Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
494
result(s) for
"Suzuki, Masakazu"
Sort by:
An accessible STEM editor customizable for various local languages
2019
Purpose
The purpose of this paper is to facilitate the spread of accessible e-books, especially ones of STEM much more in developing countries, an efficient/systematic scheme to localize tools for producing/reading them should be established. Furthermore, even in many advanced countries, Print-disabled people still do not have a good tool to write a content including technical notations such as mathematical formulas in their own local language. This work is aimed at giving a practical solution for those problems.
Design/methodology/approach
Here, multilingual support in a tool to produce accessible STEM contents and its new localization scheme are discussed.
Findings
It is shown that the accessible STEM-document editor can be customized easily for print-disabled people so that they can read and author a material including complicated technical notations in their own local language. The localization for Vietnamese and other various languages actually has been worked on.
Originality/value
The Vietnamese version was completed, and some prototype versions for the other languages were also given. It is expected that the software can contribute to improve STEM accessibility much more in many countries.
Journal Article
Molecular Machinery for Vasotocin-Dependent Transepithelial Water Movement in Amphibians: Aquaporins and Evolution
2015
Amphibians represent the first vertebrates to adapt to terrestrial environments, and are successfully distributed around the world. The ventral skin, kidney, and urinary bladder are important osmoregulatory organs for adult anuran amphibians. Water channel proteins, called aquaporins (AQPs), play key roles in transepithelial water absorption/reabsorption in these organs. At least 43 types of AQPs were identified in anurans; a recent phylogenetic analysis categorized anuran AQPs among 16 classes (AQP0-14, 16). Anuran-specific AQPa2 was assigned to AQP6, then was further subdivided into the ventral skintype (AQP6vs; AQPa2S), whose expression is confined to the ventral skin, and the urinary bladder-type (AQP6ub; AQPa2U), which is basically expressed in the urinary bladder. For the osmoregulatory organs, AQP3 is constitutively located in the basolateral plasma membrane of tight-junctioned epithelial cells. AQP6vs, AQP2 and/or AQP6ub are also expressed in these epithelial cells and are translocated to the apical membrane in response to arginine vasotocin, thereby regulating water absorption/reabsorption. It was suggested recently that two subtypes of AQP6vs contribute to cutaneous water absorption in Ranid species. In addition, AQP5 (AQP5a) and AQP5L (AQP5b) were identified from Xenopus tropicalis Gray, 1864, and AQP5 was localized to the apical membrane of luminal epithelial cells of the urinary bladder in dehydrated Xenopus. This finding suggested that AQP5 may be involved in water reabsorption from this organ under dehydration. Based on the hitherto reported information, we propose models for the evolution of water-absorbing/reabsorbing mechanisms in anuran osmoregulatory organs in association with AQPs.
Journal Article
Throughfall under a teak plantation in Thailand: a multifactorial analysis on the effects of canopy phenology and meteorological conditions
by
Tanaka, Nobuaki
,
Yoshifuji, Natsuko
,
Kumagai, Tomo’omi
in
Agriculture
,
Air temperature
,
Animal Physiology
2015
Valuable teak (Tectona grandis Linn. f.) plantations cover vast areas throughout Southeast Asia. This study sought to increase our understanding of throughfall inputs under teak by analyzing the abiotic and biotic factors governing throughfall amounts and ratios in relation to three canopy phenophases (leafless, leafing, and leafed). There was no rain during the brief leaf senescence phenophase in our study. Leveraging detailed field observations, we employed boosted regression tree (BRT) analysis to identify the primary controls on throughfall amount and ratio during each canopy phenophase. Whereas throughfall amounts were always dominated by rainfall magnitude (as expected), throughfall ratios were governed by a suite of predictor variables during each phenophase. The BRT analysis demonstrated that throughfall ratio in the leafless phase was most influenced (in descending order of importance) by air temperature, rainfall amount, maximum wind speed, and rainfall intensity. Throughfall ratio in the leafed phenophase was dominated by rainfall amount. The leafing phenophase was an intermediate case where rainfall amount, air temperature, and vapor pressure deficit were most important. Our results highlight the fact that throughfall ratios are differentially influenced by a suite of meteorological variables during each canopy phenophase. Abiotic variables, such as rainfall amount and air temperature, trumped leaf area index and stand density in their effect on throughfall ratio. The leafing phenophase, while transitional in nature and short in duration, has a detectable and unique impact on water inputs to teak plantations. Further work is needed to better understand the biogeochemistry of leaf emergence in teak plantations.
