Azide-Substituted 1,2,3-Triazolium Salts as Useful Synthetic Synthons: Access to Triazenyl Radicals and Staudinger Type Reactivity.

Mesoionic carbenes (MIC) are a popular class of compound that are heavily investigated at the moment. The access to cationic MICs, and the ability of MICs to stabilize radicals are two highly attractive fields that have hardly been explored until now. Here the synthesis and characterisation of three different cationic azide-substituted 1,2,3-triazolium salts, used as building blocks for studying their reactivity towards triphenylphosphine are reported, where the reactivity is dependent on the nature of the starting triazolium salt. Furthermore, the cationic triazolium salts were used to develop a series of unsymmetrical MIC-triazene-NHC/MIC' compounds, which can be readily converted to the radical form either by electrochemical or chemical methods. These radicals, which display NIR electrochromism, were investigated using a battery of techniques such as electrochemistry, UV/Vis/NIR and EPR spectroelectrochemistry, and theoretical calculations. Interestingly, the MIC plays an important role in the stabilization of the triazenyl radical, particularly in a competitive role vis-à-vis their NHC counterparts. These results shed new light on the ability of MICs to stabilize radicals, and possibly also on their π-accepting ability.

Ruthenium Complexes of Polyfluorocarbon Substituted Terpyridine and Mesoionic Carbene Ligands: An Interplay in CO2 Reduction.

In recent years terpyridines (tpy) and mesoionic carbenes (MIC) have been widely used in metal complexes. With the right combination with a metal center, both of these ligands are individually known to generate excellent catalysts for CO2 reduction. In this study, we combine the potentials of PFC (PFC=polyfluorocarbon) substituted tpy and MIC ligands within the same platform to obtain a new class of complexes, which we investigated with respect to their structural, electrochemical and UV/Vis/NIR spectroelectrochemical properties. We further show that the resulting metal complexes are potent electrocatalysts for CO2 reduction in which CO is exclusively formed with a faradaic efficiency of 92 %. A preliminary mechanistic study, including the isolation and characterization of a key intermediate is also reported.

Spin State in Homoleptic Iron(II) Terpyridine Complexes Influences Mixed Valency and Electrocatalytic CO2 Reduction.

Two homoleptic Fe(II) complexes in different spin states bearing superbasic terpyridine derivatives as ligands are investigated to determine the relationship between spin state and electrochemical/spectroscopic behavior. Antiferromagnetic coupling between a ligand-centered radical and the high-spin metal center leads to an anodic shift of the first reduction potential and results in a species that shows mixed valency with a moderately intense intervalence-charge-transfer band. The differences afforded by the different spin states extend to the electrochemical reactivity of the complexes: while the low-spin species is a precatalyst for electrocatalytic CO2 reduction and leads to the preferential formation of CO with a Faradaic efficiency of 37%, the high-spin species only catalyzes proton reduction at a modest Faradaic efficiency of approximately 20%.

Risky business: COVAX and the financialization of global vaccine equity.

BACKGROUND: During the first year and a half of the COVID-19 pandemic, COVAX has been the world's most prominent effort to ensure equitable access to SARS-CoV-2 vaccines. Launched as part of the Access to COVID-19 Tools Accelerator (Act-A) in June 2020, COVAX suggested to serve as a vaccine buyers' and distribution club for countries around the world. It also aimed to support the pharmaceutical industry in speeding up and broadening vaccine development. While COVAX has recently come under critique for failing to bring about global vaccine equity, influential politicians and public health advocates insist that future iterations of it will improve pandemic preparedness. So far COVAX's role in the ongoing financialization of global health, i.e. in the rise of financial concepts, motives, practices and institutions has not been analyzed. METHODS: This article describes and critically assesses COVAX's financial logics, i.e. the concepts, arguments and financing flows on which COVAX relies. It is based on a review of over 109 COVAX related reports, ten in-depth interviews with global health experts working either in or with COVAX, as well as participant observation in 18 webinars and online meetings concerned with global pandemic financing, between September 2020 and August 2021. RESULTS: The article finds that COVAX expands the scale and scope of financial instruments in global health governance, and that this is done by conflating different understandings of risk. Specifically, COVAX conflates public health risk and corporate financial risk, leading it to privilege concerns of pharmaceutical companies over those of most participating countries - especially low and lower-middle income countries (LICs and LMICs). COVAX thus drives the financialization of global health and ends up constituting a risk itself - that of perpetuating the downsides of financialization (e.g. heightened inequality, secrecy, complexity in governance, an ineffective and slow use of aid), whilst insufficiently realising its potential benefits (pandemic risk reduction, increased public access to emergency funding, indirect price control over essential goods and services). CONCLUSION: Future iterations of vaccine buyers' and distribution clubs as well as public vaccine development efforts should work towards reducing all aspects of public health risk rather than privileging its corporate financial aspects. This will include reassessing the interplay of aid and corporate subsidies in global health.

