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International audience; China has experienced unprecedented urbanization and associated rural depopulation during recent decades alongside a massive increase in the total population. By using satellite and demographical datasets, we here test the hypothesis that urbanization and carbon neutrality are not mutually exclusive and that sustainably managed urbanization may even be an integral part of the pathway to reduce atmospheric CO2. We show that, although urban expansion caused an initial aboveground carbon loss of −0.02 PgC during 2002–2010, urban greening compensates these original losses with an overall balance of +0.03 PgC in urban areas during 2002–2019. We further show that a maximum increase in aboveground carbon stocks was observed at intermediate distances to rural settlements (2–4 km), reflecting the decreased pressure on natural resources. Consequently, rural areas experiencing depopulation (−14 million people yr−1) coincided with an extensive aboveground carbon sink of 0.28 ± 0.05 PgC yr−1 during 2002–2019, while at the same time only a slight decline in cropland areas (4%) was observed. However, tree cover growth saturation limits the carbon removal capacity of forests and only a decrease in CO2 emissions from fossil fuel burning will make the aim of carbon neutrality achievable.

International audience; The evaporation of a colloidal dispersion is characterized by solute accumulation at the air-liquid interface, leading to the gradual formation of a gelled skin. The development of this layer, from preliminary colloid deposit to complete solidification, affects overall drying process and final sample morphology. Despite, progress in the last decades, the mechanisms governing skin formation in drying colloidal suspensions have not yet been fully clarified, especially in complex polydisperse systems. In this work, we investigate this open question in droplets consisting of the two main milk proteins, i.e. whey proteins and casein micelles. Using complementary experimental approaches, we evaluate skin rheological behavior during the different stages of the evaporation process, highlighting the specific role of each colloid. Our results are interpreted in the light of drying-induced protein stratification, whose evidence is provided by the direct observation of dry skin section structure. This study contributes to the understanding of the competitive drying mechanisms occurring in binary colloidal systems. Moreover, our outcomes are potentially valuable for the optimization of milk powder production in dairy industry.

International audience; The aim of this study is to investigate the interaction characteristics between human upper extremity limb and mobility assistance device, in order to test the effects of different device designs on human arm movement. In this paper, the role of mobility-aid for the human arm was depicted by an ideal generalized spring force appended onto the human elbow joint. The main contribution of this work resides in the use of musculoskeletal modelling and predictive simulation to describe the interaction by exploiting the variables of the equivalent spring force during an elbow flexion movement. Results showed that the different variables of the spring force would result in a variety of levels of human muscle activation, where we can draw a conclusion that interaction characteristics affect the human arm movement. Besides, it is also available for recommending the most suitable force variables in terms of minimization of muscle activation.

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Trace metal ions play many critical roles in biological functions in humans. Plasma proteins such as human serum albumin (HSA) are primarily responsible for the circulatory transport of metal ions and as such are relevant to health and immune functioning. To further understand the biological processes and some diseases associated with defective homeostasis of metal ions (including Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺), a deeper understanding of the properties of protein-metal ion interactions is required. On HSA, three metal-binding sites involving in binding to these metal ions are known, including sites A (His67 site), B (His9 site) and the N-terminal site (His3 site), which play different roles in binding different metal ions. Additionally, metal ion states are of clinical importance in immune system. Among these metal ions, defective homeostasis of Cu²⁺ has been proposed to be related to the development of celiac disease (CD), by regulating tissue transglutaminase (TG2) activity in extracellular environment. Thus, the aims of this project are to elucidate properties of metal ion-HSA interactions and investigate potential role for Cu²⁺ in TG2 activity regulation. Employing site-directed mutagenesis, isothermal titration calorimetry (ITC) and circular dichroism (CD), the results presented here indicate that Co²⁺ preferentially binds to HSA at site B, followed by site A and subsequentially binds to multiple weak-affinity sites. Additionally, the presence of 5 molar equivalents of palmitate can trigger structural changes and diminish Co²⁺ binding to sites A and B of HSA. An investigation of Zn²⁺ binding using mutagenesis and ITC revealed that this ion preferentially binds to site A, followed by site B, which is in firm agreement with previous data. In addition, Zn²⁺ binding to site A was dramatically reduced by addition of 5 molar equivalents of palmitate. ITC results in combination with ¹¹¹Cd-NMR spectroscopy suggest sites B and A are the two major binding sites participating in Cd²⁺ binding to HSA. Additionally, the results confirm that His9 is the indispensable histidine residue contributing to site B. Intriguingly, inspection of these data reveals that binding modes of different metal ions in different metal-binding sites (especially in site A) vary substantially. Both His67 and His247 participate in the “intact” site A in Zn²⁺ binding; however, His247 may play a less important role than His67 in Co²⁺ and Cd²⁺ binding to site A. Regarding to Cu²⁺ binding to HSA, it primarily binds to the N-terminal site and secondly binds to site A, supported by the results from ITC and EPR spectroscopy. Compellingly, the data presented here also demonstrate that Cu²⁺ is a potent inhibitor of TG2, providing an insight into deeper understanding of the development of CD. Collectively, these data provide a more comprehensive understanding of the properties of Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺ interactions with HSA and their interplay with fatty acids, contributing to more accurate insights into metal ion distribution and speciation mediated by HSA and their implications in health.

International audience; In this study, an original radiolytic method, based on pulsed electron beam irradiation, is used for the synthesis of conducting PEDOT in an aqueous solution containing EDOT monomers in the presence of potassium persulfate, K2S2O8, at 0 degrees C. At this low temperature, EDOT monomers are not chemically oxidized by S2O82- anions, initiating PEDOT polymerization, but are rather oxidized by sulfate radicals, SO4 center dot-, which are radiolytically generated by the reaction of solvated electrons, produced by water radiolysis, with persulfate anions. Successfully, as demonstrated by UV-vis absorption spectrophotometry and ATR-FTIR spectroscopy, irradiating the aqueous solution, by using a series of accumulated electron pulses, enables complete EDOT oxidation and quantitative in situ PEDOT polymerization through a step-by-step oxidation mechanism. The morphology of PEDOT polymers, mixed with tin reacted K2S2O8 salt, is characterized by Cryo-TEM microscopy in aqueous solution and by SEM after deposition. Successfully, in the absence of any washing step, high resolution AFM microscopy, coupled with infrared nanospectroscopy, is used to discriminate between the organic polymers and the inorganic salt and to, probe the local chemical composition of PEDOT nanostructures. The results demonstrate that PEDOT polymers form globular self-assembled nanostructures which preferentially adsorb onto unreacted K2S2O8 solid nanoplates. The present results first demonstrate the efficiency of sulfate radicals as oxidizing species for the preparation of nanostructured PEDOT polymers and second highlight the promising potentiality of electron accelerators in the field of conducting polymers synthesis. (C) 2016 Elsevier Ltd. All rights reserved.

This thesis examines how film festival venues participate in shaping broader film cultures. It proposes an approach to studying film festivals that is founded on looking at their physical spaces instead of merely focusing on the social space of film festivals. The physical sites, as essential and tangible elements and practices of film festivals (and ones entangled with questions of capital and power), play an essential role in representing films, presenting places, and navigating audiences. As such, they open up a productive route for understanding how festivals shape film cultures. Two major case studies – the International Film Festival Rotterdam (IFFR) and the Shanghai International Film Festival (SIFF) – are analysed in this thesis, along with a case study of SIFF and IFFR during the COVID-19 pandemic. The festival venue is approached in terms of three key considerations in three layers: the geographical locations of film festivals, urban space and film festivals, and event sites of film festivals. This research contributes to the field of film festival studies and engages with the broader field of film cultures by highlighting the role of festival venues in presenting film cultures and drawing attention to the material basis of the global film festival circuit. Given the tremendous impact of film festivals' locations and venues – as material and physical features of festivals – on local and global film cultures, I argue that film festivals' venues should be examined in relation to the festivals' intangible formations. It can help us further understand how film festivals have been shaped by the political economy relating to location and how they occupy urban space and engage with the diversity of exhibition practices and space.

