bluuebunny/crossref_metadata_2025_split huggingface dataset:
Normal-to-topological insulator martensitic phase transition in group-IV monochalcogenides driven by light
Authors: Zhou Jian , Zhang Shunhong , Li Ju 
Published: January 2020

AbstractA material potentially exhibiting multiple crystalline phases with distinct optoelectronic properties can serve as a phase-change memory material. The sensitivity and kinetics can be enhanced when the two competing phases have large electronic structure contrast and the phase change process is diffusionless and martensitic. In this work, we theoretically and computationally illustrate that such a phase transition could occur in the group-IV monochalcogenide SnSe compound, which can exist in the quantum topologically trivial Pnma-SnSe and nontrivial $$Fm\bar 3m$$

F
m

3

¯

m

-SnSe phases. Furthermore, owing to the electronic band structure differences of these phases, a large contrast in the optical responses in the THz region is revealed. According to the thermodynamic theory for a driven dielectric medium, optomechanical control to trigger a topological phase transition using a linearly polarized laser with selected frequency, power and pulse duration is proposed. We further estimate the critical optical electric field to drive a barrierless transition that can occur on the picosecond timescale. This light actuation strategy does not require fabrication of mechanical contacts or electrical leads and only requires transparency. We predict that an optically driven phase transition accompanied by a large entropy difference can be used in an “optocaloric” cooling device.
Surface enhanced Raman scattering artificial nose for high dimensionality fingerprinting
Authors: Kim Nayoung , Thomas Michael R. , Bergholt Mads S. , Pence Isaac J. , Seong Hyejeong , Charchar Patrick , Todorova Nevena , Nagelkerke Anika , Belessiotis-Richards Alexis , Payne David J. , Gelmi Amy , Yarovsky Irene , Stevens Molly M. 
Published: January 2020

AbstractLabel-free surface-enhanced Raman spectroscopy (SERS) can interrogate systems by directly fingerprinting their components’ unique physicochemical properties. In complex biological systems however, this can yield highly overlapping spectra that hinder sample identification. Here, we present an artificial-nose inspired SERS fingerprinting approach where spectral data is obtained as a function of sensor surface chemical functionality. Supported by molecular dynamics modeling, we show that mildly selective self-assembled monolayers can influence the strength and configuration in which analytes interact with plasmonic surfaces, diversifying the resulting SERS fingerprints. Since each sensor generates a modulated signature, the implicit value of increasing the dimensionality of datasets is shown using cell lysates for all possible combinations of up to 9 fingerprints. Reliable improvements in mean discriminatory accuracy towards 100% are achieved with each additional surface functionality. This arrayed label-free platform illustrates the wide-ranging potential of high-dimensionality artificial-nose based sensing systems for more reliable assessment of complex biological matrices.
Directional Goldstone waves in polariton condensates close to equilibrium
Authors: Ballarini Dario , Caputo Davide , Dagvadorj Galbadrakh , Juggins Richard , Giorgi Milena De , Dominici Lorenzo , West Kenneth , Pfeiffer Loren N. , Gigli Giuseppe , Szymańska Marzena H. , Sanvitto Daniele 
Published: January 2020

AbstractQuantum fluids of light are realized in semiconductor microcavities using exciton-polaritons, solid-state quasi-particles with a light mass and sizeable interactions. Here, we use the microscopic analogue of oceanographic techniques to measure the excitation spectrum of a thermalised polariton condensate. Increasing the fluid density, we demonstrate the transition from a free-particle parabolic dispersion to a linear, sound-like Goldstone mode characteristic of superfluids at equilibrium. Notably, we reveal the effect of an asymmetric pumping by showing that collective excitations are created with a definite direction with respect to the condensate. Furthermore, we measure the critical sound speed for polariton superfluids close to equilibrium.
Physical and virtual carbon metabolism of global cities
Authors: Chen Shaoqing , Chen Bin , Feng Kuishuang , Liu Zhu , Fromer Neil , Tan Xianchun , Alsaedi Ahmed , Hayat Tasawar , Weisz Helga , Schellnhuber Hans Joachim , Hubacek Klaus 
Published: January 2020

