Napping after complex motor learning enhances juggling performance

AbstractThe present study examined whether a nap after complex motor learning enhanced the following day's physical performance. Eighteen volunteers met the inclusion criteria and were assigned to either a nap (n=9; men=5; mean age=21.0±1.5) or no-nap group (n=9; men=5; mean age=21.9±0.3). Participants practiced juggling in the morning and were tested immediately afterwards. Participants of the nap group were given a 70-minute nap opportunity after juggling practice, while the no-nap group stayed awake. Juggling performance was then tested in the evening (retest-1) and the next morning (retest-2). Two-way analysis of variance (group: nap, no-nap×time: test, retest-1, retest-2) found there was a significant effect of test time and a significant group×time interaction. The juggling performance of both groups improved from test to retest-1, respectively. However, the juggling performance level of the nap group was higher than that of the no-nap group at the retest-1. As predicted, a nap promptly after learning motor skills was associated with subsequently improved performance. Moreover, the juggling performance of the nap group showed additional significant improvements in the retest-2. In the no-nap group, however, there were no significant improvements in the juggling performance after nocturnal sleep. These results demonstrate that the benefits of a nap following learning were further enhanced after nocturnal sleep. The present results may provide justification for introducing nap periods into daily athletic training as an active method to improve performance

Investigation on microstructure and mechanical properties of FA/GGBS -based geopolymer after exposure at elevated temperature

Fly ash (FA) and ground granulated blast -furnace slag (GGBS) are industrial wastes and have been widely utilized as construction material due to the environmental impacts. The use of these by-products is not only for the sustainable construction but also for reducing the emission of CO2 due to the use of Portland cement. This study presents the microstructure and mechanical properties of geopolymer paste made from different ratios of low -calcium FA and GGBS after exposure at elevated temperature (500- 950oC). Compressive strength tests for both heated and unheated cylindrical specimens (using 50 mm x 100 mm mold) after the age of 28 days have been carried out. The results showed that the compressive strength of unheated specimens is increasing with increasing amount of GGBS in the mixes (up to 84 MPa). However, exposure at high temperature caused dehydration of water inside the specimen, resulting in strength loss. It was also found that exposure at 500oC caused a shrinkage, while a thermal expansion event was observed to occur at approximately 750oC. Moreover, scanning electron microscopy (SEM), X-ray diffraction (XRD), and mercury intrusion porosimetry (MIP) methods have been used to investigate the microstructure, phase composition, and pore distribution, respectively

Effect of Sodium Sulfate Activator on Compressive Strength and Hydration of Fly-Ash Cement Pastes

In the study, the effect of 4% sodium sulfate (Na2SO4) as an activator on cement pastes with 0%, 20%, and 40% fly-ash replacements and a low water-to-cementitious materials ratio of 0.30 was investigated. The investigation was conducted to evaluate the effectiveness of the technique for the utilization of fly ash in developing sustainable concrete. The use of Na2SO4 decreased setting times of the fresh pastes and increased compressive strength of the hardened pastes up to 28 days irrespective of fly-ash replacement. The use decreased Ca(OH)2 content in the hardened pastes irrespective of fly-ash replacement. Meanwhile, it increased Ca(OH)2 consumption by the pozzolanic reaction of fly ash and content of calcium silicate and aluminate hydrates in the hardened fly-ash–cement pastes. Consequently, the use of Na2SO4 negatively affected cement hydration in the hardened cement pastes without fly ash, while it accelerated ettringite formation and pozzolanic reaction of fly ash in the hardened pastes

Exploring Learning Problems of Filipino Nurse Candidates Working in Japan: Based on the Results of a Practice National Board Examination of Japan Given in English

This article investigates the status of the education and training of Filipino nurse candidates who have been working in Japan under the Japan-Philippine Economic Partnership Agreement (JPEPA). A survey was conducted among Filipino nurse candidates, using a practice examination based on the English version of Japan’s National Board Examination for Registered Nurses in 2009. Categorized by area, the mean correct answer rate for nursing-related questions ranged between 61% and 73%; the rate for questions concerning basic knowledge of body functions and diseases ranged between 55% and 57%. There was a large gap in terms of the results of the examination between those who had previously seen the exam questions and those who had never seen them. While 57.1% of those who had previously seen the questions satisfied the acceptance criteria, only 23.7%of those who had never viewed the test satisfied it. Based on these results, the factors which serve as obstacles that Filipino nurse candidates encounter in passing the national examination include not only difficulties in acquiring Japanese proficiency but also differences between Japan and the Philippines in respect to the nursing education curriculum and basic nursing policies

Exploring Learning Problems of Filipino Nurse Candidates Working in Japan: Based on the Results of a Practice National Board Examination of Japan Given in English

This article investigates the status of the education and training of Filipino nurse candidates who have been working in Japan under the Japan-Philippine Economic Partnership Agreement (JPEPA). A survey was conducted among Filipino nurse candidates, using a practice examination based on the English version of Japan’s National Board Examination for Registered Nurses in 2009. Categorized by area, the mean correct answer rate for nursing-related questions ranged between 61% and 73%; the rate for questions concerning basic knowledge of body functions and diseases ranged between 55% and 57%. There was a large gap in terms of the results of the examination between those who had previously seen the exam questions and those who had never seen them. While 57.1% of those who had previously seen the questions satisfied the acceptance criteria, only 23.7%of those who had never viewed the test satisfied it. Based on these results, the factors which serve as obstacles that Filipino nurse candidates encounter in passing the national examination include not only difficulties in acquiring Japanese proficiency but also differences between Japan and the Philippines in respect to the nursing education curriculum and basic nursing policies