This thesis examines two types of perspectival attitudes and assertions: those about oneself, such as "I am in Martyrs Kirk Library" or "my house is on fire", and those about matters of personal tastes, such as "Super Mario is a fun game" or "century eggs are disgusting". The aim of this thesis is to challenge some published arguments in favour of the relativist, centred-worlds framework for these attitudes and assertions and to offer novel explanations for relevant phenomena including the inferior status of testimony about taste matters, the acquaintance inference of taste assertions, the connection between de se attitudes and actions, and the non-reducibility of de se attitudes to non-de se attitudes. I argue that the centred-worlds framework is not a well-motivated framework for these two types of attitudes and assertions. In addition, I propose that taste assertions are governed by a special knowledge-why norm, and de se attitudes have impossible-worlds contents.

redacted “I would like to thank the Chinese Scholarship Council and the St Leonard Scholarship for their financial support. I also would like to thank the Cirrus UK National Tier-2 HPC Service at EPCC for a grant of CPU time.”-- Acknowledgements

Due to the rapid development of the Internet, modern daily behaviour has become more efficient and convenient. The Internet has become an indispensable element in our daily life, providing significant resources to people whether for play, work or education. In addition, with the increased universality of mobile devices, a magnitude of services is at our fingertips, the efficiency of our life or work has improved. However, the negative side of this is the increase in cybercrimes, with large losses for both individuals and enterprises. Phishing is currently defined as a criminal mechanism employing both social engineering and technical subterfuge to gather any useful information such as user personal data or financial account credentials. Phishing threats have been in existence for many years, since the establishment of the Internet, and they have continuously evolved and increased in application. So far, phishing attacks have accounted for a large proportion of all malicious attacks, and they are a globally growing threat with an increasing frequency of known attacks. Phishing attacks are a major current cyber threat as they are always cheap to produce and easy to deploy, in particular, due to the development of E-commerce, either to an individual user or organization. For the individual, sensitive credentials are always of interest to phishers due to the development of E-commerce. For an enterprise, a successful phishing attack, such as a subdomain takeover attack, may affect their organization’s reputation as well as cause financial loss. Currently, most security vendors have been using different approaches to prevent phishing attacks. However, these solutions cannot keep up with the constant updating of phishing websites. In this thesis, web phishing attack types are classified into three different categories, from the shallower to the deeper. They are General Phishing Attack, Advanced Phishing Attack and Subdomain Takeover Attacks. The purpose of this thesis is to present an effective mitigation to defend against these phishing threats. From the shallower approach to a deeper, more complex approach, according to our defined categories of phishing threats, the specific mitigations and contributions are presented.

Janus face fluorocycloalkanes (JFC) represent a novel subject of study. The fluorinated electronegative face and the hydrogenated electropositive face of the rings create an extraordinarily high dipole moment which induces facial polarity. This thesis carries out various studies on this new class of compound. In Chapter 1, a discussion of the background and general interest in fluorine chemistry is given. The role of fluorine in pharmaceutical chemistry is demonstrated. The most recent studies on the JFC are summarised and discussed, including their preparation and applications in ionic binding, supramolecular chemistry, and biological chemistry. In Chapter 2, a recently reported stereoselective Rh-catalysed hydrogenation was further explored, and its substrate scope was extended to aryl–CF₃ to deliver facially polarised CF₃–cyclohexane motifs in high diastereoselectivity. The direct preparation of CF₃–containing cyclohexanes form a library of stereoselective motifs for further studies. In Chapter 3, the study of facially polar CF₃–cyclohexane was extended to the preparation, properties and physiochemistry of all-cis-multi-CF₃ cyclohexanes with between 3 and 6 substituent CF₃ groups. The prepared all-cis-hexakis-CF₃–cyclohexane has a high barrier to ring inversion (27 kcal mol⁻¹), more than twice that of cyclohexane. This ring also coordinates chloride (Cl-) ion to the hydrogen face with a modest affinity constant (K = 10³ M⁻¹). In Chapter 4, the surface behaviour of the all-cis-hexafluorocyclohexane was studied on HOPG and gold surfaces. The reactivity of JFCs was studied, and a number of functional groups were installed onto the ring. of A novel amino acid of with a JFC side chain was prepared and incorporated into peptide synthesis. In Chapter 5, trifluoro substituted cyclohexanes were prepared. An unexpected triaxial preference was found in all-cis-1,3,5-trifluorocyclohexane and some of its derivatives. The conformational preferences of these derivatives were also investigated. In Chapter 6, the JFC motifs were transformed into multi-dentate supramolecular architectures. The proposed frameworks were synthesized in modular approaches. The crystal structure of a number of the building blocks were demonstrated with voids in their supramolecular architectures. “I gratefully acknowledge the funding body China Scholarship Council (CSC) for PhD studentship. No. 201703780007”—Acknowledgements

redacted "This work was supported by the University of St Andrews and the China Scholarship Council (CSC) joint program (File No. 201808440262)." -- Acknowledgements

redacted "I gratefully acknowledge my funding from China Scholarship Council. Thanks to the University of St Andrews for providing a friendly environment through my PhD study."--Acknowledgements

This thesis investigates the impact of political uncertainty and regulatory change on the behaviour of Chinese listed firms. In Chapter 2, the impact of political uncertainty on corporate cash holdings of private Chinese firms is investigated. The ascent to power of President Xi and resultant political uncertainty caused by the unexpected removal of ten provincial leaders is used as a setting. The results suggest that corporate cash holdings increase for private firms located in provinces where changes to political leadership took place relative to counterparts where no such change occurred. The observed increase is more pronounced for firms with higher levels of bank debt and substantive agency conflicts. In Chapter 3, the impact of board independence on dividend payouts is investigated. The 2001 ‘Guideline for The Establishment of Independent Director System in Chinese Listed Companies’ is used as an exogenous shock. This guideline required that at least one-third of the corporate board be composed of independent directors. The results suggest that dividend payouts increase at affected firms (those with fewer than one-third independent directors at the time when the 2001 regulation was enacted). This is more pronounced for firms, which have independent directors with multiple directorships. In Chapter 4, the impact of academic independent directors on green innovation is investigated. A policy change (the implementation of the ‘Notice on the Special Inspection of the Part-time Positions of Party and Government Leading Cadres in Enterprises’ in 2015) which mandated the resignations from corporate boards of many senior academics with administrative roles in universities is used as a setting. The results suggest that the resignation of academic independent directors leads to a decrease of green innovation. The observed decrease is more pronounced for firms where female academics, academics with overseas experiences and industrial expertise, and academics employed at top-ranking universities resigned.

Lipid-protein interactions are crucial for life. Research into this area is continuously growing, not only in the context of basic science, but also from a technological perspective aiming to facilitate their handling and stability for further studies. The development of nanodisc (ND) technology, with apolipoprotein-A1 derived membrane scaffold protein (MSP), has become key to the study of lipid-protein complexes, including mechanosensitive (MS) proteins. Although it is a widely used artificial lipid environment for membrane proteins in vitro, how ND structures assembly together remains poorly understood. In this thesis, I apply ensemble and single-molecule Förster Resonance Energy Transfer (FRET) assays to investigate the dynamics of ND structures and ND-reconstituted MS channels. First, I describe a FRET-based characterization of NDs. My studies reveal the stepwise mechanism of ND assembly and disassembly, the timescales of these processes and the stability of ND under detergents with or without the membrane protein. Next, I use this MSP-ND technology to investigate the structure of the pentameric MS channel of large conductance (MscL), which has attracted considerable attention over the past years. MS channels allow cells to sense and response to external mechanical stimuli. However, most studies have used ensemble measurements providing only average-conformation values. Here, I present a library of FRET-labelled MscL proteins to characterize the conformation of MscL channels at single-molecule level. Lastly, completely understanding mechanosensation requires to manipulate membrane tension and simultaneously image their response one by one. In the last part of this thesis, I demonstrate the feasibility of incorporating magnetic beads inside Giant Unilamellar Vesicles (GUVs) as a step towards the future development of a combined FRET-magnetic tweezers to explore mechanosensation under varying tension. Overall, this project expands our knowledge of NDs and explores potential methods to study single MS channels by fluorescence-force hybrid microscopy.

