Microscopic phase separation in the overdoped region of high-Tc cuprate superconductors

We propose a phenomenological model for high-$T_{c}$ superconductors (HTSC) assuming: (1) a microscopic phase separation between superconducting and normal-metal areas in the overdoped region; and (2) existence of a homogeneous superconducting phase only below the pseudo-gap $T^{*}$ line, which shows a sharp reduction towards $T^{*}\sim 0$ at a mildly overdoped critical concentration $x_{c}$. This model explains anomalous doping and temperature dependences of $n_{s}/m^{*}$ (superconducting carrier density / effective mass) observed in several overdoped HTSC systems. We point out an analogy to superfluid $^{4}$He/$^{3}$He films, and discuss an energetic origin of microscopic phase separation.Comment: 5 pages, 4 figure

Muon spin relaxation studies of incommensurate magnetism and superconductivity in stage-4 La2_{2}CuO4.11_{4.11} and La1.88_{1.88}Sr0.12_{0.12}CuO4_{4}

This paper reports muon spin relaxation (MuSR) measurements of two single crystals of the title high-Tc cuprate systems where static incommensurate magnetism and superconductivity coexist. By zero-field MuSR measurements and subsequent analyses with simulations, we show that (1) the maximum ordered Cu moment size (0.36 Bohr magneton) and local spin structure are identical to those in prototypical stripe spin systems with the 1/8 hole concentration; (2) the static magnetism is confined to less than a half of the volume of the sample, and (3) regions with static magnetism form nano-scale islands with the size comparable to the in-plane superconducting coherence length. By transverse-field MuSR measurements, we show that Tc of these systems is related to the superfluid density, in the same way as observed in cuprate systems without static magnetism. We discuss a heuristic model involving percolation of these nanoscale islands with static magnetism as a possible picture to reconcile heterogeneity found by the present MuSR study and long-range spin correlations found by neutron scattering.Comment: 19 pages, 15 figures, submitted to Phys. Rev. B. E-mail: [email protected]

Superfluid density of high-Tc cuprate systems: implication on condensation mechanisms, heterogeneity and phase diagram

Extensive muon spin relaxation measurements have been performed to determine the magnetic field penetration depth in high-Tc cuprate superconductors with simple hole doping, Zn-doping, overdoping, and formation of static SDW nano islands. System dependence of $n_{s}/m^{*}$ (superconducting carrier density / effective mass) reveals universal correlations between Tc and $n_{s}/m^{*}$ in all these cases with / without perturbation. Evidence for spontaneous and microscopic phase separation was obtained in the cases with strong perturbation, i.e., Zn-doping. overdoping and SDW nano-islands. The length scale of this heterogeneity is shown to be comparable to the in-plance coherence length. We discuss implications of these results on condensation mechanisms of HTSC systems, resorting to an analogy with He films, on regular and porous media, reminding essential features of Bose-Einstein, BCS and Kosterlitz-Thouless condensation/transition in 2-d and 3-d systems, and comparing models of BE-BCS crossover and phase fluctuations. We propose a new phase diagram for HTSC systems based on distinction between pair formation and superconducting phase fluctuations in the pseudogap region and spontaneous phase separation in the overdoped region. We also remind anomaly in BEDT and A3C60 systems similar to that in overdoped cuprates, seen in the evolution from superconducting to metallic ground state.Comment: 21 pages, 18 figures, invited papter presented at the HTSC Workshop, Williamsburg, Virginia, June 7-8, 2002, to appear in Solid State Communications (Special Issue edited by A.J. Millis, S. Uchida, Y.J. Uemura): contact [email protected]

Gastric cancer screening by combined assay for serum anti-Helicobacter pylori IgG antibody and serum pepsinogen levels — “ABC method”

