Item response theory (IRT) models are often compared with respect to predictive performance to determine the dimensionality of rating scale data. However, such model comparisons could be biased ...toward nested-dimensionality IRT models (e.g., the bifactor model) when comparing those models with non-nested-dimensionality IRT models (e.g., a unidimensional or a between-item-dimensionality model). The reason is that, compared with non-nested-dimensionality models, nested-dimensionality models could have a greater propensity to fit data that do not represent a specific dimensional structure. However, it is unclear as to what degree model comparison results are biased toward nested-dimensionality IRT models when the data represent specific dimensional structures and when Bayesian estimation and model comparison indices are used. We conducted a simulation study to add clarity to this issue. We examined the accuracy of four Bayesian predictive performance indices at differentiating among non-nested- and nested-dimensionality IRT models. The deviance information criterion (DIC), a commonly used index to compare Bayesian models, was extremely biased toward nested-dimensionality IRT models, favoring them even when non-nested-dimensionality models were the correct models. The Pareto-smoothed importance sampling approximation of the leave-one-out cross-validation was the least biased, with the Watanabe information criterion and the log-predicted marginal likelihood closely following. The findings demonstrate that nested-dimensionality IRT models are not automatically favored when the data represent specific dimensional structures as long as an appropriate predictive performance index is used.
Recent explosive advances in next-generation sequencing technology and computational approaches to massive data enable us to analyze a number of cancer genome profiles by whole-genome sequencing ...(WGS). To explore cancer genomic alterations and their diversity comprehensively, global and local cancer genome-sequencing projects, including ICGC and TCGA, have been analyzing many types of cancer genomes mainly by exome sequencing. However, there is limited information on somatic mutations in non-coding regions including untranslated regions, introns, regulatory elements and non-coding RNAs, and rearrangements, sometimes producing fusion genes, and pathogen detection in cancer genomes remain widely unexplored. WGS approaches can detect these unexplored mutations, as well as coding mutations and somatic copy number alterations, and help us to better understand the whole landscape of cancer genomes and elucidate functions of these unexplored genomic regions. Analysis of cancer genomes using the present WGS platforms is still primitive and there are substantial improvements to be made in sequencing technologies, informatics and computer resources. Taking account of the extreme diversity of cancer genomes and phenotype, it is also required to analyze much more WGS data and integrate these with multi-omics data, functional data and clinical-pathological data in a large number of sample sets to interpret them more fully and efficiently.
Summary
Background Extramammary Paget’s disease (EMPD) is a rare cutaneous carcinoma usually presenting as a genital erythematous lesion in the elderly. Although most EMPD tumours are in situ, ...invasive EMPD has a poor prognosis.
Objective To evaluate the clinical and pathological features of EMPD and determine prognostic factors for survival.
Methods The medical records of 76 patients with EMPD were retrospectively reviewed.
Results Of the 66 patients who underwent curative surgical excision, five (8%) developed local recurrence, but surgical margin (≤ 2 cm or > 2 cm) was not correlated with local recurrence. Thirteen of the 76 patients (17%) developed systemic metastases and 10 of these died of disease. On univariate analysis, the presence of nodules in the primary tumour, clinical lymph node swelling, elevated serum carcinoembryonic antigen (CEA) levels, tumour invasion level and lymph node metastasis were significant prognostic factors. On multivariate analysis, invasion level and elevated serum CEA were the only factors that were significantly associated with reduced survival.
Conclusions Invasion level and lymph node metastasis are important prognostic factors in EMPD. In patients with in situ tumour, local tumour control is the major aim of treatment; however, wide surgical margins are not associated with a lower risk of local recurrence.
