bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Shipwreck of the Airship “Dirigibile Italia” in the 1928 Polar Venture: A Retrospective Analysis of the Ionospheric and Geomagnetic Conditions
Authors: Zolesi B. , Pezzopane M. , Bianchi C. , Meloni A. , Cander Lj. R. , Tozzi R. 
Published: June 2020

AbstractOn 25 May 1928 the airship “Dirigibile Italia” during its return trip to the base in NyAlesund, after overflying the North Pole, shipwrecked on the ice‐pack in a region at about 400 km northeast of Svalbard Islands. Survivors, by using a portable high frequency (HF) radio transmitter, tried unsuccessfully to send SOS messages and to establish a radio link with the ship “Città di Milano” of the Italian Navy, closely anchored at King's Bay. Only after 9 days of repeated radio‐distress transmissions, a Russian radio amateur close to the town of Arkhangelsk about 1,900 km away was able to receive the messages launched by the survivors and raise the alarm. This paper aims at giving a retrospective analysis of the ionospheric and geomagnetic conditions of that epoch in order to explain the HF radio communications problems encountered by the survivors. The International Reference Ionosphere model has been applied, and early geomagnetic measurements have been evaluated, to come up with theories explaining the events. We assert the HF transmission difficulties were associated with the “radio silent” or “dead zones” associated with F‐region propagation. These may have been exacerbated by solar and geomagnetically disturbed conditions of the days immediately following the airship wreck.
High‐Speed Solar Wind Imprints on the Ionosphere During the Recovery Phase of the August 2018 Geomagnetic Storm
Authors: Ren Dexin , Lei Jiuhou , Zhou Su , Li Wenbo , Huang Fuqing , Luan Xiaoli , Dang Tong , Liu Yu 
Published: June 2020

AbstractThe low‐latitude ionospheric TEC observed by the Beidou geostationary satellite showed large enhancement during 27–30 August 2018 of the storm recovery phase. The cause of the positive ionospheric storm during the recovery phase has yet to be resolved. In this study, multiple observations, including aurora, high‐latitude convection, potential, and the TEC maps, were used to study the contributions from the high‐speed solar wind to the ionosphere during the recovery phase of the storm. It was found that the high‐speed solar wind was effective in modulating the intensity and the size of the auroral oval, high‐latitude convection, and potential pattern. The Thermosphere Ionosphere Electrodynamics General Circulation Model generally reproduced the observed evolution of the ionosphere at high latitudes during the recovery phase of the storm, and it was used to quantitatively investigate the effects of the high‐speed solar wind on the recovery phase ionosphere. The results suggested that the high‐speed solar wind caused increase of TEC at auroral oval was about 2 TECU. The high‐speed solar wind, combined with oscillating interplanetary magnetic field Bz, led to the enhancement of the low‐latitude prompt penetrating electric fields and increased the low‐latitude TEC of about 2 TECU. Therefore, the high‐speed solar wind was a possible driver to the ionospheric positive storm during the recovery phase, but the causes for the more than 10‐TECU enhancement at low and middle latitudes during the recovery phase of this event are unknown.
Flow Recession Equations for Karst Systems
Authors: Basha H. A. 
Published: June 2020

AbstractThe proper management and exploitation of karst water resources require first and foremost an accurate characterization of the karst aquifer. Analysis of the recession curve of a spring hydrograph is one efficient approach of determining the hydraulic characteristics of a karst system. In the present work, six flow recession equations for various flow conditions are presented that highlight the dichotomy of the dual flow characteristics between the fissured matrix and the conduit system. They are defined in terms of lumped physical parameters that characterize the dominant flow processes occurring in a karst aquifer. The processes consist either of a pressure‐driven flow or a gravity‐driven flow in a conduit that is interacting laterally with the groundwater flow in the surrounding matrix. The recession equations are composed of two distinct functions that represent separately the flood flow component and the base flow component. They allow the separate evaluation of the conduit and matrix drainage processes and capture the strongly varying recession in the early stages as well as the slow decline in the latter stages of the spring recession hydrograph. Approximate equations for large times are also developed that allow the direct estimation of the model parameters of the karst system using simple algebraic formulas. The flow recession equations were applied to three real karst systems and proved to be effective in simulating the observed recession hydrographs and estimating its hydraulic properties.
Changes in the transcriptome, ploidy, and optimal light intensity of a cryptomonad upon integration into a kleptoplastic dinoflagellate
Authors: Onuma Ryo , Hirooka Shunsuke , Kanesaki Yu , Fujiwara Takayuki , Yoshikawa Hirofumi , Miyagishima Shin-ya 
Published: June 2020

