bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved STEM/EDX Quantitative Method for Dopant Profiling at the Nanoscale
Authors: Makarem Raghda , Cristiano Filadelfo , Muller Dominique , Fazzini Pier Francesco
Published: January 2020

In this paper, an improved quantification technique for STEM/EDX measurements of 1D dopant profiles based on the Cliff-Lorimer equation is presented. The technique uses an iterative absorption correction procedure based on density models correlating the local mass density and composition of the specimen. Moreover, a calibration and error estimation procedure based on linear regression and error propagation is proposed in order to estimate the total measurement error in the dopant density. The proposed approach is applied to the measurement of the As profile in a nanodevice test structure. For the calibration, two crystalline Si specimens implanted with different As doses have been used, and the calibration of the Cliff-Lorimer coefficients has been carried out using Rutherford Back Scattering measurements. The As profile measurement has been carried out on an FinFET test structure, showing that quantitative results can be obtained in the nanometer scale and for dopant atomic densities lower than 1%. Using the proposed approach, the measurement error and detection limit for our experimental setup are calculated and the possibility to improve this limit by increasing the observation time is discussed.
Instruments for pain assessment in patients with advanced dementia: A systematic review of the evidence for Latin America
Authors: Coca Silvia Mercedes , Abeldaño Zuñiga Roberto Ariel
Published: January 2020

Objective

Pain treatment is an essential component of care for elderly patients with advanced dementia. The objective of this study was to identify and analyze the different scales used for pain assessment in elderly persons diagnosed with dementia, in the literature available at the Latin American level.

Method

A systematic review was performed on the existing scales for pain assessment in elderly people diagnosed with Alzheimer's disease, vascular dementia, and dementia with Lewy bodies.

Results

226 articles were retrieved from the PUBMED, BIREME, and Scielo databases, of which a total of 10 articles entered the systematic review. The instruments identified in these publications were PAINAD, Abbey, McGill, and PACSLAC, while the Colored Pain Scale, Faces Pain Scale, and VAS scales were used as the silver standard. In Spanish, the Abbey scale, and in Portuguese, the PACSLAC scale showed the best reliability and validity coefficients.

Significance of results

It is concluded that there are only two appropriate scales for the assessment of pain in people with dementia in the region of interest of this study. It is recommended to generate more evidence for a more accurate assessment of pain in people with dementia.
Plasminogen activator inhibitor-1 (PAI-1) 4G/5G promoter	polymorphisms and risk of venous thromboembolism – a meta-analysis and	systematic review
Authors: Zhang Qiang , Jin YunRui , Li XueMei , Peng XingQiao , Peng Na , Song JiFang , Xu Mingfang
Published: January 2020

Summary: Background: A 4G/5G polymorphism in the promoter region of the plasminogen activator inhibitor type 1 (PAI-1) gene has been reported to enhance the plasma levels of PAI-1, which plays an important role in fibrinolysis disorders and venous thromboembolism, but a large number of studies have reported inconclusive results. Therefore, we performed a meta-analysis to analysis these associations. Materials and methods: We performed a publication search for articles published before April 2019 by using the electronic databases of web of Science, Embase, PubMed, CNKI, CBM and WanFang data with the following terms “PAI-1”, “polymorphism”, “Venous Thromboembolism”. Two investigators independently extracted data and assessed study quality. Statistical analyses were undertaken using Stata 14.0. Results: A total of 27 studies, with 3135 patients and 5346 controls were included. Overall, the variant PAI-1 4G/4G and PAI-1 4G/5G was associated with venous thromboembolism risk, compared with the PAI-1 5G/5G allele in the populations included in the analysis. Stratified analysis revealed that PAI-1 4G/4G and PAI-1 4G/5G genotypes were associated with an increased VTE risk among Asia populations in all five genetic models. Conclusions: The PAI-1 4G/5G polymorphism may be a potential biomarker of VTE risk, particularly in Asia populations. Further larger studies with multi-ethnic populations are required to further assess the association between PAI-1 4G/4G polymorphisms and VTE risk.
Effekt Glückssache?
Authors: Dickhäuser Oliver , Heinze Adrian , Hamm Marie Luisa , Bales Anika Sophie , Bellmann Svenja Amelie , Böger Daniela , Gagelmann Lidia Katarzyna , Kuhlenkamp Felix , Merger Julia Kathleen , Viehweger Hanna , Ziegler Julian , Neuenstein Anna von
Published: January 2020

Zusammenfassung. Damisch, Stoberock und Mussweiler (2010) zeigten in einer Reihe von Experimenten, dass die Induktion von abergläubigen Glücksüberzeugungen im Vergleich zu einer Kontrollgruppe zu einer besseren Leistung in unterschiedlichen kognitiven und motorischen Aufgaben führt. Wir führten zwei konzeptuelle Replikationen ( N Studie 1 = 101, N Studie 2 = 175) eines der Experimente durch, in denen wir untersuchten, ob Versuchspersonen in einer Online-Studie durch die Induktion Glück zu haben, bessere Leistungen beim Lösen von Anagrammaufgaben zeigten als die Kontrollgruppe und untersuchten dabei in Studie 2 mit einem anderen Manipulationsstimulus zusätzlich den Effekt von Pechinduktion auf die Leistung. Des Weiteren wurde in beiden Studien der Effekt der Induktion auf die Selbstwirksamkeitserwartung untersucht. Den Hypothesen widersprechend zeigte sich kein statistisch signifikanter Effekt der Glücks- bzw. Pechinduktion auf die Leistung. Auf die Selbstwirksamkeitserwartung zeigte sich nur in Studie 2 ein kleiner Effekt. Zu geringe Teststärke und nicht erfolgreiche Manipulation können in beiden Studien als Ursache für die erfolglose Replikation ausgeschlossen werden. Wir diskutieren, dass Effekte von Glücks-Induktionen auf Leistung offensichtlich nur unter sehr spezifischen, oft nicht replizierbaren Randbedingungen gezeigt werden können.
Self-assembly and hydrogel formation ability of Fmoc-dipeptides comprising α-methyl-L-phenylalanine
Authors: Arakawa Hanae , Takeda Kumi , Higashi Sayuri L. , Shibata Aya , Kitamura Yoshiaki , Ikeda Masato
Published: January 2020

