bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooperation in public goods experiments with random and finite stopping rules
Authors: Anderson Lisa R. , Hicks Robert L. , Turscak Andrew
Published: March 2024

We contribute to a large literature that explores prosocial behavior in public goods experiments. We adopt an experimental design that allows full contribution to the public good to be sustained in equilibrium. We study the effect of the time horizon on a subject's propensity to contribute to a public good by varying the stopping rule for the game. While many studies examine the effect of a random stopping rule in prisoner's dilemma games, to our knowledge, only two other studies have directly compared behavior in public goods experiments with finite and random stopping rules. Consistent with existing studies, we find that contribution rates are similar across treatments in early rounds of play, and contribution rates are higher with random verses finite stopping rules in later rounds. Overall, we find significantly higher contributions to the public good when donors face a known probability of future interactions with the same group of participants compared to interactions with a finite endpoint. Further, the difference in cooperative behavior is driven primarily by the stopping rule, rather than the length of the game.
An extension of the best–worst method based on the spherical fuzzy sets for multi-criteria decision-making
Authors: Haseli Gholamreza , Sheikh Reza , Ghoushchi Saeid Jafarzadeh , Hajiaghaei-Keshteli Mostafa , Moslem Sarbast , Deveci Muhammet , Kadry Seifedine
Published: March 2024

The ambiguous information in multi-criteria decision-making (MCDM) and the vagueness of decision-makers for qualitative judgments necessitate accurate tools to overcome uncertainties and generate reliable solutions. As one of the latest and most powerful MCDM methods for obtaining criteria weight, the best–worst method (BWM) has been developed. Compared to other MCDM methods, such as the analytic hierarchy process, the BWM requires fewer pairwise comparisons and produces more consistent results. Consequently, the main objective of this study is to develop an extension of BWM using spherical fuzzy sets (SFS) to address MCDM problems under uncertain conditions. Hesitancy, non-membership, and membership degrees are three-dimensional functions included in the SFS. The presence of three defined degrees allows decision-makers to express their judgments more accurately. An optimization model based on nonlinear constraints is used to determine optimal spherical fuzzy weight coefficients (SF-BWM). Additionally, a consistency ratio is proposed for the SF-BWM to assess the reliability of the proposed method in comparison to other versions of BWM. SF-BWM is examined using two numerical decision-making problems. The results show that the proposed method based on the SF-BWM provided the criteria weights with the same priority as the BWM and fuzzy BWM. However, there are differences in the criteria weight values based on the SF-BWM that indicate the accuracy and reliability of the obtained results. The main advantage of using SF-BWM is providing a better consistency ratio. Based on the comparative analysis, the consistency ratio obtained for SF-BWM is threefold better than the BWM and fuzzy BWM methods, which leads to more accurate results than BWM and fuzzy BWM.
Nutritional value and functional properties of an underexploited Tunisian wild beet (Beta macrocarpa Guss.) in relation to soil characteristics
Authors: Mahmoud K. Ben , Abdelkefi F. , Mezzapesa G. N. , Perrino E. V.
Published: March 2024

The study centers on the valorization of Beta macrocarpa Guss., an endangered Mediterranean wild plant that grows in Tunisia. This plant is disappearing due to a reduction in marginal areas and a lack of awareness of this important crop wild relative (CWR). This prompted us to carry out work to assess the nutritional and functional value of its plant shoots in relation to physicochemical soil properties at three different Tunisian sites covering the north (Sijoumi), the center (Enfidha) and the south (Kerkennah) of the country. All soil samples showed an alkaline pH and high salinity. Sijoumi, Enfidha and Kerkennah soils were classified as loamy, silty clay loamy and sandy, respectively. Chemical analysis revealed that all soils, especially the sandy one, were low in total nitrogen, organic matter and microelements. Plant analysis showed that shoots harvested from the loamy soil presented the highest levels of carbohydrate (19.1 g/100 g FW) and fiber (6.1 g/100 g FW) and the greatest energetic value (94 kcal/100 g FW), whereas shoots collected from the sandy soil showed the highest contents of protein (4.1 g/100 g FW), ash (5.2 g/100 g FW), total polyphenols and flavonoids (39.01 mg GAE/g DW; 27.8 mg CE/g DW), and the greatest DPPH scavenging capacity (IC50 = 0.74 mg/ml). The results suggest that Beta macrocarpa, which naturally grows in poor and salt-affected soils, could play a crucial role in maintaining the biodiversity and sustainability of agro-ecosystems, particularly in marginal areas, and could also provide an alternative source of food with significant nutritional value and health benefits.

Graphical abstract
Learning deep news sentiment representations for macro-finance
Authors: Groß-Klußmann Axel
Published: March 2024

This paper introduces custom neural network techniques to the problem of latent economic factor extraction for voluminous news analytics data. In the context of macro-financial news, we derive low-dimensional representations of time series that arise in textual sentiment analyses spanning various topics. We explore three applications for compressed news sentiment data: nowcasting GDP growth, explaining asset class returns in a panel data analysis, and time series momentum investment. Our empirical study shows that nonlinear data representations based on supervised autoencoder architectures compare favorably to alternatives across all applications. In specific, we demonstrate that augmenting autoencoders with supervision tasks based on common asset class returns and market characteristics disciplines the dimension reduction and naturally supports the transparency of resulting representations. Taken together, our findings position supervised autoencoders as attractive competitor models alongside PCA and PLS approaches.
Governing Sea Level Rise in a Polycentric System
Authors: Vantaggiato Francesca Pia , Lubell Mark
Published: March 2024

