ABSTRACT We report the results of the statistical analysis of planetary signals discovered in MOA-II microlensing survey alert system events from 2007 to 2012. We determine the survey sensitivity as ...a function of planet-star mass ratio, q, and projected planet-star separation, s, in Einstein radius units. We find that the mass-ratio function is not a single power law, but has a change in slope at q ∼ 10−4, corresponding to ∼20 M⊕ for the median host-star mass of ∼0.6 . We find significant planetary signals in 23 of the 1474 alert events that are well-characterized by the MOA-II survey data alone. Data from other groups are used only to characterize planetary signals that have been identified in the MOA data alone. The distribution of mass ratios and separations of the planets found in our sample are well fit by a broken power-law model of the form for q > qbr and for q < qbr, where qbr is the mass ratio of the break. We also combine this analysis with the previous analyses of Gould et al. and Cassan et al., bringing the total sample to 30 planets. This combined analysis yields , n = −0.93 0.13, , and for qbr 1.7 × 10−4. The unbroken power-law model is disfavored with a p-value of 0.0022, which corresponds to a Bayes factor of 27 favoring the broken power-law model. These results imply that cold Neptunes are likely to be the most common type of planets beyond the snow line.
Abstract
We report discovery of the lowest mass ratio exoplanet to be found by the microlensing method in the light curve of the event OGLE 2016–BLG–1195. This planet revealed itself as a small ...deviation from a microlensing single lens profile from an examination of the survey data. The duration of the planetary signal is ∼2.5 h. The measured ratio of the planet mass to its host star is q = 4.2 ± 0.7 × 10−5. We further estimate that the lens system is likely to comprise a cold ∼3 Earth mass planet in an ∼2 au wide orbit around a 0.2 Solar mass star at an overall distance of 7.1 kpc.
MOA-2006-BLG-074 was selected as one of the most promising planetary candidates in a retrospective analysis of the MOA collaboration: its asymmetric high-magnification peak can be perfectly explained ...by a source passing across a central caustic deformed by a small planet. However, after a detailed analysis of the residuals, we have realized that a single lens and a source orbiting with a faint companion provides a more satisfactory explanation for all the observed deviations from a Paczynski curve and the only physically acceptable interpretation. Indeed the orbital motion of the source is constrained enough to allow a very good characterization of the binary source from the microlensing light curve. The case of MOA-2006-BLG-074 suggests that the so-called xallarap effect must be taken seriously in any attempts to obtain accurate planetary demographics from microlensing surveys.
We report on the analysis of a microlensing event, OGLE-2014-BLG-1722, that showed two distinct short-term anomalies. The best-fit model to the observed light curves shows that the two anomalies are ...explained with two planetary mass ratio companions to the primary lens. Although a binary-source model is also able to explain the second anomaly, it is marginally ruled out by 3.1 . The two-planet model indicates that the first anomaly was caused by planet "b" with a mass ratio of and projected separation in units of the Einstein radius, s = 0.753 0.004. The second anomaly reveals planet "c" with a mass ratio of with Δχ2 ∼ 170 compared to the single-planet model. Its separation has two degenerated solutions: the separation of planet c is s2 = 0.84 0.03 and 1.37 0.04 for the close and wide models, respectively. Unfortunately, this event does not show clear finite-source and microlensing parallax effects; thus, we estimated the physical parameters of the lens system from Bayesian analysis. This gives the masses of planets b and c as and , respectively, and they orbit a late-type star with a mass of located at from us. The projected distances between the host and planets are for planet b and and for the close and wide models of planet c. If the two-planet model is true, then this is the third multiple-planet system detected using the microlensing method and the first multiple-planet system detected in low-magnification events, which are dominant in the microlensing survey data. The occurrence rate of multiple cold gas giant systems is estimated using the two such detections and a simple extrapolation of the survey sensitivity of the 6 yr MOA microlensing survey combined with the 4 yr FUN detection efficiency. It is estimated that 6% 2% of stars host two cold giant planets.
This study aimed to determine the clinical benefit of neoadjuvant methotrexate, doxorubicin, vinblastine, and cisplatin (MVAC) in patients with muscle-invasive bladder cancer (MIBC) treated with ...radical cystectomy.
Patients with MIBC (T2-4aN0M0) were randomised to receive two cycles of neoadjuvant MVAC followed by radical cystectomy (NAC arm) or radical cystectomy alone (RC arm). The primary end point was overall survival (OS). Secondary end points were progression-free survival, surgery-related complications, adverse events during chemotherapy, proportion with no residual tumour in the cystectomy specimens, and quality of life. To detect an improvement in 5-year OS from 45% in the RC arm to 57% in the NAC arm with 80% power, 176 events were required per arm.
