bluuebunny/crossref_metadata_2025 huggingface dataset:
A Persistent Depletion of Plasma Ions Within Jupiter's Auroral Polar Caps
Authors: Pollock C. J. , Ebert R. W. , Allegrini F. , Bagenal F. , McComas D. J. , Szalay J. R. , Valek P.
Published: November 2020

Regions poleward of Jupiter's main auroral ovals are largely devoid of 0.01 to 46 keV/q ions. We report ion measurements from the plasma instrument on the Juno spacecraft in polar orbit around Jupiter that characterize the presence or absence of structured ion fluxes poleward of the main ovals. We approximate geometric centers of published north and south Jovian main ovals and develop a probability metric for observation of plasma ions as a function of angular distance from these centers to the magnetic foot points of the observations, in the north and south separately. Using data from Juno's first 26 perijoves, at Jovicentric distances of 1.06 to 12 RJ, this metric shows a systematic decrease within both north and south main ovals, in the probability of observing plasma ions as the chosen centers are approached. This is consistent with previous reports of large electrostatic potential drops above Jupiter's polar caps.
Inferring Florida Current Volume Transport From Satellite Altimetry
Authors: Volkov Denis L. , Domingues Ricardo , Meinen Christopher S. , Garcia Rigoberto , Baringer Molly , Goni Gustavo , Smith Ryan H.
Published: November 2020

The nearly four‐decades‐long quasi‐continuous daily measurements of the Florida Current (FC) volume transport with a submarine cable at about 27°N represents the longest climate record of a boundary current in existence. Given the extremely high utility of this time series for monitoring the Atlantic meridional overturning circulation, as well as for improving understanding and prediction of the regional weather, climate phenomena, coastal sea‐level, and ecosystem dynamics, efforts are underway to establish a suitable backup observing system in case the cable becomes inoperable in the future. This study explores the utility of along‐track satellite altimetry measurements since 1993 as a potential cable backup by establishing the relationship between the cross‐stream sea surface height gradients and the FC volume transport derived from cable measurements and ship sections. We find that despite the lower temporal resolution, satellite altimetry can indeed serve as a decent but limited backup observing system. The FC transport inferred from satellite altimetry captures about 60% of the variability observed in the concurrent cable estimates, and the estimated error bars for the altimetry‐derived transport are larger than those of the cable transport (2.1 Sv vs. 1.5 Sv). We nevertheless demonstrate that satellite altimetry reproduces the seasonal, intra‐seasonal, and inter‐annual variability of the FC transport fairly well, as well as large transport anomalies during extreme weather events, such as tropical storms and hurricanes. The altimetry‐derived transport can be provided in near‐real time and serve the need to fill in data gaps in the cable record and assess its quality over time.
Magnetotaxis as an Adaptation to Enable Bacterial Shuttling of Microbial Sulfur and Sulfur Cycling Across Aquatic Oxic‐Anoxic Interfaces
Authors: Li Jinhua , Liu Peiyu , Wang Jian , Roberts Andrew P. , Pan Yongxin
Published: November 2020

Magnetotactic bacteria (MTB) widely inhabit the oxic‐anoxic interface (OAI) of sediments and water columns, with their motility guided by geomagnetic fields (a behavior known as magnetotaxis). Beside biomineralizing membrane‐enveloped magnetite or greigite nanocrystals called magnetosomes, cells of many MTB groups contain numerous sulfur globules within their cells. Here, by combining transmission electron microscopy and synchrotron‐based scanning transmission X‐ray microscopy, we investigated the cellular structure and chemistry of Candidatus Magnetobacterium casensis (Mcas), a giant rod‐shaped MTB from the Nitrospirae phylum. We find that nitrate‐storing vacuoles and linearly polymeric sulfur globules occur exclusively within some Mcas cells along with magnetosomal magnetite. Genomic prediction indicates that Mcas cells have the potential to oxidize sulfide to sulfate (i.e., S2− → S0 → SO32− → SO42−), to reduce sulfate to sulfide (i.e., SO42− → SO32− → S2−), and to reduce nitrate to NH4+/N2. Together with previous environmental observations, comparative genomic analysis allows us to propose a model for Mcas involving the microbial sulfur cycle across aquatic OAIs based on magnetotaxis. Via directional movement guided by geomagnetic fields, Mcas cells shuttle either upward to upper microoxic zones for sulfur oxidation and nitrate accumulation in the OAI, or downward to deeper anoxic zones for sulfur deposition by coupling sulfide oxidation and nitrate reduction. Development of magnetotaxis makes MTB an efficient bacterial shuttle for C, N, S, and Fe across aquatic OAI environments and likely contributes significantly to their global biogeochemical cycling. It also benefits cell growth and magnetosomal magnetite formation in MTB.
Modeling Geomagnetic Interference on Railway Signaling Track Circuits
Authors: Boteler D. H.
Published: November 2020

Misoperation of railway signaling during geomagnetic disturbances has occurred in a number of countries. Railway signals are activated by track circuits that detect the presence of a train in a particular rail section, but geomagnetically induced electric fields can interfere with the track circuit operation, causing the wrong signal to be displayed. This paper develops a new model for track circuit operation that includes the induced geoelectric fields produced by geomagnetic field variations. Rails are modeled as transmission lines with series impedance given by the rail resistance and parallel admittance determined by the current leakage from the rail through the ballast to ground. The transmission line model is then converted into an equivalent‐pi circuit for each rail and these are combined with the track circuit power and relay components to form a nodal admittance network for the track circuit. This is used to examine the effect of induced geoelectric fields on track circuit operation. First, an individual track circuit is examined and it is shown how the length, between insulating rail joints, of the individual rails influences the geomagnetic interference voltage produced across the track circuit relay. Then a series of track circuits is considered: A general solution is developed and then the conditions are identified that allow this to be reduced to a simpler solution considering each track circuit individually. This modeling provides insight into the conditions that produce signaling problems and provides the tools to assess the geomagnetic hazard to railway signaling.
PDK4 promotes vascular calcification by interfering with autophagic activity and metabolic reprogramming
Authors: Ma Wen-Qi , Sun Xue-Jiao , Zhu Yi , Liu Nai-Feng
Published: November 2020

