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Electroless Pore-Plated (ELP-PP) membranes were successfully incorporated for the first time into a membrane reactor to produce hydrogen by acetic acid steam reforming (AASR), exhibiting adequate resistance against harsh operating conditions. Membranes were prepared onto tubular PSS supports modified with Pd/CeO 2 particles and scaled-up around four times in length with high reproducibility respect previous studies. H 2 permeances from 4.49 to 5.67·10−4 mol m−2 s−1 Pa-0.5 were found for pure H 2 at 350–450 °C, decreasing for mixtures due to concentration-polarization at higher pressures but also certain inhibition caused by CO 2 at pressures below 50 Pa0.5. The combination of membranes with Ni/SBA-15 catalysts in packed-bed membrane reactors (PBMR) evidenced the simultaneous improvement of acetic acid conversion and hydrogen yield respect to analogous experiments in traditional packed-bed reactors (PBR). A very similar product distribution was obtained for both configurations, PBR and PBMR, when using fresh catalysts, although marked deviations were found in case of regenerating the catalysts. Then, higher selectivity towards coke reached for PBMR, which lead to around 30% for the most elevated pressure under investigation. However, even at these harsh conditions, the mechanical integrity of ELP-PP membranes was maintained. Thus, the benefits of combining catalysts and ELP-PP membranes in a PBMR for AASR were demonstrated. • Successful scale-up of an ELP-PP membrane with Pd/CeO 2 barrier to 110 mm in length. • Pd thickness around 15 μm with no marked differences along the axial direction. • H 2 permeances from 4.49 to 5.67·10−4 mol·m−2·s−1·Pa-0.5 for pure H 2 at 350–450 °C. • Noticeably inhibition caused by CO 2 was found in permeation tests with mixtures. • Mechanical integrity of ELP-PP membrane in PBMR and improvement of H 2 production. [ABSTRACT FROM AUTHOR]

Poplar trees use photoperiod as a precise seasonal indicator, synchronizing plant phenology with the environment. Daylength cue determines FLOWERING LOCUS T 2 (FT2) daily expression, crucial for shoot apex development and establishment of the annual growing period. However, limited evidence exists for the molecular factors controlling FT2 transcription and the conservation with the photoperiodic control of Arabidopsis flowering. We demonstrate that FT2 expression mediates growth cessation response quantitatively, and we provide a minimal data-driven model linking core clock genes to FT2 daily levels. GIGANTEA (GI) emerges as a critical inducer of the FT2 activation window, time-bound by TIMING OF CAB EXPRESSION (TOC1) and LATE ELONGATED HYPOCOTYL (LHY2) repressions. CRISPR/Cas9 loss-of-function lines validate these roles, identifying TOC1 as a long-sought FT2 repressor. Additionally, model simulations predict that FT2 downregulation upon daylength shortening results from a progressive narrowing of this activation window, driven by the phase shift observed in the preceding clock genes. This circadian-mediated mechanism enables poplar to exploit FT2 levels as an accurate daylength-meter., (© 2024. The Author(s).)

How gene activities and biomechanics together direct organ shapes is poorly understood. Plant leaf and floral organs develop from highly similar initial structures and share similar gene expression patterns, yet they gain drastically different shapes later-flat and bilateral leaf primordia and radially symmetric floral primordia, respectively. We analyzed cellular growth patterns and gene expression in young leaves and flowers of Arabidopsis thaliana and found significant differences in cell growth rates, which correlate with convergence sites of phytohormone auxin that require polar auxin transport. In leaf primordia, the PRESSED-FLOWER-expressing middle domain grows faster than adjacent adaxial domain and coincides with auxin convergence. In contrast, in floral primordia, the LEAFY-expressing domain shows accelerated growth rates and pronounced auxin convergence. This distinct cell growth dynamics between leaf and flower requires changes in levels of cell-wall pectin de-methyl-esterification and mechanical properties of the cell wall. Data-driven computer model simulations at organ and cellular levels demonstrate that growth differences are central to obtaining distinct organ shape, corroborating in planta observations. Together, our study provides a mechanistic basis for the establishment of early aerial organ symmetries through local modulation of differential growth patterns with auxin and biomechanics., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Pd-membranes are interesting in multiple ultra-pure hydrogen production processes, although they can suffer inhibition by certain species or abrasion under fluidization conditions in membrane reactors, thus requiring additional protective layers to ensure long and stable operation. The ability to incorporate intermediate and palladium films with enough adherence on both external and internal surfaces of tubular porous supports becomes crucial to minimize their complexity and cost. This study addresses the incorporation of CeO 2 and Pd films onto the internal side of PSS tubes for applications in which further protection could be required. The membranes so prepared, with a Pd-thickness around 12-15 μm, show an excellent mechanical resistance and similar performance to those prepared on the external surface. A good fit to Sieverts' law with an H 2 -permeance of 4.571 × 10 -3 mol m -2 s -1 Pa -0.5 at 400 °C, activation energy around 15.031 kJ mol -1 , and complete ideal perm-selectivity was observed. The permeate fluxes reached in H 2 mixtures with N 2 , He, or CO 2 decreased with dilution and temperature due to the inherent concentration-polarization. The presence of CO in mixtures provoked a higher decrease because of a further inhibition effect. However, the original flux was completely recovered after feeding again with pure hydrogen, maintaining stable operation for at least 1000 h.

