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1.
Ear Hear ; 39(5): 1015-1024, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29298164

RESUMEN

OBJECTIVES: Mental rotation is the brain's visuospatial understanding of what objects are and where they belong. Previous research indicated that deaf signers showed behavioral enhancement for nonlinguistic visual tasks, including mental rotation. In this study, we investigated the neural difference of mental rotation processing between deaf signers and hearing nonsigners using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI). DESIGN: The participants performed a block-designed experiment, consisting of alternating blocks of comparison and rotation periods, separated by a baseline or fixation period. Mental rotation tasks were performed using three-dimensional figures. fMRI images were acquired during the entire experiment, and the fMRI data were analyzed with Analysis of Functional NeuroImages. A factorial design analysis of variance was designed for fMRI analyses. The differences of activation were analyzed for the main effects of group and task, as well as for the interaction of group by task. RESULTS: The study showed differences in activated areas between deaf signers and hearing nonsigners on the mental rotation of three-dimensional figures. Subtracting activations of fixation from activations of rotation, both groups showed consistent activation in bilateral occipital lobe, bilateral parietal lobe, and bilateral posterior temporal lobe. There were different main effects of task (rotation versus comparison) with significant activation clusters in the bilateral precuneus, the right middle frontal gyrus, the bilateral medial frontal gyrus, the right interior frontal gyrus, the right superior frontal gyrus, the right anterior cingulate, and the bilateral posterior cingulate. There were significant interaction effects of group by task in the bilateral anterior cingulate, the right inferior frontal gyrus, the left superior frontal gyrus, the left posterior cingulate, the left middle temporal gyrus, and the right inferior parietal lobe. In simple effects of deaf and hearing groups with rotation minus comparison, deaf signers mainly showed activity in the right hemisphere, while hearing nonsigners showed bilateral activity. In the simple effects of rotation task, decreased activities were shown for deaf signers compared with hearing nonsigners throughout several regions, including the bilateral parahippocampal gyrus, the left posterior cingulate cortex, the right anterior cingulate cortex, and the right inferior parietal lobe. CONCLUSION: Decreased activations in several brain regions of deaf signers when compared to hearing nonsigners reflected increased neural efficiency and a precise functional circuitry, which was generated through long-term experience with sign language processing. In addition, we inferred tentatively that there may be a lateralization pattern to the right hemisphere for deaf signers when performing mental rotation tasks.


Asunto(s)
Encéfalo/fisiopatología , Sordera/fisiopatología , Lateralidad Funcional/fisiología , Reconocimiento Visual de Modelos/fisiología , Lengua de Signos , Adulto , Análisis de Varianza , Encéfalo/fisiología , Estudios de Casos y Controles , Femenino , Audición/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Personas con Deficiencia Auditiva , Valores de Referencia , Percepción Visual/fisiología , Adulto Joven
2.
Int J Biometeorol ; 62(8): 1389-1406, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29713863

RESUMEN

Mass landings of migrating white-backed planthopper, Sogatella furcifera (Horváth), can lead to severe outbreaks that cause heavy losses for rice production in East Asia. South-central China is the main infestation area on the annual migration loop of S. furcifera between the northern Indo-China Peninsula and mainland China; however, rice planthopper species are not able to survive in this region over winter. In this study, a trajectory analysis of movements from population source areas and a spatiotemporal dynamic analysis of mesoscale and synoptic weather conditions from 7 to 10 May 2012 were conducted using the weather research and forecasting (WRF) model to identify source areas of immigrants and determine how weather and topographic terrain influence insect landing. A sensitivity experiment was conducted with reduced topography using the WRF model to explain the associations among rainfall, topography, and light-trap catches of S. furcifera. The trajectory modeling results suggest that the source areas of S. furcifera immigrants into south-central China from 8 to 10 May were mainly southern Guangxi, northern Vietnam, and north-central Vietnam. The appearance of enormous catches of immigrant S. furcifera coincided with a period of rainstorms. The formation of transporting southerly winds was strongly associated with the topographic terrain. Additionally, the rainfall distribution and intensity over south-central China significantly decreased when topography was reduced in the model and were directly affected by wind circulation, which was associated with mountainous terrain that caused strong convection. This study indicates that migrating populations of S. furcifera were carried by the southwesterly low-level jets and that topographically induced convergent winds, precipitation, low temperatures, and wind shear acted as key factors that led to massive landings.


