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1.
Neural Netw ; 161: 735-745, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36848827

RESUMO

This paper studies the energy scheduling for Denial-of-Service (DoS) attack against remote state estimation over multi-hop networks. A smart sensor observes a dynamic system, and transmits its local state estimate to a remote estimator. Due to the limited communication range of the sensor, some relay nodes are employed to deliver data packets from the sensor to the remote estimator, which constitutes a multi-hop network. To maximize the estimation error covariance with energy constraint, a DoS attacker needs to determine the energy level implemented on each channel. This problem is formulated as an associated Markov decision process (MDP), and the existence of an optimal deterministic and stationary policy (DSP) is proved for the attacker. Besides, a simple threshold structure of the optimal policy is obtained, which significantly reduces the computational complexity. Furthermore, an up-to-date deep reinforcement learning (DRL) algorithm, dueling double Q-network (D3QN), is introduced to approximate the optimal policy. Finally, a simulation example illustrates the developed results and verifies the effectiveness of D3QN for optimal DoS attack energy scheduling.


Assuntos
Algoritmos , Tecnologia sem Fio , Simulação por Computador , Cadeias de Markov , Fenômenos Físicos
2.
J Ethnobiol Ethnomed ; 16(1): 5, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000826

RESUMO

BACKGROUND: Due to their relative isolation, the previous studies of Monpa plant use were only conducted in north-east India. In October 2013, Mêdog County was no longer remote, thanks to completion of a highway into the county. This study of plant species used by the Monpa had three research objectives. These were (i) to identify and record local names and uses of plants in Mêdog County, (ii) to assess which of these were uses of endemic or near-endemic species within this part of the Indo-Burma biodiversity hotspot, and (iii) to assess how plant uses reflect socio-economic change in Mêdog County? METHODS: Field surveys were conducted in 12 villages of four townships in Mêdog County, Tibet, China. Two field visits were made. The first field trip was in November 2017 and the second field trip was in May 2018. We interviewed 64 key informants between 21 and 84 years old. Most of them were the village leaders and other local people who are knowledgeable about plants. After transect walks with knowledgeable local people, we used free listing, key informant interviews, and semi-structured interviews during the field work. Plants traditionally used by the Monpa were documented. Utilization frequency was used to assess the significance of each species, and the Cultural Importance index was used to estimate the cultural significance of the species in common. We also used the informant consensus factor (FIC) to determine the homogeneity of the informants' knowledge of medicinal plants. RESULTS: One hundred ninety-four plant species belonging to 82 families and 158 genera were recorded and collected. One hundred twenty-two species, primarily fruits, were food plants. Forty-five species were used as traditional medicines. This included highly valued species collected in alpine areas (Paris polyphylla) and brought to villages in Mêdog, which are at a lower altitude (between 728 and 1759 m a.s.l). Seven edible plant species were also used as herbal medicines. We also recorded 39 species used for other purposes in Monpa daily life. These included nine species that were used to make agricultural tools, five species for dyes and mordants, four species for timber, three species for fuelwood, four species for religious ritual use, three species for washing, two species for incense, two species for thatching, two species for fiber (rope and paper), two "calendar plants" were used to indicate seasons for agricultural purposes, two fish poison plant species, and one species were used as a tobacco substitute. Based on taxonomic insights and from studies elsewhere, we suggested that fiber species were under-reported (c. 14 species were used vs. one species reported used). Even though these plant species are rich and diverse, the use of endemic or near-endemic species was rarely recorded in previous studies. These species included Arenga micrantha (used for starch), Hornstedtia tibetica (fruits), Castanopsis clarkei (edible nuts) and Gnetum pendulum (edible nuts), Ophiorrhiza medogensis (vegetables), Derris scabricaulis (fish poison), Radermachera yunnanensis (agricultural tools), Litsea tibetana (seed oil), Dendrocalamus tibeticus (wine strainers and implements for administering medicine), Zanthoxylum motuoense (spices), Cinnamomum contractum (tobacco substitutes), Morus wittiorum (medicines), and Garcinia nujiangensis (funeral rituals). Despite the absence of roads until 2013 and the impression of "isolation," Monpa knowledge of plant use reflects three categories of change. Firstly, oral histories of plants used in Bhutan were also encountered by Monpa people after their migration from Bhutan to south-eastern Tibet. Secondly, a "slow change" through centuries of exchange of knowledge (for example of Chinese and Tibetan medical systems), seeds of introduced crops (finger millet (indigenous to Africa), maize (from Meso-America)), and experimentation and use of introduced medicinal plants (such as Datura stramonium, which originates from North America). Thirdly, "fast change" over the past decade. This is reflected in changes in traditional architecture and in rising commercial trade in selected plant resources such as Dendrobium orchid stems and Paris polyphylla rhizomes which are in demand in China's Traditional Chinese Medicine (TCM) markets). CONCLUSIONS: Monpa people in the south-eastern Tibet have detailed knowledge of the diverse plant resources. But that traditional knowledge is now faced with a crisis because of the modern socio-economic change. In addition, Monpa knowledge of plants reflects slower changes in knowledge as well. For example, Monpa ethnomedicine has been influenced by traditional Tibetan and Chinese medicine over a longer period in time. Overall, this study provides a deeper understanding of the Monpa peoples' knowledge on wild plants, including endemic and near-endemic species whose uses have not been previously recorded. Several of these narrowly distributed species, such as the fish poison Derris scabricaulis, could be the focus of further studies. Some wild edible plants may also have interesting dietary constituents which need in-depth studies. These detailed studies could enable the Monpa people to benefit from the use of their traditional plant-derived culture and therefore support the biodiversity conservation.