The dopaminergic system plays a crucial role in learning, reward-processing, motivation, motor control and attention. The population of midbrain dopamine neurons projects extensively to many areas of the brain. This system is maintained in a homeostatic way, and it can self-regulate to maintain behavioural function in extreme cases such as Parkinson’s disease. However, Huttunen (2016) discovered a significant correlation between midbrain dopamine neuron number in male rats and their behavioural performances in a gambling task. It was unexpected that such non-clinical variation in dopamine neuron number can lead to differences in observable behaviours. Our project aims to investigate the link between dopamine structure and function in risk decision-making, and to explore possible factors that can manipulate the brain and behaviour. Chapter 1 reviewed the dopaminergic system and its adaptive role in conditions such as environmental enrichment and stress. Chapter 2 described the experiment using a modified risk task which failed to replicate the original results from Huttunen (2016). Chapter 3 examined the possible sex difference in the brain of behaviour of rats. Chapter 4 and 5 explored factors that can influence this dopamine-loss-stay relationship, including environmental enrichment and neurogenesis. We demonstrated that dopamine-expressing neurons in the rat midbrain may underlie loss-stay behaviours, which may reflect the animals’ risk-attitude. Moreover, the correlation was significant only when the age of the animal was considered. Therefore, this correlation may be a result of aging, or the compensatory mechanisms that often accompany ageing. Future research may shed light on possible treatment and interventions for neural decline in ageing and other clinical conditions.

International audience; Aortic valve landmarks detection in Computed Tomography (CT) images is essential for planning Transcatheter Aortic Valve Implantation (TAVI) and establishing predictive factors of cardiac conduction disturbance. The fully automatic detection facilitates the measurement and planning while reducing interobserver variability. Although the emerged Convolutional Neural Networks (CNNs) have been applied to fully automatic landmark detection, it is challenging for CNNs to directly process large-scale CT volumes due to the limited computational resources. Some common preprocessing to deal with the limitation of resources, such as down-sampling or center cropping, can cause the volume to lose detailed features or global information. To address these issues, we propose a two-stage detection method based on CNN. The proposed method initially detects the approximate positions of the landmarks in the global view and then obtains refined results in local regions, without overdependence on prior knowledge or labor-intensive preprocessing. Eight important aortic valve landmarks, including three hinge points, three commissure points, the middle point of the cusps, and the point of the lower part of the membranous septum are automatically detected from our network. An overall result of Mean Radial Error (MRE) of 2.23 mm is yielded from our data set containing 150 individual cardiac CT volumes. The method takes 0.15 seconds per stage to process one volume, showing high efficiency. © 2023 SPIE.

International audience; As a crossroads for plant dispersal between Laurasia and Gondwana since at least the late Eocene, the Central Myanmar Basins have yielded rich and diverse fossil pollen. Here we report Grimmipollis burmanica, a new genus and species in the soapberry family (Sapindaceae) from the upper Eocene Yaw Formation in the Central Myanmar Basins. We also investigate its similarity of pollen sculpture with other selected genera using hierarchical cluster analysis, and its source paleoecology with pollen diagrams. Grimmipollis pollen grains are characterized by parasyncolporate apertures with an apocolpial field at each side, distinct margines along the colpi, arcuate, tuberculate and rope-shaped mesocolpial ridges, and prominent, verrucate or fossulate apocolpia. These features distinguish this genus from other syncolporate and parasyncolporate types in the extant Sapindaceae genera, and fossil pollen genera. As most syncolporate and parasyncolporate types occur in the tribe Cupanieae, G. burmanica is likely derived from an extinct Cupanieae and thus a rainforest tree species. The hierarchical cluster analysis confirms our establishment of Grimmipollis, and reveals it is morphologically close to Meyeripollis. The sedimentary environment from which these pollen grains were retrieved suggests that G. burmanica could be a member of seasonal swamp forests.

redacted "This work was supported by China Scholarship Council (CSC) (grant number 201806050003) and the School of Chemistry at the University of St Andrews." -- Funding

Semiconductors play a vital role in many energy- and environment-related areas, and their performance is often affected by their morphology and architecture. Mesocrystal is a hierarchical structure developed from natural minerals which has been demonstrated to bring unique properties and excellent performance to different materials. Many strategies, including bottom-up assembly of nano-sized building blocks and top-down topotactic transformation have been reported to synthesize a range of materials with mesocrystal structures. However, studies on immobilised mesocrystals are poorly developed, despite the importance of semiconductors in film form for applications. This thesis aims to propose general and facile strategies to prepare immobilized semiconductor mesocrystals using TiO₂ as the model material considering the wide applicability of TiO₂ films. In the first strategy (Chapter 3), TiO₂ mesocrystal films were prepared by simply making a printable paste of the topotactic precursor, NH₄TiOF₃, followed by in-situ topotactic transformation of printed films. The obtained TiO₂ mesocrystal possesses typical structural features of mesocrystals, which brings properties associated with individual nanoparticles and advantages from the crystallographic orientation of nanoparticles. In a specific application, dye-sensitised solar cells (DSSCs), the TiO₂ mesocrystal films were applied as single-layer photoanodes, in which the properties from the structural features were discussed and compared with commercial TiO₂ in detail; and also as scattering layer to make better use of all the structural characteristics. Compared with commercial scattering TiO₂, TiO₂ mesocrystals showed better performance as the scattering layer owing to high dye loading capacity, superior visible light scattering and reasonable charge transport. It is believed that this method simplifies manufacturing processes for mesocrystal films and opens up general opportunities for other functional ceramic films. The second strategy adopts a two-step fabrication route including a near room temperature hydrolysis reaction to produce immobilized rod-like (NH₄)₂TiOF₄ or flower-like NH₄TiOF₃, followed by a topotactic transformation to immobilised TiO₂ mesocrystals. The immobilised TiO₂ mesocrystals were also applied in DSSCs as photoanodes (Chapter 4). Due to the unique structural features of mesocrystals and strong adhesion to the substrate inherited from the immobilized precursors, the immobilised TiO₂ mesocrystals possess a high dye pickup capability and optimal electron transport ability. The average power conversion efficiency from DSSCs based on immobilised TiO₂ mesocrystals is comparable to devices with 2 layers of printed commercial TiO₂ under the same heating condition, with the balanced short-circuit current densities, similar open-circuit voltages and outstanding fill factors. The immobilised TiO₂ mesocrystals synthesized from the second strategy were also applied as photocatalysts for water purification (Chapter 5). The photocatalytic performances were tested by the photodecomposition of different dyes and electrochemical characterisation. The heating programme for the topotactic transformation step has been demonstrated to control the structural and surface properties and thus the electronic and optical properties of the immobilised TiO₂ mesocrystals, leading to different photocatalytic performance towards different dyes. Moreover, the immobilisation of all samples provides generally high reusability of the immobilised TiO₂ mesocrystals. In addition, the precursor materials used in this thesis for the preparation of TiO₂ mesocrystals, (NH₄)₂TiOF₄ and NH₄TiOF₃, have been studied computationally and experimentally (Chapter 6). Attempts have been made to apply the immobilized NH₄TiOF₃ as a photocatalyst for dye degradation. A reasonable degradation efficiency was obtained as a proof of concept.

