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11.
Male genitalia show rapid and divergent evolution. It is rarely determined whether variation in male genital morphology influences
male reproductive success. Male damselflies possess a unique aedeagus with a re-curved head and spiny lateral processes, and
most females have two sperm storage organs, a spherical bursa copulatrix and a tubular spermatheca. Previous studies have
indicated that the re-curved head may remove bursal sperm, whereas the lateral processes remove spermathecal sperm. However,
we need more direct evidence of these functions. We compared sperm number in female sperm storage organs by interrupting copulation
to examine sperm removal by the male. In Calopteryx cornelia, males removed almost all bursal sperm but only partially removed spermathecal sperm. In contrast, females of Mnais pruinosa store sperm primarily in the bursa, and males removed only bursal sperm. To examine the functions of male spiny lateral processes,
we compared mating behaviour between control and experimental males from which we removed (cut) the lateral processes. In
C. cornelia, cutting of the lateral processes resulted in a decreased number of abdominal movements during copulation and no removal
of spermathecal sperm. The amount of bursal sperm removed during copulation also decreased in experimental males compared
to the unmanipulated males. However, in M. pruinosa, the experimental removal of male lateral processes did not decrease the abdominal movements and little affected the removal
of bursal sperm. Inter-specific differences between C. cornelia and M. pruinosa may be caused by variation in the strategies of female sperm storage. 相似文献
12.
Alexandre Marco da Silva Lucas Hubacek Tsuchiya Pablo Bettio Mendes Thiago Philipe de Camargo e Timo Artemio Cerd 《环境质量管理》2019,29(1):125-137
Soil erosion and the invasion of exotic plant species are major constraints to achieve sustainable development around the world. Currently, we find few products devoted concomitantly to combatting soil erosion as well as the establishment of unwanted exotic plants. In this paper, we introduce a new product, called herein a bioblanket, that protects the soil and impedes the establishment of exotic plant species. This product is of simple design, and to manufacture it, we use two biodegradable materials: jute tissue and grass wastes. We designed this product to combat soil erosion and the germination and establishment of new, unwanted, invasive plant species. In this paper, we describe our evaluation of how successful this product was in terms of improving the chemical attributes of soil. We also identified the product's potentialities and weaknesses by means of strengths, weaknesses, opportunities, and threats (SWOT) analysis. The bioblanket ameliorated the chemical attributes of the soil, as evidenced especially by the neutralization of acidity (8.5%) and aluminum toxicity (33%), and by an increment in nutrients concentration. We argue that after adequate treatment and management, the residues of plants that are normally considered unwanted materials can be transformed into a raw material to control the propagation of unwanted plant species, and concomitantly control soil erosion while improving the chemical conditions of the soil. The improvement of the soil chemical attributes was one of the main positive effects reported through the SWOT analysis. In addition, the SWOT analysis revealed some features that need improvement in future generations of the product, but we argue that these features do not impede the benefits for the use of the product in its present form. 相似文献
13.
Noriyoshi Kakuta Atsushi Shimizu Hironobu Ohkita Takanori Mizushima 《Journal of Material Cycles and Waste Management》2009,11(1):23-26
The dehydrochlorination behavior of plasticizer (DOP) and inorganic filler (CaCO3) contained in PVC samples and the properties of the activated carbons produced from those carbon residues have been investigated.
In the dehydrochlorination process, both additives contributed not only to a decrease in HCl yield but also to the prolonged
evolution of HCl. Part of the Cl species were observed to be stabilized as CaCl2 by reaction with calcium ions when CaCO3 was added. More than 80% of chlorine removal was achieved in all samples at 533 K. The use of potassium as an activation
agent led to the production of activated carbon with a specific surface area greater than 1000 m2/g at the low temperature of 1023 K and assisted also in the elimination of residual Cl species by the formation of KCl during
activation.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
14.
