Writing a wrong: Coupled RNA polymerase II transcription and RNA quality control

Processing and maturation of precursor RNA species is coupled to RNA polymerase II transcription. Co-transcriptional RNA processing helps to ensure efficient and proper capping, splicing, and 3' end processing of different RNA species to help ensure quality control of the transcriptome. Many improperly processed transcripts are not exported from the nucleus, are restricted to the site of transcription, and are in some cases degraded, which helps to limit any possibility of aberrant RNA causing harm to cellular health. These critical quality control pathways are regulated by the highly dynamic protein-protein interaction network at the site of transcription. Recent work has further revealed the extent to which the processes of transcription and RNA processing and quality control are integrated, and how critically their coupling relies upon the dynamic protein interactions that take place co-transcriptionally. This review focuses specifically on the intricate balance between 3' end processing and RNA decay during transcription termination. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Processing > 3' End Processing RNA Processing > Splicing Mechanisms RNA Processing > Capping and 5' End Modifications

Field dependence of the magnetocaloric effect in Gd and (Er 1-xDyx)Al2: Does a universal curve exist?

The field dependence of the magnetic entropy change of ferromagnetic lanthanide- based materials has been studied. The recently proposed master curve for the field dependence of the magnetocaloric effect of Fe-based amorphous alloys can also be constructed for these lanthanide-based crystalline materials, suggesting a universal behavior. The exponent n controlling the field dependence of the magnetic entropy change can be used for the interpretation of results in the case of multiple magnetic ordering phenomena

Correlations between Elastic, Calorimetric, and Polar Properties of Ferroelectric PbSc0.5Ta0.5O3 (PST)

Calorimetric, elastic, and polar properties of ferrolectric lead scandium tantalate PbSc0.5Ta0.5O3 (PST) with 65% cation order have been investigated in the vicinity of the paraelectric-ferroelectric transition at Ttrans = 295K. Comparison of temperature dependencies of the excess specific heat and elastic properties indicate that both anomalies stem from ther- mal fluctuations of order parameters in three dimensions. These fluctuations are consistent with tweed microstructure. This transition is driven by several coupled thermodynamic order parameters, as evidenced by a strongly non-linear scaling of the excess entropy with the squared ferroelectric polarization.National Natural Science Foundation of China (51850410520, 51320105014 and 51621063

Characterization of the magnetic interactions of multiphase magnetocaloric materials using first-order reversal curve analysis

In order to understand the magnetocaloric response of materials, it is important to analyze the interactions between the different phases present in them. Recent models have analyzed the influence of these interactions on the magnetocaloric response of composites, providing an estimate value of the interaction field that is consistent with experimental results. This paper analyzes to which extent magnetization first-order reversal curve (FORC) method can be used to calculate these interactions. It is shown that the different field ranges that are explored using these techniques (inside the hysteretic region for FORC; close to magnetic saturation for magnetocaloric effect) produce interaction field values that differ in order of magnitude, with FORC being sensitive to the lower values of the interaction field and magnetocaloric analysis accounting for the larger interactions

Influence of Co and Ni addition on the magnetocaloric effect in Fe88−2xCoxNixZr7B4Cu1 soft magnetic amorphous alloys

We have studied the magnetocaloric effect in a series of Fe88−2xCoxNixZr7B4Cu1Fe88−2xCoxNixZr7B4Cu1alloys. The partial substitution of Fe by Co and Ni leads to a monotonic increase in the Curie temperature(TC)(TC) of the alloys from 287 K for x=0x=0 to 626 K for x=11x=11. The maximum magnetic entropy change (ΔSpkM)(ΔSMpk) at an applied field of 1.5 T, shows a value of 1.98 J K−1 kg−11.98 J K−1 kg−1 for x=8.25x=8.25. The refrigerant capacity (RC) has maximum values near 166 J kg−1166 J kg−1 (for x=0x=0 and 2.75). These values place the present series of alloys among the best magnetic refrigerant materials, with an RC ∼40%∼40% larger than Gd5Si2Ge1.9Fe0.1Gd5Si2Ge1.9Fe0.1 and ∼15%∼15% larger than Fe-based amorphousalloys

