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Külköylüoğlu O Sari N Akdemir D Yavuzatmaca M Altinbağ C 《High altitude medicine & biology》2012,13(2):126-137
We evaluated Rapoport's rule which states a negative correlation between species richness and altitude. To understand the relationship between altitude and reproductive modes (a/sexual) of non-marine ostracods, 166 aquatic bodies in Ordu region, Turkey were randomly sampled from July 11 to July 16, 2010. A total of 26 species of ostracods were found from 133 out of 166 sites. Except for one species (Heterocypris incongruens), the other 25 species were new reports for the region. Candona improvisa was also a new report for Turkish ostracod fauna. Three species (Psychrodromus olivaceus, H. incongruens, and C. neglecta) occurred most frequently as 43, 46, and 76 times, respectively. Canonical correspondence analyses exhibited two variables [Habitat type (p=0.014; F=2.171) and water temperature (p=0.018; F=2.248)] as having the most effect on species. Correlation of species' reproductive modes to those of environmental variables measured was not significant. UPGMA dendrogram displayed 15 most frequently occurring species into four clusters where most species (11) were asexual. Although a small group (asexual species without swimming setae) showed a tendency to habitat type and electrical conductivity, such variables are believed to play secondary role on species distribution. Highest species diversity (13 species) was observed at the range of 1200 and 1400?m (a.s.l.), where numbers of stations sampled was not the highest (22). Numbers of asexual species (19) were higher than the sexual (11) but there were no significant differences (p>0.05) between the frequencies of their occurrences at different altitudinal ranges. Accordingly, our findings do not support the Rapoport Rule. Results yield that reproductive modes of species (sexual and asexual) was not directly correlated to altitude or any environmental variables measured during this study. A better explanation of ostracod diversity appears to be suitability of habitats. 相似文献
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Fatiha Bouihi Bruno Schmaltz Fabrice Mathevet David Kreher Jrme Faure-Vincent Ceren Yildirim Ahmed Elhakmaoui Johann Boucl Mohamed Akssira Franois Tran-Van Mohamed Abarbri 《Materials》2022,15(22)
Donor–acceptor (D–A) small molecules are regarded as promising hole-transporting materials for perovskite solar cells (PSCs) due to their tunable optoelectronic properties. This paper reports the design, synthesis and characterization of three novel isomeric D-π-A small molecules PY1, PY2 and PY3. The chemical structures of the molecules consist of a pyrazolo[1,5-a]pyrimidine acceptor core functionalized with one 3,6-bis(4,4′-dimethoxydiphenylamino)carbazole (3,6-CzDMPA) donor moiety via a phenyl π-spacer at the 3, 5 and 7 positions, respectively. The isolated compounds possess suitable energy levels, sufficient thermal stability (Td > 400 °C), molecular glass behavior with Tg values in the range of 127–136 °C slightly higher than that of the reference material Spiro-OMeTAD (126 °C) and acceptable hydrophobicity. Undoped PY1 demonstrates the highest hole mobility (3 × 10−6 cm2 V−1 s−1) compared to PY2 and PY3 (1.3 × 10−6 cm2 V−1 s−1). The whole isomers were incorporated as doped HTMs in planar n-i-p PSCs based on double cation perovskite FA0.85Cs0.15Pb(I0.85Br0.15)3. The non-optimized device fabricated using PY1 exhibited a power conversion efficiency (PCE) of 12.41%, similar to that obtained using the reference, Spiro-OMeTAD, which demonstrated a maximum PCE of 12.58% under the same conditions. The PY2 and PY3 materials demonstrated slightly lower performance in device configuration, with relatively moderate PCEs of 10.21% and 10.82%, respectively, and slight hysteresis behavior (−0.01 and 0.02). The preliminary stability testing of PSCs is also described. The PY1-based device exhibited better stability than the device using Spiro-OMeTAD, which could be related to its slightly superior hydrophobic character preventing water diffusion into the perovskite layer. 相似文献
35.
