230 research outputs found
Atypia and Surface Structure of Superficial Neoplasms of the Colon Less Than 10 mm in Diameter
Histological specimens of 30 distinct adenomas and 30 distinct carcinomas were studied by image analysis to quantify nuclear size and shape. These data were used to derive a discriminant equation, which permitted the lesions to be classified into two groups based on nuclear atypia. Next, 50 superficial type tumors of the colon (34 IIa lesions, 9 IIc + IIa lesions, and 7 IIc lesions) <10 mm in longest diameter were similarly analyzed. These lesions were classified into a high atypia index group (HAI group, 14 lesions) and a low atypia index group (LAI group, 36 lesions) by the above discriminatory equation. Differences between these two groups in surface structure, marginal zone properties, and macroscopic type, assessed using a dissecting microscope, were studied. A hyperplastic shape of the tubular orifice was seen at the marginal zone in 10 lesions (27.7%) in the LAI group and 11 lesions (78.5%) in the HAI group. This difference was significant. Surface structure and macroscopic type were not correlated with the degree of atypia. The tubular density in lesions showing a hyperplastic pitted pattern at their border was 77.40, significantly higher than that for lesions without such a pattern (73.12). The contribution of various variables to surface structure, marginal zone properties, and macroscopic type was studied by discriminant analysis. A high correlation was found between marginal zone properties and tubular density. Since lesions with high nuclear atypia tend to have high tubular density, marginal zone properties were secondarily correlated with the level of nuclear atypia. Observation of the marginal zone properties of lesions was thus suggested to be helpful in the diagnosis of lesions with severe atypia
Early Science Result from the Japanese Virtual Observatory: AGN and Galaxy Clustering at z = 0.3 to 3.0
We present the result of projected cross correlation analysis of AGNs and
galaxies at redshifts from 0.3 to 3.0. The Japanese Virtual Observatory (JVO)
was used to obtain the Subaru Suprime-Cam images and UKIDSS catalog data around
AGNs. We investigated 1,809 AGNs, which is about ten times larger a sample than
that used in previous studies on AGN-galaxy clustering at redshifts larger than
0.6. 90% of the AGN samples are optically-selected AGN from the SDSS and 2dF
catalogs. The galaxy samples at low redshift includes many redder objects from
UKIDSS survey, while at higher redshift they are mainly blue galaxies from
Suprime-Cam. We found significant excess of galaxies around the AGNs at
redshifts from 0.3 to 1.8. For the low redshift samples (), we obtained
correlation length of 5--6 Mpc (), which
indicates that the AGNs at this redshift range reside in a similar environment
around typical local galaxies. We also found that AGNs at higher redshift
ranges reside in a denser environment than lower redshift AGNs; For AGNs, the cross correlation length was measured as 11
Mpc (). Considering that our galaxies sample is based on
optical observations with Suprime-Cam at the redshift range, it is expected
that blue star-forming galaxies comprise the majority of objects that are
observed to be clustered around the AGNs. It is successfully demonstrated that
the use of the archive through the Virtual Observatory system can provide a
powerful tool for investigating the small scale environment of the intermediate
redshift AGNs.Comment: accepted to PASJ, 36 pages, 21 figures, this is an accepted versio
Distribution and management of non-native squirrels in Japan
Three species of alien squirrels have been confirmed to have been introduced in Japan: Tamias sibiricus, Callosciurus erythraeus (including the species complex C. finlaysonii), and Sciurus vulgaris. Japan is home to endemic squirrel species S. lis, Petaurista leucogenys, and Pteromys momonga, as well as endemic subspecies S. vulgaris orientis, T. sibiricus lineatus, and Pteromys volans orii. It is important to address the issue of damage to ecosystems caused by alien species, including the conservation of endemic species. Chipmunks (T. sibiricus) have become established in at least 11 of 47 prefectures, but no measures have been taken because the damage is not yet apparent. Pallas’s squirrels (C. erythraeus) that were reared in petting zoos for tourism purposes escaped and have become established in at least 17 localities in 13 prefectures. Because of the high population densities and significant damage caused by this species, removal measures have been implemented in at least 12 locations. The species is now eradicated or near eradication in four locations. Eurasian red squirrels (S. vulgaris) have become established at two sites in central Honshu and Kyushu. Due to possible hybridization with the Japanese squirrel (S. lis), trapping began in 2014 with the aim of eradication. This review summarizes the measures taken in Japan to conserve endemic species and emphasizes the importance of the involvement of researchers in early action
Papillo-Choledochectomy in the Operative Management of Mucosal Neoplasms of the Periampullary Region