Assuntos
Etnicidade , Etnobotânica , Adulto , Idoso , Idoso de 80 Anos ou mais , Cultura , Etnobotânica/métodos , Frutas , Humanos , Entrevistas como Assunto , Medicina Tradicional/métodos , Pessoa de Meia-Idade , Plantas Medicinais , Inquéritos e Questionários , Tibet , Verduras , Adulto Jovem
3.
Plant Divers ; 42(6): 473-478, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34746526

RESUMO

The Naxi of Northwest Yunnan, China use medicinal plants to treat skin conditions related to traditional lifestyles in extreme environments. However, modernization endangers both the medicinal plants used to treat skin conditions and traditional knowledge. Therefore, investigation and documentation of the medicinal plants used and associated traditional knowledge is necessary. In this study, we conducted an ethnobotanical survey in 12 Naxi communities in Northwest Yunnan. For this purpose, we used semi-structured surveys to interview 840 informants from Naxi communities. We used informant consensus factor and use frequency as quantitative indices to evaluate the importance of medicinal plant species. A total of 161 medicinal plant species belonging to 69 families were documented. The highest informant consensus factor (ICF) values were recorded for skin nourishing (ICF = 0.849), frostbite and chapped skin (ICF = 0.833). These skin treatments are highly related to the environment and lifestyle of Naxi communities. The main active compounds of plants used to treat skin conditions in Naxi communities are known to have skin-treating properties. This study reveals that the skin conditions treated by the Naxi are associated with traditional medicine culture and social economic development. In addition, this study uses ethnobotanical indices to explain how skin condition treatments are linked to the natural environment of Naxi communities.