AbstractEndosymbiosis of unicellular eukaryotic algae into previously nonphotosynthetic eukaryotes has established chloroplasts in several eukaryotic lineages. In addition, certain unicellular organisms in several different lineages ingest algae and utilize them as temporal chloroplasts (kleptoplasts) for weeks to months before digesting them. Among these organisms, the dinoflagellate Nusuttodinium aeruginosum ingests the cryptomonad Chroomonas sp. and enlarges the kleptoplast with the aid of the cryptomonad nucleus. To understand how the cryptomonad nucleus is remodeled in the dinoflagellate, here we examined changes in the transcriptome and ploidy of the ingested nucleus. We show that, after ingestion, genes involved in metabolism, translation, and DNA replication are upregulated while those involved in sensory systems and cell motility are downregulated. In the dinoflagellate cell, the cryptomonad nucleus undergoes polyploidization that correlates with an increase in the mRNA levels of upregulated genes. In addition, the ingested nucleus almost loses transcriptional responses to light. Because polyploidization and loss of transcriptional regulation are also known to have occurred during the establishment of endosymbiotic organelles, these changes are probably a common trend in endosymbiotic evolution. Furthermore, we show that the kleptoplast and dinoflagellate are more susceptible to high light than the free-living cryptomonad but that the ingested nucleus reduces this damage.
The role of social cognition skills and social determinants of health in predicting symptoms of mental illness
Authors: Santamaría-García Hernando , Baez Sandra , Gómez Carlos , Rodríguez-Villagra Odir , Huepe David , Portela Maria , Reyes Pablo , Klahr Joel , Matallana Diana , Ibanez Agustin 
Published: June 2020

AbstractSocial factors, such as social cognition skills (SCS) and social determinants of health (SDH), may be vital for mental health, even when compared with classical psycho-physical predictors (demographic, physical, psychiatric, and cognitive factors). Although major risk factors for psychiatric disorders have been previously assessed, the relative weight of SCS and SDH in relation to classical psycho-physical predictors in predicting symptoms of mental disorders remains largely unknown. In this study, we implemented multiple structural equation models (SEM) from a randomized sample assessed in the Colombian National Mental Health Survey of 2015 (CNMHS,n = 2947, females: 1348) to evaluate the role of SCS, SDH, and psycho-physical factors (totaling 17 variables) as predictors of mental illness symptoms (anxiety, depression, and other psychiatric symptoms). Specifically, we assessed the structural equation modeling of (a) SCS (emotion recognition and empathy skills); (b) SDH (including the experience of social adversities and social protective factors); (c) and classical psycho-physical factors, including psychiatric antecedents, physical–somatic factors (chronic diseases), and cognitive factors (executive functioning). Results revealed that the emotion recognition skills, social adverse factors, antecedents of psychiatric disorders and chronic diseases, and cognitive functioning were the best predictors of symptoms of mental illness. Moreover, SCS, particularly emotion recognition skills, and SDH (experiences of social adversities, familial, and social support networks) reached higher predictive values of symptoms than classical psycho-physical factors. Our study provides unprecedented evidence on the impact of social factors in predicting symptoms of mental illness and highlights the relevance of these factors to track early states of disease.
The inhibition of IL-2/IL-2R gives rise to CD8+ T cell and lymphocyte decrease through JAK1-STAT5 in critical patients with COVID-19 pneumonia
Authors: Shi Hongbo , Wang Wenjing , Yin Jiming , Ouyang Yabo , Pang Lijun , Feng Yingmei , Qiao Luxin , Guo Xianghua , Shi Honglin , Jin Ronghua , Chen Dexi 
Published: June 2020