How do polycentric governance systems respond to new collective action problems? This Element tackles this question by studying the governance of adaptation to sea level rise in the San Francisco Bay Area of California. Like climate mitigation, climate adaptation has public good characteristics and therefore poses collective action problems of coordination and cooperation. The Element brings together the literature on adaptation planning with the Ecology of Games framework, a theory of polycentricity combining rational choice institutionalism with social network theory, to investigate how policy actors address the collective action problems of climate adaptation: the key barriers to coordination they perceive, the collaborative relationships they form, and their assessment of the quality of the cooperation process in the policy forums they attend. Using both qualitative and quantitative data and analysis, the Element finds that polycentric governance systems can address coordination problems by fostering the emergence of leaders who reduce transaction and information costs. Polycentric systems, however, struggle to address issues of inequality and redistribution.
EONS: A New Biogeochemical Model of Earth's Oxygen, Carbon, Phosphorus, and Nitrogen Systems From the Archean to the Present
Authors: Horne J. E. , Goldblatt C.
Published: March 2024

We present Earth's Oxygenation and Natural Systematics (EONS): a new, fully coupled biogeochemical model of the atmosphere, ocean, and their interactions with the geosphere, which can reproduce major features of Earth's evolution following the origin of life to the present day. The model, consisting of 257 unique fluxes between 96 unique chemical reservoirs, includes an interactive biosphere, cycles of carbon, nitrogen, phosphorus, and oxygen, and climate. A nominal model run initialized in the Eoarchean resolves emergent surface oxygenation, nutrient limitations, and climate feedbacks. The modeled atmosphere oxygenates in stepwise fashion over the course of the Proterozoic; a nearly billion year lag after the evolution of photosynthesis at 3.5 Ga is followed by a great oxidation event at 2.4 Ga, which appears to be caused by the gradual buildup of organic matter on the continents imposing nutrient limitation on the biosphere by removing key nutrients from the ocean system. The simple climate system shows significant temperature shifts punctuate the oxygenation process, implying that major biological transitions possibly destabilized Earth's climate. This work demonstrates that forward modeling the entirety of Earth's history with relatively few imposed boundary forcings is feasible, that the Earth system is not at steady state, and that our understanding of coupled C‐N‐P‐O cycling as it functions today can explain much of the Earth's evolution.
On the Wave‐Normal Distribution of Lightning‐Generated Whistlers and Their Propagation Modes
Authors: Xia Zhiyang , Chen Lunjin , Horne Richard B. , Liu Xu , He Jiabei , Bortnik Jacob
Published: March 2024

Observations from Van Allen Probes are analyzed to obtain the statistical wave normal distribution of lightning‐generated whistlers (LGWs). An automatic algorithm is developed to identify burst mode waveform data with LGW signals and analyze the wave polarization information for these LGW signals. The spatial distribution of the LGW occurrence and the probabilities of different propagation types demonstrate that most LGWs can be observed in the low L‐shell region (L < 3), where the dominant propagation type is oblique outward. Parallel propagation dominates in the high L‐shell region, but the LGW occurrence is very small. Additionally, a small group of oblique but inwardly propagating LGWs are observed at low altitudes (<0.2RE). A ray tracing simulation is performed not only to confirm predominant oblique and outward wave vectors in the vast region of the plasmasphere but also to verify the existence of these inward propagating LGW signals at low altitudes near the topside ionosphere.
The Lithosphere and Upper Mantle of the Western‐Central Mediterranean Region From Integrated Geophysical‐Geochemical Modeling
Authors: Zhang Wentao , Jiménez‐Munt Ivone , Torne Montserrat , Vergés Jaume , Bravo‐Gutiérrez Estefanía , Negredo Ana M. , García‐Castellanos Daniel
Published: March 2024

This study integrates geophysical‐geochemical data to investigate the thermochemical structure of the lithosphere and sublithospheric mantle, along the Southern Tyrrhenian Basin, Apennines, Adriatic Sea, Dinarides, and Carpathians‐Balkanides. We present the lithospheric structure of the Adria microplate and the two opposing mantle slabs along its NE and SW margins. The modeling shows the presence of two asthenospheric mantle wedges aligning with the Apenninic and Dinaric continental mantle slab rollback, along with cold (−200°C) sublithospheric anomalies beneath Adria's NE and SW margins. In the northern Adria region, the lithosphere undergoes synchronous thinning in the Tyrrhenian domain and thickening toward the forefront of the northern Apennines. This is associated with the northeastward rollback of the SW Adriatic slab, leading to subsequent delamination of the continental mantle. In the southern Adria region, the complex deep structure results from the variably oriented lithospheric slabs, and nearly 90‐degree shift of the tectonic grain between the southern Apennines and the Calabrian Arc. At the SW Adria margin, beneath the northern Apennines, the thermal sublithospheric anomaly is attached to the shallower lithosphere, while a slab gap is modeled in the southern Apennines. One possibility is that the gap is due to a recent horizontal slab tear. Along the NE margin of Adria, the thermal anomaly penetrates to depths of about 200 km in the northern Dinarides and 280 km in the southern Dinarides, shallower than the SW Adria anomaly, which extends to at least 400 km depth.
Spatiotemporal Variability of Extreme Precipitation Events and Associated Atmospheric Processes Over Dronning Maud Land, East Antarctica
Authors: Simon Sibin , Turner John , Thamban Meloth , Wille Jonathan D. , Deb Pranab
Published: March 2024

