Ten-year longitudinal investigation of astigmatism: The Yamagata Study (Funagata).

Despite numerous investigations into ocular or corneal astigmatism, the dynamic nature of astigmatism remains poorly understood. To reveal potential associations between age and astigmatism, 264 Japanese participants who underwent systemic and ophthalmological examinations in Funagata Town (Yamagata Prefecture, Japan) were evaluated over a 10-year period. Astigmatism was evaluated with regard to the cylinder power, cylinder axis, and vector analyses. Whereas the refractive cylinders showed age-related increases in patients in their 40s to 60s, the corneal cylinders did not change over 10 years. Nevertheless, cylindrical axis of the cornea demonstrated a continuous shift toward against-the-rule (ATR) astigmatism. Vector analyses revealed that the astigmatic shift toward ATR progressed continually after patients reached their 40s, although the shift did not accelerate with age. These novel insights may pave the way for the development of potential strategies for vision correction, including refractive surgeries, and vision-quality maintenance in the elderly.

Age-Related Changes in Astigmatism and Potential Causes.

Astigmatism causes deterioration of the retinal image and affects vision quality. Maintenance and improvement of visual function requires an understanding of the prevalence, age-related changes, and mechanisms of astigmatism. In this article, we discuss the findings of studies that investigated astigmatism. Some of these studies showed that the prevalence of high degrees of astigmatism in childhood typically decreases with emmetropization. With-the-rule astigmatism occurs most commonly in young adults. With age, the prevalence of astigmatism increases, and the axis shifts from a predominance of with-the-rule astigmatism to a predominance of against-the-rule astigmatism. This age-related change is caused by alterations in corneal curvature. Although the cause of this change is not fully understood, alterations in the position and tension of the eyelid, corneal stromal collagen fibrils, Descemet membrane, and extraocular muscles may influence the shape of the cornea. Furthermore, genetic factors may contribute to the development of astigmatism. Technological advances in ophthalmology are expected to improve our understanding of the etiology of astigmatism and enable the maintenance of quality of vision.

Nano Precipitation and Hardening of Die-Quenched 6061 Aluminum Alloy.

Die quenching is applied to an age-hardenable aluminium alloys to obtain super-saturated solid solution. The application is advantageous because it can reduce number of manufacturing processes, and may increase strength by strain aging. If die quenching is realized in forging as well as sheet forming, it may widen industrial applicability further. In this study, Al-Mg-Si alloy AA6061 8 mm-thick billets were reduced 50% in height without cracks by die-quench forging. Supersaturated solid solution was successfully obtained. The die-quenched specimen shows higher hardness with nano precipitates at shorter aging time than the conventional water-quenched specimen.

[Ruptured giant fusiform anterior cerebral artery aneurysm treated by proximal clipping with a3-a3 bypass:case report].

Giant fusiform aneurysm of the anterior cerebral artery (ACA) involving the anterior communicating artery (AcomA) is difficult to treat, and its postoperative course is not well known. We treated a patient with subarachnoid hemorrhage (SAH) due to rupture of a giant fusiform aneurysm of the ACA involving the AcomA. Here we describe its treatment and postoperative course, and review the literature regarding ACA involving an AcomA aneurysm that was treated with bypass surgery. A 65-year-old man presented with sudden onset of headache and vomiting. Computed tomography (CT) revealed SAH due to rupture of a giant fusiform ACA involving an AcomA aneurysm. He was admitted to the local neurosurgical unit 5 days after symptom onset. After waiting for vasospasm to resolve, he was transferred to our hospital. Three-dimensional CT demonstrated giant fusiform dilatation (25mm in diameter) of the left ACA (A1-A2), and the AcomA was involved. The perforating branches around the aneurysm were not identified. We performed proximal clipping with A3-A3 bypass for protection of reversal flow to the perforating branches of the left ACA. Postoperative magnetic resonance imaging showed a small infarction in part of the left caudate nucleus and the fornix. Cerebral angiogram revealed complete obliteration of the aneurysm. The patient did not experience palsy or aphasia, but he suffered from transient disturbance of frontal lobe function. A few months later, his cognitive function had recovered, and he was able to resume his normal daily life. Although clinicians should monitor for the development of postoperative neurological symptoms, including cognitive dysfunction proximal clipping with A3-A3 bypass was an effective and reliable treatment for ruptured giant fusiform ACA involving an AcomA aneurysm.

Fabrication and evaluation of nanostructure Al-SiCp composite by accumulative roll-bonding.

A nanostructured Al/SiCp composite was fabricated by accumulative roll bonding (ARB) process. The amount of SiC particles introduced into aluminum sheet by one cycle ARB was 0.22 mg/cm2. Increment of the number of ARB cycles increased the amount of SiC particles and enhanced the homogeneity of the distribution of SiC particles. Microstructural change in aluminum matrix with proceeding of the ARB was very similar to that of the ARB-processed unreinforced aluminum; showing a dislocation cell and/or sub-grain structure in samples of lower ARB cycles and ultrafine grained structure in samples of higher ARB cycles. The variation of tensile strength with the ARB was also very similar to that of unreinforced aluminum. However, the effect of strengthening by the ARB was higher in the Al/SiCp composite than in unreinforced aluminum due to an existence of the SiC particles and the formation of finer grains.

Nano-porous layer on steel surface as lubricant carrier.

In cold forging of steels, metal soap on zinc-phosphate coating is excellent lubrication system. However, the system is not only less productive, but produces hazardous wastes. In this study, an alternative lubrication system using surface porous layer is proposed. Surface oxide on low carbon steel turns into porous layer by chemical reduction using hydrogen. It is found that liquid lubricant decreases the friction coefficient in compression greatly. The porous surface enhances the decrease, especially in the cases of heavy deformation.

Efficacy of 3-year psychiatric daycare treatment in patients with schizophrenia.

The present study investigated the efficacy of a 3-year psychiatric daycare (DC) program with regard to psychiatric symptoms and difficulties with daily living experienced by patients with schizophrenia. The subjects were 28 patients who met the diagnostic criteria from the 4th edition of the Diagnostic and Statistical Manual for schizophrenia and continued DC treatment for 3 years. The present study assessed participants at two points: at the start of DC and after 3 years, by evaluating socioeconomic factors and Brief Psychiatric Rating Scale (BPRS) scores. In addition, in order to measure difficulties with daily living, the Life Assessment Scale for the Mentally Ill (LASMI) and the Etoh Daycare Assessment Scale (ETODAS) developed at the Etoh Hospital, were used. Results indicated that no significant changes in socioeconomic factors or BPRS scores occurred during the 3-year period of DC treatment. However, over this period, mean scores (+/- standard deviation [SD]) for LASMI subcategories decreased from 1.6 +/- 0.8 points to 0.9 +/- 0.7 for daily living and from 1.7 +/- 0.8 to 1.2 +/- 0.7 for interpersonal relations, indicating significant improvement (P < 0.05). In addition, mean scores (+/-SD) for the ETODAS subcategories increased from 3.4 +/- 0.8 to 4.1 +/- 0.8 for expressiveness, from 3.3 +/- 0.9 to 4.0 +/- 0.8 for communication, from 3.1 +/- 0.6 to 3.6 +/- 1.0 for initiative within a group, and from 3.4 +/- 0.5 to 3.8 +/- 0.7 for cooperation in work activities, indicating significant improvement (P < 0.05). The present study suggests that DC can enable patients with schizophrenia to maintain their condition without worsening the psychiatric symptoms, and to improve their daily living skills, social skills in human relations, and work skills.