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71.
Bee disease caused by spore-forming Paenibacillus larvae and Paenibacillus alvei is a serious problem for honey production. Thus, there is an ongoing effort to find an effective agent that shows broad biocidal activity with minimal environmental hazard. In this study, the biocidal effect of maltose reduced silver nanoparticles (AgNPs) is evaluated against American foulbrood and European foulbrood pathogens. The results demonstrate that the maltose reduced AgNPs are excellent short and long-term biocides against P. larvae isolates. The long-term effect suggests that the Ag+ ions are released from the AgNPs with increasing time in a controlled manner.  相似文献   
72.
The present study investigated the effects of gas-tight and gas-permeable culture containers and different sucrose concentrations, as well as sucrose and mannitol combinations on the development of an effective in vitro slow growth storage protocol (at 4 °C, in darkness) for ‘Gisela®5’ shoot cultures. ‘Gisela®5’ is the most widely used cherry rootstock in Europe. This dwarf triploid hybrid has many advantages over the conventional cherry rootstocks. Optimizations for the cold storage of ‘Gisela®5’ in vitro shoot cultures included use of storage medium supplemented with 10, 20, 30, 45, and 60 g L?1 sucrose and sucrose (15, 30 g L?1) and mannitol (15 g L?1) combinations, contained in gas-tight glass jars and gas-permeable ‘Star Pac?’ bags. Cold storage was prolonged to 12 months, during which in every 3 months, cultures were evaluated. Possibility of 16 month-cold storage in gas-tight glass jars was also explored, during which gas chromatographic analysis was performed for the detection of CO2 and ethylene accumulation for the first 5 months of cold storage. Our results showed that both the 12- and 16-month conservations were possible, especially when 45 or 60 g L?1 sucrose was supplemented to storage medium, contained in glass jars. Mannitol inclusion to the storage medium was also effective to reduce the metabolic activity of the shoot cultures during storage; however, it did not have a significant positive influence on shoot quality in post-conservation.  相似文献   
73.
ABSTRACT

This article analyses network organizations founded by descendants of Turkish migrants in the Netherlands and France. By surveying members of two such organizations and interviewing several of their board members, we learn how these organizations function, their success in building and extending social networks, and their efficacy at improving labour market prospects for young second-generation professionals of Turkish descent. Our findings reveal a hybrid structure, whereby the organizations gear many of their activities towards mainstream society. In comparison to traditional immigrant organizations, their attitude is more open to other social groups, yet they still have a clear stronghold in the ethnic immigrant community. We conclude that ethnicity is not the main element in the successful second generation’s organizing process. Factors such as educational trajectories, professional ambitions, feelings of responsibility for other members and newly acquired socioeconomic status are the main reasons for this group to organize.  相似文献   
74.
Sleep and Biological Rhythms - This study aimed to identify the symptoms and prevalence of snoring among primary school children in Ankara, Turkey, as reported by their parents and to determine the...  相似文献   
75.
Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disorder with the responsible gene of MEFV which primarily affects Jewish, Armenian, Turkish and Arab populations. The FMF gene (MEFV) has recently been cloned to chromosome 16p, which encodes pyrin. In the present study, we enrolled 2,067 unrelated patients with the suspicion of FMF in Middle Anatolia between the years 2006–2009 and identified the 12 MEFV mutations. DNA was amplified by PCR and subjected to reverse hybridization for the detection of MEFV gene mutations. Among the 2,067 patients, 866 (41.9%) were males and 1,201 (58.1%) were females. The mutations were homozygous in 176 (16.85%) patients, compound heterozygous in 314 (30.1%) patients, heterozygous in 546 (52.25%) patients and the other forms of mutations were found in 8 patients (0.76%). No mutation was detected in 1,023 (49.5%) patients. The most frequent mutations were M694V, M680I (G/C), E148Q and V726A. We could not find any significant differences between the two common mutations according to the gender. The high incidence of MEFV gene mutations in the Turkish population indicated that newborn screening may be discussed in the future. Because of the ethnic origin of Anatolia, larger serial analyses are necessary to investigate the rate and coexistence of these mutations.  相似文献   
76.
Sequence similarity tools, such as BLAST, seek sequences most similar to a query from a database of sequences. They return results significantly similar to the query sequence and that are typically highly similar to each other. Most sequence analysis tasks in bioinformatics require an exploratory approach, where the initial results guide the user to new searches. However, diversity has not yet been considered an integral component of sequence search tools for this discipline. Some redundancy can be avoided by introducing non-redundancy during database construction, but it is not feasible to dynamically set a level of non-redundancy tailored to a query sequence. We introduce the problem of diverse search and browsing in sequence databases that produce non-redundant results optimized for any given query. We define diversity measures for sequences and propose methods to obtain diverse results extracted from current sequence similarity search tools. We also propose a new measure to evaluate the diversity of a set of sequences that is returned as a result of a sequence similarity query. We evaluate the effectiveness of the proposed methods in post-processing BLAST and PSI-BLAST results. We also assess the functional diversity of the returned results based on available Gene Ontology annotations. Additionally, we include a comparison with a current redundancy elimination tool, CD-HIT. Our experiments show that the proposed methods are able to achieve more diverse yet significant result sets compared to static non-redundancy approaches. In both sequence-based and functional diversity evaluation, the proposed diversification methods significantly outperform original BLAST results and other baselines. A web based tool implementing the proposed methods, Div-BLAST, can be accessed at cedar.cs.bilkent.edu.tr/Div-BLAST  相似文献   
77.