Interrogating the World Bank's role in global health knowledge production, governance, and finance.

BACKGROUND: In the nearly half century since it began lending for population projects, the World Bank has become one of the largest financiers of global health projects and programs, a powerful voice in shaping health agendas in global governance spaces, and a mass producer of evidentiary knowledge for its preferred global health interventions. How can social scientists interrogate the role of the World Bank in shaping 'global health' in the current era? MAIN BODY: As a group of historians, social scientists, and public health officials with experience studying the effects of the institution's investment in health, we identify three challenges to this research. First, a future research agenda requires recognizing that the Bank is not a monolith, but rather has distinct inter-organizational groups that have shaped investment and discourse in complicated, and sometimes contradictory, ways. Second, we must consider how its influence on health policy and investment has changed significantly over time. Third, we must analyze its modes of engagement with other institutions within the global health landscape, and with the private sector. The unique relationships between Bank entities and countries that shape health policy, and the Bank's position as a center of research, permit it to have a formative influence on health economics as applied to international development. Addressing these challenges, we propose a future research agenda for the Bank's influence on global health through three overlapping objects of and domains for study: knowledge-based (shaping health policy knowledge), governance-based (shaping health governance), and finance-based (shaping health financing). We provide a review of case studies in each of these categories to inform this research agenda. CONCLUSIONS: As the COVID-19 pandemic continues to rage, and as state and non-state actors work to build more inclusive and robust health systems around the world, it is more important than ever to consider how to best document and analyze the impacts of Bank's financial and technical investments in the Global South.

Rhenium Complexes of Pyridyl-Mesoionic Carbenes: Photochemical Properties and Electrocatalytic CO2 Reduction.

Mesoionic carbenes have found wide use as components of homogeneous catalysts. Recent discoveries have, however, shown that metal complexes of such ligands also have huge potential in photochemical research and in the activation of small molecules. We present here three ReI complexes with mesoionic pyridyl-carbene ligands. The complexes display reduction steps which were investigated via UV-vis-NIR-IR spectro-electrochemistry, and these results point toward an EC mechanism. The ReI compounds emit in the visible range in solution at room temperature with excited state lifetimes that are dependent on the substituents of the mesoionic carbenes. These complexes are also potent electrocatalysts for the selective reduction of CO2 to CO. Whereas the substituents on the carbenes have no influence on the reduction potentials, the electrocatalytic efficiency is strongly dependent on the substituents. This fact is likely a result of catalyst instability. The results presented here thus introduce mesoionic carbenes as new potent ligands for the generation of emissive ReI complexes and for electrocatalytic CO2 reduction.

Accordion-Like Motion in Electrochemically Switchable Crown Ether/Ammonium Oligorotaxanes.

Reversible oxidation reactions in electrochemically switchable oligorotaxanes with tetrathiafulvalene (TTF) decorated 24-crown-8 ether wheels generate intramolecular mixed-valence and radical-cation interactions between the wheels. This induces shuttling of the wheels and a contraction of inter-wheel distances. Further oxidation generates repulsive forces between the TTFs and maximizes the inter-wheel distances instead. These interactions and co-conformational changes were not observed for structurally similar controls in which acetyl groups along the axle prevent translational motion of the wheels. This operation mode of oligorotaxanes, which is reminiscent of an accordion-like motion, is promising for functional materials and nanodevices such as piston-type rotaxane motors.

Influence of Mesoionic Carbenes on Electro- and Photoactive Ru and Os Complexes: A Combined (Spectro-)Electrochemical, Photochemical, and Computational Study.

