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Follow-up of aneurysms treated with stent-assisted coil embolization has been performed using digital subtraction angiography (DSA) because in time-of-flight magnetic resonance angiography, metal artifacts from the stent often affect visualization.To confirm whether ultrashort echo time (TE) MRA may be an alternative for DSA during follow-up.Patients with unruptured aneurysms initially treated with stent-assisted coil embolization between April 2019 and March 2021 were enrolled. After 3 months of treatment, follow-up DSA and ultrashort TE MRA were performed. All images were independently reviewed by neurosurgeons to evaluate in-stent flow and rated from 1 (not visible) to 4 (excellent). Aneurysmal embolization status was assessed as complete obliteration, residual neck, or residual aneurysm. Ultrashort TE MRA findings were classified as evaluative or nonevaluative state based on the presence of metal artifacts. We investigated the types of aneurysms that were evaluative and the agreement between ultrashort TE and DSA.Overall, 89 aneurysms were examined, of which 74% (n = 66) were classified as evaluative on ultrashort TE. Significant differences were observed in size and stent type. Evaluative cases had an aneurysm size of7 mm (P = .0007) and a higher rate of Neuroform Atlas (P = .0006). The rate of agreement between ultrashort TE with evaluative state and DSA was 95%.Ultrashort TE MRA could evaluate an embolization status treated with stenting, and the findings are in excellent agreement with those of DSA. Aneurysms measuring7 mm and treated with Neuroform Atlas are evaluative on ultrashort TE, and DSA might not be necessary.

Carotid-cavernous sinus fistula (CCF) caused by a ruptured aneurysm of the persistent primitive trigeminal artery (PPTA) is rarely reported. A 69-year-old woman presented with progressive ptosis and pulsating tinnitus. Vertebral angiography under flow control of the internal carotid artery revealed CCF associated with a ruptured PPTA-trunk aneurysm, and PPTA was divided into Saltzman type 2. Endovascular treatment was performed by coil embolization of the aneurysm and parent artery occlusion of the PPTA, preserving the basilar artery (BA) side of PPTA, without complications. In the case of ruptured aneurysms originating from the Saltzman type 2 PPTA trunk, parent artery occlusion of the PPTA might be a treatment option and preservation of the BA side of PPTA is necessary to avoid ischemic complication of pons.

The KOTO experiment at the J-PARC 30GeV Main Ring aims to study the rare decay K L → π 0 ν ν ¯ . This decay directly breaks the CP symmetry and is highly suppressed in the Standard Model (SM). In addition, the theoretical uncertainties on the decay is only a few percent. Those features make this decay one of the best probes to search for new physics beyond the SM. We had found new background sources from the analysis of the 2016-2018 data set. Thus, we took measures against the new background events. In this paper, we briefly introduce the results of the 2016-2018 data analysis. We thus report the new detectors and analysis tools that we introduced to reduce the new background events and also the other types of background events. Finally, we report the status of the 2021 data analysis.

The KOTO experiment at the J-PARC 30GeV Main Ring aims to observe the $K^{0}_{L}\rightarrow \pi^{0} \nu \bar{\nu}$ decay. This decay, which directly breaks the CP symmetry, is highly suppressed in the Standard Model (SM), and has small theoretical uncertainties, is sensitive to new physics beyond the SM. The KOTO experiment has been accumulating physics data since 2013 with several detector and DAQ upgrades. We are finalizing the analysis of the dataset taken in 2016-2018. The status of the 2016-2018 data analysis is reported in this paper.

The J-PARC Hadron Experimental Facility was constructed with an aim to explore the origin and evolution of matter in the universe through experiments with intense particle beams. In the past decade, many results from particle and nuclear physics experiments have been obtained at the present facility. To expand the physics programs to as yet unexplored regions, the extension project of the Hadron Experimental Facility has been extensively discussed. This contribution presents the physics of the extension of the Hadron Experimental Facility to resolve issues related to strangeness nuclear physics, hadron physics, and flavor physics.