The current status of screening for gastric cancer-risk (gastritis A, B, C, D) method using combined assay for serum anti-Helicobacter pylori (Hp) IgG antibody and serum pepsinogen (PG) levels, “ABC method”, was reviewed and the latest results of our ongoing trial are reported. It was performed using the following strategy: Subjects were classified into 1 of 4 risk groups based on the results of the two serologic tests, anti-Hp IgG antibody titers and the PG I and II levels: Group A [Hp(−)PG(−)], infection-free subjects; Group B [Hp(+)PG(−)], chronic atrophic gastritis (CAG) free or mild; Group C [Hp(+)PG(+)], CAG; Group D [Hp(−)PG(+)]), severe CAG with extensive intestinal metaplasia. Continuous endoscopic follow-up examinations are required to detect early stages of gastric cancer. Asymptomatic Group A, which accounts for 50–80% of all the subjects may be excluded from the secondary endoscopic examination, from the viewpoint of efficiency. Hp-infected subjects should be administered eradication treatment aimed at the prevention of gastric cancer

A test of Ohm's law

Thesis (B.S.)--University of Illinois, 1917.Typescript.Includes bibliographical references

屋久島におけるスギの立木本数の推定

Yakushima is an island located at about 130 km to the south of Kagoshima city. Total area and circumference of the island are equal to 500.56 km^2 and 100 km, respectively. The island has the shape which is similar to a circle. The distance between north and south capes of the island is about 28 km, while the distance between west and east capes of the island is about 24 km. Besides Mt. Miyanoura, the highest in Kyushu region, with the elevation of 1,935 m, there are also more than 30 mountains with the elevation of 1,000 m and avove. In relation to the above mentioned, 45,461 ha or 90.8% of total island area is covered by mountain forest. This is consisting of National Forest, Communual Forest and Private Forest with the area of 38,600 ha (84.9%), 1.705 ha (3.8%) and 5,156 ha (11.3%), respectively. The main species in the National Forest is Sugi (Cryptomeria japonica) with the ages of more than 1000 years and normally called as “Yakusugi”. Diameter (DEW) of the Yakusugi is larger than 120 cm. Meanwhile, in Yakushima, trees with DBH smaller than 120 cm are normally called as “Kosugi”. As the standing stock of Yakusugi is gradually decreases its protection and cultural treatment has been becoming a serious problem in the recent time. This study intended to obtain the basic data for the protection and cultural treatment of Yakusugi and to clarify the effective method for the estimation of the number of tree of Yakusugi. In relation to this purpose, an investigation by strip sampling has been conducted in Hanayama district, Shimo-Yaku Forest Region and Shiratani district, Kami-Yaku Forest Region. The investigated forest area are 175.13 