45 research outputs found
Case-based similar image retrieval for weakly annotated large histopathological images of malignant lymphoma using deep metric learning
In the present study, we propose a novel case-based similar image retrieval
(SIR) method for hematoxylin and eosin (H&E)-stained histopathological images
of malignant lymphoma. When a whole slide image (WSI) is used as an input
query, it is desirable to be able to retrieve similar cases by focusing on
image patches in pathologically important regions such as tumor cells. To
address this problem, we employ attention-based multiple instance learning,
which enables us to focus on tumor-specific regions when the similarity between
cases is computed. Moreover, we employ contrastive distance metric learning to
incorporate immunohistochemical (IHC) staining patterns as useful supervised
information for defining appropriate similarity between heterogeneous malignant
lymphoma cases. In the experiment with 249 malignant lymphoma patients, we
confirmed that the proposed method exhibited higher evaluation measures than
the baseline case-based SIR methods. Furthermore, the subjective evaluation by
pathologists revealed that our similarity measure using IHC staining patterns
is appropriate for representing the similarity of H&E-stained tissue images for
malignant lymphoma
Interactions of fragment ions of tetradecane with solid surfaces
Vapors of tetradecane (C[14]H[30]) were ionized by electron bombardment. The generated fragment ions such as C[3]H[7], C[6]H[13], and C[12]H[25] ions were separated by an E Ć B filter (Wien filter) and accelerated toward Si(1 0 0) substrates. Thickness measurements showed that thin films were deposited on the Si substrates by C[3]H[7]- and C[6]H[13]-ion irradiation, although the Si substrate surface was predominantly sputtered by C[12]H[25] ions. Rutherford backscattering spectroscopy showed that the irradiation damage by the fragment-ion beams decreased with the increasing molecular weight of the fragment ions at the same acceleration voltage. Furthermore, Raman spectra as well as X-ray photoelectron spectroscopy measurements showed that DLC films were formed by C[3]H[7]- and C[6]H[13]-ion irradiation with the film thickness being larger in case of C[3]H[7]. On the contrary, for C[12]H[25]-ion irradiation, chemical sputtering occurred by surface reactions of hydrogen and methyl radicals with silicon atoms. The chemical reaction at the irradiated substrate surface could be enhanced by the higher temperatures achieved by the high energyādensity irradiation effect of the polyatomic ions
Inferior vena cava filter misplacement in the right atrium and migration to the right ventricle followed by successful removal using the endovascular technique: A case report and review of the literature
Inferior vena cava filters are effective for preventing the passage of thrombi into the pulmonary arteries in patients with pulmonary embolism and deep vein thrombosis. These filters are indicated in patients with contraindications to anticoagulant therapy or in patients with recurrent acute pulmonary embolism despite the administration of anticoagulant therapy. However, the occurrence of filter-related complications, such as filter migration to the heart, has been increasing. Herein, we report a case of OptEase inferior vena cava filter misplacement in the right atrium. Although the filter migrated to the right ventricle, it was successfully removed and repositioned in the inferior vena cava using endovascular techniques. Unfortunately, moderate tricuspid regurgitation developed, due to the damage to the tricuspid valve that was caused by the procedure. We have also reviewed the relevant literature and discussed the possible strategies for managing cases of filter migration to the heart and preventing filter misplacement
Nanostructured SiāGe thermoelectric material for 1200 V/W highly sensitive infrared thermopile sensor device
In this paper, we report the characteristics of a thermopile infrared sensor in which a nanostructured SiāGe thermoelectric material is used. Although the thermopile infrared sensor is capable of being operated without power consumption, a challenge has been improving its sensitivity. With the aim of improving its sensitivity, we have realized a nanostructured SiāGe thermoelectric material with low thermal conductivity (0.8 W/m K or less) by forming nanocrystals through heat treatment of amorphous SiāGe. The thermopile infrared sensor composed of this material exhibited a high sensitivity of 1200 V/W at a pressure of 1.0 Ć 10ā1Ā Pa or less
Fragility and an extremely low shear modulus of high porosity silicic magma
The rheology and strength of bubbly magma govern eruption dynamics by determining the possibility of fragmentation of ascending magmas. They are also required parameters for understanding seismic monitoring. We measured the rheology and strength of high porosity rhyolitic magma at 500ā950 Ā°C. The measured shear modulus and strength are several orders of magnitude lower than bubble-free rhyolite melt, implying that high porosity magma cannot avoid fracturing during magma ascent. The occurrence of fractures is observed in the low-temperature magma (ā¤800 Ā°C). In this temperature range, the measured attenuation is low. That is, the elastic energy originated by deformations avoids attenuation and is stored in the bubbly magma until released by fracturing (Q > 1). The newly found porosity-dependent strength based on our measurements comprehensively explains three different fragmentation criteria that have been previously proposed independently. Our measurements also show that the shear modulus becomes lower by increasing porosity, which can slow the shear wave velocity. These results suggest that knowing the attenuation of the seismic wave is useful to evaluate magma temperature and the possibility of a fragmentation event that may determine subsequent volcanic activities.This work is supported by JSPS KAKENHI grants 16H04042 and 19H00721
Synthesis of Monodispersed Submillimeter-Sized Molecularly Imprinted Particles Selective for Human Serum Albumin Using Inverse Suspension Polymerization in Water-in-Oil Emulsion Prepared Using Microfluidics
We synthesized monodispersed submillimeter-sized
(100 Ī¼mā1
mm) microgels by inverse suspension polymerization of water-soluble
monomer species with a photoinitiator in water-in-oil (W/O) droplets
formed by the microchannel. After fundamental investigations of the
selection of suitable surfactants, surfactant concentration, and flow
rate, we successfully prepared monodispersed submillimeter-sized W/O
droplets. Because radical polymerization based on thermal initiation
was not appropriated based on colloidal stability, we selected photoinitiation,
which resulted in the successful synthesis of monodispersed submillimeter-sized
microgels with sufficient colloidal stability. The microgel size was
controlled by the flow rate of the oil phase, which maintained the
monodispersity. In addition, the submillimeter-sized microgels exhibit
high affinity and selective binding toward HSA utilizing molecular
imprinting. We believe the monodispersed submillimeter-sized molecularly
imprinted microgels can be used as affinity column packing materials
without any biomolecules, such as antibodies, for sample pretreatment
to remove unwanted proteins without a pump system