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101.
In this study, the relationships among problematic mobile phone use, age, gender, personality and chronotype of Turkish university students were examined. The study included 902 university students (73% female, 27% male) and their participation in the study was anonymous and voluntary. Data were collected from each participant by assessing a demographic questionnaire, Composite Scale of Morningness (CSM) as a measure of chronotype, the Big Five Inventory (BIG-5) for personality assessment and Mobile Phone Problem Usage Scale (MPPUS). The most important result was that CSM scores were the best predictor for problematic mobile phone usage, and as a consequence, evening-oriented university students scored higher on the MPPUS. This result remained, even when compared with the most influential personality predictor, conscientiousness. In addition, while extraversion positively predicted, emotional stable and chronotype negatively predicted problematic mobile phone use. Lastly, age and gender were not predictors of problematic mobile phone use. 相似文献
102.
103.
Frank W. Albert Mehmet Somel Miguel Carneiro Ayinuer Aximu-Petri Michel Halbwax Olaf Thalmann Jose A. Blanco-Aguiar Irina Z. Plyusnina Lyudmila Trut Rafael Villafuerte Nuno Ferrand Sylvia Kaiser Per Jensen Svante P??bo 《PLoS genetics》2012,8(9)
Domestication has led to similar changes in morphology and behavior in several animal species, raising the question whether similarities between different domestication events also exist at the molecular level. We used mRNA sequencing to analyze genome-wide gene expression patterns in brain frontal cortex in three pairs of domesticated and wild species (dogs and wolves, pigs and wild boars, and domesticated and wild rabbits). We compared the expression differences with those between domesticated guinea pigs and a distant wild relative (Cavia aperea) as well as between two lines of rats selected for tameness or aggression towards humans. There were few gene expression differences between domesticated and wild dogs, pigs, and rabbits (30–75 genes (less than 1%) of expressed genes were differentially expressed), while guinea pigs and C. aperea differed more strongly. Almost no overlap was found between the genes with differential expression in the different domestication events. In addition, joint analyses of all domesticated and wild samples provided only suggestive evidence for the existence of a small group of genes that changed their expression in a similar fashion in different domesticated species. The most extreme of these shared expression changes include up-regulation in domesticates of SOX6 and PROM1, two modulators of brain development. There was almost no overlap between gene expression in domesticated animals and the tame and aggressive rats. However, two of the genes with the strongest expression differences between the rats (DLL3 and DHDH) were located in a genomic region associated with tameness and aggression, suggesting a role in influencing tameness. In summary, the majority of brain gene expression changes in domesticated animals are specific to the given domestication event, suggesting that the causative variants of behavioral domestication traits may likewise be different. 相似文献
104.
Batch cultivations were performed to evaluate the influence of phosphate concentrations (0.25, 0.5, 0.75, and 1.0 g L−1) for pH regimes (9.5, 10.0, and 10.5) on the biomass production by Spirulina platensis. The best condition for cell growth (3.099 g L−1) was found at 0.5 g L−1 phosphate and pH value of 10.0. Cultivation time, phosphate, and pH caused to increase significantly (p < 0.01) in biomass production by S. platensis. Lag time was observed up to 4 h. After then, biomass production increased sharply (p < 0.01) from 0.020 g L−1 to 2.063, 2.213, 1.532, and 0.797 g L−1 at 0.25, 0.5, 0.75, and 1.0 g L−1 phosphate values, respectively. Modified Gompertz model could be regarded as sufficient to describe the biomass production by S. platensis with high determination coefficients and low sum of square value indicated that. Biological parameters for biomass production were successfully predicted by modified Gompertz model. 相似文献
105.
In the current study, fifteen halophilic and halotolerant bacteria were isolated from salt-affected soil of ?anl?urfa, Turkey. The isolates were characterized by conventional and molecular techniques (16S rDNA sequence analyses) as belonging to seven different genus including Bacillus (5 isolates), Halobacillus (1 isolate), Oceanobacillus (2 isolates), Halomonas (3 isolate), Nesterenkonia (1 isolate), Chromohalobacter (2 isolates) and Jeotgalibacillus (2 isolates). According to the results obtained, the investigated bacterial strains have high salt tolerance and significant enzyme activities which can improve soil nutrient cycling and fertility. Furthermore, these bacterial strains have been investigated for their ability to dissolve common salts available in salt-affected soils. Salt dissolving experiments showed that two Chromohalobacter isolates were able to dissolve CaCO3 and one of the Halomonas isolate was able to dissolve both CaCO3 and MgCO3. As these bacterial isolates can dissolve CaCO3 and MgCO3, the availability of Ca2+ and Mg2+ ions may increase which can enhance the removal of the excess Na+ in soil profile. 相似文献
106.
In vitro effects of omeprazole, morphine sulphate, remifentanyl, ketamine and vankomycin were investigated on human red blood cell glucose-6 phosphate dehydrogenase (G-6PD) (E.C. 1.1.1.49) enzyme activity purified from human red blood cell by 2', 5'ADP-Sepharose 4B affinity gel. The obtained I50 values of omeprazole, morphine, remifentanil, ketamine and vankomycin were 3.24, 43.58, 97.6, 64.16 and 0.903 mM, respectively and the Ki constants for omeprazole, morphine and vankomycin were 8.22 +/- 2.055, 25.93 +/- 6.482, and 2.71 +/- 0.677 mM, respectively and they were non competitive inhibitors. 相似文献
107.
