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Thermoregulation is impaired in individuals with a spinal cord lesion (SCI), affecting sweat capacity, heat loss, and core temperature. This can be particularly problematic for athletes with SCI who exercise in hot and humid conditions, like those during the Tokyo 2020 Paralympic Games. Heat acclimation can support optimal preparation for exercise in such challenging environments, but evidence is limited in endurance athletes with SCI. We evaluated whether seven consecutive days of exercise in the heat would result in heat acclimation. Five elite para-cycling athletes with SCI participated (two females, three males, median (Q1-Q3) 35 (31–51) years, four with paraplegia and one with tetraplegia). All tests and training sessions were performed in a heat chamber (30°C and 75% relative humidity). A time-to-exhaustion test was performed on day 1 (pretest) and day 7 (posttest). On days 2–6, athletes trained daily for one hour at 50–60% of individual peak power (PPeak). Comparing pretest and posttest, all athletes increased their body mass loss (p=0.04), sweat rate (p=0.04), and time to exhaustion (p=0.04). Effects varied between athletes for core temperature and heart rate. All athletes appeared to benefit from our heat acclimation protocol, helping to optimize their preparation for the Tokyo 2020 Paralympic Games. [ABSTRACT FROM AUTHOR]

Low-temperature adaptation in rice is mediated by the ability of a genotype to tolerate chilling temperatures. A genetic locus on chromosome 11 was analysed for chilling tolerance at the plumule stage in rice. The tolerant allele of A58, a japonica landrace in Japan, was inherited as a recessive gene (ctp-1 A58), whereas the susceptible alleles from wild rice (Ctp-1 W107) and modern variety (Ctp-1 HY) were the dominant genes. Another recessive tolerant allele (ctp-1 Silewah) was found in a tropical japonica variety (Silewah). Fine-mapping revealed that a candidate gene for the ctp-1 locus encoded a protein similar to the nucleotide-binding domain and leucine-rich repeat (NLR) protein, in which frameshift mutation by a 73 bp-deletion might confer chilling tolerance in ctp-1 A58. Analysis of near-isogenic lines demonstrated that ctp-1 A58 imparted tolerance effects only at severe chilling temperatures of 0.5 °C and 2 °C, both at plumule and seedling stages. Chilling acclimation treatments at a wide range of temperatures (8 °C–16 °C) for 72 h concealed the susceptible phenotype of Ctp-1 W107 and Ctp-1 HY. Furthermore, short-term acclimation treatment of 12 h at 8 °C was enough to be fully acclimated. These results suggest that the NLR gene induces a susceptible response upon exposure to severe chilling stress, however, another interacting gene(s) for acclimation response could suppress the maladaptive phenotype caused by the Ctp-1 allele. This study provides new insights for the adaptation and breeding of rice in a low-temperature environment. [ABSTRACT FROM AUTHOR]

To prepare and manage urban greenspace for a hotter future, we must select trees that can tolerate or acclimate to high temperatures. Here, we compared tolerance and acclimation to high temperatures among nine urban tree species in Japan. Saplings were exposed to heat from different times (early and mid-summer) during the growing season in a greenhouse. With the exception of Ginko, heating in early summer did not affect whole-tree health, suggesting that most urban tree species may be able to acclimate to higher temperatures during the early growing season. However, continued exposure to higher temperatures, as well as heating from mid-summer, had negative effects on tree health, leading to wilting/browning, especially for evergreen broadleaved species whose leaves mature slowly. Cornus florida, Styrax japonicus and Morella rubra were the most vulnerable to heating, such that all heated saplings had died by the end of summer. At the leaf level, leaf maturation of the deciduous species and Morella was negatively affected by heating, whereas that of Eurya emarginata and Euonymus japonicas were not affected. These two species also showed heat tolerance, having a higher T50 (temperature where leaf quantum yield declined to 50% of maximum value due to heat stress) compared to other species, as well as heat acclimation, where T50 was higher for the heated saplings compared to the control. Our results indicate that, while some species that cannot recover from heat damage in early summer could die, others can acclimate to sustained high temperatures, as well as to late summer heat. As heatwaves are expected to become more frequent and severe due to global warming, tree species need to be screened individually to assess their ability to tolerate or acclimate to high temperature. [ABSTRACT FROM AUTHOR]

• The establishment of micropropagation protocol for Cameron Highlands White Strawberry. • High multiplication rate in full-strength MS medium + 8 µM TDZ. • No damage to the cellular arrangement was observed on the treated in vitro plants in any of the light treatments using scanning electron microscopy (SEM). • Maximum acclimatization efficiency in hydroponic solution (100% survival rate). White strawberry is botanically a member of the Fragaria genus, which is a part of the Rosaceae family, which is primarily found in Japan, where it is a well-known premium fruit. Experiments were conducted to develop a micropropagation method for Cameron Highlands white strawberries (Fragaria x Ananassa). Freshly extracted achenes were surface sterilised with 30 and 40% Clorox®. Achenes germination was studied in vitro under various light spectra [cool white LED (17.0 μ mol/s), red LED (29.30 μ mol/s), blue LED (15.70 μ mol/s), red + blue LEDs (44.80 μ mol/s)] to study how light and different LED spectra affected shoot, root, and leaf growths of seedlings in the culture. Because both treatments have a 0% contamination rate and the same germination rate which is 78.77%, the 30% Clorox® treatment was chosen as the best surface sterilisation protocol for white strawberry achene germination. Scanning electron microscopy (SEM) studies of seedlings germinated under various light treatments demonstrated that no damage to the cellular arrangement was observed in any of the light treatments. However, the stomata of seedlings treated with blue LED were found to be damaged and exhibit uneven structures. Shoot multiplication in the culture was determined by testing various concentrations of 6- benzylaminopurine (BAP) and thidiazuron (TDZ) using shoot tips (0.5 to 0.8 cm) from the 5-leaf stage of the in vitro plants. The highest mean number (6.50 ± 1.05) of shoots differentiated on MS medium with 8 µM TDZ. The regenerated plantlets were rooted on MS medium with indole-3-butyric acid (IBA) and 1-Naphthaleneacetic acid (NAA) at 0 (control), 1, 2, 3, and 5 µM. Rooting (50%) was the highest success with 1 µM IBA. All the rooted plantlets were successfully acclimatized using hydroponics and field transfer. [ABSTRACT FROM AUTHOR]

