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The role of memory in affirming-the-consequent fallacy
No full textPeople tend to recognize that a transitive relation remains true even when its order is reversed. This affirming-the-consequent fallacy is thought to be uniquely related to human intelligence. It is generally thought that this fallacy is a byproduct of explicit reasoning at the moment of recognition of the reversed order. Here, we provide evidence suggesting a reconsideration of this account using an implicit memory paradigm, which minimizes the involvement of explicit reasoning. Specifically, we tested a two-stage memory model: (1) when a sequence of events is encoded, the memory of the reversed sequence is formed, resulting in the affirming-the-consequent fallacy, and (2) the memories of the forward and reversed sequences are integrated over time, reinforcing the fallacy. Results of behavioral and functional magnetic resonance imaging experiments were consistent with this memory-based model. Our findings suggest that the affirming-the-consequent fallacy may begin unwittingly when individuals memorize a tranjournal articl
Influence of Stark Broadening on Ion Temperature Measurement for ITER Divertor Diagnosis
No full textThe Stark broadening of a Be II line (1s^2 3d ^2D ? 1s^2 4f ^2F, 467.339 nm) under a magnetic field is evaluated with the divertor plasma of ITER in mind. The electron and ion perturbers are treated in the impact and static approximations, respectively. The perturbation term due to the magnetic field is included in the static approximation. The results show that the Stark broadening comes to be significantly large when the density is higher than 10^21 m^?3, and the ion temperature would be overestimated if the Stark broadening is not taken into account.journal articl
Development of Novel Nomograms to Predict 5- and 7-Year Biochemical-Recurrence-Free Survival in High-Risk Prostate Cancer Patients After Carbon-Ion Radiotherapy and Androgen Deprivation Therapy
No full textBackground: The aim of this study was to develop nomograms predicting 5-
and 7-year biochemical-recurrence (BCR)-free survival in high-risk prostate cancer (PCa) patients treated with carbon-ion radiotherapy (CIRT) and androgen deprivation therapy (ADT). Methods: We retrospectively evaluated 785 high-risk PCa patients treated with CIRT and ADT. Based on the least absolute shrinkage and selection operator model, two nomograms predicting 5- and 7-year BCR-free survival were developed and internally validated. The ability of each nomogram to predict BCR-free survival was determined by calculating the area under the survival curve (AUC). Results: The 5- and 7-year BCR-free survival rates were 92.1% and 89.3%, respectively. Age, prostate-specific antigen level,
clinical T stage, and Gleason score were incorporated into the nomogram redicting 5year BCR-free survival. In addition to these variables, the percentage of positive biopsy cores was also added to the nomogram predicting 7-year BCR-free survival. The AUC value of each nomogram showed suboptimal-to-good discrimination. Conclusions: We developed the first nomograms accurately predicting BCR-free survival in high-risk PCa patients treated with CIRT and ADT. These nomograms will enable adequate understanding and explanation of BCR-free survival to patients when clinicians use them.journal articl
Initial demonstration of the Scratch-PET concept: an intraoperative PET with a hand-held detector
No full textPositron emission tomography (PET) is a valuable tool for diagnosing malignant tumors. Intraoperative PET imaging is expected to allow the more accurate localization of tumors that need resections. However, conventional devices feature a large detector ring that obstructs surgical procedures, preventing their intraoperative application. This paper proposes a new PET device, Scratch-PET, for image-guided tumor resection. The key feature of Scratch-PET is its use of a hand-held detector to scan the surgical field, ensuring open space for surgery while measuring annihilation radiation with a fixed detector array placed below the patient. We developed a prototype device using two detectors: the hand-held detector and a fixed detector, to demonstrate the feasibility of the proposed concept. Both detectors consisted of 16?×?16 arrays of lutetium yttrium orthosilicates (3?×?3?×?15 mm3) coupled one-to-one with 16?×?16 silicon photomultiplier arrays. The position and orientation of the hand-held detector are tracked using an optical tracking sensor that detects attached markers. We measured a 22Na multi-rod phantom and two 22Na point sources separately for 180 s while moving the hand-held detector. The rod diameters were 6.0, 5.0, 4.0, 3.0, 2.2, and 1.6 mm. Each point source was placed at the field-of-view center and 35 mm off-center which was outside the sensitive area when the hand-held detector was positioned facing the fixed detector. The 2.2 mm rods were partially resolved, and both point sources were successfully visualized. The potential of the proposed device to visualize small tumors was validated.journal articl
Assessing interstitial fluid dynamics in type 2 diabetes mellitus and prediabetes cases through diffusion tensor imaging analysis along the perivascular space.
No full textGlymphatic system in type 2 diabetes mellitus (T2DM) but not in the prodrome, prediabetes (Pre-DM) was investigated using diffusion tensor image analysis along the perivascular space (DTI-ALPS). Association between glymphatic system and insulin resistance of prominent characteristic in T2DM and Pre-DM between is yet elucidated. Therefore, this study delves into the interstitial fluid dynamics using the DTI-ALPS in both Pre-DM and T2DM and association with insulin resistance.journal articl
Methemoglobin-Encapsulating Liposome: A Low-Risk Intravascular Contrast Agent for Magnetic Resonance Imaging.