We investigate the spatial and temporal variability of extreme precipitation events (EPEs) in the Dronning Maud Land (DML) sector of Antarctica using high‐resolution ECMWF ERA5 reanalysis data. This study examines the spatial occurrence of EPEs across DML, focusing particularly on six locations spanning the coastal and interior parts of the area. The largest snowfall amounts are usually found on eastward‐facing slopes in the coastal zone. EPEs occur predominantly in north‐easterly to easterly flows, leading to enhanced precipitation on the windward side of the orographic features with a steep gradient. Wind during EPEs was found to be more directionally consistent in the coastal area than in the interior. An east‐west couplet of a mid‐tropospheric ridge and low‐pressure center is essential for steering warm moist maritime airmasses into the DML region before EPEs. Approximately 40% of EPEs result from atmospheric rivers (ARs), narrow bands of moist air originating at subtropical latitudes, which provide the greatest daily precipitation amounts. From 1979 to 2018, much of the DML experienced a statistically significant (p < 0.05) increase in the number of EPEs per year, along with increased precipitation from the EPEs. These trends were associated with significant changes in moisture availability and poleward meridional winds in the Atlantic sector of the Southern Ocean. The inter‐annual variability in the number of EPEs is primarily dictated by regional atmospheric variability, while the influence of the Southern Oscillation Index and Southern Annular Mode is limited.
Observational Quantification of Tropical High Cloud Changes and Feedbacks
Authors: Raghuraman Shiv Priyam , Medeiros Brian , Gettelman Andrew
Published: March 2024

The response of tropical high clouds to surface warming and their radiative feedbacks are uncertain. For example, it is uncertain whether their coverage will contract or expand in response to surface warming and whether such changes entail a stabilizing radiative feedback (iris feedback) or a neutral feedback. Global satellite observations with passive and active remote sensing capabilities over the last two decades can now be used to address such effects that were previously observationally limited. Using these observations, we show that the vertically averaged coverage exhibits no significant contraction or expansion. However, we find a reduction in coverage at the altitude where high clouds peak and are particularly radiatively‐relevant. This results in a negative longwave (LW) feedback and a positive shortwave (SW) feedback which cancel to yield a near‐zero high‐cloud amount feedback, providing observational evidence against an iris feedback. Next, we find that tropical high clouds have risen but have also warmed, leading to a positive, but small, high‐cloud altitude feedback dominated by the LW feedback. Finally, we find that high clouds have been thinning, leading to a near‐zero high‐cloud optical depth feedback from a cancellation between negative LW and positive SW feedbacks. Overall, high clouds lead the total tropical cloud feedback to be small due to the negative LW‐positive SW feedback cancellations.
A Survey on Gravity Waves in the Brazilian Sector Based on Radiosonde Measurements From 32 Aerodromes
Authors: Brhian Alysson , Ridenti Marco A. , Roberto Marisa , de Abreu Alessandro J. , Abalde Guede José R. , de Campos Elson
Published: March 2024

In this paper, we applied a variety of statistical methods to study gravity waves in the troposphere and lower stratosphere in the Brazilian sector, using a large database from Instituto de Controle do Espaço Aéreo (ICEA) of radiosonde measurements carried out in 2014 at 32 locations in the Brazilian territory totaling 49,652 wind and temperature profiles. The average wind profiles were computed and classified by means of a hierarchical cluster analysis. The kinetic and potential energy densities of gravity waves were determined using a detrending technique based on the Least Squares Method and the Fast Fourier Transform. By analyzing the energy density time series it was found that tropospheric average values are consistently larger in the months of winter, late autumn and early spring. Stratospheric average values of variability and kinetic energy density are also consistently larger in this period. A systematic search for quasi monochromatic waves was carried out and their main characteristics such as horizontal/vertical wavelengths and velocities were determined both in the troposphere and lower stratosphere. A correlation analysis between the troposphere and the lower stratosphere based on the measured parameters was used to investigate the wave coupling between the two layers, and no significant correlation was found. Finally, a spatial correlation analysis between energy densities measured at different aerodromes in the same atmospheric layer was carried out, showing that energy densities are spatially correlated for distances less than 3,000–4,000 km.
Probing Into Ozone Production Through Photochemistry of Organic Peroxyl Radicals: Implications for Source Control
Authors: Liang Weiqing , Yu Haofei , Xu Han , Wang Zhenyu , Li Tiantian , Feng Yinchang , Russell Armistead , Shi Guoliang
Published: March 2024

Ozone (O3) pollution is a focus of the international community due to its health and environmental impacts. Organic peroxyl (RO2) radicals play a significant role in O3 initiation processes, which has implications for O3 mitigation. RO2 generated from volatile organic compounds (VOCs) sources contribute substantially to O3 formation. However, quantifying the RO2 from diverse sources is a great challenge. For the first time, we proposed a new hybrid Receptor‐Kinetic model to quantify sources contributions to RO2 from the perspective of molecular level and functional groups of VOCs. We revealed that 3‐Hydroxy‐2‐butylperoxy (BUT2OLO2), 4‐Hydroxy‐3‐methyl‐1‐butene‐3‐ylperoxy (ISOPBO2) and 1‐Hydroxypropane‐2‐ylperoxy (HYPROPO2) radicals were the dominant RO2, which were driven by reactions of cis/trans‐2‐butene (from Biogenic Emissions and Solvent Usage), isoprene (from Biogenic Emissions), and propylene (from Liquid Petroleum Gas Evaporation), respectively. The three dominant RO2 radicals contributed significantly to O3 production (28%, 10% and 14%), comparing with other 16 RO2. Sensitivity studies indicated that O3 production can be decreased effectively by reducing the dominant RO2 species for each source. Quantitative evidence suggested that targeting dominant RO2 sources can be a novel direction for O3 control.
A complex interplay of intra- and extracellular factors regulates the outcome of fetal- and adult-derived MLL-rearranged leukemia
Authors: Jassinskaja Maria , Ghosh Sudip , Watral Joanna , Davoudi Mina , Claesson Stern Melina , Daher Ugarit , Eldeeb Mohamed , Zhang Qinyu , Bryder David , Hansson Jenny
Published: March 2024

