bluuebunny/crossref_metadata_2025 huggingface dataset:
Space Weather Disturbances in Non‐Stormy Times: Occurrence of dB/dt Spikes During Three Solar Cycles
Authors: Hamrin M. , Schillings A. , Opgenoorth H. , Nesbit‐Östman S. , Krämer E. , Araújo J. , Baddeley L. , Gunell H. , Pitkänen T. , Gjerloev J. , Barnes R. J.
Published: October 2023

Spatio‐temporal variations of ionospheric currents cause rapid magnetic field variations at ground level and Geomagnetically Induced Currents (GICs) that can be harmful for human infrastructure. The risk for large excursions in the magnetic field time derivative, “dB/dt spikes”, is known to be high during geomagnetic storms and substorms. However, less is known about the occurrence of spikes during non‐stormy times. We use data from ground‐based globally covering magnetometers (SuperMAG database) from the years 1985–2021. We investigate the spike occurrence (|dB/dt| > 100 nT/min) as a function of magnetic local time (MLT), magnetic latitude (Mlat), and the solar cycle phases during non‐stormy times (−15 nT ≤ SYM‐H < 0). We sort our data into substorm (AL < 200 nT) intervals (“SUB”) and less active intervals between consecutive substorms (“nonSUB”). We find that spikes commonly occur in both SUBs and nonSUBs during non‐stormy times (3–23 spikes/day), covering 18–12 MLT and 65°–80° Mlat. This also implies a risk for infrastructure damage during non‐stormy times, especially when several spikes occur nearby in space and time, possibly causing infrastructure weathering. We find that spikes are more common in the declining phase of the solar cycle, and that the occurrence of SUB spikes propagates from one midnight to one morning hotspot with ∼10 min in MLT for each minute in universal time (UTC). Finally, we discuss causes for the spikes in terms of spatio‐temporal variations of ionospheric currents.
Simulating Electron Distribution Function in the Pulsating Aurora Using Particle and Wave Data of ARASE Satellite
Authors: Khazanov George V. , Ma Qianli , Chu Mike
Published: October 2023

Decades lasting research on the pulsating aurora suggested that this phenomenon forms as result of interactions between the magnetospheric keVs electrons and whistler‐mode chorus waves. Arase satellite observation reported the direct evidence for this process confirming in situ measurement of highly correlated precipitated electrons and chorus wave activity. This paper presents the theoretical analysis of this observational event based on the SuperThermal Electron Transport (STET) code that simulates the highly dynamic environment of measured waves and particle data. Specifically, the STET code simulated results confirms the delicate loss‐cone observation results of this mission and further reveals the broader energy range of precipitated electron fluxes that was not measurable by Arase satellite.
Ambient‐Noise Wave‐Equation Tomography of the Alps and Ligurian‐Provence Basin
Authors: Nouibat A. , Brossier R. , Stehly L. , Cao J. , Paul A. ,   Cifalps Team and AlpArray Working Group
Published: October 2023

Taking benefit of the AlpArray temporary network and permanent networks in W‐Europe, we construct a 3‐D onshore‐offshore velocity model of the crust and upper mantle using ambient‐noise wave‐equation tomography. We use a frequency‐dependent phase traveltime misfit function in an iterative procedure to refine a recent 3‐D Vs model computed from a Bayesian two‐step ambient noise tomography. Observed waveforms consist of vertical‐component noise correlations from 600 broadband stations in the Alps and surroundings, including ocean‐bottom seismometers in the Ligurian sea. We perform 3‐D inversion in the 5–85 s period range. In the long‐period band (20–85 s), an elastic approximation is considered, while in the 5–20 s band, we account for the effect of water layer in the Ligurian sea by applying a fluid‐solid coupling for acoustic‐elastic waveform simulations. The resulting Vs model enhances the shape and contrast of velocity structures, accounting for 3‐D and finite‐frequency effects. It emphasizes the deep sediments of the Ligurian‐Provence basin and focuses on the low‐velocity anomalies of the crust in the W‐Alps. We obtain a high‐resolution Moho depth map covering the Alps and Ligurian sea. In the W‐Alps, this map confirms the deepening of the European crust following the subduction beneath Adria and the existence of major structures such as the Moho jump beneath the external crystalline massifs and shallow depths associated with the Ivrea Body. It provides further constraints on the deep structure beneath the Ligurian‐Provence basin, regarding the lateral and along‐strike crustal‐thickness variations from the oceanic domain to the conjugate margins.
Microphysical Characteristics of Snowfall on the Southeastern Tibetan Plateau
Authors: Xu Xin , Chen Xuelong , Zhao Xi , Cao Dianbin , Liu Yajing , Li Luhan , Ma Yaoming
Published: October 2023

