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Progress toward durable and energy-dense lithium-ion batteries has been hindered by instabilities at electrolyte–electrode interfaces, leading to poor cycling stability, and by safety concerns associated with energy-dense lithium metal anodes. Solid polymeric electrolytes (SPEs) can help mitigate these issues; however, the SPE conductivity is limited by sluggish polymer segmental dynamics. We overcome this limitation via zwitterionic SPEs that self-assemble into superionically conductive domains, permitting decoupling of ion motion and polymer segmental rearrangement. Although crystalline domains are conventionally detrimental to ion conduction in SPEs, we demonstrate that semicrystalline polymer electrolytes with labile ion–ion interactions and tailored ion sizes exhibit excellent lithium conductivity (1.6 mS/cm) and selectivity (t + ≈ 0.6–0.8). This new design paradigm for SPEs allows for simultaneous optimization of previously orthogonal properties, including conductivity, Li selectivity, mechanics, and processability.

Solid-state Li–S batteries (SSLSBs) are made of low-cost and abundant materials free of supply chain concerns. Owing to their high theoretical energy densities, they are highly desirable for electric vehicles 1 – 3 . However, the development of SSLSBs has been historically plagued by the insulating nature of sulfur 4 , 5 and the poor interfacial contacts induced by its large volume change during cycling 6 , 7 , impeding charge transfer among different solid components. Here we report an S 9.3 I molecular crystal with I 2 inserted in the crystalline sulfur structure, which shows a semiconductor-level electrical conductivity (approximately 5.9 × 10 −7  S cm −1 ) at 25 °C; an 11-order-of-magnitude increase over sulfur itself. Iodine introduces new states into the band gap of sulfur and promotes the formation of reactive polysulfides during electrochemical cycling. Further, the material features a low melting point of around 65 °C, which enables repairing of damaged interfaces due to cycling by periodical remelting of the cathode material. As a result, an Li–S 9.3 I battery demonstrates 400 stable cycles with a specific capacity retention of 87%. The design of this conductive, low-melting-point sulfur iodide material represents a substantial advancement in the chemistry of sulfur materials, and opens the door to the practical realization of SSLSBs. A conductive, low-melting-point and healable sulfur iodide material aids the practical realization of solid-state Li–S batteries, which have high theoretical energy densities and show potential in next-generation battery chemistry.

High energy density batteries are essential for compact and lightweight power storage, enabling longer lasting and more efficient portable electronic devices, electric vehicles, and grid storage solutions. Advancements in battery technology to enhance energy storage capacity and extend range are crucial for the complete transition to renewable energy. Currently, the capacity of state-of-the-art batteries is limited by the cathode and improvements in their design are contingent on better understanding of their working mechanisms. This dissertation investigates the layered lithium transition metal oxide class of cathodes, with a focus on Co-free compositions (LiNi0.5Mn0.5O2 and LiNiO2), and explores the relationship between cathode composition, structure, and performance.We first develop advanced characterization techniques that probe the electron spins in cathodes to investigate reaction mechanisms occurring during battery operation. Operando cells for magnetometry and electron paramagnetic resonance (EPR) were designed and tested. These electron spin probes provide complementary insights, which aid in interpretation of ambiguous data. We demonstrate the tandem use of these cells on LiNi0.5Mn0.5O2 and show that the magnetism and redox reactions in the charge cycle are largely influenced by the Ni/Li antisite defects in the material. Similarly, in LiNiO2 the defects in the as-synthesized material are found to have a significant contribution to its irreversible capacity. Twin boundaries and Ni over-stoichiometry (y in Li1-yNi1+yO2) are quantified through X-ray diffraction, magnetometry, and solid-state nuclear magnetic resonance (NMR) assisted with first-principles calculation of ssNMR parameters. These planar and point defects prevent lithium reinsertion at low voltages in the initial cycle due to impeded lithium diffusion. Finally, the electrochemical aging mechanism in LiNiO2 is investigated. Structural changes in LiNiO2 induced by extended high voltage cycling are correlated with diminishing capacity retention. The capacity decay is attributed to Li inventory loss and interlayer Ni-migration. The methodology and defect-property relationships established here will aid in future design of improved batteries.

