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Abstract Due to the sulfur’s atoms’ propensity to form molecules and/or polymeric chains of various sizes and configuration, elemental sulfur possesses more allotropes and polymorphs than any other element at ambient conditions. This variability of the starting building blocks is partially responsible for its rich and fascinating phase diagram, with pressure and temperature changing the states of sulfur from insulating molecular rings and chains to semiconducting low- and high-density amorphous configurations to incommensurate superconducting metallic atomic phase. Here, using a fast compression technique, we demonstrate that the rapid pressurisation of liquid sulfur can effectively break the molecular ring structure, forming a glassy polymeric state of pure-chain molecules (Am-S P ). This solid disordered chain state appears to be (meta)stable in the P-T region usually associated with phase I made up of S8. The elemental sulfur glass, made up from one of the simplest building blocks, offers a unique prospect to study the structure and property relationships of various other phases of sulfur and their interactions. More importantly, the fast compression technique performed at any temperature effectively like thermal quenching, opening up possibilities in high pressure synthesis by providing an effective and fast way of changing the fundamental thermodynamical parameter.

Abstract Protein therapeutics are essential in treating various diseases, but their inherent biological instability and short circulatory half-lives in vivo pose challenges. Herein, a quantitative one-pot iterative living polymerization technique is reported towards precision control over the molecular structure and monomer sequence of protein-polymer conjugates, aiming to maximize physicochemical properties and biological functions of proteins. Using this quantitative one-pot iterative living polymerization technique, we successfully develop a series of sequence-controlled protein-multiblock polymer conjugates, enhancing their biostability, pharmacokinetics, cellular uptake, and in vivo biodistribution. All-atom molecular dynamics simulations are performed to disclose the definite sequence-function relationship of the bioconjugates, further demonstrating their sequence-encoded cellular uptake behavior and in vivo biodistribution in mice. Overall, this work provides a robust approach for creating precision protein-polymer conjugates with defined sequences and advanced functions as a promising candidate in disease treatment.

Abstract Geothermal power generation employing Organic Rankine Cycle (ORC) technology is a widely acknowledged and conventional approach for harnessing geothermal energy. In an innovative advancement, we propose a novel design integrating downhole thermoelectric power generation with a coaxial borehole heat exchanger. This design aims to enhance the efficiency and sustainability of geothermal energy utilization. In this innovative design, the geothermal well is divided into two distinct sections: a power generation section and a heat exchanging section, achieved through the implementation of a packer positioned from the uppermost part of the targeted zone. The process involves the injection of cold fluid downhole via an insulated pipe. Subsequently, a portion of the injected fluid is directed to flow in reverse within the casing-tubing annulus above the packer, while another portion circulates into the casing-tubing annulus below the packer before ascending through the tubing. This dual flow mechanism establishes distinct cold and hot sources for the thermoelectric generator, a key feature facilitated by this innovative design. Analytical models detailing of downhole temperature distribution for thermoelectric power have been meticulously developed. A comprehensive case study, focusing on a geothermal well with 3000 m length of power generation section and 500 m heat exchanging section, has been conducted. The results indicate that a significant generating capacity could be achieved with a higher wellhead temperature, and the payback period under different carbon tax scenarios is about 6–8 year. Furthermore, the effects of injection rate, fluid diversion ratio, and casing-tubing configuration on power performance and thermal-electricity efficiency are also discussed. This method not only enables the concurrent harvesting of geothermal energy and power generation but also operates consistently throughout the year. The results thus emphasize the viability and economic feasibility of the proposed approach.

Emergence of the Omicron BA.1/2 SARS-CoV-2 subvariants led to a wave of infection South Africa. Here, the authors use serological data from a prospective household study to characterise infection rates in the context of diverse immune histories following vaccination and exposure to different variants.

The electrochemical additive manufacturing technique based on the meniscus-confined approach has been proved to be a powerful tool for fabricating nanoscale and microscale metal components. The stability of the meniscus is the key in this meniscus-confined approach to achieve high resolution and reliable product quality. In the present study, a double-nozzles design, which consists of a feed nozzle and a suction nozzle, is proposed for the meniscus confined electrochemical additive manufacturing technique. It was demonstrated that the proposed design possessed robust control of the stability of the meniscus by manipulating the feed and suction rates of the two nozzles in a quite large range. Various sizes of menisci can be easily obtained by utilising nozzles with different sizes. Compared with the pressure-controlled single-nozzle approach, the results showed that dense structures without dendrites can be fabricated by the double-nozzles design with larger current density due to the feed-and-suction process at the tip of the nozzles. The proposed flow-rate-controlled double-nozzles design was finally employed to fabricate some copper circuits and a Cu/CuNi thin film thermocouple to demonstrate its potential in fabricating electronic devices.