Snowfall on the Tibetan Plateau (TP) is crucially important to the hydrological cycle and glacier acceleration over the TP and surroundings. Climate and weather models are challenged by biases and uncertainties in representing microphysical characteristics of snowfall over TP. In order to bridge the gaps in our understanding of microphysical characteristics of snowfall on the southeastern TP (SETP), an integrated and systematic measurement is conducted at the South‐East Tibetan Plateau Station during the two winters of 2022–2023. It is the first time to conduct a long‐term measurement of microphysical characteristics of snowfall on the SETP. The major objective of this campaign was to collect cloud microphysical properties including, fall velocity, aspect ratio, and particle size distribution (PSD). The results show that the particle number concentration is less than 103 mm−1·m−3, which is one to two orders of magnitude smaller than that reported in low‐altitudes in eastern China. The shape parameter μ is mainly in the range 0–4, and the slope parameter λ is mainly in the range 3–7 mm−1, exceeding the values for eastern China. In heavy snowfall processes (snowfall rate (SR) exceeding 2 mm/hr), the collision‐coalescence process between snowfall particles is enhanced, and the number concentration of small particles decreases with SR, whereas that of large particles increases. A negative correlation was observed between the aspect ratio and the diameter of snowfall particles. The microphysical characteristics of snowfall will be used to improve the microphysical scheme and evaluate the representation of precipitation in the climate model.
Paleogene Paleohydrology of Ellesmere and Axel Heiberg Islands (Arctic Canada) From Palustrine Carbonates
Authors: Padgett Ashly B. , Hyland Ethan G. , West Christopher K. , Burgener Landon K. , Greenwood David R. , Basinger James F.
Published: October 2023

Ancient greenhouse periods are useful analogs for predicting effects of anthropogenic climate change on regional and global temperature and precipitation patterns. A paucity of terrestrial data from polar regions during warm episodes challenges our understanding of polar climate responses to natural/anthropogenic change and therefore our ability to predict future changes in precipitation. Ellesmere and Axel Heiberg Islands in the Canadian Arctic preserve terrestrial deposits spanning the late Paleocene to middle Eocene (59–45 Ma). Here we expand on existing regional sedimentology and paleontology through the addition of stable (δ13C, δ18O) and clumped (Δ47) isotope analyses on palustrine carbonates. δ13C isotope values range from −4.6 to +12.3‰ (VPDB), and δ18O isotope values range from −23.1 to −15.2‰ (VPDB). Both carbon and oxygen isotope averages decrease with increasing diagenetic alteration. Unusually enriched carbon isotope (δ13C) values suggest that analyzed carbonates experienced repeated dissolution‐precipitation enrichment cycles, potentially caused by seasonal fluctuations in water availability resulting in summer carbonate dissolution followed by winter carbonate re‐precipitation. Stable isotopes suggest some degree of precipitation seasonality or reduction in winter water availability in the Canadian Arctic during the Paleogene. Clumped (Δ47) temperature estimates range from 52 to 121°C and indicate low temperature solid‐state reordering of micritic samples and diagenetic recrystallization in sparry samples. Average temperatures agree with vitrinite reflectance data for Eureka Sound Group and underlying sediments, highlighting structural complexity across the region. Broadly, combined stable and clumped isotope data from carbonates in complex systems are effective for describing both paleoclimatic and post‐burial conditions.
Characterizing the regulatory Fas (CD95) epitope critical for agonist antibody targeting and CAR-T bystander function in ovarian cancer
Authors: Mondal Tanmoy , Gaur Himanshu , Wamba Brice E. N. , Michalak Abby Grace , Stout Camryn , Watson Matthew R. , Aleixo Sophia L. , Singh Arjun , Condello Salvatore , Faller Roland , Leiserowitz Gary Scott , Bhatnagar Sanchita , Tushir-Singh Jogender
Published: October 2023

Receptor clustering is the most critical step to activate extrinsic apoptosis by death receptors belonging to the TNF superfamily. Although clinically unsuccessful, using agonist antibodies, the death receptors-5 remains extensively studied from a cancer therapeutics perspective. However, despite its regulatory role and elevated function in ovarian and other solid tumors, another tumor-enriched death receptor called Fas (CD95) remained undervalued in cancer immunotherapy until recently, when its role in off-target tumor killing by CAR-T therapies was imperative. By comprehensively analyzing structure studies in the context of the binding epitope of FasL and various preclinical Fas agonist antibodies, we characterize a highly significant patch of positively charged residue epitope (PPCR) in its cysteine-rich domain 2 of Fas. PPCR engagement is indispensable for superior Fas agonist signaling and CAR-T bystander function in ovarian tumor models. A single-point mutation in FasL or Fas that interferes with the PPCR engagement inhibited apoptotic signaling in tumor cells and T cells. Furthermore, considering that clinical and immunological features of the autoimmune lymphoproliferative syndrome (ALPS) are directly attributed to homozygous mutations in FasL, we reveal differential mechanistic details of FasL/Fas clustering at the PPCR interface compared to described ALPS mutations. As Fas-mediated bystander killing remains vital to the success of CAR-T therapies in tumors, our findings highlight the therapeutic analytical design for potentially effective Fas-targeting strategies using death agonism to improve cancer immunotherapy in ovarian and other solid tumors.
Extracellular vesicles from subjects with COPD modulate cancer initiating cells phenotype through HIF-1α shuttling
Authors: Petraroia Ilaria , Ghidotti Patrizia , Bertolini Giulia , Pontis Francesca , Roz Luca , Balsamo Melissa , Suatoni Paola , Pastorino Ugo , Ferretti Anna Maria , Sozzi Gabriella , Fortunato Orazio
Published: October 2023