Patients (N = 130) were randomly assigned to the RC arm (N = 66) and the NAC arm (N = 64). The patient registration was terminated before reaching the initially planned number of patients because of slow accrual. At the second interim analysis just after the early stoppage of patient accrual, the Data and Safety Monitoring Committee recommended early publication of the results because the trial did not have enough power to draw a confirmatory conclusion. OS of the NAC arm was better than that of the RC arm, although the difference was not statistically significant hazard ratio 0.65, multiplicity adjusted 99.99% confidence interval 0.19–2.18, one-sided P = 0.07. In the NAC arm and the RC arm, 34% and 9% of the patients had pT0, respectively (P < 0.01). In subgroup analyses, OS in almost all subgroups was in favour of NAC.
This trial showed a significantly increased pT0 proportion and favourable OS of patients who received neoadjuvant MVAC. NAC with MVAC can still be considered promising as a standard treatment.
C000000093.
We present the discovery of a substellar companion to the primary host lens in the microlensing event MOA-2012-BLG-006. The companion-to-host mass ratio is 0.016, corresponding to a companion mass of ...≈8 MJup(M∗/ 0.5 M⊙). Thus, the companion is either a high-mass giant planet or a low-mass brown dwarf, depending on the mass of the primary M∗. The companion signal was separated from the peak of the primary event by a time that was as much as four times longer than the event timescale. We therefore infer a relatively large projected separation of the companion from its host of ≈10 au(M∗/ 0.5 M⊙)1 / 2 for a wide range (3–7 kpc) of host star distances from the Earth. We also challenge a previous claim of a planetary companion to the lens star in microlensing event OGLE-2002-BLG-045.
Memory T cells are well known to have a critical role for host defense in humans. However, their role in actual human cancer remains largely unknown. In this study, we tried to reveal the clinical ...importance of tumour-infiltrating CD45RO+ memory T cells in renal cell carcinoma (RCC).
We analysed 105 patients with RCC, who received radical or partial nephrectomy. Those were 65 in TNM stage I, 7 in stage II, 15 in stage III, and 18 in stage IV, respectively. CD45RO expression was evaluated by immunohistochemistry. CD4 and CD8 expressions were also systematically assessed in the same manner.
Patients with higher TNM stage or high nuclear grade were found to have higher densities of CD45RO. Furthermore, CD45RO status was positively correlated with preoperative C-reactive protein level. In prognostic analysis, CD45RO+lo patients had a significantly better prognosis than CD45RO+hi patients. There was also a significant difference between CD4+lo and CD4+hi groups, whereas no significant difference was observed in CD8 T-cell status. Finally, multivariate analysis revealed that CD45RO+ status was the independent prognostic factor for patient overall survival.
CD45RO+ memory T-cell status has a significant independent prognostic value, indicating that the adaptive immune response is functionally critical in human RCC.
We report the discovery of a microlensing planet-MOA-2016-BLG-227Lb-with a large planet/host mass ratio of q 9 × 10−3. This event was located near the K2 Campaign 9 field that was observed by a large ...number of telescopes. As a result, the event was in the microlensing survey area of a number of these telescopes, and this enabled good coverage of the planetary light-curve signal. High angular resolution adaptive optics images from the Keck telescope reveal excess flux at the position of the source above the flux of the source star, as indicated by the light-curve model. This excess flux could be due to the lens star, but it could also be due to a companion to the source or lens star, or even an unrelated star. We consider all these possibilities in a Bayesian analysis in the context of a standard Galactic model. Our analysis indicates that it is unlikely that a large fraction of the excess flux comes from the lens, unless solar-type stars are much more likely to host planets of this mass ratio than lower mass stars. We recommend that a method similar to the one developed in this paper be used for other events with high angular resolution follow-up observations when the follow-up observations are insufficient to measure the lens-source relative proper motion.
We present the result of microlensing event MOA-2016-BLG-290, which received observations from the two-wheel Kepler (K2), Spitzer, as well as ground-based observatories. A joint analysis of data from ...K2 and the ground leads to two degenerate solutions of the lens mass and distance. This degeneracy is effectively broken once the (partial) Spitzer light curve is included. Altogether, the lens is found to be an extremely low-mass star or brown dwarf ( ) located in the Galactic bulge ( kpc). MOA-2016-BLG-290 is the first microlensing event for which we have signals from three well-separated (∼1 au) locations. It demonstrates the power of two-satellite microlensing experiment in reducing the ambiguity of lens properties, as pointed out independently by S. Refsdal and A. Gould several decades ago.
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