Effect of phase separation and supercooling on the storage capacity in a commercial latent heat thermal energy storage: Experimental cycling of a salt hydrate PCM

Latent heat storage technologies offer process benefits like daily peak shaving. In this work a commercial storage design for storing cold thermal energy has been studied using a laboratory prototype containing 168 kg of a commercial salt-hydrate phase change material (PCM). The storage was charged and discharged with subsequent cycles at different mass flow rates over a fixed temperature range and duration. It was found that the PCM TES design exhibits phase separation and increased supercooling with continuous cycling. Both phenomena lead to a gradual decrease of the effective storage capacity. With later cycles only the bottom part stores latent heat, while the top and middle parts of the storage remain liquid. The results were repeatable and are consistent with T-History measurements of samples from the PCM TES before and after cycling. It is likely that the PCM itself does not suffer from incongruent melting. Instead, the phase separation is likely to occur due to a segregation of different liquid phases across the height of the storage. It was found that T-History measurements alone are not able to predict this behavior. Moreover, it is shown that phase separation in the storage can be reversed by increasing the PCM temperature and mechanical mixing of the liquid phase. This phase separation has to be prevented in future work in order to achieve stable performance with the studied storage design

Mn-Doped Glass–Ceramic Bioactive (Mn-BG) Thin Film to Selectively Enhance the Bioactivity of Electrospun Fibrous Polymeric Scaffolds

In recent years, significant progress has been made in the development of new technologies to meet the demand for engineered interfaces with appropriate properties for osteochondral unit repair and regeneration. In this context, we combined two methodologies that have emerged as powerful approaches for tissue engineering application: electrospinning to fabricate a nanofibrous polymeric scaffold and pulsed laser deposition to tune and control the composition and morphology of the scaffold surface. A multi-component scaffold composed of synthetic and natural polymers was proposed to combine the biocompatibility and suitable mechanical properties of poly(D,L-lactic acid) with the hydrophilicity and cellular affinity of gelatin. As part of a biomimetic strategy for the generation of bi-functional scaffolds, we coated the electrospun fibers with a thin film of a bioactive glass–ceramic material supplemented with manganese ions. The physico-chemical properties and composition of the bi-layered scaffold were investigated, and its bioactivity, in terms of induced mineralization, was tested by incubation in a simulated body fluid buffer. The processes of the inorganic film dissolution and the calcium phosphate phases growth were followed by microscopic and spectroscopic techniques, confirming that a combination of bioactive glass–ceramics and nanofibrous scaffolds has promising potential in the regeneration of osteochondral tissue due to its ability to induce mineralization in connective tissues. © 2022 by the authors

Preferential patterns of myocardial iron deposit by multislice multiecho T2* CMR in thalassemia major patients

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Compartmentalization of integrin α6β4 signaling in lipid rafts

Integrin α6β4 signaling proceeds through Src family kinase (SFK)–mediated phosphorylation of the cytoplasmic tail of β4, recruitment of Shc, and activation of Ras and phosphoinositide-3 kinase. Upon cessation of signaling, α6β4 mediates assembly of hemidesmosomes. Here, we report that part of α6β4 is incorporated in lipid rafts. Metabolic labeling in combination with mutagenesis indicates that one or more cysteine in the membrane-proximal segment of β4 tail is palmitoylated. Mutation of these cysteines suppresses incorporation of α6β4 in lipid rafts, but does not affect α6β4-mediated adhesion or assembly of hemidesmosomes. The fraction of α6β4 localized to rafts associates with a palmitoylated SFK, whereas the remainder does not. Ligation of palmitoylation-defective α6β4 does not activate SFK signaling to extracellular signal–regulated kinase and fails to promote keratinocyte proliferation in response to EGF. Thus, compartmentalization in lipid rafts is necessary to couple the α6β4 integrin to a palmitoylated SFK and promote EGF-dependent mitogenesis

Concomitant Administration of Capecitabine and Folate Supplements: Need to Encourage Medication Reconciliation

