近視学童における部分的干渉測定法を用いた眼軸長測定について：測定のリピータビリティと屈折要素との比較

PURPOSE: To evaluate the test-retest repeatability of axial length (AL) measurements made with the IOLMaster in children with a wide range of myopic refractive errors, and to clarify the relationship between the AL and other refractive components. METHODS: The subjects were 95 children (mean age +/- SD, 10.8 +/- 1.3 years; range, 7-13 years; mean refractive error; -4.37 +/- 1.43 D; range, -1.50 to -8.19 D) who participated in a myopia-control trial. The AL of the right eye was measured three times using an IOLMaster, and the mean value was regarded as the representative measurement. After 5 min, the measurement was performed again, and the repeatability was evaluated by analyzing the distribution of differences between the two measurements. The relationships between the AL and age, cycloplegic autorefraction (RE), and corneal radius of curvature (CR) were also examined. RESULTS: The repeatability of the IOLMaster measurements was +/-0.05 mm (corresponding to a refractive error of +/-0.12 D) and was not affected by age or RE. AL was negatively correlated with RE (RE = -0.68 x AL + 12.74, r = -0.37) and positively correlated with CR (CR = 0.21 x AL + 2.53, r = 0.69). The highest correlation was found between the ratio of AL to CR and RE (AL/CR = -0.04 x RE + 3.08, r = -0.76). No association was observed between age and AL, nor between CR and RE. CONCLUSIONS: The IOLMaster provides high repeatability in AL measurement in myopic children. The associations between AL and each refractive component found in this study were consistent with those in previous studies that used the ultrasound A-mode method, except for slightly higher AL/CR ratios in our study

Autologous Internal Limiting Membrane Transplants Successfully Close a Large Parafoveal Retinal Hole

　Parafoveal retinal holes (PRHs) are one of the complications that can occur after internal limiting membrane (ILM) peeling during macular surgery. Here we describe a patient in whom an exceptionally large PRH (1,069-μm dia.) was successfully closed by repeated autologous ILM transplantation

The space of non-extendable quasimorphisms

For a pair $(G,N)$ of a group $G$ and its normal subgroup $N$, we consider the space of quasimorphisms and quasi-cocycles on $N$ non-extendable to $G$. To treat this space, we establish the five-term exact sequence of cohomology relative to the bounded subcomplex. As its application, we study the spaces associated with the kernel of the (volume) flux homomorphism, the IA-automorphism group of a free group, and certain normal subgroups of Gromov hyperbolic groups. Furthermore, we employ this space to prove that the stable commutator length is equivalent to the stable mixed commutator length for certain pairs of a group and its normal subgroup.Comment: 58 pages, 1 figure. Major revision. Theorem 1.12 in v3 has been generalized to Theorem 1.2 in the current version: this new theorem treats hyperbolic mapping tori in general cases, and it serves as a leading application of our main theore

Coarse group theoretic study on stable mixed commutator length

Let $G$ be a group and $N$ a normal subgroup of $G$. We study the large scale behavior, not the exact values themselves, of the stable mixed commutator length $scl_{G,N}$ on the mixed commutator subgroup $[G,N]$; when $N=G$, $scl_{G,N}$ equals the stable commutator length $scl_G$ on the commutator subgroup $[G,G]$. For this purpose, we regard $scl_{G,N}$ not only as a function from $[G,N]$ to $\mathbb{R}_{\geq 0}$, but as a bi-invariant metric function $d^+_{scl_{G,N}}$ from $[G,N]\times [G,N]$ to $\mathbb{R}_{\geq 0}$. Our main focus is coarse group theoretic structures of $([G,N],d^+_{scl_{G,N}})$. Our preliminary result (the absolute version) connects, via the Bavard duality, $([G,N],d^+_{scl_{G,N}})$ and the quotient vector space of the space of $G$-invariant quasimorphisms on $N$ over one of such homomorphisms. In particular, we prove that the dimension of this vector space equals the asymptotic dimension of $([G,N],d^+_{scl_{G,N}})$. Our main result is the comparative version: we connect the coarse kernel, formulated by Leitner and Vigolo, of the coarse homomorphism $\iota_{G,N}\colon ([G,N],d^+_{scl_{G,N}})\to ([G,N],d^+_{scl_{G}})$; $y\mapsto y$, and a certain quotient vector space $W(G,N)$ of the space of invariant quasimorphisms. Assume that $N=[G,G]$ and that $W(G,N)$ is finite dimensional with dimension $\ell$. Then we prove that the coarse kernel of $\iota_{G,N}$ is isomorphic to $\mathbb{Z}^{\ell}$ as a coarse group. In contrast to the absolute version, the space $W(G,N)$ is finite dimensional in many cases, including all $(G,N)$ with finitely generated $G$ and nilpotent $G/N$. As an application of our result, given a group homomorphism $\varphi\colon G\to H$ between finitely generated groups, we define an $\mathbb{R}$-linear map `inside' the groups, which is dual to the naturally defined $\mathbb{R}$-linear map from $W(H,[H,H])$ to $W(G,[G,G])$ induced by $\varphi$.Comment: 69 pages, no figure. Minor revision (v2): some symbols change

Survey on invariant quasimorphisms and stable mixed commutator length

In this survey, we review the history and recent developments of invariant quasimorphisms and stable mixed commutator length.Comment: 26 pages, 1 figure; minor revisio

Scanning Josephson Tunneling Microscopy of Single Crystal Bi\u3csub\u3e2\u3c/sub\u3eSr\u3csub\u3e2\u3c/sub\u3eCaCu\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e8+δ\u3c/sub\u3e with a Conventional Superconducting Tip

We have performed both Josephson and quasiparticle tunneling in vacuum tunnel junctions formed between a conventional superconducting scanning tunneling microscope tip and overdoped Bi2Sr2CaCu2O8+δ single crystals. A Josephson current is observed with a peak centered at a small finite voltage due to the thermal-fluctuation-dominated superconducting phase dynamics. Josephson measurements at different surface locations yield local values for the Josephson IcRn product. Corresponding energy gap measurements were also performed and a surprising inverse correlation was observed between the local IcRn product and the local energy gap

The Effect of a Portable Electrical Muscle Stimulation Device at Home on Muscle Strength and Activation Patterns in Locomotive Syndrome Patients: A Randomized Control Trial

The aim of the present study was to quantify the effect of electrical muscle stimulation (EMS) intervention using a portable device on muscle strength and activation patterns in locomotive syndrome. Nineteen women were randomly assigned to the intervention group (n = 10; age = 71–82 years) and control group (n = 9; age = 70–84 years). Participants in the intervention group used a portable EMS device to stimulate the bilateral quadriceps muscles for 8 weeks (23 min/5 days/week). To understand the effects of EMS, the following measurements were made at baseline, 8 weeks, and 12 weeks: locomotive syndrome assessment score, knee extensor strength, vastus lateralis muscle activation patterns during a maximal isometric knee extension contraction using multi-channel surface electromyography, and muscle thickness. The locomotive syndrome assessment, muscle strength, muscle thickness, and muscle activity patterns in the intervention group were significantly different to control after 8 weeks (p \u3c 0.05). However, these results were not sustained at 12 weeks. EMS increased locomotor assessment scores, which were accompanied by enhanced muscle strength, increased muscle thickness, and changes in muscle activation patterns in locomotive syndrome patients. These results suggest that EMS is potentially useful for improving muscle neural activation and force output in locomotive syndrome