Pyruvate dehydrogenase kinase 4 (PDK4) is an important mitochondrial matrix enzyme in cellular energy regulation. Previous studies suggested that PDK4 is increased in the calcified vessels of patients with atherosclerosis and is closely associated with mitochondrial function, but the precise regulatory mechanisms remain largely unknown. This study aims to investigate the role of PDK4 in vascular calcification and the molecular mechanisms involved. Using a variety of complementary techniques, we found impaired autophagic activity in the process of vascular smooth muscle cells (VSMCs) calcification, whereas knocking down PDK4 had the opposite effect. PDK4 drives the metabolic reprogramming of VSMCs towards a Warburg effect, and the inhibition of PDK4 abrogates VSMCs calcification. Mechanistically, PDK4 disturbs the integrity of the mitochondria-associated endoplasmic reticulum membrane, concomitantly impairing mitochondrial respiratory capacity, which contributes to a decrease in lysosomal degradation by inhibiting the V-ATPase and lactate dehydrogenase B interaction. PDK4 also inhibits the nuclear translocation of the transcription factor EB, thus inhibiting lysosomal function. These changes result in the interruption of autophagic flux, which accelerates calcium deposition in VSMCs. In addition, glycolysis serves as a metabolic adaptation to improve VSMCs oxidative stress resistance, whereas inhibition of glycolysis by 2-deoxy-D-glucose induces the apoptosis of VSMCs and increases the calcium deposition in VSMCs. Our results suggest that PDK4 plays a key role in vascular calcification through autophagy inhibition and metabolic reprogramming.
DEPDC1B is a tumor promotor in development of bladder cancer through targeting SHC1
Authors: Lai Chin-Hui , Xu Kexin , Zhou Jianhua , Wang Mingrui , Zhang Weiyu , Liu Xianhui , Xiong Jie , Wang Tao , Wang Qi , Wang Huanrui , Xu Tao , Hu Hao
Published: November 2020

Bladder cancer is one of the most commonly diagnosed malignant tumors in the urinary system and causes a massive cancer-related death. DEPDC1B is a DEP domain-containing protein that has been found to be associated with a variety of human cancers. This study aimed to explore the role and mechanism of DEPDC1B in the development of bladder cancer. The analysis of clinical specimens revealed the upregulated expression of DEPDC1B in bladder cancer, which was positively related to tumor grade. In vitro and in vivo studies showed that DEPDC1B knockdown could inhibit the growth of bladder cancer cells or xenografts in mice. The suppression of bladder cancer by DEPDC1B was executed through inhibiting cell proliferation, cell migration, and promoting cell apoptosis. Moreover, a mechanistic study found that SHC1 may be an important route through which DEPDC1B regulates the development of bladder cancer. Knockdown of SHC1 in DEPDC1B-overexpressed cancer cells could abolish the promotion effects induced by DEPDC1B. In conclusion, DEPDC1B was identified as a key regulator in the development of bladder cancer, which may be used as a potential therapeutic target in the treatment of bladder cancer.
Uncovering the multifaceted roles played by neutrophils in allogeneic hematopoietic stem cell transplantation
Authors: Tecchio Cristina , Cassatella Marco Antonio
Published: November 2020

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is a life-saving procedure used for the treatment of selected hematological malignancies, inborn errors of metabolism, and bone marrow failures. The role of neutrophils in alloHSCT has been traditionally evaluated only in the context of their ability to act as a first line of defense against infection. However, recent evidence has highlighted neutrophils as key effectors of innate and adaptive immune responses through a wide array of newly discovered functions. Accordingly, neutrophils are emerging as highly versatile cells that are able to acquire different, often opposite, functional capacities depending on the microenvironment and their differentiation status. Herein, we review the current knowledge on the multiple functions that neutrophils exhibit through the different stages of alloHSCT, from the hematopoietic stem cell (HSC) mobilization in the donor to the immunological reconstitution that occurs in the recipient following HSC infusion. We also discuss the influence exerted on neutrophils by the immunosuppressive drugs delivered in the course of alloHSCT as part of graft-versus-host disease (GVHD) prophylaxis. Finally, the potential involvement of neutrophils in alloHSCT-related complications, such as transplant-associated thrombotic microangiopathy (TA-TMA), acute and chronic GVHD, and cytomegalovirus (CMV) reactivation, is also discussed. Based on the data reviewed herein, the role played by neutrophils in alloHSCT is far greater than a simple antimicrobial role. However, much remains to be investigated in terms of the potential functions that neutrophils might exert during a highly complex procedure such as alloHSCT.
Protein identification by 3D OrbiSIMS to facilitate in situ imaging and depth profiling
Authors: Kotowska Anna M. , Trindade Gustavo F. , Mendes Paula M. , Williams Philip M. , Aylott Jonathan W. , Shard Alexander G. , Alexander Morgan R. , Scurr David J.
Published: November 2020

