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1.
J Environ Manage ; 358: 120907, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657410

RESUMO

The rapid transition of agricultural systems substantially affects residential and industrial land use systems in rural areas, often generating spatiotemporal trade-offs between residential and industrial functions and producing considerable ecological impacts, which has thus far not been well understood. We conduct an indicator-based assessment of transitioning agriculture systems, and then links the transitioning agricultural systems to trade-offs between residential and industrial functions from 2005 to 2020 by using a case study-the metropolitan suburbs of Beijing, China. Also, the associated ecological impacts of the trade-offs are characterized based on the calculation of the ecological quality index (EQI) and ecological contribution rate. The results show that trade-offs between residential and industrial functions in the metropolitan suburbs have gradually adapted to the different agricultural systems in transition, which can be characterized by increasing industrial function as well as declining residential function, together with the diversification of land use into a mixed pattern. Additionally, along with the transitioning process comes a U shape of the ecological quality curve, which indicates that relentless industrial sprawl into regions where the agricultural system has a low capacity for technology, as well as decay in rural areas attributed to a rural exodus and industrial decline in semi-subsistence agricultural areas, even cause ecological degradation. In general, trade-offs between residential and industrial functions (especially for the non-agricultural production function) in rural areas could partially and temporally generate unfavorable ecological impacts, but it seems to be a favorable phenomenon to promote ecological quality in the long term. Therefore, to achieve rural sustainable planning, it is necessary for land use management to observe the trade-offs between residential and industrial functions while avoiding negative impacts, such as low-density land use patterns, disordered land use functions, and eco-environmental deterioration. Such effective strategies can contribute to the feasible implementation of policies aiming to achieve the compatible development of liveable residences, highly efficient industrial production, and eco-friendly operations in rural areas.


Assuntos
Agricultura , China , Indústrias , Conservação dos Recursos Naturais , População Rural , Ecologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-36982100

RESUMO

Land consolidation structure reflects land consolidation function, and studies about its spatio-temporal change and driving mechanism can serve for regional management and control land consolidation. At present, the analysis of regional differences, time changes, and driving factors of land consolidation type structure change is relatively lacking. Based on the data of provincial acceptance projects from 2000 to 2014, this paper analyzes the spatio-temporal change of rural land consolidation type structure in China, discusses the impact of relevant policies, and identifies the socio-economic driving factors in key regions by employing correlation analysis and the PLSR (partial least squares regression) method. The results showed that from 2000 to 2014, the proportional increase of land arrangement in China was significantly correlated with the proportional decrease of land reclamation (R2 = 0.93), and the proportional decrease of land development (R2 = 0.99) showed an obvious co-evolution pattern of increase and decrease; TILC (The area of land development/The area of land arrangement) decreased from 2.14 to 0.91 in 2002-2003. Since 2003, the dominant type of land consolidation in China has gradually changed from land development to land arrangement. However, the proportion of land development in QT (Qinghai-Tibet), JY (Jin-Yu), and FGH (Fujian-Guangdong-Hainan) areas is still more than 40%; the change of land consolidation type structure was influenced by policies, social and economic factors, such as urbanization rate, fixed assets investment, industrial proportion, and population density, and the regional difference was significant: the eastern section (JZS, Jiangsu-Zhejiang-Shanghai) is the industry proportion, the central area (HHAJ, Hunan-Hubei-Anhui-Jiangxi) is grain production and fixed assets investment, the western region (NW, Northwest China) has the urbanization rate, grain production, population density, and fixed assets investment. Land consolidation structure should be configured differentially in each region based on the identification of regional function orientation and comprehensive consideration of regional resource endowment and development needs and directions to improve the efficiency of land consolidation.


Assuntos
Desenvolvimento Econômico , Urbanização , China , Geografia , Densidade Demográfica
3.
Artigo em Inglês | MEDLINE | ID: mdl-36833709