Perennial species in the boreal and temperate regions are subject to extreme annual variations in light and temperature. They precisely adapt to seasonal changes by synchronizing cycles of growth and dormancy with external cues. Annual dormancy-growth transitions and flowering involve factors that integrate environmental and endogenous signals. MADS-box transcription factors have been extensively described in the regulation of Arabidopsis flowering. However, their participation in annual dormancy-growth transitions in trees is minimal. In this study, we investigate the function of MADS12 , a Populus tremula × alba SUPPRESSOR OF CONSTANS OVEREXPRESSION 1 ( SOC1 )-related gene. Our gene expression analysis reveals that MADS12 displays lower mRNA levels during the winter than during early spring and mid-spring. Moreover, MADS12 activation depends on the fulfillment of the chilling requirement. Hybrid poplars overexpressing MADS12 show no differences in growth cessation and bud set, while ecodormant plants display an early bud break, indicating that MADS12 overexpression promotes bud growth reactivation. Comparative expression analysis of available bud break-promoting genes reveals that MADS12 overexpression downregulates the GIBBERELLINS 2 OXIDASE 4 ( GA2ox4 ), a gene involved in gibberellin catabolism. Moreover, the mid-winter to mid-spring RNAseq profiling indicates that MADS12 and GA2ox4 show antagonistic expression during bud dormancy release. Our results support MADS12 participation in the reactivation of shoot meristem growth during ecodormancy and link MADS12 activation and GA2ox4 downregulation within the temporal events that lead to poplar bud break., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Gómez-Soto, Ramos-Sánchez, Alique, Conde, Triozzi, Perales and Allona.)

This work focused on the computational fluid dynamics (CFD) modeling of H 2 /N 2 separation in a membrane permeator module containing a supported dense Pd-based membrane that was prepared using electroless pore-plating (ELP-PP). An easy-to-implement model was developed based on a source-sink pair formulation of the species transport and continuity equations. The model also included the Darcy-Forcheimer formulation for modeling the porous stainless steel (PSS) membrane support and Sieverts' law for computing the H 2 permeation flow through the dense palladium film. Two different reactor configurations were studied, which involved varying the hydrogen flow permeation direction (in-out or out-in). A wide range of experimental data was simulated by considering the impact of the operating conditions on the H 2 separation, such as the feed pressure and the H 2 concentration in the inlet stream. Simulations of the membrane permeator device showed an excellent agreement between the predicted and experimental data (measured as permeate and retentate flows and H 2 separation). Molar fraction profiles inside the permeator device for both configurations showed that concentration polarization near the membrane surface was not a limit for the hydrogen permeation but could be useful information for membrane reactor design, as it showed the optimal length of the reactor.

Hydrogen promotion as a clean energy vector could provide an efficient strategy for realizing real decarbonization of the current energy system. Purification steps are usually required in most H 2 -production processes, providing the use of Pd-based membranes, particularly those supported on porous stainless steel (PSS), important advantages against other alternatives. In this work, new composite membranes were prepared by modifying PSS supports with graphite, as an intermediate layer, before incorporating a palladium film by electroless pore-plating. Fully dense Pd layers were reached, with an estimated thickness of around 17 μm. Permeation measurements were carried out in two different modes: H 2 permeation from the inner to the outer side of the membrane (in-out) and in the opposite way (out-in). H 2 permeances between 3.24 × 10 -4 and 4.33 × 10 -4 mol m -2 s -1 Pa -0.5 with α H2/N2 ≥ 10,000 were reached at 350-450 °C when permeating from the outer to the inner surface. Despite a general linear trend between permeating H 2 fluxes and pressures, the predicted intercept in (0,0) by the Sieverts' law was missed due to the partial Pd infiltration inside the pores. H 2 -permeances progressively decreased up to around 33% for binary H 2 -N 2 mixtures containing 40 vol% N 2 due to concentration-polarization phenomena. Finally, the good performance of these membranes was maintained after reversing the direction of the permeate flux. This fact practically demonstrates an adequate mechanical resistance despite generating tensile stress on the Pd layer during operation, which is not accomplished in other Pd membranes.