Label-free protein characterization at surfaces is commonly achieved using digestion and/or matrix application prior to mass spectrometry. We report the assignment of undigested proteins at surfaces in situ using secondary ion mass spectrometry (SIMS). Ballistic fragmentation of proteins induced by a gas cluster ion beam (GCIB) leads to peptide cleavage producing fragments for subsequent OrbitrapTM analysis. In this work we annotate 16 example proteins (up to 272 kDa) by de novo peptide sequencing and illustrate the advantages of this approach by characterizing a protein monolayer biochip and the depth distribution of proteins in human skin.
Pathologic and molecular responses to neoadjuvant trastuzumab and/or lapatinib from a phase II randomized trial in HER2-positive breast cancer (TRIO-US B07)
Authors: Hurvitz Sara A. , Caswell-Jin Jennifer L. , McNamara Katherine L. , Zoeller Jason J. , Bean Gregory R. , Dichmann Robert , Perez Alejandra , Patel Ravindranath , Zehngebot Lee , Allen Heather , Bosserman Linda , DiCarlo Brian , Kennedy April , Giuliano Armando , Calfa Carmen , Molthrop David , Mani Aruna , Chen Hsiao-Wang , Dering Judy , Adams Brad , Kotler Eran , Press Michael F. , Brugge Joan S. , Curtis Christina , Slamon Dennis J.
Published: November 2020

In this multicenter, open-label, randomized phase II investigator-sponsored neoadjuvant trial with funding provided by Sanofi and GlaxoSmithKline (TRIO-US B07, Clinical Trials NCT00769470), participants with early-stage HER2-positive breast cancer (N = 128) were recruited from 13 United States oncology centers throughout the Translational Research in Oncology network. Participants were randomized to receive trastuzumab (T; N = 34), lapatinib (L; N = 36), or both (TL; N = 58) as HER2-targeted therapy, with each participant given one cycle of this designated anti-HER2 therapy alone followed by six cycles of standard combination chemotherapy with the same anti-HER2 therapy. The primary objective was to estimate the rate of pathologic complete response (pCR) at the time of surgery in each of the three arms. In the intent-to-treat population, we observed similar pCR rates between T (47%, 95% confidence interval [CI] 30–65%) and TL (52%, 95% CI 38–65%), and a lower pCR rate with L (25%, 95% CI 13–43%). In the T arm, 100% of participants completed all protocol-specified treatment prior to surgery, as compared to 69% in the L arm and 74% in the TL arm. Tumor or tumor bed tissue was collected whenever possible pre-treatment (N = 110), after one cycle of HER2-targeted therapy alone (N = 89), and at time of surgery (N = 59). Higher-level amplification of HER2 and hormone receptor (HR)-negative status were associated with a higher pCR rate. Large shifts in the tumor, immune, and stromal gene expression occurred after one cycle of HER2-targeted therapy. In contrast to pCR rates, the L-containing arms exhibited greater proliferation reduction than T at this timepoint. Immune expression signatures increased in all arms after one cycle of HER2-targeted therapy, decreasing again by the time of surgery. Our results inform approaches to early assessment of sensitivity to anti-HER2 therapy and shed light on the role of the immune microenvironment in response to HER2-targeted agents.
Infection fatality rate of SARS-CoV2 in a super-spreading event in Germany
Authors: Streeck Hendrik , Schulte Bianca , Kümmerer Beate M. , Richter Enrico , Höller Tobias , Fuhrmann Christine , Bartok Eva , Dolscheid-Pommerich Ramona , Berger Moritz , Wessendorf Lukas , Eschbach-Bludau Monika , Kellings Angelika , Schwaiger Astrid , Coenen Martin , Hoffmann Per , Stoffel-Wagner Birgit , Nöthen Markus M. , Eis-Hübinger Anna M. , Exner Martin , Schmithausen Ricarda Maria , Schmid Matthias , Hartmann Gunther
Published: November 2020

A SARS-CoV2 super-spreading event occurred during carnival in a small town in Germany. Due to the rapidly imposed lockdown and its relatively closed community, this town was seen as an ideal model to investigate the infection fatality rate (IFR). Here, a 7-day seroepidemiological observational study was performed to collect information and biomaterials from a random, household-based study population. The number of infections was determined by IgG analyses and PCR testing. We found that of the 919 individuals with evaluable infection status, 15.5% (95% CI:[12.3%; 19.0%]) were infected. This is a fivefold higher rate than the reported cases for this community (3.1%). 22.2% of all infected individuals were asymptomatic. The estimated IFR was 0.36% (95% CI:[0.29%; 0.45%]) for the community and 0.35% [0.28%; 0.45%] when age-standardized to the population of the community. Participation in carnival increased both infection rate (21.3% versus 9.5%, p < 0.001) and number of symptoms (estimated relative mean increase 1.6, p = 0.007). While the infection rate here is not representative for Germany, the IFR is useful to estimate the consequences of the pandemic in places with similar healthcare systems and population characteristics. Whether the super-spreading event not only increases the infection rate but also affects the IFR requires further investigation.
Neuronal processes and glial precursors form a scaffold for wiring the developing mouse cochlea
Authors: Druckenbrod N. R. , Hale E. B. , Olukoya O. O. , Shatzer W. E. , Goodrich L. V.
Published: November 2020