Infant and adult MLL1/KMT2A-rearranged (MLLr) leukemia represents a disease with a dismal prognosis. Here, we present a functional and proteomic characterization of in utero-initiated and adult-onset MLLr leukemia. We reveal that fetal MLL::ENL-expressing lymphomyeloid multipotent progenitors (LMPPs) are intrinsically programmed towards a lymphoid fate but give rise to myeloid leukemia in vivo, highlighting a complex interplay of intra- and extracellular factors in determining disease subtype. We characterize early proteomic events of MLL::ENL-mediated transformation in fetal and adult blood progenitors and reveal that whereas adult pre-leukemic cells are mainly characterized by retained myeloid features and downregulation of ribosomal and metabolic proteins, expression of MLL::ENL in fetal LMPPs leads to enrichment of translation-associated and histone deacetylases signaling proteins, and decreased expression of inflammation and myeloid differentiation proteins. Integrating the proteome of pre-leukemic cells with their secretome and the proteomic composition of the extracellular environment of normal progenitors highlights differential regulation of Igf2 bioavailability, as well as of VLA-4 dimer and its ligandome, upon initiation of fetal- and adult-origin leukemia, with implications for human MLLr leukemia cells’ ability to communicate with their environment through granule proteins. Our study has uncovered opportunities for targeting ontogeny-specific proteomic vulnerabilities in in utero-initiated and adult-onset MLLr leukemia.
Has telemedicine come to fruition? Parents’ and pediatricians’ perceptions and preferences regarding telemedicine
Authors: Bajwa Nadia M. , Perron Noelle Junod , Braillard Olivia , Achab Sophia , Hudelson Patricia , Dao Melissa Dominicé , Lüchinger Robin , Mazouri-Karker Sanae
Published: March 2024

Background

Telemedicine has increasingly become a viable option for patient care and may increase access to care. The aim of our study was to evaluate both parent and pediatrician perceptions, preferences, and acceptability regarding the use of different telemedicine modalities.

Methods

We conducted a cross-sectional survey of both parents and pediatricians in Geneva, Switzerland in 2021. The questionnaire focused on digital literacy, preferences, acceptability, advantages, and disadvantages regarding telemedicine (phone, email, video, and instant message). Descriptive statistics and comparisons of preferences and perceptions (Pearson Chi2 and logistic regression) were performed.

Results

Two hundred and twenty-two parents and 45 pediatricians participated. After face-to-face consultations, parents and pediatricians preferred the phone for simple medical advice, discussion of parameters, acute or chronic problems, and psychological support. Email was preferred for communication of results and prescription renewal. Main reasons for using telemedicine were avoiding travel and saving time. Disadvantages were lack of physical examination, technical problems, and unsuitability of the reason for consultation.

Conclusions

Understanding the factors that influence acceptance and satisfaction with telemedicine is vital for its successful implementation. Convenience, quality of care, trust, strong pediatrician–parent relationships, technical reliability, user-friendliness, and privacy considerations play significant roles in shaping parent and pediatrician attitudes toward telemedicine.

Impact

The COVID-19 pandemic spurred the expansion of the use of telemedicine in pediatric care. Few studies have addressed parent and pediatrician perceptions and preferences regarding telemedicine.

Both parents and pediatricians consider certain telemedicine modalities (phone, email, video, and instant message) pertinent in only specific clinical situations.

Advantages of telemedicine outweigh disadvantages with parents and pediatricians appreciating the increased access to care, time savings, and avoiding transport. However, the lack of a physical examination remains a significant disadvantage.

Convenience, quality of care, trust, strong pediatrician–parent relationship, technical reliability, user-friendliness, and privacy considerations play significant roles in shaping attitudes towards telemedicine.
PQR309, a dual PI3K/mTOR inhibitor, synergizes with gemcitabine by impairing the GSK-3β and STAT3/HSP60 signaling pathways to treat nasopharyngeal carcinoma
Authors: Cao Jiaxin , Zeng Kangmei , Chen Qun , Yang Ting , Lu Feiteng , Lin Chaozhuo , Zhan Jianhua , Ma Wenjuan , Zhou Ting , Huang Yan , Luo Fan , Zhao Hongyun
Published: March 2024

