bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long-term outcomes of ossiculoplasty using bone cement
Authors: Demir B , Binnetoglu A , Sahin A , Derinsu U , Batman Ç 
Published: July 2019

AbstractObjectiveThis study aimed to evaluate the long-term results of ossiculoplasty using bone cement.MethodForty patients (24 females and 16 males; mean age: 34.1 ± 11.8 years; range, 9–54 years) with chronic otitis media with perforation but without cholesteatoma who had undergone incudostapedial rebridging ossiculoplasty using bone cement were evaluated retrospectively. Pre-operative and post-operative audiograms were evaluated. Bone conduction, air conduction and air–bone gaps were calculated according to international guidelines.ResultsThere was a mean reduction in pre-operative and post-operative air conduction (12.30 ± 11.98 dB), and this result was significant (p = 0.0001). There was a mean reduction in pre-operative and post-operative bone conduction (4.30 ± 6.69 dB), and this result was significant (p < 0.0001). The pre-operative air–bone gap was 27.65 dB and decreased to 19.65 dB during follow-up (p = 0.0001). No adverse reactions or complications were observed.ConclusionBone cement is reliable for the repair of incudostapedial-joint defects.
Modeling Ocean Eddies on Antarctica's Cold Water Continental Shelves and Their Effects on Ice Shelf Basal Melting
Authors: Mack Stefanie L. , Dinniman Michael S. , Klinck John M. , McGillicuddy Dennis J. , Padman Laurence 
Published: July 2019

AbstractChanges in the rate of ocean‐driven basal melting of Antarctica's ice shelves can alter the rate at which the grounded ice sheet loses mass and contributes to sea level change. Melt rates depend on the inflow of ocean heat, which occurs through steady circulation and eddy fluxes. Previous studies have demonstrated the importance of eddy fluxes for ice shelves affected by relatively warm intrusions of Circumpolar Deep Water. However, ice shelves on cold water continental shelves primarily melt from dense shelf water near the grounding line and from light surface water at the ice shelf front. Eddy effects on basal melt of these ice shelves have not been studied. We investigate where and when a regional ocean model of the Ross Sea resolves eddies and determine the effect of eddy processes on basal melt. The size of the eddies formed depends on water column stratification and latitude. We use simulations at horizontal grid resolutions of 5 and 1.5 km and, in the 1.5‐km model, vary the degree of topography smoothing. The higher‐resolution models generate about 2–2.5 times as many eddies as the low‐resolution model. In all simulations, eddies cross the ice shelf front in both directions. However, there is no significant change in basal melt between low‐ and high‐resolution simulations. We conclude that higher‐resolution models (<1 km) are required to better represent eddies in the Ross Sea but hypothesize that basal melt of the Ross Ice Shelf is relatively insensitive to our ability to fully resolve the eddy field.
The Challenge of Machine Learning in Space Weather: Nowcasting and Forecasting
Authors: Camporeale E. 
Published: July 2019

AbstractThe numerous recent breakthroughs in machine learning make imperative to carefully ponder how the scientific community can benefit from a technology that, although not necessarily new, is today living its golden age. This Grand Challenge review paper is focused on the present and future role of machine learning in Space Weather. The purpose is twofold. On one hand, we will discuss previous works that use machine learning for Space Weather forecasting, focusing in particular on the few areas that have seen most activity: the forecasting of geomagnetic indices, of relativistic electrons at geosynchronous orbits, of solar flares occurrence, of coronal mass ejection propagation time, and of solar wind speed. On the other hand, this paper serves as a gentle introduction to the field of machine learning tailored to the Space Weather community and as a pointer to a number of open challenges that we believe the community should undertake in the next decade. The recurring themes throughout the review are the need to shift our forecasting paradigm to a probabilistic approach focused on the reliable assessment of uncertainties, and the combination of physics‐based and machine learning approaches, known as gray box.
Sediments in Agricultural Reservoirs Act as Sinks and Sources for Nutrients over Various Timescales
Authors: Shaughnessy A.R. , Sloan J.J. , Corcoran M.J. , Hasenmueller E.A. 
Published: July 2019