Magnetocaloric effect and critical exponents of Fe77Co 5.5Ni5.5Zr7B4Cu1: A detailed study

The critical exponents of the alloy have been determined with the Kouvel–Fisher method to predict the field dependence of the magnetic entropy change DSM . The nonlinear fit of DSM ðHÞ to a power law provides a field exponent in perfect agreement with the predictions of the relevant scaling laws using the obtained critical exponent values. It is shown that possible discrepancies between these two methods for determining the field dependence of DSM might arise due to a poor resolution in the temperature of the experiments

Optimization of the refrigerant capacity in multiphase magnetocaloric materials

The refrigerant capacity (RC) of magnetocaloric materials can be enhanced using multiphase materials or composites, which expand the temperature range over which a significant magnetic entropy change can be obtained. Numerical simulations show that by controlling the parameters of the composite (the fraction of the different phases and their Curie temperatures) improvements of RC of ∼83% are possible. The maximum applied field plays a crucial, nonmonotonic, role in the optimization. As a proof of concept, it is shown that the combination of two Fe88−2xCoxNixZr7B4Cu1 alloys produces an enhancement in RC of ∼37%, making it ∼92% larger than that of Gd5Si2Ge1.9Fe0.

Guatemala: cultura tradicional y sostenibilidad

This article has the objective of delving into the relationship there is between nature and culture, for the particular case of Guatemala. With this aim, we describe in detail a journey through Guatemala’s history, the ethnic identities of its inhabitants, and the cultural characteristics of these. In particular, emphasis is made on the normative scope of indigenous culture and spirituality of Mayan ancestry, in relation to the management of their natural resources expressed in the levels of environmental sustainability attained. Also described, in general terms, are the conservation strategies for Guatemala’s natural resources and the scarce results in containing their deterioration. The need to establish an inter-ethnic dialogue is highlighted, that could make possible rescuing, validating and incorporating the indigenous Mayan vision to those strategies, in search for the design and implementation in Guatemala of an authentic ecological current that recognizes and promotes the local efforts to conserve nature, with a multi-cultural approach.El presente artículo tiene por objetivo profundizar en la relación existente entre naturaleza y cultura, para el caso particular guatemalteco. Con tal fin se detalla un recorrido por la historia guatemalteca, las identidades étnicas de sus habitantes, así como las características culturales de los mismos. Especialmente, se enfatiza sobre el ámbito normativo de la cultura y espiritualidad indígena de ascendencia maya, en relación con el manejo de sus recursos naturales, expresada en los niveles de sostenibilidad ambiental conseguidos. Se describe también, en términos generales, las estrategias de conservación de los recursos naturales de Guatemala y el escaso resultado en contener el deterioro de los mismos. Se resalta la necesidad de establecer un diálogo interétnico que posibilite rescatar, validar e incorporar a dichas estrategias la visión indígena maya, en la búsqueda del diseño e implementación en Guatemala de una auténtica corriente ecológica que reconozca y promueva los esfuerzos locales por conservar la naturaleza, con un enfoque multicultural

Using sap flow measurements to estimate net assimilation in olive trees under different irrigation regimes

The measurement of bulk net assimilation (A) in fruit tree species is hindered by the need for sophisticated and complex instrumentation. The aim of this study is to present a simple alternative for estimating A from sap flow measurements and meteorological records. The proposed method was tested in a mature hedgerow olive orchard of 22.2 ha. Within the orchard, an irrigation experiment was established in a small plot including three treatments: a full irrigated control (CI), a regulated deficit irrigation (DI) and one additional treatment mimicking the customary orchard irrigation management (FI). Determinations of sap flow, water potential (Ψ) and trunk diameter variations (TDV) were conducted in the three treatments for three years. Also, measurements of net ecosystem exchange (NEE) were performed with an eddy covariance system in the centre of the orchard for the first season. The validity of the method was supported by the fact that our estimates of A were consistent with both the measured values of NEE and published data on the same species under similar environmental and management conditions. Also, differences in A between irrigation treatments were generally coherent with the ones in irrigation applied, transpiration (Ep), Ψ and TDV. It is concluded that the proposed sap flow-based method represents a user-friendly approach to estimate A at the canopy-level with potential to study the effects of deficit irrigation on biomass accumulation