End-stage nasopharyngeal carcinoma (NPC) has unsatisfactory survival. The limited benefit of chemotherapy and the scarcity of targeted drugs are major challenges in NPC. New approaches to treat late-stage NPC are urgently required. In this study, we explored whether the dual PI3K/mTOR inhibitor, PQR309, exerted a favorable antineoplastic effect and sensitized the response to gemcitabine in NPC. We observed that PI3K expression was positive and elevated in 14 NPC cell lines compared with that in normal nasopharygeal cell lines. Patients with NPC with higher PI3K levels displayed poorer prognosis. We subsequently showed that PQR309 alone effectively decreased the viability, invasiveness, and migratory capability of NPC cells and neoplasm development in mice xenograft models, and dose-dependently induced apoptosis. More importantly, PQR309 remarkably strengthened the anti-NPC function of gemcitabine both in vivo and in vitro. Mechanistically, PQR309 sensitized NPC to gemcitabine by increasing caspase pathway-dependent apoptosis, blocking GSK-3β and STAT3/HSP60 signaling, and ablating epithelial-mesenchyme transition. Thus, targeting PI3K/mTOR using PQR309 might represent a treatment option to promote the response to gemcitabine in NPC, and provides a theoretical foundation for the study of targeted drugs combined with chemotherapy for NPC.
Alignment of brain embeddings and artificial contextual embeddings in natural language points to common geometric patterns
Authors: Goldstein Ariel , Grinstein-Dabush Avigail , Schain Mariano , Wang Haocheng , Hong Zhuoqiao , Aubrey Bobbi , Nastase Samuel A. , Zada Zaid , Ham Eric , Feder Amir , Gazula Harshvardhan , Buchnik Eliav , Doyle Werner , Devore Sasha , Dugan Patricia , Reichart Roi , Friedman Daniel , Brenner Michael , Hassidim Avinatan , Devinsky Orrin , Flinker Adeen , Hasson Uri
Published: March 2024

Contextual embeddings, derived from deep language models (DLMs), provide a continuous vectorial representation of language. This embedding space differs fundamentally from the symbolic representations posited by traditional psycholinguistics. We hypothesize that language areas in the human brain, similar to DLMs, rely on a continuous embedding space to represent language. To test this hypothesis, we densely record the neural activity patterns in the inferior frontal gyrus (IFG) of three participants using dense intracranial arrays while they listened to a 30-minute podcast. From these fine-grained spatiotemporal neural recordings, we derive a continuous vectorial representation for each word (i.e., a brain embedding) in each patient. Using stringent zero-shot mapping we demonstrate that brain embeddings in the IFG and the DLM contextual embedding space have common geometric patterns. The common geometric patterns allow us to predict the brain embedding in IFG of a given left-out word based solely on its geometrical relationship to other non-overlapping words in the podcast. Furthermore, we show that contextual embeddings capture the geometry of IFG embeddings better than static word embeddings. The continuous brain embedding space exposes a vector-based neural code for natural language processing in the human brain.
Recent autumn sea ice loss in the eastern Arctic enhanced by summer Asian-Pacific Oscillation
Authors: Zhou Botao , Song Ziyi , Yin Zhicong , Xu Xinping , Sun Bo , Hsu Pangchi , Chen Haishan
Published: March 2024

Recent rapid Arctic sea ice loss was documented as combined results from anthropogenic forcing and climate system internal variability. However, the role of internal variability is not well understood. Here, we propose that the Asian-Pacific Oscillation (APO), an intrinsic atmospheric mode featuring out-of-phase variations in upper-tropospheric temperatures between Asia and the North Pacific, is one driver for autumn sea ice variability in the eastern Arctic. The positive summer APO favors warming of the mid-latitude North Atlantic sea surface temperatures. This warming persists to autumn and in turn triggers strong anticyclonic anomalies over the Barents-Kara-Laptev Seas and weak lower-tropospheric cyclonic anomalies over the East Siberian Sea, enhancing moisture transport into the eastern Arctic. Such changes consequently increase lower-tropospheric humidity, downwelling longwave radiation, and surface air temperature in the eastern Arctic, thereby melting sea ice. Hence, a recent tendency of the summer APO towards the positive phase accelerates autumn sea ice loss in the eastern Arctic.
Supramolecular polynuclear clusters sustained cubic hydrogen bonded frameworks with octahedral cages for reversible photochromism
Authors: Ding Xiaojun , Chen Jing , Ye Gang
Published: March 2024

Developing supramolecular porous crystalline frameworks with tailor-made architectures from advanced secondary building units (SBUs) remains a pivotal challenge in reticular chemistry. Particularly for hydrogen-bonded organic frameworks (HOFs), construction of geometrical cavities through secondary units has been rarely achieved. Herein, a body-centered cubic HOF (TCA_NH4) with octahedral cages was constructed by a C3-symmetric building block and NH4+ node-assembled cluster (NH4)4(COOH)8(H2O)2 that served as supramolecular secondary building units (SSBUs), akin to the polynuclear SBUs in reticular chemistry. Specifically, the octahedral cages could encapsulate four homogenous haloforms including CHCl3, CHBr3, and CHI3 with truncated octahedron configuration. Crystallographic evidence revealed the cages served as spatially-confined nanoreactors, enabling fast, broadband photochromic effect associated with the reversible photo/thermal transformation between encapsulated CHI3 and I2. Overall, this work provides a strategy by shaping SSBUs to expand the framework topology of HOFs and a prototype of hydrogen-bonded nanoreactors to accommodate reversible photochromic reactions.
Stereoselective assembly of C-oligosaccharides via modular difunctionalization of glycals
Authors: Ding Ya-Nan , Xu Mei-Ze , Huang Yan-Chong , Ackermann Lutz , Kong Xiangtao , Liu Xue-Yuan , Liang Yong-Min
Published: March 2024