AbstractReservoirs along rivers have the potential to act as nutrient sinks (e.g., denitrification and sedimentation) or sources (e.g., decomposition and redox changes), potentially reducing or enhancing nutrient loads downstream. This study investigated the spatial and temporal variability of water and lakebed sediment chemistry for an agricultural reservoir, Carlyle Lake (Illinois, U.S.), to assess the role of sediments as nutrient sinks or sources. Samples were collected across the reservoir over a 2‐year period. We measured N‐ and P‐species in water at the sediment‐water interface, in sediment porewaters, and loosely bound to sediment exchange sites. Total N, total P, total C, organic matter, Fe, Mn, and grain size were measured in bulk sediments. We observed a strong gradient in sedimentary total N, total P, total C, organic matter, and metals along the reservoir, with the lowest concentrations at the river mouth and the highest concentrations near the dam. Additionally, we did a long‐term nutrient mass balance using historical water quality data for streams entering and exiting the reservoir and the reservoir itself. Mass balance calculations showed that Carlyle Lake, on average, removed 2,738 Mg N/year and released 121 Mg P/year over the multidecadal observation period. While N was consistently removed from the system over time, P was initially stored in, but later released from, the reservoir. The subsequent release of legacy P from the reservoir led to higher outgoing, compared with incoming, P loads. Thus, reservoirs in intensively managed landscapes can act as sinks for N but sources for P over decadal timescales.
Anomalous Trapping of Low Pitch Angle Electrons by Coherent Whistler Mode Waves
Authors: Kitahara M. , Katoh Y. 
Published: July 2019

AbstractChorus emissions composed of coherent whistler mode waves are responsible for pitch angle scattering of energetic electrons. This scattering is closely related to energetic electron precipitation into the atmosphere, contributing to pulsating auroras. Conventionally, energetic electrons are considered to satisfy the cyclotron resonance condition over the energy range of a few to tens of kiloelectron volts and are scattered toward the loss cone by waves. However, previous simulation studies indicate that low pitch angle electrons tend to be scattered away from the loss cone by coherent whistler mode waves. We examine the mechanism of anomalous trapping at low pitch angles, deriving a particle equation with low pitch angle assumptions. An additional term that is conventionally neglected represents the Lorentz force caused by the wave magnetic field and the parallel particle velocity. Therefore, due to the large v‖×Bw Lorentz force, low pitch angle electrons satisfying the cyclotron resonant condition are scattered away from the loss cone and effectively trapped by waves. We perform test particle simulations in a one‐dimensional dipole magnetic field with a whistler mode wave model and reproduce the anomalous trapping of electrons. The simulation results show that the majority of electrons at high and moderate pitch angles are scattered toward low pitch angle regions while low pitch angle electrons are strongly scattered toward high pitch angle regions. Consequently, a coherent chorus element produces a bump in the electron pitch angle distribution.
Separation and Quantification of Ionospheric Convection Sources: 2. The Dipole Tilt Angle Influence on Reverse Convection Cells During Northward IMF
Authors: Reistad J. P. , Laundal K. M. , Østgaard N. , Ohma A. , Thomas E. G. , Haaland S. , Oksavik K. , Milan S. E. 
Published: July 2019

AbstractThis paper investigates the influence of Earth's dipole tilt angle on the reverse convection cells (sometimes referred to as lobe cells) in the Northern Hemisphere ionosphere during northward IMF, which we relate to high‐latitude reconnection. Super Dual Auroral Radar Network plasma drift observations in 2010–2016 are used to quantify the ionospheric convection. A novel technique based on Spherical Elementary Convection Systems (SECS) that was presented in our companion paper (Reistad et al., 2019, https://doi.org/10.1029/2019JA026634) is used to isolate and quantify the reverse convection cells. We find that the dipole tilt angle has a linear influence on the reverse cell potential. In the Northern Hemisphere the reverse cell potential is typically two times higher in summer than in winter. This change is interpreted as the change in interplanetary magnetic field‐lobe reconnection rate due to the orientation of the dipole tilt. Hence, the dipole tilt influence on reverse ionospheric convection can be a significant modification of the more known influence from vswBz. These results could be adopted by the scientific community as key input parameters for lobe reconnection coupling functions.
On the Contribution of Dipolarizing Flux Bundles to the Substorm Current Wedge and to Flux and Energy Transport
Authors: Birn J. , Liu J. , Runov A. , Kepko L. , Angelopoulos V. 
Published: July 2019