Chronic obstructive pulmonary disease (COPD) is a risk factor for lung cancer development. COPD induces activation of hypoxia-induced signaling, causing remodeling of surrounding microenvironmental cells also modulating the release and cargo of their extracellular vesicles (EVs). We aimed to evaluate the potential role of circulating EVs from COPD subjects in lung cancer onset. Plasma-EVs were isolated by ultracentrifugation from heavy smoker volunteers with (COPD-EVs) or without (heavy smoker-EVs, HS-EV) COPD and characterized following MISEV guidelines. Immortalized human bronchial epithelial cells (CDK4, hTERT-HBEC3-KT), genetically modified with different oncogenic alterations commonly found in lung cancer (sh-p53, KRASV12), were used to test plasma-EVs pro-tumorigenic activity in vitro. COPD-EVs mainly derived from immune and endothelial cells. COPD-EVs selectively increased the subset of CD133+CXCR4+ metastasis initiating cells (MICs) in HBEC-sh-p53-KRASV12high cells and stimulated 3D growth, migration/invasion, and acquisition of mesenchymal traits. These effects were not observed in HBEC cells bearing single oncogenic mutation (sh-p53 or KRASV12). Mechanistically, hypoxia-inducible factor 1-alpha (HIF-1α) transferred from COPD-EVs triggers CXCR4 pathway activation that in turn mediates MICs expansion and acquisition of pro-tumorigenic effects. Indeed, HIF-1α inhibition or CXCR4 silencing prevented the acquisition of malignant traits induced by COPD-EVs alone. Hypoxia recapitulates the effects observed with COPD-EVs in HBEC-sh-p53-KRASV12high cells. Notably, higher levels of HIF-1α were observed in EVs from COPD subjects who subsequently developed cancer compared to those who remained cancer-free. Our findings support a role of COPD-EVs to promote the expansion of MICs in premalignant epithelial cells through HIF-1α-CXCR4 axis activation thereby potentially sustaining lung cancer progression.
Growing recyclable and healable piezoelectric composites in 3D printed bioinspired structure for protective wearable sensor
Authors: He Qingqing , Zeng Yushun , Jiang Laiming , Wang Ziyu , Lu Gengxi , Kang Haochen , Li Pei , Bethers Brandon , Feng Shengwei , Sun Lizhi , Sun Peter , Gong Chen , Jin Jie , Hou Yue , Jiang Runjian , Xu Wenwu , Olevsky Eugene , Yang Yang
Published: October 2023

Bionic multifunctional structural materials that are lightweight, strong, and perceptible have shown great promise in sports, medicine, and aerospace applications. However, smart monitoring devices with integrated mechanical protection and piezoelectric induction are limited. Herein, we report a strategy to grow the recyclable and healable piezoelectric Rochelle salt crystals in 3D-printed cuttlebone-inspired structures to form a new composite for reinforcement smart monitoring devices. In addition to its remarkable mechanical and piezoelectric performance, the growth mechanisms, the recyclability, the sensitivity, and repairability of the 3D-printed Rochelle salt cuttlebone composite were studied. Furthermore, the versatility of composite has been explored and applied as smart sensor armor for football players and fall alarm knee pads, focusing on incorporated mechanical reinforcement and electrical self-sensing capabilities with data collection of the magnitude and distribution of impact forces, which offers new ideas for the design of next-generation smart monitoring electronics in sports, military, aerospace, and biomedical engineering.
Projected changes in atmospheric moisture transport contributions associated with climate warming in the North Atlantic
Authors: Fernández-Alvarez José C. , Pérez-Alarcón Albenis , Eiras-Barca Jorge , Rahimi Stefan , Nieto Raquel , Gimeno Luis
Published: October 2023

Global warming and associated changes in atmospheric circulation patterns are expected to alter the hydrological cycle, including the intensity and position of moisture sources. This study presents predicted changes for the middle and end of the 21st century under the SSP5-8.5 scenario for two important extratropical moisture sources: the North Atlantic Ocean (NATL) and Mediterranean Sea (MED). Changes over the Iberian Peninsula—considered as a strategic moisture sink for its location—are also studied in detail. By the end of the century, moisture from the NATL will increase precipitation over eastern North America in winter and autumn and on the British Isles in winter. Moisture from the MED will increase precipitation over the southern and western portions of the Mediterranean continental area. Precipitation associated with the MED moisture source will decrease mainly over eastern Europe, while that associated with the NATL will decrease over western Europe and Africa. Precipitation recycling on the Iberian Peninsula will increase in all seasons except summer for mid-century. Climate change, as simulated by CESM2 thus modifies atmospheric moisture transport, affecting regional hydrological cycles.
A randomized controlled trial testing a virtual program for Asian American women breast cancer survivors
Authors: Im Eun-Ok , Chee Wonshik , Paul Sudeshna , Choi Mi-Young , Kim Seo Yun , Deatrick Janet A. , Inouye Jillian , Ma Grace , Meghani Salimah , Nguyen Giang T. , Schapira Marilyn M. , Ulrich Connie M. , Yeo SeonAe , Bao Ting , Shin David , Mao Jun J.
Published: October 2023

A culturally tailored virtual program could meet the survivorship needs of Asian American women breast cancer survivors (AABC). This study aims to determine the efficacy of a culturally tailored virtual information and coaching/support program (TICAA) in improving AABC’s survivorship experience. A randomized clinical trial (NCT02803593) was conducted from January 2017 to June 2020 among 199 AABC. The intervention group utilized TICAA and the American Cancer Society [ACS] website while the control group used only ACS website for 12 weeks. The outcomes were measured using the SCNS-34SF (needs; primary), the MSAS-SF (symptoms; secondary), and the FACT-B (quality of life; secondary). The data were analyzed using an intent-to-treat approach. The intervention group showed significant reductions in their needs from the baseline (T0) to post 4 weeks (T1) and to post 12 weeks (T2). Although the changes were not statistically significant, the intervention group had decreased symptoms from T0 to T2 while the control group had an increase in their symptoms. The intervention group had a significant increase in their quality of life from T0 to T2. A culturally tailored virtual program could therefore improve quality of life in AABC patients. Trial Registration: To Enhance Breast Cancer Survivorship of Asian Americans (TICAA), NCT02803593, https://clinicaltrials.gov/ct2/show/NCT02803593?titles=TICAA&draw=2&rank=1
Structural basis for the unique molecular properties of broad-range phospholipase C from Listeria monocytogenes
Authors: Petrišič Nejc , Adamek Maksimiljan , Kežar Andreja , Hočevar Samo B. , Žagar Ema , Anderluh Gregor , Podobnik Marjetka
Published: October 2023