Various biofunctional hydrogel materials can be fabricated in aqueous media through the self-assembly of peptide derivatives, forming supramolecular nanostructures and their three-dimensional networks. In this study, we describe the self-assembly of new Fmoc-dipeptides comprising α-methyl-L-phenylalanine. We found that the position and number of methyl groups introduced onto the α carbons of the Fmoc-dipeptides by α-methyl-L-phenylalanine have a marked influence on the morphology of the supramolecular nanostructure as well as the hydrogel (network) formation ability.
Nutrition care for chronic kidney disease during pregnancy: an updated review
Authors: Reyes-López María Angélica , Piccoli Giorgina B , Leone Filomena , Orozco-Guillén Alejandra , Perichart-Perera Otilia
Published: January 2020

Cases of chronic kidney disease (CKD), including CKD in pregnant women, have increased globally in recent years. CKD during pregnancy is associated with a higher risk of adverse outcomes, including gestational hypertension, preeclampsia, intrauterine growth restriction, and preterm birth, among others. Nutrition plays a significant role in many metabolic and physiological changes during pregnancy. Women with CKD are at increased risk of nutrition deficiencies and metabolic issues than women without CKD. Currently, we lack evidence regarding metabolic and nutritional adaptations during pregnancy in women with CKD and how these adaptations relate to perinatal outcomes. In this review, dietary and supplementation recommendations for CKD in adults and pregnant women are summarized from current clinical guidelines. We present the main nutrition care practices that have been studied in CKD pregnancies. This review will be helpful to health professionals as a preliminary reference for nutrition assessment and therapy in pregnant women with CKD.
Dual-initiation promoters with intertwined canonical and TCT/TOP transcription start sites diversify transcript processing
Authors: Nepal Chirag , Hadzhiev Yavor , Balwierz Piotr , Tarifeño-Saldivia Estefanía , Cardenas Ryan , Wragg Joseph W. , Suzuki Ana-Maria , Carninci Piero , Peers Bernard , Lenhard Boris , Andersen Jesper B. , Müller Ferenc
Published: January 2020

Variations in transcription start site (TSS) selection reflect diversity of preinitiation complexes and can impact on post-transcriptional RNA fates. Most metazoan polymerase II-transcribed genes carry canonical initiation with pyrimidine/purine (YR) dinucleotide, while translation machinery-associated genes carry polypyrimidine initiator (5’-TOP or TCT). By addressing the developmental regulation of TSS selection in zebrafish we uncovered a class of dual-initiation promoters in thousands of genes, including snoRNA host genes. 5’-TOP/TCT initiation is intertwined with canonical initiation and used divergently in hundreds of dual-initiation promoters during maternal to zygotic transition. Dual-initiation in snoRNA host genes selectively generates host and snoRNA with often different spatio-temporal expression. Dual-initiation promoters are pervasive in human and fruit fly, reflecting evolutionary conservation. We propose that dual-initiation on shared promoters represents a composite promoter architecture, which can function both coordinately and divergently to diversify RNAs.
Is negative capacitance FET a steep-slope logic switch?
Authors: Cao Wei , Banerjee Kaustav
Published: January 2020

The negative-capacitance field-effect transistor(NC-FET) has attracted tremendous research efforts. However, the lack of a clear physical picture and design rule for this device has led to numerous invalid fabrications. In this work, we address this issue based on an unexpectedly concise and insightful analytical formulation of the minimum hysteresis-free subthreshold swing (SS), together with several important conclusions. Firstly, well-designed MOSFETs that have low trap density, low doping in the channel, and excellent electrostatic integrity, receive very limited benefit from NC in terms of achieving subthermionic SS. Secondly, quantum-capacitance is the limiting factor for NC-FETs to achieve hysteresis-free subthermionic SS, and FETs that can operate in the quantum-capacitance limit are desired platforms for NC-FET construction. Finally, a practical role of NC in FETs is to save the subthreshold and overdrive voltage losses. Our analysis and findings are intended to steer the NC-FET research in the right direction.
Cryptic variation in RNA-directed DNA-methylation controls lateral root development when auxin signalling is perturbed
Authors: Shahzad Zaigham , Eaglesfield Ross , Carr Craig , Amtmann Anna
Published: January 2020