International audience; This work aims to study the mechanical properties of the interfacial transition zone (ITZ) through both experimental tests and microstructural observations. The study considers a mortar with water-cement ratio of 0.58 and four types of aggregates: sandstone, granite, and two different types of limestone with varying water absorption coefficients. Chemical compositions, physical characteristics, and surface micromorphology of the four aggregates were evaluated using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and water absorption measurements as well as SEM observations. Experimental setups were developed to investigate the bonding behavior of the aggregate-mortar interface. The bonding strength between granite and mortar through direct tensile test varied from 51% to 69% of tensile strength of mortar from young age to mature, while 61% to 74% for sandstone, 48% to greater than 90% and 81% to greater than 102% averagely for black and white limestone respectively. The fact of failure in the bulk mortar indicates ITZ adhesion for limestones may equal or exceed the mortar tensile strength generally from 28-day age. This conclusion is consistent with the results obtained by slant shear test. The significant difference of adhesion behavior of ITZ between two limestones due to their water absorption capability. High-water absorption turns out to be beneficial in forming a strong chemical bond at early age, however, the mineralogy remains the pivot under same surface condition. This chemical bond is evidenced by the failure pattern and morphology of the aggregate surface after failure and the presence of a dense accumulation of portlandite and C-S-H under SEM. © 2023 Elsevier Ltd

International audience; Hydrogen (H2) generation and storage are actively investigated to provide a green source of energy, and formic acid (HCOOH), a major product obtained from the biomass, is regarded as a productive source of H2. Therefore, improvements in heterogeneous catalysts are called for. Here, a novel type of catalyst support is proposed involving simple addition of the mixture of metal ion precursors to core-shell ZIF-8@ZIF-67, followed by reduction with NaBH4, with performances surpassing those obtained using nanocatalysts in ZIF-8 or ZIF-67. The nanocatalysts PdxAg were optimized with ZIF-8@Pd2Ag1@ZIF-67 under visible-light illumination for selective HCOOH dehydrogenation involving a turnover frequency value of 430 h-1 under light irradiation at 353 K. These results also reveal the crucial roles of the Pd sites electronically promoted in the presence of visible by the plasmon resonance and the core-shell light by Ag plasmon advantageous MOF structure. In order to examine the potential of extending this catalyst improvement principle to other catalytic reactions, 4nitrophenol reduction, a benchmarking model of catalytic reaction, was tested, and the results also confirmed the superiority of the performance of ZIF-8@Pd2Ag1@ZIF-67 over Pd2Ag1@ZIF-8 and Pd2Ag1@ZIF-67, confirming the interest in the novel catalyst design.

International audience; The Burma Terrane has yielded some of the earliest pieces of evidence for monsoonal rainfall in the Bay of Bengal. However, Burmese ecosystems and their potential monsoonal imprint remain poorly studied. This study focuses on the late Eocene Yaw Formation (23° N) in central Myanmar, which was located near the equator (c. 5° N) during the Eocene. We quantitatively assessed the past vegetation, climate, and depositional environments with sporomorph diagrams, bioclimatic analysis, and sequence biostratigraphy. We calculated the palynological diversity and drew inferences with rarefaction analysis by comparing with four other middle to late Eocene tropical palynofloras. Palynological results highlight a high floristic diversity for the palynoflora throughout the section formed by six pollen zones characterized by different vegetation. They indicate that lowland evergreen forests and swamps dominated in the Eocene Burmese deltaic plains while terra firma areas were occupied by seasonal evergreen, seasonally dry, and deciduous forests. This vegetation pattern is typical to what is found around the Bay of Bengal today and supports a monsoon-like climate at the time of the Yaw Formation. Bioclimatic analysis further suggests that in the late Eocene, the Yaw Formation was more seasonal, drier, and cooler compared to modern-day climate at similar near-equatorial latitude. More seasonal and drier conditions can be explained by a well-marked seasonal migration of the Intertropical Convergence Zone (ITCZ), driver of proto-monsoonal rainfall. Cooler temperatures in the late Eocene of central Myanmar may be due to the lack of adequate modern analogues for the Eocene monsoonal climate, while those found at other three Eocene Asian paleobotanical sites (India and South China) may be caused by the effect of canopy evapotranspirational cooling. Our data suggest that paleoenvironmental change including two transgressive-regressive depositional sequences is controlled by global sea level change, which may be driven by climate change and tectonics. The high diversity of the Yaw Formation palynoflora, despite well-marked seasonality, is explained by its cross-roads location for plant dispersals between India and Asia.

International audience; The development of field-effect transistor-based (FET-based) non-volatile optoelectronic memories is vital toward innovations necessary to improve computer systems. In this work, for the first time, the unique charge-trapping and charge-retention properties of solution-processed colloidal nitrogen-doped carbon quantum dots (CQDs) are harnessed to achieve functional optoelectronic memories programmable by UV illumination with a multilevel writing possibility. Of particular note, long-lasting memory function can be achieved thanks to the vast charge trapping sites provided by the N-doped CQDs and the resultant photo-gating effect is exercised on the graphene FET. The achieved memory can be erased by a positive gate bias which provides sufficient carriers to remove trapped charges through recombination. This study highlights the possibility to engineer high-performance all-carbon non-volatile FET-based optoelectronic memories through manipulating and coupling the charge-trapping properties of colloidal CQDs and graphene.

International audience; The development of high-performance and cost-effective hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalysts is highly required for electrochemical water splitting. The sluggish reaction kinetics, poor stability, and complicated processing restrict the practical application of most electrocatalysts. Herein, we report a facile oxygen corrosion strategy for the fabrication of Pt nanoparticles loaded on cobalt-iron layer double hydroxide (Pt-Co/Fe LDH) on iron foam using an oxygen corrosion method regulated by sodium chloride (NaCl). The as-prepared Pt-Co/Fe LDH electrodes feature overpotentials as low as 126 and 285 mV to deliver 100 mA cm–2 for HER and OER, respectively. Moreover, the Pt-Co/Fe LDH was applied as anode and cathode in an electrochemical electrolyzer and recorded a current density of 50 mA cm–2 at a small voltage of 1.66 V, which is superior to that of the Pt/C-FF || RuO2-FF system (1.89 V) and those of most previously reported electrocatalysts. The excellent electrocatalytic activity of Pt-Co/Fe LDH could be assigned to its specific structure, consisting of three-dimensional (3D) nanoflower-shaped nanosheets, favorable for promoting fast mass transport and ion diffusion and generating more active sites for the OER process. In addition, the synergistic effect between Pt and the Co/Fe LDH heterojunction structure effectively improves the electronic conductivity and H adsorption for HER performance. The oxygen corrosion method regulated by NaCl and interface engineering of the LDH structure is simple to implement and can be easily extended for the preparation of a plethora of other bifunctional and cost-effective electrocatalysts for various electrochemical processes.