In the developing nervous system, axons navigate through complex terrains that change depending on when and where outgrowth begins. For instance, in the developing cochlea, spiral ganglion neurons extend their peripheral processes through a growing and heterogeneous environment en route to their final targets, the hair cells. Although the basic principles of axon guidance are well established, it remains unclear how axons adjust strategies over time and space. Here, we show that neurons with different positions in the spiral ganglion employ different guidance mechanisms, with evidence for both glia-guided growth and fasciculation along a neuronal scaffold. Processes from neurons in the rear of the ganglion are more directed and grow faster than those from neurons at the border of the ganglion. Further, processes at the wavefront grow more efficiently when in contact with glial precursors growing ahead of them. These findings suggest a tiered mechanism for reliable axon guidance.
Frequency-domain ultrafast passive logic: NOT and XNOR gates
Authors: Maram Reza , Howe James van , Kong Deming , Ros Francesco Da , Guan Pengyu , Galili Michael , Morandotti Roberto , Oxenløwe Leif Katsuo , Azaña José
Published: November 2020

Electronic Boolean logic gates, the foundation of current computation and digital information processing, are reaching final limits in processing power. The primary obstacle is energy consumption which becomes impractically large, > 0.1 fJ/bit per gate, for signal speeds just over several GHz. Unfortunately, current solutions offer either high-speed operation or low-energy consumption. We propose a design for Boolean logic that can achieve both simultaneously (high speed and low consumption), here demonstrated for NOT and XNOR gates. Our method works by passively modifying the phase relationships among the different frequencies of an input data signal to redistribute its energy into the desired logical output pattern. We experimentally demonstrate a passive NOT gate with an energy dissipation of ~1 fJ/bit at 640 Gb/s and use it as a building block for an XNOR gate. This approach is applicable to any system that can propagate coherent waves, such as electromagnetic, acoustic, plasmonic, mechanical, or quantum.
A ribosome-associated chaperone enables substrate triage in a cotranslational protein targeting complex
Authors: Hsieh Hao-Hsuan , Lee Jae Ho , Chandrasekar Sowmya , Shan Shu-ou
Published: November 2020

Protein biogenesis is essential in all cells and initiates when a nascent polypeptide emerges from the ribosome exit tunnel, where multiple ribosome-associated protein biogenesis factors (RPBs) direct nascent proteins to distinct fates. How distinct RPBs spatiotemporally coordinate with one another to affect accurate protein biogenesis is an emerging question. Here, we address this question by studying the role of a cotranslational chaperone, nascent polypeptide-associated complex (NAC), in regulating substrate selection by signal recognition particle (SRP), a universally conserved protein targeting machine. We show that mammalian SRP and SRP receptors (SR) are insufficient to generate the biologically required specificity for protein targeting to the endoplasmic reticulum. NAC co-binds with and remodels the conformational landscape of SRP on the ribosome to regulate its interaction kinetics with SR, thereby reducing the nonspecific targeting of signalless ribosomes and pre-emptive targeting of ribosomes with short nascent chains. Mathematical modeling demonstrates that the NAC-induced regulations of SRP activity are essential for the fidelity of cotranslational protein targeting. Our work establishes a molecular model for how NAC acts as a triage factor to prevent protein mislocalization, and demonstrates how the macromolecular crowding of RPBs at the ribosome exit site enhances the fidelity of substrate selection into individual protein biogenesis pathways.
ST3GAL1 is a target of the SOX2-GLI1 transcriptional complex and promotes melanoma metastasis through AXL
Authors: Pietrobono Silvia , Anichini Giulia , Sala Cesare , Manetti Fabrizio , Almada Luciana L. , Pepe Sara , Carr Ryan M. , Paradise Brooke D. , Sarkaria Jann N. , Davila Jaime I. , Tofani Lorenzo , Battisti Ilaria , Arrigoni Giorgio , Ying Li , Zhang Cheng , Li Hu , Meves Alexander , Fernandez-Zapico Martin E. , Stecca Barbara
Published: November 2020

Understanding the molecular events controlling melanoma progression is of paramount importance for the development of alternative treatment options for this devastating disease. Here we report a mechanism regulated by the oncogenic SOX2-GLI1 transcriptional complex driving melanoma invasion through the induction of the sialyltransferase ST3GAL1. Using in vitro and in vivo studies, we demonstrate that ST3GAL1 drives melanoma metastasis. Silencing of this enzyme suppresses melanoma invasion and significantly reduces the ability of aggressive melanoma cells to enter the blood stream, colonize distal organs, seed and survive in the metastatic environment. Analysis of glycosylated proteins reveals that the receptor tyrosine kinase AXL is a major effector of ST3GAL1 pro-invasive function. ST3GAL1 induces AXL dimerization and activation that, in turn, promotes melanoma invasion. Our data support a key role of the ST3GAL1-AXL axis as driver of melanoma metastasis, and highlight the therapeutic potential of targeting this axis to treat metastatic melanoma.
Pogz deficiency leads to transcription dysregulation and impaired cerebellar activity underlying autism-like behavior in mice
Authors: Suliman-Lavie Reut , Title Ben , Cohen Yahel , Hamada Nanako , Tal Maayan , Tal Nitzan , Monderer-Rothkoff Galya , Gudmundsdottir Bjorg , Gudmundsson Kristbjorn O. , Keller Jonathan R. , Huang Guo-Jen , Nagata Koh-ichi , Yarom Yosef , Shifman Sagiv
Published: November 2020