Recent climate change has resulted in warmer temperatures. Warmer temperatures from autumn to spring has negatively affected dormancy progression, cold (de)acclimation, and cold tolerance in various temperate fruit trees. In Japan, a physiological disorder known as flowering disorder, which is an erratic flowering and bud break disorder, has recently emerged as a serious problem in the production of the pome fruit tree, Japanese (Asian) pear (Pyrus pyrifolia Nakai). Due to global warming, the annual temperature in Japan has risen markedly since the 1990s. Surveys of flowering disorder in field-grown and greenhouse-grown Japanese pear trees over several years have indicated that flowering disorder occurs in warmer years and cultivation conditions, and the risk of flowering disorder occurrence is higher at lower latitudes than at higher latitudes. Susceptibility to flowering disorder is linked to changes in the transcript levels of putative dormancy/flowering regulators such as DORMANCY-ASSOCIATED MADS-box (DAM) and FLOWERING LOCUS T (FT). On the basis of published studies, we conclude that autumn–winter warm temperatures cause flowering disorder through affecting cold acclimation, dormancy progression, and floral bud maturation. Additionally, warm conditions also decrease carbohydrate accumulation in shoots, leading to reduced tree vigor. We propose that all these physiological and metabolic changes due to the lack of chilling during the dormancy phase interact to cause flowering disorder in the spring. We also propose that the process of chilling exposure rather than the total amount of chilling may be important for the precise control of dormancy progression and robust blooming, which in turn suggests the necessity of re-evaluation of the characteristics of cultivar-dependent chilling requirement trait. A full understanding of the molecular and metabolic regulatory mechanisms of both dormancy completion (floral bud maturation) and dormancy break (release from the repression of bud break) will help to clarify the physiological basis of dormancy-related physiological disorder and also provide useful strategies to mitigate or overcome it under global warming. [ABSTRACT FROM AUTHOR]

The brackish water bivalve Corbicula japonica, a target species for seedling release in Japan, inhabits environments subject to drastic salinity changes. The burrowing behavior of C. japonica in sand decreases predation. To improve their survival after release, the effect of salinity change on the burrowing behavior of adult C. japonica was observed in tank experiments. We found that salinity changes had a significantly negative effect on burrowing behavior, while acclimatization to constant salinity had a positive effect. No burrowing behavior was observed even after 24 h when the salinity change was large (range: ±25), whereas individuals burrowed within 0.56 h when the salinity did not change (range: 0). We estimated that, when there was no acclimatization period to a constant salinity, the range of salinity change for which burrowing was common was −4.7 to +9.9. We conclude that acclimatization to the salinity of the release site effectively promotes quick burrowing and, consequently, the survival of C. japonica after release. Alternatively, the production areas should have the same salinity environment as the release site. [ABSTRACT FROM AUTHOR]

Plants can acclimate their photosynthesis to growth temperature, but the contribution of local adaptation to intraspecific variation in thermal acclimation of photosynthesis is not fully understood. Here, we experimentally investigated the photosynthetic thermal acclimation in Fagus crenata Blume seedlings from two populations growing at different elevations and temperature regimes (low- and high-elevation sites) in northern Japan. We acclimated seedlings for 14 to 23 days at daytime temperatures of either 22 °C (control) or 27 °C (warm treatment) and obtained photosynthetic temperature-response curves in the range of 19 to 32 °C. The optimum temperature of photosynthesis (Topt) was ~0.6 °C higher in seedlings acclimated at 27 °C than in those acclimated at 22 °C, and it was significantly lower in seedlings with higher stomatal sensitivity to leaf-to-air vapor pressure deficit than in those with lower sensitivity. The effects of warm treatment, population and treatment-population interaction on Topt were not significant in the two-way analysis of variance, but the effect of treatment became significant when stomatal sensitivity to leaf-to-air vapor pressure deficit was included as a covariate in the model. Structural equation modeling indicated that seedlings with lower root biomass had lower Topt because of the high stomatal sensitivity to leaf-to-air vapor pressure deficit. Structural equation modelling also indicated that the way of shifting the Topt differed between the two populations: seedlings from a high-elevation site depended on decreasing photosynthetic rates at low temperatures for the increase in Topt but seedlings from a low-elevation site did not. We suggest that the difference in thermal acclimation of photosynthesis between the two populations may reflect adaptation to different climate regimes and that belowground traits should be considered when investigating thermal acclimation capacity, especially in seedlings., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Transgenerational responses of susceptible calcifying organisms to progressive ocean acidification are an important issue in reducing uncertainty of future predictions. In this study, a two-generation rearing experiment was conducted using mature Mesocentrotus nudus, a major edible sea urchin that occurs along the coasts of northern Japan. Morphological observations and comprehensive gene expression analysis (RNA-seq) of resulting larvae were performed to examine transgenerational acclimation to acidified seawater. Two generations of rearing experiments showed that larvae derived from parents acclimated to acidified seawater tended to have higher survival and show less reduction in body size when exposed to acidified seawater of the same pH, suggesting that a positive carry-over effect occurred. RNA-seq analysis showed that gene expression patterns of larvae originated from both acclimated and non-acclimated parents to acidified seawater tended to be different than control condition, and the gene expression pattern of larvae originated from acclimated parents was substantially different than that of larvae of non-acclimated and control parents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hypoxia-tolerant bivalve populations could be a key component of ecosystem function because of their predominance in hypoxic environments. In this study, we conducted field surveys at two sites to elucidate the biological traits of the hypoxia-tolerant bivalve Veremolpa micra. We detected new settlements at both sites during summer. More highly reduced conditions in the surface sediment were recorded at Site-A than at Site-B in August 2013. Following this hypoxic event, shell growth of V. micra at Site-A decelerated, whereas that at Site-B increased. The population density after recovery from the hypoxic event decreased more at Site-B than at Site-A. Body size exhibited very little growth at both sites during the fall and winter, but there was rapid growth during the subsequent spring and summer, with sexual maturity being reached in early summer. Our findings demonstrated that the growth rates and survival patterns of the hypoxia-tolerant bivalve populations differed between sites with different degrees of sediment reduction. To understand the biological traits of hypoxia-tolerant bivalve species, it is necessary to consider and evaluate spatial differences in hypoxic stress at the local site level. [ABSTRACT FROM AUTHOR]