Combination therapy, often referring to the administration of two or more therapeutic agents with different functional sites in cancer cells, has been used to address the efficacy of chemotherapy in clinical application. However, the clinical outcomes of conventional combination therapies with the cocktail mixture of multiple free drugs often suffers from unideal therapeutic outcomes due to the variations in drug properties such as different solubility, individual pharmacokinetic fate, as well as inconsistent tissue distribution and cell permeability. The work presented in this thesis aimed to promote the synergism of the therapeutics with carrier-free co-delivery nanoplatforms. To achieve this purpose, three different nano-delivery systems (nanoDDSs) were designed and fabricated with different combinations of anti-tumour therapeutic agents. Physicochemical characterisations and in vitro anti-tumour activity of each nanoDDS were performed to evaluate their suitability for the drug co-delivery to realise an augmentation in the anti-tumour efficacy. In the first part of this work, a self-assembled carrier-free nanoDDS was prepared with cisplatin (CDDP, an alkylating agent) and dactolisib (BEZ, a PI3K inhibitor). The suitable formulation process for the nanoDDS was firstly explored by the preparation with different drug ratios, from which a modified formulation was selected through the comparison of particle size and morphological features. The as-prepared nanoparticles, denoted as CDDP-BEZ nanoparticles (NPs), were uniform spheres with a dynamic diameter of 136.5 ± 0.7 nm. Based on the coordination bond between the hydrophilic CDDP and BEZ, the driving force for the formation of CDDP-BEZ NPs was majorly hydrophobic interaction and electrostatic interaction, which further led to a pH-responsive drug release profile. By simultaneously affecting DNA and inhibiting PI3K signalling axis, CDDP-BEZ NPs exhibited potent anti-proliferative effect on cancer cells. Besides, the increased lipophilicity due to the coordination with BEZ facilitated the accumulation of CDDP in mitochondrion, resulting in the activation of mitochondrion-dependent intrinsic apoptosis and subsequently leading to a further elevated synergistic efficacy in killing cancer cells. Additionally, CDDP-BEZ NPs successfully restraint the cell migration and invasion induced by chemo therapy. With a 3-dimensional (3D) tumour spheroid model, we further confirmed that CDDP-BEZ NPs maintained all the superiorities in combating tumour development and progression under complicated physiological condition. In the second part of this work, the feasibilities of addressing the negative insulin feedback by the co-administration of PI3K inhibitors with anti-hyperglycaemia agents were explored. To realise this goal, two nanoDDSs were designed and fabricated, one for the co-delivery of BEZ and glucose oxidase (GOx), and the other one of the co-delivery of BEZ and metformin. An albumin-based nanoDDS was prepared for the co-delivery of BEZ and GOx through the hydrophobic interaction-induced co-assembly of chemically modified BEZ (Lx-BEZ), GOx, and bovine serum albumin (BSA). For the modification of the formulation process, nanoparticles prepared with different ratios among BEZ, GOx, and BSA at various mixing time were compared in the aspect of particle size and morphology, from which a nanoDDS denoted as LBGB was selected. The as-prepared LBGB was uniform quasi-sphere with a diameter of around 70 nm, with preservation of the catalytic activity of GOx and a pH-responsive drug release profile of BEZ. Enhanced synergy between GOx and BEZ was observed with LBGB in cancer cells compared with the physical mixture of dual agents, even with the existence of insulin. Besides, LBGB exhibited a more potent restraint on the migration property of cancer cells compared with the mixed administration of GOx and BEZ. Consistent anti-tumour activity of LBGB was also observed on 3D tumour spheroids, indicating its excellent therapeutic efficacy even under complicated environment. For the co-delivery of BEZ and metformin, a nanoDDS based on Lx-BEZ and the polymeric prodrug of metformin (pMet) was proposed and established through the π-π stacking interaction. The modified formulation process was obtained by the screening of nanoparticle prepared with different ratios of Lx-BEZ and pMet at different mixing time, from which a suitable nanoDDS (pMet-LB) was selected by the comparison of particle size and morphology. Despite unsatisfactory pH-responsive drug release profile, pMet-LB exhibited excellent anti-tumour efficacy in 2-dimensional (2D) monolayer-cultured cancer cells, and maintained its potency in killing cancer cells with the presence of insulin. However, no superiority was observed in the anti-tumour activity from pMet-LB on the 3D tumour spheroids, likely due to its lack of pH-responsiveness. This failed intention emphasised the importance of using suitable 3D tumour models to better simulate the actual tumour microenvironment, through which an outcome better reflecting the real physiological process could be obtained. In the third part of this work, the feasibilities of establishing a nanoDDS for the steady delivery of Ca2+ and other anti-tumour therapeutic agents was explored. Both CaCO3- and CaO2-based nanoparticles were explored for this purpose, through which a CaO2-based nanoDDS modified with curcumin-grafted-hyaluronic acid and transferrin (CaO2@HC-Fe-Tf) was selected for further study. With excellent lyophilisation and serum stability, CaO2@HC-Fe-Tf was uniform sphere of around ~250 nm in diameter with a clear core-shell structure, holding the capacity to enter cancer cells, release H2O2, and initiate Ca2+ overloading, and resulting in its anti-cancer activity. Despite the relatively mild potency in killing cancer cells, CaO2@HC-Fe-Tf exhibited obvious suppression on the migration of cancer cells from the spheroid. Results from this experiment suggested that further combination with other therapeutic agents might be necessary for an ideal therapeutic outcome. Collectively, this work demonstrated that carrier-free co-delivery nanoDDSs represented a promising strategy in addressing the issues related with the combination therapy currently applied in clinical. With the precise delivery of both therapeutic agents into the same cell with minimum assistance of vector materials, the carrier-free co-delivery nanoDDSs implemented a way for anti-tumour agents with different targets to simultaneously exert their functions, thus achieving a facilitated anti-tumour efficacy. Through the design and fabrication of three nanoDDSs based on different combinations of therapeutic agents, this work explored the feasibility of building stable carrier-free co-delivery nanoDDSs via different strategies, while evaluating the potential of each nanoDDSs in the aspects of physicochemical properties such as particle size and morphology, as well as in vitro anti-tumour efficacy on 2D monolayer-cultured cells or 3D tumour spheroids. With the discrepancies observed between the results from 2D monolayer study and those from the 3D tumour spheroid study, this work also proposed the application of tumour spheroids as in vitro model in evaluating the therapeutic profile of the established nanoDDSs, which could better simulate the complicated in vivo environment for the actual pharmacokinetic evaluation. The results obtained from this work suggested that with proper design, the carrier-free co-delivery nanoDDS held the potential to serve as versatile platform, realising the simultaneous delivery of a wide range of anti-tumour agents including chemotherapeutics, enzymes, as well as inorganic substance. Apart from the augmentation in the anti-tumour efficacy, carrier-free co-delivery nanoDDS also provided a cost-friendly alterations, for there was a significant cut-down in the development lifecycle with the combination of two FDA-approved therapeutic agents. In addition, the recently emerged computational screening greatly accelerated the progress of the rational design of optimal combination, paving the way for the industrialisation of the carrier-free co-delivery nanoDDSs and the subsequent clinical translation. Collectively, the work presented in this thesis aimed to exploit the possibility of using carrier-free co-delivery nanoDDS to augment the therapeutic efficacy and minimise the vector-driven side effects in the anti-tumour combination therapies, exploring a potent and affordable way to benefit the cancer patients worldwide.

The visit of the President of Russia to China has always been a major event, attracting wide attention of mass media of the two countries. The article presents the results of the analysis of coverage of Vladimir Putin’s visit to China in February 2022 based on the material of the international TV channels RT and CGTN. The features of the coverage of this topic by two media are shown in terms of the number of messages and the tone of coverage., Визит Президента России в Китай — всегда крупное событие, привлекающее широкое внимание средств массовой информации двух стран. В статье представлены результаты анализа освещения визита Владимира Путина в Китай в феврале 2022 г. международными телеканалми RT и CGTN.

Plant nucleotide-binding and leucine-rich repeat domain proteins (NLRs) are immune sensors that recognize pathogen effectors. Here, we show that molecular engineering of the integrated decoy domain (ID) of an NLR can extend its recognition spectrum to a new effector. We relied for this on detailed knowledge on the recognition of the Magnaporthe oryzae effectors AVR-PikD, AVR-Pia, and AVR1-CO39 by, respectively, the rice NLRs Pikp-1 and RGA5. Both receptors detect their effectors through physical binding to their HMA (Heavy Metal-Associated) IDs. By introducing into RGA5_HMA the AVR-PikD binding residues of Pikp-1_HMA, we create a high-affinity binding surface for this effector. RGA5 variants carrying this engineered binding surface perceive the new ligand, AVR-PikD, and still recognize AVR-Pia and AVR1-CO39 in the model plant N. benthamiana. However, they do not confer extended disease resistance specificity against M. oryzae in transgenic rice plants. Altogether, our study provides a proof of concept for the design of new effector recognition specificities in NLRs through molecular engineering of IDs.