Several genes implicated in autism spectrum disorder (ASD) are chromatin regulators, including POGZ. The cellular and molecular mechanisms leading to ASD impaired social and cognitive behavior are unclear. Animal models are crucial for studying the effects of mutations on brain function and behavior as well as unveiling the underlying mechanisms. Here, we generate a brain specific conditional knockout mouse model deficient for Pogz, an ASD risk gene. We demonstrate that Pogz deficient mice show microcephaly, growth impairment, increased sociability, learning and motor deficits, mimicking several of the human symptoms. At the molecular level, luciferase reporter assay indicates that POGZ is a negative regulator of transcription. In accordance, in Pogz deficient mice we find a significant upregulation of gene expression, most notably in the cerebellum. Gene set enrichment analysis revealed that the transcriptional changes encompass genes and pathways disrupted in ASD, including neurogenesis and synaptic processes, underlying the observed behavioral phenotype in mice. Physiologically, Pogz deficiency is associated with a reduction in the firing frequency of simple and complex spikes and an increase in amplitude of the inhibitory synaptic input in cerebellar Purkinje cells. Our findings support a mechanism linking heterochromatin dysregulation to cerebellar circuit dysfunction and behavioral abnormalities in ASD.
Two nuclear effectors of the rice blast fungus modulate host immunity via transcriptional reprogramming
Authors: Kim Seongbeom , Kim Chi-Yeol , Park Sook-Young , Kim Ki-Tae , Jeon Jongbum , Chung Hyunjung , Choi Gobong , Kwon Seomun , Choi Jaeyoung , Jeon Junhyun , Jeon Jong-Seong , Khang Chang Hyun , Kang Seogchan , Lee Yong-Hwan
Published: November 2020

Pathogens utilize multiple types of effectors to modulate plant immunity. Although many apoplastic and cytoplasmic effectors have been reported, nuclear effectors have not been well characterized in fungal pathogens. Here, we characterize two nuclear effectors of the rice blast pathogen Magnaporthe oryzae. Both nuclear effectors are secreted via the biotrophic interfacial complex, translocated into the nuclei of initially penetrated and surrounding cells, and reprogram the expression of immunity-associated genes by binding on effector binding elements in rice. Their expression in transgenic rice causes ambivalent immunity: increased susceptibility to M. oryzae and Xanthomonas oryzae pv. oryzae, hemibiotrophic pathogens, but enhanced resistance to Cochliobolus miyabeanus, a necrotrophic pathogen. Our findings help remedy a significant knowledge deficiency in the mechanism of M. oryzae–rice interactions and underscore how effector-mediated manipulation of plant immunity by one pathogen may also affect the disease severity by other pathogens.
Perfect absorption in complex scattering systems with or without hidden symmetries
Authors: Chen Lei , Kottos Tsampikos , Anlage Steven M.
Published: November 2020

Wavefront shaping (WFS) schemes for efficient energy deposition in weakly lossy targets is an ongoing challenge for many classical wave technologies relevant to next-generation telecommunications, long-range wireless power transfer, and electromagnetic warfare. In many circumstances these targets are embedded inside complicated enclosures which lack any type of (geometric or hidden) symmetry, such as complex networks, buildings, or vessels, where the hypersensitive nature of multiple interference paths challenges the viability of WFS protocols. We demonstrate the success of a general WFS scheme, based on coherent perfect absorption (CPA) electromagnetic protocols, by utilizing a network of coupled transmission lines with complex connectivity that enforces the absence of geometric symmetries. Our platform allows for control of the local losses inside the network and of the violation of time-reversal symmetry via a magnetic field; thus establishing CPA beyond its initial concept as the time-reversal of a laser cavity, while offering an opportunity for better insight into CPA formation via the implementation of semiclassical tools.
Consistent population declines but idiosyncratic range shifts in Alpine orchids under global change
Authors: Geppert Costanza , Perazza Giorgio , Wilson Robert J. , Bertolli Alessio , Prosser Filippo , Melchiori Giuseppe , Marini Lorenzo
Published: November 2020

Mountains are plant biodiversity hotspots considered particularly vulnerable to multiple environmental changes. Here, we quantify population changes and range-shift dynamics along elevational gradients over the last three decades for c. two-thirds of the orchid species of the European Alps. Local extinctions were more likely for small populations, after habitat alteration, and predominated at the rear edge of species’ ranges. Except for the most thermophilic species and wetland specialists, population density decreased over time. Declines were more pronounced for rear-edge populations, possibly due to multiple pressures such as climate warming, habitat alteration, and mismatched ecological interactions. Besides these demographic trends, different species exhibited idiosyncratic range shifts with more than 50% of the species lagging behind climate warming. Our study highlights the importance of long-term monitoring of populations and range distributions at fine spatial resolution to be able to fully understand the consequences of global change for orchids.
STAT2 signaling restricts viral dissemination but drives severe pneumonia in SARS-CoV-2 infected hamsters
Authors: Boudewijns Robbert , Thibaut Hendrik Jan , Kaptein Suzanne J. F. , Li Rong , Vergote Valentijn , Seldeslachts Laura , Van Weyenbergh Johan , De Keyzer Carolien , Bervoets Lindsey , Sharma Sapna , Liesenborghs Laurens , Ma Ji , Jansen Sander , Van Looveren Dominique , Vercruysse Thomas , Wang Xinyu , Jochmans Dirk , Martens Erik , Roose Kenny , De Vlieger Dorien , Schepens Bert , Van Buyten Tina , Jacobs Sofie , Liu Yanan , Martí-Carreras Joan , Vanmechelen Bert , Wawina-Bokalanga Tony , Delang Leen , Rocha-Pereira Joana , Coelmont Lotte , Chiu Winston , Leyssen Pieter , Heylen Elisabeth , Schols Dominique , Wang Lanjiao , Close Lila , Matthijnssens Jelle , Van Ranst Marc , Compernolle Veerle , Schramm Georg , Van Laere Koen , Saelens Xavier , Callewaert Nico , Opdenakker Ghislain , Maes Piet , Weynand Birgit , Cawthorne Christopher , Vande Velde Greetje , Wang Zhongde , Neyts Johan , Dallmeier Kai
Published: November 2020