Global climate change increases uncertainty in sustained functioning of forest ecosystems. Forest canopies are a key link between terrestrial ecosystems, the atmosphere, and climate. Here, we introduce research presented at the 66th meeting of the Ecological Society of Japan in the symposium "Structure and function of forest canopies under climate change." Old‐growth forest carbon stores are the largest and may be the most vulnerable to climate change as the balance between sequestration and emission could easily be tipped. Detailed structural analysis of individual large, old trees shows they are allocating wood to the trunk and crown in patterns that cannot be deduced from ground, thus can be used to more accurately quantify total forest carbon and sequestration. Slowly migrating species sensitive to novel climatic conditions will have to acclimate at the individual level. Accounting for physiological responses of trees to climate change will improve predictions of future species distributions and subsequent functioning of forest ecosystems. Field experiments manipulating temperature and precipitation show how trees compensate physiologically to mitigate for higher temperatures and drought. However, it is difficult to measure acclimation responses over long timeframes. Intraindividual trait variation is proposed as an indicator of acclimation potential of trees to future conditions and suggests that acclimation potential may vary among regional populations within a species. Integrating whole‐tree structural data with physiological data offers a promising avenue for understanding how trees will respond to climatic shifts. [ABSTRACT FROM AUTHOR]

Ornithomimosauria consists of the ostrich-mimic dinosaurs, most of which showing cursorial adaptations, that often exhibit features indicative of herbivory. Recent discoveries have greatly improved our knowledge of their evolutionary history, including the divergence into Ornithomimidae and Deinocheiridae in the Early Cretaceous, but the early part of their history remains obscured because their fossil remains are scarce in the Aptian-Albian sediments. In recent years, many isolated ornithomimosaur remains have been recovered from the Aptian Kitadani Formation of Fukui, central Japan. These remains represent multiple individuals that share some morphological features common to them but unknown in other ornithomimosaurs, suggesting a monospecific accumulation of a new taxon. As a result of the description and phylogenetic analysis, the Kitadani ornithomimosaur is recovered as a new genus and species Tyrannomimus fukuiensis, the earliest definitive deinocheirid that complements our knowledge to understand the early evolutionary history of Ornithomimosauria. Due to its osteological similarity to Tyrannomimus, a taxon previously considered an early tyrannosauroid based on fragmentary specimens, namely Aviatyrannis jurassica, may represent the earliest ornithomimosaur from the Upper Jurassic of Europe, significantly expanding the temporal and biogeographic range of Ornithomimosauria. This finding fills a 20-million-year ghost lineage of Ornithomimosauria implied by the presence of the oldest fossil record of Maniraptora from the Middle Jurassic and is consistent with the hypothesis that their biogeographic range was widespread before the Pangaean breakup in the Kimmeridgian., (© 2023. Springer Nature Limited.)

• Japanese cedar canopy CO 2 and H 2 O fluxes were modeled using leaf physiology data. • Model analysis using leaf physiology data explained the leaf physiology seasonality. • Cold acclimation during the winter substantially influenced flux modeling. • Lower photosynthetic ability during winter is required to maintain the ecosystem. Recently, requests for forest management to conserve water resources and sequester carbon have increased in Japan, where approximately 27% and 12% of the total land area are covered by forest plantations and Japanese cedar (Cryptomeria japonica D. Don). To formulate better forest management practices that maximize forest functions by maintaining water and carbon cycles, an understanding of how leaf-level ecophysiological traits influence canopy-level CO 2 and H 2 O exchanges in Japanese cedar plantations is required. In this study, observations of eddy covariance flux and leaf ecophysiology in a Japanese cedar plantation in southern Japan indicate that significantly greater productivity and seasonal variations tend to occur in canopy CO 2 and H 2 O fluxes, with seasonal patterns of photosynthetic traits (maximum carboxylation rate normalized at 25 °C, V cmax,25) and leaf area index (LAI). We also examined how biotic (e.g., V cmax,25 and LAI) and abiotic (e.g., meteorological variables) factors govern canopy fluxes using a multi-layer soil–vegetation–atmosphere transfer (SVAT) model. The model validation suggests that seasonal variations in V cmax,25 and LAI must be included to reproduce the fluxes observed in the plantation. Quantitative experiments using the validated SVAT model indicate that considering cold acclimation during the winter improved the reproducibility of the model with regard to the measured fluxes, constant high intra-annual LAI had the least impact on forest productivity, and a consistently high V cmax,25 value increased forest productivity but considerably decreased the nitrogen use efficiency and required a larger nitrogen supply from the ecosystem during the winter. These findings highlight the necessity of decreasing photosynthetic ability during the winter, which safeguards the ecosystem's nitrogen resources to sustain the productivity of the Japanese cedar plantation throughout the year. [Display omitted] [ABSTRACT FROM AUTHOR]