4.
Cereb Cortex ; 29(2): 838-851, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30535007

RESUMO

The von Economo neurons (VENs) are specialized large bipolar projection neurons with restricted distribution in the human brain, and they are far more abundant in humans than in non-human primates. However, VEN functions remain elusive due to the difficulty of isolating VENs and dissecting their connections in the brain. Here, we combined laser-capture-microdissection with RNA sequencing to describe the transcriptomic profile of VENs from human anterior cingulate cortex (ACC). Using pyramidal neurons as reference cells, we identified 344 genes with VEN-associated expression differences, including 215 higher and 129 lower expression genes. Functional enrichment and protein-protein interaction network analyses showed that these genes with VEN-associated expression differences are involved in VEN morphogenesis and functions, such as dendrite branching and axon myelination, and many of them are associated with human social-emotional disorders. With the use of in situ hybridization and immunohistochemistry assays, we validated four novel VEN markers (VAT1L, CHST8, LYPD1, and SULF2). Collectively, we generated a full-spectrum expression profile of VENs from human ACC, greatly enlarging the pool of genes with VEN-associated expression differences that can help researchers to understand the role of VENs in normal and disordered human brains.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/fisiologia , Giro do Cíngulo/fisiologia , Microdissecção/métodos , Neurônios/fisiologia , Análise de Sequência de RNA/métodos , Adulto , Giro do Cíngulo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios/patologia , Adulto Jovem
5.
J Ethnobiol Ethnomed ; 14(1): 74, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30486880

RESUMO

BACKGROUND: Bai people in the Dali Prefecture of Northwest Yunnan, China, have a long history of using plant extracts to dye their traditional costumes and maintain this culture for posterity. However, the development of modern technology, while vastly improving the dyeing efficiency, is also replacing indigenous knowledge which threatens the indigenous practice, causing the latter disappearing gradually. This study sought to examine the indigenous knowledge of plants used for textile dyeing in Bai communities, so as to provide a foundation for their sustainable development. METHODS: We conducted a semi-structured interview among 344 informants (above age 36) selected through a snowball sampling method. Free lists and participant observation were used as supplementary methods for the interviews. Three quantitative indicators (informant consensus factor [ICF], use frequency, and cultural importance index [CI]) were used to evaluate the indigenous knowledge of the dye-yielding plants. RESULTS: Twenty-three species belonging to 19 plant taxonomic families were used for dye by Bai communities. We summarized them into four life forms, eight used parts, five colors, three processing methods, and four dyeing methods. Among them, Strobilanthes cusia (Nees) O. Kuntze was the most traditional dyeing plant and has an important cultural value. Location, age, and gender were found to have a significant effect on indigenous knowledge, and the dyeing knowledge was dynamic and influenced by social factors. CONCLUSIONS: Diverse plant resources and rich indigenous knowledge of textile dyeing persist at settlements of Bai communities in Dali Prefecture. However, high labor costs and thinning market of traditional products that use plant dye cause repulsion toward traditional practice. To that, a good income in other profession attracts indigenous people to shift from their tradition of making plant-based dye and associated cultural systems at risk of extinction. More research for market development for products that use plant-based dye is necessary for the conservation of this valuable knowledge and biodiversity protection in Bai communities.


Assuntos
Corantes , Conhecimento , Plantas , Têxteis , Adulto , Idoso , Idoso de 80 Anos ou mais , Biodiversidade , China/etnologia , Etnobotânica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Artigo em Inglês | MEDLINE | ID: mdl-25832559

RESUMO

A survey of 2-acetyl-4-tetrahydroxybutylimidazole (THI) and 4-methylimidazole (4-MeI) concentrations in caramel colours, vinegar and beverages from the Chinese market were performed by ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). In total, 117 samples, 78 caramel colour samples, 23 vinegar samples and 16 beverage samples, were investigated. The results indicated that 4-MeI was found in all samples. THI was found in a part of the samples and also the level range was lower compared to 4-MeI. In caramel colour samples, the concentration level range of THI was 1.0-74.3 mg/kg and of 4-MeI was 1.5-1291.8 mg/kg. In vinegar samples, the concentration level range of THI was 13.3-119.2 µg/L and for 4-MeI 111.2-2077.8 µg/L. In beverage samples, THI was only found in two samples and the concentration level range of 4-MeI was 10.8-307.1 µg/L. THI and 4-MeI levels in vinegar and beverages were rather low compared with those in caramel colour samples. These observations can be helpful for evaluating individual exposure to THI and 4-MeI from caramel colours, vinegar and beverages in China.