The KOTO experiment is dedicated to study the rare decay $K^0 _L\rightarrow \pi^0 \nu \bar\nu$ at the J-PARC 30 GeV Main Ring. The $K^0 _L\rightarrow \pi^0 \nu \bar\nu$ decay breaks the CP symmetry directly and is highly suppressed in the Standard Model (SM). Thus, this decay is sensitive to new physics beyond the SM, in particular new sources of CP violation. After the first physics run in 2013, the KOTO collaboration improved the detector in order to suppress the backgrounds newly found in the analysis. We resumed physics run in 2015 and collected about 20 times larger amount of data in the year. From the 2015 data analysis, no events were observed with the expected background of $0.4\pm0.18$. We set an upper limit of $3.0\times10^{-9}$ at the 90% confidence level on the branching ratio. The result improves the previous limit by an order of magnitude.

timated to be 0:13 0:115= p e[GeV] 0:005=e[GeV] ns. The energy resolution and position resolution of the CsI calorimeter with the total energy E are estimated to be E=E = 0:99% 1:74%= p E[GeV] and po s = 2:50 4:40= p E[GeV] [mm], respectively. These results are comparable to the design values which were assumed in the KOTO proposal. One of the advantages of the KOTO CsI calorimeter is its capability to record shower shapes with its segmentation. By using shower shape information, we can suppress kinds of backgrounds involving showers made by particles other than a single photon.

The KOTO experiment [1] is a rare kaon decay experiment at J-PARC in Ibaraki. The goal of KOTO experiment is to discover the KL → πνν decay, and measure its branching ratio. The standard model predicts its branching ratio to be 2.4 × 10 [2], while the current upper limit of the branching ratio is 2.6×10(90%CL)[3]. KOTO is designed to improve the sensitivity by 3 orders of magnitude from the current upper limit. KOTO experiment took the first physics run in May 2013. With the high intensity proton beam from J-PARC, the counting rate of detectors will become a few MHz. If two or more pulses arrive at detector within a short period of time, those pulses will merge into one pulse. In order to get energy and timing information of each pulse from such an overlapped waveform, we record waveform of each detector pulse with 125 MHz ADC. The inputs to the ADC chip are widened to be in gaussian-shape with the 10 pole Bessel filter in advance of the sampling to get enough data points with detector signals (Figure1). This technique also increases probability of overlapping. Overlapped waveform is observed even in KOTO physics run in 2013 (Figure 2) and pulse shape analysis is necessary for analysis. I developed a new method to identify pulses from overlapped waveform. In this presentation, pulse identification method and its performance will be reported.

In this paper, Schur stability for a linear combination of polynomials is studied. In order to investigate this stability, we first study some important properties of the transformation matrix derived by using the bilinear transformation. And then, under certain assumptions, necessary and sufficient conditions for the linear combination of k polynomials to be Schur stable are obtained.

Recent studies have demonstrated that intermittent administration of parathyroid hormone (PTH) enhances osteogenesis (hard callus formation) and increases mechanical strength in experimental fracture healing. Thus far, however, effects of PTH on chondrogenesis (soft callus formation) during fracture healing have not been fully elucidated. In the present study, we analyzed the underlying molecular mechanism by which exogenous PTH would affect chondrogenesis in a model of experimental fracture healing. Unilateral femoral fractures were produced in 2-month-old Sprague-Dawley rats. Daily subcutaneous injections of 10 microg/kg of recombinant human PTH(1-34) [rhPTH(1-34)] were administered over a 28-day period of fracture healing. Control animals were injected with vehicle solution (normal saline) alone. The results showed that, on day 14 after fracture, cartilage area in the PTH-treated group was significantly increased (1.4-fold) compared with the controls, but this increase was not observed at days 21 and 28. In the early stage of chondrogenesis (days 4-7), cell proliferation, expressed as the rate of proliferating cell nuclear antigen-positive cells, was increased in mesenchymal (chondroprogenitor) cells but not chondrocytes in the PTH-treated group compared with controls. In addition, gene expression of SOX-9 was up-regulated in the PTH-treated group on day 4 (1.4-fold), and this was accompanied by enhanced expression of pro-alpha1 (II) collagen (1.8-fold). After 14 days, there were no significant differences between groups in either cell proliferation or the expression levels of cartilage differentiation-related genes (SOX-9, pro-alpha1 (II) collagen, pro-alpha1 (X) collagen and osteopontin). These results suggest that intermittent treatment with low-dose rhPTH(1-34) induces a larger cartilaginous callus but does not delay chondrocyte differentiation during fracture healing.