Climate extremes are expected to become more frequent and intense under future warming. In a globalized economy, outages of productive capital and infrastructure have the potential to spread around the world. In order to address those repercussions in the framework of a risk analysis or a resilience strategy, a disaster's indirect consequences on the economic supply network need to be understood. We developed a numerical model to simulate these indirect effects along global supply chains for time scales of days to months. This article is the first in a series of four, which describes the damage-propagation model. In this first paper, we describe the pure damage propagation within the network and focus on the fundamental propagation of supply failure between production sites including their input and output storages and transport-related time delay. Idealized examples are presented to illustrate the dynamic damage propagation. Further articles will extend the dynamics to include demand changes due to the perturbation in the supply, the possibility to extend production to compensate for production failure, price responses and adaptive changes in the economic supply network. The underlying global supply network is based on data from multi-regional input-output tables. Transportation times are derived from geographic distances. In the initial model version presented here, indirect production losses are caused by cascading effects. They are propagated within the network without significant reduction in loss (damage conservation). They can thus be observed within the different storages or they 'leak out' of the system through reduced consumption of the final consumer. As an example, we investigate the cascading behavior of losses for the machinery sector in Japan. [ABSTRACT FROM AUTHOR]

The article examines the interaction between mtDNA haplogroup and seasonal variation that contributes to cold adaptation. It states that the study involved Japanese students that were placed in an environment where the ambient temperature dropped from 27 °Celsius to 10 °Celsius in 30 minutes. It also mentions that the group differences in cold adaptability observed in summer may reduce in winter by seasonal cold acclimatization due to supplementation.

Abstract: The purpose of this study was to examine the deacclimatization of the cutaneous thermal sensations of tropical indigenes residing in temperate climates. Tropical indigenes (n=13) who were born and raised in tropics but had resided in Japan for 5–61 months participated in this study, along with temperate indigenes (n=11). Their cutaneous thermal thresholds for warm, cool, hot, and cold sensations were measured in 12 body regions using a thermal stimulator controlled by a Peltier element and a push button switch. Subjects pressed the button-switch as soon as they perceived a feeling of being ‘slightly warm’, ‘slightly cool’, ‘hot’, or ‘cold’ from a neutral thermal state. Our results showed that: (1) among the tropical indigenes, no significant relationship was found between the duration of their stay in Japan and their cutaneous thermal thresholds; (2) the tropical indigenes were, on average, 3.3, 3.5, 4.2, and 7.3°C less sensitive to warm, hot, cool, and cold sensations, respectively, than the temperate indigenes (P<0.05); and (3) the inter-threshold sensory zones between cutaneous warmth and coolness, and hot and cold sensations were wider among the tropical indigenes than among the temperate indigenes. It was concluded that the nature of the heat acclimatization of the cutaneous thermal thresholds for the tropical indigenes was retained despite their residence in a temperate climate for up to 61 months, indicating that they had more blunted perceptions of both warming and cooling than the temperate indigenes. [Copyright &y& Elsevier]

To clarify the effects of altitude acclimatization on postural instability at altitudes, six female climbers stood with their eyes open or closed on a force-measuring platform under normoxia (NC) and hypobaric hypoxia, equivalent to a 5,000 m altitude (HC), before and after an expedition to Mt. Cho-Oyu (8,201 m). The expedition extended over 84 days. We recorded sways in the center of foot pressure, electromyograms (EMGs) of lower-leg muscles, blood components and arterial oxygen saturation (SpO(2)). Before the expedition, the maximum amplitude of sway with the eyes open and integrated EMG from the medial gastrocnemius increased for HC. After the expedition, red blood cell (from 423.4 ± 15.4 to 498.0 ± 24.5 × 10(4) μl(-1)), hemoglobin content (from 12.6 ± 0.32 to 14.5 ± 1.00 g/dl) and 2,3-diphosphoglycerate (from 1.93 ± 0.21 to 2.24 ± 0.34 μmol/ml) increased. The SpO(2) under HC increased from 69.2 ± 9.6 to 77.2 ± 10.0%. The maximum amplitude of sway with the eyes open decreased for HC. No difference in the sway path length and integrated EMGs was observed between NC and HC. These results suggest that acclimatization can improve the impaired postural stability on initial arrival at altitudes. However, it is still unclear how long acclimatization period is needed. Further studies are needed to reveal this point. [ABSTRACT FROM AUTHOR]

Photosynthetic activities of seedlings of Zostera marina were successively measured using a gas volumeter for 6 days at seven light (0–400 μmol photons/m2 per s) and 11 water temperature conditions (5–35°C). The seedlings were collected from mature plants (Ise Bay, central Japan), and stored and cultured in incubators accurately controlled at each test temperature. The maximum gross photosynthesis ( Pmaxg) was recorded at an optimal water temperature of 29°C after 0 days. After 6 days, Pmaxg appeared at 25°C and most plants cultured at 29–30°C bleached and withered after the drastic increase of light compensation point ( Ic). On the contrary, at 5–28°C, the photosynthetic activities either changed little (5–25°C) or recovered after a temporal reduction (26–28°C); seedlings survived and looked healthy after being cultured for 6 days. The recovery was thought to be an acclimation to tolerate higher water temperature. As a result, the critical upper water temperature for Z. marina seedlings was proposed as 28°C. The temperature was consistent with the previously reported maximum water temperature in habitats around the southern boundary of Z. marina in the northern hemisphere. [ABSTRACT FROM AUTHOR]