Maintaining the right balance between plasticity and robustness in biological systems is important to allow adaptation while maintaining essential functions. Developmental plasticity of plant root systems has been the subject of intensive research, but the mechanisms underpinning robustness remain unclear. Here, we show that potassium deficiency inhibits lateral root organogenesis by delaying early stages in the formation of lateral root primordia. However, the severity of the symptoms arising from this perturbation varies within a natural population of Arabidopsis and is associated with the genetic variation in CLSY1, a key component of the RNA-directed DNA-methylation machinery. Mechanistically, CLSY1 mediates the transcriptional repression of a negative regulator of root branching, IAA27, and promotes lateral root development when the auxin-dependent proteolysis pathway fails. Our study identifies DNA-methylation-mediated transcriptional repression as a backup system for post-translational protein degradation which ensures robust development and performance of plants in a challenging environment.
Non-invasive optical control of endogenous Ca2+ channels in awake mice
Authors: Kim Sungsoo , Kyung Taeyoon , Chung Jae-Hee , Kim Nury , Keum Sehoon , Lee Jinsu , Park Hyerim , Kim Ho Min , Lee Sangkyu , Shin Hee-Sup , Heo Won Do
Published: January 2020

Optogenetic approaches for controlling Ca2+ channels provide powerful means for modulating diverse Ca2+-specific biological events in space and time. However, blue light-responsive photoreceptors are, in principle, considered inadequate for deep tissue stimulation unless accompanied by optic fiber insertion. Here, we present an ultra-light-sensitive optogenetic Ca2+ modulator, named monSTIM1 encompassing engineered cryptochrome2 for manipulating Ca2+ signaling in the brain of awake mice through non-invasive light delivery. Activation of monSTIM1 in either excitatory neurons or astrocytes of mice brain is able to induce Ca2+-dependent gene expression without any mechanical damage in the brain. Furthermore, we demonstrate that non-invasive Ca2+ modulation in neurons can be sufficiently and effectively translated into changes in behavioral phenotypes of awake mice.
Natural variation of an EF-hand Ca2+-binding-protein coding gene confers saline-alkaline tolerance in maize
Authors: Cao Yibo , Zhang Ming , Liang Xiaoyan , Li Fenrong , Shi Yunlu , Yang Xiaohong , Jiang Caifu
Published: January 2020

Sodium (Na+) toxicity is one of the major damages imposed on crops by saline-alkaline stress. Here we show that natural maize inbred lines display substantial variations in shoot Na+ contents and saline-alkaline (NaHCO3) tolerance, and reveal that ZmNSA1 (Na+Content under Saline-Alkaline Condition) confers shoot Na+ variations under NaHCO3 condition by a genome-wide association study. Lacking of ZmNSA1 promotes shoot Na+ homeostasis by increasing root Na+ efflux. A naturally occurred 4-bp deletion decreases the translation efficiency of ZmNSA1 mRNA, thus promotes Na+ homeostasis. We further show that, under saline-alkaline condition, Ca2+ binds to the EF-hand domain of ZmNSA1 then triggers its degradation via 26S proteasome, which in turn increases the transcripts levels of PM-H+-ATPases (MHA2 and MHA4), and consequently enhances SOS1 Na+/H+ antiporter-mediated root Na+ efflux. Our studies reveal the mechanism of Ca2+-triggered saline-alkaline tolerance and provide an important gene target for breeding saline-alkaline tolerant maize varieties.
Influence of energy gap between charge-transfer and locally excited states on organic long persistence luminescence
Authors: Lin Zesen , Kabe Ryota , Wang Kai , Adachi Chihaya
Published: January 2020

Organic long-persistent luminescence (LPL) is an organic luminescence system that slowly releases stored exciton energy as light. Organic LPL materials have several advantages over inorganic LPL materials in terms of functionality, flexibility, transparency, and solution-processability. However, the molecular selection strategies for the organic LPL system still remain unclear. Here we report that the energy gap between the lowest localized triplet excited state and the lowest singlet charge-transfer excited state in the exciplex system significantly controls the LPL performance. Changes in the LPL duration and spectra properties are systematically investigated for three donor materials having a different energy gap. When the energy level of the lowest localized triplet excited state is much lower than that of the charge-transfer excited state, the system exhibits a short LPL duration and clear two distinct emission features originating from exciplex fluorescence and donor phosphorescence.
Arf1-mediated lipid metabolism sustains cancer cells and its ablation induces anti-tumor immune responses in mice
Authors: Wang Guohao , Xu Junji , Zhao Jiangsha , Yin Weiqin , Liu Dayong , Chen WanJun , Hou Steven X.
Published: January 2020

Cancer stem cells (CSCs) may be responsible for treatment resistance, tumor metastasis, and disease recurrence. Here we demonstrate that the Arf1-mediated lipid metabolism sustains cells enriched with CSCs and its ablation induces anti-tumor immune responses in mice. Notably, Arf1 ablation in cancer cells induces mitochondrial defects, endoplasmic-reticulum stress, and the release of damage-associated molecular patterns (DAMPs), which recruit and activate dendritic cells (DCs) at tumor sites. The activated immune system finally elicits antitumor immune surveillance by stimulating T-cell infiltration and activation. Furthermore, TCGA data analysis shows an inverse correlation between Arf1 expression and T-cell infiltration and activation along with patient survival in various human cancers. Our results reveal that Arf1-pathway knockdown not only kills CSCs but also elicits a tumor-specific immune response that converts dying CSCs into a therapeutic vaccine, leading to durable benefits.
Imprinted Cdkn1c genomic locus cell-autonomously promotes cell survival in cerebral cortex development
Authors: Laukoter Susanne , Beattie Robert , Pauler Florian M. , Amberg Nicole , Nakayama Keiichi I. , Hippenmeyer Simon
Published: January 2020