Listeriosis is one of the most serious foodborne diseases caused by the intracellular bacterium Listeria monocytogenes. Its two major virulence factors, broad-range phospholipase C (LmPC-PLC) and the pore-forming toxin listeriolysin O (LLO), enable the bacterium to spread in the host by destroying cell membranes. Here, we determine the crystal structure of LmPC-PLC and complement it with the functional analysis of this enzyme. This reveals that LmPC-PLC has evolved several structural features to regulate its activity, including the invariant position of the N-terminal tryptophan (W1), the structurally plastic active site, Zn2+-dependent activity, and the tendency to form oligomers with impaired enzymatic activity. We demonstrate that the enzymatic activity of LmPC-PLC can be specifically inhibited by its propeptide added in trans. Furthermore, we show that the phospholipase activity of LmPC-PLC facilitates the pore-forming activity of LLO and affects the morphology of LLO oligomerization on lipid membranes, revealing the multifaceted synergy of the two virulence factors.
Mitigating a TDP-43 proteinopathy by targeting ataxin-2 using RNA-targeting CRISPR effector proteins
Authors: Zeballos C. M. Alejandra , Moore Hayden J. , Smith Tyler J. , Powell Jackson E. , Ahsan Najah S. , Zhang Sijia , Gaj Thomas
Published: October 2023

The TDP-43 proteinopathies, which include amyotrophic lateral sclerosis and frontotemporal dementia, are a devastating group of neurodegenerative disorders that are characterized by the mislocalization and aggregation of TDP-43. Here we demonstrate that RNA-targeting CRISPR effector proteins, a programmable class of gene silencing agents that includes the Cas13 family of enzymes and Cas7–11, can be used to mitigate TDP-43 pathology when programmed to target ataxin-2, a modifier of TDP-43-associated toxicity. In addition to inhibiting the aggregation and transit of TDP-43 to stress granules, we find that the in vivo delivery of an ataxin-2-targeting Cas13 system to a mouse model of TDP-43 proteinopathy improved functional deficits, extended survival, and reduced the severity of neuropathological hallmarks. Further, we benchmark RNA-targeting CRISPR platforms against ataxin-2 and find that high-fidelity forms of Cas13 possess improved transcriptome-wide specificity compared to Cas7–11 and a first-generation effector. Our results demonstrate the potential of CRISPR technology for TDP-43 proteinopathies.
Stretchable surface electromyography electrode array patch for tendon location and muscle injury prevention
Authors: Yang Shuaijian , Cheng Jinhao , Shang Jin , Hang Chen , Qi Jie , Zhong Leni , Rao Qingyan , He Lei , Liu Chenqi , Ding Li , Zhang Mingming , Chakrabarty Samit , Jiang Xingyu
Published: October 2023

Surface electromyography (sEMG) can provide multiplexed information about muscle performance. If current sEMG electrodes are stretchable, arrayed, and able to be used multiple times, they would offer adequate high-quality data for continuous monitoring. The lack of these properties delays the widespread use of sEMG in clinics and in everyday life. Here, we address these constraints by design of an adhesive dry electrode using tannic acid, polyvinyl alcohol, and PEDOT:PSS (TPP). The TPP electrode offers superior stretchability (~200%) and adhesiveness (0.58 N/cm) compared to current electrodes, ensuring stable and long-term contact with the skin for recording (>20 dB; >5 days). In addition, we developed a metal-polymer electrode array patch (MEAP) comprising liquid metal (LM) circuits and TPP electrodes. The MEAP demonstrated better conformability than commercial arrays, resulting in higher signal-to-noise ratio and more stable recordings during muscle movements. Manufactured using scalable screen-printing, these MEAPs feature a completely stretchable material and array architecture, enabling real-time monitoring of muscle stress, fatigue, and tendon displacement. Their potential to reduce muscle and tendon injuries and enhance performance in daily exercise and professional sports holds great promise.
Miniature spatial transcriptomics for studying parasite-endosymbiont relationships at the micro scale
Authors: Sounart Hailey , Voronin Denis , Masarapu Yuvarani , Chung Matthew , Saarenpää Sami , Ghedin Elodie , Giacomello Stefania
Published: October 2023