C-oligosaccharides are found in natural products and drug molecules. Despite the considerable progress made during the last decades, modular and stereoselective synthesis of C-oligosaccharides continues to be challenging and underdeveloped compared to the synthesis technology of O-oligosaccharides. Herein, we design a distinct strategy for the stereoselective and efficient synthesis of C-oligosaccharides via palladium-catalyzed nondirected C1–H glycosylation/C2-alkenylation, cyanation, and alkynylation of 2-iodoglycals with glycosyl chloride donors while realizing the difunctionalization of 2-iodoglycals. The catalysis approach tolerates various functional groups, including derivatives of marketed drugs and natural products. Notably, the obtained C-oligosaccharides can be further transformed into various C-glycosides while fully conserving the stereochemistry. The results of density functional theory (DFT) calculations support oxidative addition mechanism of alkenyl-norbornyl-palladacycle (ANP) intermediate with α-mannofuranose chloride and the high stereoselectivity of glycosylation is due to steric hindrance.
Tailoring coordination environments of single-atom electrocatalysts for hydrogen evolution by topological heteroatom transfer
Authors: Qian Sheng , Xu Feng , Fan Yu , Cheng Ningyan , Xue Huaiguo , Yuan Ye , Gautier Romain , Jiang Tengfei , Tian Jingqi
Published: March 2024

The rational design of carbon-supported transition-metal single-atom catalysts requires the precise arrangement of heteroatoms within the single-atom catalysts. However, achieving this design is challenging due to the collapse of the structure during the pyrolysis. Here, we introduce a topological heteroatom-transfer strategy to prevent the collapse and accurately control the P coordination in carbon-supported single-atom catalysts. As an illustration, we have prepared self-assembled helical fibers with encapsulated cavities. Within these cavities, adjustable functional groups can chelate metal ions (Nx···Mn+···Oy), facilitating the preservation of the structure during the pyrolysis based phosphidation. This process allows for the transfer of heteroatoms from the assembly into single-atom catalysts, resulting in the precise coordination tailoring. Notably, the Co–P2N2–C catalyst exhibits electrocatalytic performance as a non-noble metal single-atom catalyst for alkaline hydrogen evolution, attaining a current density of 100 mA cm−2 with an overpotential of only 131 mV.
Dynamical evolution of CO2 and H2O on garnet electrolyte elucidated by ambient pressure X-ray spectroscopies
Authors: Zhang Nian , Ren Guoxi , Li Lili , Wang Zhi , Yu Pengfei , Li Xiaobao , Zhou Jing , Zhang Hui , Zhang Linjuan , Liu Zhi , Liu Xiaosong
Published: March 2024

Garnet-type Li6.5La3Zr1.5Ta0.5O12 (LLZO) is considered a promising solid electrolyte, but the surface degradation in air hinders its application for all-solid-state battery. Recent studies have mainly focused on the final products of the LLZO surface reactions due to lacking of powerful in situ characterization methods. Here, we use ambient pressure X-ray spectroscopies to in situ investigate the dynamical evolution of LLZO surface in different gas environments. The newly developed ambient pressure mapping of resonant Auger spectroscopy clearly distinguishes the lithium containing species, including LiOH, Li2O, Li2CO3 and lattice oxygen. The reaction of CO2 with LLZO to form Li2CO3 is found to be a thermodynamically favored self-limiting reaction. On the contrary, the reaction of H2O with LLZO lags behind that of CO2, but intensifies at high pressure. More interestingly, the results provide direct spectroscopic evidence for the existence of Li+/H+ exchange and reveal the importance of the initial layer formed on clean electrolyte surface in determining their air stability. This work demonstrates that the newly developed in situ technologies pave a new way to investigate the oxygen evolution and surface degradation mechanism in energy materials.
Quantitative, high-sensitivity measurement of liquid analytes using a smartphone compass
Authors: Ferris Mark , Zabow Gary
Published: March 2024

Smartphone ubiquity has led to rapid developments in portable diagnostics. While successful, such platforms are predominantly optics-based, using the smartphone camera as the sensing interface. By contrast, magnetics-based modalities exploiting the smartphone compass (magnetometer) remain unexplored, despite inherent advantages in optically opaque, scattering or auto-fluorescing samples. Here we report smartphone analyte sensing utilizing the built-in magnetometer for signal transduction via analyte-responsive magnetic-hydrogel composites. As these hydrogels dilate in response to targeted stimuli, they displace attached magnetic material relative to the phone’s magnetometer. Using a bilayer hydrogel geometry to amplify this motion allows for sensitive, optics-free, quantitative liquid-based analyte measurements that require neither any electronics nor power beyond that contained within the smartphone itself. We demonstrate this concept with glucose-specific and pH-responsive hydrogels, including glucose detection down to single-digit micromolar concentrations with potential for extension to nanomolar sensitivities. The platform is adaptable to numerous measurands, opening a path towards portable, inexpensive sensing of multiple analytes or biomarkers of interest.
Flexible large-area ultrasound arrays for medical applications made using embossed polymer structures
Authors: van Neer Paul L. M. J. , Peters Laurens C. J. M. , Verbeek Roy G. F. A. , Peeters Bart , de Haas Gerard , Hörchens Lars , Fillinger Laurent , Schrama Thijs , Merks-Swolfs Egon J. W. , Gijsbertse Kaj , Saris Anne E. C. M. , Mozaffarzadeh Moein , Menssen Jan M. , de Korte Chris L. , van der Steen Jan-Laurens P. J. , Volker Arno W. F. , Gelinck Gerwin H.
Published: March 2024