AbstractAlthough most patients with COVID-19 pneumonia have a good prognosis, some patients develop to severe or critical illness, and the mortality of critical cases is up to 61.5%. However, specific molecular information about immune response in critical patients with COVID-19 is poorly understood. A total of 54 patients were enrolled and divided into three groups, among which 34 were common, 14 were severe, and 6 were critical. The constitution of peripheral blood mononuclear cells (PBMC) in patients was analyzed by CyTOF. The profile of cytokines was examined in plasma of patients using luminex. The IL-2 signaling pathway was investigated in the PBMC of patients by qRT-PCR. The count and percentage of lymphocytes were significantly decreased in critical patients compared to common and severe patients with COVID-19 pneumonia. The count of T cells, B cells, and NK cells was remarkably decreased in critical patients compared to normal controls. The percentage of CD8+ T cells was significantly lower in critical patients than that in common and severe patients with COVID-19 pneumonia. The expression of IL-2R, JAK1, and STAT5 decreased in PBMC of common, severe, and critical patients, but IL-2 level was elevated in severe patients and decreased in critical patients with COVID-19 pneumonia. The decrease of CD8+ T cells in critical patients with COVID-19 pneumonia may be related to the IL-2 signaling pathway. The inhibition of IL-2/IL-2R gives rise to CD8+ T cell and lymphocyte decrease through JAK1-STAT5 in critical patients with COVID-19 pneumonia.
Human telomerase reverse transcriptase positively regulates mitophagy by inhibiting the processing and cytoplasmic release of mitochondrial PINK1
Authors: Shin Woo Hyun , Chung Kwang Chul 
Published: June 2020

AbstractMutations in the phosphatase and tensin homologue-induced putative kinase 1 (PINK1) gene have been linked to an early-onset autosomal recessive form of familial Parkinson′s disease (PD). PINK1, a mitochondrial serine/threonine-protein kinase, plays an important role in clearing defective mitochondria by mitophagy – the selective removal of mitochondria through autophagy. Evidence suggests that alteration of the PINK1 pathway contributes to the pathogenesis of PD, but the mechanisms by which the PINK1 pathway regulates mitochondrial quality control through mitophagy remain unclear. Human telomerase reverse transcriptase (hTERT) is a catalytic subunit of telomerase that functions in telomere maintenance as well as several non-telomeric activities. For example, hTERT has been associated with cellular immortalization, cell growth control, and mitochondrial regulation. We determined that hTERT negatively regulates the cleavage and cytosolic processing of PINK1 and enhances its mitochondrial localization by inhibiting mitochondrial processing peptidase β (MPPβ). Consequently, hTERT promotes mitophagy following carbonyl cyanide m-chlorophenylhydrazone (CCCP)-induced mitochondrial dysfunction and improves the function of damaged mitochondria by modulating PINK1. These findings suggest that hTERT positively regulates PINK1 function, leading to increased mitophagy following mitochondrial damage.
Structure and mechanism of the Nap adhesion complex from the human pathogen Mycoplasma genitalium
Authors: Aparicio David , Scheffer Margot P. , Marcos-Silva Marina , Vizarraga David , Sprankel Lasse , Ratera Mercè , Weber Miriam S. , Seybert Anja , Torres-Puig Sergi , Gonzalez-Gonzalez Luis , Reitz Julian , Querol Enrique , Piñol Jaume , Pich Oscar Q. , Fita Ignacio , Frangakis Achilleas S. 
Published: June 2020

AbstractMycoplasma genitalium is a human pathogen adhering to host target epithelial cells and causing urethritis, cervicitis and pelvic inflammatory disease. Essential for infectivity is a transmembrane adhesion complex called Nap comprising proteins P110 and P140. Here we report the crystal structure of P140 both alone and in complex with the N-terminal domain of P110. By cryo-electron microscopy (cryo-EM) and tomography (cryo-ET) we find closed and open Nap conformations, determined at 9.8 and 15 Å, respectively. Both crystal structures and the cryo-EM structure are found in a closed conformation, where the sialic acid binding site in P110 is occluded. By contrast, the cryo-ET structure shows an open conformation, where the binding site is accessible. Structural information, in combination with functional studies, suggests a mechanism for attachment and release of M. genitalium to and from the host cell receptor, in which Nap conformations alternate to sustain motility and guarantee infectivity.
High-resolution patterning of colloidal quantum dots via non-destructive, light-driven ligand crosslinking
Authors: Yang Jeehye , Hahm Donghyo , Kim Kyunghwan , Rhee Seunghyun , Lee Myeongjae , Kim Seunghan , Chang Jun Hyuk , Park Hye Won , Lim Jaehoon , Lee Minkyoung , Kim Hyeokjun , Bang Joohee , Ahn Hyungju , Cho Jeong Ho , Kwak Jeonghun , Kim BongSoo , Lee Changhee , Bae Wan Ki , Kang Moon Sung 
Published: June 2020