Emergence of SARS-CoV-2 causing COVID-19 has resulted in hundreds of thousands of deaths. In search for key targets of effective therapeutics, robust animal models mimicking COVID-19 in humans are urgently needed. Here, we show that Syrian hamsters, in contrast to mice, are highly permissive to SARS-CoV-2 and develop bronchopneumonia and strong inflammatory responses in the lungs with neutrophil infiltration and edema, further confirmed as consolidations visualized by micro-CT alike in clinical practice. Moreover, we identify an exuberant innate immune response as key player in pathogenesis, in which STAT2 signaling plays a dual role, driving severe lung injury on the one hand, yet restricting systemic virus dissemination on the other. Our results reveal the importance of STAT2-dependent interferon responses in the pathogenesis and virus control during SARS-CoV-2 infection and may help rationalizing new strategies for the treatment of COVID-19 patients.
Proto-oncogene Src links lipogenesis via lipin-1 to breast cancer malignancy
Authors: Song Lintao , Liu Zhihua , Hu Hui-Hui , Yang Ying , Li Terytty Yang , Lin Zhi-Zhong , Ye Jing , Chen Jianing , Huang Xi , Liu Dong-Tai , Zhou Jing , Shi Yiran , Zhao Hao , Xie Changchuan , Chen Lanfen , Song Erwei , Lin Shu-Yong , Lin Sheng-Cai
Published: November 2020

Increased lipogenesis has been linked to an increased cancer risk and poor prognosis; however, the underlying mechanisms remain obscure. Here we show that phosphatidic acid phosphatase (PAP) lipin-1, which generates diglyceride precursors necessary for the synthesis of glycerolipids, interacts with and is a direct substrate of the Src proto-oncogenic tyrosine kinase. Obesity-associated microenvironmental factors and other Src-activating growth factors, including the epidermal growth factor, activate Src and promote Src-mediated lipin-1 phosphorylation on Tyr398, Tyr413 and Tyr795 residues. The tyrosine phosphorylation of lipin-1 markedly increases its PAP activity, accelerating the synthesis of glycerophospholipids and triglyceride. Alteration of the three tyrosine residues to phenylalanine (3YF-lipin-1) disables lipin-1 from mediating Src-enhanced glycerolipid synthesis, cell proliferation and xenograft growth. Re-expression of 3YF-lipin-1 in PyVT;Lpin1−/−mice fails to promote progression and metastasis of mammary tumours. Human breast tumours exhibit increased p-Tyr-lipin-1 levels compared to the adjacent tissues. Importantly, statistical analyses show that levels of p-Tyr-lipin-1 correlate with tumour sizes, lymph node metastasis, time to recurrence and survival of the patients. These results illustrate a direct lipogenesis-promoting role of the pro-oncogenic Src, providing a mechanistic link between obesity-associated mitogenic signaling and breast cancer malignancy.
Alkyl halides as both hydride and alkyl sources in catalytic regioselective reductive olefin hydroalkylation
Authors: Chen Xianxiao , Rao Weidong , Yang Tao , Koh Ming Joo
Published: November 2020

Among the plethora of catalytic methods developed for hydrocarbofunctionalization of olefins to date, reactions that regioselectively install a functionalized alkyl unit at the 2-position of a terminal unactivated C=C bond to afford branched products are scarce. Here, we show that a Ni-based catalyst in conjunction with a stoichiometric reducing agent promote Markovnikov-selective hydroalkylation of unactivated alkenes tethered to a recyclable 8-aminoquinaldine directing auxiliary. These mild reductive processes employ readily available primary and secondary haloalkanes as both the hydride and alkyl donor. Reactions of alkenyl amides with ≥ five-carbon chain length regioselectively afforded β-alkylated products through remote hydroalkylation, underscoring the fidelity of the catalytic process and the directing group’s capability in stabilizing five-membered nickelacycle intermediates. The operationally simple protocol exhibits exceptional functional group tolerance and is amenable to the synthesis of bioactive molecules as well as regioconvergent transformations.
The impact of nitrogen oxides on electrochemical carbon dioxide reduction
Authors: Ko Byung Hee , Hasa Bjorn , Shin Haeun , Jeng Emily , Overa Sean , Chen Wilson , Jiao Feng
Published: November 2020

The electroreduction of carbon dioxide offers a promising avenue to produce valuable fuels and chemicals using greenhouse gas carbon dioxide as the carbon feedstock. Because industrial carbon dioxide point sources often contain numerous contaminants, such as nitrogen oxides, understanding the potential impact of contaminants on carbon dioxide electrolysis is crucial for practical applications. Herein, we investigate the impact of various nitrogen oxides, including nitric oxide, nitrogen dioxide, and nitrous oxide, on carbon dioxide electroreduction on three model electrocatalysts (i.e., copper, silver, and tin). We demonstrate that the presence of nitrogen oxides (up to 0.83%) in the carbon dioxide feed leads to a considerable Faradaic efficiency loss in carbon dioxide electroreduction, which is caused by the preferential electroreduction of nitrogen oxides over carbon dioxide. The primary products of nitrogen oxides electroreduction include nitrous oxide, nitrogen, hydroxylamine, and ammonia. Despite the loss in Faradaic efficiency, the electrocatalysts exhibit similar carbon dioxide reduction performances once a pure carbon dioxide feed is restored, indicating a negligible long-term impact of nitrogen oxides on the catalytic properties of the model catalysts.
Learning by task repetition enhances object individuation and memorization in the elderly
Authors: Tagliabue Chiara F. , Assecondi Sara , Cristoforetti Giulia , Mazza Veronica
Published: November 2020