With the huge progress in micro-electronics and artificial intelligence, the ultrasound probe has become the bottleneck in further adoption of ultrasound beyond the clinical setting (e.g. home and monitoring applications). Today, ultrasound transducers have a small aperture, are bulky, contain lead and are expensive to fabricate. Furthermore, they are rigid, which limits their integration into flexible skin patches. New ways to fabricate flexible ultrasound patches have therefore attracted much attention recently. First prototypes typically use the same lead-containing piezo-electric materials, and are made using micro-assembly of rigid active components on plastic or rubber-like substrates. We present an ultrasound transducer-on-foil technology based on thermal embossing of a piezoelectric polymer. High-quality two-dimensional ultrasound images of a tissue mimicking phantom are obtained. Mechanical flexibility and effective area scalability of the transducer are demonstrated by functional integration into an endoscope probe with a small radius of 3 mm and a large area (91.2×14 mm2) non-invasive blood pressure sensor.
TM4SF19-mediated control of lysosomal activity in macrophages contributes to obesity-induced inflammation and metabolic dysfunction
Authors: Choi Cheoljun , Jeong Yujin L. , Park Koung-Min , Kim Minji , Kim Sangseob , Jo Honghyun , Lee Sumin , Kim Heeseong , Choi Garam , Choi Yoon Ha , Seong Je Kyung , Namgoong Sik , Chung Yeonseok , Jung Young-Suk , Granneman James G. , Hyun Young-Min , Kim Jong Kyoung , Lee Yun-Hee
Published: March 2024

Adipose tissue (AT) adapts to overnutrition in a complex process, wherein specialized immune cells remove and replace dysfunctional and stressed adipocytes with new fat cells. Among immune cells recruited to AT, lipid-associated macrophages (LAMs) have emerged as key players in obesity and in diseases involving lipid stress and inflammation. Here, we show that LAMs selectively express transmembrane 4 L six family member 19 (TM4SF19), a lysosomal protein that represses acidification through its interaction with Vacuolar-ATPase. Inactivation of TM4SF19 elevates lysosomal acidification and accelerates the clearance of dying/dead adipocytes in vitro and in vivo. TM4SF19 deletion reduces the LAM accumulation and increases the proportion of restorative macrophages in AT of male mice fed a high-fat diet. Importantly, male mice lacking TM4SF19 adapt to high-fat feeding through adipocyte hyperplasia, rather than hypertrophy. This adaptation significantly improves local and systemic insulin sensitivity, and energy expenditure, offering a potential avenue to combat obesity-related metabolic dysfunction.
Transcription-driven DNA supercoiling counteracts H-NS-mediated gene silencing in bacterial chromatin
Authors: Figueroa-Bossi Nara , Fernández-Fernández Rocío , Kerboriou Patricia , Bouloc Philippe , Casadesús Josep , Sánchez-Romero María Antonia , Bossi Lionello
Published: March 2024

In all living cells, genomic DNA is compacted through interactions with dedicated proteins and/or the formation of plectonemic coils. In bacteria, DNA compaction is achieved dynamically, coordinated with dense and constantly changing transcriptional activity. H-NS, a major bacterial nucleoid structuring protein, is of special interest due to its interplay with RNA polymerase. H-NS:DNA nucleoprotein filaments inhibit transcription initiation by RNA polymerase. However, the discovery that genes silenced by H-NS can be activated by transcription originating from neighboring regions has suggested that elongating RNA polymerases can disassemble H-NS:DNA filaments. In this study, we present evidence that transcription-induced counter-silencing does not require transcription to reach the silenced gene; rather, it exerts its effect at a distance. Counter-silencing is suppressed by introducing a DNA gyrase binding site within the intervening segment, suggesting that the long-range effect results from transcription-driven positive DNA supercoils diffusing toward the silenced gene. We propose a model wherein H-NS:DNA complexes form in vivo on negatively supercoiled DNA, with H-NS bridging the two arms of the plectoneme. Rotational diffusion of positive supercoils generated by neighboring transcription will cause the H-NS-bound negatively-supercoiled plectoneme to “unroll” disrupting the H-NS bridges and releasing H-NS.
Ultrathin organosiloxane membrane for precision organic solvent nanofiltration
Authors: Choi Jihoon , Choi Keonwoo , Kwon YongSung , Kim Daehun , Yoo Youngmin , Im Sung Gap , Koh Dong-Yeun
Published: March 2024

Promising advances in membrane technology can lead to energy-saving and eco-friendly solutions in industrial sectors. This work demonstrates a highly selective membrane with ultrathin and highly interconnected organosiloxane polymer nanolayers by initiated chemical vapor deposition to effectively separate solutes within the molecular weight range of 150–300 g mol−1. We optimize the poly(1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane) membrane by adjusting both the thickness of the selective layer and the pore sizes of its support membranes. Notably, the 29 nm selective layer imparts a uniformly narrow molecular sieving property, providing a record-high solute-solute selectivity of 39.88 for different-sized solutes. Furthermore, a solute-solute selectivity of 11.04 was demonstrated using the real-world active pharmaceutical ingredient mixture of Acyclovir and Valacyclovir, key components for Herpes virus treatment, despite their molecular weight difference of less than 100 g mol−1. The highly interconnected membrane is expected to meet rigorous requirements for high-standard active pharmaceutical ingredient separation.
Structural bases of inhibitory mechanism of CaV1.2 channel inhibitors
Authors: Wei Yiqing , Yu Zhuoya , Wang Lili , Li Xiaojing , Li Na , Bai Qinru , Wang Yuhang , Li Renjie , Meng Yufei , Xu Hao , Wang Xianping , Dong Yanli , Huang Zhuo , Zhang Xuejun Cai , Zhao Yan
Published: March 2024