Solid-state Li-S batteries (SSLSBs) are made of low-cost and abundant materials free of supply chain concerns. Owing to their high theoretical energy densities, they are highly desirable for electric vehicles. However, the development of SSLSBs has been historically plagued by the insulating nature of sulfur and the poor interfacial contacts induced by its large volume change during cycling, impeding charge transfer among different solid components. Here we report an S9.3I molecular crystal with I2 inserted in the crystalline sulfur structure, which shows a semiconductor-level electrical conductivity (approximately 5.9 × 10-7 S cm-1) at 25 °C; an 11-order-of-magnitude increase over sulfur itself. Iodine introduces new states into the band gap of sulfur and promotes the formation of reactive polysulfides during electrochemical cycling. Further, the material features a low melting point of around 65 °C, which enables repairing of damaged interfaces due to cycling by periodical remelting of the cathode material. As a result, an Li-S9.3I battery demonstrates 400 stable cycles with a specific capacity retention of 87%. The design of this conductive, low-melting-point sulfur iodide material represents a substantial advancement in the chemistry of sulfur materials, and opens the door to the practical realization of SSLSBs.

Operando electron spin probes, namely magnetometry and electron paramagnetic resonance (EPR), provide real-time insights into the electrochemical processes occurring in battery materials and devices. In this work, we describe the design criteria and outline the development of operando magnetometry and EPR electrochemical cells. Notably, we show that a clamping mechanism, or springs, are needed to achieve sufficient compression of the battery stack and an electrochemical performance on par with that of a standard Swagelok-type cell. The tandem use of operando EPR and magnetometry allows us to identify five distinct and reversible redox processes taking place on charge and discharge of the intercalation-type LiNi0.5Mn0.5O2 Li-ion cathode. While redox processes in conversion-type electrodes are notoriously difficult to investigate using standard characterization methods (e.g. X-ray based) and/or post mortem analysis, due to the formation of poorly crystalline and metastable reaction intermediates and products during cycling, we show that operando magnetometry provides unique insight into the kinetics and reversibility of Fe nanoparticle formation in the Na3FeF6 electrode for Na-based batteries. Step increases in the cell magnetization upon extended cycling indicate the build-up of Fe nanoparticles in the system, hinting at only partially reversible charge-discharge processes. The broad applicability of the tools developed herein to a range of electrode chemistries and structures, from intercalation to conversion electrodes, and from crystalline to amorphous systems, makes them particularly promising for the development of electrochemical energy storage technologies and beyond.

The global burden of pediatric severe respiratory illness is substantial, and influenza viruses contribute to this burden. Systematic surveillance and testing for influenza among hospitalized children has expanded globally over the past decade. However, only a fraction of the data has been used to estimate influenza burden. In this analysis, we use surveillance data to provide an estimate of influenza-associated hospitalizations among children worldwide. We aggregated data from a systematic review (n = 108) and surveillance platforms (n = 37) to calculate a pooled estimate of the proportion of samples collected from children hospitalized with respiratory illnesses and positive for influenza by age group (<6 mo, <1 y, <2 y, <5 y, 5-17 y, and <18 y). We applied this proportion to global estimates of acute lower respiratory infection hospitalizations among children aged <1 y and <5 y, to obtain the number and per capita rate of influenza-associated hospitalizations by geographic region and socio-economic status. Influenza was associated with 10% (95% CI 8%-11%) of respiratory hospitalizations in children <18 y worldwide, ranging from 5% (95% CI 3%-7%) among children <6 mo to 16% (95% CI 14%-20%) among children 5-17 y. On average, we estimated that influenza results in approximately 374,000 (95% CI 264,000 to 539,000) hospitalizations in children <1 y-of which 228,000 (95% CI 150,000 to 344,000) occur in children <6 mo-and 870,000 (95% CI 610,000 to 1,237,000) hospitalizations in children <5 y annually. Influenza-associated hospitalization rates were more than three times higher in developing countries than in industrialized countries (150/100,000 children/year versus 48/100,000). However, differences in hospitalization practices between settings are an important limitation in interpreting these findings. Influenza is an important contributor to respiratory hospitalizations among young children worldwide. Increasing influenza vaccination coverage among young children and pregnant women could reduce this burden and protect infants <6 mo.

