913 research outputs found
MIR10B (microRNA 10b)
Review on MIR10B (microRNA 10b), with data on DNA, on the protein encoded, and where the gene is implicated
Current Approaches to Punctuation in Computational Linguistics
Some recent studies in computational linguistics have aimed to take advantage of various cues presented by punctuation marks. This short survey is intended to summarise these research efforts and additionally, to outline a current perspective for the usage and functions of punctuation marks. We conclude by presenting an information-based framework for punctuation, influenced by treatments of several related phenomena in computational linguistics. © 1997 Kluwer Academic Publishers
The DEAH-box RNA helicase RHAU binds an intramolecular RNA G‐quadruplex in TERC and associates with telomerase holoenzyme
Guanine-quadruplexes (G4) consist of non-canonical four-stranded helical arrangements of guanine-rich nucleic acid sequences. The bulky and thermodynamically stable features of G4 structures have been shown in many respects to affect normal nucleic acid metabolism. In vivo conversion of G4 structures to single-stranded nucleic acid requires specialized proteins with G4 destabilizing/unwinding activity. RHAU is a human DEAH-box RNA helicase that exhibits G4-RNA binding and resolving activity. In this study, we employed RIP-chip analysis to identify en masse RNAs associated with RHAU in vivo. Approximately 100 RNAs were found to be associated with RHAU and bioinformatics analysis revealed that the majority contained potential G4-forming sequences. Among the most abundant RNAs selectively enriched with RHAU, we identified the human telomerase RNA template TERC as a true target of RHAU. Remarkably, binding of RHAU to TERC depended on the presence of a stable G4 structure in the 5′-region of TERC, both in vivo and in vitro. RHAU was further found to associate with the telomerase holoenzyme via the 5′-region of TERC. Collectively, these results provide the first evidence that intramolecular G4-RNAs serve as physiologically relevant targets for RHAU. Furthermore, our results suggest the existence of alternatively folded forms of TERC in the fully assembled telomerase holoenyzm
Magnetic properties of triethylene glycol coated CoFe2O4 and Mn0.2Co0.8Fe2O4 NP's synthesized by polyol method
AbstractIn this study, we reported on the structural and magnetic properties of TEG-CoFe2O4 and TEG-Mn0.2Co0.8Fe2O4 nanocomposites produced by the glycothermal reaction (polyol). X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibration sample magnetometer (VSM) analysis have been carried out in order to understand the effect of Mn2+ into CoFe2O4 and it was observed that the addition of Mn2+ tends to reduce the crystallite size, increase the ao (cell parameter) and increase the TB. The presence of adsorbed polyol entities on the surface of the CoFe2O4 and Mn0.2Co0.8Fe2O4 NP's was also proven by TG measurements. FT-IR analysis suggested the presence of adsorbed TEG molecules on the surface of CoFe2O4 and Mn0.2Co0.8Fe2O4 NP's
Quantitative analysis of regulatory flexibility under changing environmental conditions
The circadian clock controls 24-h rhythms in many biological processes, allowing appropriate timing of biological rhythms relative to dawn and dusk. Known clock circuits include multiple, interlocked feedback loops. Theory suggested that multiple loops contribute the flexibility for molecular rhythms to track multiple phases of the external cycle. Clear dawn- and dusk-tracking rhythms illustrate the flexibility of timing in Ipomoea nil. Molecular clock components in Arabidopsis thaliana showed complex, photoperiod-dependent regulation, which was analysed by comparison with three contrasting models. A simple, quantitative measure, Dusk Sensitivity, was introduced to compare the behaviour of clock models with varying loop complexity. Evening-expressed clock genes showed photoperiod-dependent dusk sensitivity, as predicted by the three-loop model, whereas the one- and two-loop models tracked dawn and dusk, respectively. Output genes for starch degradation achieved dusk-tracking expression through light regulation, rather than a dusk-tracking rhythm. Model analysis predicted which biochemical processes could be manipulated to extend dusk tracking. Our results reveal how an operating principle of biological regulators applies specifically to the plant circadian clock
Autogenous shrinkage properties of high performance cement based products
Yüksek performanslı ve yüksek dayanımlı betonların üretimiyle, otojen rötre kavramı büyük bir önem kazanmıştır. Çimento miktarı yüksek, su/çimento oranı çok düşük seviyelerde olan bu betonlarda yeterince su bulunmamasından dolayı otojen rötrenin salt kimyasal faktör dışında kendiliğinden kurumanın yol açtığı bir fiziksel etkiyle de arttığı gözlenmiştir. Otojen rötrenin yüksek performanslı betonlarda, kuruma rötresi mertebesine erişmesiyle konu ilgi çekmeye başlamış ve konu üzerindeki araştırmalar yoğunlaşmıştır. Çimentoların çeşitli bileşenlerinin, kimyasal ve mineral katkıların bu rötre üzerindeki etkilerinin araştırıldığı çok sayıda araştırma mevcuttur. Portland çimentolarının minör bileşenleri olan alkalilerin, çok düşük miktarlarına karşın betonların işlenebilme, dayanım, dürabilite ve rötre özeliklerini önemli ölçüde etkilediği