bluuebunny/crossref_metadata_2025_split huggingface dataset:
Particle-Size Variability of Aerosol Iron and Impact on Iron Solubility and Dry Deposition Fluxes to the Arctic Ocean
Authors: Gao Yuan , Marsay Christopher M. , Yu Shun , Fan Songyun , Mukherjee Pami , Buck Clifton S. , Landing William M. 
Published: November 2019

AbstractThis study provides unique insights into the properties of iron (Fe) in the marine atmosphere over the late summertime Arctic Ocean. Atmospheric deposition of aerosols can deliver Fe, a limiting micronutrient, to the remote ocean. Aerosol particle size influences aerosol Fe fractional solubility and air-to-sea deposition rate. Size-segregated aerosols were collected during the 2015 US GEOTRACES cruise in the Arctic Ocean. Results show that aerosol Fe had a single-mode size distribution, peaking at 4.4 µm in diameter, suggesting regional dust sources of Fe around the Arctic Ocean. Estimated dry deposition rates of aerosol Fe decreased from 6.1 µmol m−2 yr−1 in the areas of ~56°N–80°N to 0.73 µmol m−2 yr−1 in the areas north of 80°N. Aerosol Fe solubility was higher in fine particles (<1 µm) which were observed mainly in the region north of 80°N and coincided with relatively high concentrations of certain organic aerosols, suggesting interactions between aerosol Fe and organic ligands in the high-latitude Arctic atmosphere. The average molar ratio of Fe to titanium (Ti) was 2.4, substantially lower than the typical crustal ratio of 10. We speculate that dust sources around the Arctic Ocean may have been altered because of climate warming.
Development of a histamine aptasensor for food safety monitoring
Authors: Dwidar Mohammed , Yokobayashi Yohei 
Published: November 2019

AbstractHistamine produced by bacteria through decarboxylation of histidine in spoiled foods such as fish is known to cause food poisoning. Therefore, accurate and facile measurement of histamine is of practical importance. Using the recently discovered RNA aptamer that specifically recognizes histamine (A1-949 aptamer), we developed an aptasensor based on the structure-switching mechanism. Specifically, the aptamer A1-949 was fluorescently labeled at the 5′ end and hybridized with a short quencher DNA strand that is partially complementary to the aptamer. The quencher strand was modified with a fluorescence quencher at its 3′ terminus. Displacement of the quencher strand upon histamine binding results in an increased fluorescence. After optimizing the assay condition, the enantiomeric version of the aptasensor (L-RNA and L-DNA) was synthesized which could detect the achiral analyte with identical sensitivity and improved biochemical stability. The aptasensor performance was validated by measuring fish samples spiked with known concentrations of histamine. Finally, histamine content in spoiled fish samples was measured, and the results were compared with the measurements using a commercial enzymatic assay kit.
Sex-dependent VEGF expression underlies variations in human pluripotent stem cell to endothelial progenitor differentiation
Authors: Randolph Lauren N. , Bao Xiaoping , Oddo Michael , Lian Xiaojun Lance 
Published: November 2019

AbstractHuman pluripotent stem cells (hPSCs) offer tremendous promise in tissue engineering and cell-based therapies because of their unique combination of two properties: pluripotency and a high proliferative capacity. To realize this potential, development of efficient hPSC differentiation protocols is required. In this work, sex-based differences are identified in a GSK3 inhibitor based endothelial progenitor differentiation protocol. While male hPSCs efficiently differentiate into CD34 + CD31+ endothelial progenitors upon GSK3 inhibition, female hPSCs showed limited differentiation capacity using this protocol. Using VE-cadherin-GFP knockin reporter cells, female cells showed significantly increased differentiation efficiency when treated with VEGF during the second stage of endothelial progenitor differentiation. Interestingly, male cells showed no significant change in differentiation efficiency with VEGF treatment, but did show augmented early activation of VE-cadherin expression. A sex-based difference in endogenous expression of VEGF was identified that is likely the underlying cause of discrepancies in sex-dependent differentiation efficiency. These findings highlight the importance of sex differences in progenitor biology and the development of new stem cell differentiation protocols.
Longitudinal OCT and OCTA monitoring reveals accelerated regression of hyaloid vessels in retinal degeneration 10 (rd10) mice
Authors: Kim Tae-Hoon , Son Taeyoon , Le David , Yao Xincheng 
Published: November 2019