Ecosystems are interconnected by energy fluxes that provide resources for the inhabiting organisms along the transition zone. Especially where in situ resources are scarce, ecosystems can become highly dependent on external resources. The dependency on external input becomes less pronounced in systems with elevated in situ production, where only consumer species close to the site of external input remain subsidized, whereas species distant to the input site rely on the in situ production of the ecosystem. It is largely unclear though if this pattern is consistent over different consumer species and trophic levels in one ecosystem, and whether consumer species that occur both proximate to and at a distance from the input site differ in their dependency on external resource inputs between sites. Using stable isotope analysis, we investigated the dependency on external marine input for common ground‐associated consumer taxa on small tropical islands with high in situ production. We show that marine input is only relevant for strict beach‐dwelling taxa, while the terrestrial vegetation is the main carbon source for inland‐dwelling taxa. Consumer species that occurred both close (beach) and distant (inland) to the site of marine input showed similar proportions of marine input in their diets. This supports earlier findings that the relevance of external resources becomes limited to species close to the input site in systems with sufficient in situ production. However, it also indicates that the relevance of external input is also species‐dependent, as consumers occurring close and distant to the input site depended equally strong or weak on marine input.  相似文献   
78.
Protein tyrosine kinases (PTKs) play an important role in T cell development and activation. In vitro and in vivo defects, resulting in variable deficiencies in thymic development and in T cell antigen receptor (TCR) signal transduction, in PTKs have been shown. ZAP70, one of those PTKs, is a 70-kDa tyrosine phosphoprotein and associates with the ζ chain and undergoes tyrosine phosphorylation following TCR stimulation. It is expressed in T and natural killer (NK) cells. Several mutations were shown to lead to an autosomal recessive form of severe combined immunodeficiency disease (SCID).  相似文献   
79.
Intracellular signaling mechanisms in red blood cells (RBCs) involve various protein kinases and phosphatases and enable rapid adaptive responses to hypoxia, metabolic requirements, oxidative stress, or shear stress by regulating the physiological properties of the cell. Protein phosphorylation is a ubiquitous mechanism for intracellular signal transduction, volume regulation, and cytoskeletal organization in RBCs. Spectrin-based cytoskeleton connects integral membrane proteins, band 3 and glycophorin C to junctional proteins, ankyrin and Protein 4.1. Phosphorylation leads to a conformational change in the protein structure, weakening the interactions between proteins in the cytoskeletal network that confers a more flexible nature for the RBC membrane. The structural organization of the membrane and the cytoskeleton determines RBC deformability that allows cells to change their ability to deform under shear stress to pass through narrow capillaries. The shear stress sensing mechanisms and oxygenation-deoxygenation transitions regulate cell volume and mechanical properties of the membrane through the activation of ion transporters and specific phosphorylation events mediated by signal transduction. In this review, we summarize the roles of Protein kinase C, cAMP-Protein kinase A, cGMP-nitric oxide, RhoGTPase, and MAP/ERK pathways in the modulation of RBC deformability in both healthy and disease states. We emphasize that targeting signaling elements may be a therapeutic strategy for the treatment of hemoglobinopathies or channelopathies. We expect the present review will provide additional insights into RBC responses to shear stress and hypoxia via signaling mechanisms and shed light on the current and novel treatment options for pathophysiological conditions.  相似文献   
80.
Borrelia burgdorferi infection is the most frequent tick-transmitted disease worldwide. Our aim was to assess the seroprevalence of B. burgdorferi infection among forestry workers and farmers in Duzce, in the north-west region of Turkey. Blood samples from 349 forestry workers and farmers and 193 healthy blood donors were obtained to determine the presence of antibodies to B. burgdorferi. A two-step testing strategy was used; the sera were initially tested by ELISA and then by Western blot (WB) IgG. Demographic data regarding residence, age, gender, profession, tick bite history, contact with animals, and symptoms involving the skin, nervous system, and osteoarticular system were collected by questionnaire. All results were evaluated statistically using the chi2 test. The seroprevalence of B. burgdorferi was 10.9% (n=38) in forestry workers and farmers and 2.6% (n=5) in blood donors by ELISA, with a statistically significant difference (p<0.001). Seropositivity rates were related to age, gender, and common risk factors for the disease. IgG seropositivity was confirmed in four (1.1%) sera by WB. In this first seroepidemiological report from the northwest region of Turkey, tick bite exposure was found to be high, whereas B. burgdorferi infection was not common. Preventive measures against tick exposure and further studies to determine the distribution of Lyme disease in Turkey are proposed.  相似文献   
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