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61.

Objective

The authors have treated numerous children who have been injured by falling from bicycle-mounted child seats. Despite the greatly increased use of such seats, the understanding of their risk and the importance of helmet use remains alarmingly poor. The objective of this study was to confirm the risk of bicycle-mounted child seats and to evaluate the efficacy of helmets, seat belts, and back seat height in terms of preventing or mitigating contact-type head impacts that occur in falls from bicycle-mounted child seats.

Materials and methods

Biometrical dummy tests were performed to examine contact-type head injuries in falls from stationary bicycles. A bicycle with an anthropometric test dummy placed in a bicycle-mounted child seat was tipped over. Each test was repeated three times and three-dimensional acceleration was measured using accelerometer. Head Injury Criteria (HIC) were calculated and the respective influences of a helmet, a seat belt, and increased height of the back of the seat on such impacts were evaluated.

Results

Only helmets unequivocally lowered maximal acceleration and/or HIC values with statistical significance. The seat belt lowered HIC values as long as it was used with the high-back seat. Only when the dummy wore a helmet sitting in a high-back seat did the HIC show less than the threshold of 570 for three-year-old children. The HIC showed the lowest score of 161.5 when the dummy wore both a helmet and a seat belt sitting in a high-back seat.

Conclusions

Riders in bicycle-mounted child seats definitely have higher risks of contact-type head injuries. In transporting a child on a bicycle-mounted child seat, parents must use both a child-bicycle helmet and a high-back child seat at least; a seat belt is highly recommended as long as it is used with the other safety devices.

Impact on Industry

The bicycle-mounted child seat should have a high enough back and an appropriate seat belt to protect the head of the child from a contact-type injury.  相似文献   
62.
Journal of Material Cycles and Waste Management - Spent strongly acidic cation exchange resin was effectively used for the removal of trace concentration of fluoride ions. For this purpose, the...  相似文献   
63.
The results of a biodiversity monitoring program conducted in the Ogawa Forest Reserve and its vicinity, situated in a cool temperate region of Japan, identified three different patterns for species richness. Forests of the region are characterized by a mosaic of secondary deciduous stands of various ages scattered among plantations of conifers. The three different types of change in species richness observed in response to the stand age are as follows: Type I (butterflies, tube-renting bees and wasps, hoverflies, fruit flies, and longicorn beetles), the species diversity was highest in open areas, just after clear-cutting, decreasing with the stand age; Type II (mushrooms and mites associated with them), older stands showed greater diversity than younger stands; and, Type III (moths, oribatid mites, collembolas, carabid beetles, and ants), the number of species did not change greatly with the stand age, though ordination analysis revealed that there was variation in species compositions. These results indicate that combinations of stands of different ages, or heterogeneously arranged stands, can contribute to the maintenance of insect biodiversity at the landscape level.  相似文献   
64.
We examined the effects of tributyltin (TBT) on embryonic development, hatching success and sexual differentiation in Japanese medaka (Oryzias latipes). Embryos (within 8h after fertilization) were exposed to TBT in ovo via nanoinjection at concentrations of 0 (control), 0.16, 0.80, 3.96, 19.2 and 82.1 ng/egg. Embryonic survival, development and hatching were observed. Hatched fry were reared until 60 days when they sexually matured, and sexual differentiation was also examined by accordance of genetic and phenotypic sex, based on existence of DMY (a male determining gene in medaka) and secondary sex characteristics. As results, TBT caused a concentration-dependent mortality and impaired the embryonic development. However, no masculinization was detected at 60 dph medaka adults. Lowest observed effective concentration for inducing abnormal embryonic development was estimated to 0.16 ng/egg (ca. 160 ng/g egg).  相似文献   
65.
In the gasification of biomass, it is necessary to limit the amount of by-product tar and increase the yields of hydrogen (H2) and carbon monoxide (CO) (syngas). Therefore, we conducted gasification and reforming experiments on woody biomass using an electric tubular furnace, to evaluate the gas reforming and tar decomposition performance of a NiO/SBA-15 catalyst. As a result, we found that this catalyst is effective for H2 production. It is believed that the increase in H2 volume due to the catalyst occurs through a steam reforming reaction involving hydrocarbons, including methane (CH4), and the water-gas shift reaction. With respect to the influence of the gasifying agent on the reforming effect of the catalyst, the amount of generated carbon dioxide (CO2) and hydrogen (H2) increases because the shift reaction is promoted by supplying steam. On the other hand, it was inferred that the shift reaction rarely occurred because it approaches equilibrium by supplying O2. Furthermore, it is suggested that light aromatic hydrocarbons are decomposed by the catalyst.

Implications: The mesoporous silica catalyst NiO/SBA-15 was highly effective for H2 production and decomposition of light aromatic compounds in the gasification of woody biomass. In the catalyst reaction, supplying steam promoted H2 production. From thermodynamic analysis and discussion, it was also inferred that supplying O2 might prevent the water gas shift reaction. The results are useful for designing a process needed for rich H2 production and gas refining process for further use of syngas.  相似文献   

66.
Journal of Material Cycles and Waste Management - This study was conducted to clarify the fates of whole nitrogen cycle-associated microorganisms during laboratory-scale composting of cattle manure...  相似文献   
67.
Journal of Material Cycles and Waste Management - An efficient and environmentally benign biosorbent for Mo(VI) and W(VI) sequestration was developed by loading Zr(IV) ions onto Saponified Orange...  相似文献   
68.
This study aims at understanding flood risks and their impact on a community, in order to enhance communities’ resilience and adaptive capacity to these threats. It also investigates the possibility of looking at and handling risk from a resilience point of view. Therefore, while a conventional risk management process is employed in this study, social, physical, economic, and institutional dimensions of resilience are also included in order to grasp the extent of risks and the ways in which communities face, cope with, and recover from flooding. Findings showed that there was no significant difference in the perception of flood risk among household heads educated up to secondary school level, suggesting that they believe floods are purely natural events. Those with a higher level of education (high school and above) (82.7 % of respondents) were aware that flood disasters are the result of hazard and vulnerability combined. In addition, social dynamics were apparently strengthened by such disasters, which resulted in cohesion and mutual help following floods in some wards. Also, households with more sources of income and more savings appear to recover faster than others after a flooding event. With regard to governance and networks, greater efforts have to be made by local institutions to ensure basic functioning during and after disaster events and to invest more into risk reduction activities. However, further studies need to be conducted to clarify the understanding of the impact flood disasters have on the environment and community lives and livelihoods in general, as traditional coping strategies, although still practical, no longer suffice in the face of changes in climate and environment.  相似文献   
69.
70.
Reduction of dioxin emission by a quench reactor with lime spray was investigated in relation to post furnace formation pathways. Results showed that the quench reactor performed to supress post furnace reaction of precursor molecules to form selected congeners of PCDD and PCDF.  相似文献   
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