Asunto(s)
Distribución Animal , Hemípteros , Animales , China , Oryza , Lluvia , Vietnam , Viento
3.
Pest Manag Sci ; 78(11): 4975-4982, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36054519

RESUMEN

BACKGROUND: The fall armyworm (FAW) Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) invaded Myanmar and China in 2018 and greatly impacted agricultural production and ecosystem balance in these areas. FAW is a migratory insect, but its seasonal migration pattern between the two countries has been largely unknown. From 2019 to 2021, we monitored the seasonal migration of FAW in the China-Myanmar border area using a searchlight trap, assessed the reproductive development status of female migrants and traced the migratory routes by trajectory simulation. RESULTS: FAW moths were trapped by the searchlight trap in Lancang County (Yunnan, China) all year, with obvious seasonal differences in the number caught. There were small-scale persistent trapping peaks in spring and summer, and obvious peaks in autumn; only a small number of moths were trapped in winter. Examination of the ovaries of female moths collected in different seasons showed that most females had matured, indicating that the moths were migrating and did not take off from the local area. In the migration trajectory simulation, FAW mainly migrated from Myanmar to Southwest China in spring and summer and back to Myanmar in autumn. CONCLUSION: Our findings indicate that FAW migrates between China and Myanmar according to the monsoon circulation, which will help guide cross-border regional monitoring and management strategies against this pest. © 2022 Society of Chemical Industry.


Asunto(s)
Ecosistema , Animales , China , Femenino , Mianmar , Estaciones del Año , Spodoptera
4.
Insect Sci ; 28(3): 649-661, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32691947

RESUMEN

The fall armyworm Spodoptera frugiperda, an invasive insect pest native to the Americas, has established populations throughout eastern China. The North China Plain-a key corn-producing area in East China with a unique topography-was invaded by fall armyworm in 2019 and is seriously threatened by this migratory pest. However, the spatiotemporal extent of the migratory movements of fall armyworm from the North China Plain remains poorly understood. Using an air transport-based trajectory modeling approach that incorporates flight behavior, we simulated the potential nocturnal migration trajectories of fall armyworm from the North China Plain based on historical meteorological data from June to October of 2015-2019, and examined the night-time atmospheric conditions associated with their possible flights. The emigration patterns showed monthly variation in the main landing area and common migration direction. The displacement of newly emerged moths from the North China Plain was concentrated in the Northeast China Plain (including Liaoning, Jilin and Heilongjiang provinces) before late summer, after which they were most likely to undertake return flights to the south (especially into Hubei, Anhui and Hunan provinces). This southwest-northeast aerial migration corridor follows the topography of East China and is affected by the East Asian monsoon. These topographic-atmospheric conditions have resulted in the North China Plain becoming a key stopover for fall armyworm populations engaging in multigenerational long-distance migration across East China. These findings contribute to our knowledge of fall armyworm migration and will aid in the implementation of management and control strategies against this highly migratory agricultural pest.


Asunto(s)
Migración Animal , Spodoptera/fisiología , Animales , China , Clima , Simulación por Computador , Control de Insectos , Especies Introducidas , Control de Plagas , Estaciones del Año
5.
Neuroimage ; 49(1): 971-6, 2010 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19683582

RESUMEN

Long-term exposure to drug may alter the neural system associated with affective processing, as evidenced by both clinical observations and behavioral data documenting dysfunctions in emotional experiences and processing in drug addicts. Although many imaging studies examined neural responses to drug or drug-related cues in addicts, there have been few studies explicitly designed to reveal their neural abnormalities in processing non-drug-related natural affective materials. The present study asked abstinent heroin addicts and normal controls to passively view standardized affective pictures of positive, negative, or neutral valence and compared their brain activities with functional MRI. Compared to normal controls, addicts showed reduced activation in right amygdala in response to the affective pictures, consistent with previous reports of blunted subjective experience for affective stimuli in addicts. Furthermore, in two visual cortical areas BA 19 and 37, while the controls showed greater responses to positive pictures than to negative ones replicating literature findings, the addicts showed the opposite pattern. The results reveal a complex pattern of altered processing of non-drug-related affective materials in addicts showing both heightened and blunted neural responses in different brain regions and for different stimulus valence. The present study highlights the importance of brain imaging research on drug addicts' processing of affective stimuli in understanding disruptions in their emotion circuitry.