The cyclin-dependent kinase inhibitor p57KIP2 is encoded by the imprinted Cdkn1c locus, exhibits maternal expression, and is essential for cerebral cortex development. How Cdkn1c regulates corticogenesis is however not clear. To this end we employ Mosaic Analysis with Double Markers (MADM) technology to genetically dissect Cdkn1c gene function in corticogenesis at single cell resolution. We find that the previously described growth-inhibitory Cdkn1c function is a non-cell-autonomous one, acting on the whole organism. In contrast we reveal a growth-promoting cell-autonomous Cdkn1c function which at the mechanistic level mediates radial glial progenitor cell and nascent projection neuron survival. Strikingly, the growth-promoting function of Cdkn1c is highly dosage sensitive but not subject to genomic imprinting. Collectively, our results suggest that the Cdkn1c locus regulates cortical development through distinct cell-autonomous and non-cell-autonomous mechanisms. More generally, our study highlights the importance to probe the relative contributions of cell intrinsic gene function and tissue-wide mechanisms to the overall phenotype.
δ13C of terrestrial vegetation records Toarcian CO2 and climate gradients
Authors: Ruebsam Wolfgang , Reolid Matías , Schwark Lorenz
Published: January 2020

Throughout Earth’s history, variations in atmospheric CO2 concentration modulated climate. Understanding changes in atmospheric carbon cycle is therefore pivotal in predicting consequences of recent global warming. Here, we report stable carbon isotopes (δ13C) of molecular land plant fossils complemented by bulk organic and inorganic carbon fractions for early Toarcian (Early Jurassic) sediments that coincided with global warming and a carbon cycle perturbation. The carbon cycle perturbation is expressed by a negative excursion in the δ13C records established for the different substrates. Based on differences in the magnitude of the carbon isotope excursion recorded in land plants and marine substrates we infer that the early Toarcian warming was paralleled by an increase in atmospheric CO2 levels from ~500 ppmv to ~1000 ppmv. Our data suggest that rising atmospheric CO2 levels resulted from the injection of  12C-enriched methane and its subsequent oxidation to CO2. Based on the cyclic nature of the CIE we concluded that methane was released from climate sensitive reservoirs, in particular permafrost areas. Moderate volcanic CO2 emissions led to a destabilization of the labile permafrost carbon pool triggering the onset of Toarcian climate change only. The main carbon cycle perturbation then subsequently was driven by a self-sustained demise of a carbon-rich cryosphere progressing from mid to high latitudes as reflected by latitudinal climate gradients recorded in land plant carbon isotopes.
Polarization perception in humans: on the origin of and relationship between Maxwell’s spot and Haidinger’s brushes
Authors: Misson Gary P. , Temple Shelby E. , Anderson Stephen J.
Published: January 2020

Under specific conditions of illumination and polarization, differential absorption of light by macular pigments is perceived as the entoptic phenomena of Maxwell’s spot (MS) or Haidinger’s brushes (HB). To simulate MS and HB, an existing computational model of polarization-dependent properties of the human macula was extended by incorporating neuronal adaptation to stabilized retinal images. The model predicted that polarized light modifies the appearance of MS leading to the perception of a novel phenomenon. The model also predicted a correlation between the observed diameters of MS and HB. Predictions were tested psychophysically in human observers, whose measured differences in the diameters of each entoptic phenomenon generated with depolarized and linearly polarized light were consistent with the model simulations. These findings support a common origin of each phenomenon, and are relevant to the clinical use of polarization stimuli in detecting and monitoring human eye disorders, including macular degeneration. We conclude: (i) MS and HB both result from differential light absorption through a radial diattenuator, compatible with the arrangement of macular pigments in Henle fibres; (ii) the morphology of MS is dependent on the degree of linear polarization; (iii) perceptual differences between MS and HB result from different states of neural adaptation.
Automated gigapixel circumferential surface microscopy of the prostate
Authors: Luethy Samuel , Tulman David B. , Brown J. Quincy
Published: January 2020

Positive surgical margins, or cancer cells found at the boundary of an excised tumor mass, are a significant problem in the management of many cancers resulting in worsened patient outcomes. The problem is exacerbated in organ sites such as the prostate, where unnecessarily wide local excisions can result in significant deterioration of post-operative quality of life due to collateral damage to neighboring structures. Yet, at the same time, incomplete tumor removal results in worsened prognosis and need for additional interventions. Here, we report the design and development of a rapid and completely automated system for intraoperative gigapixel ex vivo microscopy of the circumferential surgical prostate margin within intra-operative timeframes, called the Automated Prostate Positioning System (APPS). The APPS leverages the rotational geometry of the prostate and high speed structured illumination microscopy (SIM) to generate continuous gigapixel panoramas of the fresh intact prostate circumference, including areas of the prostate adjacent to the neurovascular bundles, the rectum, and the bladder wall. Our previous work using SIM and a manual prostate handling method demonstrated the promise of the imaging technique for accurate detection of positive surgical margins. Our work here advances the technology toward clinical adoption, by demonstrating 10% greater tissue surface coverage fraction, 1.6× faster imaging throughput, and reduced number of required operator steps, compared to our prior approach. The APPS may be operated by a single person in the operating room suite within intraoperative time limits, while simultaneously delivering nearly two orders of magnitude higher tissue surface coverage than destructive and labor-intensive frozen section analysis techniques.
A new possible megalosauroid theropod from the Middle Jurassic Xintiangou Formation of Chongqing, People’s Republic of China and its implication for early tetanuran evolution
Authors: Dai Hui , Benson Roger , Hu Xufeng , Ma Qingyu , Tan Chao , Li Ning , Xiao Ming , Hu Haiqian , Zhou Yuxuan , Wei Zhaoying , Zhang Feng , Jiang Shan , Li Deliang , Peng Guangzhao , Yu Yilun , Xu Xing
Published: January 2020