RESUMO

The characteristic style of rural houses is an important manifestation of the historical and cultural values of rural areas and is the key focus of the implementation of the strategy for the construction of beautiful China and the revitalization of rural areas. Taking 17 villages in the Rongcheng of Shandong as an example, this article integrated multidimensional data, including geospatial data, survey data and socio-economic data, and constructed a suitable index system to evaluate the characteristic style of coastal rural houses in 2018 and put forward the characteristic style regionalization of coastal rural houses. The results show that the characteristic style of coastal rural houses can be measured by the overall village environment, coastal architectural value and traditional folk culture, among which the coastal architectural value is the most critical. Two villages scored over 60 points in the comprehensive evaluation, namely the Dongchu Island village and Dazhuang Xujia Community. Different dominant characteristic styles of rural houses were identified according to single-factor evaluation. Based on the evaluation results and factors such as location, nature, social economy and the status quo of protection and development management, characteristic styles of rural houses in the research area can be divided into four continuous areas: historical and cultural characteristics, folk customs and industrial development characteristics, natural scenery characteristics and folk customs characteristics. Combined with regional positioning and development planning, the construction direction of different regional types was defined, and then the protection and improvement measures of rural residential features were put forward. This study not only provides a certain basis for the evaluation, construction and protection of the characteristic features of coastal rural dwellings in Rongcheng City but also provides guidance for the implementation of rural construction planning.


Assuntos
Cultura , População Rural , Humanos , China , Cidades , Características Culturais
4.
Comput Intell Neurosci ; 2022: 8174674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785073

RESUMO

Aiming at the on-orbit safety problem of the two-dimensional tracking servo system for space, based on ant colony optimization (ACO) and expert systems, this paper proposes a fault diagnosis and handling strategy of the two-dimensional (2D) tracking servo system for space. Specifically, a fault library was established for the tracking servo system according to field observations. The ACO was called to optimize the classification of fault features. In addition, sensitivity and specificity were defined to evaluate the classification performance of the diagnosis rules found by the ant colony, aiming to suppress the redundant information in fault diagnosis, reduce the rows of the in-orbit codes, and improve the accuracy of in-orbit fault diagnosis. Meanwhile, the diagnosis information will be processed by the expert system, such that the servo system can work safely and stably in orbit, and less number of in-orbit computing resources were used. Simulation results show that the proposed strategy achieves highly precise and reliable diagnosis.


Assuntos
Simulação por Computador
5.
Transl Androl Urol ; 11(3): 336-347, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35402191

RESUMO

Background: At present, the incidence of obesity is increasing. Several studies have shown that obesity can reduce male fertility by affecting spermatogenesis and semen quality. Traditional Chinese medicine (TCM) has fewer side effects and stable efficacy in the treatment of related diseases. This study aimed to investigate the effect of Huaji Jianpi Decoction on the semen quality of high-fat diet-induced obese mice. Methods: The obese male mice model was constructed by using high-fat diet and the Huaji Jianpi Decoction was processed into an aqueous extract. Mice were allocated in the normal group (n=30) and five different treatment groups (n=50). Huaji Jianpi Decoction was applied in low-, medium- and high-dose [17.52 g/(kg·d), 35.04 g/(kg·d) and 70.07 g/(kg·d), respectively]. The body weight, body fat, testis wet weight, testis coefficient, and routine sperm parameters were detected and analyzed. Meanwhile, transmission electron microscope (TEM) was used to observe testis ultrastructure. reverse-transcription quantitative PCR (RT-qPCR) was used to measure the expression of tumour necrosis factor α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1). Results: Compared with normal mice (ND), the testis wet weight and testis coefficient of mice in the blank group were significantly decreased, while the number of mitochondria was observed to be decreased on testis ultrastructure examination, and apoptotic cells and germ cells in the spermatogenic tubules were shed. After Huaji Jianpi Decoction administration, the body fat and blood lipid levels of obese mice were decreased, the testis wet weight and testis coefficient were increased, and semen parameters were increased. Different doses of Huaji Jianpi Decoction could improve testicular weight, sperm density, sperm motility, forward motility, and total sperm motility. Huaji Jianpi Decoction could also downregulate TNF-α and MCP-1 expression and inhibit germ cell apoptosis to improve semen quality. Conclusions: Huaji Jianpi Decoction can improve the semen quality of high-fat diet-induced obese mice by reducing weight and lipid levels.

6.
AMB Express ; 11(1): 163, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34870775

RESUMO

As an important form of sustainable agriculture, rice-crab (Eriocheir sinensis) co-culture is rapid developing worldwide. However, the knowledge on the bacterial communities of the different components of the system is limited. In this study, we investigated the bacterial community structure in paddy soil and ditch sediment by using high-throughput sequencing technology. The results showed that compared with the ditch sediment, the content of NH4+-N in paddy soil decreased by 62.31%, and the content of AP (available phosphorus) increased by 172.02% (P < 0.05). The most abundant phyla in paddy soil and ditch sediment were Proteobacteria, Bacteroidetes and Chloroflexi, whose relative abundance was above 65%. Among the dominant genera, the relative abundance of an uncultured bacterium genus of Saprospiraceae and an uncultured bacterium genus of Lentimicrobiaceae in paddy soil was significantly lower than ditch sediment (P < 0.05). Alpha diversity indicated that the bacterial diversity of paddy soil and ditch sediment was similar. The bacterial community structure was affected by the relative abundance of bacteria, not the species of bacteria. Redundancy analysis (RDA) showed that the bacterial communities in paddy soil and ditch sediment were correlated with physicochemical properties. Our findings showed that the bacterial community structure was distinct in paddy soil and ditch sediment under rice-crab co-culture probably due to their different management patterns. These results can provide theoretical support for improving rice-crab co-culture technology.