T. Meziane S. Y. Lee P. L. Mfilinge P. K. S. Shin M. H. W. Lam M. Tsuchiya 《Marine Biology》2007,150(6):1103-1113
Fatty acid compositions of the leaves of six species of mangroves were studied to ascertain their use as biomarkers for determining
the fate of mangrove organic matter in the habitat and as taxonomic tool. Mangrove leaves were collected from three locations
in the western Pacific Ocean: Moreton Bay (MB) (Australia), Hong Kong (China) and Okinawa (Japan). In MB, samples were collected
from two sites separated by 15 km: Logan River Estuary (LRE) and Jabiru Island. In addition, along the LRE, leaves were collected
from five stations at ∼2–3 km apart. Results show that the analysis of the entire fatty acid profiles of the mangrove leaves
is a promising taxonomic tool as the profiles of most species were sufficiently different to be separated in an non-metric
multidimensional scaling plot. In addition, geographically separated populations of the same species could also be identified
by their fatty acid profiles. In most cases, two non-ubiquitous groups of fatty acids dominated in the mangrove leaves: the
polyunsaturated 18:2ω6 and 18:3ω3 and the long chain fatty acids (≥24:0). With respect to the relative contributions of these
fatty acids, three groups of species were identified, in which one or both groups of fatty acids may potentially be used as
markers of the mangrove organic matter in the estuarine environment. 相似文献
15.
Yooko Tsuchiya Hisashi Abe Hisashi Shimogaki 《Journal of Material Cycles and Waste Management》2011,13(2):150-155
The leaching properties of trace elements in wood ash were examined to evaluate the safety of using woody biomass ash. Boron
and selenium were detected in high concentrations not only in ash collected from an electric furnace but also in combustion
ash from a small wood stove. As for the leaching of trace elements, the influence of calcium compounds on boron and selenium
in wood ash is proposed. The leaching of trace elements is enhanced when calcium carbonate is the calcium compound in ash,
although it is inhibited in the case of portlandite. There is little information in the literature that can be used to determine
the effective use of wood biomass ash, thus limiting the development of woody biomass for applications such as thermal power
generation. 相似文献
16.
17.
Kanjana Adulyanukosol Surasak Thongsukdee Takeshi Hara Nobuaki Arai Makoto Tsuchiya 《Marine Biology》2007,151(5):1887-1891
The seagrass beds at Muk Island and Talibong Island in Thailand are important areas for dugong (Dugong dugon) feeding and reproduction. We used opportunistic observations during aerial surveys to investigate dugong mating behavior
in shallow water areas near Talibong Island on three different days. The mating pattern was categorized by five stages: (1)
following: the male followed the female, (2) approaching and stimulating: the male approached and muzzled the female, (3)
pairing: both male and female swam in parallel, ventral to ventral or dorsal to dorsal side, (4) mounting: the male copulated
with the female, and (5) separating: the male and female swam in different directions. Parental care of calves included one
observation of a cow embracing her neonatal calf by the flippers. 相似文献
18.
Hyoe Takata Jian Zheng Keiko Tagami Tatsuo Aono Kazuhiro Fujita Shin-ichi Yamasaki Noriyoshi Tsuchiya Shigeo Uchida 《Environmental monitoring and assessment》2013,185(5):3645-3658
The sediment–water distribution coefficient, K d, is one of the most important parameters in radionuclide assessment models. In this study, we determined K ds of stable iodine (I) in estuarine and coastal regions. We studied 16 estuarine and coastal regions of Japan and obtained I data on water and sediments. Data on salinity, pH, dissolved organic carbon and dissolved oxygen in water, and organic carbon (OC) in sediments were also obtained as estuarine variables. Determined K ds of I in the Sagami River estuary decreased along the salinity gradient (salinity range, 0.1–33.8), indicating that salinity is one of the important factors controlling the K d values; however, when the K d values were compared among all the estuaries, the difference between minimum and maximum K d values varied by about two orders of magnitude in a narrow salinity range of 30.0–34.4. A significant correlation between K d value and OC content in sediments was observed in all the stations with a salinity of ≥30 except for stations in the Ishikari and Onga River estuaries. The exceptions are probably due to different sources of the sediments, which are explained by the results of relatively low I/OC ratios in sediments in those two estuaries, compared to the other estuaries. Thus, OC in sediments as well as salinity may be responsible for the variation of K ds of I in the estuarine and coastal regions. 相似文献