Several important human infectious diseases are caused by microscale-sized parasitic nematodes like filarial worms. Filarial worms have their own spatial tissue organization; to uncover this tissue structure, we need methods that can spatially resolve these miniature specimens. Most filarial worms evolved a mutualistic association with endosymbiotic bacteria Wolbachia. However, the mechanisms underlying the dependency of filarial worms on the fitness of these bacteria remain unknown. As Wolbachia is essential for the development, reproduction, and survival of filarial worms, we spatially explored how Wolbachia interacts with the worm’s reproductive system by performing a spatial characterization using Spatial Transcriptomics (ST) across a posterior region containing reproductive tissue and developing embryos of adult female Brugia malayi worms. We provide a proof-of-concept for miniature-ST to explore spatial gene expression patterns in small sample types, demonstrating the method’s ability to uncover nuanced tissue region expression patterns, observe the spatial localization of key B. malayi - Wolbachia pathway genes, and co-localize the B. malayi spatial transcriptome in Wolbachia tissue regions, also under antibiotic treatment. We envision our approach will open up new avenues for the study of infectious diseases caused by micro-scale parasitic worms.
Cryptic susceptibility to penicillin/β-lactamase inhibitor combinations in emerging multidrug-resistant, hospital-adapted Staphylococcus epidermidis lineages
Authors: Ba Xiaoliang , Raisen Claire L. , Restif Olivier , Cavaco Lina Maria , Vingsbo Lundberg Carina , Lee Jean Y. H. , Howden Benjamin P. , Bartels Mette D. , Strommenger Birgit , Harrison Ewan M. , Larsen Anders Rhod , Holmes Mark A. , Larsen Jesper
Published: October 2023

Global spread of multidrug-resistant, hospital-adapted Staphylococcus epidermidis lineages underscores the need for new therapeutic strategies. Here we show that many S. epidermidis isolates belonging to these lineages display cryptic susceptibility to penicillin/β-lactamase inhibitor combinations under in vitro conditions, despite carrying the methicillin resistance gene mecA. Using a mouse thigh model of S. epidermidis infection, we demonstrate that single-dose treatment with amoxicillin/clavulanic acid significantly reduces methicillin-resistant S. epidermidis loads without leading to detectable resistance development. On the other hand, we also show that methicillin-resistant S. epidermidis is capable of developing increased resistance to amoxicillin/clavulanic acid during long-term in vitro exposure to these drugs. These findings suggest that penicillin/β-lactamase inhibitor combinations could be a promising therapeutic candidate for treatment of a high proportion of methicillin-resistant S. epidermidis infections, although the in vivo risk of resistance development needs to be further addressed before they can be incorporated into clinical trials.
Metasurface enabled broadband all optical edge detection in visible frequencies
Authors: Tanriover Ibrahim , Dereshgi Sina Abedini , Aydin Koray
Published: October 2023

Image processing is of fundamental importance for numerous modern technologies. In recent years, due to increasing demand for real-time and continuous data processing, metamaterial and metasurface based all-optical computation techniques emerged as a promising alternative to digital computation. Most of the pioneer research focused on all-optical edge detection as a fundamental step of image processing. Metasurfaces have been shown to enable real time edge detection with low to no power consumption. However, the previous demonstrations were subjected to the several limitations such as need for oblique-incidence, polarization dependence, need for additional polarizers, narrow operation bandwidth, being limited with processing in 1D, operation with coherent light only, and requiring digital post-processing. Here, we propose and experimentally demonstrate 2D isotropic, polarization-independent, broadband edge detection with high transmission efficiency under both coherent and incoherent illumination along the visible frequency range using a metasurface based on Fourier optics principles.
Apparent symmetry rising induced by crystallization inhibition in ternary co-crystallization-driven self-assembly
Authors: Xie Siyu , Sun Wenjia , Sun Junliang , Wan Xinhua , Zhang Jie
Published: October 2023

The concept of apparent symmetry rising, opposite to symmetry breaking, was proposed to illustrate the unusual phenomenon that the symmetry of the apparent morphology of the multiply twinned particle is higher than that of its crystal structure. We developed a unique strategy of co-crystallization-driven self-assembly of amphiphilic block copolymers PEO-b-PS and the inorganic cluster silicotungstic acid to achieve apparent symmetry rising of nanoparticles under mild conditions. The triangular nanoplates triply twinned by orthogonal crystals (low symmetry) have an additional triple symmetry (high symmetry). The appropriate crystallization inhibition of short solvophilic segments of the block copolymers favors the oriented attachment of homogeneous domains of hybrid nanoribbons, and consequently forms kinetic-controlled triangular nanoplates with twin grain boundaries.
Oligodendrocyte dynamics dictate cognitive performance outcomes of working memory training in mice
Authors: Shimizu Takahiro , Nayar Stuart G. , Swire Matthew , Jiang Yi , Grist Matthew , Kaller Malte , Sampaio Baptista Cassandra , Bannerman David M. , Johansen-Berg Heidi , Ogasawara Katsutoshi , Tohyama Koujiro , Li Huiliang , Richardson William D.
Published: October 2023

Previous work has shown that motor skill learning stimulates and requires generation of myelinating oligodendrocytes (OLs) from their precursor cells (OLPs) in the brains of adult mice. In the present study we ask whether OL production is also required for non-motor learning and cognition, using T-maze and radial-arm-maze tasks that tax spatial working memory. We find that maze training stimulates OLP proliferation and OL production in the medial prefrontal cortex (mPFC), anterior corpus callosum (genu), dorsal thalamus and hippocampal formation of adult male mice; myelin sheath formation is also stimulated in the genu. Genetic blockade of OL differentiation and neo-myelination inMyrfconditional-knockout mice strongly impairs training-induced improvements in maze performance. We find a strong positive correlation between the performance of individual wild type mice and the scale of OLP proliferation and OL generation during training, but not with the number or intensity of c-Fos+neurons in their mPFC, underscoring the important role played by OL lineage cells in cognitive processing.
Glia instruct axon regeneration via a ternary modulation of neuronal calcium channels in Drosophila
Authors: Trombley Shannon , Powell Jackson , Guttipatti Pavithran , Matamoros Andrew , Lin Xiaohui , O’Harrow Tristan , Steinschaden Tobias , Miles Leann , Wang Qin , Wang Shuchao , Qiu Jingyun , Li Qingyang , Li Feng , Song Yuanquan
Published: October 2023

