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Hypothesis: Small scale Marangoni motors, which self-generate motion by inducing surface tension gradients on water interfaces through release of surface-active "fuels", have recently been proposed as self-powered mixing devices for low volume fluids. Such devices however, often show self-limiting lifespans due to the rapid saturation of surface-active agents. A potential solution to this is the use volatile surface-active agents which do not persist in their environment. Here we investigate menthyl acetate (MA) as a safe, inexpensive and non-persistent fuel for Marangoni motors., Experiments: MA was loaded asymmetrically into millimeter scale silicone sponges. Menthyl acetate reacts slowly with water to produce the volatile surface-active menthol, which induces surface tension gradients across the sponge to drive motion by the Marangoni effect. Videos were taken and trajectories determined by custom software. Mixing was assessed by the ability of Marangoni motors to homogenize milliliter scale aqueous solutions containing colloidal sediments., Findings: Marangoni motors, loaded with asymmetric "Janus" distributions of menthyl acetate show velocities and rotational speeds up to 30 mm s -1 and 500 RPM respectively, with their functional lifetimes scaling linearly with fuel volume. We show these devices are capable of enhanced mixing of solutions at orders of magnitude greater rates than diffusion alone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Superconducting spintronics explores the interplay between superconductivity and magnetism, sparking substantial interest in nonunitary superconductors as a platform for magneto-superconducting phenomena. However, identifying nonunitary superconductors remains challenging. We demonstrate that spin current driven by thermal gradients sensitively probes the nature of the condensate in nonunitary superconductors. Spin polarization of the condensate in momentum space induces the superconducting spin Seebeck effect, where a spin current is generated along thermal gradients without a thermoelectric charge current. Notably, the nonvanishing superconducting spin Seebeck effect provides a smoking gun evidence of nonunitary superconductivity because it reflects the spin polarization of the condensate in momentum space, irrespective of whether the net pair spin magnetization vanishes. At the same time, the spin chirality of the condensate induces the spin Nernst effect, where a spin current is generated perpendicular to thermal gradients in nonunitary superconductors. These spin caloritronic phenomena offer a definitive probe of nonunitary superconductors.

Transition metal dichalcogenides (TMDs) exhibit unique properties and potential applications when reduced to one-dimensional (1D) nanoribbons (NRs), owing to quantum confinement and high edge densities. However, effective growth methods for self-aligned TMD NRs are still lacking. We demonstrate a versatile approach for lattice-guided growth of dense, aligned MoS 2 NR arrays via chemical vapor deposition (CVD) on anisotropic sapphire substrates, without tailored surface steps. This method enables the synthesis of NRs with widths below 10 nanometers and longitudinal axis parallel to the zigzag direction, being also extensible to the growth of WS 2 NRs and MoS 2 -WS 2 heteronanoribbons. Growth is influenced by both substrate and CVD temperature, indicating the role of anisotropic precursor diffusion and substrate interaction. The 1D nature of the NRs was asserted by the observation of Coulomb blockade at low temperatures. Pronounced catalytic activity was observed at the edges of the NRs, indicating their promise for efficient catalysis.

Vibrio cholerae, the causative agent of cholera, displays remarkable adaptability to diverse environmental conditions through morphological changes that enhance its pathogenicity and influence the global epidemiology of the disease. This study examines the motility differences between filamentous and comma-shaped forms of the V. cholerae O1 strain under various viscosity conditions. Utilizing the El Tor strain, we induced filamentous transformation and conducted a comparative analysis with the canonical comma-shaped morphology. Our methodology involved assessing motility patterns, swimming speeds, rotation rates, kinematics, and reversal frequencies using dark-field microscopy and high-speed imaging techniques. The results show that filamentous V. cholerae cells retain enhanced motility in viscous environments, indicating an evolutionary adaptation for survival in varied habitats, particularly the human gastrointestinal tract. Filamentous forms exhibited increased reversal behavior at mucin interfaces, suggesting an advantage in penetrating the mucus layer. Furthermore, the presence of filamentous cells in bile-supplemented medium underscores their relevance in natural infection scenarios., Importance: This study highlights the enhanced motility of filamentous Vibrio cholerae in viscous environments, an adaptation that may provide a survival advantage in the human gastrointestinal tract. By demonstrating increased reversal behavior at mucin interfaces, filamentous V. cholerae cells exhibit a superior ability to penetrate the mucus layer, which is crucial for effective colonization and infection. Filamentous cells in bile-supplemented media further underscores their potential role in disease pathogenesis. These findings offer critical insights into the morphological flexibility of V. cholerae and its potential implications for infection dynamics, paving the way for more effective strategies in managing and preventing cholera outbreaks., Competing Interests: The authors declare no conflict of interest.

