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Donor lymphocyte infusion (DLI) results in complete cytogenetic remission (CCR) of relapsed chronic-phase chronic myeloid leukemia (CML-CP) after allogeneic stem cell transplantation (SCT) in up to 80% of patients. The main complication of DLI is graft-versus-host disease (GVHD). Decreasing the dose of DLI is associated with less GVHD but also with a longer interval between treatment and CCR. We postulated that combining α-interferon (α-IFN) with DLI would enable us to decrease the dose of DLI, thereby limiting GVHD, and at the same time to decrease the interval between DLI and CCR for patients with either a hematologic or cytogenetic relapse. For molecular relapses, we hypothesized that because of a lower tumor load, very low doses of DLI without α-IFN could be an effective treatment. Two groups of CML-CP patients treated with DLI at a very low dose of 0.5 to 1.0 × 107 mononuclear cells per kilogram, containing 2 to 6 × 106 CD3+ T cells per kilogram, were analyzed: 13 patients with a cytogenetic or a hematologic relapse after allogeneic SCT (group A) were treated with additional α-IFN therapy at a dose of 3 × 106 U 5 d/wk, and 8 patients with a molecular relapse were treated without α-IFN (group B). Twelve patients from group A reached a CCR. The median interval between DLI and CCR was 7 weeks (range, 5–18 weeks) for group A. All patients with a CCR reached complete donor chimerism at a median of 10 weeks after DLI (range, 6–121 weeks). Eleven patients reached molecular remission at a median of 15 weeks after DLI (range, 8–34 weeks). In group B, all patients reached a molecular remission at a median of 14 weeks (range, 12–29 weeks). Five patients from group A developed acute GVHD grade II to IV and extensive chronic GVHD. In group B, 1 patient developed acute GVHD grade II to IV and subsequently developed extensive chronic GVHD. With a median follow-up of 62 months, 10 patients in group A are alive and in continuous CCR. One patient had a molecular relapse, for which she successfully received additional DLI; another patient reached molecular remission only after 5 doses of DLI. Two patients from group A died of a gram-negative sepsis, and 1 died of an acute myocardial infection. In group B, all patients are alive and in molecular remission with a median follow-up of 20 months. One patient’s disease progressed but was successfully treated with DLI plus α-IFN. In conclusion, very-low-dose DLI in combination with α-IFN as treatment for cytogenetic or hematologic relapses of CML-CP after allogeneic SCT reduced the interval to obtain a CCR with acceptable GVHD when compared with the literature. Patients with a CCR also reached complete donor chimerism and complete molecular remissions. For patients with a molecular relapse, very-low-dose DLI alone is sufficient to induce molecular remissions in most patients and is associated with limited GVHD. [Copyright &y& Elsevier]

[Display omitted] • Stoichiometric model combines kinetics of pozzolanic metakaolin reactions with long-term transformation processes. • Primary pozzolanic metakaolin reactions are divided into C 4 AH 13 and C 2 ASH 8 contributions. • Activation energy for the main (C 2 ASH 8) pozzolanic metakaolin reaction is determined as 84 kJ/mol. • KOH accelerates reaction processes and reduces the activation energy of the pozzolanic metakaolin reaction to 69 kJ/mol. In the pursue of environmentally-friendly binders for the construction industry, metakaolin (MK) has emerged as promising material, with its hardening performance primarily driven by pozzolanic reactions. However, in systems containing MK and calcium hydroxide (CH), transformation reactions from metastable to stable phases, particularly in excessive CH conditions, can adversely affect material properties. To anticipate these processes, this study introduces a stoichiometry-based reaction modeling approach for pozzolanic MK reactions, encompassing both short-term kinetics and long-term transformation processes. The primary pozzolanic reactions of MK are briefly outlined, highlighting two sequential, partially overlapping reactions forming C 4 AH 13 and C 2 ASH 8. Short-term reaction kinetics are modeled using isothermal calorimetry measurements and deconvoluting the two reaction peaks. The model is in good agreement with experimental quantitative X–ray diffraction (qXRD), thermogravimetric analysis (TGA) and helium pycnometer (density, i.e. solid volume) results. Model limitations are discussed based on qualitative scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) analysis. Leveraging the proposed model, the temperature dependency of pozzolanic MK reactions is analyzed, revealing an activation energy for the primary reaction of 84 kJ/mol. The model is intended to lay a foundation for designing innovative binder systems based on metakaolin, while paving the way for sustainable construction in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oxide composition designated as metakaolin to calcium hydroxide ratio determines C-A-S-H composition and time dependent (trans)formation reactions. • Stratlingite destabilizes in the presence of calcium hydroxide and transforms to more stable hydrogarnet phases. • Sulfate addition leads to rapid ettringite formation, that may transform to monosulfoaluminate and later to hydrogarnet. • Carbonates stabilize ettringite and favor formation of carboaluminates, which may decompose at later curing ages. • Enhanced pozzolanic metakaolin reactivity modeling for low-carbon binder design requires improved understanding of structure-related dissolution kinetics. Metakaolin (MK) has emerged as a highly promising supplementary material in low carbon binders for the construction industry. In wide range of applications, from lime to cement–based materials, its hardening performance relies on the pozzolanic reactivity between MK and calcium hydroxide (CH), resulting in the formation of diverse calcium-aluminate/silicate hydrates. The reaction sequence is affected by specific conditions dictated by the binder system employed in various applications. To advance the design of binders that reduce the carbon emissions, a systematical review on MK-based reactions is crucial. This review encompasses a broad range of MK/CH ratios and examines the effect of alkali hydroxides, carbonates and sulfates. The focus is on the formation and stability of pozzolanic hydrate phases over time and under different curing temperatures. Additionally, the review addresses the characteristics that directly affect MK reactivity, such as the (calcined) clay structure and the dissolution of the reactants. The systematic findings shed light on the hydrate phase assemblage, enabling a better understanding of the reaction mechanisms in complex systems, like MK cementitious blends. The results of this review serve as a valuable foundation for the development of novel "low-carbon" binder designs and compositions for both cementitious and lime-based binders. [ABSTRACT FROM AUTHOR]

