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The electrode formulation has a significant effect on the performance of lithium ion cells. The active material, binder, and conductive carbon all have different roles, and finding the optimum composition can be difficult using an iterative approach. In this study, a design of experiment (DoE) methodology is applied to the optimisation of a cathode based on lithium iron phosphate (LFP). The minimum LFP content in the electrodes is 94 wt%. Seventeen mixes are used to evaluate adhesion, resistivity, and electrochemical performance. The coating adhesion increases with binder content, and the coating conductivity increases with carbon nano-tube content. The best coatings achieve 5C:0.2C capacity ratios above 50%, despite the relatively high coat weight. Models based on just the component mixture do not replicate the discharge capacities at high rates. However, a combined mixture + process model can fit the data, and is used to predict an optimum formulation.

The size of a lithium iron phosphate (LFP) cathode mix was increased by a factor of thirty, and the capacity of the cells produced with it by a factor of three-hundred. As well as rate and cycling tests, the coatings were also characterised for adhesion and resistivity. The adhesion and total through-plane resistance were both dependent on the drying conditions during coating. The discharge capacities at high rates and the pulse resistances showed much less influence from the drying temperature. The mix formulation contained 97 wt% LFP, and was based on an earlier design of experiments (DoE) study, using relatively high active material contents. Overall, the mix exceeded the performance predicted by the modelling study.

In this report, I report in-depth studies on the various factors which affect the stability and electrochemical performance of three LiVOPO4 polymorphs. These studies are the result of collaborations between various research groups within NECCES, each contributing to the synthesis, characterization, and/or computational work. Each collaborating author is listed in the respective sections.This report consists of three main studies. In the first study, the factors affecting the stability of the three main polymorphs of LiVOPO4 (αI, β, and ε) are thoroughly studied through the use of a single precursor, LiVOPO4∙2H2O. This allows us to synthesize all three major polymorphs while limiting any differences between how they are synthesized, thus limiting any unknown factors from affecting our results. The results show that, in terms of thermodynamic stability, αI <<< β = ε. Additionally, the presence of O-vacancies stabilize ε-LiVOPO4 over β-LiVOPO4. β-LiVOPO4 is generally considered the electrochemically superior polymorph due to the favorable surfaces that form during its synthesis. This is summarized in Chapter 3.In the second part the impact of transition metal substitution in LiVOPO4 as a material for Li-ion batteries is reported. It is shown, through the use of traditional in-situ heating with XRD and a novel gradient heater technique, that Ti- and Nb-substitution cause β-LiVOPO4 to stabilize over ε-LiVOPO4 by inhibiting the formation of O-vacancies. These transition metals improve the initial capacity of β-LiVOPO4, while not affecting ε-LiVOPO4. However, both transition metals improve the cycling stability of both β- and ε-LiVOPO4, with 1% substitution resulting in the best capacity retention. These transition metals also significantly improve the rate performance of both polymorphs. This improved performance is associated to an improved Li+ ion diffusion, which is caused by a decrease in the charge-transfer resistance due to the formation of a surface coating. The work is reported in Chapter 4.In the final section the impact of Ti-, Cr-, Mn-, Zr-, Nb-, Mo-, and W-substitution on the stability of β- and ε-LiVOPO4 is reported. Ti-, Nb-, Mo-, and W-substitution are predicted to stabilize β-LiVOPO4 by increasing the overall O-vacancy formation energies. This was confirmed experimentally through the use of various post-heating experiments. On the other hand, Cr- and Mn-substitution stabilize ε-LiVOPO4 by lowering the O-vacancy formation energies. Zr-substitution is not predicted to cause any significant changes in the stability. We confirm this through the use of the as-synthesized transition-metal substituted ε-LiVOPO4. Some ideas for various avenues for further, in-depth, studies on transition-metal substituted LiVOPO4 are discussed.