Nowadays, the energy and environment have become the restrictions to the development of human society. To solve the crisis coming from energy and environment, nanoparticles play a dominant role as the catalysts. However, traditional catalysts are easy to agglomerate to decrease their properties under high working temperatures. As a promising method to prepare nanoparticles, a new strategy, called exsolution, was proposed and has obtained much attention in many fields in catalysis and energy conversion and storage field due to the nanoparticles with the well-anchored and strained socketed structure. This thesis illustrates the fundamental properties by doping different transition metals into the B-site of the perovskite. The parameters of the unit cells matched very well with the ionic radii of dopants. The corresponding nanoparticles exsolved successfully after the reduction post-treatments. In particular, the thesis demonstrates the effects of reducing temperature and holding time on exsolution. In the exploration of the behaviours of exsolved nanoparticles after the redox experiments, it was found that the population and size of nanoparticles exsolved at lower temperatures were more sensitive than those exsolved at high temperatures. The evolution of nanoparticles with different ratio of Ni and Co after CO oxidation experiments with different CO partial pressure was explored. As the loading of Co increases, the shape of the nanoparticles oxidized in CO oxidation experiments transformed from spherical to cubic, while the elemental distribution was still homogenous. The thesis also explores the exsolution of small-sized metallic Cu nanoparticles from single-phase perovskite. We show that this is possible by selecting the suitable Cu precursor and control the parameters of the preparation to achieve Cu exsolution and its practical utility by preparing a nanostructured Cu metal catalyst which rival conventionally prepared Cu-based samples applied for CO oxidation. The catalytic properties of perovskite with exsolved nanoparticles can be tailored by doping Fe and Zn due to the synergistic effect.

redacted "This work was supported by the University of St Andrews and the China Scholarship Council (File No. 201708060005). This work was impacted by the COVID-19 pandemic, a 6-month extension was granted and was supported by the University of St Andrews and the Royal Society of Chemistry (RSC)." -- Acknowledgements

Common ground is seen as the basis for human communication and cooperation. Within common ground research, the main focus has always been on the knowledge that partners know together, i.e., "common knowledge". However, this neglects the factor of ignorance, which must be considered to be an integral component of common ground. To fill in this gap, different aspects of common ground (common knowledge, common ignorance, common privileged knowledge/ignorance) were investigated with a new coordination game in children between 4 and 8 years old. Results showed that common ignorance and common privileged ignorance were more difficult than common knowledge and common privileged knowledge: It was only by age 6 that children could use common ignorance at an equivalent level with common knowledge, and they had difficulty with “common privileged other knowledge” (i.e. self ignorance) even until age 8. Children’s understanding of ignorance was further probed with a preliminary investigation of strategic ignorance in children. As young as 4 years of age, children reported that they could actively choose not to know something, and from 5 years of age, adult-like reasons were given for things they preferred not to know. Common ground goes beyond common knowledge and ignorance states, and can also involve a feeling of co-presence. Whether physical co-presence in video calls could be simulated by partners using the same virtual background was investigated in an online study of adults. Results showed that using the same, as opposed to a different, background in video calls could enhance partners’ feelings of connectedness to some extent: They used a higher proportion of “we” pronouns, though they did not show a difference on other measurements such as perspective taking or mimicry. Taken together, this thesis contributes new knowledge about neglected aspects of common ground: the importance of common ignorance and its interplay with common knowledge in development, and the importance of markers of co-presence in the shared experience of online social interactions.

The reactivity of 1,2-dihalobenzenes in palladium-catalyzed C–H bond functionalization is more difficult to control than that of 1,3- and 1,4-dihalobenzenes because of a possible Pd 1,4-migration during the second catalytic cycle. With C3-substituted heteroarenes this 1,4-palladium migration is not possible and the reaction allows the synthesis of a wide variety of functionalized 1,2-heteroarylated benzene derivatives in high yields. Conversely, only a few heteroarenes with a free C3 position, such as thiazoles, furans and imidazoles, allow the preparation of 1,2-heteroarylated benzenes. Despite these limitations, this one-pot procedure employing an easily available catalyst [Pd(OAc)2] and an inexpensive base (KOAc) provides a very simple method for the preparation of several 1,2-heteroarylated benzenes.

This project explores selected crystals with novel morphologies and corresponding growth mechanisms. Crystal samples from different growth stages are obtained by interrupting the reaction in order to study the growth mechanisms step by step. To achieve the characterisations of the crystals, electron microscopes and in-built electron spectroscopic techniques are the major implements. Together with electron microscopy, other techniques, such as X-ray diffraction and infrared spectroscopy, are also employed. Schematic visualisation is exploited to illustrate the formation mechanisms. Copper pseudo-icosahedral crystals are prepared and studied. Polyvinylpyrrolidone-assisted growth route involving dual-step reduction and multiple intermediate phases is revealed. The attribute of pseudo-icosahedral is discussed morphologically. Using the same synthesis system but different reactant, Cu₂O spherulites are prepared. By examining the polarity of the spherulites and the feature of Cu₂O nanocrystallites in PVP matrix, the formation mechanism concerning intrinsic dipolar force is proposed. Cs₄PbBr₆ rhombohedral crystals with embedded CsPbBr₃ nanocrystallites are produced via antisolvent preparation method. Despite the sensitivity to electron beam exposure, we manage to visualise the material using electron microscopy. With observed evidence of amorphous precursor, a formation mechanism associated with the precursor amorphous phase is proposed. Different antisolvents are tested on their effects of the morphology. Water triggered transformation of Cs₄PbBr₆ to CsPb₂Br₅ and CsPbBr₃ is realised. Electron microscopic and spectroscopic information of Ti₃C₂Tₓ nanowire clusters synthesised at Beijing Normal University reveals the dimensional degradation mechanism. From the oxidation of layered Ti3C2Tₓ structure, interconnected Ti₃C₂O and Ti₃C₂ nanowires are produced. We anticipate that this doctorate project can provide new perspectives in understanding non-classical crystal growth, set an example for the study of beam sensitive materials and inspire the morphology engineering of crystalline materials.

International audience; In the continuation of our sustained interest for porphyrin-based dendrimers and their use as luminescent photo-sensitizers for two-photon photodynamic therapy (2P-PDT), we wondered about the effect of changing the central porphyrin core for a phthalocyanine core in these macromolecular structures. Thus, related phthalocyanine-based dendrimers possessing up to 16 conjugated 9,9-dibutyl-2-fluorenyl endgroups at their periphery were now prepared and studied. As for porphyrin analogues, it was found that an efficient energy transfer occurs from the peripheral fluorenyl units toward the central phthalocyanine unit of these compounds, leading to intense red light emission and photosensitization of oxygen. While the linear optical properties of these new dendrimers are only slightly improved compared to those of their porphyrin-cored analogues for PDT and fluorescence imaging, their two-photon absorption (2PA) cross-sections are much more significantly boosted, evidencing the key role played by the central tetrapyrrolic unit in this respect. The impact of this structural change in relation with the impact resulting from the change in dendrimer generations is then discussed with the help of DFT and molecular dynamic calculations.

The specific recognition of pathogen effectors by intracellular nucleotide-binding domain and leucine-rich repeat receptors (NLRs) is an important component of plant immunity. NLRs have a conserved modular architecture and can be subdivided according to their signaling domain that is mostly a coiled-coil (CC) or a Toll/Interleukin1 receptor (TIR) domain into CNLs and TNLs. Single NLR proteins are often sufficient for both effector recognition and immune activation. However, sometimes, they act in pairs, where two different NLRs are required for disease resistance. Functional studies have revealed that in these cases one NLR of the pair acts as a sensor (sNLR) and one as a helper (hNLR). The genes corresponding to such resistance protein pairs with one-to-one functional co-dependence are clustered, generally with a head-to-head orientation and shared promoter sequences. sNLRs in such functional NLR pairs have additional, non-canonical and highly diverse domains integrated in their conserved modular architecture, which are thought to act as decoys to trap effectors. Recent structure–function studies on the Arabidopsis thaliana TNL pair RRS1/RPS4 and on the rice CNL pairs RGA4/RGA5 and Pik-1/Pik-2 are unraveling how such protein pairs function together. Focusing on these model NLR pairs and other recent examples, this review highlights the distinctive features of NLR pairs and their various fascinating mode of action in pathogen effector perception. We also discuss how these findings on NLR pairs pave the way toward improved plant disease resistance.