AbstractEstablishing multi-colour patterning technology for colloidal quantum dots is critical for realising high-resolution displays based on the material. Here, we report a solution-based processing method to form patterns of quantum dots using a light-driven ligand crosslinker, ethane-1,2-diyl bis(4-azido-2,3,5,6-tetrafluorobenzoate). The crosslinker with two azide end groups can interlock the ligands of neighbouring quantum dots upon exposure to UV, yielding chemically robust quantum dot films. Exploiting the light-driven crosslinking process, different colour CdSe-based core-shell quantum dots can be photo-patterned; quantum dot patterns of red, green and blue primary colours with a sub-pixel size of 4 μm × 16 μm, corresponding to a resolution of >1400 pixels per inch, are demonstrated. The process is non-destructive, such that photoluminescence and electroluminescence characteristics of quantum dot films are preserved after crosslinking. We demonstrate that red crosslinked quantum dot light-emitting diodes exhibiting an external quantum efficiency as high as 14.6% can be obtained.
Impacts drive lunar rockfalls over billions of years
Authors: Bickel Valentin Tertius , Aaron Jordan , Manconi Andrea , Loew Simon , Mall Urs 
Published: June 2020

AbstractPast exploration missions have revealed that the lunar topography is eroded through mass wasting processes such as rockfalls and other types of landslides, similar to Earth. We have analyzed an archive of more than 2 million high-resolution images using an AI and big data-driven approach and created the first global map of 136.610 lunar rockfall events. Using this map, we show that mass wasting is primarily driven by impacts and impact-induced fracture networks. We further identify a large number of currently unknown rockfall clusters, potentially revealing regions of recent seismic activity. Our observations show that the oldest, pre-Nectarian topography still hosts rockfalls, indicating that its erosion has been active throughout the late Copernican age and likely continues today. Our findings have important implications for the estimation of the Moon’s erosional state and other airless bodies as well as for the understanding of the topographic evolution of planetary surfaces in general.
A bedform phase diagram for dense granular currents
Authors: Smith Gregory , Rowley Peter , Williams Rebecca , Giordano Guido , Trolese Matteo , Silleni Aurora , Parsons Daniel R. , Capon Samuel 
Published: June 2020

AbstractPyroclastic density currents (PDCs) are a life-threatening volcanic hazard. Our understanding and hazard assessments of these flows rely on interpretations of their deposits. The occurrence of stratified layers, cross-stratification, and bedforms in these deposits has been assumed as indicative of dilute, turbulent, supercritical flows causing traction-dominated deposition. Here we show, through analogue experiments, that a variety of bedforms can be produced by denser, aerated, granular currents, including backset bedforms that are formed in waning flows by an upstream-propagating granular bore. We are able to, for the first time, define phase fields for the formation of bedforms in PDC deposits. We examine how our findings impact the understanding of bedform features in outcrop, using the example of the Pozzolane Rosse ignimbrite of the Colli Albani volcano, Italy, and thus highlight that interpretations of the formative mechanisms of these features observed in the field must be reconsidered.
Mechanism of effector capture and delivery by the type IV secretion system from Legionella pneumophila
Authors: Meir Amit , Macé Kevin , Lukoyanova Natalya , Chetrit David , Hospenthal Manuela K. , Redzej Adam , Roy Craig , Waksman Gabriel 
Published: June 2020

AbstractLegionella pneumophila is a bacterial pathogen that utilises a Type IV secretion (T4S) system to inject effector proteins into human macrophages. Essential to the recruitment and delivery of effectors to the T4S machinery is the membrane-embedded T4 coupling complex (T4CC). Here, we purify an intact T4CC from the Legionella membrane. It contains the DotL ATPase, the DotM and DotN proteins, the chaperone module IcmSW, and two previously uncharacterised proteins, DotY and DotZ. The atomic resolution structure reveals a DotLMNYZ hetero-pentameric core from which the flexible IcmSW module protrudes. Six of these hetero-pentameric complexes may assemble into a 1.6-MDa hexameric nanomachine, forming an inner membrane channel for effectors to pass through. Analysis of multiple cryo EM maps, further modelling and mutagenesis provide working models for the mechanism for binding and delivery of two essential classes of Legionella effectors, depending on IcmSW or DotM, respectively.
Thermal energy storage and thermal conductivity properties of Octadecanol-MWCNT composite PCMs as promising organic heat storage materials
Authors: Al-Ahmed Amir , Sarı Ahmet , Mazumder Mohammad Abu Jafar , Hekimoğlu Gökhan , Al-Sulaiman Fahad A. , Inamuddin  
Published: June 2020