Tetanurae is a special group of theropod dinosaurs that originated by the late Early Jurassic. It includes several early-diverging groups of generally large-bodied predators (megalosauroids, allosauroids, tyrannosauroid coelurosaurs) as well as morphologically disparate small-bodied coelurosaurs, including birds. Aspects of the evolutionary history of tetanurans remain contested, including the topology of their deep phylogenetic divergences (among Megalosauroidea, Allosauroidea and Coelurosauria). We report a new theropod, Yunyangosaurus puanensis gen. et sp. nov., based on a fragmentary specimen recovered from the Middle Jurassic Xintiangou Formation of Chongqing, southwestern China. It shares several features uniquely with some megalosauroids (the clade of megalosaurids + spinosaurids + piatnitzkysaurids), such as prominent rims around the anterior articular surfaces of cervical centra and bifurcated anterior dorsal neural spines (present in piatnitzkysaurids). Nevertheless, it also shows several features that are rare or absent among megalosauroids and more crownward tetanurans, including prominent spinopostyzgopophyseal laminae (also present in non-tetanurans and metriacanthosaurid allosauroids), flat anterior articular surfaces of the cervical centra (also present in piatnitzkysaurids and some earlier-diverging tetanurans), and the presence of a posterior pneumatic foramen or fossa (absent in most tetanurans, but sporadically present in some cervical vertebrae of piatnitzkysaurids). Yunyangosaurus therefore presents a combination of derived and apparently primitive character states that are not seen in other theropods. This suggests that patterns of morphological evolution associated with deep tetanuran divergences were more complex than currently recognized, with implications for understanding the character evolution in theropods.
Selective and Recyclable Congo Red Dye Adsorption by Spherical Fe3O4 Nanoparticles Functionalized with 1,2,4,5-Benzenetetracarboxylic Acid
Authors: Chatterjee Sobhan , Guha Nikita , Krishnan Sarathkumar , Singh Amrendra K. , Mathur Pradeep , Rai Dhirendra K.
Published: January 2020

In this study, the new material Fe3O4@BTCA has been synthesized by immobilization of 1,2,4,5-Benzenetetracarboxylic acid (BTCA) on the surface of Fe3O4 NPs, obtained by co-precipitation of FeCl3.6H2O and FeCl2.4H2O in the basic conditions. Characterization by P-XRD, FE-SEM, and TEM confirm Fe3O4 has a spherical crystalline structure with an average diameter of 15 nm, which after functionalization with BTCA, increases to 20 nm. Functionalization also enhances the surface area and surface charge of the material, confirmed by BET and zeta potential analyses, respectively. The dye adsorption capacity of Fe3O4@BTCA has been investigated for three common dyes; Congo red (C.R), Methylene blue (M.B), and Crystal violet (C.V). The adsorption studies show that the material rapidly and selectively adsorbs C.R dye with very high adsorption capacity (630 mg/g), which is attributed to strong H-bonding ability of BTCA with C.R dye as indicated by adsorption mechanism study. The material also shows excellent recyclability without any considerable loss of adsorption capacity. Adsorption isotherm and kinetic studies suggest that the adsorption occurs by the Langmuir adsorption model following pseudo-second-order adsorption kinetics.
Photoplethysmography based atrial fibrillation detection: a review
Authors: Pereira Tania , Tran Nate , Gadhoumi Kais , Pelter Michele M. , Do Duc H. , Lee Randall J. , Colorado Rene , Meisel Karl , Hu Xiao
Published: January 2020

Atrial fibrillation (AF) is a cardiac rhythm disorder associated with increased morbidity and mortality. It is the leading risk factor for cardioembolic stroke and its early detection is crucial in both primary and secondary stroke prevention. Continuous monitoring of cardiac rhythm is today possible thanks to consumer-grade wearable devices, enabling transformative diagnostic and patient management tools. Such monitoring is possible using low-cost easy-to-implement optical sensors that today equip the majority of wearables. These sensors record blood volume variations—a technology known as photoplethysmography (PPG)—from which the heart rate and other physiological parameters can be extracted to inform about user activity, fitness, sleep, and health. Recently, new wearable devices were introduced as being capable of AF detection, evidenced by large prospective trials in some cases. Such devices would allow for early screening of AF and initiation of therapy to prevent stroke. This review is a summary of a body of work on AF detection using PPG. A thorough account of the signal processing, machine learning, and deep learning approaches used in these studies is presented, followed by a discussion of their limitations and challenges towards clinical applications.
Structure and dynamics of the E. coli chemotaxis core signaling complex by cryo-electron tomography and molecular simulations
Authors: Cassidy C. Keith , Himes Benjamin A. , Sun Dapeng , Ma Jun , Zhao Gongpu , Parkinson John S. , Stansfeld Phillip J. , Luthey-Schulten Zaida , Zhang Peijun
Published: January 2020

To enable the processing of chemical gradients, chemotactic bacteria possess large arrays of transmembrane chemoreceptors, the histidine kinase CheA, and the adaptor protein CheW, organized as coupled core-signaling units (CSU). Despite decades of study, important questions surrounding the molecular mechanisms of sensory signal transduction remain unresolved, owing especially to the lack of a high-resolution CSU structure. Here, we use cryo-electron tomography and sub-tomogram averaging to determine a structure of the Escherichia coli CSU at sub-nanometer resolution. Based on our experimental data, we use molecular simulations to construct an atomistic model of the CSU, enabling a detailed characterization of CheA conformational dynamics in its native structural context. We identify multiple, distinct conformations of the critical P4 domain as well as asymmetries in the localization of the P3 bundle, offering several novel insights into the CheA signaling mechanism.
Anti-Zeno quantum advantage in fast-driven heat machines
Authors: Mukherjee Victor , Kofman Abraham G. , Kurizki Gershon
Published: January 2020

