The mTORC1 (mechanistic target of rapamycin complex 1) protein kinase regulates growth in response to nutrients and growth factors. Nutrients promote its translocation to the lysosomal surface, where ...its Raptor subunit interacts with the Rag guanosine triphosphatase (GTPase)-Ragulator complex. Nutrients switch the heterodimeric Rag GTPases among four different nucleotide-binding states, only one of which (RagA/B•GTP-RagC/D•GDP) permits mTORC1 association. We used cryo-electron microscopy to determine the structure of the supercomplex of Raptor with Rag-Ragulator at a resolution of 3.2 angstroms. Our findings indicate that the Raptor α-solenoid directly detects the nucleotide state of RagA while the Raptor "claw" threads between the GTPase domains to detect that of RagC. Mutations that disrupted Rag-Raptor binding inhibited mTORC1 lysosomal localization and signaling. By comparison with a structure of mTORC1 bound to its activator Rheb, we developed a model of active mTORC1 docked on the lysosome.
•External Convective heat transfer coefficients and radiative ones were calculated through different correlations.•Dissimilarities among the different coefficients values were investigated.•Heat flow ...meter and temperature probes were used to evaluate total heat transfer coefficients.•Convective and radiative components were distinctly assessed in two case studies.•Peculiar building features (balconies and porticos) were addressed.
In the building sector, the assessment of heat transfer processes is essential to identify the performance of structural elements. Heat transfer occurring in internal and external environments between walls and surrounding bodies is quantified by means of convective and radiative coefficients able to summarize physical phenomena. In building applications, International Standards suggest to calculate thermal transmittances by proposing specific surface thermal resistance values.
Moreover, several equations have been developed in scientific literature to compute the convective and radiative heat transfer coefficients, particularly useful in the building simulation field. For what concerns external coefficients, these correlations are generally related to the wind velocity, wind direction (windward and leeward surfaces) and surface roughness.
In this paper, the actual total external heat transfer coefficients in different case studies were obtained by measuring the physical parameters needed to define them. Peculiar geometries, i.e. balconies and porticos, were addressed, for which specific correlations are not available in literature. Convective and radiative components were distinctly assessed and, finally, actual convective heat transfer coefficients were compared with the same coefficients obtained by applying the conventional correlations available in literature and with the constant value suggested by the Standard. In addition, the convective heat transfer coefficients were evaluated by means of empirically determined correlations based on dimensionless parameters. The final goal of this work is to investigate the dissimilarities among the different coefficients values, in order to analyze applicability and limits of UNI EN ISO 6946 and of existing correlations for external heat transfer coefficients.
The analysis of the coefficients shows that the most significant differences are related to the convective heat transfer phenomena quantification. Applying the same correlations to different case studies scattered results were obtained whereas employing the dimensionless numbers correlations small oscillations in both case studies can be observed.
•We explored how changes in climate may affect the spatial distribution of areas suitable for coffee production in 2050.•The area suitable for coffee production with unshaded plantations may decline ...by 60% under projected climate change.•Agroforestry systems can mitigate the effects of climate change and maintain 75% of the area suitable for coffee production.•Identifying coffee production areas that are vulnerable to climate change may direct climate adaptation management actions.
Climate change may impose severe challenges to farmers to maintain agricultural production levels in the future. In this study we analysed the effect of projected changes in climate on the area suitable for coffee production in 2050, and the potential of agroforestry systems to mitigate these effects in a major coffee production region in southeast Brazil. We conducted a spatially explicit analysis with the bioclimatic model MaxEnt to explore the area that is suitable for coffee production in 2050 when coffee is grown in unshaded plantations and in agroforestry systems. The projected climate in 2050 was assessed using 19 global circulation models, and we accounted for the altered microclimate in agroforestry systems by adjusting the maximum and minimum air temperature. The climate models indicated that the annual mean air temperature is expected to increase 1.7 °C ± 0.3 in the study region, which will lead to almost 60 % reduction in the area suitable for coffee production in unshaded plantations by 2050. However, the adoption of agroforestry systems with 50 % shade cover can reduce the mean temperatures and maintain 75 % of the area suitable for coffee production in 2050, especially between 600 and 800 m altitude. Our study indicates that major shifts in areas suitable for coffee production may take place within three decades, potentially leading to land conflicts for coffee production and nature conservation. Incentives that contribute to the development of coffee agroforestry systems at appropriate locations may be essential to safeguard coffee production in the southeast of Brazil.
The paper presents a comparison between two different rating systems to evaluate buildings sustainability: LEED (USA) and ITACA (Italy), thanks to the application of both methods to two residential ...buildings located in Italy.