Aim To estimate the potential effect of global climate change on the phenological responses of plants it is necessary to estimate spatial variations at larger scales. However, previous studies have not estimated latitudinal patterns in the phenological response directly. We hypothesized that the phenological response of plants varies with latitude, and estimated the phenological response to long-term climate change using autumn phenological events that have been delayed by recent climate change. Location Japan. Methods We used a 53-year data set to document the latitudinal patterns in the climate responses of the timing of autumn leaf colouring and fall for two tree species over a wide range of latitudes in Japan (31 to 44° N). We calculated single regression slopes for leaf phenological timing and air temperature across Japan and tested their latitudinal patterns using regression models. The effects of latitude, time and their interaction on the responses of the phenological timings were also estimated using generalized linear mixed models. Results Our results showed that single regression slopes of leaf phenological timing and air temperature in autumn were positive at most stations. Higher temperatures can delay the timing of leaf phenology. Negative relationships were found between the phenological response of leaves to temperature and latitude. Single regression slopes of the phenological responses at lower latitudes were larger than those at higher latitudes. Main conclusions We found negative relationships between leaf phenological responsiveness and latitude. These findings will be important for predicting phenological timing with global climate change. [ABSTRACT FROM AUTHOR]

We studied the behavioral thermoregulation of Japanese macaques in two troops that live in the coniferous (1,000–1,200 m in elevation) and coastal forests (0–200 m in elevation) of Yakushima. Frequency of sunbathing, huddling, and microhabitat selection during inactivity was compared. The difference in mean annual air temperature between the forests was more than 7°C. In both forests, when the weather was clear, macaques spent more time being inactive in the sunshine in winter than in autumn. In winter, they huddled more often when it was clear than when cloudy. Microhabitat selection to stay in the sunshine during winter differed between the two forests. In winter, macaques spent more time inactive in open habitats in the coniferous forest and in the trees in the coastal forest than in autumn, respectively. This difference is related to the lower crown height in the coastal forest and the large open habitats (logged area) available only in the coniferous forest. In winter, skin temperature measured by temperature-sensitive transmitters was 1.32–1.71°C higher when sunbathing, and 0.83–4.75°C higher when huddling than staying in the shade without huddling. In winter, the proportion with which they stayed in the sunshine or huddled in winter did not differ between the two forests, in spite of the difference in air temperature. This suggests that Japanese macaques respond to seasonal changes in air temperature, not the absolute temperature, and that they acclimatize themselves to thermal conditions that require behavioral thermoregulation only during the season when thermoregulation is most costly. Am. J. Primatol. 69:802–815, 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

To elucidate the effects of seasonal temperature acclimatization on thermal gelation of grass carp myosin, myosins from fish in different seasons were prepared and investigated for the changes in dynamic viscoelastic parameters including storage modulus (G′), loss modulus (G′′) and damping factor (tan δ) upon heating. Myosins from fish in spring and summer had a temperature region of 38–44°C for the first marked increase of G′ higher than that of myosins from fish in autumn and winter (28–33°C). The measurement temperature-dependent changes in dynamic viscoelastic parameters such as G′′ and tan δ were also different among the four myosins. While gel formation was observed with the spring and summer myosins, apparently in two steps, three steps were found in the autumn myosin. Furthermore, the winter myosin exhibited more than three steps for gel formation. These differences in rheological properties among the four myosins were considered to be attributed to the differences in thermodynamic and structural properties of these myosins previously reported. [ABSTRACT FROM AUTHOR]

Tropical natives possess heat tolerance due to the ability to off-load endogenous and exogenous heat efficiently using a minimum amount of sweat. On the other hand, exposure of temperate natives to heat results in exaggerated production of sweat, of which part is lost by dripping and, thus, not available for evaporation. How sweating is modified in natives of temperate climate zones by prolonged residence in the tropics is not well-understood. The aim of this study was to investigate possible changes in the peripheral sweating mechanisms. Sweating responses to iontophoretically applied acetylcholine (ACh) were compared between Japanese subjects having either permanently resided in Japan (Japan resident Japanese, JRJ) or having stayed in the tropics for 2 years or longer (Tropics resident Japanese, TRJ). Quantitative sudomotor axon reflex tests by iontophoresis of ACh (10%, 2 mA for 5 min) were applied to determine directly activated (DIR) and axon reflex-mediated sweating during [AXR(1)] and after [AXR(2)] ACh iontophoresis. The sweat onset time of AXR(1) was 0.6 min shorter in JRJ than in TRJ (P<0.0001), and AXR(1) (P<0.0004), AXR(2) (P<0.0001), and DIR (P<0.0001) sweating responses were larger in JRJ than in TRJ. AXR and DIR sweating volumes (P<0.0001) were negatively correlated, and sweat onset times (P<0.0001) were positively correlated with the duration of residence in the tropics (2 to 13 years). The observed attenuation of sweating in TRJ suggests that temperate natives may acquire heat tolerance with improved sweating economy similar to tropical natives after prolonged residence in the tropics. [ABSTRACT FROM AUTHOR]