Developing quantum machines which can outperform their classical counterparts, thereby achieving quantum supremacy or quantum advantage, is a major aim of the current research on quantum thermodynamics and quantum technologies. Here, we show that a fast-modulated cyclic quantum heat machine operating in the non-Markovian regime can lead to significant heat current and power boosts induced by the anti-Zeno effect. Such boosts signify a quantum advantage over almost all heat machines proposed thus far that operate in the conventional Markovian regime, where the quantumness of the system-bath interaction plays no role. The present effect owes its origin to the time-energy uncertainty relation in quantum mechanics, which may result in enhanced system-bath energy exchange for modulation periods shorter than the bath correlation-time.
Sensitive and selective detection of microRNA in complex biological samples based on protein-enhanced fluorescence anisotropy
Authors: Li Yan , Sun Yao , Ye Jieyun , Pan Fengping , Peng Bo , Li Haiqiang , Zhang Mingming , Xu Yan
Published: January 2020

A molecular mass amplifying strategy to construct a fluorescence anisotropy sensor for the detection of microRNA with high sensitivity and selectivity in complex biological samples was proposed.
The mesoscale regulation of β-NaYF4:Yb3+/Er3+ with desired size and morphology via introducing Li+/K+ into a hydrothermal environment
Authors: Yang Sheng , Duan Meng , Li Yongying , Ding Xueying , Shen Yulan , Cheng Hui , Gao Guo , Cui Daxiang
Published: January 2020

The mesoscale regulation of NaYF4:Yb3+/Er3+ in a hydrothermal system was developed. The evolution of the product has several stages: nucleation, aggregation, orientation growth and ripening.
High-throughput computational screening for solid-state Li-ion conductors
Authors: Kahle Leonid , Marcolongo Aris , Marzari Nicola
Published: January 2020

Atomistic simulations are employed to screen experimental structural repositories for fast Li-ion conductors, finding new candidate solid-state electrolyte materials.
Conformal organic–inorganic semiconductor composites for flexible thermoelectrics
Authors: Xu Qing , Qu Sanyin , Ming Chen , Qiu Pengfei , Yao Qin , Zhu Chenxi , Wei Tian-Ran , He Jian , Shi Xun , Chen Lidong
Published: January 2020

The development of flexible organic–inorganic thermoelectric composites constitutes a promising material approach toward harvesting heat from the human body or environment to power wearable electronics.
Trends in heavy metals, polychlorinated biphenyls and toxicity from sediment cores of the inner River Thames estuary, London, UK
Authors: Vane Christopher H. , Turner Grenville H. , Chenery Simon R. , Richardson Martin , Cave Mark C. , Terrington Ricky , Gowing Charles J. B. , Moss-Hayes Vicky
Published: January 2020

River islands (Ait or Eyot) within the inner tidal Thames serve as unique recorders of current and historical estuarine chemical pollution.
Thiolated silica nanoadsorbents enable ultrahigh and fast decontamination of mercury(ii): understanding the contribution of thiol moieties' density and accessibility on adsorption performance
Authors: Kalantari Mohammad , Gu Zhengying , Cao Yuxue , Lei Chang , Zhang Jun
Published: January 2020

Silica nanoadsorbents with a gradient of sulfur content with higher density at the external part enable effective decontamination of mercury.
Transcriptome profiling of hiPSC-derived LSECs with nanoCAGE
Authors: Danoy Mathieu , Poulain Stéphane , Koui Yuta , Tauran Yannick , Scheidecker Benedikt , Kido Taketomo , Miyajima Atsushi , Sakai Yasuyuki , Plessy Charles , Leclerc Eric
Published: January 2020

As a response to the challenge of the in vitro maintenance of liver endothelial cells, we have used hiPSCs-derived LSECs and have measured their performance by comparing them to their primary counterpart using the nanoCAGE technology.
Au–InSe van der Waals Schottky junctions with ultralow reverse current and high photosensitivity
Authors: Hu Siqi , Zhang Qiao , Luo Xiaoguang , Zhang Xutao , Wang Tao , Cheng Yingchun , Jie Wanqi , Zhao Jianlin , Mei Ting , Gan Xuetao
Published: January 2020

The Schottky junction, composed of a rectifying metal–semiconductor interface, is an essential component for microelectronic and optoelectronic devices.
Chinese hydrangea lantern-like Co9S8@MoS2composites with enhanced lithium-ion battery properties
Authors: Yang Kai , Mei Tao , Chen Zihe , Xiong Man , Wang Xuhui , Wang Jianying , Li Jinhua , Yu Li , Qian Jingwen , Wang Xianbao
Published: January 2020

Chinese hydrangea lantern-like Co9S8@MoS2composites are prepared by a facile solvothermal method.
Quinone/ester-based oxygen functional group-incorporated full carbon Li-ion capacitor for enhanced performance
Authors: Cai Peng , Zou Kangyu , Zou Guoqiang , Hou Hongshuai , Ji Xiaobo
Published: January 2020

Lithium ion capacitors (LICs) are regarded as one of the most promising energy storage devices since they can bridge the gap between lithium ion batteries and supercapacitors.
Hypervalent iodine promoted ortho diversification: 2-aryl benzimidazole, quinazoline and imidazopyridine as directing templates
Authors: Saha Moumita , Das Asish R.
Published: January 2020

