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1.
Alzheimers Dement ; 19(9): 3848-3857, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36960685

RESUMO

INTRODUCTION: Women are more vulnerable to Alzheimer's disease (AD) than men. The entorhinal cortex (EC) is one of the earliest structures affected in AD. We identified in cognitively intact elderly different molecular changes in the EC in relation to age. METHODS: Changes in 12 characteristic molecules in relation to age were determined by quantitative immunohistochemistry or in situ hybridization in the EC. They were arbitrarily grouped into sex steroid-related molecules, markers of neuronal activity, neurotransmitter-related molecules, and cholinergic activity-related molecules. RESULTS: The changes in molecules indicated increasing local estrogenic and neuronal activity accompanied by a higher and faster hyperphosphorylated tau accumulation in women's EC in relation to age, versus a mainly stable local estrogenic/androgenic and neuronal activity in men's EC. DISCUSSION: EC employs a different neurobiological strategy in women and men to maintain cognitive function, which seems to be accompanied by an earlier start of AD in women. HIGHLIGHTS: Local estrogen system is activated with age only in women's entorhinal cortex (EC). EC neuronal activity increased with age only in elderly women with intact cognition. Men and women have different molecular strategies to retain cognition with aging. P-tau accumulation in the EC was higher and faster in cognitively intact elderly women.


Assuntos
Doença de Alzheimer , Córtex Entorrinal , Masculino , Humanos , Feminino , Idoso , Doença de Alzheimer/genética , Envelhecimento
2.
Sci Total Environ ; 862: 160835, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502985

RESUMO

The imbalance between the water supply and demand in arid and semiarid regions is becoming increasingly serious due to global warming and human activities. It is of great significance to reveal the variation characteristics of runoff and its main controlling factors for the sustainable management of regional water resources. However, few previous studies have considered the integrated effects of multiple control factors on runoff variation at different periodic scales. We collected meteorological and hydrological data from 1960 to 2019 in the Huangshui watershed and explored the correlation degree between runoff and regional environment factors such as precipitation (P), potential evaporation (ET0), mean temperature (T), normalized difference vegetation index (NDVI). The wavelet coherence indicates that there was a high degree of positive phase consistency between runoff changes and P, ET0, T and NDVI at an approximately 12-month period scale, with lag times of approximately 1, 2, 1 and 0 months, respectively. The P was the single factor most closely related to runoff, and its combined with ET0 dominated the runoff change during the whole study period. The Budyko frame combined with elastic coefficient analysis showed that the climate change were the main reasons for the increase in annual runoff in change period I (1981-1990), and changes in the underlying surface due to human activities and vegetation variation was the main reason for the decrease in runoff in change period II (1991-2019). The wetter climate brought more rainfall input but this did not make runoff appear an obvious upward trend. Therefore, for alpine regions with sensitive and fragile ecological environment, the balance between human water consumption, vegetation ecological water demand, and precipitation should be weighed. The combination of wavelet coherence analysis and Budyko framework is helpful to better determine the potential driving factors of regional runoff change.


Assuntos
Monitoramento Ambiental , Movimentos da Água , Humanos , Recursos Hídricos , Abastecimento de Água , Mudança Climática , China
3.
Comput Intell Neurosci ; 2020: 8842390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33273902

RESUMO

The detection performance of high-frequency surface-wave radar (HFSWR) is closely related to the suppression effect of sea clutter. To effectively suppress sea clutter, a sea clutter suppression method based on radial basis function neural network (RBFNN) optimized by improved gray wolf optimization (IGWO) algorithm is proposed. Firstly, according to shortcomings of the standard gray wolf optimization (GWO) algorithm, such as slow convergence speed and easily getting into local optimum, an adaptive division of labor search strategy is proposed, which makes the population have abilities of both large-scale search and local exploration in the entire optimization process. Then, the IGWO algorithm is used to optimize RBFNN, finally, establishing a sea clutter prediction model (IGWO-RBFNN) and realizing the prediction and suppression of sea clutter. Experiments show that the IGWO algorithm has significantly improved convergence speed and optimization accuracy. Compared with the particle swarm algorithm with linear decreasing weight strategy (LDWPSO) and the GWO algorithm, the RBFNN prediction model optimized by the IGWO algorithm has higher prediction accuracy and has a better suppression effect on sea clutter of HFSWR.