International audience; We report a rh(I)-catalyzed C-H bond alkylation of PhenCarPhos [= N-(2-(diphenylphosphaneyl)phenyl)carbazole] and some congener phosphine ligands with alkenes. The C-H bond functionalization occurred exclusively at the C1 position of the carbazolyl unit because the trivalent phosphine acts as a directed group. This protocol provides straightforward access to a large library of C1-alkyl substituted PhenCarPhos, which outperformed common commercial or unfunctionalized phosphines and their precursors in the Pd-catalyzed carbon dioxide-fixation reactions with propargylic amines. Designing more active ligands is one of the most important fields of catalysis and organometallic chemistry. Despite numerous advances in transition metal-catalyzed reactions, developing efficient catalytic systems is still highly desirable for industrial application, significantly decreasing their environmental impact. Among the different classes of ligands, phosphines remain the most popular with several well-established industrial processes. 1 It is admitted that the associated phosphines can modulate the activity of metal centers of catalysts through fine-tuning of their steric and electronic properties or by weak interactions in the second coordination sphere. However, the synthesis of such multifunctional phosphines with different substituents often requires multistep synthesis and the use of organometallic reagents may limit the diversity of the functional group that can be introduced in the phosphine scaffold. Since the pioneer observation by Hartwig and co-workers on Pd-catalyzed direct polyarylation of 1-(di-tert-butylphosphino)ferrocene, 2 P(III)-chelation-assisted C-H bond functionalization has become a straightforward strategy to

International audience; Many gene regulatory networks have periodic behavior, for instance the cell cycle or the circadian clock. Therefore, the study of formal methods to analyze limit cycles in mathematical models of gene regulatory networks is of interest. In this work, we study a pre-existing hybrid modeling framework (HGRN) which extends René Thomas' widespread discrete modeling. We propose a new formal method to nd all limit cycles that are simple and deterministic, and analyze their stability, that is, the ability of the model to converge back to the cycle after a small perturbation. Up to now, only limit cycles in two dimensions (with two genes) have been studied; our work lls this gap by proposing a generic approach applicable in higher dimensions. For this, the hybrid states are abstracted to consider only their borders, in order to enumerate all simple abstract cycles containing possible concrete trajectories. Then, a Poincaré map is used, based on the notion of transition matrix of the concrete continuous dynamics inside these abstract paths. We successfully applied this method on existing models: three HGRNs of negative feedback loops with 3 components, and a HGRN of the cell cycle with 5 components.

International audience; High energy consumption during harvesting is one of the main bottlenecks for sustainable microalgae production. Membranes can efficiently separate microalgae from liquids with low energy consumption, but membrane fouling remains an important issue. Flocculation prior to membrane filtration can increase membrane fluxes and decrease fouling, thus offering a low-cost and efficient solution to harvest microalgae. Biobased cationic cellulose nanocrystals were successfully used as flocculants for microalgae and were effective over a wide pH-range and for both freshwater and marine microalgae. Such flocculation was for the first time combined with vibration-assisted filtration using a charged, surface patterned membrane, enabling operation at very high flux (95 L/m2 h) using a vibration frequency of only 1 Hz, and even under sub-optimal flocculation conditions. Intermittent vibration decreased energy consumption further while keeping excellent filtration performance to finally achieve a record-low energy consumption for the membrane filtration of only 6.7 Wh/m3, which is andgt;25-times lower than that of normal membrane filtration. Interaction forces revealed that increasing particle size through flocculation prior to membrane filtration can significantly prevent microalgae attachment on the vibrating membrane surface. This work opens a new direction for sustainable microalgae harvesting with an ultra-low energy consumption, combined with a very high microalgae recovery, reduced use of chemicals, and lower membrane investment cost.

In this work, high-speed drop impact onto deep volume of the same liquid is numerically studied in 3D using Direct Numerical Simulation (DNS). The numerical results are compared with the previous experimental works by Murphy et al. [1]. Most of the distinctive features during the impact, including the evolution of the crown and cavity, the ligaments emanating from the rim of the crown, the formation of the bubble canopy, the central spiral jet that pierces through the bottom of the cavity and the subsequent broad upward jet, are correctly reproduced. The trajectory of the upper rim of the crown as well as the depth and width of the subsurface cavity are tracked during the simulation. Very reliable quantitative agreements between numerical and experimental data are obtained with respect to the time evolution of the crown rim and cavity dimensions. The simulation shows very good qualitative and quantitative agreement against the available experimental data, which enables the further investigation of the internal mechanisms of drop impact in the future This work has been supported by the scholarship from China Scholarship Council (CSC) under the Grant CSC NO. 201908320462.

International audience; Purpose: Computed tomography (CT) has the advantages of being low cost and noninvasive and is a primary diagnostic method for brain diseases. However, it is a challenge for junior radiologists to diagnose CT images accurately and comprehensively. It is necessary to build a system that can help doctors diagnose and provide an explanation of the predictions. Despite the success of deep learning algorithms in the field of medical image analysis, the task of brain disease classification still faces challenges: Researchers lack attention to complex manual labeling requirements and the incompleteness of prediction explanations. More importantly, most studies only measure the performance of the algorithm, but do not measure the effectiveness of the algorithm in the actual diagnosis of doctors. Methods: In this paper, we propose a model called DrCT2 that can detect brain diseases without using image-level labels and provide a more comprehensive explanation at both the slice and sequence levels. This model achieves reliable performance by imitating human expert reading habits: targeted scaling of primary images from the full slice scans and observation of suspicious lesions for diagnosis. We evaluated our model on two open-access data sets: CQ500 and the RSNA Intracranial Hemorrhage Detection Challenge. In addition, we defined three tasks to comprehensively evaluate model interpretability by measuring whether the algorithm can select key images with lesions. To verify the algorithm from the perspective of practical application, three junior radiologists were invited to participate in the experiments, comparing the effects before and after human-computer cooperation in different aspects. Results: The method achieved F1-scores of 0.9370 on CQ500 and 0.8700 on the RSNA data set. The results show that our model has good interpretability under the premise of good performance. Human radiologist evaluation experiments have proven that our model can effectively improve the accuracy of the diagnosis and improve efficiency. Conclusions: We proposed a model that can simultaneously detect multiple brain diseases.The report generated by the model can assist doctors in avoiding missed diagnoses, and it has good clinical application value.

International audience; Computed tomography (CT) is the primary diagnostic tool for brain diseases. To determine the appropriate treatment plan, it is necessary to ascertain the patient's bleeding volume. Automatic segmentation algorithms for hemorrhagic lesions can significantly improve efficiency and avoid treatment delays. However, for deep supervised learning algorithms, a large amount of labeled training data is usually required, making them difficult to apply clinically. In this study, we propose an unsupervised domain adaptation method that is an unsupervised domain adaptation segmentation model that can be trained across modalities and diseases. We call it AMD-DAS for brain CT hemorrhage segmentation tasks. This circumvents the heavy data labeling task by converting the source domain data (MRI with glioma) to our task's required data (CT with Intraparenchymal hemorrhage (IPH)). Our model implements a two-stage domain adaptation process to achieve this objective. In the first stage, we train a pseudo-CT image synthesis network using the CycleGAN architecture through a matching mechanism and domain adaptation approach. In the second stage, we use the model trained in the first stage to synthesize the pseudo-CT images. We use the pseudo-CT with source domain labels and real CT images to train a domain-adaptation segmentation model. Our method exhibits a better performance than the basic one-stage domain adaptation segmentation method (+11.55 Dice score) and achieves an 86.93 Dice score in the IPH unsupervised segmentation task. Our model can be trained without using a ground-truth label, therefore increasing its application potential. Our implementation is publicly available at https://github.com/GuanghuiFU/AMD-DAS-Brain-CT-Segmentation.