Hand-Foot syndrome (HFS) and diarrhoea are dose-limiting Adverse Drug Reactions (ADRs) of capecitabine-based chemotherapy. Four polymorphisms in the dihydropyrimidine dehydrogenase (DPYD) gene, encoding the DPD enzyme responsible for the metabolism of fluoropyrimidines, such as capecitabine, are strongly associated with severe ADRs, and their screening should be performed before starting treatment. Moreover, capecitabine-related toxicity may worsen due to drug-drug and drug-supplement interactions. Here we investigated factors responsible for severe HFS and diarrhoea presented by two patients, non-carriers of the recommended DPYD single nucleotide polymorphisms (SNPs) but carriers of other genetic variants suggested to increase the risk of capecitabine-related ADRs. Through careful therapy recognition, we demonstrated that, unbeknownst to the oncologists, the patients were taking folic acid during the treatment with capecitabine at a dosage higher than 2000 mg/m(2), which is the maximum tolerated dose when folate is administered. To resolve the ADRs, the therapy had to be drastically changed. In one case, dose reduction of capecitabine and discontinuation of lipid-lowering agents were carried out. In the other case, discontinuation of capecitabine and folic acid and capecitabine re-administration were performed after a month. Genetic and environmental factors should be considered good predictors of severe capecitabine-related toxicity. Medication reconciliation should be encouraged to avoid the harmful consequences of inappropriate treatments

Inhibition of exosome biogenesis affects cell motility in heterogeneous sub-populations of paediatric-type diffuse high-grade gliomas

Background: Paediatric-type diffuse High-Grade Gliomas (PDHGG) are highly heterogeneous tumours which include distinct cell sub-populations co-existing within the same tumour mass. We have previously shown that primary patient-derived and optical barcoded single-cell-derived clones function as interconnected networks. Here, we investigated the role of exosomes as a route for inter-clonal communication mediating PDHGG migration and invasion. Results: A comprehensive characterisation of seven optical barcoded single-cell-derived clones obtained from two patient-derived cell lines was performed. These analyses highlighted extensive intra-tumour heterogeneity in terms of genetic and transcriptional profiles between clones as well as marked phenotypic differences including distinctive motility patterns. Live single-cell tracking analysis of 3D migration and invasion assays showed that the single-cell-derived clones display a higher speed and longer travelled distance when in co-culture compared to mono-culture conditions. To determine the role of exosomes in PDHGG inter-clonal cross-talks, we isolated exosomes released by different clones and characterised them in terms of marker expression, size and concentration. We demonstrated that exosomes are actively internalized by the cells and that the inhibition of their biogenesis, using the phospholipase inhibitor GW4689, significantly reduced the cell motility in mono-culture and more prominently when the cells from the clones were in co-culture. Analysis of the exosomal miRNAs, performed with a miRNome PCR panel, identified clone-specific miRNAs and a set of miRNA target genes involved in the regulation of cell motility/invasion/migration. These genes were found differentially expressed in co-culture versus mono-culture conditions and their expression levels were significantly modulated upon inhibition of exosome biogenesis. Conclusions: In conclusion, our study highlights for the first time a key role for exosomes in the inter-clonal communication in PDHGG and suggests that interfering with the exosome biogenesis pathway may be a valuable strategy to inhibit cell motility and dissemination for these specific diseases

Characterizing phase change materials using the T-History method: On the factors influencing the accuracy and precision of the enthalpy-temperature curve

While research on using the latent heat of so called phase change materials (PCMs) for thermal energy storage has gained increasing interest in the last decade, the measurement of its thermal properties are still subject to research. The T-History method has been frequently used by researchers to measure the enthalpy–temperature curve of PCMs but the factors influencing its accuracy and precision have rarely been discussed. This work provides a systematic experimental study of an organic PCM based on different insulated sample holders. It is first shown that the data evaluation method has to be adjusted against noise to improve both accuracy and precision for all experimental setups. The results moreover show that neglecting the insulation thermal mass in the experimental setup leads to systematic errors in the enthalpy results due to oversimplification of the mathematical model. This confirms a previous numerical study by the authors. It is recommended that either the mathematical model or the experimental setup are adjusted in future work to decrease this error. Until then it is generally recommended to use sample holders with a high ratio between the thermal mass of the PCM to the insulated sample holder. This is further supported by a measurement uncertainty analysis via Monte Carlo simulations