Abstract Long-term changes in the demersal assemblage, including both fishes and invertebrates, in Tokyo Bay, Japan, were examined between 1977 and 1995. A total of 255 species were collected, of which 113 were regarded as representative in terms of occurrence. Multivariate analyses of the representative species showed that fluctuations in the catch were related to three periods that reflected changes in relative abundance and species composition. In particular, mantis shrimp, Oratosquilla oratoria (de Haan), whipfin dragonet, Repomucenus valenciennei (Temminck & Schlegel), and marbled sole, Pleuronectes yokohamae Günther, showed high dominance in the mid-1980s. Discriminant analysis suggested that the demersal assemblage changed synchronously with environmental conditions. Causes of the temporal changes in the demersal assemblage in relation to variations in environmental factors are discussed. [ABSTRACT FROM AUTHOR]

Lethal limits of high temperature were studied to clarify the effects on the survival of the endangered Japanese crayfish species Cambaroides japonicus and the alien species Pacifastacus leniusculus . After the acclimation period for 2 weeks at 16°C, the temperature was raised at a rate of 1°C per week. As a result, the ultimate upper lethal temperatures of C. japonicus and P. leniusculus were 27.0 and 31.1°C, respectively, and the lethal temperature for P. leniusculus was significantly higher than for C. japonicus . The natural distributions of these two species are discussed in terms of the temperature tolerance. [ABSTRACT FROM AUTHOR]

Although many investigations have been conducted to determine the effects of exercise and/or diet prescription, seasonal variations in weight loss have not been thoroughly investigated in Japan. The present investigation was undertaken to determine seasonal variations in body composition and anthropometric characteristics during a weight-loss program. One hundred and twenty-seven women [mean (SD) age 44.3 (11.7) years] participated in this study. The subjects were categorized into four groups based on the season in which the weight-loss program was begun: subjects who joined our exercise program in winter (group WE), subjects who joined in summer (group SE), and two control groups, one for winter and one for summer (group WC and group SC, respectively). The subjects of groups WE and SE completed a 3-month exercise and food-restriction program. Analyses of covariance revealed that the subjects of group WE seemed to have attained more desirable changes. This group showed a decrease in body mass (–1.9 (1.5) kg) and percent body fat (–4.6 (4.8)%), while an increase in fat-free mass (1.6 (3.2) kg) during the experimental period. Our data suggest that the better season for desirable weight loss in Japan is winter, compared to summer. These alterations may be attributable, at least in part, to the fact that Japanese people are generally acclimatized to a cold climate in this season. The mechanisms involved in our speculation have not been well validated, but it seems clear that a significant difference in dietary intake might have affected the results of this study. [ABSTRACT FROM AUTHOR]

Ocean warming has facilitated the range expansion of commercially important sea urchin species to higher latitudes. Heliocidaris crassispina was recorded to extend northward to Toga Bay along the Oga Peninsula, Japan following an increase in seawater temperatures, and replacement of local sea urchin species Mesocentrotus nudus. In order to identify evidence of adaptation occurring in response to a range extension of H. crassispina to the newly extended environments, we randomly collected 106 H. crassispina in August 2014 in Toga Bay, determined the growth and age composition and examined gonad traits (size, color and development). To confirm the gonad development, 30 H. crassispina with > 30 mm diameter were collected in July, August and September 2017. We found slower growth in the extended range than the central range. More delayed gonad development of males than those of females and a large variety of developmental stages in the acini of testis indicated that the spawning of both sexes of the sea urchins were asynchronous. In terms of gonad color, L* (lightness) values increased with increasing GI, while b* (yellowness) values decreased with increasing age. The population consisted of seven year-classes from 2006 to 2012, suggesting persistent juvenile recruitment. Long-term water temperature data indicated that the range extension of H. crassispina was due to ocean warming, in particular during the summer spawning season., Competing Interests: The authors have declared that no competing interests exist.

The present study assessed whether non-anadromous masu salmon Oncorhynchus masou in Miyazaki, southern Japan, smoltify, and if so, at what time of the year. Yearling O. masou of Miyazaki and an anadromous population from Hokkaido, northern Japan, were reared in hatcheries in their respective regions and sampled monthly from February to June to examine the spring smoltification period. The Hokkaido population showed a peak of gill Na + -K + -ATPase (NKA) activity in May, which was accompanied with an increase in mRNA levels of the seawater (SW)-type NKA alpha subunit, nkaα1b. Increases in gill NKA activity and nkaa1b levels were not seen in Miyazaki populations. Transferring yearling Miyazaki population to 70% SW (salinity of 23) in mid-April resulted in an increased serum osmolality over 4 days. These results suggest that they do not smoltify in their second spring. Next, profiles of gill NKA activity and its subunit mRNA levels in under-yearling Miyazaki population in the autumn were examined. Two phenotypes differing in body color during this period were categorized as parr and smolt-like fish. Smolt-like fish had higher gill NKA activity than parr in December while there was no significant difference in gill nkaα1b levels. Smolt-like fish acclimated to 70% SW better than parr as judged by lower serum osmolality. However, serum osmolality in smolt-like fish did not return to the basal level 7 days after transfer to 70% SW, suggesting that their hypo-osmoregulatory ability was not fully developed to a level comparable to anadromous populations of this species. The present study suggests that, if O. masou in Miyazaki go though a smoltification process, it occurs in its first autumn instead of the second spring and is less pronounced compared with anadromous populations., (© 2018 The Fisheries Society of the British Isles.)