AbstractUrban activities have profound and lasting effects on the global carbon balance. Here we develop a consistent metabolic approach that combines two complementary carbon accounts, the physical carbon balance and the fossil fuel-derived gaseous carbon footprint, to track carbon coming into, being added to urban stocks, and eventually leaving the city. We find that over 88% of the physical carbon in 16 global cities is imported from outside their urban boundaries, and this outsourcing of carbon is notably amplified by virtual emissions from upstream activities that contribute 33–68% to their total carbon inflows. While 13–33% of the carbon appropriated by cities is immediately combusted and released as CO2, between 8 and 24% is stored in durable household goods or becomes part of other urban stocks. Inventorying carbon consumed and stored for urban metabolism should be given more credit for the role it can play in stabilizing future global climate.
Clonal kinetics and single-cell transcriptional profiling of CAR-T cells in patients undergoing CD19 CAR-T immunotherapy
Authors: Sheih Alyssa , Voillet Valentin , Hanafi Laïla-Aïcha , DeBerg Hannah A. , Yajima Masanao , Hawkins Reed , Gersuk Vivian , Riddell Stanley R. , Maloney David G. , Wohlfahrt Martin E. , Pande Dnyanada , Enstrom Mark R. , Kiem Hans-Peter , Adair Jennifer E. , Gottardo Raphaël , Linsley Peter S. , Turtle Cameron J. 
Published: January 2020

AbstractChimeric antigen receptor (CAR) T-cell therapy has produced remarkable anti-tumor responses in patients with B-cell malignancies. However, clonal kinetics and transcriptional programs that regulate the fate of CAR-T cells after infusion remain poorly understood. Here we perform TCRB sequencing, integration site analysis, and single-cell RNA sequencing (scRNA-seq) to profile CD8+ CAR-T cells from infusion products (IPs) and blood of patients undergoing CD19 CAR-T immunotherapy. TCRB sequencing shows that clonal diversity of CAR-T cells is highest in the IPs and declines following infusion. We observe clones that display distinct patterns of clonal kinetics, making variable contributions to the CAR-T cell pool after infusion. Although integration site does not appear to be a key driver of clonal kinetics, scRNA-seq demonstrates that clones that expand after infusion mainly originate from infused clusters with higher expression of cytotoxicity and proliferation genes. Thus, we uncover transcriptional programs associated with CAR-T cell behavior after infusion.
Discovery of bilaterian-type through-guts in cloudinomorphs from the terminal Ediacaran Period
Authors: Schiffbauer James D. , Selly Tara , Jacquet Sarah M. , Merz Rachel A. , Nelson Lyle L. , Strange Michael A. , Cai Yaoping , Smith Emily F. 
Published: January 2020

AbstractThe fossil record of the terminal Ediacaran Period is typified by the iconic index fossil Cloudina and its relatives. These tube-dwellers are presumed to be primitive metazoans, but resolving their phylogenetic identity has remained a point of contention. The root of the problem is a lack of diagnostic features; that is, phylogenetic interpretations have largely centered on the only available source of information—their external tubes. Here, using tomographic analyses of fossils from the Wood Canyon Formation (Nevada, USA), we report evidence of recognizable soft tissues within their external tubes. Although alternative interpretations are plausible, these internal cylindrical structures may be most appropriately interpreted as digestive tracts, which would be, to date, the earliest-known occurrence of such features in the fossil record. If this interpretation is correct, their nature as one-way through-guts not only provides evidence for establishing these fossils as definitive bilaterians but also has implications for the long-debated phylogenetic position of the broader cloudinomorphs.
PHD1 controls muscle mTORC1 in a hydroxylation-independent manner by stabilizing leucyl tRNA synthetase
Authors: D’Hulst Gommaar , Soro-Arnaiz Inés , Masschelein Evi , Veys Koen , Fitzgerald Gillian , Smeuninx Benoit , Kim Sunghoon , Deldicque Louise , Blaauw Bert , Carmeliet Peter , Breen Leigh , Koivunen Peppi , Zhao Shi-Min , De Bock Katrien 
Published: January 2020