Although vital pulp therapy should be performed by promoting the wound-healing capacity of dental pulp, existing pulp-capping materials were not developed with a focus on the pulpal repair process. ...In previous investigations of wound healing in dental pulp, we found that organic dentin matrix components (DMCs) were degraded by matrix metalloproteinase-20, and DMC degradation products containing protein S100A7 (S100A7) and protein S100A8 (S100A8) promoted the pulpal wound-healing process. However, the direct use of recombinant proteins as pulp-capping materials may cause clinical problems or lead to high medical costs. Thus, we hypothesized that functional peptides derived from recombinant proteins could solve the problems associated with direct use of such proteins. In this study, we identified functional peptides derived from the protein S100 family and investigated their effects on dental pulp tissue. We first performed amino acid sequence alignments of protein S100 family members from several mammalian sources, then identified candidate peptides. Next, we used a peptide array method that involved human dental pulp stem cells (hDPSCs) to evaluate the mineralization-inducing ability of each peptide. Our results supported the selection of 4 candidate functional peptides derived from proteins S100A8 and S100A9. Direct pulp-capping experiments in a rat model demonstrated that 1 S100A8-derived peptide induced greater tertiary dentin formation compared with the other peptides. To investigate the mechanism underlying this induction effect, we performed liquid chromatography–tandem mass spectrometry analysis using hDPSCs and the S100A8-derived peptide; the results suggested that this peptide promotes tertiary dentin formation by inhibiting inflammatory responses. In addition, this peptide was located in a hairpin region on the surface of S100A8 and could function by direct interaction with other molecules. In summary, this study demonstrated that a S100A8-derived functional peptide promoted wound healing in dental pulp; our findings provide insights for the development of next-generation biological vital pulp therapies.
We present solar quiet (Sq) variation of the horizontal (H) magnetic field intensity deduced from Magnetic Data Acquisition System (MAGDAS) records over Africa during an unusual strong and prolonged ...2009 sudden stratospheric warming (SSW) event. A reduction in the SqH magnitude that enveloped the geomagnetic latitudes between 21.13°N (Fayum FYM) in Egypt and 39.51°S (Durban DRB) in South Africa was observed, while the stratospheric polar temperature was increasing and got strengthened when the stratospheric temperature reached its maximum. Another novel feature associated with the hemispheric reduction is the reversal in the north‐south asymmetry of the SqH, which is indicative of higher SqH magnitude in the Northern Hemisphere compared to the Southern Hemisphere during SSW peak phase. The reversal of the equatorial electrojet (EEJ) or the counter electrojet (CEJ) was observed after the polar stratospheric temperature reached its maximum. The effect of additional currents associated with CEJ was observed in the Southern Hemisphere at middle latitude. Similar changes were observed in the EEJ at the South America, Pacific Ocean, and Central Asia sectors. The effect of the SSW is largest in the South American sector and smallest in the Central Asian sector.
Key Points
The closer a station to the dip equator, the more intense the S_qH magnitude when there is no SSW
Their is possibility of reinjection of energy in the jet as its flows eastward
Reduction of upward propagating tides from the middle atmosphere
A Pc5 wave is observed by the Exploration of energization and Radiation in Geospace Arase satellite in the inner magnetosphere (L ~5.4–6.1) near postmidnight (L‐magnetic local time ~1.8–2.5 hr) ...during the storm recovery phase on 27 March 2017. Its azimuthal wave number (m‐number) is estimated using two independent methods with satellites and ground observations to be −8 to −15. The direct measurement of the m‐number enables us to calculate the resonance energy. The flux oscillations of H+ and O+ ions at ≥ 56.3 keV are caused by drift resonance and those of O+ ions at ≤ 18.6 keV by bounce resonance. Resonances of O+ ions at multiple energies are simultaneously observed for the first time. The enhancement of the O+/H+ flux ratio at ≤ 18.6 keV indicates selective acceleration of O+ ions through bounce resonance.
Plain Language Summary
Geomagnetic pulsations are magnetic fluctuations excited by solar wind or plasma instabilities in the magnetosphere. Pc5 waves are continuous geomagnetic pulsations with a period of 150–600 s. A Pc5 wave was observed in the inner magnetosphere during a magnetic storm on 27 March 2017. It propagated westward with a wave number of 8 to 15 and resonated with charged particles, resulting in oscillations of the H+ and O+ ion fluxes at ≥ 56.3 keV and the O+ ion fluxes at ≤ 18.6 keV. Resonances of O+ ions at multiple energies are simultaneously observed for the first time. At the same time, the O+/H+ flux ratio at ≤ 18.6 keV enhanced corresponding to the O+ ion flux oscillations, which indicates selective acceleration of O+ ions through resonances.