(Diacetoxyiodo)benzene (PIDA) promoted Pd-catalyzed efficient ortho C(sp2)–H acetoxylation, arylation, iodination and nitration are achieved using (NH)-free 2-substituted benzimidazole, quinazoline and imidazopyridine as chelating substrates.
An amino acid-assisted approach to fabricate nanosized hierarchical TS-1 zeolites for efficient oxidative desulfurization
Authors: Yang Guoju , Han Ji , Qiu Ziyi , Chen Xiaoxin , Feng Zhaochi , Yu Jihong
Published: January 2020

A facile amino acid-assisted approach coupled with two-step rota-crystallization has been developed to prepare nanosized hierarchical TS-1 zeolites, which are free of anatase TiO2 and possess abundant secondary meso-/macropores.
Ionic liquid-functionalized LDH as catalytic-initiating nanoparticles for microwave-activated ring opening polymerization of ε-caprolactone
Authors: Bujok Sonia , Konefał Magdalena , Abbrent Sabina , Pavlova Ewa , Svoboda Jan , Trhlíková Olga , Walterová Zuzana , Beneš Hynek
Published: January 2020

Layered double hydroxides with ionic liquid as highly active catalytic-initiating system for microwave-assisted ring opening polymerization of ε-caprolactone.
A programmable chemical switch based on triggerable Michael acceptors
Authors: Zhuang Jiaming , Zhao Bo , Meng Xiangxi , Schiffman Jessica D. , Perry Sarah L. , Vachet Richard W. , Thayumanavan S.
Published: January 2020

A triggerable Michael acceptor (TMAc) with programmable reactivity and reversibility for simultaneous coupling and decoupling has been developed for selective protein modification, self-immolative linker and orthogonally addressable hydrogel.
Biomimetic O2 adsorption in an iron metal–organic framework for air separation
Authors: Reed Douglas A. , Xiao Dianne J. , Jiang Henry Z. H. , Chakarawet Khetpakorn , Oktawiec Julia , Long Jeffrey R.
Published: January 2020

Bio-inspired motifs for gas binding and small molecule activation can be used to design more selective adsorbents for gas separation applications.
SAC3B is a target of CML19, the centrin 2 of Arabidopsis thaliana
Authors: Pedretti Marco , Conter Carolina , Dominici Paola , Astegno Alessandra
Published: January 2020

Arabidopsis centrin 2, also known as calmodulin-like protein 19 (CML19), is a member of the EF-hand superfamily of calcium (Ca2+)-binding proteins. In addition to the notion that CML19 interacts with the nucleotide excision repair protein RAD4, CML19 was suggested to be a component of the transcription export complex 2 (TREX-2) by interacting with SAC3B. However, the molecular determinants of this interaction have remained largely unknown. Herein, we identified a CML19-binding site within the C-terminus of SAC3B and characterized the binding properties of the corresponding 26-residue peptide (SAC3Bp), which exhibits the hydrophobic triad centrin-binding motif in a reversed orientation (I8W4W1). Using a combination of spectroscopic and calorimetric experiments, we shed light on the SAC3Bp–CML19 complex structure in solution. We demonstrated that the peptide interacts not only with Ca2+-saturated CML19, but also with apo-CML19 to form a protein–peptide complex with a 1 : 1 stoichiometry. Both interactions involve hydrophobic and electrostatic contributions and include the burial of Trp residues of SAC3Bp. However, the peptide likely assumes different conformations upon binding to apo-CML19 or Ca2+-CML19. Importantly, the peptide dramatically increases the affinity for Ca2+ of CML19, especially of the C-lobe, suggesting that in vivo the protein would be Ca2+-saturated and bound to SAC3B even at resting Ca2+-levels. Our results, providing direct evidence that Arabidopsis SAC3B is a CML19 target and proposing that CML19 can bind to SAC3B through its C-lobe independent of a Ca2+ stimulus, support a functional role for these proteins in TREX-2 complex and mRNA export.
Comparative structure, dynamics and evolution of acyl-carrier proteins from Borrelia burgdorferi, Brucella melitensis and Rickettsia prowazekii
Authors: Barnwal Ravi P. , Kaur Mandeep , Heckert Alec , Gartia Janeka , Varani Gabriele
Published: January 2020

Acyl carrier proteins (ACPs) are small helical proteins found in all kingdoms of life, primarily involved in fatty acid and polyketide biosynthesis. In eukaryotes, ACPs are part of the fatty acid synthase (FAS) complex, where they act as flexible tethers for the growing lipid chain, enabling access to the distinct active sites in FAS. In the type II synthesis systems found in bacteria and plastids, these proteins exist as monomers and perform various processes, from being a donor for synthesis of various products such as endotoxins, to supplying acyl chains for lipid A and lipoic acid FAS (quorum sensing), but also as signaling molecules, in bioluminescence and activation of toxins. The essential and diverse nature of their functions makes ACP an attractive target for antimicrobial drug discovery. Here, we report the structure, dynamics and evolution of ACPs from three human pathogens: Borrelia burgdorferi, Brucella melitensis and Rickettsia prowazekii, which could facilitate the discovery of new inhibitors of ACP function in pathogenic bacteria.
Import pathways of the mannityl-opines into the bacterial pathogen Agrobacterium tumefaciens: structural, affinity and in vivo approaches
Authors: Vigouroux Armelle , Doré Jeanne , Marty Loïc , Aumont-Nicaise Magali , Legrand Pierre , Dessaux Yves , Vial Ludovic , Moréra Solange
Published: January 2020