Asunto(s)
Afecto/fisiología , Dependencia de Heroína/psicología , Adulto , Amígdala del Cerebelo/fisiología , Encéfalo/fisiopatología , Dependencia de Heroína/fisiopatología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Estimulación Luminosa , Corteza Prefrontal/fisiopatología , Escalas de Valoración Psiquiátrica , Corteza Visual/fisiología , Adulto Joven
7.
Pest Manag Sci ; 76(2): 454-463, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31237729

RESUMEN

BACKGROUND: The fall armyworm (FAW), an invasive pest from the Americas, is rapidly spreading through the Old World, and has recently invaded the Indochinese Peninsula and southern China. In the Americas, FAW migrates from winter-breeding areas in the south into summer-breeding areas throughout North America where it is a major pest of corn. Asian populations are also likely to evolve migrations into the corn-producing regions of eastern China, where they will pose a serious threat to food security. RESULTS: To evaluate the invasion risk in eastern China, the rate of expansion and future migratory range was modelled by a trajectory simulation approach, combined with flight behavior and meteorological data. Our results predict that FAW will migrate from its new year-round breeding regions into the two main corn-producing regions of eastern China (Huang-Huai-Hai Summer Corn and Northeast Spring Corn Regions), via two pathways. The western pathway originates in Myanmar and Yunnan, and FAW will take four migration steps (i.e. four generations) to reach the Huang-Huai-Hai Region by July. Migration along the eastern pathway from Indochina and southern China progresses faster, with FAW reaching the Huang-Huai-Hai Region in three steps by June and reaching the Northeast Spring Region in July. CONCLUSION: Our results indicate that there is a high risk that FAW will invade the major corn-producing areas of eastern China via two migration pathways, and cause significant impacts to agricultural productivity. Information on migration pathways and timings can be used to inform integrated pest management strategies for this emerging pest. © 2019 Society of Chemical Industry.


Asunto(s)
Migración Animal , Spodoptera/fisiología , Animales , China , Mianmar , América del Norte , Zea mays
8.
Phytomedicine ; 79: 153330, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32932202

RESUMEN

BACKGROUND: Compound Dan Zhi tablet (DZT) is a commonly used traditional Chinese medicine formula. It has been used for the treatment of ischemic stroke for many years in clinical. However, its pharmacological mechanism is unclear. PURPOSE: The aim of the current study was to understand the protective effects and underlying mechanisms of DZT on ischemic stroke. METHODS: Fifteen representative chemical markers in DZT were determined by ultra-performance liquid chromatography coupled with tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). The protective effect of DZT against ischemic stroke was studied in a rat model of middle cerebral artery occlusion (MCAO), and the mechanism was further explored through a combination of network pharmacology and experimental verification. RESULTS: Quantitative analysis showed that the contents of phenolic acids, furan sulfonic acids, tanshinones, flavonoids, saponins and phthalides in DZT were calculated as 7.47, 0.788, 0.627, 0.531 and 0.256 mg/g, respectively. Phenolic acids were the most abundant constituents. Orally administered DZT (1.701 g kg-1) significantly alleviated the infarct size and neurological scores in MCAO rats. The network analysis predicted that 53 absorbed active compounds in DZT-treated plasma targeted 189 proteins and 47 pathways. Ten pathways were associated with anti-platelet activity. In further experiments, DZT (0.4 and 0.8 mg mL-1) markedly inhibited in vitro prostaglandin G/H synthase 1 (PTGS1) activity. DZT (0.4 and 0.8 mg mL-1) significantly inhibited in vitro platelet aggregation in response to ADP or AA. DZT (113 and 226 mg kg-1, p.o.) also produced a marked inhibition of ADP- or AA-induced ex vivo platelet aggregation with a short duration of action. DZT decreased the level of thromboxane A2 (TXA2) in MCAO rats. In the carrageenan-induced tail thrombosis model and ADP-induced acute pulmonary thromboembolism mice model, DZT (113 and 226 mg kg-1, p.o.) prevented thrombus formation. Importantly, DZT (113 and 226 mg kg-1, p.o.) exhibited a low bleeding liability. CONCLUSION: DZT protected against cerebral ischemic injury. The inhibition of TXA2 level, platelet aggregation and thrombosis formation might involve in the protective mechanism.