Assuntos
Bebidas/análise , Carboidratos/química , Carcinógenos/análise , Condimentos/análise , Contaminação de Alimentos , Imidazóis/análise , Ácido Acético/química , Ácido Acético/economia , Ácido Acético/normas , Bebidas/economia , Bebidas/normas , Carboidratos/normas , China , Cromatografia Líquida de Alta Pressão , Condimentos/economia , Condimentos/normas , Inspeção de Alimentos/métodos , Guias como Assunto , Limite de Detecção , Reação de Maillard , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
7.
Zhonghua Gan Zang Bing Za Zhi ; 22(10): 731-4, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25496860

RESUMO

OBJECTIVE: To compare the abilities of transient elastography (TE) versus real-time tissue elastography (RTE) for assessing liver fibrosis in patients with chronic liver disease. METHODS: Ninetytwo patients with chronic liver disease were enrolled in the study, and included 77 cases of chronic hepatitis B, 4 cases of chronic hepatitis C, 4 cases of autoimmune liver disease, 2 cases of primary biliary cirrhosis, I case of abnormal bile duct development, and 4 cases of unknown etiology.All patients were assessed by both TE and RTE in a single day.The correlation coefficient of liver fibrosis level and the receiver operating characteristic (ROC) curve of S more than 2 and =4 of TE and RTE were determined.The values were compared using findings fiom pathological analysis as reference. RESULTS: The correlation coefficient of liver fibrosis level was significantly higher for TE (r =0.755, 95% CI:0.651-0.831, P =0.000) than for RTE (r=0.481, 95% CI:0.306-0.624, P =0.000) (Z=3.07, P =0.002).The areas under the ROC curves for S more than 2 and =4 were 0.903 and 0.740 for TE and 0.915 and 0.786 for RTE, respectively, indicating that the performance of TE was superior to that of RTE. CONCLUSION: TE was superior to RTE for assessment of liver fibrosis.


Assuntos
Hepatite B Crônica/diagnóstico por imagem , Hepatite C Crônica/diagnóstico por imagem , Cirrose Hepática Biliar/diagnóstico por imagem , Doenças Autoimunes , Técnicas de Imagem por Elasticidade , Humanos , Curva ROC
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(5): 412-5, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-24985383

RESUMO

OBJECTIVE: To investigate the levels of organophosphorus pesticides (OPPs) in animal foods and to assess the diet exposure risk of OPPs to Chinese population. METHODS: 115 samples, including pork, beef, mutton, chicken, fish, eggs, and milk were collected from 13 provinces in China, were analyzed by dual gas chromatography-dual pulsed flame photometry (GC-PFPD) for the contamination of 58 organophosphorus pesticide residues including their metabolites. The cumulative exposure assessment and high-end exposure assessment were used to assess the diet exposure risk of OPPs to Chineses population. RESULTS: The contamination levels of OPPs in animal foods were in the range of not detected (ND)-0.343 mg/kg, and the total detection rate was 37.4% (43/115). OPPs were frequently detected in samples of milk, fish and pork compared with other animal foods with the detection rate of 12/19, 9/16 and 7/16, respectively. The cumulative exposure amount of 10 OPPs to Chinese population was 0.12 µg×kg(-1)·d(-1), which accounted for 7.29% of the ADI. CONCLUSION: The residue levels of OPPs were low in animal food in the surveyed areas in China with some banned individual OPPs, such as methamidophos and monocrotophos, were detected. The dietary exposure risk of OPPs raised by the intake of animal foods in surveyed areas of China was low.


Assuntos
Ração Animal , Contaminação de Alimentos , Carne , Resíduos de Praguicidas , Animais , Bovinos , China , Cromatografia Gasosa , Dieta , Ovos , Alimentos , Leite , Compostos Organofosforados , Compostos Organotiofosforados , Praguicidas , Ovinos , Suínos
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