AbstractmTORC1 is an important regulator of muscle mass but how it is modulated by oxygen and nutrients is not completely understood. We show that loss of the prolyl hydroxylase domain isoform 1 oxygen sensor in mice (PHD1KO) reduces muscle mass. PHD1KO muscles show impaired mTORC1 activation in response to leucine whereas mTORC1 activation by growth factors or eccentric contractions was preserved. The ability of PHD1 to promote mTORC1 activity is independent of its hydroxylation activity but is caused by decreased protein content of the leucyl tRNA synthetase (LRS) leucine sensor. Mechanistically, PHD1 interacts with and stabilizes LRS. This interaction is promoted during oxygen and amino acid depletion and protects LRS from degradation. Finally, elderly subjects have lower PHD1 levels and LRS activity in muscle from aged versus young human subjects. In conclusion, PHD1 ensures an optimal mTORC1 response to leucine after episodes of metabolic scarcity.
Highly efficient all-inorganic perovskite solar cells with suppressed non-radiative recombination by a Lewis base
Authors: Wang Jing , Zhang Jie , Zhou Yingzhi , Liu Hongbin , Xue Qifan , Li Xiaosong , Chueh Chu-Chen , Yip Hin-Lap , Zhu Zonglong , Jen Alex K. Y. 
Published: January 2020

AbstractAll-inorganic perovskite solar cells (PVSCs) have drawn increasing attention because of their outstanding thermal stability. However, their performance is still inferior than the typical organic-inorganic counterparts, especially for the devices with p-i-n configuration. Herein, we successfully employ a Lewis base small molecule to passivate the inorganic perovskite film, and its derived PVSCs achieved a champion efficiency of 16.1% and a certificated efficiency of 15.6% with improved photostability, representing the most efficient inverted all-inorganic PVSCs to date. Our studies reveal that the nitrile (C-N) groups on the small molecule effectively reduce the trap density of the perovskite film and thus significantly suppresses the non-radiative recombination in the derived PVSC by passivating the Pb-exposed surface, resulting in an improved open-circuit voltage from 1.10 V to 1.16 V after passivation. This work provides an insight in the design of functional interlayers for improving efficiencies and stability of all-inorganic PVSCs.
O-GlcNAc transferase inhibits visceral fat lipolysis and promotes diet-induced obesity
Authors: Yang Yunfan , Fu Minnie , Li Min-Dian , Zhang Kaisi , Zhang Bichen , Wang Simeng , Liu Yuyang , Ni Weiming , Ong Qunxiang , Mi Jia , Yang Xiaoyong 
Published: January 2020

AbstractExcessive visceral fat accumulation is a primary risk factor for metabolically unhealthy obesity and related diseases. The visceral fat is highly susceptible to the availability of external nutrients. Nutrient flux into the hexosamine biosynthetic pathway leads to protein posttranslational modification byO-linked β-N-acetylglucosamine (O-GlcNAc) moieties.O-GlcNAc transferase (OGT) is responsible for the addition of GlcNAc moieties to target proteins. Here, we report that inducible deletion of adipose OGT causes a rapid visceral fat loss by specifically promoting lipolysis in visceral fat. Mechanistically, visceral fat maintains a high level ofO-GlcNAcylation during fasting. Loss of OGT decreasesO-GlcNAcylation of lipid droplet-associated perilipin 1 (PLIN1), which leads to elevated PLIN1 phosphorylation and enhanced lipolysis. Moreover, adipose OGT overexpression inhibits lipolysis and promotes diet-induced obesity. These findings establish an essential role for OGT in adipose tissue homeostasis and indicate a unique potential for targetingO-GlcNAc signaling in the treatment of obesity.
A transcriptome-wide Mendelian randomization study to uncover tissue-dependent regulatory mechanisms across the human phenome
Authors: Richardson Tom G. , Hemani Gibran , Gaunt Tom R. , Relton Caroline L. , Davey Smith George 
Published: January 2020

AbstractDeveloping insight into tissue-specific transcriptional mechanisms can help improve our understanding of how genetic variants exert their effects on complex traits and disease. In this study, we apply the principles of Mendelian randomization to systematically evaluate transcriptome-wide associations between gene expression (across 48 different tissue types) and 395 complex traits. Our findings indicate that variants which influence gene expression levels in multiple tissues are more likely to influence multiple complex traits. Moreover, detailed investigations of our results highlight tissue-specific associations, drug validation opportunities, insight into the likely causal pathways for trait-associated variants and also implicate putative associations at loci yet to be implicated in disease susceptibility. Similar evaluations can be conducted at http://mrcieu.mrsoftware.org/Tissue_MR_atlas/.
Edge stabilization in reduced-dimensional perovskites
Authors: Na Quan Li , Ma Dongxin , Zhao Yongbiao , Voznyy Oleksandr , Yuan Haifeng , Bladt Eva , Pan Jun , García de Arquer F. Pelayo , Sabatini Randy , Piontkowski Zachary , Emwas Abdul-Hamid , Todorović Petar , Quintero-Bermudez Rafael , Walters Grant , Fan James Z. , Liu Mengxia , Tan Hairen , Saidaminov Makhsud I. , Gao Liang , Li Yiying , Anjum Dalaver H. , Wei Nini , Tang Jiang , McCamant David W. , Roeffaers Maarten B. J. , Bals Sara , Hofkens Johan , Bakr Osman M. , Lu Zheng-Hong , Sargent Edward H. 
Published: January 2020

AbstractReduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite light-emitting diodes is their limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack is powered by photogenerated and electrically-injected carriers that diffuse to the nanoplatelet edges and produce superoxide. We report an edge-stabilization strategy wherein phosphine oxides passivate unsaturated lead sites during perovskite crystallization. With this approach, we synthesize reduced-dimensional perovskites that exhibit 97 ± 3% photoluminescence quantum yields and stabilities that exceed 300 h upon continuous illumination in an air ambient. We achieve green-emitting devices with a peak external quantum efficiency (EQE) of 14% at 1000 cd m−2; their maximum luminance is 4.5 × 104 cd m−2 (corresponding to an EQE of 5%); and, at 4000 cd m−2, they achieve an operational half-lifetime of 3.5 h.
Structural basis of liprin-α-promoted LAR-RPTP clustering for modulation of phosphatase activity
Authors: Xie Xingqiao , Luo Ling , Liang Mingfu , Zhang Wenchao , Zhang Ting , Yu Cong , Wei Zhiyi 
Published: January 2020

AbstractLeukocyte common antigen-related receptor protein tyrosine phosphatases (LAR-RPTPs) are cell adhesion molecules involved in mediating neuronal development. The binding of LAR-RPTPs to extracellular ligands induces local clustering of LAR-RPTPs to regulate axon growth and synaptogenesis. LAR-RPTPs interact with synaptic liprin-α proteins via the two cytoplasmic phosphatase domains, D1 and D2. Here we solve the crystal structure of LAR_D1D2 in complex with the SAM repeats of liprin-α3, uncovering a conserved two-site binding mode. Cellular analysis shows that liprin-αs robustly promote clustering of LAR in cells by both the liprin-α/LAR interaction and the oligomerization of liprin-α. Structural analysis reveals a unique homophilic interaction of LAR via the catalytically active D1 domains. Disruption of the D1/D1 interaction diminishes the liprin-α-promoted LAR clustering and increases tyrosine dephosphorylation, demonstrating that the phosphatase activity of LAR is negatively regulated by forming clusters. Additionally, we find that the binding of LAR to liprin-α allosterically regulates the liprin-α/liprin-β interaction.
Macropinocytosis drives T cell growth by sustaining the activation of mTORC1
Authors: Charpentier John C. , Chen Di , Lapinski Philip E. , Turner Jackson , Grigorova Irina , Swanson Joel A. , King Philip D. 
Published: January 2020

AbstractMacropinocytosis is an evolutionarily-conserved, large-scale, fluid-phase form of endocytosis that has been ascribed different functions including antigen presentation in macrophages and dendritic cells, regulation of receptor density in neurons, and regulation of tumor growth under nutrient-limiting conditions. However, whether macropinocytosis regulates the expansion of non-transformed mammalian cells is unknown. Here we show that primary mouse and human T cells engage in macropinocytosis that increases in magnitude upon T cell activation to support T cell growth even under amino acid (AA) replete conditions. Mechanistically, macropinocytosis in T cells provides access of extracellular AA to an endolysosomal compartment to sustain activation of the mechanistic target of rapamycin complex 1 (mTORC1) that promotes T cell growth. Our results thus implicate a function of macropinocytosis in mammalian cell growth beyond Ras-transformed tumor cells via sustained mTORC1 activation.
Reversible manipulation of the magnetic state in SrRuO3 through electric-field controlled proton evolution
Authors: Li Zhuolu , Shen Shengchun , Tian Zijun , Hwangbo Kyle , Wang Meng , Wang Yujia , Bartram F. Michael , He Liqun , Lyu Yingjie , Dong Yongqi , Wan Gang , Li Haobo , Lu Nianpeng , Zang Jiadong , Zhou Hua , Arenholz Elke , He Qing , Yang Luyi , Luo Weidong , Yu Pu 
Published: January 2020