Aysu Ceren Okur Philipp Erni Lahoussine Ouali Daniel Benczedi Esther Amstad 《RSC advances》2023,13(12):7731
Many properties of materials, including their dissolution kinetics, hardness, and optical appearance, depend on their structure. Unfortunately, it is often difficult to control the structure of low molecular weight organic compounds that have a high propensity to crystallize if they are formulated from solutions wherein they have a high mobility. This limitation can be overcome by formulating these compounds within small airborne drops that rapidly dry, thereby limiting the time molecules have to arrange into the thermodynamically most stable phase. Such drops can be formed with a surface acoustic wave (SAW)-based spray-drier. In this paper, we demonstrate that the structure of a model low molecular weight compound relevant to applications in pharmacology and food, succinic acid, can be readily controlled with the supersaturation rate. Succinic acid particles preserve the metastable structure over at least 3 months if the initial succinic acid concentration is below 2% of its saturation concentration such that the supersaturation rate is high. We demonstrate that also the stability of the metastable phases against their transformation into the most stable phase increases with decreasing initial solute concentration and hence with increasing supersaturation rate of the spray-dried solution. These insights open up new opportunities to control the crystal structure and therefore properties of low molecular weight compounds that have a high propensity to crystallize.A surface acoustic wave based microfluidic spray-drier is used to spray dry succinic acid, a model low molecular weight matrix substance. We demonstrate that the structure of succinic acid can be tuned with its formation time within drying drops. 相似文献
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High serum transforming growth factor beta 1 (TGFB1) level predicts better survival in breast cancer
Rumeysa Ciftci Faruk Tas Ceren Tilgen Yasasever Ece Aksit Senem Karabulut Fatma Sen Serkan Keskin Leyla Kilic İbrahim Yildiz Hamza Ugur Bozbey Derya Duranyildiz Sezai Vatansever 《Tumour biology》2014,35(7):6941-6948
The transforming growth factor beta 1 (TGFB1) is a regulatory cytokine with both tumor suppressor and tumor-promoting effects in breast cancer (BC) cell lines and tissue. Data about level of circulating TGFB1 and its prognostic significance in BC patients is conflicting. The objective of this study is to determine the clinical significance of the serum TGFB1 levels in BC patients. We enrolled 96 female patients with histopathologically diagnosed BC who did not receive chemotherapy (CT) or radiotherapy. Serum TGFB1 levels were measured by ELISA method and compared with 30 healthy controls. The mean serum TGFB1 level of BC patients was significantly higher than controls (0.08 vs. 0.04 ng/ml, p?<?0.001). There was no significant difference according to known disease-related clinicopathological or laboratory parameters. Serum TGFB1 level had a significant impact on overall survival in both univariate (p?=?0.01) and multivariate analysis (p?=?0.013). Serum TGFB1 level is elevated in BC patients and has a favorable prognostic value. However, it has no predictive role on CT response. 相似文献
39.
N. Yordam A. Özön A. Alikaşifoğlu A. Özgen N. Ceren Y. Zafer E. Şimşek 《European journal of pediatrics》1999,158(6):501-505
Turkey is an iodine deficiency area. The overall goitre prevalence is thought to be 30%, and most epidemiological studies
give figures compatible with mild to moderate iodine deficiency. However, it is suspected that there are regions where iodine
deficiency might be more severe than previously known. In this study the goitre prevalence and iodine status in a mountain
village in Central Anatolia were investigated and the results compared to those of an urban area with mild iodine deficiency.
Parameters of iodine status in the mountainous region showed severe iodine deficiency comparable to that in Central Africa.
It seems that there are regions in Turkey where current programmes of salt iodization will be inadequate to correct the problem
of iodine deficiency.
Conclusions Our observations suggest that regional variations in iodine status may impede the success of salt iodization programmes,
which alone may not be adequate for correction of the problem country-wide. Alternative sources of iodine should be considered
in addition to expanded and more efficient salt iodization programmes.
Received: 17 August 1998 / Accepted: 30 November 1998 相似文献
40.
Shyam K. Pahari Tugba Ceren Gokoglan Benjoe Rey B. Visayas Jennifer Woehl James A. Golen Rachael Howland Maricris L. Mayes Ertan Agar Patrick J. Cappillino 《RSC advances》2021,11(10):5432
The cost of electricity generated by wind and solar installations has become competitive with that generated by burning fossil fuels. While this paves the way for a carbon-neutral electrical grid, short- and long-term intermittency necessitates energy storage. Flow batteries are a promising technology to accommodate this need, with numerous advantages, including decoupled power and energy ratings, which imparts flexibility, thermal stability, and safety. Further, development of robust nonaqueous systems has the potential to greatly improve energy density, approaching that of lithium-ion batteries, while maintaining the advantages of flow systems. Herein we report a breakthrough on a bio-inspired nonaqueous redox flow battery (NRFB) electrolyte, which contains high-concentration active-material and maintains stability during deep cycling for extended time-periods. These advances are reinforced by thermodynamic considerations and computational investigations, which provide a clear path to further improvements. Electrochemical studies confirm that the active-material maintains its high stability at high concentration. This molecular scaffold clears two important hurdles in designing active-materials for nonaqueous electrolytes – low solubility and poor stability – providing an in-road to development of high-performance NRFB systems.With the cost of renewable energy near parity with fossil fuels, energy storage is paramount. We report a breakthrough on a bioinspired NRFB active-material, with greatly improved solubility, and place it in a predictive theoretical framework. 相似文献