AbstractThe hyaloid vascular system (HVS) is known to have an important role in eye development. However, physiological mechanisms of HVS regression and their correlation with developmental eye disorders remain unclear due to technical limitations of conventional ending point examination with fixed tissues. Here, we report comparative optical coherence tomography (OCT) and OCT angiography (OCTA) monitoring of HVS regression in wild-type and retinal degeneration 10 (rd10) mice. Longitudinal OCTA monitoring revealed accelerated regression of hyaloid vessels correlated with retinal degeneration in rd10. Quantitative OCT measurement disclosed significant distortions of both retinal thickness and the vitreous chamber in rd10 compared to WT mice. These OCT/OCTA observations confirmed the close relationship between HVS physiology and retinal neurovascular development. The distorted HVS regression might result from retinal hyperoxia or dopamine abnormality due to retinal remodeling in rd10 retina. By providing a noninvasive imaging platform for longitudinal monitoring of HVS regression, further OCT/OCTA study may lead to in-depth understanding of the physiological mechanisms of HVS regression in normal and diseased eyes, which is not only important for advanced study of the nature of the visual system but also may provide insights into the development of better treatment protocols of congenital eye disorders.
Serotonin 5-HT2C Receptor Cys23Ser Single Nucleotide Polymorphism Associates with Receptor Function and Localization In Vitro
Authors: Land Michelle A. , Chapman Holly L. , Davis-Reyes Brionna D. , Felsing Daniel E. , Allen John A. , Moeller F. Gerard , Elferink Lisa A. , Cunningham Kathryn A. , Anastasio Noelle C. 
Published: November 2019

AbstractA non-synonymous single nucleotide polymorphism of the human serotonin 5-HT2Creceptor (5-HT2CR) gene that converts a cysteine to a serine at amino acid codon 23 (Cys23Ser) appears to impact 5-HT2CR pharmacology at a cellular and systems level. We hypothesized that the Cys23Ser alters 5-HT2CR intracellular signaling via changes in subcellular localizationin vitro. Using cell lines stably expressing the wild-type Cys23 or the Ser23 variant, we show that 5-HT evokes intracellular calcium release with decreased potency and peak response in the Ser23 versus the Cys23 cell lines. Biochemical analyses demonstrated lower Ser23 5-HT2CR plasma membrane localization versus the Cys23 5-HT2CR. Subcellular localization studies demonstrated O-linked glycosylation of the Ser23 variant, but not the wild-type Cys23, may be a post-translational mechanism which alters its localization within the Golgi apparatus. Further, both the Cys23 and Ser23 5-HT2CR are present in the recycling pathway with the Ser23 variant having decreased colocalization with the early endosome versus the Cys23 allele. Agonism of the 5-HT2CR causes the Ser23 variant to exit the recycling pathway with no effect on the Cys23 allele. Taken together, the Ser23 variant exhibits a distinct pharmacological and subcellular localization profile versus the wild-type Cys23 allele, which could impact aspects of receptor pharmacology in individuals expressing the Cys23Ser SNP.
Crystal structure of suboptimal viral fragments of Epstein Barr Virus Rta peptide-HLA complex that stimulate CD8 T cell response
Authors: Huan Xuelu , Zhuo Ziyi , Xiao Ziwei , Ren Ee Chee 
Published: November 2019