ha in Hanayama district and 138.96 ha in Shiratani district. As the result, it was obtained that total number of Sugi trees in Hanayama district, with the significant level of 5%, is equal to 19947.3f4587.5 stems (The total number for Hinoki, Tsuga and Momi trees are equal to 875.7f716.4 stems, 2723.8±1317.2 stems and 389.7±468.5 stems, respectively). In Shiratani district, it was found that the total number of Sugi trees is equal to 18103.0±12278.2 stems (The total number Tsuga and Momi trees are equal to 1827.3±3117.2 stems and 548.9f625.7 stems, respectively). The larger-size trees with DBH of 120 cm and above, was found to equal to 17 stems and 11 stems of them are Yakusugi (these are covering 8.3% and 5.4% of total number of 204 stems, respectively). In Shiratani district, it was found that larger-size trees are amount to 2 stems and 1 stem of them is Yakusugi (these are covering 2% and 1% of total number of 99 stems, respectively). The interpretation of standing stock of Yakusugi by aerial photograph has not presented the expected result. This is because the aerial photograph esed in this study are old panchromatic photos taken in October 1963 and May 1969. And therefore, the different of crown form, tone and contrastly between Sugi and Tsuga or another needle-leave trees, was not clearly identified. However, the relations between DBH and crown diameter (CD) for Sugi and Tsuga present the different significantly. In the future, it is necessary to conduct the investigation by using the film which be able to present the clearly different characteristics of multispectral and reflection of different species, such as infrared film, infrared color film, false color film, digital color film, etc.屋久島は鹿児島市の南約130kmの洋上に位置し,東西約28km,南北24km,周囲100kmのほぼ円形の島で,面積500.56km^2を有する.ここには九州で一番高い1935mの宮之浦岳をはじめ,1,000m以上の山岳が30以上も連座している.そのため全島の90.8%に及ぶ45461haが山林となっている.地形は急峻で,起伏度もきわめて激しい.そのうち38600ha(84.9%)が国有林,1705ha(3.8%)が公有林,5156ha(11.3%)が私有林となっている.ヤクスギは主として国有林の中に生立し分布している.ヤクスギは樹齢1000年以上のものをいう.胸高直径(DBH)では120cm以上がその対象となっている.それ以下のものは屋久島ではコスギと称している.そのヤクスギが年々減少してきているため,現在,その保護と育成が問題となっている.本研究はヤクスギの保護と育成のための基礎資料をうること,および効率的な本数推定の方法を究明することを目的として,ヤクスギ,コスギを含むすべてのスギの立木本数の推定を,A.下屋久営林署管内花山地区(面積175.13ha),およびB.上屋久営林署管内白谷地区(面積138.96ha)を対象にしてストリップ調査により行なった.その結果,危険率5%(t_)により,A.花山地区で175.13ha当り19947.3±4587.5本(他にヒノキ875.7±716.4本,ツガ2723.3±1317.2本,モミ389.7±468.5本)となった.B.白谷地区では138.96ha当り18103.0±12278.2本(他にツガ1827.3±3117.2本,モミ548.9±625.7本)となった.なお,この中でDBH120cm以上の大径木は,A.花山地区で17本(全本数204本の中に占める比率8.3%),うちヤクスギは11本(同じく5.4%),B.白谷地区では2本(全本数99本に対し2.0%),うちヤクスギ1本(1.0%)であった.空中写真によるヤクスギの判読測定は,本研究に使用した空中写真が1963年10月および1969年5月に撮影された古い写真だったこと,およびパンクロマチックフィルムによる白黒写真のため,スギとツガその他の針葉樹との間で樹冠の形状や色調濃淡による樹種間の差異等がはっきりしなかったため,その識別や測定はできなかった.しかし胸高直径(DBH)と樹冠直径(CD)の関係はスギとツガでは明らかな特長が認められた.今後,樹種本来の有する波長差や反射光量等の特性を明確に反応するフィルム(赤外フィルム,赤外カラーフィルム,フォールスカラーフィルム,デジタルカラーフィルム等)の試用による検討とチェックが必要である

