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Two new 14-step and 16-step reduced mechanisms for methane-air combustion were systematically developed by assuming the quasisteady state for 26-28 species in the starting mechanism. A series of comparison between the reduced mechanisms and the starting mechanism was carried out with the emphasis on their capabilities in predicting [NO.sub.2] formation and ignition delay. The two reduced mechanisms successfully capture the complex behaviors of [NO.sub.2] formation, which depends on the characteristic mixing time, pressure, and the contamination of hydrocarbon in air. The flame structure and [NO.sub.x] formation in diffusion flame were well predicted by the 16-step mechanism, while the 14-step showed less satisfactory performance on predicting prompt NO formation. The 16-step mechanism was shown accurate in predicting ignition delay over a wide range of equivalence ratio, temperature and pressure. The necessity of including [CH.sub.2]O, [C.sub.2][H.sub.6], [C.sub.2][H.sub.4], and [HO.sub.2] in the reduced mechanisms was discussed. [DOI: 10.1115/1.1360687]

Presents a study which discussed the development of reduced mechanisms for methane-air combustion and nitrogen dioxide formation. How the reduced mechanisms were developed; Assessment of the reduced mechanisms; Conclusions.

Compact cities are widely used in urban planning in Japan due to the following benefits: efficient land use, reduction in the transport network and reliance on mass transport, low emissions, etc. However, Compactness often means high density. In disaster-resistant Japan, whether the compact city form can effectively respond to disasters is needed further discussion. In the Kumamoto City Master Plan, 15 local hubs have been planned to promote the development of the compact city. In this study, 15 local hubs are selected as the research objects. Moreover, the entropy method was chosen to evaluate the disaster prevention capability. The results show that disaster risk is high and the disaster prevention ability is weak in the central urban area, which is likely to cause greater losses when the disaster occurs. The local hubs that are far away from the city centre also have the weak disaster prevention due to the lack of disaster prevention facilities, while some hub areas are more capable of disaster prevention despite the high risk of disasters. Therefore, in the post-disaster reconstruction plan, it is recommended making a focus on the low-risk and disaster resistant areas. At the same time, the cancellation of hubs with high risk and weak disaster prevention needs to be further discussed.

Bicycle is widely used in Japan by people of all age groups in daily usage, which may significantly ease traffic congestion. Responding to the cyclists increasing, the method to assess the quality of bicycle travel become necessary. Previous studies reported several approaches to obtain evaluation methods. However, cycleway evaluation in Japan is still far behind the evaluation methods developed in Europe or America. This paper concentrated on familiarizing readers with two methods for evaluating the quality of bicycle facilities and then presenting some proposals of cycleway evaluation in Japan referencing to these two methods. The first method, Bicycle Compatibility Index (BCI), is used to evaluate the road environment for cycling according to the road characteristics by statistical analysis. The second method, Bicycle Level of Service (BLOS), also represents an evaluation of safety for bicyclists. Both of the above methods offered equations of comfort and safety perceptions of bicyclists according to cycling environments. By introducing these methods in combination, this paper enables the readers to maximize the comparative advantages of both BCI and BLOS. The comparison includes sensitivity of variables and the development of both methods. Then we applied BCI and BLOS to evaluate the target roadways in Kumamoto, Japan.