International audience; This study aims at investigating the lime treatment effect on the changes in microstructure and water retention property of compacted saline soil, with consideration of the aggregate size effect. Two soil powders with different maximum aggregate sizes (Dmax = 0.4 and 5 mm) were prepared and stabilized by 2% lime. The microstructure, total suction and matric suction were determined at various curing times. Results showed that the lime treatment caused a rapid decrease in micro-pores and an increase in macro-pores due to the flocculation of soil particles. During curing, the percentage of micro-pores decreased and that of nano-pores increased slightly. Due to the modification of microstructure, the matric suction increased significantly at 90-day curing. However, the curing time effect on the total suction was insignificant. This was due to the fact that the Ca2+ and Mg2+ in soil pore water and the Ca2+ from hydrated lime were consumed in the precipitations of CaCO3 and Mg(OH)2, cation exchanges and pozzolanic reaction, resulting in a reduction in osmotic suction. Therefore, the increase in total suction was slight, as the increase in matric suction was balanced by the decrease in osmotic suction. The treated specimens with larger aggregates exhibited a larger modal size and thus had a smaller air entry value. The aggregate size effect on the water retention property of total suction and matric suction was found to be insignificant, which could be explained by the similar pore size distribution at micro-pore range and the same soil mineralogy for specimens with different aggregates.

International audience; Determination of forming limit curve (FLC) over a wide range of strain paths can provide a more thorough understanding of sheet metal formability. In this work, for the first time, in-plane biaxial tensile tests employing two distinct cruciform specimens are performed to construct the FLC of AA6061-T4 sheets from shear to equi-biaxial stretching. Four different necking detection methods are investigated in a FE (finite element) procedure to find proper ones for the defined specimens. This procedure consists of the FE modeling of the biaxial tensile test and the Marciniak test. An anisotropic Gurson-Tvergaard-Needleman (GTN) plasticity model based on Hill'48 yield function is calibrated and implemented in simulations to reproduce the anisotropic plasticity and failure behavior of AA6061-T4 sheets. Then, the selected necking detection methods are applied to the biaxial tensile test to experimentally identify the limit strains at necking. The results show that considering two distinct cruciform specimens is an effective solution for the biaxial tensile test to determine the FLC covering a wider range of strain paths. The predicted FLCs show good agreement with the experiments, indicating that the numerical biaxial tensile test combined with the anisotropic GTN plasticity model is an efficient tool for predicting sheet metal formability. © 2023 Elsevier Ltd

International audience; In deep-sea slope areas, canyons provide an ideal space to preserve sediments and provide a window to explore the deepwater deposition process, such as turbidity flow and contourite currents. We have evaluated results of the study of the northern continental slope of the South China Sea characterized by the presence of mostly straight canyons. After evaluating core samples and interpreting the corresponding seismic data, we static the sedimentary parameter and identified two types of canyons with different migrating trajectories: "convex downward curve-shaped" trajectories and "convex upward curve-shaped" trajectories. The convex downward curve-shaped canyon trajectory is distinguished by a lower layer of coarse-grained sediment and an upper layer of fine-grained sediment, whereas the convex upward curve-shaped canyon trajectory features a lower layer of fine-grained sediment and an upper layer of coarse-grained sediment. Combining the grain size of the core sample and the scale of the sedimentary structure, we restore the turbidity flow rates and the corresponding turbidity flow behaviors. Coarse-grained turbidity flows are characterized by lower vertical erosion rates and higher lateral abrasion rates, whereas fine-grained turbidity flows exhibit the opposite characteristics. Thus, the convex downward curve-shaped migration trajectory is mainly formed by coarse-grained turbidity flow erosion in the first stage (the late migration stage) and fine-grained turbidity flow deposition in the second stage (the vertical aggradation stage). In contrast, the convex upward curve-shaped trajectory forms through the opposite pattern of sedimentary evolution.

International audience; We study the assembly kinetics of surfactant-stabilized gold nanoparticles in the presence of sulfate ions. The reaction proceeds in two steps: very rapid (a few minutes) formation of amorphous aggregates, followed by slow reordering (over several hours). The latter process is the only one detectable via absorbance spectroscopy and results in the formation of intimate contacts between the objects, with interparticle distances below the thickness of a surfactant bilayer. The rate-limiting step of the reaction could be related to surfactant expulsion from the initial aggregates, which allows the particles to come in close contact and form chains. There are marked differences in reaction yield and rate constant between spheres, rods and bipyramids, highlighting the role of surface curvature in contact formation. Once formed, the assemblies are very sturdy and stable under centrifugation and dialysis. The contact interaction is strong and highly directional, as shown by liquid-cell transmission electron microscopy.

WOS:000600550100030; International audience; Chromium (Cr) isotopes play an important role in cosmochemistry and planetary science because they are powerful tools for dating (Mn-53-Cr-53 short-lived chronometry), tracing (Cr-54 nucleosynthetic anomalies) the origins of the materials, and studying the processes involved in volatile element fractionation and planetary differentiation (Cr stable isotopic fractionation). To use Cr isotopes for these purposes, it is essential to precisely know the compositions of the various chondritic reservoirs. However, the Cr isotope composition of Rumuruti (R) chondrites remains unknown. Here, we report high-precision mass-independent (average 2SE uncertainty of similar to 0.02 and similar to 0.06 for epsilon Cr-53 and epsilon Cr-54, respectively; epsilon indicates 10,000 deviation) and mass-dependent (uncertainty of average 0.03 parts per thousand for delta Cr-53; .delta indicates 1000 deviation) Cr isotope data for 12 bulk R chondrites of petrologic types 3-6 (including R chondrite breccias), and one R chondrite-like clast (MS-CH) in the Almahata Sitta polymict ureilite. All the R chondrites show homogeneous bulk epsilon Cr-54 values, -0.06 +/- 0.08 (2SD), similar only to those of the Earth-Moon system and enstatite chondrites. This first epsilon Cr-54 dataset for R chondrites provides significant addition to the epsilon Cr-54-A, Delta O-17 diagram, and positions them as a potential endmember for planetary precursors. The R chondrites possess a higher Mn-55/Cr-52 of 0.68 +/- 0.04 relative to most of carbonaceous chondrites and higher epsilon Cr-53 values 0.23 +/- 0.05 (2SD) relative to most of chondrite groups. This likely results from the lower chondrule abundance in R chondrites compared to that of ordinary and enstatite chondrites. The stable Cr isotope composition of R chondrites is homogeneous with a delta Cr-53 = -0.12 +/- 0.03%e (2SD). Combined with previous data of other groups of chondrites, we show that the stable Cr isotopic composition of all the chondrites is homogeneous with delta Cr-53 of -0.12 +/- 0.04%e (2SD, N = 42) and is independent of the petrologic type and redox conditions. The lack of mass-dependent fractionation between all groups of chondrites suggests that the average chondrite delta Cr-53 value is also representative for the initial composition of all differentiated planets in the Solar System. Finally, the MS-CH clast in Almahata Sitta has a Cr isotopic composition (epsilon Cr-53 = 0.18 +/- 0.04, epsilon Cr-54 = 0.16 +/- 0.07, and delta Cr-53 = -0.11 +/- 0.05%e) that is consistent (within error) with it being an R chondrite-like clast. (C) 2020 Elsevier Ltd. All rights reserved.

International audience; In this work, we give a complete characterization of the epsilon-stable region in dynamic downlink random cellular networks. The epsilon-stable region is the set of arrival rates such that the proportion of unstable queues in the network is not larger than epsilon. We derive upper and lower bounds as well as an approximation of the critical arrival rate, which delimits the epsilon-stable region. The developed model is based on stochastic geometry and queuing theory to handle the interaction between the transmit success probability and the queuing state evolution. Extensive numerical simulations are provided to confirm the tightness of the approximation.