Although laboratory observations provide basic knowledge of the development and reproduction of predacious and phytophagous mites, little is known of their behavior under natural conditions. Using a closed system designed to simulate natural climate patterns, we investigated the development and reproduction of the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) and the pest mite Tetranychus urticae Koch (Acari: Tetranychidae) at air temperatures typical of June to October at three latitudes (Aomori, Tottori, and Naha) in Japan. The peaks of development in both species showed similar trends at each location. The shortest developmental times for both species were observed during August in Aomori, from July to September in Tottori and during August and September in Naha. Development of T. urticae was not completed during October in Aomori due to the decreased air temperature. High reproduction (number of eggs produced during 5 d from the first oviposition) of N. californicus was attained at the conditions that shortened the developmental times (i.e., high-temperature months). T. urticae showed a reproduction trend similar to that of N. californicus except for the low number of eggs produced during August in Naha due to the high mortality of adult females and during October in Tottori due to diapause incidence. This information is in agreement with field observations and together might be useful for planning biological control programs for phytophagous mites and for successful establishment of predacious mites in new habitats.

The author discusses the Kyoto Protocol, which stays a significant emblem of multilateralism and in assuring the long-term survival of Kyoto, Japan, will expire in 2012. The author is critical on the 1992 United Nations (UN) Framework Convention on Climate Change. Also investigated is the Kyoto experiment's key premise, wherein binding international commitments would drive the national efforts and the development in climate-change negotiations.

Representatives from 47 nations have endorsed a 10-year plan to share Earth-observation data, identify gaps in observational efforts, and come up with ways to fill them. The agreement, reached at the second Earth Observation Summit in Tokyo, Japan, on April 25, could help improve forecasting of abnormal weather, understanding of climate change, and management of natural resources. The idea behind the effort, called the Global Earth Observation System of Systems, is straightforward: Dozens of observational systems are now generating reams of data that could be far more powerful if they were combined and widely disseminated.

Cicadulina bipunctata was originally distributed in tropical and subtropical regions of the Old World. This leafhopper recently expanded its distribution area to southern parts of temperate Japan. In this study, factors affecting the overwintering ability of C. bipunctata were examined. A series of laboratory experiments revealed that cold acclimation at 15°C for 7days enhanced the cold tolerance of C. bipunctata to the same level as an overwintering population, adult females were more tolerant of cold temperature than adult males, and survival of acclimated adult females was highly dependent on temperature from -5 to 5°C and exposure duration to the temperature. The temperature of crystallization of adult females was approximately -19°C but temperatures in southern temperate Japan rarely dropped below -10°C in the winter, indicating that overwintering C. bipunctata adults in temperate Japan are not killed by freezing injury but by indirect chilling injury caused by long-term exposure to moderately low temperatures. An overwintering generation of C. bipunctata had extremely low overwinter survival (<1%) in temperate Japan; however, based on winter temperature ranges, there are additional areas amenable to expansion of C. bipunctata in temperate Japan., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Obese subjects may be more vulnerable to injury from heat stress, and appear to be less efficient at thermoregulation. Sweat rate, tympanic temperature and osmolality in obese subjects were investigated in Japan during two seasons. The purpose of this study was to examine the relationship between obesity, thermoregulatory response and season. Five obese (BMI, 32.0 ± 4.9 kg/m²) and five non-obese (BMI, 23.2 ± 2.9 kg/m²) men participated in this experiment at latitude 35°10' N and longitude 136°57.9'E. The average atmospheric temperature was 29.1 ± 1.0 °C in summer and 3.3 ± 1.4 °C in winter. Tympanic temperature and sweat rate were measured during leg water immersion at 42 °C for 30 min. Blood samples were analyzed for plasma osmolality. The relationship between tympanic temperature and sweat rate decreased significantly in obese compared to in non-obese subjects in both seasons, there being a lowered sweat rate for any core temperature in obese subjects. Plasma osmolality was significantly higher in obese than in non-obese subjects in both seasons. Thermal sensation increased significantly in non-obese than in obese in winter but not in summer. Our data show that thermoregulatory responses are attenuated in obese subjects compared with controls, suggesting that obese people are at increased risk of heat-related illnesses.

In order to elucidate which physiological event(s) are involved in the seasonal changes of carbohydrate dynamics during winter, we examined the effects of different low temperatures on the carbohydrate concentrations of Japanese pear (Pyrus pyrifolia (Burm.) Nakai). For four winter seasons, large increases in the sorbitol concentration of shoot xylem sap occurred during mid- to late December, possibly due to the endodormancy completion and low-temperature responses. When trees were kept at 15 °C from 3 November to 3 December in order to postpone the initiation and completion of chilling accumulation that would break endodormancy, sorbitol accumulation in xylem sap was always higher from trees with sufficient chilling accumulation than from trees that received insufficient chilling. However, an additional increase in xylem sap sorbitol occurred around late December in trees regardless of whether their chilling accumulation naturally progressed or was postponed. To examine different temperature effects more closely, we compared the carbohydrate concentrations of trees subjected to either 6 or 0 °C treatment. The sorbitol concentration in xylem sap tremendously increased at 0 °C treatment compared with 6 °C treatment. However, an additional increase in xylem sap sorbitol occurred at both the temperatures when sufficient chilling accumulated with a peak coinciding with the peak expression in shoots of the sorbitol transporter gene (PpSOT2). Interestingly, the total carbohydrate concentration of shoots tremendously increased with exposure to 0 °C compared with exposure to 6 °C, but was not affected by the amount of accumulated chilling. Instead, as chilling accumulated the ratio of sorbitol to total soluble sugars in shoots increased. We presumed that carbohydrates in the shoot tissues may be converted to sorbitol and loaded into the xylem sap so that the sorbitol accumulation patterns were synchronized with the progression of dormancy, whereas the total carbohydrate transported into shoots from other storage organs may be related to freezing tolerance acquisition independent of dormancy progression. We thus propose that there are different effects of dormancy progression and low-temperature responses on carbohydrate dynamics in Japanese pear.