In recent years, mesoionic carbenes (MICs) are finding increasing use as building blocks of electro- and photoactive metal complexes. We present here a series of RuII and OsII polypyridine complexes where one or two pyridyl moieties of the well-known tris(bipyridine) analogues are replaced by MICs. We probe the structural, electrochemical, UV-vis-NIR/electron paramagnetic resonance spectroelectrochemical, and photophysical properties of these complexes as a function of the number of MICs in them. Insights from theoretical studies are used to describe the electronic structures of the various redox states. Additionally, electron flux density calculations provide an idea of the flow of electron densities in the excited states of these molecules. This is the first time that such electron flux density calculations are used to probe the excited state properties of transition metal complexes. Our results conclusively prove that the incorporation of MICs into Ru/Os-polypyridyl complexes has a profound influence on the ground and the excited state redox potentials, the position of the emission bands, as well as on the lifetimes of the excited states. These observations might thus be useful for the generation of novel photocatalysts and photosensitizers for dye-sensitized-solar-cells based on MICs.

COVAX and the rise of the 'super public private partnership' for global health.

COVAX, the vaccines pillar of the Access to Covid-19 Tools Accelerator (ACT-A), has been promoted as 'the only global solution' to vaccine equity and ending the Covid-19 pandemic. ACT-A and COVAX build on the public-private partnership (PPP) model that dominates global health governance, but take it to a new level, constituting an experimental form that we call the 'super-PPP'. Based on an analysis of COVAX's governance structure and its difficulties in achieving its aims, we identify several features of the super-PPP model. First, it aims to coordinate the fragmented global health field by bringing together existing PPPs in an extraordinarily complex Russian Matryoshka doll-like structure. Second, it attempts to scale up a governance model designed for donor-dependent countries to tackle a health crisis affecting the entire world, pitting it against the self-interest of its wealthiest government partners. Third, the super-PPP's structural complexity obscures the vast differences between constituent partners, giving pharmaceutical corporations substantial power and making public representation, transparency, and accountability elusive. As a super-PPP, COVAX reproduces and amplifies challenges associated with the established PPPs it incorporates. COVAX's limited success has sparked a crisis of legitimacy for the voluntary, charity-based partnership model in global health, raising questions about its future.

Formation of magnetic aluminium oxyhydroxide nanorods and use for hyperthermal effects.

In the present work, we show that a porous alumina template can easily be filled with magnetic nanoparticles and then be sealed by a hot water treatment (by forming an aluminium oxyhydroxide (AlOOH) sealant layer). The porous layer then can be separated from the substrate by an etch to form free magnetic AlOOH nano-capsules. The process allows for a straightforward and highly defined size control of the magnetic units and can easily be scaled up. Furthermore, as AlOOH is biocompatible and has been used as a drug adjuvant for human use, the nanorod shaped capsules are highly promising for biomedical applications such as hyperthermal effects (heating in alternating magnetic fields).

Trisubstituted geminal diazaalkene derived transient 1,2-carbodications.

The coulombic repulsion between two adjacent cation centres of 1,2-carbodications is known to decrease with π- and/or n-donor substituents by a positive charge delocalization. Here we report the delocalization of the positive charge of transient 1,2-carbodications having one H-substituent by an intramolecular base-coordination. N-heterocyclic olefin (NHO) derived 2-pyrrolidinyl appended trisubstituted geminal diazaalkenes were used for the generation of transient 1,2-carbodications through a 2-e chemical oxidation process. We have also studied the 1-e oxidation reaction of trisubstituted geminal diazaalkenes (electrochemically and chemically) and also studied them using in situ EPR spectroscopy.

Amphiphilic TiO2 nanotube arrays: an actively controllable drug delivery system.

Amphiphilic TiO(2) nanotube arrays are fabricated by a two-step anodization procedure combined with hydrophobic monolayer modification after the first step. These tubes can be used as biomolecular carriers, where the outer hydrophobic barrier provides an efficient cap against drug leaching to the environment. By utilizing the photocatalytic ability of TiO(2), a precisely controlled removal of the cap and a highly controlled release of the hydrophilic payload (drug) can be achieved.

The financialisation of global health.

Global health is increasingly reliant on financial markets. The ongoing financialisation of global health raises new questions of governance, which we expect to affect policy makers as much as doctors, nurses and patients in the years to come. In this editorial, we will first explain what is meant by financialisation, then illustrate its nature in the field of global health via three examples, and end by highlighting some of the governance issues that the financialisation of global health raises.