Study of hydrogen internal combustion engine vehicles based on the whole life cycle evaluation method

In order to better achieve the goal of low carbon emissions from vehicles, a whole life cycle assessment of hydrogen-fueled internal combustion engine vehicles has been conducted in recent years. Based on the study of hydrogen use around the world, we studied the emission and economic performance of hydrogen-fueled internal combustion engine vehicles from the beginning of hydrogen production to the end of use (Well-to-Wheel, WTW) based on the whole life cycle evaluation method. The results show that the overall environmental impact of hydrogen production by steam reforming of natural gas is the smallest, and that the rational use of "abandoned electricity" for hydrogen production from electrolytic water in the western part of China significantly reduces the overall environmental impact and the cost of hydrogen production. In the use phase, the emissions are less, which not only can meet the National 6 emission standard, but also can reach higher emission standard after adding exhaust gas recirculation (EGR). From the whole life cycle point of view, hydrogen-fueled internal combustion engine has a very good development prospect.Citation: Guo, P., Xu, J., Zhao, C., and Zhang, B. (2022). Study of hydrogen internal combustion engine vehicles based on the whole life cycle evaluation method. Trends in Renewable Energy, 8, 27-37. DOI: 10.17737/tre.2022.8.1.0013

Automated detection and classification of acute vertebral body fractures using a convolutional neural network on computed tomography

BackgroundAcute vertebral fracture is usually caused by low-energy injury with osteoporosis and high-energy trauma. The AOSpine thoracolumbar spine injury classification system (AO classification) plays an important role in the diagnosis and treatment of the disease. The diagnosis and description of vertebral fractures according to the classification scheme requires a great deal of time and energy for radiologists.PurposeTo design and validate a multistage deep learning system (multistage AO system) for the automatic detection, localization and classification of acute thoracolumbar vertebral body fractures according to AO classification on computed tomography.Materials and MethodsThe CT images of 1,217 patients who came to our hospital from January 2015 to December 2019 were collected retrospectively. The fractures were marked and classified by 2 junior radiology residents according to the type A standard in the AO classification. Marked fracture sites included the upper endplate, lower endplate and posterior wall. When there were inconsistent opinions on classification labels, the final result was determined by a director radiologist. We integrated different networks into different stages of the overall framework. U-net and a graph convolutional neural network (U-GCN) are used to realize the location and classification of the thoracolumbar spine. Next, a classification network is used to detect whether the thoracolumbar spine has a fracture. In the third stage, we detect fractures in different parts of the thoracolumbar spine by using a multibranch output network and finally obtain the AO types.ResultsThe mean age of the patients was 61.87 years with a standard deviation of 17.04 years, consisting of 760 female patients and 457 male patients. On vertebrae level, sensitivity for fracture detection was 95.23% in test dataset, with an accuracy of 97.93% and a specificity of 98.35%. For the classification of vertebral body fractures, the balanced accuracy was 79.56%, with an AUC of 0.904 for type A1, 0.945 for type A2, 0.878 for type A3 and 0.942 for type A4.ConclusionThe multistage AO system can automatically detect and classify acute vertebral body fractures in the thoracolumbar spine on CT images according to AO classification with high accuracy

Data from: Social call divergence in bats: a comparative analysis

Acoustic signals mediate important life history events in a variety of species, providing new vistas for understanding speciation. It has been proposed that animal acoustic signals undergo complex interactions among morphology, ecology, social pressure, and phylogenetic history. Yet, the relative importance of these factors in shaping acoustic divergence is rarely assessed within a comparative framework. Herein, we aim to investigate the key determinants of social call divergence across 31 bat species from 5 families. We compiled a wide data set on bat aggressive calls, body size, foraging habitats, foraging modes, climatic conditions, colony size, and phylogenetic components. We identified remarkable interspecific divergence versus within-species variation in aggressive vocalizations. Despite weak effects of ecological factors, colony size, body size, and phylogenetic components accounted for the majority of variation in call parameters among species. The colony size and body size played a major role in influencing spectral parameters, whereas phylogenetic relationships determined call duration and minimum frequency. Together, our findings constitute convincing evidence that sociality, morphological constraint, and phylogenetic constraint mold social call divergence in bats. This study expands our limited knowledge of the evolution of bat social calls, and highlights the importance of sociality in driving acoustic phenotype diversity

