EFFECTS OF REGIONAL VS. ECOLOGICAL FACTORS ON PLANT SPECIES RICHNESS: AN INTERCONTINENTAL ANALYSIS

Conclusions from past studies on the roles that historical and regional factors and contemporary and ecological factors have played in regulating large-scale patterns of species richness have been controversial. Conflicting past results were likely affected by differences in the range of environments analyzed and the scales of observation. Eastern North America and eastern Asia are ideal regions for examining the relative effects of historical and regional factors and contemporary and ecological factors on large-scale patterns of plant species richness because these two regions are closely matched in terms of climate and because their floras originated from the same paleoflora but have experienced different histories of development since the late Paleogene when climate cooling caused their separation. We report on a comprehensive data set of 471 floras ranging from 10 km2 to 4.7 x 10(6) km2 and spanning a wide range of climate and latitude (from 21 degrees to 55 degrees N) to examine whether the contribution of region relative to climate persists from small to large floras and increases from cooler to warmer climates. We found that eastern Asia is richer than eastern North America when sample area, maximum elevation, and climate are accounted for, that this difference diminishes toward higher latitudes, and that elevation plays a much stronger role in eastern Asia than in eastern North America. Our analysis reconciles contemporary/ecological and historical/regional explanations for species richness variation and helps explain why different conclusions have been reached by different authors working in the same geographical areas: the strength of the region effect itself varies with location and range of climatic conditions of the observations

韓国済州島の蘚類植物相: 追加記録と更新された総目録

The updated checklist of the mosses from Jeju Island, Korea contains 225 specific and infraspecific taxa in 109 genera and 42 families. It includes all moss names recorded for the Island by literature. Fifty three new records of species are added to the moss flora of Jeju Island, including 12 records new to Korea.本硏究を通じて韓国済州島からの蘚類の総目録は109属, 42科におよぶ225の種ならびに種下分類群であることが明らかになった。これは文献によってこれまで済州島から記録されたすべての蘚類を含むものである。新たに53種が済州島の蘚類植物相に追加され, その中12種は韓国から最初に記録されるものである

In vitro selection of salt-tolerant Ailanthus altissimaSwingle

Salt-tolerant cell lines of Ailanthus altissima were selected from callus derived protoplasts. Murashige–Skoog (MS) liquid medium incorporated with various concentrations of NaCl was employed to enrich salt-tolerant A. altissima cell lines. Salt-resistant A. altissima cells were transferred on MS solid medium supplemented with 2.5 μM 2,4-dichlorophenoxy acetic acid (2,4-D), 0.5 μM benzyl adenine (BA) and various NaCl concentrations. The callus was cultured on MS medium containing NaCl for 5 months, to determine the survival rate as an index of salt tolerance. The measurement of growth parameters for salt-tolerant cells showed that the selected plant cell lines grew better than the unselected ones at all levels of NaCl tested. The salt-tolerant callus accumulated proline in correlation to the concentration of salts. Media supplemented with BA induced shoot differentiation of salt-resistant A. altissima cells

韓國鬱陵島から蘚類植物相の新たな記録

本研究により，韓國鬱陵島の蘚類植物相は，24科50 属93 種からなることが判明した。これは過去に鬱陵島で記録されていた種数のほぼ3 倍にあたる。本研究によってはじめて韓國の蘚類植物相に追加された18 種を含め，鬱陵島ではこの度の研究により，新たに7 科21 属56 種が見つかった。この島の蘚類植物相は，朝鮮半島よりも日本にはるかに近いことが判った

Prognostic factors for aorta remodeling after thoracic endovascular aortic repair of complicated chronic DeBakey IIIb aneurysms