7.
Sensors (Basel) ; 21(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208935

RESUMO

This paper proposes and implements a lightweight, "real-time" localization system (SORLA) with artificial landmarks (reflectors), which only uses LiDAR data for the laser odometer compensation in the case of high-speed or sharp-turning. Theoretically, due to the feature-matching mechanism of the LiDAR, locations of multiple reflectors and the reflector layout are not limited by geometrical relation. A series of algorithms is implemented to find and track the features of the environment, such as the reflector localization method, the motion compensation technique, and the reflector matching optimization algorithm. The reflector extraction algorithm is used to identify the reflector candidates and estimates the precise center locations of the reflectors from 2D LiDAR data. The motion compensation algorithm predicts the potential velocity, location, and angle of the robot without odometer errors. Finally, the matching optimization algorithm searches the reflector combinations for the best matching score, which ensures that the correct reflector combination could be found during the high-speed movement and fast turning. All those mechanisms guarantee the algorithm's precision and robustness in the high speed and noisy background. Our experimental results show that the SORLA algorithm has an average localization error of 6.45 mm at a speed of 0.4 m/s, and 9.87 mm at 4.2 m/s, and still works well with the angular velocity of 1.4 rad/s at a sharp turn. The recovery mechanism in the algorithm could handle the failure cases of reflector occlusion, and the long-term stability test of 72 h firmly proves the algorithm's robustness. This work shows that the strategy used in the SORLA algorithm is feasible for industry-level navigation with high precision and a promising alternative solution for SLAM.


Assuntos
Robótica , Algoritmos , Movimento (Física) , Movimento
8.
Appl Opt ; 57(34): F44-F49, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30645278

RESUMO

In this paper, we developed an auto-focus image quality evaluation function from the histogram feature function (HFF) of a high-speed camera. Based on this function, we then proposed a fast auto-focus search algorithm. We further demonstrated that the auto-focus image quality evaluation function we proposed requires fewer computational resources, while providing a more effective focusing area and more moderate sensitivity, compared to the traditional evaluation function. In contrast to the traditional climbing method, our proposed fast auto-focusing search algorithm also can spot the focus point in a shorter time, effectively reducing the round trips of the focusing motor and improving the focusing accuracy.

9.
Plant Sci ; 199-200: 113-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23265324

RESUMO

Brassinosteroids (BRs) are steroid hormones that participate in multiple biological processes. In this paper, we characterized a classic rice mutant Fn189 (dwarf54, d54) showing semi-dwarf stature and erect leaves. The coleoptile elongation and root growth was less affected in Fn189 than wild-type plant by the exogenous application of eBL, the most active form of BRs. Lamina joint inclination assay and morphological analysis in darkness further showed that Fn189 mutant plant was insensitive to exogenous eBL. Through map-based cloning, Fn189 was found to be a novel allelic mutant of the DWARF 61 (D61) gene, which encodes the putative BRs receptor OsBRI1. A single base mutation caused the I834F substitution in the OsBRI1 kinase domain. Consequently, kinase activity of OsBRI1 was found to decrease dramatically. Taken together, the kinase activity of OsBRI1 is essential for brassinosteroids to regulate normal plant growth and development in rice.


Assuntos
Brassinosteroides/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Oryza/enzimologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos , Brassinosteroides/farmacologia , Mapeamento Cromossômico , Clonagem Molecular , Cotilédone/efeitos dos fármacos , Cotilédone/enzimologia , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Escuridão , Regulação da Expressão Gênica de Plantas/genética , Dados de Sequência Molecular , Mutação , Oryza/efeitos dos fármacos , Oryza/genética , Oryza/crescimento & desenvolvimento , Fenótipo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Plântula/efeitos dos fármacos , Plântula/enzimologia , Plântula/genética , Plântula/crescimento & desenvolvimento , Alinhamento de Sequência
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