This paper examines variables useful in reconstructing oral (caries, antemortem tooth loss, alveolar defects) and physiological (cribra orbitalia, linear enamel hypoplasia) well-being in two bioarchaeological assemblages from Hokkaido, Japan: Okhotsk (n = 37 individuals) and Jomon (n = 60). Findings are compared and contrasted with each other, with published series from Honshu Japan, and samples from climatically near-equivalent Alaska. It was found that more meaningful comparisons of Hokkaido paleohealth could be made with Alaskan material, rather than the more southerly Jomon. Results were ambiguous with respect to physiological well-being. Low levels of LEH in the cold-adapted samples suggest operating in arctic and subarctic environments with marine-based subsistence regimes is not physiologically expensive. However, the relatively high levels of cribra orbitalia in Hokkaido, relative to Alaska, suggest the picture is not straightforward: the reasons for elevated cribra orbitalia in Hokkaido are unclear. The subarctic and arctic samples formed three broadly similar groupings in terms of oral health profiles: (1) Aleuts and Eskimo; (2) Ipiutak and Tigara; (3) Hokkaido Jomon, Okhotsk, and Kodiak Island. Differences between these groupings could be explained with a combination of sample demographics and subsistence orientations. The extremely high frequency of caries in one sample, caribou hunting Ipiutak, may have been influenced by factors such as low levels of dietary magnesium and potentially cariogenic foodstuffs, such as preparations of caribou stomach contents. It was concluded that oral health profiles are potentially sensitive to differences in subsistence strategies among cold-adapted hunter-gatherers, although they lack predictive value., ((c) 2007 Wiley-Liss, Inc.)

Phospholipids of many cold-tolerant organisms have been reported to contain more unsaturated fatty acids than cold-susceptible organisms, a phenomenon known to maintain membrane fluidity at low temperature. However, we have obtained results to the contrary through a comparison of the membrane phospholipids of six temperate and subtropical species belonging to the Drosophila melanogaster species group. With enhancement of cold tolerance, the percentages of monoenoic acids increased but the percentages of dienoic acids decreased, that is, the number of double bonds in the phospholipid decreased without a marked variation in the percentages of unsaturated fatty acids. Concomitantly, the percentage of fatty acids containing 16 carbon atoms increased, while that of fatty acids with 18 carbon atoms decreased. Since phosphatidylethanolamine is a dominant phospholipid in Drosophila, these changes probably contribute to keeping the homeoviscosity of the cellular membranes in a manner different to that in phosphatidylcholine-rich membranes, thereby increasing cold tolerance.

Depressive symptoms estimated by the Beck Depression Inventory (BDI) were examined in winter and summer in a total of 242 Japanese adults staying less than 2 years or longer than 10 years in Stockholm, where the length of daylight changes dramatically throughout the winter and summer seasons. In spite of the difference in the period of residency, both groups of subjects showed more mental and somatic depressive symptoms in the winter than in the summer. Moreover, the winter BDI score of long stayers was significantly higher than that of short stayers. Accordingly, our results suggest that, although seasonal mood variation is essentially produced by a chronobiological factor, Swedish lifestyle to which long stayers have been accustomed also influences the seasonal mood variation.

A risk factor is a characteristic which is associated with a greater than average probability of developing coronary disease. Raised serum cholesterol and hypertension are two such factors. Intervention studies conducted to confirm the risk factor hypothesis have shown that reduction of serum cholesterol and essential hypertension may be associated with a small decreased CHD incidence, however there were almost as many deaths due to coronary disease in the intervention groups as in the control groups. These findings suggest that our approach to risk factor intervention may be a misguided attempt which needs modification. It is possible that the major risk factors develop in an attempt of our body to adapt to environmental factors such as increased intake of salt, saturated fat and cholesterol, physical inactivity, increased intake of calories and obesity and stress. Smoking may be the result of social changes. Since the body has to modify its metabolic mechanism depending upon the factor to which it adapts, development of hyperlipidemia and hypertension may be protective mechanisms of the body which it has developed while fighting against environmental factors. Reduction of major risk factors by drug therapy may mean that we are trying to prevent the body, fighting environmental factors. Thus our approach to control of the major risk factors should be to treat the causative environmental factors or alter the lifestyle.(ABSTRACT TRUNCATED AT 250 WORDS)

In the summer of 1950, 1963, 1966 and 1973, repeated surveys were carried out on thermal conditions in various industries. Meanwhile technical innovations began to take hold gradually in Japan, causing, in major industries with hot work places, attenuation of heat exposure during work and reduction of the energy expenditure of workers by the replacing of heavy muscular work with machines. Comparison of data of the 1950s, 1960s and 1970s disclosed appreciable improvement of the thermal conditions in major industries which could be attributed to technical progress in recent years. An examination was made of the propriety of the existing legal provision on permissible threshold limit, of 37 degrees C in the coal mine in Japan. Experiments were conducted to investigate changes in some physiological functions and subjective feeling of coal miners during moderate muscular work in a hot and humid experimental gallery. The experimental results seemed to suggest that 34 degrees C of dry bulb air temperature might be a considerably severe condition for coal miners, even in cases of intermittent exposure or continuous exposure with rather frequent work intervals, working under conditions of high humidity and low air velocity at a moderate work rate.

Ventilatory response to CO2 in the Ama (Kachido) was determined by the CO2 rebreathing method in the beginning (March) and during (September) harvest season. It was found that mean slopes of the ventilatory response curve in March and September were 0.76 and 0.73 liters/(min.m2.mmHg), respectively, this difference being insignificant.