Journal Article
The impact of forest clear-cutting on soil temperature: a comparison between before and after cutting, and between clear-cut and control sites
by
Suzuki, Masakazu
,
Hashimoto, Shoji
in
biological activity in soil
,
Clear-cutting
,
Clearcutting
2004
Soil temperature is one of the most important factors governing biological activity in the soil. This study was conducted to investigate how forest clear-cutting changes soil temperature. Soil temperatures at 0.5, 1.0, 2.0, and 3.0m depths were measured in two neighboring forest watersheds (35°12′N, 140°06′E) in Chiba Prefecture, Japan, from 1994 to 2000. One watershed was clear-cut 5 years after the observations began. After clear-cutting, the annual mean soil temperature at 0.5, 1.0, 2.0, and 3.0m depths rose by about 2.2, 2.0, 1.7, and 1.4°C, respectively. The maximum respective soil temperatures rose by about 3.2, 3.0, 2.2, and 1.8°C. The minimum soil temperature rose slightly (<1°C). The range of temperatures increased by 3.0, 2.4, 1.6, and 1.4°C, respectively. In our study, forest clear-cutting raised maximum and average soil temperatures but hardly changed minimum soil temperature. This is probably because solar radiation dominated in the summer season and increased soil temperature; on the other hand, net long-wave radiation, and releases of latent and sensible heat from the soil surface, were predominant in the cool season.
Journal Article
Inter-annual variation in the response of leaf-out onset to soil moisture increase in a teak plantation in northern Thailand
by
Tanaka, Nobuaki
,
Yoshifuji, Natsuko
,
Igarashi, Yasunori
in
Animal Physiology
,
Annual variations
,
Biological and Medical Physics
2014
To understand the impact of inter-annual climate change on vegetation-atmosphere mass and energy exchanges, it has become necessary to explore changes in leaf-out onset in response to climatic fluctuations. We examined the response of leaf-out and transpiration onset dates to soil moisture in a teak plantation in northern Thailand based on a 12-year leaf area index and sap flow measurements. The date of leaf-out and transpiration onset varied between years by up to 40 days, and depended on the initial date when the relative extractable water in a soil layer of 0–0.6 m (
Θ
) was greater than 0.2 being consistent with our previous results. Our new finding is that the delay in leaf-out and transpiration onset relative to the initial date when
Θ
> 0.2 increases linearly as the initial date on which
Θ
> 0.2 becomes earlier. The delay spans about 20 days in years when
Θ
> 0.2 occurs in March (the late dry season)—much earlier than usual because of heavy pre-monsoon rainfalls—while there is little delay in years when
Θ
> 0.2 occurs in May. This delay indicates the influence of additional factors on leaf-out onset, which controls the delay in the response of leaf-out to soil moisture increase. The results increased our knowledge about the pattern and extent of the changes in leaf phenology that occur in response to the inter-annual climate variation in tropical regions, where, in particular, such research is needed.