Recent reports have demonstrated that intermittent treatment with parathyroid hormone (1-34) [PTH(1-34)] increases callus formation and mechanical strength in experimental fracture healing. However, little is known about the optimal dose required for enhancement of fracture repair or the molecular mechanisms by which PTH regulates the healing process. In this study, we analyzed the underlying molecular mechanisms by which PTH affects fracture healing and tested the hypothesis that intermittent low-dose treatment with human PTH(1-34) can increase callus formation and mechanical strength. Unilateral femoral fractures were produced and a daily subcutaneous injection of 10 microg/kg of PTH(1-34) was administered during the entire healing period. Control animals were injected with vehicle solution alone. The results showed that on day 28 and day 42 after fracture, bone mineral content (BMC), bone mineral density (BMD), and ultimate load to failure of the calluses were significantly increased in the PTH-treated group compared with controls (day 28, 61, 46, and 32%; day 42, 119, 74, and 55%, respectively). The number of proliferating cell nuclear antigen (PCNA)-positive subperiosteal osteoprogenitor cells was significantly increased in the calluses of the PTH-treated group on day 2, and TRAP+ multinucleated cells were significantly increased in areas of callus cancellous bone on day 7. The levels of expression of type I collagen (COLlA1), osteonectin (ON), ALP, and osteocalcin (OC) mRNA were increased markedly in the PTH-treated group and accompanied by enhanced expression of insulin-like growth factor (IGF)-I mRNA during the early stages of healing (days 4-7). The increased expression of COL1A1, ON, ALP, and OC mRNA continued during the later stages of healing (days 14-21) despite a lack of up-regulation of IGF-I mRNA. These results suggest that treatment of fractures with intermittent low dose PTH(1-34) enhances callus formation by the early stimulation of proliferation and differentiation of osteoprogenitor cells, increases production of bone matrix proteins, and enhances osteoclastogenesis during the phase of callus remodeling. The resultant effect to increase callus mechanical strength supports the concept that clinical investigations on the ability of injectable low-dose PTH(1-34) to enhance fracture healing are indicated.

The KOTO experiment aims to discover the rare decay $K^{0}_{L}\rightarrow \pi^{0} \nu \bar{\nu}$ at J-PARC. This mode breaks the CP symmetry directly and is highly suppressed in the Standard Model. Thus the mode is sensitive to new physics, in particular to the models related to CP violation. We performed the first physics run in May 2013. Although the data taking was terminated after 100 hours due to an accident, the single event sensitivity for the $K^{0}_{L}\rightarrow \pi^{0} \nu \bar{\nu}$ decay reached $1.29\times10^{-8}$, which was comparable to the sensitivity of the prior experiment. We observed one candidate event while $0.36\pm0.16$ background events were expected., Comment: Proceedings of the 8th International Workshop on the CKM Unitarity Triangle (CKM 2014), Vienna, Austria, September 8-12, 2014

The J-PARC Hadron Experimental Facility was constructed with an aim to explore the origin and evolution of matter in the universe through the experiments with intense particle beams. In the past decade, many results on particle and nuclear physics have been obtained at the present facility. To expand the physics programs to unexplored regions never achieved, the extension project of the Hadron Experimental Facility has been extensively discussed. This white paper presents the physics of the extension of the Hadron Experimental Facility for resolving the issues in the fields of the strangeness nuclear physics, hadron physics, and flavor physics., 261 pages, 186 figures