A neuron’s regenerative capacity is governed by its intrinsic and extrinsic environment. Both peripheral and central neurons exhibit cell-type-dependent axon regeneration, but the underlying mechanism is unclear. Glia provide a milieu essential for regeneration. However, the routes of glia-neuron signaling remain underexplored. Here, we show that regeneration specificity is determined by the axotomy-induced Ca2+ transients only in the fly regenerative neurons, which is mediated by L-type calcium channels, constituting the core intrinsic machinery. Peripheral glia regulate axon regeneration via a three-layered and balanced modulation. Glia-derived tumor necrosis factor acts through its neuronal receptor to maintain calcium channel expression after injury. Glia sustain calcium channel opening by enhancing membrane hyperpolarization via the inwardly-rectifying potassium channel (Irk1). Glia also release adenosine which signals through neuronal adenosine receptor (AdoR) to activate HCN channels (Ih) and dampen Ca2+ transients. Together, we identify a multifaceted glia-neuron coupling which can be hijacked to promote neural repair.
KDM2B regulates hippocampal morphogenesis by transcriptionally silencing Wnt signaling in neural progenitors
Authors: Zhang Bo , Zhao Chen , Shen Wenchen , Li Wei , Zheng Yue , Kong Xiangfei , Wang Junbao , Wu Xudong , Zeng Tao , Liu Ying , Zhou Yan
Published: October 2023

The hippocampus plays major roles in learning and memory, and its formation requires precise coordination of patterning, cell proliferation, differentiation, and migration. Here we removed the chromatin-association capability of KDM2B in the progenitors of developing dorsal telencephalon (Kdm2b∆CxxC) to discover thatKdm2b∆CxxChippocampus, particularly the dentate gyrus, became drastically smaller with disorganized cellular components and structure.Kdm2b∆CxxCmice display prominent defects in spatial memory, motor learning and fear conditioning, resembling patients withKDM2Bmutations. The migration and differentiation of neural progenitor cells is greatly impeded in the developingKdm2b∆CxxChippocampus. Mechanism studies reveal that Wnt signaling genes in developingKdm2b∆CxxChippocampi are de-repressed due to reduced enrichment of repressive histone marks by polycomb repressive complexes. Activating the Wnt signaling disturbs hippocampal neurogenesis, recapitulating the effect of KDM2B loss. Together, we unveil a previously unappreciated gene repressive program mediated by KDM2B that controls progressive fate specifications and cell migration, hence morphogenesis of the hippocampus.
A robust yeast biocontainment system with two-layered regulation switch dependent on unnatural amino acid
Authors: Chang Tiantian , Ding Weichao , Yan Shirui , Wang Yun , Zhang Haoling , Zhang Yu , Ping Zhi , Zhang Huiming , Huang Yijian , Zhang Jiahui , Wang Dan , Zhang Wenwei , Xu Xun , Shen Yue , Fu Xian
Published: October 2023

Synthetic auxotrophy in which cell viability depends on the presence of an unnatural amino acid (unAA) provides a powerful strategy to restrict unwanted propagation of genetically modified organisms (GMOs) in open environments and potentially prevent industrial espionage. Here, we describe a generic approach for robust biocontainment of budding yeast dependent on unAA. By understanding escape mechanisms, we specifically optimize our strategies by introducing designed “immunity” to the generation of amber-suppressor tRNAs and developing the transcriptional- and translational-based biocontainment switch. We further develop a fitness-oriented screening method to easily obtain multiplex safeguard strains that exhibit robust growth and undetectable escape frequency (<~10−9) on solid media for 14 days. Finally, we show that employing our multiplex safeguard system could restrict the proliferation of strains of interest in a real fermentation scenario, highlighting the great potential of our yeast biocontainment strategy to protect the industrial proprietary strains.
Native microbiome dominates over host factors in shaping the probiotic genetic evolution in the gut
Authors: Jiang Shuaiming , Zhang Chengcheng , Han Zhe , Ma Wenyao , Wang Shunhe , Huo Dongxue , Cui Weipeng , Zhai Qixiao , Huang Shi , Zhang Jiachao
Published: October 2023

Probiotics often acquire potentially adaptive mutations in vivo, gaining new functional traits through gut selection. While both the host and microbiome can contribute to probiotics’ genetic evolution, separating the microbiome and the host’s contribution to such selective pressures remains challenging. Here, we introduced germ-free (GF) and specific pathogen-free (SPF) mouse models to track how probiotic strains, i.e., Lactiplantibacillus plantarum HNU082 (Lp082) and Bifidobacterium animalis subsp. lactis V9 (BV9), genetically evolved under selection pressures derived from host factors alone and both host and microbial ecological factors. Notably, compared to the genome of a probiotic strain before consumption, the host only elicited <15 probiotic mutations in probiotic genomes that emerged in the luminal environment of GF mice, while a total of 840 mutations in Lp082 mutants and 21,579 mutations in BV9 were found in SPF mice, <0.25% of those derived from both factors that were never captured by other experimental evolution studies, indicating that keen microbial competitions exhibited the predominant evolutionary force in shaping probiotic genetic composition (>99.75%). For a given probiotic, functional genes occurring in potentially adaptive mutations induced by hosts (GF mice) were all shared with those found in mutants of SPF mice. Collectively, the native microbiome consistently drove a more rapid and divergent genetic evolution of probiotic strains in seven days of colonization than host factors did. Our study further laid a theoretical foundation for genetically engineering probiotics for better gut adaptation through in vitro artificial gut ecosystems without the selection pressures derived from host factors.
The best thermoelectrics revisited in the quantum limit
Authors: Ding Sifan , Chen Xiaobin , Xu Yong , Duan Wenhui
Published: October 2023