bilinmektedir. Bu deneysel çalışmada yüksek performanslı betonların otojen rötreleri üzerinde çimento bileşenlerinin (özellikle çözünen alkali içeriğinin) ve süperakışkanlaştırıcı katkının etkileri araştırılmış, bu iki faktörün hidratasyon süreci üzerindeki etkileri üzerine yoğunlaşılmıştır. Çalışmada değişik kimyasal bileşenlere sahip çimentolar kullanılarak hamur numuneler üretilmiş, bu numunelerin otojen rötreleri belirlenmiştir. Bu çimentoların hidratasyon aşamaları da çeşitli yöntemlerle takip edilmiştir. Sonuç olarak çimento bileşenlerinin (özellikle çözünen alkali içeriğinin) ve süperakışkanlaştırıcı kullanımının otojen rötre üzerindeki etkileri belirlenmiştir. Elde edilen ana sonuç şöyle özetlenebilir; çimentolardaki çözünen alkali miktarları FKOR büyüklüğünü arttırma yönünde etkinlik taşımktadır. Bunun yanında C3A, C4AF, (SO3/çözünen alkali oranı) ve incelik parametreleri de FKOR’yi etkileyen etkenler arasında dikkate alınmalıdır. Anahtar Kelimeler: Yüksek performasnlı beton, otojen rötre, hidratasyon, çözünen alkali. Autogenous shrinkage concept has started to gain more importance since the high performance-high strength concretes were began to be utilized for structural purposes. These concretes are generally designed with high cementitious materials contents and low water to cementitious material ratios. It is observed that, due to lack of water in capillary pores in these concretes, autogenous shrinkage increases under the effects of not only the chemical factors but also the physical effects. Autogenous shrinkage has started to draw attention with having the same magnitude of drying shrinkage, and the research dealing with this concept has been intensified. There are numbers of investigations focusing on the effects of various components of cements, chemical and mineral admixtures on this shrinkage. It is well known that, alkalis, which are the minor components of Portland cements, affect the workability, strength, durability, and shrinkage properties of concretes drastically despite their low percentage in cement. These components also affect the hydration process of Portland cement crucially. Therefore, it is inevitable that the soluble alkalis existing in cement will have an effect on the autogenous shrinkage which became more important due to its use in the production of high performance concretes (HPC). Superplasticizers are indispensable ingredients of HPCs. Besides reducing the water to cement ratio, these admixtures also affect the hydration rate and morphology of the hydration products. In this experimental study; effects of cement components (especially soluble alkali content) and superplasticizers on the autogenous shrinkage were investigated. The effects of these two factors on the hydration process were also focused on. Moreover, discussions were done on the definition of autogenous shrinkage. "Physicochemical Autogenous Shrinkage" term was attributed as to define this shrinkage which is mainly caused by physicochemical effects. Cement paste specimens were produced using cements having different chemical compositions. Autogenous shrinkages of these specimens were obtained by means of volumetric measurement technique. Measurements of volumetric changes was taken in water by means of Archimet balance. Hydration degree of these paste specimens were obtained by non-evaporable water technique. Heat of hydration values were also measured by means of semi-adiabadic calorimeter. The rate of hydration reaction was determined. Capillary pore size distributions were also obtained with Mercury Intrusion Porosimeter (MIP) technique. As a result, the effects of cement components (especially soluble alkali content) and superplasticizers on the autogenous shrinkage of HPC's were determined. Moreover, critical time periods for physcochemical autogenous shrinkage were obtained and the characteristic behavior of this shrinkage were exlained by hydration kinetics. Relations between capillary pore ratio and physcochemical autogenous shrinkage were determined. The main results obtained from this experimental study can be drawn as following: 1) Physicochemical autogenous shrinkage has three main phases for the pastes with low water to cement ratios containing superplasticizer. Generally, these stages were not observed for the specimens which do not contain superplasticizer. However, as an exceptional case, some specimens which do not include superplasticizer could show similar steps as the specimens having superplasticizer. 2) Although, lower hydration heats and hydration degrees were obtained for the lower water to cement ratio specimens, higher values of physicochemical autogenous shrinkage were measured. It was determined that the most effective factor in gaining the physicochemical shrinkage was the released heat values which show the rate of hydration. Higher physicochemical autogenous shrinkage values are measured for the cement pastes which have the higher values of released heat. Microporosity test results have shown that the increasing ratio of capillary pores to total pores causes to increase in physicochemical autogenous shrinkage. Soluble alkali contents were also found to be effective on the. Cements having higher soluble alkali contents exhibited higher physicochemical autogenous shrinkage. It was also concluded that besides the soluble alkali contents in cement, C3A, C4AF contents and SO /soluble alkali ratio are effective parameters and they should be taken into consideration. Keywords: High performance concrete, autogenous shrinkage, hydration, soluble alkali