An investigation on moisture and water absorption in cement paste with electrical resistance method

Moisture in concrete is one of main factors related to degradation and deterioration of concrete structure, and there are various moisture transport phenomena in concrete such as drying and absorbing. There are a lot of previous studies on the drying process of concrete to clarify the mechanisms of creep as well as shrinkage. However, few studies have been reported on the process of water absorption and moisture absorption although carbonation and chloride attack are strongly related to moisture and water absorbing. It is necessary to investigate moisture transfer in concrete in detail. This study investigated the moisture transfer in moisture and water absorbing processes in cement paste by using electrical resistance method to understand how moisture and water transfer into concrete. Cement paste specimens with water-to-cement ratios (W/Cs) of 0.35 and 0.55 were prepared in this study. Stainless steel rods of 0.9 mm in diameter were arranged at an interval of 4 mm in the specimen for measuring the electrical resistance. The specimens for moisture and water absorbing test were cured in water at 20 ºC for 28 days and stored at 20 ºC and a relative humidity of 0% and 70% as reference and the national average of the annual average relative humidity in Japan, respectively. The electrical resistances were measured through the stainless-steel rods and converted to electrical resistivity. The calibration test was also conducted to obtain the relationship between the electrical resistivity and the internal relative humidity (IRH), which was used to know IRH in cement paste specimen. As a result, the rate of moisture transfer in the specimen at initial internal relative humidity (IIRH) of 0% was higher than that at IIRH of 70%. Additionally, the rate of moisture transfer in the specimen at any IIRH depends on the total pore volume in the specimen

A Rat Model of Mild Intrauterine Hypoperfusion with Microcoil Stenosis

International audienceIntrauterine hypoperfusion/ischemia is one of the major causes of intrauterine/fetal growth restriction, preterm birth, and low birth weight. Most studies of this phenomenon have been performed in either models with severe intrauterine ischemia or models with gradient degree of intrauterine hypoperfusion. No study has been performed in a model on uniform mild intrauterine hypoperfusion (MIUH). Two models have been used for studies of MIUH: a model based on suture ligation of either side of the arterial arcade formed with the uterine and ovarian arteries, and a transient model based on clipping the bilateral ovarian arteries and aorta having patency. Those two rodent models of MIUH have some limitations, e.g., not all fetuses are subjected to MIUH, depending on their position in the uterine horn. In our MIUH model, all fetuses are subjected to a comparable level of intrauterine hypoperfusion. MIUH was achieved by mild stenosis of all four arteries feeding the uterus, i.e., the bilateral uterine and ovarian arteries. Arterial stenosis was induced by metal microcoils wrapped around the feeding arteries. Producing arterial stenosis with microcoils allowed us to control, optimize, and reproduce decreased blood flow with very little inter-animal variability and a low mortality rate, thus enabling accurate evaluation. When microcoils with an inner diameter of 0.24 mm were used, the blood flow in both the placenta and fetus was mildly decreased (approximately 30% from the pre-stenosis level in the placenta). The offspring of our MIUH model clearly demonstrates long-lasting alterations in neurological, neuroanatomical and behavioral test results

Contribution of fly ash to mortar strength development under steam and internal curing

The purpose of this study is to quantitatively evaluate the effects of steam curing and internal curing on contribution of fly ash to strength development of mortar by using cementing efficiency factor (k-value) that represents strength development performance as a binder of fly ash. In addition, the pozzolanic reaction of fly ash was evaluated from the viewpoint of calcium hydroxide consumption by using thermogravimetry and differential thermal analysis as well as the degree of fly ash reaction by using selective dissolution method. The result indicated that steam curing improved early compressive strength and internal curing improved compressive strength and k-value at all ages. Also, a linearrelationship between the degree of fly ash reaction and the k-value was shown regardless of the age and the replacement ratio of fly ash

Risk of Gynecologic Cancer as Second versus First Primary Cancer in Japan

This study aimed to determine whether the risk conferred by gynecologic cancer (GC) as second primary cancer (SPC) differs from that associated with GC as first primary cancer (FPC). We investigated the correlations between FPC/SPC and the characteristics and prognoses of 1,645 GC patients (701 with cervical cancer [CC], 641 with endometrial cancer [EM], and 303 with ovarian cancer [OV]). The χ2 test and the Kaplan–Meier method were used to determine whether FPC/SPC and the characteristics and prognoses of GC patients. Of the SPC patients, 26 (3.7%) had CC, 53 (8.3%) had EM, and 31 (10.2%) had OV. The most common previous cancer type in SPC of GC patients was breast cancer, which was observed in 13 patients (50.0%) with CC, 23 (43.4%) with EM, and 16 (51.6%) with OV. In all patients with CC, EM, and OV as SPC, the stage was significantly associated with recurrence. There were no significant differences in the morbidity or mortality of CC, EM, or OV patients between those with FPC and those with SPC. The risk of SPC development in GC patients varied, ranging from 3.5% (CC) to 10.3% (OV) of patients