AbstractPeptides presented by Human leukocyte antigen (HLA) class-I molecules are generally 8–10 amino acids in length. However, the predominant pool of peptide fragments generated by proteasomes is less than 8 amino acids in length. Using the Epstein - Barr virus (EBV) Rta-epitope (ATIGTAMYK, residues 134–142) restricted by HLA-A*11:01 which generates a strong immunodominant response, we investigated the minimum length of a viral peptide that can constitute a viral epitope recognition by CD8 T cells. The results showed that Peripheral blood mononuclear cells (PBMCs) from healthy donors can be stimulated by a viral peptide fragment as short as 4-mer (AMYK), together with a 5-mer (ATIGT) to recapitulate the full length EBV Rta epitope. This was confirmed by generating crystals of the tetra-complex (2 peptides, HLA and β2-microglobulin). The solved crystal structure of HLA-A*11:01 in complex with these two short peptides revealed that they can bind in the same orientation similar to parental peptide (9-mer) and the free ends of two short peptides acquires a bulged conformation that is directed towards the T cell receptor. Our data shows that suboptimal length of 4-mer and 5-mer peptides can complement each other to form a stable peptide-MHC (pMHC) complex.
The unexpected importance of the fifth digit during stone tool production
Authors: Key Alastair J. M. , Dunmore Christopher J. , Marzke Mary W. 
Published: November 2019

AbstractUnique anatomical features of the human hand facilitate our ability to proficiently and forcefully perform precision grips and in-hand manipulation of objects. Extensive research has been conducted into the role of digits one to three during these manual behaviours, and the origin of the highly derived first digit anatomy that facilitates these capabilities. Stone tool production has long been thought a key influence in this regard. Despite previous research stressing the unique derived morphology of the human fifth digit little work has investigated why humans alone display these features. Here we examine the recruitment frequency, loading magnitude, and loading distribution of all digits on the non-dominant hand of skilled flintknappers during four technologically distinct types of Lower Palaeolithic stone tool production. Our data reveal the fifth digit to be heavily and frequently recruited during all studied behaviours. It occasionally incurred pressures, and was used in frequencies, greater or equal to those of the thumb, and frequently the same or greater than those of the index finger. The fifth digit therefore appears key to >2 million years of stone tool production activities, a behaviour that likely contributed to the derived anatomy observed in the modern human fifth ray.
Frequency-Diverse Computational Direction of Arrival Estimation Technique
Authors: Yurduseven Okan , Abbasi Muhammad Ali Babar , Fromenteze Thomas , Fusco Vincent 
Published: November 2019

AbstractWe present a frequency-diverse based direction of arrival (DoA) estimation technique for millimetre-wave (mmW) 5G channel sounding. Frequency-diversity enables the creation of spatially incoherent radiation masks to encode the plane-wave signals incident on the radar aperture using a single antenna. Leveraging the frequency-diversity concept, spatial information of the plane-wave projections on the radar aperture is retrieved, resulting in high-fidelity DoA estimations by means of a simple Fourier transform operation applied to the retrieved plane-wave projection patterns. It is demonstrated that using the frequency-diversity concept, DoA estimation can be achieved through a simple frequency sweep, compressing the incoming plane-waves into a single channel through the transfer function of the radar aperture. This results in a significant simplification in the system hardware, requiring only a single antenna to achieve DoA estimation. It is also shown that the proposed technique can simultaneously detect the DoA information for multiple sources with a diffraction limited resolution.
ClpP protease activation results from the reorganization of the electrostatic interaction networks at the entrance pores
Authors: Mabanglo Mark F. , Leung Elisa , Vahidi Siavash , Seraphim Thiago V. , Eger Bryan T. , Bryson Steve , Bhandari Vaibhav , Zhou Jin Lin , Mao Yu-Qian , Rizzolo Kamran , Barghash Marim M. , Goodreid Jordan D. , Phanse Sadhna , Babu Mohan , Barbosa Leandro R. S. , Ramos Carlos H. I. , Batey Robert A. , Kay Lewis E. , Pai Emil F. , Houry Walid A. 
Published: November 2019