A decline in visuospatial Working Memory (vWM) is a hallmark of cognitive aging across various tasks, and facing this decline has become the target of several studies. In the current study we tested whether older adults can benefit from task repetition in order to improve their performance in a vWM task. While learning by task repetition has been shown to improve vWM performance in young adulthood, little is known on whether a similar enhancement can be achieved also by the aging population. By combining different behavioral and electrophysiological measures, we investigated whether practicing a specific task (delayed match-to-sample judgement) over four consecutive sessions could improve vWM in healthy aging, and which are the neurophysiological and cognitive mechanisms modulated by learning. Behavioral data revealed that task repetition boosted performance in older participants, both in terms of sensitivity to change (as revealed by d’ measures) as well as capacity estimate (as measured by k values). At the electrophysiological level, results indicated that only after task repetition both target individuation (as evidenced by the N2pc) and vWM maintenance (as reflected by the CDA) were modulated by target numerosity. Our results suggest that repetition learning is effective in enhancing vWM in aging and acts through modifications at different stages of stimulus processing.
p-Phenylenediaminium iodide capping agent enabled self-healing perovskite solar cell
Authors: Zardari Parisa , Rostami Ali , Shekaari Hemayat
Published: November 2020

In this study, p-Phenylenediaminium iodide (PDAI) is used to in-situ growth of 2D (PDA)2PbI4 perovskite layer between (FAPbI3)0.85(MAPbBr3)0.15 3D perovskite and CuSCN as a cheap hole transport layer. The results indicate that the incorporation of 5 mg mL−1 PDAI leads to enlarged grain sizes, compact grain boundaries, reduced trap density, efficient charge extraction, and enhanced stability of perovskite film. Passivation of perovskite film with the appropriate amount of PDAI helps in achieving efficient perovskite solar cell with a PCE as high as 16.10%, a JSC of 21.45 mA cm−2, a VOC of 1.09 V, and FF of 70.21%, with negligible hysteresis and excellent moisture stability which remains 99.01% of its initial PCE value after 5 h in high relative humidity of 90 ± 5% and shows unchanged PCE after 1440 h in low relative humidity of 15 ± 5%. Most strikingly, this ultra-thin 2D passivation layer by the use of PDA cations as a bulky spacer not only passivates the defects on the surface of perovskite film but also induces self-healing properties in PSCs which can be rapidly recovered after keeping away from water vapor exposure. This study introduces the cheap and extra stable perovskite solar cells with outstanding self-healing ability towards commercialization.
Effects of feeding on the physiological performance of the stony coral Pocillopora acuta
Authors: Huang Yan-Leng , Mayfield Anderson B. , Fan Tung-Yung
Published: November 2020

Reef-building corals rely on both heterotrophy and endosymbiotic dinoflagellate autotrophy to meet their metabolic needs. Those looking to culture these organisms for scientific or industrial purposes must therefore consider both feeding regimes and the light environment. Herein the effects of three photosynthetically active radiation (PAR) levels were assessed in fed and unfed specimens of the model coral Pocillopora acuta that were cultured in a recirculating aquaculture system (RAS). Half of the corals were fed Artemia sp. brine shrimp in a separate feeding tank to prevent biofouling, and fragments were exposed to PAR levels of 105, 157, or 250 μmol quanta m−2 s−1 over a 12-h period each day. All cultured corals survived the 140-day treatment, and the physiological response variables assessed-buoyant weight, specific growth rate, linear extension, color, and Fv/Fm-were significantly influenced by feeding, and, to a lesser extent, light. Specifically, fed corals grew faster and larger, and presented darker pigmentation; corals fed at the highest light levels grew at the fastest rate (6 cm year−1 or 175 mg g−1 week−1). Given the high physiological performance observed, we advocate the active feeding of brine shrimp in RAS by those looking to cultivate P. acuta, and likely other corals, over long-term timescales.
Synaptic migration and reorganization after noise exposure suggests regeneration in a mature mammalian cochlea
Authors: Hickman Tyler T. , Hashimoto Ken , Liberman Leslie D. , Liberman M. Charles
Published: November 2020

Overexposure to intense noise can destroy the synapses between auditory nerve fibers and their hair cell targets without destroying the hair cells themselves. In adult mice, this synaptopathy is immediate and largely irreversible, whereas, in guinea pigs, counts of immunostained synaptic puncta can recover with increasing post-exposure survival. Here, we asked whether this recovery simply reflects changes in synaptic immunostaining, or whether there is actual retraction and extension of neurites and/or synaptogenesis. Analysis of the numbers, sizes and spatial distribution of pre- and post-synaptic markers on cochlear inner hair cells, in guinea pigs surviving from 1 day to 6 months after a synaptopathic exposure, shows dramatic synaptic re-organization during the recovery period in which synapse counts recover from 16 to 91% of normal in the most affected regions. Synaptic puncta move all over the hair cell membrane during recovery, translocating far from their normal positions at the basolateral pole, and auditory-nerve terminals extend towards the hair cell’s apical end to re-establish contact with them. These observations provide stronger evidence for spontaneous neural regeneration in a mature mammalian cochlea than can be inferred from synaptic counts alone.
Author Correction: Enhancing doping contrast and optimising quantification in the scanning electron microscope by surface treatment and Fermi level pinning
Authors: Chee Augustus K. W.
Published: November 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
An insight into the electro-chemical properties of halogen (F, Cl and Br) doped BP and BN nanocages as anodes in metal-ion batteries
Authors: Abedi Maryam , Eslami Mohammad , Ghadiri Mahdi , Mohammadinia Samira
Published: November 2020