Two patients with mucosal cancer of the periampullary region were treated with papillocholedochectomy,
which entails removal of the papilla of Vater and the whole length of the common bile duct. The neoplasm is dissected out through the plane between the duodenal circular and longitudinal muscles, deep to the sphincter of Oddi and the fibromuscular layer of the bile duct. Pathological examination showed that cancer was confined to the mucosal layer without stromal invasion, and that the operation achieved radical cure. For mucosal cancer, papillo-choledochectomy is
an alternative to pancreatoduodenectomy, provided that repeated frozen-section studies confirm the
completeness of excision
Mammalian Diversity of Gunung Ledang, Johor, Peninsular Malaysia
Mammals play a crucial role for the biotic processes of the rainforest ecosystem. Studying their behaviour and biology are vital to fully understand the jigsaw of rainforest dynamics. This study was made to update the diversity checklist of mammals in Gunung Ledang. This study was done in Taman Negara Johor; Gunung Ledang (2.37°N, 102.60°E) where it is known to be the highest mountain (1,276 m asl.) in the southern Malay Peninsula. This study was conducted from July 2018 to April 2019. In total, 22 cameras were installed along three nature trails which are Sagill trail, Telekom Trail, and Resort Trail. Overall, a total of 31 species of terrestrial mammals from small- to large-sized were recorded in our camera trapping study of 3434 camera-days.Mammals such as the Leopard (Panthera pardus), Sumatran Serow (Capricornis sumatraensis), and Malayan Tapir (Tapirus indicus) were caught in the videos of camera trap. This showed that the diversity of mammals in Gunung Ledang is quite high. Tthis paper already gave valuable insights in a rainforest guild that is highly diverse and of outstanding value to the forest ecosystem. Management plans and strategy to conserve the mammals in Gunung Ledang can be done as accordingly afterwards
A SCINTIGRAPHIC STUDY OF MASS PERISTALSIS IN HUMAN COLON
Although many attempts have been made to study human colonic motility, the colonic transit is still poorly understood. Both spontaneous and neostigmine-induced peristalsis of the colon were studied with scintigraphy. A polythene tube was inserted into the cecum through a colonofiberscope. 37 MBq of ⁹⁹ᵐTc-DTPA and 75 ml of saline were instilled and dynamic scan was begun. Eight healthy volunteers were examined by the method above mentioned. The sampling time was set at fifteen seconds in six persons and three seconds in the rest. 0.5 mg of neostigmine was injected intravenously to stimulate the paristalsis when no peristalsis occurred within thirty minutes after the study was begun. Dynamic scanning was performed for sixty to ninety minutes. This scintigraphic study revealed that the spontaneous and induced peristalsis were almost identical on colonogram. ⁹⁹ᵐTc-DTPA solution was propelled from the cecum and ascending colon to the sigmoid colon or the rectum for about fifteen seconds during mass peristalsis. Colonogram
(time-activity curve) enables us to analyze mass peristalsis easily and more objectively
than colonoscintigram. The spontaneous and neostigmine-induced peristalsis seemed to be almost identical in all but one of eight subjects
Effects of nonlethal tourist activity on the diel activity patterns of mammals in a National Park in Peninsular Malaysia
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Measurement of a Phase of a Radio Wave Reflected from Rock Salt and Ice Irradiated by an Electron Beam for Detection of Ultra-High-Energy Neutrinos
We have found a radio-wave-reflection effect in rock salt for the detection
of ultra-high energy neutrinos which are expected to be generated in Greisen,
Zatsepin, and Kuzmin (GZK) processes in the universe. When an UHE neutrino
interacts with rock salt or ice as a detection medium, a shower is generated.
That shower is formed by hadronic and electromagnetic avalanche processes. The
energy of the UHE neutrino shower converts to thermal energy through ionization
processes. Consequently, the temperature rises along the shower produced by the
UHE neutrino. The refractive index of the medium rises with temperature. The
irregularity of the refractive index in the medium leads to a reflection of
radio waves. This reflection effect combined with the long attenuation length
of radio waves in rock salt and ice would yield a new method to detect UHE
neutrinos. We measured the phase of the reflected radio wave under irradiation
with an electron beam on ice and rock salt powder. The measured phase showed
excellent consistence with the power reflection fraction which was measured
directly. A model taking into account the temperature change explained the
phase and the amplitude of the reflected wave. Therefore the reflection
mechanism was confirmed. The power reflection fraction was compared with that
calculated with the Fresnel equations, the ratio between the measured result
and that obtained with the Fresnel equations in ice was larger than that of
rock salt.Comment: 6 Pages, 5th International Workshop on Acoustic and Radio EeV
Neutrino Detection Activitie
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