Agrobacterium tumefaciens pathogens use specific compounds denoted opines as nutrients in their plant tumor niche. These opines are produced by the host plant cells genetically modified by agrobacteria. They are imported into bacteria via solute-binding proteins (SBPs) in association with ATP-binding cassette transporters. The mannityl-opine family encompasses mannopine, mannopinic acid, agropine and agropinic acid. Structural and affinity data on mannopinic acid bound to SBPs are currently lacking while those of the three others mannityl opines are available. We investigated the molecular basis of two pathways for mannopinic acid uptake. MoaA was proposed as the specific SBP for mannopinic acid import in mannityl opines-assimilating agrobacteria, which was validated here using genetic studies and affinity measurements. We structurally characterized the mannopinic acid-binding mode of MoaA in two crystal forms at 2.05 and 1.57 Å resolution. We demonstrated that the non-specific SBP MotA, so far characterized as mannopine and Amadori compound importer, was also able to transport mannopinic acid. The structure of MotA bound to mannopinic acid at 2.2 Å resolution defines a different mannopinic acid-binding signature, similar to that of mannopine. Combining in vitro and in vivo approaches, this work allowed us to complete the characterization of the mannityl-opines assimilation pathways, highlighting the important role of two dual imports of agropinic and mannopinic acids. Our data shed new light on how the mannityl-opines contribute to the establishment of the ecological niche of agrobacteria from the early to the late stages of tumor development.
Using single-cell RNA sequencing to unravel cell lineage relationships in the respiratory tract
Authors: Zaragosi L.E. , Deprez M. , Barbry P.
Published: January 2020

The respiratory tract is lined by a pseudo-stratified epithelium from the nose to terminal bronchioles. This first line of defense of the lung against external stress includes five main cell types: basal, suprabasal, club, goblet and multiciliated cells, as well as rare cells such as ionocytes, neuroendocrine and tuft/brush cells. At homeostasis, this epithelium self-renews at low rate but is able of fast regeneration upon damage. Airway epithelial cell lineages during regeneration have been investigated in the mouse by genetic labeling, mainly after injuring the epithelium with noxious agents. From these approaches, basal cells have been identified as progenitors of club, goblet and multiciliated cells, but also of ionocytes and neuroendocrine cells. Single-cell RNA sequencing, coupled to lineage inference algorithms, has independently allowed the establishment of comprehensive pictures of cell lineage relationships in both mouse and human. In line with genetic tracing experiments in mouse trachea, studies using single-cell RNA sequencing (RNAseq) have shown that basal cells first differentiate into club cells, which in turn mature into goblet cells or differentiate into multiciliated cells. In the human airway epithelium, single-cell RNAseq has identified novel intermediate populations such as deuterosomal cells, ‘hybrid’ mucous-multiciliated cells and progenitors of rare cells. Novel differentiation dynamics, such as a transition from goblet to multiciliated cells have also been discovered. The future of cell lineage relationships in the respiratory tract now resides in the combination of genetic labeling approaches with single-cell RNAseq to establish, in a definitive manner, the hallmarks of cellular lineages in normal and pathological situations.
Mechanisms and consequences of protein cysteine oxidation: the role of the initial short-lived intermediates
Authors: Turell Lucia , Zeida Ari , Trujillo Madia
Published: January 2020

Thiol groups in protein cysteine (Cys) residues can undergo one- and two-electron oxidation reactions leading to the formation of thiyl radicals or sulfenic acids, respectively. In this mini-review we summarize the mechanisms and kinetics of the formation of these species by biologically relevant oxidants. Most of the latter react with the deprotonated form of the thiol. Since the pKa of the thiols in protein cysteines are usually close to physiological pH, the thermodynamics and the kinetics of their oxidation in vivo are affected by the acidity of the thiol. Moreover, the protein microenvironment has pronounced effects on cysteine residue reactivity, which in the case of the oxidation mediated by hydroperoxides, is known to confer specificity to particular protein cysteines. Despite their elusive nature, both thiyl radicals and sulfenic acids are involved in the catalytic mechanism of several enzymes and in the redox regulation of protein function and/or signaling pathways. They are usually short-lived species that undergo further reactions that converge in the formation of different stable products, resulting in several post-translational modifications of the protein. Some of these can be reversed through the action of specific cellular reduction systems. Others damage the proteins irreversibly, and can make them more prone to aggregation or degradation.
Effective automated method for detection and suppression of muscle artefacts from single‐channel EEG signal
Authors: Saini Manali , Satija Udit , Upadhayay Madhur Deo
Published: January 2020

This Letter proposes an automated method for the detection and suppression of muscle artefacts (MAs) in the single‐channel electroencephalogram (EEG) signal based on variational mode decomposition (VMD) and zero crossings count threshold criterion without the use of reference electromyogram (EMG). The proposed method involves three major steps: decomposition of the input EEG signal into two modes using VMD; detection of MAs based on zero crossings count thresholding in the second mode; retention of the first mode as MAs‐free EEG signal only after detection of MAs in the second mode. The authors evaluate the robustness of the proposed method on a variety of EEG and EMG signals taken from publicly available databases, including Mendeley database, epileptic Bonn database and EEG during mental arithmetic tasks database (EEGMAT). Evaluation results using different objective performance metrics depict the superiority of the proposed method as compared to existing methods while preserving the clinical features of the reconstructed EEG signal.