No full textHemoglobin shows different contrasts on magnetic resonance imaging (MRI) depending on the iron and oxygenation states of heme. Functional brain MRI utilizes the differences in the concentrations of oxyhemoglobin and deoxyhemoglobin in cerebral blood vessels; blood clots produce strong magnetic susceptibility effects. We hypothesized that methemoglobin (MetHb)-based nanoparticles can act as MRI contrast agents because MetHb levels in red blood cells affect relaxivity and are strictly regulated to <1% in the blood. Herein, we describe the synthesis of methemoglobin-encapsulated liposomes (Met-HbVs) as contrast agents for MRI. Met-HbV, with a size of approximately 200 nm, increased longitudinal relaxivity () by 2.44-fold compared with hemoglobin-encapsulated liposomes . In contrast, the transverse relaxation capacity () of Met-HbVs was similar to that of the hemoglobin-encapsulated liposomes. Owing to its relaxivity, Met-HbV enhanced the signal intensity on T1-weighted images and angiography, especially in the veins. Furthermore, deleterious biological responses were seldom observed after Met-HbV administration in mice with chronic renal failure. In conclusion, Met-HbV possesses potential as a vascular contrast agent in MRI for angiography, with advantages over gadolinium-based contrast agents in terms of safety for patients with renal failure. To the best of our knowledge, this is the first report demonstrating the potential of MetHb as a biomaterial for contrast agents in MRI.journal articl
Particle Therapy for Intrahepatic Cholangiocarcinoma: A Multicenter Prospective Registry Study, Systematic Review and Meta-Analysis.
No full textA prospective study was started in May 2016 to evaluate the efficacy and safety of particle therapy for intrahepatic cholangial carcinoma (ICC). To compare treatment modalities, we also conducted a meta-analysis of literature data and a systematic comparison using registry data.journal articl
Upgrade of the KWS-2 high-intensity/extended-Q-range SANS diffractometer of JCNS for soft matter and biophysics: in situ SEC, controlled in situ RH/T variation and WANS detection
No full textThe KWS-2 small-angle neutron scattering (SANS) diffractometer operated by
Juelich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum,
Garching, Germany, is dedicated to the investigation of mesoscopic multi-scale
structures and structural changes due to rapid kinetic processes in soft
condensed matter and biophysical systems. Following requests from the user
community, it has been repeatedly upgraded with respect to the most important
methodological parameters of an instrument of this type, namely the intensity
on the sample, the instrumental resolution and the minimum scattering variable
Qmin. Here we report on further specific improvements to the sample environment and detection capabilities which have just been completed or are being implemented. Complementary size-exclusion chromatography (SEC) for in situ protein purification was developed and optimized at KWS-2 to provide the
instrument with biological samples of controlled quality. The instrument is also
currently being equipped with a wide-angle neutron scattering (WANS)
detector which will allow it to bridge the atomic and mesoscale, benefiting from
the instrument’s adjustable resolution down to 2%. For controlled
relative humidity and temperature on ionic conductive samples for
energy applications or biomembranes for biophysical and health applications, a
precise dew point generator has recently been characterized and commissioned;
this offers great versatility with regard to varying the contrast in situ in the beam
on hydrated samples.journal articl
Editorial: State-of-the-Art Muscle Physiology Research: From Single Molecules and Cells to Living Organisms
No full textSince the turn of the 21st century, scientists have applied various optical and molecular biological technologies to ascertain critical details on the structure and function of skeletal and cardiac muscles in health and disease. As such, the newly developed technologies will further deepen our understanding of the molecular and cellular mechanisms of striated muscle contraction and relaxation, thereby providing new prospective means to facilitate the diagnosis and treatment of various diseases, especially in the heart. This Research Topic covers recent advances in the studies on the hierarchical structure and function of skeletal and cardiac muscles, as well as the pre- and post-natal development of the heart.journal articl
Microstructural Characterization of Irradiated SrTiO3 Using High-Resolution STEM-EDS analysis
No full textTo gain a deeper understanding of radiation-induced amorphization, high-resolution ABF/ADF and STEM-EDS techniques were utilized for the irradiation of single crystal SrTiO3 with 160 keV O+ at room temperature. The results show that oxygen column damage increased with irradiation dose, however, the local specific damage level was determined from the depth profiles of irradiation dose, dose rate, and amount of implanted oxygen at different fluences. HAADF observations indicated a decrease in Sr and Ti column intensities with increasing irradiation dose, initially monotonic, then slowing above 5 dpa and accelerating again above 30 dpa. This behavior suggests that the accumulation of topological and chemical disordering depends on the damage level. STEM-EDS analysis revealed periodic concentration changes of Sr and Ti based on the atomic arrangement of the crystal in unirradiated SrTiO3. By comparing irradiated and unirradiated samples, the concentration changes associated with oxygen implantation and the formation of chemical and topological disordering were confirmed. These results highlight the potential of STEM-EDS to characterize the evolution of irradiated microstructures in SrTiO3, even with a relatively low spatial resolution probe. Consequently, this study offers valuable insights into the mechanisms of radiation-induced instability of SrTiO3, contributing to the visualization of irradiation microstructure in various materials as well.journal articl