ObjectivesThe use of thoracic endovascular aortic repair (TEVAR) for chronic DeBakey III type b (CDIIIb) aneurysms is controversial. We analyzed the potential prognostic factors affecting aorta remodeling after this procedure.MethodsA total of 20 patients with CDIIIb aneurysms underwent TEVAR, with full coverage of reentry tears at the descending thoracic aorta. The potential factors affecting false lumen (FL) remodeling were analyzed, including reentry tears (communicating channels visible on the computed tomography angiogram), large intimal tears below the stent graft (≥2 consecutive axial cuts on the computed tomography angiogram), visceral branches arising from the FL, and intercostal arteries (ICAs) arising from the FL.ResultsAll the patients had uneventful in-hospital courses; 2 patients (10%) required reintervention during the follow-up period. Thirteen patients (65%) had complete thrombosis of the FL at stent graft segment. Compared with the complete thrombosis group, the partial thrombosis group had more reentry tears (1.8 vs 2.3, P = .48), large intimal tears (0.8 vs 1.7, P < .05), visceral branches arising from the FL (1.2 vs 2.3, P < .05), and ICAs arising from the FL (3.8 vs 5.1, P = .35). Reentry tears, visceral branches, and ICAs from the FL were significant negative prognostic factors for FL shrinkage (P < .05).ConclusionsAlthough reentry tears above the celiac trunk were fully covered, the visceral branches and ICAs from the FL and all communicating channels below the celiac trunk kept the FL pressurized and were unfavorable prognostic factors for aorta remodeling after TEVAR for CDIIIb aneurysms

韓国南部の農村地帯の水草相、および水草相と土地利用・水質との関係

We carried out field research in the southern Korean Peninsula and Jeju Island, South Korea to describe the aquatic flora and its habitat of the Korean rural areas, including 32 sites in the peninsula and 16 sites on the island. The sites of the peninsula are irrigation ponds and reservoirs for rice fields. The sites of the island are ponds for the drinking water of domestic animals, and irrigation and washing of local people. The study sites with agriculturally intensive watersheds had high values of electric conductivity （EC） > 40 mS/m. We found 8 free-floating taxa, 9 floating-leaved taxa and 14 submerged taxa. Eleven taxa （e.g. Trapa japonica） were found in both areas. Thirteen taxa （e.g. Euryale ferox） were restricted to the peninsula. Seven taxa （e.g. Potamogeton natans） were restricted to the island. Although most of the taxa were found in waters with various EC values, several species （e.g. Nymphoides indica） were confined to waters with EC < 30 mS/m. Most of the confirmed taxa in this study are found in Japan. The abundant species （e.g. T. japonica） commonly dominate in nutrient-rich ponds in Japan. The aquatic flora of the study area was characterized by species characteristic of a wide distribution and/or eutrophic water. The aquatic flora includes seven species regarded as threatened in Korea. It also includes 15 Japanese threatened species, and 9 of them are rice weeds. Our study shows that ponds of Korean rural areas support diverse aquatic plants including rare and threatened species.韓国の農村地帯の水草相と水草の生育環境を把握することを目的に、朝鮮半島南部32か所と済州島16か所、計48か所において植物と水質の調査を行った。朝鮮半島の調査地は水田灌漑用のため池であり、済州島の調査地は家畜の飲料用と灌漑や洗い物用の池である。調査地のうち、農地に囲まれた池は、電気伝導度（EC）が40mS/m以上の高い値を示した。両地域で浮遊植物8種、浮葉植物9種、沈水植物14種を確認した。このうちヒシなど11種は朝鮮半島と済州島に共通であったが、オニバスなど13種は朝鮮半島、オヒルムシロなど7種は済州島のみに分布し、両地域の植物相に違いがあった。広範囲のEC値に分布する種が多かったが、ガガブタなどの数種はECが30mS/m以下の水域に分布が限られていた。ヒシなどの確認地点が多い種は、日本の富栄養な水域に繁茂する水草であった。調査地の水草相は、生育範囲の広い種と富栄養な水域の種で特徴づけられた。確認種には7種の韓国の絶滅危惧種が含まれていた。また15種の日本の絶滅危惧種も含まれ、そのうちの9種が水田雑草であった。今回の調査結果は、韓国の農村地帯のため池が、稀少種や絶滅危惧種を含む多様な水草の生育地として貴重な存在であることを示している