This study investigates the effects of carbon nanomaterials (CN), specifically nanohorns (CNHs) and nanotubes (MWCNTs), on geopolymer carbon nanocomposites (GCN). The research investigates 0.2%, 0.5% and 1.0% of CN and two curing conditions to understand their impact on the microstructure, morphology, and performance of GCN. Analytical techniques such as MIP, TGA-DTA, FTIR, Raman, SEM, and EDX are utilized to analyze the nanoadditives in alkali-silicate suspensions, fresh and hardened GCN. Ultrasonication is important for achieving better dispersion of MWCNTs, while CNH disperses more easily. Both MWCNTs and CNHs enhance flexural strength by up to around 58% and 44%, respectively, and reduce crack formation compared to the pristine geopolymer. Hydrothermal curing, despite leading to higher porosity, improves flexural strength due to increased geopolymerisation. The formation of a cross-polymerized network with oxo bonds and the release of water during the process contribute to increased strength and porosity, respectively. • Exploring carbon nanohorns (CNH) and multi-walled carbon nanotubes (MWCNT) as additives in geopolymers. • Highest flexural strength achieved with 0.5% MWCNTs at 60 °C curing. • Curing at 60 °C (vs. 20 °C) enhances the geopolymer network reticulation and CN-matrix interface. • Hydrothermal curing at 60 °C (vs. 20 °C) increases porosity but improves flexural strength. • Improvements through enhanced geopolymerisation and reduced bound water content. [ABSTRACT FROM AUTHOR]

Technologies based on phase change materials (PCMs) are promising solutions to reduce energy consumption in buildings and related greenhouse gas emissions. However, the performance of passive PCMs in buildings is highly dependent on the melting temperatures employed, as well as the climate where the building is located. Therefore, the present contribution describes an optimization-based method to design passive latent energy storage in buildings by using PCMs with different melting temperatures. To achieve this goal, a multi-objective genetic algorithm is coupled with the building energy models developed in EnergyPlus to find the best trade-off between annual heating and cooling loads. A small office is chosen as a case study to evaluate the energy performance of the buildings incorporating the proposed PCM approach. Three different PCM layers are added to the ceilings and the external and internal walls of the building, and their parametric models are developed in EnergyPlus to optimize the melting temperature and thickness of each PCM layer simultaneously. Moreover, a method to select climate-representative locations according to the ASHRAE 169-2020 climate classification and within the WMO Region VI (Europe) is proposed and applied, resulting in eight well-representative locations. An optimization-based design is carried out for each selected location and the performances of the optimized building designs are systematically compared to the ones of the baseline models. The optimization results achieved show that regardless of the climate zone analyzed, using several PCMs with different melting temperatures instead of a single one, is preferred. Moreover, the best performance of PCMs is attained in climate zones where both the heating and cooling loads are present. Thus, the highest saving regarding the annual total loads of 11.7% is achieved in zone 5A (Cold), while the lowest one of 2.3% is obtained in zone 1B (Very hot). [Display omitted] • Using PCMs with different melting temperatures in buildings is proposed. • A multi-objective optimization method to design the PCMs' properties is introduced. • Eight climate-representative locations in the WMO Region VI (Europe) are selected. • PCMs with different melting temperatures instead of a single one is preferred. • The best performance of PCMs is attained in climates where both loads are present. [ABSTRACT FROM AUTHOR]

Subunit D of multisubunit RNA polymerase from many species of archaea is predicted to bind one to two iron-sulfur (Fe-S) clusters, the function of which is unknown. A survey of encoded subunit D in the genomes of sequenced archaea revealed six distinct groups based on the number of complete or partial [4Fe- 4S] cluster motifs within domain 3. Only subunitDfrom strictly anaerobic archaea, including all members of the Methanosarcinales, are predicted to bind two [4Fe-4S] clusters. We report herein the purification and characterization of Methanosarcina acetivorans subunit D in complex with subunit L. Expression of subunit D and subunit L in Escherichia coli resulted in the purification of a D-L heterodimer with only partial [4Fe-4S] cluster content. Reconstitution in vitro with iron and sulfide revealed that the M. acetivorans D-L heterodimer is capable of binding two redox-active [4Fe-4S] clusters. M. acetivorans subunit D deleted of domain 3 (DΔD3) was still capable of co-purifying with subunit L but was devoid of [4Fe-4S] clusters. Affinity purification of subunit D or subunit DΔD3 from M. acetivorans resulted in the co-purification of endogenous subunit L with each tagged subunit D. Overall, these results suggest that domain 3 of subunit D is required for [4Fe-4S] cluster binding, but the [4Fe-4S] clusters and domain 3 are not required for the formation of the D-L heterodimer. However, exposure of two [4Fe-4S] cluster-containing D-L heterodimer to oxygen resulted in loss of the [4Fe-4S] clusters and subsequent protein aggregation, indicating that the [4Fe-4S] clusters influence the stability of the D-L heterodimer and therefore have the potential to regulate the assembly and/or activity of RNA polymerase in an oxidant- dependent manner. [ABSTRACT FROM AUTHOR]