The classical problem of best thermoelectrics, which was believed originally solved by Mahan and Sofo [Proc. Natl. Acad. Sci. USA 93, 7436 (1996)], is revisited and discussed in the quantum limit. We express the thermoelectric figure of merit (zT) as a functional of electronic transmission probability $${{{\mathcal{T}}}}$$
T
by the Landauer–Büttiker formalism, which is able to deal with thermoelectric transport ranging from ballistic to diffusive regimes. We also propose to apply the calculus of variations to search for the optimal $${{{\mathcal{T}}}}$$
T
giving the maximal zT. Our study reveals that the optimal transmission probability $${{{\mathcal{T}}}}$$
T
is a boxcar function instead of a delta function proposed by Mahan and Sofo, leading to zT exceeding the well-known Mahan–Sofo limit. Furthermore, we suggest realizing the optimal $${{{\mathcal{T}}}}$$
T
in topological material systems. Our work defines the theoretical upper limit for quantum thermoelectrics, which is of fundamental significance to the future development of thermoelectrics.
High-throughput deformation potential and electrical transport calculations
Authors: Jin Yeqing , Wang Xiangdong , Yao Mingjia , Qiu Di , Singh David J. , Xi Jinyang , Yang Jiong , Xi Lili
Published: October 2023

The deformation potential plays an important role in electrical transport properties, but in the context of high-throughput searches requires a consistent and readily computable reference level. Here, we design a high-throughput method for calculating the deformation potential for semiconductors in the MatHub-3d database. The deformation potential is obtained from the volume-dependent band edge (valence band maximum and conduction band minimum) variations with respect to the reference level. In order to adapt the calculation of reference level to a high-throughput manner, the average value of the first valence electron energy band associated with each compound is used as the reference level. Deformation potentials for 11,993 materials are calculated using the above-mentioned method. By considering the calculated deformation potentials, electronic structures, and bulk moduli, 9957 compounds with converged electrical transport properties are obtained. 332 promising p-type thermoelectric materials, and 321 n-type entries are then proposed. Among them, 156 compounds are screened to having both potentially good n- and p-type thermoelectric transport properties. The band structures and chemical bonding information for several typical compounds are further presented to reveal favorable band and bonding features for thermoelectrics.
Exploring high thermal conductivity polymers via interpretable machine learning with physical descriptors
Authors: Huang Xiang , Ma Shengluo , Zhao C. Y. , Wang Hong , Ju Shenghong
Published: October 2023

The efficient and economical exploitation of polymers with high thermal conductivity (TC) is essential to solve the issue of heat dissipation in organic devices. Currently, the experimental preparation of functional polymers with high TC remains a trial-and-error process due to the multi-degrees of freedom during the synthesis and characterization process. Polymer informatics equips machine learning (ML) as a powerful engine for the efficient design of polymers with desired properties. However, available polymer TC databases are rare, and establishing appropriate polymer representation is still challenging. In this work, we propose a high-throughput screening framework for polymer chains with high TC via interpretable ML and physical feature engineering. The hierarchical down-selection process stepwise optimizes the 320 initial physical descriptors to the final 20 dimensions and then assists the ML models to achieve a prediction accuracyR2over 0.80, which is superior to traditional graph descriptors. Further, we analyze the contribution of the individual descriptors to TC and derive the explicit equation for TC prediction using symbolic regression. The high TC polymer structures are mostly π-conjugated, whose overlapping p-orbitals enable easy maintenance of strong chain stiffness and large group velocities. Ultimately, we establish the connections between the individual chains and the amorphous state of polymers. Polymer chains with high TC have strong intra-chain interactions, and their corresponding amorphous systems are favorable for obtaining a large radius of gyration and causing enhanced thermal transport. The proposed data-driven framework should facilitate the theoretical and experimental design of polymers with desirable properties.
Investigating molybdenum’s sulphur scavenging ability for MoS2 formation in preventing pitting corrosion of stainless steels
Authors: Kuah Kai Xiang , Blackwood Daniel J.
Published: October 2023

The addition of Mo enhances pitting corrosion resistance in 304L stainless steel. However, there is no consensus on the underlying mechanism. One possible explanation is that molybdenum converts sulfide to stable MoS2. This study investigates the effect of MoS2 inclusion on the corrosion of 304L stainless steel by introducing both MnS and MoS2 using spark plasma sintering. The reduction of MoS2 to Mo is observed during the sintering process, contradicting the assumption that the sulfide inclusions can be stabilised by forming MoS2. Therefore, MoS2 formation cannot explain the improved corrosion resistance of 304L stainless steel with the addition of Mo.
Clinical inertia in asthma
Authors: Fukuda Yosuke , Homma Tetsuya , Sagara Hironori
Published: October 2023