Abstract Composite gel polymer electrolyte (CGPE), derived from ceramic fillers has emerged as one of the most promising candidates to improve the safety and cycling stability of lithium metal batteries. However, the poor interface compatibility between the ceramic phase and polymer phase in CGPE severely deteriorates lithium‐ion pathways and cell performances. In this work, a fluorescent ceramic nanowire network that can palliate the energy barrier of photoinitiators and contribute to preferential nucleation and growth of polymer monomers is developed, thus inducing polymer segment orderly arrangement and tightly combination. A proof‐of‐concept study lies on fabrications of poly(ethylene oxide) closely coating on the ceramic nanowires, thus dividing the matrix into mesh units that contribute to directional lithium‐ion flux and dendrite‐free deposition on the metallic anode. The CGPE, based on the state‐of‐the‐art self‐luminous framework, facilitates high‐performance quasi‐solid‐state Li||LiFePO4 cell, registering a high capacity of 143.3 mAh g−1 after 120 cycles at a mass loading of 12 mg cm−2. X‐ray computed tomography provides an insight into the relationship between directional lithium‐ion diffusion and lithium deposition behavior over the electrochemical processes. The results open a door to improve the electrochemical performances of composite electrolytes in various applications.

Detailed knowledge of COVID-19 epidemiology is needed to inform public health responses. Here, the authors use large-scale contact tracing data to provide empirical estimates of key parameters, and show that susceptibility increases with age but transmissibility does not vary significantly.

The effects of ultrasound-assisted glycosylation (UG) with glucose (GLU) on the emulsifying properties, foaming properties, gelling properties, and structural properties of fish gelatin (FG) were investigated. It was shown that UG with high power and a long duration facilitated the Maillard reaction through the reduction of the free amino acid contents. UG significantly improved the emulsifying ability index and foaming capacity of FG whilst decreasing the gel strength. Rheological analysis showed that UG modification prolonged the gelling time by hindering the triple-helix formation and decreasing the apparent viscosity of the gelatin solution. Structural analysis showed that UG treatment changed the secondary structure of the gelatin molecule by the formation of Millard reaction products (MRPs). Moreover, the UG treatment generally decreased the bound water contents of the gelatin gels with an increase in free water.

Summary: In this work, a spinel single-crystalline Li1.1Mn1.9O4 has been successfully synthesized using β-MnO2 nanotubes as the self-sacrifice template. The tubular morphology was retained through solid-state reactions, attributed to a minimal structural reorganization from tetragonal β-MnO2 to spinel Li1.1Mn1.9O4. The materials were investigated as sorbents for lithium recovery from LiCl solutions, recycled using H2SO4 and (NH4)2S2O8. Li1.1Mn1.9O4 nanotubes exhibited favorable lithium extraction behavior due to tubular nanostructure, single-crystalline nature, and high crystallinity. (NH4)2S2O8 eluent ensures the structural stability of Li1.1Mn1.9O4 nanotube, registering a Li+ adsorption capacity of 39.21 mg g−1 (∼89.73% of the theoretical capacity) with only 0.08% manganese dissolution after eight adsorption/desorption cycles, compared to that of 1.21% for H2SO4. It reveals the degradation of sorbent involves with the volume change, Mn reduction, and Li/Mn ratio depletion. New strategies, based on nanotube adsorbent and (NH4)2S2O8 eluent, can extract lithium ions at satisfactorily high degrees while effectively minimizing manganese dissolution.

Abstract We investigate the effects of modular and temporal connectivity patterns on epidemic spreading. To this end, we introduce and analytically characterise a model of time-varying networks with tunable modularity. Within this framework, we study the epidemic size of Susceptible-Infected-Recovered, SIR, models and the epidemic threshold of Susceptible-Infected-Susceptible, SIS, models. Interestingly, we find that while the presence of tightly connected clusters inhibits SIR processes, it speeds up SIS phenomena. In this case, we observe that modular structures induce a reduction of the threshold with respect to time-varying networks without communities. We confirm the theoretical results by means of extensive numerical simulations both on synthetic graphs as well as on a real modular and temporal network.

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-22487-4