Assuntos
Redes Neurais de Computação , Radar , Algoritmos
4.
Sci Rep ; 9(1): 12057, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427658

RESUMO

Recently, Goji berry (Lycium barbarum L.) has been extensively cultivated to improve the fragile ecological environment and increase the income of residents in Qinghai Province, northwestern China. However, few studies have focused on the physiological responses of Goji berry under salt stress and alkali stress. Gas exchange, photosynthetic pigments, and chlorophyll fluorescence were evaluated in response to neutral (NaCl) and alkali (NaHCO3) salt stresses. Nine irrigation treatments were applied over 30 days and included 0(Control group), 50, 100, 200, and 300 mM NaCl and NaHCO3. The results showed that salt and alkali stress reduced all the indicators and that alkali stress was more harmful to Goji berry than salt stress under the same solution concentrations. The salt tolerance and alkali resistance thresholds were identified when the index value exceeded the 50% standard of the control group, and threshold values of 246.3 ± 2.9 mM and 108.4.7 ± 2.1 mM, respectively, were determined by regression analysis. These results were used to identify the optimal water content for Goji berry. The minimum soil water content to cultivate Goji berry should be 16.22% and 23.37% under mild and moderate salt stress soils, respectively, and 29.10% and 42.68% under mild and moderate alkali stress soil, respectively.


Assuntos
Álcalis , Lycium/fisiologia , Salinidade , Tolerância ao Sal , Solo/química , Adaptação Biológica , China , Clorofila/química , Lycium/crescimento & desenvolvimento , Pigmentos Biológicos , Estresse Salino
5.
Ying Yong Sheng Tai Xue Bao ; 20(4): 791-7, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19565757

RESUMO

With two-year old seedlings of Hippophea rhamnoides and Shepherdia argentea as test materials, this paper studied their growth and photosynthetic characteristics under the stress of different concentration (0, 200, 400 and 600 mmol x L(-1)) NaCl. The results showed that the biomass and total leaf area per plant of H. rhamnoides and S. argentea seedlings decreased significantly with increasing NaCl concentration. Comparing with the control, the root/shoot ratio of H. rhamnoides and S. argentea seedlings under NaCl stress increased obviously, while the leaf mass per area (LMA) decreased slightly. When the NaCl concentration increased and the stress time prolonged, the net photosynthetic rate (P(n)), transpiration rate (T(r)), and stomatal conductance (G(s)) of H. rhamnoides and S. argentea seedlings declined markedly, the intercellular CO2 concentration (C(i)) increased after an initial decrease, whereas the water use efficiency (WUE) and stomatal limiting value (L(s)) decreased after an initial increase. The dynamic changes of G(s), C(i) and L(s) indicated that the decline of P(n) was mainly caused by the stomatal limitation in a short-term stress, and by non-stomatal limitation in a long-term stress. The poorer the salt tolerance of tree species and the higher the NaCl concentration, the earlier the transition from stomatal limitation to non-stomatal limitation would occur. As for H. rhamnoides, its morphological symptoms of salt injury appeared on the 10th day, and all of its seedlings were died on the 22th day under 600 mmol NaCl x L(-1) stress. In contrast, S. argentea could tolerate 600 mmol NaCl x L(-1) stress for above 30 days, illustrating that S. argentea, as an introduced tree species, had higher salt tolerance than H. rhamnoides, and could be planted widely in saline regions of China.


Assuntos
Elaeagnaceae/crescimento & desenvolvimento , Hippophae/crescimento & desenvolvimento , Fotossíntese/fisiologia , Plântula/crescimento & desenvolvimento , Cloreto de Sódio/farmacologia , Elaeagnaceae/fisiologia , Hippophae/fisiologia , Tolerância ao Sal , Plântula/fisiologia , Estresse Fisiológico
6.
Ying Yong Sheng Tai Xue Bao ; 14(6): 858-62, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12973983

RESUMO

With Li-6200 photosynthesis determination system and Li-1600 steaty state poro-meter, this paper studied the responses of Robinia pseudoacacia L. and Platycladus orientalis L. leaves' net photo-synthesis rate (Pn), carboxylation efficiency (CE), transpiration rate (Tr), water use efficiency (WUEL), stomata conductance (Cs), stomata resistance (Rs), intercellular CO2 concentration (Ci) and stomatal limitation (Ls) of Robinia pseudoacacia and Platycladus orientalis leaves to soil water content (SWC) in semi-arid region of Loess Plateau, and based on this, the soil water availability and its productivity of test woodland soils were graded and evaluated. The results showed that on Robinia pseudoacacia and Platycladus orientalis woodland, the SWC less than 4.5% and 4.0%, respectively belonged to "non-available water"; in the range of 4.5%-10.0% and 4.0%-8.5%, "low productivity and low efficiency water"; 10.0%-13.5% and 8.5%-11.0%, "middle productivity and high efficiency water"; 13.5%-17.0% and 11.0%-16.0%, "high productivity and middle efficiency water"; 17.0%-19.0% and 16.0%-19.0%, "middle productivity and low efficiency water"; and more that 19.0%, "low productivity and low efficiency water".


Assuntos
Clima Desértico , Robinia/crescimento & desenvolvimento , Solo , Árvores/crescimento & desenvolvimento , Água/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Transpiração Vegetal
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