Journal Article
The hagfish genome and the evolution of vertebrates
2024
As the only surviving lineages of jawless fishes, hagfishes and lampreys provide a crucial window into early vertebrate evolution
1
–
3
. Here we investigate the complex history, timing and functional role of genome-wide duplications
4
–
7
and programmed DNA elimination
8
,
9
in vertebrates in the light of a chromosome-scale genome sequence for the brown hagfish
Eptatretus atami
. Combining evidence from syntenic and phylogenetic analyses, we establish a comprehensive picture of vertebrate genome evolution, including an auto-tetraploidization (1R
V
) that predates the early Cambrian cyclostome–gnathostome split, followed by a mid–late Cambrian allo-tetraploidization (2R
JV
) in gnathostomes and a prolonged Cambrian–Ordovician hexaploidization (2R
CY
) in cyclostomes. Subsequently, hagfishes underwent extensive genomic changes, with chromosomal fusions accompanied by the loss of genes that are essential for organ systems (for example, genes involved in the development of eyes and in the proliferation of osteoclasts); these changes account, in part, for the simplification of the hagfish body plan
1
,
2
. Finally, we characterize programmed DNA elimination in hagfish, identifying protein-coding genes and repetitive elements that are deleted from somatic cell lineages during early development. The elimination of these germline-specific genes provides a mechanism for resolving genetic conflict between soma and germline by repressing germline and pluripotency functions, paralleling findings in lampreys
10
,
11
. Reconstruction of the early genomic history of vertebrates provides a framework for further investigations of the evolution of cyclostomes and jawed vertebrates.
A chromosome-scale genome assembly for the hagfish
Eptatretus atami
, combined with a series of phylogenetic analyses, sheds light on ancient polyploidization events that had a key role in the early evolution of vertebrates.
Journal Article
Characteristics of soil CO₂ efflux variability in an aseasonal tropical rainforest in Borneo Island
by
Ohashi, Mizue
,
Kumagai, Tomo'omi
,
Suzuki, Masakazu
in
Agricultural soils
,
Animal and plant ecology
,
Animal, plant and microbial ecology
2008
Although soil carbon dioxide (CO₂) efflux from tropical forests may play an important role in global carbon (C) balance, our knowledge of the fluctuations and factors controlling soil CO₂ efflux in the Asian tropics is still poor. This study characterizes the temporal and spatial variability in soil CO₂ efflux in relation to temperature/moisture content and estimates annual efflux from the forest floor in an aseasonal intact tropical rainforest in Sarawak, Malaysia. Soil CO₂ efflux varied widely in space; the range of variation averaged 17.4 μmol m⁻² s⁻¹ in total. While most CO₂ flux rates were under 10 μmol m⁻² s⁻¹, exceptionally high fluxes were observed sporadically at several sampling points. Semivariogram analysis revealed little spatial dependence in soil CO₂ efflux. Temperature explained nearly half of the spatial heterogeneity, but the effect varied with time. Seasonal variation in CO₂ efflux had no fixed pattern, but was significantly correlated with soil moisture content. The correlation coefficient with soil moisture content (SMC) at 30 and 60 cm depth was higher than at 10 cm depths. The annual soil CO₂ efflux, estimated from the relationship between CO₂ efflux and SMC at 30 cm depth, was 165 mol m⁻² year⁻¹ (1,986 g C m⁻² year⁻¹). As this area is known to suffer severe drought every 4-5 years caused by the El Nino-Southern Oscillation, the results suggest that an unpredictable dry period might affect soil CO₂ efflux, leading an annual variation in soil C balance.
Journal Article
Interannual variation in leaf expansion and outbreak of a teak defoliator at a teak stand in northern Thailand
by
Tanaka, Katsunori
,
Tantasirin, Chatchai
,
Suzuki, Masakazu
in
Animals
,
canopy
,
confidence interval
2011
The leaf area index (LAI) is a key factor affecting tree growth in forests. Following the outbreak of a defoliator, the LAI declines, serving as a useful indicator in forest management. In this study, daily radiative transmittance from above the canopy, which decreases exponentially with increasing LAI, was measured in a teak plantation (Tectona grandis L. f.) in northern Thailand from March through July in 2001-2008. Volumetric soil moisture was also measured at depths of 0.1, 0.2, 0.4, and 0.6 m. The negative logarithmic value of the ratio of daily downward solar radiation on the forest floor to that above the canopy (NLR; —ln[SbJ./5'|]), was calculated as an indicator of leaf flush and subsequent leaf expansion. The NLR data indicated that leaf expansion began in late March and continued to the beginning of May during all eight years (with the day the leaves began to expand defined as Z>B). In addition, the peak in NLR values (NLRP), corresponding to the lowest value of a 99% confidence interval, occurred in July. The day when NLR first reached NLRP was defined as Dp, which always occurred in June, 31-85 days after Z)B. The NLR indicated an increase in the population of Hyblaea puera (a teak defoliator) that was associated with greatly decreased leaf areas during two growth periods (DlrDP): the earliest DB-DP in 2001 and the second-earliest DB-DP in 2008. In almost all cases, soil moisture data indicated that leaf expansion occurred after increases in soil moisture at depths of 0.1-0.4 m even without increases at 0.6 m; in contrast, increases in shallow soil moisture (0.1-0.2 m) were insufficient to trigger leaf expansion at the stand level. Periods of soil drought at 0.1-0.4-m soil depths inhibited leaf expansion, resulting in prolongation of the interval between DB and Dp during those years in which the DB's occurred chronologically close to one another. Moreover, when drought did not limit leaf expansion, the DB-DP growth periods characterized by earlier DB's tended to be longer than those with later DB s.