AbstractBacterial ClpP is a highly conserved, cylindrical, self-compartmentalizing serine protease required for maintaining cellular proteostasis. Small molecule acyldepsipeptides (ADEPs) and activators of self-compartmentalized proteases 1 (ACP1s) cause dysregulation and activation of ClpP, leading to bacterial cell death, highlighting their potential use as novel antibiotics. Structural changes in Neisseria meningitidis and Escherichia coli ClpP upon binding to novel ACP1 and ADEP analogs were probed by X-ray crystallography, methyl-TROSY NMR, and small angle X-ray scattering. ACP1 and ADEP induce distinct conformational changes in the ClpP structure. However, reorganization of electrostatic interaction networks at the ClpP entrance pores is necessary and sufficient for activation. Further activation is achieved by formation of ordered N-terminal axial loops and reduction in the structural heterogeneity of the ClpP cylinder. Activating mutations recapitulate the structural effects of small molecule activator binding. Our data, together with previous findings, provide a structural basis for a unified mechanism of compound-based ClpP activation.
Transcriptional programming and T cell receptor repertoires distinguish human lung and lymph node memory T cells
Authors: Schoettler Nathan , Hrusch Cara L , Blaine Kelly M , Sperling Anne I , Ober Carole 
Published: November 2019

AbstractAntigen-specific memory T cells persist for years after exposure to a pathogen and provide effective recall responses. Many memory T cell subsets have been identified and differ in abundance throughout tissues. This study focused on CD4 and CD8 memory T cells from paired human lung and lung draining lymph node (LDLN) samples and identified substantial differences in the transcriptional landscape of these subsets, including higher expression of an array of innate immune receptors in lung T cells which were further validated by flow cytometry. Using T cell receptor analysis, we determined the clonal overlap between memory T cell subsets within the lung and within the LDLN, and this was greater than the clonal overlap observed between memory T cell subsets compared across tissues. Our results suggest that lung and LDLN memory T cells originate from different precursor pools, recognize distinct antigens and likely have separate roles in immune responses.
Docosahexaenoic acid slows inflammation resolution and impairs the quality of healed skin tissue
Authors: Candreva Thamiris , Kühl Carolina M.C. , Burger Beatriz , dos Anjos Mariah B.P. , Torsoni Márcio A. , Consonni Sílvio R. , Crisma Amanda R. , Fisk Helena L. , Calder Philip C. , de Mato Felipe C.P. , Sernaglia Erica M. , Vinolo Marco A.R. , Rodrigues Hosana G. 
Published: November 2019

Abstract
There is no consensus on the effects of omega-3 (ω-3) fatty acids (FA) on cutaneous repair. To solve this problem, we used 2 different approaches: (1) FAT-1 transgenic mice, capable of producing endogenous ω-3 FA; (2) wild-type (WT) mice orally supplemented with DHA-enriched fish oil. FAT-1 mice had higher systemic (serum) and local (skin tissue) ω-3 FA levels, mainly docosahexaenoic acid (DHA), in comparison with WT mice. FAT-1 mice had increased myeloperoxidase (MPO) activity and content of CXCL-1 and CXCL-2, and reduced IL-10 in the skin wound tissue three days after the wound induction. Inflammation was maintained by an elevated TNF-α concentration and presence of inflammatory cells and edema. Neutrophils and macrophages, isolated from FAT-1 mice, also produced increased TNF-α and reduced IL-10 levels. In these mice, the wound closure was delayed, with a wound area 6-fold bigger in relation with WT group, on the last day of analysis (14 days post-wounding). This was associated with poor orientation of collagen fibers and structural aspects in repaired tissue. Similarly, DHA group had a delay during late inflammatory phase. This group had increased TNF-α content and CD45+F4/80+ cells at the third day after skin wounding and increased concentrations of important metabolites derived from ω-3, like 18-HEPE, and reduced concentrations of those from ω-6 FA. In conclusion, elevated DHA content, achieved in both FAT-1 and DHA groups, slowed inflammation resolution and impaired the quality of healed skin tissue.
Music Participation Among School-Aged Children Who Are Hard of Hearing
Authors: Jorgensen Erik J. , Walker Elizabeth A. 
Published: November 2019

Purpose
Music is an important part of life for many people. Furthermore, music training has been shown to improve a variety of cognitive functions among children and adults. However, little research exists on how children who are hard of hearing (HH) perceive or participate in music. In particular, it is unknown whether hearing loss limits participation in music activities among school-aged children with mild-to-severe hearing loss. The purpose of this study was to determine whether hearing loss limits participation among children who are HH compared to children with normal hearing (NH).