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Activación Plaquetaria/efectos de los fármacos , Trombosis/tratamiento farmacológico , Animales , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacocinética , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Masculino , Ratones Endogámicos ICR , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacología , Embolia Pulmonar/tratamiento farmacológico , Conejos , Ratas Sprague-Dawley , Comprimidos , Trombosis/inducido químicamente , Tromboxano A2/metabolismo
9.
Sci Rep ; 9(1): 18388, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31804548

RESUMEN

Sex ratio bias is common in migratory animals and can affect population structure and reproductive strategies, thereby altering population development. However, little is known about the underlying mechanisms that lead to sex ratio bias in migratory insect populations. In this study, we used Cnaphalocrocis medinalis, a typical migratory pest of rice, to explore this phenomenon. A total of 1,170 moths were collected from searchlight traps during immigration periods in 2015-2018. Females were much more abundant than males each year (total females: total males = 722:448). Sex-based differences in emergence time, take-off behaviour, flight capability and energy reserves were evaluated in a laboratory population. Females emerged 0.78 days earlier than males. In addition, the emigratory propensity and flight capability of female moths were greater than those of male moths, and female moths had more energy reserves than did male moths. These results indicate that female moths migrate earlier and can fly farther than male moths, resulting more female moths in the studied immigratory population.


Asunto(s)
Migración Animal/fisiología , Metabolismo Energético/fisiología , Vuelo Animal/fisiología , Mariposas Nocturnas/fisiología , Animales , Sesgo , Femenino , Larva/fisiología , Masculino , Oryza/parasitología , Reproducción/fisiología , Factores Sexuales , Razón de Masculinidad
10.
Insects ; 10(9)2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31540256

RESUMEN

The fall armyworm (FAW), native to the Americas, has rapidly invaded the whole of Southern China since January 2019. In addition, it can survive and breed in the key maize- and rice- growing area of the Yangtze River Valley. Furthermore, this pest is also likely to continue infiltrating other cropping regions in China, where food security is facing a severe threat. To understand the potential infestation area of newly-invaded FAW from the Yangtze River Valley, we simulated and predicted the possible flight pathways and range of the populations using a numerical trajectory modelling method combining meteorological data and self-powered flight behavior parameters of FAW. Our results indicate that the emigration of the first and second generations of newly-invaded FAW initiating from the Yangtze River Valley started on 20 May 2019 and ended on 30 July 2019. The spread of migratory FAW benefitted from transport on the southerly summer monsoon so that FAW emigrants from the Yangtze River Valley can reach northern China. The maize-cropping areas of Northeastern China, the Korean Peninsula and Japan are at a high risk. This study provides a basis for early warning and a broad picture of FAW migration from the Yangtze River Valley.

11.
Insects ; 9(3)2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30189679

RESUMEN

Many methods for trajectory simulation, such as Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT), have been developed over the past several decades and contributed greatly to our knowledge in insect migratory movement. To improve the accuracy of trajectory simulation, we developed a new numerical trajectory model, in which the self-powered flight behaviors of insects are considered and trajectory calculation is driven by high spatio-temporal resolution weather conditions simulated by the Weather Research and Forecasting (WRF) model. However, a rigorous evaluation of the accuracy of different trajectory models on simulated long-distance migration is lacking. Hence, in this study our trajectory model was evaluated by a migration event of the corn earworm moth, Helicoverpazea, in Texas, USA on 20⁻22 March 1995. The results indicate that the simulated migration trajectories are in good agreement with occurrences of all pollen-marked male H.zea immigrants monitored in pheromone traps. Statistical comparisons in the present study suggest that our model performed better than the popularly-used HYSPLIT model in simulating migration trajectories of H.zea. This study also shows the importance of high-resolution atmospheric data and a full understanding of migration behaviors to the computational design of models that simulate migration trajectories of highly-flying insects.

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