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61.
Polat Derya Genc Durmaz Yasar Konar Nevzat Pirouzian Haniyeh Rasouli Toker Omer Said Palabiyik Ibrahim Tasan Murat 《Journal of applied phycology》2022,34(1):375-383
Journal of Applied Phycology - In this study, dried or encapsulated Nannochloropsis oculata microalgal biomass was used in spread samples (0.00–0.75 g (100 g)?1... 相似文献
62.
Mohamad I. Nugraha Hyunho Kim Bin Sun Saheena Desai F. Pelayo Garcia de Arquer Edward H. Sargent Husam N. Alshareef Derya Baran 《Liver Transplantation》2019,9(28)
Colloidal quantum dots (CQDs) are attractive materials for thermoelectric applications due to their simple and low‐cost processing; advantageously, they also offer low thermal conductivity and high Seebeck coefficient. To date, the majority of CQD thermoelectric films reported upon have been p‐type, while only a few reports are available on n‐type films. High‐performing n‐ and p‐type films are essential for thermoelectric generators (TEGs) with large output voltage and power. Here, high‐thermoelectric‐performance n‐type CQD films are reported and showcased in high‐performance all‐CQD TEGs. By engineering the electronic coupling in the films, a thorough removal of insulating ligands is achieved and this is combined with excellent surface trap passivation. This enables a high thermoelectric power factor of 24 µW m?1 K?2, superior to previously reported n‐type lead chalcogenide CQD films operating near room temperature (<1 µW m?1 K?2). As a result, an all‐CQD film TEG with a large output voltage of 0.25 V and a power density of 0.63 W m?2 at ?T = 50 K is demonstrated, which represents an over fourfold enhancement to previously reported p‐type only CQD TEGs. 相似文献
63.
Mohamad I. Nugraha Hyunho Kim Bin Sun Md Azimul Haque Francisco Pelayo Garcia de Arquer Diego Rosas Villalva Abdulrahman El‐Labban Edward H. Sargent Husam N. Alshareef Derya Baran 《Liver Transplantation》2019,9(13)
Colloidal quantum dots (CQDs) are demonstrated to be promising materials to realize high‐performance thermoelectrics owing to their low thermal conductivity. The most studied CQD films, however, are using long ligands that require high processing and operation temperature (>400 °C) to achieve optimum thermoelectric performance. Here the thermoelectric properties of CQD films cross‐linked using short ligands that allow strong inter‐QD coupling are reported. Using the ligands, p‐type thermoelectric solids are demonstrated with a high Seebeck coefficient and power factor of 400 μV K?1 and 30 µW m?1 K?2, respectively, leading to maximum ZT of 0.02 at a lower measurement temperature (<400 K) and lower processing temperature (<300 °C). These ligands further reduce the annealing temperature to 175 °C, significantly increasing the Seebeck coefficient of the CQD films to 580 μV K?1. This high Seebeck coefficient with a superior ZT near room temperature compared to previously reported high temperature‐annealed CQD films is ascribed to the smaller grain size, which enables the retainment of quantum confinement and significantly increases the hole effective mass in the films. This study provides a pathway to approach quantum confinement for achieving a high Seebeck coefficient yet strong inter‐QD coupling, which offers a step toward low‐temperature‐processed high‐performance thermoelectric generators. 相似文献
64.
The regulatory effect of melatonin on physiological,biochemical and molecular parameters in cold-stressed wheat seedlings 总被引:1,自引:0,他引:1
Hulya Turk Serkan Erdal Mucip Genisel Okkes Atici Yavuz Demir Derya Yanmis 《Plant Growth Regulation》2014,74(2):139-152
We investigated the possible mediatory role of melatonin in protecting wheat plants from cold stress. Ten-day-old wheat seedlings were pretreated with 1 mmol l?1 melatonin for 12 h and subsequently exposed to stress conditions at 5/2 °C (day/night) for 3 days. Cold stress caused serious reductions in leaf surface area, water content, and photosynthetic pigment content, whereas melatonin application attenuated these reductions. Accumulation of reactive oxygen species (ROS), including superoxide and hydrogen peroxide, was very high in cold-stressed plants and caused lipid peroxidation in membranes. Concomitantly, ROS damaged the DNA profile and negatively influenced expression and/or activity of many enzymes, including RuBisCo. When compared to controls, cold-stressed plants had higher activities of the antioxidant enzymes superoxide dismutase, guaicol peroxidase, ascorbate peroxidase, and glutathione reductase and higher levels of the antioxidant compounds total ascorbate, reduced ascorbate, total glutathione, reduced glutathione, and phenolic substances; however, this elevation could not cope with the destructive effects of cold stress. Melatonin-pretreated plants exhibited greater increases in these parameters comparison with untreated cold-stressed plants. Isozyme bands monitored in native gel and RuBisCo expression supported these changes. Also, due to the cold-induced increase in dehydroascorbate and oxidized glutathione, the corrupted redox status in the cell was ameliorated by melatonin application. Similarly, levels of the osmoprotectants total soluble protein, carbohydrate, and proline were also increased by cold stress; however, melatonin-applied seedlings had a higher content of these solutes in comparison to untreated cold-stressed plants. We suggest that melatonin can improve plant resistance to cold stress in wheat seedlings by directly scavenging ROS and by modulating redox balance and other defence mechanisms. 相似文献
65.