In this study, three LiVOPO4 phases, α I-, β-, and ϵ-LiVOPO4, are synthesized from a single precursor, LiVOPO4-2H2O. The relative stabilities at different conditions are characterized. Specifically, αI-LiVOPO 4 is the least stable, followed by β-LiVOPO4 then ϵ-LiVOPO 4. However, the stability of β-LiVOPO4 significantly increases in an oxidizing atmosphere. The electrochemical performance of each phase is also quantified. β-LiVOPO4 has the highest capacity, followed by both ϵ- and αI-LiVOPO4, which have similar capacities. Diffusion coefficient calculations show that all (de)lithiation reactions have similar diffusion coefficients, expect for the low-voltage reactions of ϵ-LiVOPO4, which have significantly higher diffusion coefficients. Finally, we attempted to substitute V with Mo and Cr in ϵ-LiVOPO4. HEBM of LiVOPO4-2H 2O with MoO3 resulted in pure-phase ϵ-LiVOPO4 with higher capacities but faster capacity fading. Unfortunately, the data suggests that this improvement was not due to V-substitution.

Use of totally implantable venous-access ports (TIVAPs) is standard practice for patients with diseases such as solid-tumour cancers, haematological malignancies, and chronic digestive diseases. Use of TIVAPs allows long-term administration of venotoxic compounds, improves patients' quality of life, and reduces the risk of infection. Microbial contamination, formation of pathogenic biofilms, and infection, however, are associated with morbidity, mortality, and increased health-care costs. Local and systemic complications or infections related to specific pathogens might lead to device removal. Alternatively, conservative treatment with combined systemic antibiotics and antibiotic lock therapy might be useful. We discuss in-vitro and in-vivo basic and clinical research findings on the epidemiology, diagnosis, and prevention of TIVAP-related infections, the current challenges to management, promising strategies, and some treatments in development that are likely to improve outcomes of TIVAP-related infections, with a particular focus on antibiotic lock therapy.

Novel protein-coding genes can arise either from pre-existing genes or de novo ; here it is shown that functional genes emerge de novo through transitory proto-genes generated by widespread translational activity in non-genic sequences. New genes from unlikely beginnings De novo gene birth has occurred in many lineages during evolution, but how functional protein-coding genes emerge in non-functional sequences — rather than through gene rearrangement — remains unresolved. These authors observe in the yeast Saccharomyces cerevisiae that hundreds of species-specific non-genic transcripts are differentially regulated upon stress. These previously overlooked translation events seem to act as a reservoir of adaptive potential, in the form of open reading frames that occupy an evolutionary continuum ranging from non-genic sequences to genes. On the basis of their genome-wide observations, the authors suggest that de novo gene birth from the proto-gene reservoir may be more prevalent than sporadic gene duplication. Novel protein-coding genes can arise either through re-organization of pre-existing genes or de novo 1 , 2 . Processes involving re-organization of pre-existing genes, notably after gene duplication, have been extensively described 1 , 2 . In contrast, de novo gene birth remains poorly understood, mainly because translation of sequences devoid of genes, or ‘non-genic’ sequences, is expected to produce insignificant polypeptides rather than proteins with specific biological functions 1 , 3 , 4 , 5 , 6 . Here we formalize an evolutionary model according to which functional genes evolve de novo through transitory proto-genes 4 generated by widespread translational activity in non-genic sequences. Testing this model at the genome scale in Saccharomyces cerevisiae , we detect translation of hundreds of short species-specific open reading frames (ORFs) located in non-genic sequences. These translation events seem to provide adaptive potential 7 , as suggested by their differential regulation upon stress and by signatures of retention by natural selection. In line with our model, we establish that S. cerevisiae ORFs can be placed within an evolutionary continuum ranging from non-genic sequences to genes. We identify ∼1,900 candidate proto-genes among S. cerevisiae ORFs and find that de novo gene birth from such a reservoir may be more prevalent than sporadic gene duplication. Our work illustrates that evolution exploits seemingly dispensable sequences to generate adaptive functional innovation.

In a trial involving asymptomatic contacts of patients with PCR–confirmed Covid-19 in Spain, the authors compared the use of hydroxychloroquine with usual care. Postexposure therapy with hydroxychloroquine did not prevent SARS-CoV-2 infection or symptomatic Covid-19 in healthy persons.