The oncological safety and long-term cosmetic effect of free dermal fat graft with epidermis removal for breast defect repair in breast conserving surgery

Background: Free dermal fat grafts (FDFG) are used for immediate breast defect repair in breast-conserving surgery (BCS), and have achieved satisfactory immediate postoperative cosmetic effects (Sawai et al., 2004) [1]. However, the oncologic safety and long-term cosmetic outcomes of these surgical procedures remain unknown. Therefore, t，in this study, we aim to investigate the oncological safety and long-term cosmetic outcomes of FDFG in patients with breast cancer. Methods: This matched retrospective case-control study included patients with non-special types of breast cancer who underwent FDFG for breast defect repair after BCS or BCS alone at two breast cancer research centers in Guangxi Province, China, from January 2016 to December 2019. The patients were divided into either the FDFG or BCS group. Control cases were screened using propensity score matching, and survival analysis and cosmetic evaluations were performed. Results: A total of 442 patients with breast cancer were included in the study. After 1:4 propensity score matching, 53 and 212 patients were included in the FDFG and BCS groups, respectively. The median follow-up time was 49.9 (9.0–76.0) months. The rate of local recurrence in the FDFG group (9.4 %) was significantly higher than that in the BCS group (1.9 %; p < 0.05). The total cosmetic evaluation score was significantly higher in the BCS group 18 months after surgery than in the FDFG group (p < 0.05). Conclusions: In this retrospective study, FDFG was significantly associated with an increased risk of local recurrence. Further prospective studies are required to confirm these results. No significant difference in long-term cosmetic effects were observed for FDFG than for BCS alone for immediate breast defect repair

The Impact of Land Use and Landscape Pattern on Ecosystem Services in the Dongting Lake Region, China

Ecosystem services (ES) are directly affected by land use and land cover changes (LUCC); however, the impacts of extended period LUCC on ES are poorly explored. Here, we mapped the 1998–2019 annual land use and land cover in the Dongting Lake Region (China) and explored the spatiotemporal evolution of LUCC and landscape patterns (i.e., composition, shape, and aggregation) and their relationship with ES, including carbon storage, gross primary production (GPP), water conservation capacity, and crop yield in the region. The results showed a significant increase in forest areas and impervious surfaces and a decrease in croplands and bare lands with spatial heterogeneity. Carbon storage was strongly correlated with forest, cropland, waterbody, impervious surface, and bare land, and there was a nonlinear relationship between landscape patterns and ES. The trade-offs and synergies (correlations) among ES varied considerably, with crop yield being significantly synergistic with carbon stocks, GPP, or GPP with carbon stocks. This study revealed the nonlinear relationship between landscape patterns and ES, and the mechanism of landscape characteristics on ES. The findings can provide scientific support for regional land use planning, ES regulation, and landscape optimization in the lake region

Supplementary material

The raw data and alternative linear mixed models are listed in the tables. The video is recorded via an infrared camera (SonyHDR- CX760PJ760, Japan) in the in temporary field station near the bat roost

Interfacial memristors in Al–LaNiO3 heterostructures

International audienceMemristive devices are promising circuit elements that enable novel computational approaches which go beyond the von-Neumann paradigms. Here by tuning the chemistry at the Al–LaNiO3 (LNO) interface, a metal–metal junction, we engineer good switching behavior with good electroresistance (ON–OFF resistance ratios of 100), and repeatable multiple resistance states. The active material responsible for such a behavior is a self-formed sandwich of an AlxOy layer at the interface obtained by grabbing oxygen by Al from LNO. Using aberration corrected electron microscopy and transport measurements, it is confirmed that the memristive hysteresis occurs due to the electric field driven O2− (or ) cycling between LNO (reservoir) and the interlayer, which drives the redox reactions forming and dissolving Al nanoclusters in the AlxOy matrix. This work provides clear insights into and details on precise oxygen control at such interfaces and can be useful for newer opportunities in oxitronics