Mito-shi, Japan
Mito-shi, Japan

Tokiwa University is a private university in Mito, Ibaraki, Japan, established in 1983. The predecessor of the school was founded in 1909.California State University, Fresno & California State University, Northridge's Japanese Department has had an active international student exchange program with this university since 2004. Wikipedia.

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Omoe K.,Iwate University | Hu D.-L.,Kitasato University | Ono H.K.,Iwate University | Ono H.K.,Hirosaki University | And 6 more authors.
Infection and Immunity | Year: 2013

Staphylococcal enterotoxins (SEs) are a common causative agent of food poisoning. Recently, many new SE-like (SEl) toxins have been reported, although the role of SEls in food poisoning remains unclear. In this study, the emetic potentials of SElK, SElL, SElM, SElN, SElO, SElP, and SElQ were assessed using a monkey-feeding assay. All the SEls that were tested induced emetic reactions in monkeys at a dose of 100 μg/kg, although the numbers of affected monkeys were significantly smaller than the numbers that were affected after consuming SEA or SEB. This result suggests that these new SEs may play some role in staphylococcal food poisoning. ©2013, American Society for Microbiology.

Hamatani R.,Tokyo Women's Medical University | Otsu M.,Tokyo Women's Medical University | Otsu M.,Tokiwa University | Chikamoto H.,Tokyo Women's Medical University | And 2 more authors.
Clinical and Experimental Nephrology | Year: 2014

Background: Hyperhomocysteinemia (hyper-Hcy) is an important and reversible cardiovascular disease risk factor. We examined the prevalence of hyper-Hcy, plasma folate levels, and dietary folate intake in adolescents and young adults who had undergone kidney transplantation during childhood to assess the necessity for managing dietary folate. Methods: This cross-sectional study was performed in 89 kidney transplant recipients (age at kidney transplantation: 12.6 ± 4.1 years; age during study: 21.2 ± 5.5 years). Hyper-Hcy and plasma folate deficiency were defined as plasma homocysteine (Hcy) >15 nmol/ml and plasma folate <3.0 ng/ml, respectively. Results: Of the patients, 60 (67.4 %) had hyper-Hcy and 14 (15.7 %) had plasma folate deficiency. Plasma homocysteine levels correlated negatively with estimated glomerular filtration rate (eGFR; r = -0.565, p < 0.01) and plasma folate levels (r = -0.434, p < 0.01). For determinants of plasma homocysteine levels, a priori selected variables included kind of calcineurin inhibitor, age at kidney transplantation, pretransplant duration of dialysis, time since transplantation, age at examination, eGFR, and plasma folate. Stepwise multiple linear regression analysis revealed eGFR and plasma folate levels as significant independent variables influencing plasma homocysteine levels. Dietary folate intake in 11 of 16 patients (66.8 %) with eGFR ≥60 ml/min/1.73 m2 was below the recommended dietary allowance for Japanese. Conclusions: The prevalence of hyper-Hcy and plasma folate deficiency, as well as the low dietary folate intake, suggest that dietary management of folate is necessary for adolescents and young adults who have undergone kidney transplantation during childhood. © 2013 Japanese Society of Nephrology.

PubMed | Tokiwa University and Kujukushima Aquarium Umi Kirara
Type: | Journal: Behavioural processes | Year: 2016

Dolphins exhibit prosocial behavior across several different contexts. However, only a few experimental studies have investigated the psychological mechanisms underlying this behavior. In this study, we investigated the mechanisms underlying prosociality in bottlenose dolphins (Tursiops truncatus). In the experiments, water shower devices, developed as environmental enrichment items, were used. Two paradigms were used to measure prosociality. The first was the prosocial choice task, involving the subject typically being offered one choice between two options. The first option provided a reward (take a shower) to both the subject and partner (prosocial choice). The second option provided a reward only to the subject (selfish choice). The second paradigm was the giving assistance task, involving the subject being provided a choice between providing instrumental help to the partner (prosocial choice) or doing nothing. It was observed that the subjects chose the prosocial choices in both paradigms. In these experiments, prosocial choices were spontaneously taken without requests from the partners. These results indicated that the dolphins show preference for other-regarding behavior.

Iwata T.,The Institute of Statistical Mathematics of Tokyo | Iwata T.,Tokiwa University
Pure and Applied Geophysics | Year: 2016

The model based on rate- and state-dependent friction law reproduces the temporal decay of an aftershock sequence with the p value of the Omori–Utsu law equal to 1, if we simply assume a constant stress rate over time. However, because p values vary in real aftershock sequences, this model requires some modification. This study examined the effect of secondary aftershocks on the variety of the p value. A large aftershock causes a stepwise stress increase in the aftershock area, and the expected seismicity rate derived from the friction law also increases abruptly. These multiple increases in the seismicity rate during its decay following a mainshock could cause variation in the apparent p value. In this study, a model incorporating this idea is applied to two aftershock sequences observed in Japan and is shown to substantially modify the modeling of aftershock activity. © 2015, Springer Basel.

Inamura Y.,Niigata University of Health and Welfare | Sagae T.,Tokiwa University | Nakamachi K.,Jiunndo Naika Hospital | Murayama N.,Niigata University of Health and Welfare
International Journal of Psychiatry in Medicine | Year: 2012

Objective: Many studies reported that obesity rate in the Western countries is higher in schizophrenia patients than in general population. In this study, we surveyed nationwide Body Mass Index (BMI) status of hospitalized Japanese schizophrenia patients. Methods: Subjects included 15,171 patients (7,897 men and 7,274 women) hospitalized for schizophrenia, who were sampled from all 47 administrative divisions in Japan. The BMI data of these patients were compared to those of the general population in the 2009 National Health and Nutrition Survey conducted by the Japanese Ministry of Health. Results: The median BMI value in the patients was 21.6 kg/m2 (first quartile, 19.1; third quartile, 24.5). The percentages of BMI in obese, normal-weight, and underweight patients were 21.6%, 58.2%, and 20.2%, respectively. In the Japanese male patients, frequency of obesity was lower, and underweight was higher than those in the general population. In female patients, frequency of both obesity and underweight were higher than those in the general population. Conclusions: Our results provided evidence that underweight as well as obesity is a characteristic in Japanese schizophrenia inpatients. © 2012, Baywood Publishing Co., Inc.