We aimed to describe the intensity of care and its consequences on informal caregivers of stroke survivors according to the degree of care receivers' functional dependence for activities of daily living; and to identify the factors associated with caregivers' care-related quality of life. Cross-sectional analysis of prospective data collected in a cost-utility study alongside the RACECAT trial in Catalonia (Spain). One-hundred and thirty-two care receiver-caregiver pairs were interviewed six months after stroke. Functional dependence for activities of daily living was measured with the Barthel index. We assessed caregivers care-related quality of life with the CarerQoL, which measures seven dimensions of subjective burden (CarerQoL-7D) and a happiness score (CarerQoL-VAS). We evaluated the association between characteristics of informal caregivers, characteristics of care receivers, and intensity of care, and the caregiver's care-related quality of life (subjective burden and happiness) in a hypothesized model using a structural equation model. Of the 132 caregivers, 74,2% were women with an average age of 59.4 ± 12.5 years. The 56.8% of them were spouses. The care intensity ranged from a mean of 24h/week for mild to 40h/week for severe dependence. Most caregivers (76.3%) were satisfied with their task, regardless of dependence, but showed increasing problems in caring for severely dependent persons. Being a woman (coeff. -0.23; 95%CI: -0.40, -0.07), spending more time in care tasks (coeff -0.37; -0.53, -0.21) and care receiver need of constant supervision (coeff 0.31; -0.47, -0.14) were associated with higher burden of care, irrespective of the degree of dependence. Caregiver burden (coeff 0.46; 0.30-0.61) and care receiver anxiety or depression (coeff -0.19; -0.34, -0.03) were associated with lower caregiver happiness. The findings suggest the importance of developing mainly two types of support interventions for caregivers: respite and psychosocial support. Especially for women with high caring burden and/or caring for persons with high levels of anxiety or depression.

Here we explored the role of interleukin-1β (IL-1β) repressor cytokine, IL-1 receptor antagonist (IL-1rn), in both healthy and abnormal hematopoiesis. Low IL-1RN is frequent in acute myeloid leukemia (AML) patients and represents a prognostic marker of reduced survival. Treatments with IL-1RN and the IL-1β monoclonal antibody canakinumab reduce the expansion of leukemic cells, including CD34 + progenitors, in AML xenografts. In vivo deletion of IL-1rn induces hematopoietic stem cell (HSC) differentiation into the myeloid lineage and hampers B cell development via transcriptional activation of myeloid differentiation pathways dependent on NFκB. Low IL-1rn is present in an experimental model of pre-leukemic myelopoiesis, and IL-1rn deletion promotes myeloproliferation, which relies on the bone marrow hematopoietic and stromal compartments. Conversely, IL-1rn protects against pre-leukemic myelopoiesis. Our data reveal that HSC differentiation is controlled by balanced IL-1β/IL-1rn levels under steady-state, and that loss of repression of IL-1β signaling may underlie pre-leukemic lesion and AML progression. Enhanced IL-1β signaling pathway causes hematopoietic stem cell (HSC) to differentiate into myeloid cells and contributes to malignant hematopoiesis. Here the authors reveal that HSC differentiation is controlled by balanced levels of IL-1 receptor antagonist (IL-1rn) and IL-1β under steady-state, and that IL-1rn protects against pre-leukemic myelopoiesis by repressing IL-1β signaling.

Korn and colleagues report that Sirpα + dendritic cells trans-present the cytokine IL-6 to T cells through a process that requires its receptor IL-6Rα bound to dendritic cells and that trans-presentation is needed to generate pathogenic cells of the T H 17 subset of helper T cells in vivo . The cellular sources of interleukin 6 (IL-6) that are relevant for differentiation of the T H 17 subset of helper T cells remain unclear. Here we used a novel strategy for the conditional deletion of distinct IL-6-producing cell types to show that dendritic cells (DCs) positive for the signaling regulator Sirpα were essential for the generation of pathogenic T H 17 cells. Using their IL-6 receptor α-chain (IL-6Rα), Sirpα + DCs trans-presented IL-6 to T cells during the process of cognate interaction. While ambient IL-6 was sufficient to suppress the induction of expression of the transcription factor Foxp3 in T cells, trans-presentation of IL-6 by DC-bound IL-6Rα (called 'IL-6 cluster signaling' here) was needed to prevent premature induction of interferon-γ (IFN-γ) expression in T cells and to generate pathogenic T H 17 cells in vivo . Our findings should guide therapeutic approaches for the treatment of T H 17-cell-mediated autoimmune diseases.