Most kinesin molecular motors dimerize to move processively and efficiently along microtubules; however, some can maintain processivity even in a monomeric state. Previous studies have suggested that asymmetric potentials between the motor domain and microtubules underlie this motility. In this study, we demonstrate that the kinesin-3 family motor protein KLP-6 can move forward along microtubules as a monomer upon release of autoinhibition. This motility can be explained by a change in length between the head and tail, rather than by asymmetric potentials. Using mass photometry and single-molecule assays, we confirmed that activated full-length KLP-6 is monomeric both in solution and on microtubules. KLP-6 possesses a microtubule-binding tail domain, and its motor domain does not exhibit biased movement, indicating that the tail domain is crucial for the processive movement of monomeric KLP-6. We developed a mathematical model to explain the biased Brownian movements of monomeric KLP-6. Our model concludes that a slight conformational change driven by neck-linker docking in the motor domain enables the monomeric kinesin to move forward if a second microtubule-binding domain exists., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Biophysical Society. Published by Elsevier Inc. All rights reserved.)

Thermoelectric technology plays an important role in developing sustainable clean energy and reducing carbon emissions, offering new opportunities to alleviate current energy and environmental crises. Nowadays, GeTe has emerged as a highly promising thermoelectric candidate for mid-temperature applications, due to its remarkable thermoelectric figure of merit ( ZT ) of 2.7. This review presents a thorough overview of the advancements in GeTe thermoelectric materials, meticulously detailing the crystal structure, chemical bonding characteristics, band structure, and phonon dynamics to elucidate the underlying mechanisms that contribute to their exceptional performance. Moreover, the phase transition in GeTe introduces unique degrees of freedom that enable multiple pathways for property optimization. In terms of electrical properties, noticeable enhancement can be realized through strategies such as band structure modulation, carrier concentration engineering, and vacancy engineering. For phonon transport properties, by incorporating defect structures with varying dimensions and constructing multi-scale hierarchical architectures, phonons can be effectively scattered across different wavelengths. Additionally, we provide a summary of current research on devices and modules of GeTe. This review encapsulates historical progress while projecting future development trends that will facilitate the practical application of GeTe in alignment with environmentally sustainable objectives., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Humans exploit motor synergies for motor control; however, how they emerge during motor learning is not clearly understood. Few studies have dealt with the computational mechanism for generating synergies. Previously, optimal control generated synergistic motion for the upper limb; however, it has not yet been applied to the high-dimensional whole-body system. We investigated the emergence of synergies through deep reinforcement learning of whole-body locomotion tasks. We carried out a joint-space synergy analysis on whole-body control solutions for walking and running agents in simulated environments. Although a synergy constraint was never encoded into the reward function, the synergy emerged during the learning of walking and running tasks. To investigate the effect of gait symmetry on synergy emergence, we varied the weight level of symmetry loss. Interestingly, increasing the weight of symmetry loss resulted in increased energy efficiency and synergetic motion patterns concurrently. These results illustrate the correlation between motor synergy, energy efficiency, and gait symmetry in whole-body motor learning, reflecting that deep reinforcement learning can generate synergistic gait for highly redundant joint systems, similar to human motor control. This suggests that locomotor synergies can emerge through learning processes, complementing the understanding of synergy emergence mechanisms., Competing Interests: Declarations. Competing interests: The authors declare that they have no competing interests., (© 2024. The Author(s).)