The Examination of the Conformity between Actual Volume and the Volume Presented in Volume Table

In the forest inventory for stand growing stock estimation, stand increment prediction and other purposes, the precision of estimation and prediction and the appropriateness of the management planning made on the basis of the mentioned estimated and predicted values, are largely affected by the fitness of applied volume table to the condition of observed stand. In order to prepared volume tables which are fitting well to the condition of stand in a given region, in a given district or in a given forest area, a great numbers of local volume tables are needed. However, for the preparation of volume table, enormous data are needed and many time, cost and effort must be spent for the data collection and analysis both. Therefore, volume tables are, in general, prepared for a large region. Accordingly, in the application of volume tables the fitness of table to the condition of a given stand is necessary to be tested in advance. This study aims to examine the appropriateness of volume tables for Pinus elliottii and Pinus patulu. 40 of Pinus elliottii (with bark and without bark volumes) from Águas de Santa Bárbara state forest in São Paulo region and 42 trees of Pinus elliottii and 27 trees of Pinus patula (both with bark volumes) from Campos do Jordão state forest has been selected and measured. The conformity of measured volume to the corresponding values presented in volume table are tested on the basis of t-test. The results are presented in Table 5 and Figs. 4-6. The values those presented in Tabela-1 and Tabela-2 which are corresponding to Pinus elliottii in Águas de Santa Barbara state forest, and in Tabela-2 and Tabela-43 which are corresponding to Pinus elliottii and Pinus patula of Campos do Jordão state forest, respectively, are significantly different from those shown by Volume Table-A and Volume Table-B. This means that the measurement volumes do not fit well to those values presented in volume tables. Therefore, the regression equations those express the relationships between actual volumes and the values in volume table were analyzed. The results are presented in Table 6 and the values adjusted on the basis of the above mentioned relationships are given in Table 7. By this method, the values in a not appropriate volume table is adjusted and made to be closely agree to the actual volume of observed stand.森林蓄積の推定や林分生長量の予測,その他の森林調査を行なう場合,使用する材積表(立木幹材積表)がその林分に適合しているかどうかは,その推定精度や予測結果等に大きく影響する.材積表は地方や地域,地区等の小範囲を対象に調製された,いわゆるlocal volume tableが適合性は高い.しかし材積表は膨大なデータの収集とその分析検討および重回帰式による材積式の計算や材積表の調製等,多くの時間や労力,経費等を必要とする.そのため一般には材積表は広い範囲を対象に調製されるケースが多い.したがって使用する材積表はその適合度を事前に検定しておくことが望ましい.本研究はサンパウロ州Águas de Santa Bárbara州有林のPinus elliottii 40本(with bark, without bark)およびCampos do Jordão州有林のPinus elliottii 42本,Pinus patula 27本(何れもwith bark)を対象に標本木の実測材積を求め,これとそれぞれにおいて使用される材積表材積との対応による適合度の検定をt検定により試みた.その結果はTable5およびFig.4-Fig.6に示すとおりとなった.すなわちÁguas de Santa Bárbara州有林におけるPinus elliottiiのTabela-1,Tabela-2,およびCampos do Jordão州有林におけるPinus elliottiiのTabela-2,Pinus patulaのTabela-43,材積表-A,材積表-Bで有意差を示し,材積表材積は実測材積と適合しなかった.そのためTable6に示すとおり実測材積と材積表材積の回帰式を計算し,これにもとづいてTable7のように材積表材積の修正表を示した.これにより適合しなかった材積表材積は調査対象林分の材積の真値に近似的に修正されることになる