Journal Article
Carbon allocation in a Bornean tropical rainforest without dry seasons
by
Nakagawa, Michiko
,
Kumagai, Tomo’omi
,
Kume, Tomonori
in
aboveground biomass
,
Biomass
,
Biomedical and Life Sciences
2013
To clarify characteristics of carbon (C) allocation in a Bornean tropical rainforest without dry seasons, gross primary production (GPP) and C allocation, i.e., above-ground net primary production (ANPP), aboveground plant respiration (APR), and total below-ground carbon flux (TBCF) for the forest were examined and compared with those from Amazonian tropical rainforests with dry seasons. GPP (30.61 MgC ha
−1
year
−1
, eddy covariance measurements; 34.40 MgC ha
−1
year
−1
, biometric measurements) was comparable to those for Amazonian rainforests. ANPP (6.76 MgC ha
−1
year
−1
) was comparable to, and APR (8.01 MgC ha
−1
year
−1
) was slightly lower than, their respective values for Amazonian rainforests, even though aboveground biomass was greater at our site. TBCF (19.63 MgC ha
−1
year
−1
) was higher than those for Amazonian forests. The comparable ANPP and higher TBCF were unexpected, since higher water availability would suggest less fine root competition for water, giving higher ANPP and lower TBCF to GPP. Low nutrient availability may explain the comparable ANPP and higher TBCF. These data show that there are variations in C allocation patterns among mature tropical rainforests, and the variations cannot be explained solely by differences in soil water availability.
Journal Article
Assessing raindrop impact energy at the forest floor in a mature Japanese cypress plantation using continuous raindrop-sizing instruments
by
Suzuki, Masakazu
,
Hotta, Norifumi
,
Nanko, Kazuki
in
Chamaecyparis obtusa
,
Continuous raindrop measurement
,
energy
2004
The raindrop size distribution of throughfall and open rainfall was monitored continuously during a rainfall event using laser raindrop-sizing instruments (LD gauges), in order to calculate the raindrop impact energy in a plantation of mature Japanese cypress (Chamaecyparis obtusa), where surface erosion at the forest floor had been a problem. Data from two rainfall events were analyzed. The LD gauges recorded qualitative raindrop size distribution, and the capture rate during each rainfall event was used to manipulate raindrop data quantitatively. Throughfall and open rainfall comparisons revealed several important differences. First, throughfall raindrops were fewer in number and larger in size than open rainfall drops. In one rainfall event, for example, throughfall raindrops were less than one-fifth as frequent as open rainfall raindrops; in addition, the maximum throughfall raindrop diameter was 6.35 mm compared to 3.31 mm for open rainfall raindrops. Second, throughfall raindrops that were larger than the largest open rainfall raindrops comprised 63.8% of the throughfall precipitation by volume. Third, total raindrop impact energy from throughfall was over twice that of open rainfall. Moreover, comparison of throughfall events implied that throughfall raindrops did not always have a uniform distribution between different events or among different periods of time in one rainfall event, in contrast to findings in previous studies which showed that throughfall raindrops had a uniform size distribution independent of rainfall intensity. It is possible that an abrupt transition of throughfall intensity from low to high changes the distribution of throughfall raindrops.
Journal Article