The LEED green building rating system encourages an integrated design approach, with a points scheme that allots credits for building design features deemed to improve sustainability, which includes reductions in energy use, improvements in indoor environment quality, protection of the construction site, reduction in water consumption and use of sustainable materials.
ITACA procedure, the environmental quality rating system adopted in Italy, consists of the compilation of a group of worksheets, one for each different performance indicator, at the aim of describing the building environmental quality, including the maintenance of indoor comfort during the entire life cycle.
The chosen buildings are located in central Italy; they are both energy efficient and designed according to the principles of bioclimatic architecture, even if they are characterized by different features. Five common areas (site, water, energy, materials, indoor environmental quality) were identified in order to compare the two methods and to normalize their score; this original approach can be transferred also to the comparison of other building environmental assessment tools.
The comparison allows to prove the main features of both schemes. Even though the two procedures give different importance to the various areas, the analysis show a proportionality between the respective normalized final score for the two examined buildings.
•A comparison between green building rating systems ITACA and LEED was performed.•Analyses applied to 2 green buildings allowed to compare normalized rating scores.•No important technical differences between the two methods of certification emerged.
Nearly 2.5 billion smallholders cultivate the world's arable land, strategically positioned to tackle multiple Anthropocene challenges. When consciously adopting ecologically-based pest management ...practices, they can improve resource use efficiency, slow biodiversity loss, curtail environmental pollution and safeguard human health. Yet, the effective implementation of knowledge-intensive management practices requires underlying ecological concepts to be well-understood. Here, drawing upon published social science research spanning 1910-2016, we illuminate deficiencies in the world's farmers' ecological literacy and in their valuation of insect-mediated ecosystem services. Though tribal people and indigenous folk possess sophisticated knowledge of insects that occur within farm settings, contemporary farmers on average know a mere 1.9-2.3 pestiferous herbivores and 0.5-0.9 pest-killing organisms (out of a respective 8 and 3 taxa) in a particular crop or cropping system. Ecosystem services such as biological pest control are annually worth hundreds of dollars ha−1 but remain unknown to nearly 70% of farmers globally. Also, agricultural systems with deficient ecological literacy tend to foster a greater dependency upon chemically-synthesized pesticides. If this 'cognitive handicap' can be remediated, farmers could become agro-biodiversity stewards and champions in redressing multiple aspects of global environmental change.
•Analysis of 2D and 3D simulations on wood and aluminum windows.•Comparison between simulated and measured thermal properties of windows.•Thermography helps to explain differences between simulation ...and experimental data.•Numerical simulations underestimate windows performance because of stratification.•Hot box measurements value high performance windows better than simulations.
The correct estimation of the energy performance of windows represents a fundamental issue in the buildings heat losses assessment, since both accuracy and simplicity requirements have to be fulfilled.
The most common approaches proposed consist of finite element simulations and laboratory measurements. The reliability of numerical methods results is still an open issue: the general policy of Standards requires for the calculated values to be on the safer side but it is not clear if this assumption is always verified and which is the difference between measured and simulated values. Standards allow the implementation of numerical simulations also in a two-dimensional domain, while windows are composed by zones with a definite three-dimensional geometry such as corners.
Two types of windows (wood and aluminum framed) were analyzed, showing that the difference between two-dimensional and three-dimensional simulations is not so high to justify the vast difference that exists instead in terms of calculation time.
By means of a hot box apparatus, a comparison term was given to evaluate the finite volumes method adherence to the experimental values. Infrared thermography gives the possibility of a better understanding of the differences between the simulation results and the measured values.
The experimental measurements indicated a good data coincidence with simulations for both types of windows, with an expected thermal window performance underestimation of the numerical approach. The reasons lie in the use of thermal conductivity cautionary values in simulations, and on the stratification phenomenon (highlighted by the infrared camera), that brings a decrease to the convection heat transfer. It emerges therefore that, if a window manufacturer strives for achieving high performance certified products, the test on an experimental hot box setup becomes more appropriate, since it brings to a thermal resistance evaluation around 10% higher than the one obtained from a simulation procedure.