The frontotemporal dementia (FTD) spectrum is a heterogeneous group of neurodegenerative syndromes with overlapping clinical, molecular and pathological features, all of which challenge the design of clinical trials in these conditions. To date, no pharmacological interventions have been proven effective in significantly modifying the course of these disorders. This study critically reviews the construct and methodology of previously published randomised controlled trials (RCTs) in FTD spectrum disorders in order to identify limitations and potential reasons for negative results. Moreover, recommendations based on the identified gaps are elaborated in order to guide future clinical trial design. A systematic literature review was carried out and presented in conformity with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. A total of 23 RCTs in cohorts with diagnoses of behavioural and language variants of FTD, corticobasal syndrome and progressive supranuclear palsy syndrome were identified out of the 943 citations retrieved and were included in the qualitative review. Most studies identified were early-phase clinical trials that were small in size, short in duration and frequently underpowered. Diagnoses of populations enrolled in clinical trials were based on clinical presentation and rarely included precision-medicine tools, such as genetic and molecular testing. Uniformity and standardisation of research outcomes in the FTD spectrum are essential. Several elements should be carefully considered and planned in future clinical trials. We anticipate that precision-medicine approaches will be crucial to adequately address heterogeneity in the FTD spectrum research.

As Vietnam navigates challenges to its animal, human, and environmental health (One Health) during rapid economic transitions, understanding local perceptions of sustainable food systems, particularly aquatic foods, is vital. This study employs a transdisciplinary, autoethnographic approach to exploring the cultural significance of aquatic food perceptions within Vietnamese communities. Data were primarily sourced through an autoethnographic triangulation method, involving detailed field diaries, vignettes, and interactive workshop data collected from local stakeholders. Our distinctive approach, involving researchers from environmental science, computer science, linguistics, political ecology, aquaculture, nutrition, human physiology, marketing, and accounting and accountability, as both participants and observers, illuminates the lived experiences that shape food perceptions within Vietnam’s specific food agro-ecosystems. By embedding aquatic food perceptions within the One Health framework, we identify key intersections between human, animal, and environmental health. Through cross-disciplinary narrative analysis, our study uncovers the social, political, economic, cultural, and linguistic dimensions surrounding aquatic food perceptions at local, regional, and national levels in Vietnam. Our study highlights the unique contribution of qualitative methods to addressing questions that hard data cannot answer in understanding perceptions of aquatic foods. The study emphasizes the need for an integrated, culturally informed, and transdisciplinary approach to addressing the complex factors influencing One Health outcomes in Vietnam. This research contributes to the broader discourse on sustainable food practices and One Health initiatives, proposing culturally informed interventions aimed at enhancing ecological resilience and public health.

SH2D1A , which encodes signaling lymphocyte activation molecule (SLAM)–associated protein (SAP), is altered in patients with X-linked lymphoproliferative disease (XLP), a primary immunodeficiency. SAP-deficient mice infected with lymphocytic choriomeningitis virus had greatly increased numbers of CD8 + and CD4 + interferon-γ–producing spleen and liver cells compared to wild-type mice. The immune responses of SAP-deficient mice to infection with Leishmania major together with in vitro studies showed that activated SAP-deficient T cells had an impaired ability to differentiate into T helper 2 cells. The aberrant immune responses in SAP-deficient mice show that SAP controls several distinct key T cell signal transduction pathways, which explains in part the complexity of the XLP phenotypes.

SH2D1A, which encodes signaling lymphocyte activation molecule (SLAM)-associated protein (SAP), is altered in patients with X-linked lymphoproliferative disease (XLP), a primary immunodeficiency. SAP-deficient mice infected with lymphocytic choriomeningitis virus had greatly increased numbers of CD8 super(+) and CD4 super(+) interferon- gamma -producing spleen and liver cells compared to wild-type mice. The immune responses of SAP-deficient mice to infection with Leishmania major together with in vitro studies showed that activated SAP-deficient T cells had an impaired ability to differentiate into T helper 2 cells. The aberrant immune responses in SAP-deficient mice show that SAP controls several distinct key T cell signal transduction pathways, which explains in part the complexity of the XLP phenotypes.