An observational study was carried out in the photodynamic therapy (PDT) section of Fuenlabrada's hospital (Madrid, Spain). Our goal was to investigate the efficacy and safety of PDT in Bowen's disease (BD). Between June 2011-June 2017 171 patients (191 lesions) with diagnosis of BD were enrolled in the study (95 women and 76 men; average age of 74.31 years). Lesions were treated with one 5-aminolaevulinic acid (BF-200 ALA)-PDT or methyl-5-aminolaevulinate (MAL)-PDT cycle of two sessions in one week. A second treatment cycle was performed in cases of clinical persistence at 12 weeks. Our results showed that 47/55 lesions were resolved (84.75%) after one or two ALA-PDT cycle and 75/136 lesions (55.15%) after one or two MAL-PDT cycles, in the 12-month follow-up. In conclusion PDT is a safe and non-invasive treatment option in BD. In addition, our results suggest a better response with ALA-PDT over MAL-PDT. Limits: observational study with a limited number of patients., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Day length is a key indicator of seasonal information that determines major patterns of behavior in plants and animals. Photoperiodism has been described in plants for about 100 years, but the underlying molecular mechanisms of day length perception and signal transduction in many systems are not well understood. In trees, photoperiod perception plays a major role in growth cessation during the autumn as well as activating the resumption of shoot growth in the spring, both processes controlled by FLOWERING LOCUS T2 (FT2) expression levels and critical for the survival of perennial plants over winter [1-4]. It has been shown that the conserved role of poplar orthologs to Arabidopsis CONSTANS (CO) directly activates FT2 expression [1, 5]. Overexpression of poplar CO is, however, not sufficient to sustain FT2 expression under short days [5], pointing to the presence of an additional short-day-dependent FT2 repression pathway in poplar. We find that night length information is transmitted via the expression level of a poplar clock gene, LATE ELONGATED HYPOCOTYL 2 (LHY2), which controls FT2 expression. Repression of FT2 is a function of the night extension and LHY2 expression level. We show that LHY2 is necessary and sufficient to activate night length repressive signaling. We propose that the photoperiodic control of shoot growth in poplar involves a balance between FT2 activating and repressing pathways. Our results show that poplar relies on night length measurement to determine photoperiodism through interaction between light signaling pathways and the circadian clock., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In the last years, hydrogen has been considered as a promising energy vector for the oncoming modification of the current energy sector, mainly based on fossil fuels. Hydrogen can be produced from water with no significant pollutant emissions but in the nearest future its production from different hydrocarbon raw materials by thermochemical processes seems to be more feasible. In any case, a mixture of gaseous compounds containing hydrogen is produced, so a further purification step is needed to purify the hydrogen up to required levels accordingly to the final application, i.e., PEM fuel cells. In this mean, membrane technology is one of the available separation options, providing an efficient solution at reasonable cost. Particularly, dense palladium-based membranes have been proposed as an ideal chance in hydrogen purification due to the nearly complete hydrogen selectivity (ideally 100%), high thermal stability and mechanical resistance. Moreover, these membranes can be used in a membrane reactor, offering the possibility to combine both the chemical reaction for hydrogen production and the purification step in a unique device. There are many papers in the literature regarding the preparation of Pd-based membranes, trying to improve the properties of these materials in terms of permeability, thermal and mechanical resistance, poisoning and cost-efficiency. In this review, the most relevant advances in the preparation of supported Pd-based membranes for hydrogen production in recent years are presented. The work is mainly focused in the incorporation of the hydrogen selective layer (palladium or palladium-based alloy) by the electroless plating, since it is one of the most promising alternatives for a real industrial application of these membranes. The information is organized in different sections including: (i) a general introduction; (ii) raw commercial and modified membrane supports; (iii) metal deposition insights by electroless-plating; (iv) trends in preparation of Pd-based alloys, and, finally; (v) some essential concluding remarks in addition to futures perspectives., Competing Interests: The authors declare no conflict of interest.