The Estimation of Tree Numbers of Sugi (Cryptomeria japonica) in Yakushima

Yakushima is an island located at about 130 km to the south of Kagoshima city. Total area and circumference of the island are equal to 500.56 km^2 and 100 km, respectively. The island has the shape which is similar to a circle. The distance between north and south capes of the island is about 28 km, while the distance between west and east capes of the island is about 24 km. Besides Mt. Miyanoura, the highest in Kyushu region, with the elevation of 1,935 m, there are also more than 30 mountains with the elevation of 1,000 m and avove. In relation to the above mentioned, 45,461 ha or 90.8% of total island area is covered by mountain forest. This is consisting of National Forest, Communual Forest and Private Forest with the area of 38,600 ha (84.9%), 1.705 ha (3.8%) and 5,156 ha (11.3%), respectively. The main species in the National Forest is Sugi (Cryptomeria japonica) with the ages of more than 1000 years and normally called as “Yakusugi”. Diameter (DEW) of the Yakusugi is larger than 120 cm. Meanwhile, in Yakushima, trees with DBH smaller than 120 cm are normally called as “Kosugi”. As the standing stock of Yakusugi is gradually decreases its protection and cultural treatment has been becoming a serious problem in the recent time. This study intended to obtain the basic data for the protection and cultural treatment of Yakusugi and to clarify the effective method for the estimation of the number of tree of Yakusugi. In relation to this purpose, an investigation by strip sampling has been conducted in Hanayama district, Shimo-Yaku Forest Region and Shiratani district, Kami-Yaku Forest Region. The investigated forest area are 175.13 ha in Hanayama district and 138.96 ha in Shiratani district. As the result, it was obtained that total number of Sugi trees in Hanayama district, with the significant level of 5%, is equal to 19947.3f4587.5 stems (The total number for Hinoki, Tsuga and Momi trees are equal to 875.7f716.4 stems, 2723.8±1317.2 stems and 389.7±468.5 stems, respectively). In Shiratani district, it was found that the total number of Sugi trees is equal to 18103.0±12278.2 stems (The total number Tsuga and Momi trees are equal to 1827.3±3117.2 stems and 548.9f625.7 stems, respectively). The larger-size trees with DBH of 120 cm and above, was found to equal to 17 stems and 11 stems of them are Yakusugi (these are covering 8.3% and 5.4% of total number of 204 stems, respectively). In Shiratani district, it was found that larger-size trees are amount to 2 stems and 1 stem of them is Yakusugi (these are covering 2% and 1% of total number of 99 stems, respectively). The interpretation of standing stock of Yakusugi by aerial photograph has not presented the expected result. This is because the aerial photograph esed in this study are old panchromatic photos taken in October 1963 and May 1969. And therefore, the different of crown form, tone and contrastly between Sugi and Tsuga or another needle-leave trees, was not clearly identified. However, the relations between DBH and crown diameter (CD) for Sugi and Tsuga present the different significantly. In the future, it is necessary to conduct the investigation by using the film which be able to present the clearly different characteristics of multispectral and reflection of different species, such as infrared film, infrared color film, false color film, digital color film, etc.屋久島は鹿児島市の南約130kmの洋上に位置し,東西約28km,南北24km,周囲100kmのほぼ円形の島で,面積500.56km^2を有する.ここには九州で一番高い1935mの宮之浦岳をはじめ,1,000m以上の山岳が30以上も連座している.そのため全島の90.8%に及ぶ45461haが山林となっている.地形は急峻で,起伏度もきわめて激しい.そのうち38600ha(84.9%)が国有林,1705ha(3.8%)が公有林,5156ha(11.3%)が私有林となっている.ヤクスギは主として国有林の中に生立し分布している.ヤクスギは樹齢1000年以上のものをいう.胸高直径(DBH)では120cm以上がその対象となっている.それ以下のものは屋久島ではコスギと称している.そのヤクスギが年々減少してきているため,現在,その保護と育成が問題となっている.本研究はヤクスギの保護と育成のための基礎資料をうること,および効率的な本数推定の方法を究明することを目的として,ヤクスギ,コスギを含むすべてのスギの立木本数の推定を,A.下屋久営林署管内花山地区(面積175.13ha),およびB.上屋久営林署管内白谷地区(面積138.96ha)を対象にしてストリップ調査により行なった.その結果,危険率5%(t_<.05>)により,A.花山地区で175.13ha当り19947.3±4587.5本(他にヒノキ875.7±716.4本,ツガ2723.3±1317.2本,モミ389.7±468.5本)となった.B.白谷地区では138.96ha当り18103.0±12278.2本(他にツガ1827.3±3117.2本,モミ548.9±625.7本)となった.なお,この中でDBH120cm以上の大径木は,A.花山地区で17本(全本数204本の中に占める比率8.3%),うちヤクスギは11本(同じく5.4%),B.白谷地区では2本(全本数99本に対し2.0%),うちヤクスギ1本(1.0%)であった.空中写真によるヤクスギの判読測定は,本研究に使用した空中写真が1963年10月および1969年5月に撮影された古い写真だったこと,およびパンクロマチックフィルムによる白黒写真のため,スギとツガその他の針葉樹との間で樹冠の形状や色調濃淡による樹種間の差異等がはっきりしなかったため,その識別や測定はできなかった.しかし胸高直径(DBH)と樹冠直径(CD)の関係はスギとツガでは明らかな特長が認められた.今後,樹種本来の有する波長差や反射光量等の特性を明確に反応するフィルム(赤外フィルム,赤外カラーフィルム,フォールスカラーフィルム,デジタルカラーフィルム等)の試用による検討とチェックが必要である