Tojo H.,Japan Forestry and Forest Products Research Institute | Nakamura S.,Tokiwa University
Ornithological Science | Year: 2014

The Red-billed Leiothrix Leiothrix lutea has been introduced to, and become established in Japan, the Hawaiian Islands and certain areas of Europe. Unlike in its native range, introduced Red-billed Leiothrix populations have not been observed to be hosts of avian brood parasites. We found a parasite egg with three host eggs in a Red-billed Leiothrix nest on 14 July 2010 on Mt Tsukuba, central Japan. Despite its marked difference from the host eggs, the parasite egg was accepted and incubated by the l Red-billed Leiothrix parent until the nest was depredated before hatching. The morphology of the parasite egg suggested that it belonged to Oriental Cuckoo Cuculus optatus. © The Ornithological Society of Japan 2014.

PubMed | Tokiwa University, Juntendo University and Kyoto University
Type: Journal Article | Journal: Biochemical and biophysical research communications | Year: 2016

Ethambutol is a common medicine used for the treatment of tuberculosis, which can have serious side effects, such as retinal and liver dysfunction. Although ethambutol has been reported to impair autophagic flux in rat retinal cells, the precise molecular mechanism remains unclear. Using various mammalian cell lines, we showed that ethambutol accumulated in autophagosomes and vacuolated lysosomes, with marked Zn(2+) accumulation. The enlarged lysosomes were neutralized and were infiltrated with Zn(2+) accumulations in the lysosomes, with simultaneous loss of acidification. These results suggest that EB neutralizes lysosomes leading to insufficient autophagy, implying that some of the adverse effects associated with EB in various organs may be of this mechanism.

Popovski V.,University of Tokyo | Mundy K.G.,Tokiwa University
Sustainability Science | Year: 2012

This article introduces the concept of "climate-change victims" and classifies categories of threats and groups of people who would be vulnerable to and victimized by human-induced climate change. (The full, correct wording is "human-induced climate-change victims", but we will use just "climate-change victims" in the rest of the article.) It offers a definition with three levels of climate-change victimization and differentiates "climate-change victims" from "natural-disasters victims" and from "climate-change migrants". The article sets an agenda for a new type of victimhood and could lead to further research on possible prevention, accountability measures, environmental tribunals, and compensation mechanisms to recompense climate-change victims. © 2011 Integrated Research System for Sustainability Science, United Nations University, and Springer.

Nakahara F.,Tokiwa University | Miyazaki N.,University of Tokyo
Journal of Ethology | Year: 2011

Bottlenose dolphins (Tursiops truncatus) produce individually distinctive vocalizations-referred to as "signature whistles"-that are thought to function as an individual and conspecific recognition system for maintenance of consistent contact between individuals. Observations and playback experiments were conducted at aquariums to study these whistle-vocal exchanges in bottlenose dolphins. Temporal patterns of vocalization were examined by analyzing the intercall intervals between two consecutive whistles. When a second individual produced a call that was different from the first individual's vocalization, most of these calls were shorter than 1 s. However, when two consecutive calls were produced by the same individual, the second call rarely occurred within 1 s of the first. These results suggest that a second whistle may be produced by a different caller in response to the first whistle; however, in the case of an absence of a response, the first caller is likely to give further whistles. The results of this acoustic analysis show that the dolphins used in this study mostly used signature whistles during the recorded vocal exchanges. © 2011 Japan Ethological Society and Springer.

Moriyama T.,Tokiwa University | Kazama L.,Tokiwa University | Obata S.,Tokiwa University | Nakamura T.,Tokiwa University
Revista Mexicana de Analisis de la Conducta | Year: 2015

Resurgence of newborns’ operant responses that have been reinforced by phylogenetically important events has not yet been investigated. The present study investigated whether, in newly hatched chicks, resurgence of key-peck operant responses previously reinforced by delivery of either an imprinted stimulus or food as a reinforcer would recur under extinction. The possibility of intrusion into the resurgence of behavior related to the imprinted stimulus and food as phylogenetically important events was also explored. Ten chicks that were imprinted to a moving stimulus were divided into two groups, using either an imprinted stimulus or food as a reinforcer, respectively. First, their pecking a red key was shaped and maintained under a variable-interval schedule (Phase 1). After pecking rates stabilized, pecking a second, blue, key was reinforced using the same reinforcer as in Phase 1, while pecking the red key was extinguished (Phase 2). After the rates of pecking the red key were extinguished, pecking of either key was extinguished (Phase 3). Resurgence was measured as the number of pecks on the red key in the initial session of Phase 3. Most chicks in both groups showed resurgence of pecking the red key during the final extinction phase. However, the magnitude of resurgence was much stronger in the food group than the imprintedstimulus group, and resurgence in both groups occurred at a relatively early stage of extinction. Furthermore, while resurgence of responses reinforced by the imprinted stimulus was accompanied by responses related to the imprinted stimulus, resurgence of responses reinforced by food was accompanied by those related to food. These results were discussed in terms of potential biological and behavioral constraints on resurgence, response chains, and related recurrence procedures. © 2015, Sociedad Mexicana de Analisis de la Conducta. All rights reserved.

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