Oral mechanoreception is implicated in fundamental functions including speech, food intake and swallowing; yet, the neuroanatomical substrates that encode mechanical stimuli are not well understood. ...Tactile perception is initiated by intricate mechanosensitive machinery involving dedicated cells and neurons. This signal transduction setup is coupled with the topology and mechanical properties of surrounding epithelium, thereby providing a sensitive and accurate system to detect stress fluctuations from the external environment. We mapped the distribution of anatomically distinct neuronal endings in mouse oral cavity using transgenic reporters, molecular markers and quantitative histomorphometry. We found that the tongue is equipped with an array of putative mechanoreceptors that express the principal mechanosensory channel Piezo2, including end bulbs of Krause innervating individual filiform papillae and a novel class of neuronal fibers innervating the epithelium surrounding taste buds. The hard palate and gums are densely populated with three classes of sensory afferents organized in discrete patterns including Merkel cell-neurite complexes, Meissner's corpuscles and glomerular corpuscles. In aged mice, we find that palatal Merkel cells reduce in number at key time-points that correlate with impaired oral abilities, such as swallowing and mastication. Collectively, this work identifies the mechanosensory architecture of oral tissues involved in feeding.
While the area of organic crop production increases at a global scale, the potential interactions between pest management in organic and conventionally managed systems have so far received little ...attention. Here, we evaluate the landscape-level co-dependence of insecticide-based and natural enemy-based pest management using a simulation model for parasitoid-host interactions in landscapes consisting of conventionally and organically managed fields. In our simulations conventional management consists of broad-spectrum or selective insecticide application, while organic management involves no insecticides. Simulations indicate that insecticide use can easily result in lose-lose scenarios whereby both organically and conventionally managed fields suffer from increased pest loads as compared to a scenario where no insecticides are used, but that under some conditions insecticide use can be compatible with biocontrol. Simulations also suggest that the pathway to achieve the insecticide reduction without triggering additional pest pressure is not straightforward, because increasing the proportion of organically managed fields or reducing the spray frequency in conventional fields can potentially give rise to dramatic increases in pest load. The disruptive effect of insecticide use, however, can be mitigated by spatially clustering organic fields and using selective insecticides, although the effectiveness of this mitigation depends on the behavioral traits of the biocontrol agents. Poorly dispersing parasitoids and parasitoids with high attack rates required a lower amount of organically managed fields for effective pest suppression. Our findings show that the transition from a landscape dominated by conventionally managed crops to organic management has potential pitfalls; intermediate levels of organic management may lead to higher pest burdens than either low or high adoption of organic management.
The occurrence of emerging contaminants is becoming of increasing importance to assess the impact of anthropogenic activities onto the environment. The present study reports for the first time the ...development and validation of an efficient method for the simultaneous determination of fragrance materials in water samples based on the use of a novel multiwalled carbon nanotubes (MWCNTs)-based solid-phase microextraction coating. Helical MWCNTs were selected as adsorbent material due to their outstanding extraction performance. The multicriteria method of desirability functions allowed the optimization of the experimental conditions in terms of extraction time and extraction temperature. Validation proved the reliability of the method for the determination of the analytes at ultra-trace levels, obtaining detection limits in the 0.2–13 ng/L range, good precision, with relative standard deviations lower than 20% and recovery rates in the 80 ± 12%–111 ± 11%. Superior enrichment factors compared to commercial fibers were also calculated. Finally, applicability to real sample analysis was demonstrated.
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•Efficient SPME-GC-MS method for trace analysis of fragrance materials in water.•Helical carbon nanotubes-based SPME coating for efficient fragrances extraction.•Completely automatized method requiring reduced sample handling and volumes.•Detection and quantitation limits at low ng/l levels.
Natural and bio-based construction materials represent a promising solution for optimizing buildings' environmental sustainability. In this view, the paper presents the multipurpose experimental ...thermo-acoustic characterization of common reed-based building panels. Different geometries, densities, humidity rates and stalk shapes were considered and tested by means of hot-plate, hot-box and impedance tube in-lab experimental benches. The thermal analysis showed that the geometry scarcely affects the thermal conductivity, which is around 0.05 W/mK and, therefore, comparable to other materials already commercialized for the same scope. On the other hand, the acoustic behavior is strongly affected by the stalk configuration, e.g. perpendicular, parallel or combined orientation with respect to the incident wave. In particular, the longitudinal stalk layout showed a significant sound absorption performance. The exhaustive experimental original characterization of such by-product, therefore, showed a very promising overall thermo-acoustic behavior. At the same time, for optimizing the panel field performance, the acoustic requirements should represent the panel design drivers, given the high sensitivity of the panel layout characteristics affecting the acoustic performance.
•Experimental thermo-acoustic characterization of new bio-based panels was performed.•New common reed materials showed promising performance for building applications.•Thermal conductivity resulted around 0.05 W/mK, comparable with market products.•Sound absorption coefficient resulted high in a wide frequency range.•Acoustic behavior was affected by stalks' geometry.
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