Several clinical and experimental studies have demonstrated that traumatic brain injury (TBI) activates cascades of biochemical, molecular, structural, and pathological changes in the brain. These changes combine to contribute to the various outcomes observed after TBI. Given the breadth and complexity of changes, combination treatments may be an effective approach for targeting multiple detrimental pathways to yield meaningful improvements. In order to identify targets for therapy development, the temporally evolving pathophysiology of TBI needs to be elucidated in detail at both the cellular and molecular levels, as it has been shown that the mechanisms contributing to cognitive dysfunction change over time. Thus, a combination of individual mechanism-based therapies is likely to be effective when maintained based on the time courses of the cellular and molecular changes being targeted. In this review, we will discuss the temporal changes of some of the key clinical pathologies of human TBI, the underlying cellular and molecular mechanisms, and the results from preclinical and clinical studies aimed at mitigating their consequences. As most of the pathological events that occur after TBI are likely to have subsided in the chronic stage of the disease, combination treatments aimed at attenuating chronic conditions such as cognitive dysfunction may not require the initiation of individual treatments at a specific time. We propose that a combination of acute, subacute, and chronic interventions may be necessary to maximally improve health-related quality of life (HRQoL) for persons who have sustained a TBI., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Pramod Dash reports financial support was provided by National Institute of Neurological Disorders and Stroke. If there are other authors, they 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 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In recent years, lipids reused from urban wastewater materials have come to prominence as possible raw materials for biodiesel production. The present work investigated liquefied dimethyl ether (DME) for the lipid extraction of fat balls from sewage pumping stations. A response surface methodology (RSM) based on a Box-Behnken design (BBD) was utilized to optimize DME extraction parameters (sample size, velocity of liquefied DME, and DME/sample ratio). The maximum lipid yield was 65.2% under optimal DME extraction conditions (sample size 1 mm, velocity of liquefied DME 3.3 m/h, and DME/sample ratio 80 mL/g). Under the optimum conditions, the DME technique exhibited higher lipid recovery than that of mechanical shaking extraction (49.0%) or Soxhlet extraction (62.0%). The extracted lipids were converted into biodiesel, resulting in an approximately 35.2-46.2% biodiesel yield. Furthermore, the fatty acid methyl ester composition of the extracted lipids was characterized. These significant findings highlight the promising potential of fat balls as sustainable biodiesel feedstocks and provide valuable insight that will aid the development of better technology for lipid extraction., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Abstract The hippocampus plays a prominent role in learning and memory formation. The functional integrity of this structure is often compromised after traumatic brain injury (TBI), resulting in lasting cognitive dysfunction. The activity of hippocampal neurons, particularly place cells, is coordinated by local theta oscillations. Previous studies aimed at examining hippocampal theta oscillations after experimental TBI have reported disparate findings. Using a diffuse brain injury model, the lateral fluid percussion injury (FPI; 2.0 atm), we report a significant reduction in hippocampal theta power that persists for at least three weeks after injury. We questioned whether the behavioral deficit associated with this reduction of theta power can be overcome by optogenetically stimulating CA1 neurons at theta in brain injured rats. Our results show that memory impairments in brain injured animals could be reversed by optogenetically stimulating CA1 pyramidal neurons expressing channelrhodopsin (ChR2) during learning. In contrast, injured animals receiving a control virus (lacking ChR2) did not benefit from optostimulation. These results suggest that direct stimulation of CA1 pyramidal neurons at theta may be a viable option for enhancing memory after TBI.

The inspection and maintenance of transmission systems are necessary for their proper functioning. In this way, among the line's critical points are the insulator chains, which are responsible for providing insulation between conductors and structures. The accumulation of pollutants on the insulator surface can cause failures in the power system, leading to power supply interruptions. Currently, the cleaning of insulator chains is performed manually by operators who climb towers and use cloths, high-pressure washers, or even helicopters. The use of robots and drones is also under study, presenting challenges to be overcome. This paper presents the development of a drone-robot for cleaning insulator chains. The drone-robot was designed to identify insulators by camera and perform cleaning through a robotic module. This module is attached to the drone and carries a battery-powered portable washer, a reservoir for demineralized water, a depth camera, and an electronic control system. This paper includes a literature review on the state of the art related to strategies used for cleaning insulator chains. Based on this review, the justification for the construction of the proposed system is presented. The methodology used in the development of the drone-robot is then described. The system was validated in a controlled environment and in field experimental tests, with the ensuing discussions and conclusions formulated, along with suggestions for future work.