AbstractIonic substitution forms an essential pathway to manipulate the structural phase, carrier density and crystalline symmetry of materials via ion-electron-lattice coupling, leading to a rich spectrum of electronic states in strongly correlated systems. Using the ferromagnetic metal SrRuO3 as a model system, we demonstrate an efficient and reversible control of both structural and electronic phase transformations through the electric-field controlled proton evolution with ionic liquid gating. The insertion of protons results in a large structural expansion and increased carrier density, leading to an exotic ferromagnetic to paramagnetic phase transition. Importantly, we reveal a novel protonated compound of HSrRuO3 with paramagnetic metallic as ground state. We observe a topological Hall effect at the boundary of the phase transition due to the proton concentration gradient across the film-depth. We envision that electric-field controlled protonation opens up a pathway to explore novel electronic states and material functionalities in protonated material systems.
Phase-coherent lightwave communications with frequency combs
Authors: Lundberg Lars , Mazur Mikael , Mirani Ali , Foo Benjamin , Schröder Jochen , Torres-Company Victor , Karlsson Magnus , Andrekson Peter A. 
Published: January 2020

AbstractFiber-optical networks are a crucial telecommunication infrastructure in society. Wavelength division multiplexing allows for transmitting parallel data streams over the fiber bandwidth, and coherent detection enables the use of sophisticated modulation formats and electronic compensation of signal impairments. Optical frequency combs can replace the multiple lasers used for the different wavelength channels. Beyond multiplexing, it has been suggested that the broadband phase coherence of frequency combs could simplify the receiver scheme by performing joint reception and processing of several wavelength channels, but an experimental validation in a fiber transmission experiment remains elusive. Here we demonstrate and quantify joint reception and processing of several wavelength channels in a full transmission system. We demonstrate two joint processing schemes; one that reduces the phase-tracking complexity and one that increases the transmission performance.
An electrochemical biosensor for the detection of epithelial-mesenchymal transition
Authors: Du Xin , Zhang Zhenhua , Zheng Xiaodi , Zhang Hongyan , Dong Dan , Zhang Zhenguo , Liu Min , Zhou Jun 
Published: January 2020

AbstractEpithelial-mesenchymal transition (EMT) is critically involved in a variety of biological processes. Electrochemical sensing offers potential to develop more effective technology for EMT detection. In this study, by using the unique performance of quantum dot (QD)-nanocomposite materials, we establish an electrochemical biosensor that can specifically detect the change of E-cadherin and analyze different stages of EMT. The signal for EMT is largely magnified due to the transmission of molecular information to the electronic device. In addition, differential pulse voltammetry reveals that the response of the electrochemical signals is rapid and sensitive, due to the synergistic effect of QDs and carbon nanotube-gold nanoparticles. Our study thus suggests that electrochemical sensing is an effective technology for detecting EMT and may have broad applications in analyzing various cell type transitions.
Structural basis for adhesion G protein-coupled receptor Gpr126 function
Authors: Leon Katherine , Cunningham Rebecca L. , Riback Joshua A. , Feldman Ezra , Li Jingxian , Sosnick Tobin R. , Zhao Minglei , Monk Kelly R. , Araç Demet 
Published: January 2020

AbstractMany drugs target the extracellular regions (ECRs) of cell-surface receptors. The large and alternatively-spliced ECRs of adhesion G protein-coupled receptors (aGPCRs) have key functions in diverse biological processes including neurodevelopment, embryogenesis, and tumorigenesis. However, their structures and mechanisms of action remain unclear, hampering drug development. The aGPCR Gpr126/Adgrg6 regulates Schwann cell myelination, ear canal formation, and heart development; and GPR126 mutations cause myelination defects in human. Here, we determine the structure of the complete zebrafish Gpr126 ECR and reveal five domains including a previously unknown domain. Strikingly, the Gpr126 ECR adopts a closed conformation that is stabilized by an alternatively spliced linker and a conserved calcium-binding site. Alternative splicing regulates ECR conformation and receptor signaling, while mutagenesis of the calcium-binding site abolishes Gpr126 function in vivo. These results demonstrate that Gpr126 ECR utilizes a multi-faceted dynamic approach to regulate receptor function and provide relevant insights for ECR-targeted drug design.