AbstractFatty alcohols have been identified as promising organic phase change materials (PCMs) for thermal energy storage, because of their suitable temperature range, nontoxicity and can be obtained from both natural and synthetic sources. Like all other organic PCMs, octadecanol (OD) as PCM suffers from low thermal conductivity (TC). In this work, to enhance its TC, it was grafted on the functionalized MWCNT and were used as a conductive filler to enhance overall thermal properties of OD in a composite PCM (CPCMs) structure. The OD/OD-g-MWCNT sample showed better dispersion within the composites and the presence of additional OD boosted the overall heat storage enthalpy compared to that of plane composite sample with OD/MWCNT. In a non-quantitative approach, it was observed that, any increase in grafting ratio of OD increases the heat storage enthalpy of the composites. The heat storage enthalpy of (267.7 J/g) OD/OD-g-MWCNT(4:1)-5wt% composite PCM had reached very close to the heat storage enthalpy value of pure OD (269.3 J/g), and much higher than that of OD/MWCNT-5wt% (234.5 J/g). Champion sample i.e. OD/OD-g-MWCNT (4:1)-5wt%, showed good heat storage enthalpy, cycling performance, thermal stability and TC enhancement by 262.5%.
Life Cycle Assessment of Compostable Coffee Pods: A US University Based Case Study
Authors: Kooduvalli Komal , Vaidya Uday Kumar , Ozcan Soydan 
Published: June 2020

AbstractSingle-serve machines have proven to be a rapid and convenient mechanism for preparing coffee for consumption. However, disposing the single-use coffee pods accompanying each use creates insurmountable waste in landfills. With the introduction of biobased products being certified as industrially compostable, there is scope for an effective waste stream for nearly all biobased products that avoids adding to landfills. The case presented in this paper demonstrates the success of composting compostable coffee pods within a local industrial-scale composting facility. Utilizing the existing local composting facility at the University of Tennessee–Knoxville, a life cycle assessment was performed to calculate the overall embodied energy and related environmental impact(s) to determine the feasibility of using compostable coffee pods over conventional plastic ones. Testing showed complete degradation within 46 days, proving composting to be a feasible waste stream option and a sustainable marketing edge while treading the path toward a circular economy. Cost savings of 21% were realized in terms of waste disposal, in addition to creating a value-added product at the end of the coffee pods life cycle, with nutrient-rich compost being recirculated to campus gardens and farms.
Measurement of excitation-inhibition ratio in autism spectrum disorder using critical brain dynamics
Authors: Bruining Hilgo , Hardstone Richard , Juarez-Martinez Erika L. , Sprengers Jan , Avramiea Arthur-Ervin , Simpraga Sonja , Houtman Simon J. , Poil Simon-Shlomo , Dallares Eva , Palva Satu , Oranje Bob , Matias Palva J. , Mansvelder Huibert D. , Linkenkaer-Hansen Klaus 
Published: June 2020

AbstractBalance between excitation (E) and inhibition (I) is a key principle for neuronal network organization and information processing. Consistent with this notion, excitation-inhibition imbalances are considered a pathophysiological mechanism in many brain disorders including autism spectrum disorder (ASD). However, methods to measure E/I ratios in human brain networks are lacking. Here, we present a method to quantify a functional E/I ratio (fE/I) from neuronal oscillations, and validate it in healthy subjects and children with ASD. We define structural E/I ratio in an in silico neuronal network, investigate how it relates to power and long-range temporal correlations (LRTC) of the network’s activity, and use these relationships to design the fE/I algorithm. Application of this algorithm to the EEGs of healthy adults showed that fE/I is balanced at the population level and is decreased through GABAergic enforcement. In children with ASD, we observed larger fE/I variability and stronger LRTC compared to typically developing children (TDC). Interestingly, visual grading for EEG abnormalities that are thought to reflect E/I imbalances revealed elevated fE/I and LRTC in ASD children with normal EEG compared to TDC or ASD with abnormal EEG. We speculate that our approach will help understand physiological heterogeneity also in other brain disorders.