Ecology & computer audition: applications of audio technology to monitor organisms and environment
Among the 17 Sustainable Development Goals (SDGs) proposed within the 2030 Agenda and adopted by all the United Nations member states, the 13th SDG is a call for action to combat climate change. Moreover, SDGs 14 and 15 claim the protection and conservation of life below water and life on land, respectively. In this work, we provide a literature-founded overview of application areas, in which computer audition – a powerful but in this context so far hardly considered technology, combining audio signal processing and machine intelligence – is employed to monitor our ecosystem with the potential to identify ecologically critical processes or states. We distinguish between applications related to organisms, such as species richness analysis and plant health monitoring, and applications related to the environment, such as melting ice monitoring or wildfire detection. This work positions computer audition in relation to alternative approaches by discussing methodological strengths and limitations, as well as ethical aspects. We conclude with an urgent call to action to the research community for a greater involvement of audio intelligence methodology in future ecosystem monitoring approaches
Simple sequence repeat-based assessment of genetic diversity in 'Dimrit' and 'Gemre' grapevine accessions from Turkey
It is widely believed that Turkey has played an important role in the evolution of modern day grapes due to its unique geographical location with close proximity to the regions of grape diversity. Despite this, the rich grape germplasm found in Turkey has not been sufficiently analyzed genetically. In this study, 31 grapevine accessions from 'Dimrit' (or 'Dilmit') and 'Gemre' grape groups were genetically analyzed at eight SSR (microsatellite) loci (VVS2, VVMD5, VVMD7, VVMD24, VVMD27, VVMD28, VrZAG62 and VrZAG79) and for a number of ampeolographic characteristics. These analyses identified sufficient genetic diversity between these two grape groups that, in general, clustered separately in the dendrogram constructed based on the SSR data. However, the ecogeographical distribution and genetic relationship of the genotypes did not show any significant correlation. Two 'Gemre' accessions were determined as genetically identical. In addition, one case of synonym and several cases of homonym genotypes were identified. The results reported here are important first steps towards better characterization of these grape genotypes and would aid future germplasm management and breeding efforts.
Non-Commutative Batalin-Vilkovisky Algebras, Homotopy Lie Algebras and the Courant Bracket
We consider two different constructions of higher brackets. First, based on a
Grassmann-odd, nilpotent \Delta operator, we define a non-commutative
generalization of the higher Koszul brackets, which are used in a generalized
Batalin-Vilkovisky algebra, and we show that they form a homotopy Lie algebra.
Secondly, we investigate higher, so-called derived brackets built from
symmetrized, nested Lie brackets with a fixed nilpotent Lie algebra element Q.
We find the most general Jacobi-like identity that such a hierarchy satisfies.
The numerical coefficients in front of each term in these generalized Jacobi
identities are related to the Bernoulli numbers. We suggest that the definition
of a homotopy Lie algebra should be enlarged to accommodate this important
case. Finally, we consider the Courant bracket as an example of a derived
bracket. We extend it to the "big bracket" of exterior forms and multi-vectors,
and give closed formulas for the higher Courant brackets.Comment: 42 pages, LaTeX. v2: Added remarks in Section 5. v3: Added further
explanation. v4: Minor adjustments. v5: Section 5 completely rewritten to
include covariant construction. v6: Minor adjustments. v7: Added references
and explanation to Section
First generation immigrant judgements of offence seriousness: evidence from the crime survey for England and Wales
This exploratory paper delves into differences and similarities in the rated seriousness of offences suffered by victims of different national origin. The issue is important because a mismatch between police and victim assessments of seriousness is likely to fuel discord. It was found that first generation immigrants did not differ in their rating of the seriousness of offences against the person from either the indigenous population or according to region of birth. However those of Asian origin rated vehicle and property crime they had suffered as more serious than did other groups about crimes they suffered. The anticipated higher seriousness rating of offences reported to the police r was observed for all groups. People of Asian origin reported to the police a smaller proportion of offences they rated trivial than did people in other groups. Analysis of seriousness judgements in victimization surveys represents a much-underused resource for understanding the nexus between public perceptions and criminal justice responses
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