Epithelial-mesenchymal transition (EMT) is a drastic and important cellular process by which epithelial cells acquire a mesenchymal phenotype. Herein, we evaluated EMT-induced membrane variations using scanning ion conductance microscopy (SICM), which allows noninvasive nanoscale visualization. The results showed that the number and size of ruffles on the living cell surface decreased as the EMT progressed. It was also shown that the overall cell shape change occurred first rather than the nanoscale morphological variations. Time-lapse imaging using SICM showed that the small ruffles still moved actively after EMT induction. This study indicates that surface shape measurements using SICM may be useful indicators for assessing EMT progression.

The current situation of COVID-19 measures makes it difficult to accurately assess the prevalence of SARS-CoV-2 due to a decrease in reporting rates, leading to missed initial transmission events and subsequent outbreaks. There is growing recognition that wastewater virus data assist in estimating potential infections, including asymptomatic and unreported infections. Understanding the COVID-19 situation hidden behind the reported cases is critical for decision-making when choosing appropriate social intervention measures. However, current models implicitly assume homogeneity in human behaviour, such as virus shedding patterns within the population, making it challenging to predict the emergence of new variants due to variant-specific transmission or shedding parameters. This can result in predictions with considerable uncertainty. In this study, we established a state-space model based on wastewater viral load to predict both reported cases and potential infection numbers. Our model using wastewater virus data showed high goodness-of-fit to COVID-19 case numbers despite the dataset including waves of two distinct variants. Furthermore, the model successfully provided estimates of potential infection, reflecting the superspreading nature of SARS-CoV-2 transmission. This study supports the notion that wastewater surveillance and state-space modelling have the potential to effectively predict both reported cases and potential infections.

This study addressed a less-reported issue: the insufficient alkalinity encountered when anaerobic membrane bioreactors (AnMBRs) are used to treat municipal wastewater (MWW). In the present study, a 20-L AnMBR was initiated at an MWW treatment plant. During the initial startup, a continuous decrease in pH was observed. Through the analyses of the balance between HCO 3 - in the biogas and alkalinity in the reactor, the cause of pH instability was determined to be that the alkalinity could not balance the acidity induced by the continuous dissolution of CO 2 from biogas in the liquid phase. Therefore, this study employed the in-situ removal of CO 2 from biogas in the liquid phase. Therefore, this study employed the in-situ removal of CO 2 partial pressure, thereby achieving stable control of the pH in the reactor. This study provides valuable experience and technical support for anaerobic processes for treating low-alkalinity MWW in the future applications.2 partial pressure, thereby achieving stable control of the pH in the reactor. This study provides valuable experience and technical support for anaerobic processes for treating low-alkalinity MWW in the future applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this study, amino acid waste liquid was employed as a functional supplement (designated as amino acid-rich FS) in the up-flow anaerobic sludge blanket (UASB) treatment of methanolic wastewater. The effect of amino acid-rich FS was evaluated through repeated batch tests, showing that a 0.5% and 1% dosage increased the maximum methane production rate by 93.60% and 123.04%, respectively, by promoting faster methanol degradation. Additionally, long-term operation of the UASB reactor was conducted with increased dosages of amino acid-rich FS, resulting in improved performance. Microbial community analysis demonstrated that the addition of amino acid-rich FS enhanced microbial diversity, with the abundance of Sporomusa increasing by 47.5 times. Beyond the original cooperative relationships, an additional synergy between Sporomusa and Methanosarcina was observed. These findings could address the key challenge of limited microbial diversity in the anaerobic treatment of methanolic wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Anaerobic digestion combined with partial nitritation/anammox technology holds promising potential for the carbon-neutral treatment of nitrogenous industrial organic wastewater, boasting remarkable advantages in effective removal of both organic matters and nitrogen, bio-energy recovery and carbon emission reduction. This study provides a concise overview of the development and advantages of anaerobic digestion combined with partial nitritation/anammox technology for treating nitrogenous industrial organic wastewater. The process excels in removing organic matter and nitrogen, recovering bio-energy, and reducing carbon emissions, compared to traditional physicochemical and biological methods. Case studies highlight its energy-saving and efficient attributes, especially for carbon-neutral nitrogen removal. Challenges for achieving stable operation in the future are discussed, and the study offers insights into the broader application of this integrated process in industrial wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)