AbstractBursty bulk flows and dipolarizing flux bundles within them play an important role in the transport of mass, energy, and magnetic flux in the magnetotail. On the basis of an magnetohydrodynamic simulation of magnetotail reconnection and dipolarization, we investigate the contribution of individual bursts and flux transport events to the buildup of the substorm current wedge, as well as to the earthward transport of magnetic flux and energy. Individual events, defined by increased flow speed (flow bursts), increased cross‐tail electric field, or increased (or increasing) magnetic field Bz, are found to be closely related but not identical. Multiple individual magnetic flux transport events collectively contribute to tailward and azimuthal expansion of dipolarization in the inner tail and to an increase of total field‐aligned currents toward or away from the ionosphere. In contrast, the current closure across midnight, estimated from the surface currents at the inner (earthward) boundary of the simulation box, was found to remain only a fraction (∼10% or 0.2 MA) of the total Region 1 current into to ionosphere. The simulation showed dipolarization everywhere earthward of the near‐Earth x‐line, amounting to ∼2.3 ×108 Wb, commensurate with substorm estimates. This can appear at a satellite in various ways, through either classical earthward transport and pileup (outward moving accumulation) or lateral (azimuthal) or tailward (vortical or recoiled) convective motion of dipolarized flux tubes, or a combination of these.
Pressure Gradients Driving Ion Transport in the Topside Martian Atmosphere
Authors: Hamil O. , Cravens T. E. , Rahmati A. , Connerney J. E. P. , Andersson L. 
Published: July 2019

AbstractMagnetic and thermal pressure gradient forces drive plasma flow in the topside ionosphere of Mars. Some of this flow can contribute to ion loss from the planet and thus affect atmospheric evolution. MAVEN measurements of the magnetic field, electron density, and electron temperature, taken over a 3‐year time period, are used to obtain averaged magnetic and thermal pressures in the topside ionosphere versus altitude, solar zenith angle, and latitude. Magnetic pressures are several times greater than thermal pressures for altitudes greater than about 300 km; that is, the plasma beta is less than one. The total pressure increases with altitude in the ionosphere and decreases with increasing solar zenith angle. Using these pressure patterns in the dayside ionosphere to estimate the pressure gradient force in the fluid momentum equation, we estimate horizontal day‐to‐night plasma flow speeds of a few kilometers per second near 400 km.
On the Momentum Transfer From Polar to Equatorial Ionosphere
Authors: Tu Jiannan , Song Paul 
Published: July 2019

AbstractDuring space weather events, a large amount of energy and momentum from the solar wind inputs into the ionosphere‐thermosphere. A critical question is that if the solar wind‐magnetosphere interaction drives only the open field region in the polar caps, how the solar wind energy and momentum are transmitted to the low latitude and equatorial ionosphere. This important issue has been studied over decades and is still poorly understood, impeding space weather forecasting ability. Here we use our newly developed 2.5‐D ionosphere‐thermosphere simulation model that self‐consistently solves the density, velocity, and temperature for electrons, multiple ion and neutral species, and electromagnetic fields to study this challenging problem. The focus of the present study is on the prompt response of the ionosphere to a convection disturbance from the polar magnetosphere. The longer time scale responses caused by the neutral winds from the polar caps will be the topic of future studies. We show that the momentum is transferred from polar to equatorial ionosphere predominately by fast magnetosonic waves, and propagation of perturbations from the source region experiences delay, damping, and substantial reflection, and the ionosphere/thermosphere behaves like a low‐band‐pass filter. The finding from this study sheds new insight onto coupling processes within the magnetosphere‐ionosphere system.
Overexpression of Nanog in amniotic fluid–derived mesenchymal stem cells accelerates dermal papilla cell activity and promotes hair follicle regeneration
Authors: Park Junghyun , Jun Eun Kyoung , Son Daryeon , Hong Wonjun , Jang Jihoon , Yun Wonjin , Yoon Byung Sun , Song Gwonhwa , Kim In Yong , You Seungkwon 
Published: July 2019