The voltage-gated calcium channel CaV1.2 is essential for cardiac and vessel smooth muscle contractility and brain function. Accumulating evidence demonstrates that malfunctions of CaV1.2 are involved in brain and heart diseases. Pharmacological inhibition of CaV1.2 is therefore of therapeutic value. Here, we report cryo-EM structures of CaV1.2 in the absence or presence of the antirheumatic drug tetrandrine or antihypertensive drug benidipine. Tetrandrine acts as a pore blocker in a pocket composed of S6II, S6III, and S6IV helices and forms extensive hydrophobic interactions with CaV1.2. Our structure elucidates that benidipine is located in the DIII-DIV fenestration site. Its hydrophobic sidechain, phenylpiperidine, is positioned at the exterior of the pore domain and cradled within a hydrophobic pocket formed by S5DIII, S6DIII, and S6DIV helices, providing additional interactions to exert inhibitory effects on both L-type and T-type voltage gated calcium channels. These findings provide the structural foundation for the rational design and optimization of therapeutic inhibitors of voltage-gated calcium channels.
Three-stage ultrafast demagnetization dynamics in a monolayer ferromagnet
Authors: Wu Na , Zhang Shengjie , Chen Daqiang , Wang Yaxian , Meng Sheng
Published: March 2024

Intense laser pulses can be used to demagnetize a magnetic material on an extremely short timescale. While this ultrafast demagnetization offers the potential for new magneto-optical devices, it poses challenges in capturing coupled spin-electron and spin-lattice dynamics. In this article, we study the photoinduced ultrafast demagnetization of a prototype monolayer ferromagnet Fe3GeTe2 and resolve the three-stage demagnetization process characterized by an ultrafast and substantial demagnetization on a timescale of 100 fs, followed by light-induced coherent A1g phonon dynamics which is strongly coupled to the spin dynamics in the next 200–800 fs. In the third stage, chiral lattice vibrations driven by nonlinear phonon couplings, both in-plane and out-of-plane are produced, resulting in significant spin precession. Nonadiabatic effects are found to introduce considerable phonon hardening and suppress the spin-lattice couplings during demagnetization. Our results advance our understanding of dynamic charge-spin-lattice couplings in the ultrafast demagnetization and evidence angular momentum transfer between the phonon and spin degrees of freedom.
Clinically used broad-spectrum antibiotics compromise inflammatory monocyte-dependent antibacterial defense in the lung
Authors: Dörner Patrick J. , Anandakumar Harithaa , Röwekamp Ivo , Fiocca Vernengo Facundo , Millet Pascual-Leone Belén , Krzanowski Marta , Sellmaier Josua , Brüning Ulrike , Fritsche-Guenther Raphaela , Pfannkuch Lennart , Kurth Florian , Milek Miha , Igbokwe Vanessa , Löber Ulrike , Gutbier Birgitt , Holstein Markus , Heinz Gitta Anne , Mashreghi Mir-Farzin , Schulte Leon N. , Klatt Ann-Brit , Caesar Sandra , Wienhold Sandra-Maria , Offermanns Stefan , Mack Matthias , Witzenrath Martin , Jordan Stefan , Beule Dieter , Kirwan Jennifer A. , Forslund Sofia K. , Wilck Nicola , Bartolomaeus Hendrik , Heimesaat Markus M. , Opitz Bastian
Published: March 2024

Hospital-acquired pneumonia (HAP) is associated with high mortality and costs, and frequently caused by multidrug-resistant (MDR) bacteria. Although prior antimicrobial therapy is a major risk factor for HAP, the underlying mechanism remains incompletely understood. Here, we demonstrate that antibiotic therapy in hospitalized patients is associated with decreased diversity of the gut microbiome and depletion of short-chain fatty acid (SCFA) producers. Infection experiments with mice transplanted with patient fecal material reveal that these antibiotic-induced microbiota perturbations impair pulmonary defense against MDR Klebsiella pneumoniae. This is dependent on inflammatory monocytes (IMs), whose fatty acid receptor (FFAR)2/3-controlled and phagolysosome-dependent antibacterial activity is compromized in mice transplanted with antibiotic-associated patient microbiota. Collectively, we characterize how clinically relevant antibiotics affect antimicrobial defense in the context of human microbiota, and reveal a critical impairment of IM´s antimicrobial activity. Our study provides additional arguments for the rational use of antibiotics and offers mechanistic insights for the development of novel prophylactic strategies to protect high-risk patients from HAP.
Photo-modulated activation of organic bases enabling microencapsulation and on-demand reactivity
Authors: Li Wenle , Lu Xiaocun , Diamond Jacob M. , Shen Chengtian , Jiang Bo , Sun Shi , Moore Jeffrey S. , Sottos Nancy R.
Published: March 2024

A method is developed for facile encapsulation of reactive organic bases with potential application for autonomous damage detection and self-healing polymers. Highly reactive chemicals such as bases and acids are challenging to encapsulate by traditional oil-water emulsion techniques due to unfavorable physical and chemical interactions. In this work, reactivity of the bases is temporarily masked with photo-removable protecting groups, and the resulting inactive payloads are encapsulated via an in situ emulsion-templated interfacial polymerization method. The encapsulated payloads are then activated to restore the organic bases via photo irradiation, either before or after being released from the core-shell carriers. The efficacy of the photo-activated capsules is demonstrated by a damage-triggered, pH-induced color change in polymeric coatings and by recovery of adhesive strength of a damaged interface. Given the wide range of potential photo-deprotection chemistries, this encapsulation scheme provides a simple but powerful method for storage and targeted delivery of a broad variety of reactive chemicals, promoting design of diverse autonomous functionalities in polymeric materials.