Key Points
A large‐amplitude Pc5 wave is observed by Arase and MMS1 in the postmidnight region at L > 5.4 during the storm recovery phase
We estimate the m‐number of the Pc5 wave to be −8 to −15 by using two independent methods with satellites and ground observations
We simultaneously observe the drift resonance for H+ and O+ ions at ≥ 56.3 keV and bounce resonance for O+ ions at ≤ 18.6 keV
Storm‐time region‐2 field‐aligned currents (R2 FACs) are believed to be connected between the ring current region and the ionosphere, but this connection has not been clarified by simultaneous ...in situ observations. We confirmed the connection of upward R2 FACs during 16 July and 18 June 2017 storm events using coordinated magnetic observations by the Arase satellite in medium‐Earth orbit and the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). The upward FACs were determined by drastic changes in the azimuthal magnetic field at Arase in the off‐equatorial (3‐ to 4‐RE radial distance and 1–2 RE above the magnetic equator) postmidnight inner magnetosphere. The magnetic latitude of the FAC observed by Arase projected onto the ionosphere was consistent with that of the ionospheric FAC observed by the AMPERE. Using the conservation of the ratio between the current density and the total magnetic field along the field line, we showed that the current between Arase and AMPERE was almost conserved, meaning that a large portion of the R2 FAC was generated in the low‐latitude inner magnetosphere. We also calculated the plasma pressures of H+ and O+ ions and pressure‐driven currents to examine their relationship for the first event. The O+ pressure contributed significantly to the inner part of the total azimuthal current. The peaks of combined pressure of H+ and O+, and pressure‐driven currents were located inside and outside the FAC, respectively. A simple model calculation indicated that this spatial relationship is controlled by the day‐night asymmetry of magnetic field.
Key Points
Connection of FACs in the inner magnetosphere and in the ionosphere was quantitatively confirmed by Arase and AMPERE observations
We present simultaneous in situ observations of storm‐time region‐2 FACs and the ring current derived from plasma pressures
The region‐2 FAC was located at the inner part of the ring current that was significantly contributed to by O+ ions
In recent years, it has been clarified from previous studies that plasma bubbles and equatorial electrojets (EEJs) are related. In general, EEJs are calculated by subtracting the magnetic field H ...component of the magnetic equator from that at low latitude. However, in this study, EE-index data at Langkawi (magnetic equator), which includes all local current systems, were used for the analysis during the period from January 1, 2011, to November 8, 2014. By using the EE-index, it was found that plasma bubbles tend to occur for larger EEJ strengths. This result differs from the previous studies. In addition, if an equatorial counter electrojet (CEJ) occurs, it is understood that plasma bubbles will rarely occur due to the westward current; however, we found that when the lunar tidal effect is strong, plasma bubbles can occur even in conjunction with CEJs. Finally, we want to find the relationship between plasma bubbles and ionospheric current to predict them.
We report the electron flux modulations without corresponding magnetic fluctuations from unique multipoint satellite observations of the Arase (Exploration of Energization and Radiation in Geospace) ...and the Van Allen Probe (Radiation Belt Storm Probe RBSP)‐B satellites. On 30 March 2017, both Arase and RBSP‐B observed periodic fluctuations in the relativistic electron flux with energies ranging from 500 keV to 2 MeV when they were located near the magnetic equator in the morning and dusk local time sectors, respectively. Arase did not observe Pc5 pulsations, while they were observed by RBSP‐B. The clear dispersion signature of the relativistic electron fluctuations observed by Arase indicates that the source region is limited to the postnoon to the dusk sector. This is confirmed by RBSP‐B and ground‐magnetometer observations, where Pc5 pulsations are observed to drift‐resonate with relativistic electrons on the duskside. Thus, Arase observed the drift‐resonance signatures “remotely,” whereas RBSP‐B observed them “locally.”
Plain Language Summary
Magnetohydrodynamic waves in the outer radiation belt with periods of ~150–250 s occasionally cause the acceleration of energetic electrons drifting eastward around the Earth. We examined the longitudinal distributions of the interaction region in which magnetohydrodynamic waves with periods of ~150–250 s interacted with energetic electrons on 30 March 2017, using simultaneously observed data by multisatellite observations from the Arase and the Radiation Belt Storm Probe (RBSP)‐B satellites. Both satellites observed radiation belts at different local times but at almost the same Earth radii. The Arase satellite located in the dawn sector observed energetic electron flux modulations that had clear energy dispersion signatures, while magnetohydrodynamic waves with the same period were not identified. However, the RBSP‐B located in the dusk sector simultaneously observed magnetohydrodynamic waves and the energetic electron modulations with the characteristics of the interaction. This multipoint measurement indicates that the interaction region is limited from the postnoon to the dusk sector.
Key Points
Arase observed flux modulations of relativistic electrons at 04 MLT without variations in the ambient magnetic and electric fields
Time‐of‐flight analysis from the energy dispersion of relativistic electrons identified the drift‐resonant region to be 14–18 MLT
The interactions between Pc5 waves and relativistic electrons occurred at a limited local time even though the estimated m number is small
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