AbstractAlopecia, one of the most common chronic diseases, can seriously affect a patient’s psychosocial life. Dermal papilla (DP) cells serve as essential signaling centers in the regulation of hair growth and regeneration and are associated with crosstalk between autocrine/paracrine factors and the surrounding environment. We previously demonstrated that amniotic fluid–derived mesenchymal stem cell–conditioned medium (AF-MSC-CM) accelerates hair regeneration and growth. The present study describes the effects of overexpression of a reprogramming factor, Nanog, on MSC properties, the paracrine effects on DP cells, and in vivo hair regrowth. First, we examined the in vitro proliferation and lifespan of AF-MSCs overexpressing reprogramming factors, including Oct4, Nanog, and Lin28, alone or in combination. Among these factors, Nanog was identified as a key factor in maintaining the self-renewal capability of AF-MSCs by delaying cellular senescence, increasing the endogenous expression of Oct4 and Sox2, and preserving stemness. Next, we evaluated the paracrine effects of AF-MSCs overexpressing Nanog (AF-N-MSCs) by monitoring secretory molecules related to hair regeneration and growth (IGF, PDGF, bFGF, and Wnt7a) and proliferation of DP cells. In vivo studies revealed that CM derived from AF-N-MSCs (AF-N-CM) accelerated the telogen-to-anagen transition in hair follicles (HFs) and increased HF density. The expression of DP and HF stem cell markers and genes related to hair induction were higher in AF-N-CM than in CM from AF-MSCs (AF-CM). This study suggests that the secretome from autologous MSCs overexpressing Nanog could be an excellent candidate as a powerful anagen inducer and hair growth stimulator for the treatment of alopecia.
Reduced P53 levels ameliorate neuromuscular junction loss without affecting motor neuron pathology in a mouse model of spinal muscular atrophy
Authors: Courtney Natalie L. , Mole Alannah J. , Thomson Alison K. , Murray Lyndsay M. 
Published: July 2019

AbstractSpinal Muscular Atrophy (SMA) is a childhood motor neuron disease caused by mutations or deletions within the SMN1 gene. At endstages of disease there is profound loss of motor neurons, loss of axons within ventral roots and defects at the neuromuscular junctions (NMJ), as evidenced by pathological features such as pre-synaptic loss and swelling and post-synaptic shrinkage. Although these motor unit defects have been widely described, the time course and interdependancy of these aspects of motor unit degeneration are unclear. Recent reports have also revealed an early upregulation of transcripts associated with the P53 signalling pathway. The relationship between the upregulation of these transcripts and pathology within the motor unit is also unclear. In this study, we exploit the prolonged disease timecourse and defined pre-symptomatic period in the Smn2B/− mouse model to perform a temporal analysis of the different elements of motor unit pathology. We demonstrate that NMJ loss occurs prior to cell body loss, and coincides with the onset of symptoms. The onset of NMJ pathology also coincides with an increase in P53-related transcripts at the cell body. Finally, using a tamoxifen inducible P53 knockout, we demonstrate that post-natal reduction in P53 levels can reduce NMJ loss, but does not affect other aspects of NMJ pathology, motor neuron loss or the phenotype of the Smn2B/− mouse model. Together this work provides a detailed temporal description of pathology within motor units of an SMA mouse model, and demonstrates that NMJ loss is a P53-dependant process. This work supports the role for P53 as an effector of synaptic and axonal degeneration in a die-back neuropathy.
Poly (rC) binding protein 2 interacts with VP0 and increases the replication of the foot-and-mouth disease virus
Authors: Li Dan , Zhang Jing , Yang Wenping , He Yanchun , Ru Yi , Fu Shaozu , Li Lulu , Liu Xiangtao , Zheng Haixue 
Published: July 2019

AbstractFoot-and-mouth disease virus (FMDV) causes a highly contagious and debilitating disease in cloven-hoofed animals, which leads to devastating economic consequences. Previous studies have reported that some FMDV proteins can interact with host proteins to affect FMDV replication. However, the influence of the interactions between FMDV VP0 protein and its partners on FMDV replication remains unknown. In this study, we found that the overexpression of poly (rC) binding protein 2 (PCBP2) promoted FMDV replication, whereas the knockdown of PCBP2 suppressed FMDV replication. Furthermore, PCBP2 can interact with FMDV VP0 protein to promote the degradation of VISA via the apoptotic pathway. Further studies demonstrated that FMDV VP0 protein enhanced the formation of the PCBP2-VISA complex. Ultimately, we found that the degradation of VISA was weaker in PCBP2-knockdown and FMDV VP0-overexpressing cells, or FMDV VP0-knockdown cells than in the control cells. Summarily, our data revealed that the interaction between PCBP2 and VP0 could promote FMDV replication via the apoptotic pathway.
Mechanical impact of epithelial−mesenchymal transition on epithelial morphogenesis in Drosophila
Authors: Gracia Mélanie , Theis Sophie , Proag Amsha , Gay Guillaume , Benassayag Corinne , Suzanne Magali 
Published: July 2019

