenotype.Genetic analysis indicated that the m34 dwarf phenotype was controlled by a recessive nuclear gene.An F2 population derived from a cross between m34 and B73 was used for mutational gene cloning and this gene was mapped to a chromosome region between umc2189 and umc1553 in chromosome 1 bin1.10,which harbored a previously identified dwarf gene Zm VP8.Sequencing analysis showed a nucleotide substitution(G1606 to A1606)in the sixth exon of ZmVP8,which resulted in an amino acid change(E531 to K531)from Ye478 to m34.This amino acid change resulted in anα-helix changing to aβ-sheet in the secondary protein structure and the‘SPEC’domain changed to a‘BOT1NT’domain in the tertiary protein structure.Taken together,these results suggested that m34 is a novel allelic mutant originally derived from Ye478 that is useful for further ZmVP8 functional analysis in maize.  相似文献   
4.
In the present study, a total of 150 samples including 50 salted anchovy, 50 raw anchovy, and 50 raw mussel samples collected from the retailers and small-scale producers in Samsun province from the Black Sea region of Turkey were analyzed; and 12% (6/50), 2% (1/50), and 2% (1/50) of the samples, respectively, were found to be contaminated with L. monocytogenes. According to the serotype distribution, six salted anchovy and one of the raw fish samples were contaminated with L. monocytogenes 1/2b (or 3b). In one raw mussel, both L. monocytogenes 1/2b (or 3b) and 4b (or 4d or 4e) serotypes were detected.  相似文献   
5.
Stu2p/XMAP215/Dis1 family proteins are evolutionarily conserved regulatory factors that use αβ-tubulin-interacting tumor overexpressed gene (TOG) domains to catalyze fast microtubule growth. Catalysis requires that these polymerases discriminate between unpolymerized and polymerized forms of αβ-tubulin, but the mechanism by which they do so has remained unclear. Here, we report the structure of the TOG1 domain from Stu2p bound to yeast αβ-tubulin. TOG1 binds αβ-tubulin in a way that excludes equivalent binding of a second TOG domain. Furthermore, TOG1 preferentially binds a curved conformation of αβ-tubulin that cannot be incorporated into microtubules, contacting α- and β-tubulin surfaces that do not participate in microtubule assembly. Conformation-selective interactions with αβ-tubulin explain how TOG-containing polymerases discriminate between unpolymerized and polymerized forms of αβ-tubulin and how they selectively recognize the growing end of the microtubule.  相似文献   
6.
Plant Foods for Human Nutrition - Diabetic kidney disease is one of the most common microvascular complications of diabetes mellitus with consequences of diabetic nephropathy. Here we amined to...  相似文献   
7.
To address nitrogen (N)-related environmental pollution, development of an economical, slow-release urea fertilizer is the need of the hour. A study was conducted on the reduction of nitrogen released from granular urea fertilizer by applying sulfur, gypsum, bentonite, and starch as coating material. Paraffin wax was used as a binder. The dissolution rates were studied by changing the composition of coating mixture using high-performance liquid chromatography. SEM was used to study the morphology of coated urea in terms of smoothness and uniformity. The ultraviolet spectroscopy analysis further authenticated the release behavior of coated urea in terms of nitrogen concentration. Coating material reduced the release rate of nitrogen from urea fertilizer, significantly. Mixture of sulfur and gypsum coating on urea gave slowest release rate of nitrogen from urea fertilizer, i.e., 37%, as compared to uncoated urea and thus seems to be the most promising binding material for product development.  相似文献   
8.
Eimeria (E.) tenella (local isolate) sporozoites were adapted on the chorioallantoic membrane (CAM) of 10-12 days chicken embryos and completed its life cycle in 6~7 days at 39℃ and 70 per cent humidity. Only 23 embryos (4.6%) were found dead from 1~4 day post inoculation of sporozoites with mild lesions on CAM with no gametocytes but few sporozoites in chorioallantoic fluid (CAF). On 5~7 day post inoculation, 432 embryos (86.4%) were found dead with severe haemorrhages on CAM and CAF contained uncountable number of gametocytes. After seven days post inoculation, 45 embryos (9%) were found to be alive. Some oocysts were also detected in the CAF on 6~7 days post inoculation. In the histological sections of the CAM, there were abundant small dark colored rounded bodies of gametes; distributed extensively in tissues of CAM on 5~7 days post inoculation of sporozoites. In some cases, cluster of small mature and immature relatively large bodies were seen in increasing numbers on 5~6 days post inoculation.  相似文献   
9.
Electropolymerization of carbazole (Cz) by cyclic voltammetry (CV) onto carbon fiber microelectrodes (CFME) (diameter ∼7 μm) in dichloromethane (CH2Cl2) solution of 0.1 mol·dm−3 tetraethyl ammonium perchlorate (TEAP) results in the formation of polycarbazole (PCz) thin film coatings. CV results showed that these PCz thin films have reversible redox behavior in monomer-free electrolyte solution. The resulting thin polymer films were characterized using Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR) and atomic force microscopy (AFM). Results performed at optimum experimental conditions indicate that electrodes show a reversible and stable behavior over sixty eight days of testing for dopamine in 100 μmol·dm−3 buffer solution. A detection limit for PCz thin films as low as 0.1 μM (3S/N) was obtained for the polycarbazole (PCz) thin films formed using CV. Hence, this novel sensor can be considered as promising sensor for dopamine detection.  相似文献   
10.
Gram-negative marine bacteria can thrive in harsh oceanic conditions, partly because of the structural diversity of the cell wall and its components, particularly lipopolysaccharide (LPS). LPS is composed of three main parts, an O-antigen, lipid A, and a core region, all of which display immense structural variations among different bacterial species. These components not only provide cell integrity but also elicit an immune response in the host, which ranges from other marine organisms to humans. Toll-like receptor 4 and its homologs are the dedicated receptors that detect LPS and trigger the immune system to respond, often causing a wide variety of inflammatory diseases and even death. This review describes the structural organization of selected LPSes and their association with economically important diseases in marine organisms. In addition, the potential therapeutic use of LPS as an immune adjuvant in different diseases is highlighted.  相似文献   
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