Hakan Erdem Zeliha Kocak-Tufan Omer Yilmaz Zuhal Karakurt Aykut Cilli Hulya Turkan Ozlem Yazicioglu-Mocin Nalan Adıguzel Gokay Gungor Canturk Taşcı Gulden Yilmaz Oral Oncul Aygul Dogan-Celik Ozcan Erdemli Nefise Oztoprak Yakup Tomak Asuman Inan Demet Tok Sibel Temur Hafize Oksuz Ozgur Senturk Unase Buyukkocak Fatma Yilmaz-Karadag Derya Ozturk-Engin Dilek Ozcengiz Ahmet Karakas Hayati Bilgic Hakan Leblebicioglu 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-5
Background
Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.Findings
Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [3H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.Conclusions
These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis. 相似文献66.
Baris Gulcu Derya Ulug Canan Hazir Mehmet Karagoz 《Biocontrol Science and Technology》2014,24(8):965-970
In laboratory studies, we demonstrated that five native entomopathogenic nematode species/isolates caused 100% mortality of Spodoptera cilium larvae, a soil surface-feeding pest of turfgrass. At 25 infective juveniles/cm2 applied to sod, two selected Turkish species, Steinernema carpocapsae and Heterorhabditis bacteriophora (Sarigerme isolate), averaged 77% and 29% larval mortality, respectively. 相似文献
67.
Herzig MC Bidinosti M Schweizer T Hafner T Stemmelen C Weiss A Danner S Vidotto N Stauffer D Barske C Mayer F Schmid P Rovelli G van der Putten PH Shimshek DR 《PloS one》2012,7(5):e36581
The G2019S mutation in the multidomain protein leucine-rich repeat kinase 2 (LRRK2) is one of the most frequently identified genetic causes of Parkinson's disease (PD). Clinically, LRRK2(G2019S) carriers with PD and idiopathic PD patients have a very similar disease with brainstem and cortical Lewy pathology (α-synucleinopathy) as histopathological hallmarks. Some patients have Tau pathology. Enhanced kinase function of the LRRK2(G2019S) mutant protein is a prime suspect mechanism for carriers to develop PD but observations in LRRK2 knock-out, G2019S knock-in and kinase-dead mutant mice suggest that LRRK2 steady-state abundance of the protein also plays a determining role. One critical question concerning the molecular pathogenesis in LRRK2(G2019S) PD patients is whether α-synuclein (aSN) has a contributory role. To this end we generated mice with high expression of either wildtype or G2019S mutant LRRK2 in brainstem and cortical neurons. High levels of these LRRK2 variants left endogenous aSN and Tau levels unaltered and did not exacerbate or otherwise modify α-synucleinopathy in mice that co-expressed high levels of LRRK2 and aSN in brain neurons. On the contrary, in some lines high LRRK2 levels improved motor skills in the presence and absence of aSN-transgene-induced disease. Therefore, in many neurons high LRRK2 levels are well tolerated and not sufficient to drive or exacerbate neuronal α-synucleinopathy. 相似文献
68.
Mehmet Yavuzatmaca Derya Akdemir Necmettin Sari 《International Review of Hydrobiology》2012,97(4):247-261
To understand the relationship between local (alpha) diversity of ostracods and their distribution, 95 different locations were randomly sampled from southern Kahramanmaraş (Turkey) between 7 June and 31 July, 2010. Total of 46 ostracods were encountered from 68 sites. Four alpha diversity indices (Shannon‐Wiener, Menhinick, Brillouin, Margalef) individually quantified higher species diversity and evenness for three types of habitats (limnocrene springs, ponds, stream). Diversity partitioning analyses revealed a significant and substantial beta‐diversity among the sites. First axis of CCA exhibited about 71% of the correlations between species and environmental variables. Water temperature, having either a negative or positive correlation with individual species, was the most influential factor affecting diversity. Altitude did not significantly affect the numbers of species identified from the elevation ranges of 400–600 m and 800–1000 m. At least nine cosmopolitan species from 56 sites had an important contribution to local diversity. Hence, suitability of aquatic (ecological) conditions and habitat types provide better explanations for ostracod diversity than do other abiotic factors such as altitude, pH and salinity. The results may support the Habitat Diversity Hypothesis but the study needs to be expanded to different regions and cannot be generalized at the moment. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
69.
Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on physical properties and surface roughness of red-bud maple (Acer trautvetteri Medw.) wood were examined. Samples obtained from Düzce Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures and durations. The physical properties of heat-treated samples were compared against controls in order to determine their; oven-dry density, air-dry density, and swelling properties. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements, using the stylus method, were made in the direction perpendicular to the fiber. Three main roughness parameters; mean arithmetic deviation of profile (Ra), mean peak-to-valley height (Rz), and maximum roughness (Rmax) obtained from the surface of wood, were used to evaluate the effect of heat treatment on the surface characteristics of the specimens. Significant differences were determined (p>0.05) between surface roughness parameters (Ra, Rz, Rmax) at three different temperatures and three periods of heat treatment. The results showed that the values of density, swelling and surface roughness decreased with increasing temperature treatment and treatment times. Red-bud maple wood could be utilized successfully by applying proper heat treatment techniques without any losses in investigated parameters. This is vital in areas, such as window frames, where working stability and surface smoothness are important factors. 相似文献
70.