There are two highly homologous survival motor neuron (SMN) genes in humans but molecular defects in the SMN1 gene cause spinal muscular atrophy (SMA). More than 90% of SMA patients are shown to have a homozygous deletion of exon 7 in the SMN1 gene. Therefore, a simple test for exon 7 deletion would be very useful in the molecular diagnosis of SMA. However, limited methods are available, and most of these methods utilize expensive instruments and consumables. Here, we describe a simple allele-specific PCR test, which can be performed using standard equipment in DNA laboratories. The principle of the test is based on a single nucleotide difference (C versus T) between the exon 7 of SMN1 and SMN2 genes. Using allele-specific primers, two PCR amplifications are performed for each sample to amplify a 404-bp diagnostic fragment, and consequent electrophoresis of PCR products on agarose gel provides definitive information concerning the exon 7 deletion To rule out false negatives, a 500-bp fragment from the N-acetyltransferase gene was coamplified as an internal control in each test. We have, so far, analyzed 41 SMA samples with our method, and tested the validity of results using an independent restriction fragment length polymorphism (RFLP) method. Genotyping results obtained by both methods were in complete agreement for all of the samples analyzed. Our method can also be used to detect heterozygous deletion of exon 7 in SMN genes, if the relative intensities of the diagnostic and internal control bands are determined. 相似文献
108.
Mutlu MB Martínez-García M Santos F Peña A Guven K Antón J 《FEMS microbiology ecology》2008,65(3):474-483
Tuz Lake is an inland thalassohaline water body located in central Anatolia that contributes to 60% of the total salt production in Turkey per year. The microbiota inhabiting this lake has been studied by FISH, denaturing gradient gel electrophoresis of PCR-amplified fragments of 16S rRNA genes, and 16S rRNA gene clone library analysis. Total cell counts per milliliter (1.38 × 107 ) were in the range of the values normally found for hypersaline environments. The proportion of Bacteria to Archaea in the community detectable by FISH was one to three. 16S rRNA gene clone libraries indicated that the archaeal assemblage was dominated by members of the Square Haloarchaea of the Walsby group, although some other groups were also found. Bacteria were dominated by members of the Bacteroidetes , including Salinibacter ruber -related phylotypes. Because members of Bacteroidetes are widely present in different hypersaline environments, a phylogenetic analysis of 16S rRNA gene sequences from Bacteroidetes retrieved from these environments was carried out in order to ascertain whether they formed a unique cluster. Sequences retrieved from Tuz Lake and a group of sequences from other hypersaline environments clustered together in a branch that could be considered as the 'halophilic branch' within the Bacteroidetes phylum. 相似文献
109.
Balci-Peynircioglu B Waite AL Schaner P Taskiran ZE Richards N Orhan D Gucer S Ozen S Gumucio D Yilmaz E 《Experimental biology and medicine (Maywood, N.J.)》2008,233(11):1324-1333
Familial Mediterranean fever (FMF) is characterized by recurrent attacks of fever and serositis; in some cases, ensuing amyloidosis results in kidney damage. Treatment with colchicine reduces the frequency and severity of FMF attacks and prevents amyloidosis, although the mechanisms behind these effects are unknown. Pyrin, the protein product of the MEFV gene, interacts with ASC, a key molecule in apoptotic and inflammatory processes. ASC forms intracellular speck-like aggregates that presage cell death. Here we show that cell death after ASC speck formation is much slower in nonmyeloid cells than in myeloid cells. Additionally, we demonstrate that colchicine prevents speck formation and show that specks can survive in the extracellular space after cell death. Because we also found that ASC is expressed in renal glomeruli of patients with FMF but not in those of control patients, we posit that high local ASC expression may result in speck formation and that specks from dying cells may persist in the extracellular space where they have the potential (perhaps in association with pyrin) to nucleate amyloid. The fact that speck formation requires an intact microtubule network as shown here could potentially account for the ability of prophylactic colchicine to prevent or reverse amyloidosis in patients with FMF. 相似文献
110.
Mehmet Kahraman Ayse Ozbay Handan Yuksel Ramazan Solmaz Baran Demir Humeyra Caglayan 《Plasmonics (Norwell, Mass.)》2018,13(3):785-795
Surface-enhanced Raman scattering (SERS) is an emerging analytical method used in biological and non-biological structure characterization. Since the nanostructure plasmonic properties is a significant factor for SERS performance, nanostructure fabrication with tunable plasmonic properties are crucial in SERS studies. In this study, a novel method for fabrication of tunable plasmonic silver nanodomes (AgNDs) is presented. The convective-assembly method is preferred for the deposition of latex particles uniformly on a regular glass slide and used as a template for polydimethylsiloxane (PDMS) to prepare nanovoids on a PDMS surface. The obtained nanovoids on the PDMS are used as a mold for AgNDs fabrication. The nanovoids are filled with Ag deposition by the electrochemical method to obtain metallic AgNDs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) are used for characterization of the structural properties of all fabricated AgNDs. The optical properties of AgNDs are characterized with the evaluation of SERS activity of 4-aminothiphonel and rhodamine 6G. In addition to experimental characterizations, the finite difference time domain (FDTD) method is used for the theoretical plasmonic properties calculation of the AgNDs. The experimental and theoretical results show that the SERS performance of AgNDs is strongly dependent on the heights and diameters of the AgNDs. 相似文献