Despite advances in pharmaceutical treatment in recent years, a relatively high proportion of patients with asthma do not have adequate asthma control, causing chronic disability, poor quality of life, and multiple emergency department visits and hospitalizations. A multifaceted approach is needed to overcome the problems with managing asthma, and clinical inertia (CI) is a crucial concept to assist with this approach. It divides clinical inertia into three main categories, which include healthcare provider-related, patient-related, and healthcare system-related CI. The strategies to overcome these CI are complex, and the M-GAP approach, which combines a multidisciplinary approach, dissemination of guidelines, utilization of applications, and development and promotion of low-cost prescriptions, will help clinicians.
Requirements for a processing-node quantum repeater on a real-world fiber grid
Authors: Avis Guus , Ferreira da Silva Francisco , Coopmans Tim , Dahlberg Axel , Jirovská Hana , Maier David , Rabbie Julian , Torres-Knoop Ariana , Wehner Stephanie
Published: October 2023

We numerically study the distribution of entanglement between the Dutch cities of Delft and Eindhoven realized with a processing-node quantum repeater and determine minimal hardware requirements for verifiable blind quantum computation using color centers and trapped ions. Our results are obtained considering restrictions imposed by a real-world fiber grid and using detailed hardware-specific models. By comparing our results to those we would obtain in idealized settings, we show that simplifications lead to a distorted picture of hardware demands, particularly on memory coherence and photon collection. We develop general machinery suitable for studying arbitrary processing-node repeater chains using NetSquid, a discrete-event simulator for quantum networks. This enables us to include time-dependent noise models and simulate repeater protocols with cut-offs, including the required classical control communication. We find minimal hardware requirements by solving an optimization problem using genetic algorithms on a high-performance-computing cluster. Our work provides guidance for further experimental progress, and showcases limitations of studying quantum-repeater requirements in idealized situations.
Awakening the natural capability of psicose production in Escherichia coli
Authors: Taylor Jayce E. , Palur Dileep Sai Kumar , Zhang Angela , Gonzales Jake N. , Arredondo Augustine , Coulther Timothy A. , Lechner Amiruddin Bin Johan , Rodriguez Elys P. , Fiehn Oliver , Didzbalis John , Siegel Justin B. , Atsumi Shota
Published: October 2023

Due to the rampant rise in obesity and diabetes, consumers are desperately seeking for ways to reduce their sugar intake, but to date there are no options that are both accessible and without sacrifice of palatability. One of the most promising new ingredients in the food system as a non-nutritive sugar substitute with near perfect palatability is D-psicose. D-psicose is currently produced using an in vitro enzymatic isomerization of D-fructose, resulting in low yield and purity, and therefore requiring substantial downstream processing to obtain a high purity product. This has made adoption of D-psicose into products limited and results in significantly higher per unit costs, reducing accessibility to those most in need. Here, we found that Escherichia coli natively possesses a thermodynamically favorable pathway to produce D-psicose from D-glucose through a series of phosphorylation-epimerization-dephosphorylation steps. To increase carbon flux towards D-psicose production, we introduced a series of genetic modifications to pathway enzymes, central carbon metabolism, and competing metabolic pathways. In an attempt to maximize both cellular viability and D-psicose production, we implemented methods for the dynamic regulation of key genes including clustered regularly interspaced short palindromic repeats inhibition (CRISPRi) and stationary-phase promoters. The engineered strains achieved complete consumption of D-glucose and production of D-psicose, at a titer of 15.3 g L-1, productivity of 2 g L-1 h-1, and yield of 62% under test tube conditions. These results demonstrate the viability of whole-cell catalysis as a sustainable alternative to in vitro enzymatic synthesis for the accessible production of D-psicose.
Spatiotemporal estimation of nutrient data from the northwest pacific and east asian seas
Authors: Lee Gi Seop , Lee Jung Ho , Cho Hong Yeon
Published: October 2023

Nutrient data obtained from field observations have the potential to enhance our understanding of oceanic biogeochemical cycling and productivity changes. In particular, long-term nutrient data can provide valuable information on the links between climate change and biogeochemical changes. However, unlike other observational variables such as sea surface temperature, nutrient data are limited in terms of their broad-scale observations and automated sensor-based measurements. In this study, we analyzed nitrate and phosphate data obtained from coastal regions in Northeast Asia and the northwest Pacific from 1980 to 2019 using the spatiotemporal kriging technique and provide results in a spatiotemporal grid format. The data are available at monthly intervals and may be attractive to researchers in the fields of oceanography, marine ecology, and marine biogeochemistry at the climate change scale. Furthermore, sharing the source code of the data production process can contribute to better long-term data reproduction in the future.
Biochemical data documenting variations in mucilage polysaccharides in a range of glycosyltransferase mutants
Authors: Aoi Yuki , Benamar Abdelilah , Saulnier Luc , Ralet Marie-Christine , North Helen M.
Published: October 2023

During Arabidopsis seed coat development, copious amounts of mucilage polysaccharides are produced in the epidermal cells. When hydrated on imbibition, these polysaccharides expand and are released to encapsulate the seed as a two-layered hydrogel. Polysaccharides are synthesized from UDP-sugars by glycosyltransferases (GTs) and several GTs, with differing activities, have been identified that contribute to mucilage polysaccharide synthesis. How these GTs orchestrate production of the complex polysaccharides found in mucilage remains to be determined. In this study, we generated a range of multiple GT mutants using either CRISPR/Cas9 targeted mutation or genetic crosses of existing T-DNA insertion mutants. Four traits for mucilage amounts or macromolecular properties were examined for four replicate seed lots from 31 different GT mutant combinations. This data provides a valuable resource for future genetic, biochemical, structural, and functional studies of the roles and properties of polysaccharides present in Arabidopsis mucilage and the relative contributions of different GTs to mucilage production.