AbstractEpithelial−mesenchymal transition (EMT) is an essential process both in physiological and pathological contexts. Intriguingly, EMT is often associated with tissue invagination during development; however, the impact of EMT on tissue remodeling remain unexplored. Here, we show that at the initiation of the EMT process, cells produce an apico-basal force, orthogonal to the surface of the epithelium, that constitutes an important driving force for tissue invagination in Drosophila. When EMT is ectopically induced, cells starting their delamination generate an orthogonal force and induce ectopic folding. Similarly, during mesoderm invagination, cells undergoing EMT generate an apico-basal force through the formation of apico-basal structures of myosin II. Using both laser microdissection and in silico physical modelling, we show that mesoderm invagination does not proceed if apico-basal forces are impaired, indicating that they constitute driving forces in the folding process. Altogether, these data reveal the mechanical impact of EMT on morphogenesis.
Pooled clone collections by multiplexed CRISPR-Cas12a-assisted gene tagging in yeast
Authors: Buchmuller Benjamin C. , Herbst Konrad , Meurer Matthias , Kirrmaier Daniel , Sass Ehud , Levy Emmanuel D. , Knop Michael 
Published: July 2019

AbstractClone collections of modified strains (“libraries”) are a major resource for systematic studies with the yeast Saccharomyces cerevisiae. Construction of such libraries is time-consuming, costly and confined to the genetic background of a specific yeast strain. To overcome these limitations, we present CRISPR-Cas12a (Cpf1)-assisted tag library engineering (CASTLING) for multiplexed strain construction. CASTLING uses microarray-synthesized oligonucleotide pools and in vitro recombineering to program the genomic insertion of long DNA constructs via homologous recombination. One simple transformation yields pooled libraries with >90% of correctly tagged clones. Up to several hundred genes can be tagged in a single step and, on a genomic scale, approximately half of all genes are tagged with only ~10-fold oversampling. We report several parameters that affect tagging success and provide a quantitative targeted next-generation sequencing method to analyze such pooled collections. Thus, CASTLING unlocks avenues for increasing throughput in functional genomics and cell biology research.
Non-aromatic annulene-based aggregation-induced emission system via aromaticity reversal process
Authors: Zhao Zheng , Zheng Xiaoyan , Du Lili , Xiong Yu , He Wei , Gao Xiuxiu , Li Chunli , Liu Yingjie , Xu Bin , Zhang Jing , Song Fengyan , Yu Ying , Zhao Xueqian , Cai Yuanjing , He Xuewen , Kwok Ryan T. K. , Lam Jacky W. Y. , Huang Xuhui , Lee Phillips David , Wang Hua , Tang Ben Zhong 
Published: July 2019

AbstractAggregation-induced emission (AIE) is a photophysical phenomenon correlated closely with the excited-state intramolecular motions. Although AIE has attracted increasing attention due to the significant applications in biomedical and optoelectronics, an in-depth understanding of the excited-state intramolecular motion has yet to be fully developed. Here we found the non-aromatic annulene derivative of cyclooctatetrathiophene shows typical AIE phenomenon in spite of its rotor-free structure. The underlying mechanism is investigated through photoluminescence spectra, time-resolved absorption spectra, theoretical calculations, circular dichroism as well as by pressure-dependent fluorescent spectra etc., which indicate that the aromaticity reversal from ground state to the excited state serves as a driving force for inducing the excited-state intramolecular vibration, leading to the AIE phenomenon. Therefore, aromaticity reversal is demonstrated as a reliable strategy to develop vibrational AIE systems. This work also provides a new viewpoint to understand the excited-state intramolecular motion behavior of lumiongens.