Method
Participants were parents of 2 cohorts of children finishing 5th grade (approximately 11 years old). Parents were asked to complete a survey (online or paper) regarding the role of music in their child's life. A total of 88 surveys were completed (67 from parents of children who are HH and 21 from parents of children with NH, with an overall response rate of 74%).

Results
Hearing loss did not limit music participation among children. Children who are HH listened to recorded music, attended live concerts, and practiced an instrument at the same rates as children with NH. Listening to recorded and live music, practicing an instrument, and playing in an ensemble were equally as important to children who are HH as children with NH. Children who are HH were significantly more likely to regularly play in an ensemble than children with NH. Parent participation in music significantly influenced music participation for children who are HH but not children with NH. Descriptive data about music genres, instruments, and ensembles are also presented.

Conclusions
Children who are HH participate in music at the same or greater rates as children with NH. Parent participation in music may be particularly important for children who are HH. In light of this, music listening should be a consideration when fitting children with hearing aids.
Detection of spectrum hole from n ‐number of primary users using machine learning algorithms
Authors: Venkateshkumar Udayamoorthy , Ramakrishnan Srinivansan 
Published: November 2019

A method for detecting spectrum holes based on the n ‐number of primary users (PU's) in a cognitive radio environment, using a cooperative spectrum sensing model is proposed in this study. The fusion centre, senses the n ‐number of PUs. When the number of PUs is >200, the probability of detection decreases, while the probability of a false alarm increases. The authors use the random forest (RF) algorithm to classify a customised dataset of 600 training samples. Further, they compare the RF algorithm and the k ‐means clustering algorithm, using test datasets with a minimum of ten PUs and a maximum of 500 PUs. Five different signal features are considered as the attributes in the proposed model. The maximum probability of detection is achieved using the k ‐means clustering algorithm in the case of 200 PUs and is 99.17%, while the false alarm probability is 0.8%. The receiver operating characteristic curves indicated that probability of detecting a spectrum hole in the case of the dataset with 500 PUs is 97.67% with the signal to noise ratio ranging from 10 to −12 dB. The accuracy can be increased if the number of clusters formed is increased, depending on the number of test samples.
Polar flux imbalance at the sunspot cycle minimum governs hemispheric asymmetry in the following cycle
Authors: Bhowmik Prantika 
Published: November 2019

Aims.Hemispheric irregularities of solar magnetic activity is a well-observed phenomenon, the origin of which has been studied through numerical simulations and data analysis techniques. In this work we explore possible causes generating north-south asymmetry in the reversal timing and amplitude of the polar field during cycle minimum. Additionally, we investigate how hemispheric asymmetry is translated from cycle to cycle.Methods.We pursued a three-step approach. Firstly, we explored the asymmetry present in the observed polar flux and sunspot area by analysing observational data of the last 110 years. Secondly, we investigated the contribution from various factors involved in the Babcock–Leighton mechanism to the evolution and generation of polar flux by performing numerical simulations with a surface flux transport model and synthetic sunspot input profiles. Thirdly, translation of hemispheric asymmetry in the following cycle was estimated by assimilating simulation-generated surface magnetic field maps at cycle minimum in a dynamo simulation. Finally, we assessed our understanding of hemispheric asymmetry in the context of observations by performing additional observational data-driven simulations.Results.Analysis of observational data shows a profound connection between the hemispheric asymmetry in the polar flux at cycle minimum and the total hemispheric activity during the following cycle. We find that the randomness associated with the tilt angle of sunspots is the most crucial element among diverse components of the Babcock–Leighton mechanism in resulting hemispheric irregularities in the evolution of polar field. Our analyses with dynamo simulations indicate that an asymmetric poloidal field at the solar minimum can introduce significant north-south asymmetry in the amplitude and timing of peak activity during the following cycle. While observational data-driven simulations reproduce salient features of the observed asymmetry in the solar cycles during the last 100 years, we speculate that fluctuations in the mean-fieldα-effect and meridional circulation can have finite contributions in this regard.