Here, electro-chemical properties of BN and BP nanocages as anodes in metal-ion batteries are examined. The effect of halogens adoption of BN and BP-NCs on electro-chemical properties of M-IBs are investigated. Results showed that the BP nanocages as anode electrode in M-IBs has higher efficiency than BN nanocages and the K-IB has higher cell voltage than N-IBs. Results indicated that the halogens adoption of BN and BP-NCs are improved the cell voltage of M-IBs. Results proved that the F-doped M-IBs have higher cell voltage than M-IBs. Finally, F-B17P18 as anodes in K-IB is proposed as suitable electrodes.
The use of prostate specific antigen density to predict clinically significant prostate cancer
Authors: Yusim Igor , Krenawi Muhammad , Mazor Elad , Novack Victor , Mabjeesh Nicola J.
Published: November 2020

The purpose of this study was to assess the predictive value of prostate specific antigen density (PSAD) for detection of clinically significant prostate cancer in men undergoing systematic transrectal ultrasound (TRUS)-guided prostate biopsy. We retrospectively analyzed data of men who underwent TRUS-guided prostate biopsy because of elevated PSA (≤ 20 ng/ml) or abnormal digital rectal examination. Receiver operating characteristic curve analysis to compare PSA and PSAD performance and chi-square automatic interaction detector methodologies were used to identify predictors of clinically significant cancer (Gleason score ≥ 7 or international society of urological pathology grade group ≥ 2). Nine-hundred and ninety-two consecutive men with a median age of 66 years (IQR 61–71) were included in the study. Median PSAD was 0.10 ng/ml2 (IQR 0.10–0.22). Prostate adenocarcinoma was diagnosed in 338 men (34%). Clinically significant prostate adenocarcinoma was diagnosed in 167 patients (50% of all cancers and 17% of the whole cohort). The AUC to predict clinically significant prostate cancer was 0.64 for PSA and 0.78 for PSAD (P < 0.001). The highest Youden's index for PSAD was at 0.20 ng/ml2 with 70% sensitivity and 79% specificity for the diagnosis of clinically significant cancer. Men with PSAD < 0.09 ng/ml2 had only 4% chance of having clinically significant disease. The detection rate of clinically significant prostate cancer in patients with PSAD between 0.09 and 0.19 ng/ml2 was significantly higher when prostate volume was less than 33 ml. In conclusion, PSAD was a better predictor than PSA alone of clinically significant prostate cancer in patients undergoing TRUS-guided biopsy. Patients with PSAD below 0.09 ng/ml2 were unlikely to harbor clinically significant prostate cancer. Combining PSAD in the gray zone (0.09–0.19) with prostate volume below 33 ml adds diagnostic value of clinically significant prostate cancer.
Impairment of microbial and meiofaunal ecosystem functions linked to algal forest loss
Authors: Bianchelli Silvia , Danovaro Roberto
Published: November 2020

Habitat loss is jeopardizing marine biodiversity. In the Mediterranean Sea, the algal forests of Cystoseira spp. form one of the most complex, productive and vulnerable shallow-water habitats. These forests are rapidly regressing with negative impact on the associated biodiversity, and potential consequences in terms of ecosystem functioning. Here, by comparing healthy Cystoseira forests and barren grounds (i.e., habitats where the macroalgal forests disappeared), we assessed the effects of habitat loss on meiofaunal and nematode biodiversity, and on some ecosystem functions (here measured in terms of prokaryotic and meiofaunal biomass). Overall, our results suggest that the loss of Cystoseira forests and the consequent barren formation is associated with the loss of meiofaunal higher taxa and a decrease of nematode biodiversity, leading to the collapse of the microbial and meiofaunal variables of ecosystem functions. We conclude that, given the very limited resilience of these ecosystems, active restoration of these vulnerable habitats is needed, in order to recover their biodiversity, ecosystem functions and associated services.
The effects of acute aerobic exercise on inhibitory control and resting state heart rate variability in children with ADHD
Authors: Yu Chien-Lin , Hsieh Shu-Shih , Chueh Ting-Yu , Huang Chung-Ju , Hillman Charles H. , Hung Tsung-Min
Published: November 2020

The current study examined the effects of acute moderate-intensity aerobic exercise (MAE) on inhibitory control and resting-state heart rate variability (HRV) in children with Attention-Deficit/Hyperactivity Disorder (ADHD). Our data show that acute MAE resulted in higher response accuracy of a modified flanker task regardless of task difficulty for 60 min (p = .001). Aerobic exercise further resulted in more effective conflict detection, as measured by greater amplitude (p = .012) and shorter latency (p = .029) of the N2 component of event-related brain potential, for 60 min regardless of task difficulty. In contrast, acute MAE did not modulate sympathovagal balance signified by HRV at either 30 min or 60 min following exercise cessation. Collectively, our findings suggest that the beneficial effects of acute aerobic exercise on inhibitory control are sustained for 60 min in children with ADHD. However, acute aerobic exercise may not modulate sympathovagal balance during the post-exercise recovery. Overall, we highlight the importance of acute aerobic exercise for children with ADHD as a potential means to facilitate brain health.