Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear...Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear.Methods:The effective components of green tea,mulberry leaf and corn silk were extracted and enriched.Mixture design of experiments was used to study the influences of different combinations on the cell viability and glucose uptake level of L6 myoblasts,so as to determine the optimal synergistic hypoglycemic combination.The possible hypoglycemic mechanism of the optimal synergistic combination was explored by cytotoxicity assay,glucose uptake assay,and western blot.Results:Three polyphenol enrichment fractions of the herbs,30%ethanol elution fraction of green tea(GT),50%ethanol elution fraction of mulberry leaf(ML)and 60%ethanol elution fraction of corn silk(CS)were obtained.The antioxidant activities of GT-30%,ML-50%and CS-60%were superior to those of crude extracts,and showed strong potential inα-amylase andα-glucosidase inhibition activities.The optimal synergistic combination of crude extracts G7(crude extract of green tea:crude extract of mulberry leaf:crude extract of corn silk=1:5:3),polyphenol enrichment fractions R3(GT-30%:ML-50%:CS-60%=1:7:1)and monomers X2(epigallocatechin gallate:morusin:formononetin=3:1:2)were selected,respectively.G7,R3,and X2 showed promoting effects on the cell viability and glucose uptake of L6 myoblasts within the detected concentration range.In addition,G7,R3,and X2 could increase the expression levels of p-PI3K/PI3K and p-Akt/Akt in L6 myoblasts,and promote the translocation of Glut4,but G7 and R3 showed more significant effects.Conclusion:The synergistic hypoglycemic effects of green tea,mulberry leaf and corn silk had the characteristics of multiple-components and multiple-targets with p-PI3K/PI3K,p-Akt/Akt and the translocation of Glut4 signal pathways involved.The three traditional herbs might have the potential to be combined used for the prevention and treatment of diabetes based on the synergistic hypoglycemic effects.展开更多
Maize(Zea mays L.) is an economically vital grain crop that is cultivated worldwide. In 2011, a maize foliar disease was detected in Lingtai and Lintao counties in Gansu Province, China. The characteristic signs and s...Maize(Zea mays L.) is an economically vital grain crop that is cultivated worldwide. In 2011, a maize foliar disease was detected in Lingtai and Lintao counties in Gansu Province, China. The characteristic signs and symptoms of this disease include irregular chlorotic lesions on the tips and edges of infected leaves and black punctate fruiting bodies in dead leaf tissues. Given favourable environmental conditions, this disease spread to areas surrounding Gansu. In this study, infected leaves were collected from Gansu and Ningxia Hui Autonomous Region between 2018and 2020 to identify the disease-causing pathogen. Based on morphological features, pathogenicity tests, and multilocus phylogenetic analysis involving internal transcribed spacer(ITS), 18S small subunit rDNA(SSU), 28S large subunit rDNA(LSU), translation elongation factor 1-alpha(TEF), and β-tubulin(TUB) sequences, Eutiarosporella dactylidis was identified as the causative pathogen of this newly discovered leaf blight. Furthermore, an in vitro bioassay was conducted on representative strains using six fungicides, and both fludioxonil and carbendazim were found to significantly inhibit the mycelial growth of E. dactylidis. The results of this study provide a reference for the detection and management of Eutiarosporella leaf blight.展开更多
To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of ef...To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(i.e.altered stress conditions)for the fractured core models and the vuggy core models have similar change patterns.The ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy reservoirs.Since each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and 1.Meanwhile,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was proposed.It is proved theoretically that the ESCP of CFVR generally varies between 0 and 1.Additionally,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial model.The concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the weakest.In general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs.展开更多
The study on the changes of stomatal sensitivity in relation to xylem ABA during periodical soil drying and the effect of leaf water status on the stomatal sensitivity has confirmed that xylem ABA concentration is a g...The study on the changes of stomatal sensitivity in relation to xylem ABA during periodical soil drying and the effect of leaf water status on the stomatal sensitivity has confirmed that xylem ABA concentration is a good indicator of soil water status around roots and the relation between xylem ABA concentration and predawn leaf water potential remained constant during the three consecutive soil drying cycles based on the slopes of the fitted lines. The sensitivity of stomata to xylem ABA increased substantially as the soil drying cycles progressed, and the xylem ABA concentration needed to cause a 50% decrease of stomatal conductance was as low as 550 nmol/L in the next two soil drying cycle, as compared with the 750 nmol/L ABA in the first cycle of soil drying. The results using the split_root system showed that leaf water deficit significantly enhanced the stomatal response to xylem ABA and the xylem ABA concentration needed to cause a 50% decrease in stomatal conductance was 2 to 4 times smaller in the whole_root_drying treatment than those in the semi_root_drying treatment. These results suggested that the sensitivity of stomata to xylem ABA concentration is not a fixed characteristic.展开更多
[Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. ...[Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. [Method] According to field test method, the effects of treatments with growth inhibitor at 0.5%, 1%, 1.5%and 2% on Eupatorium adenophorum were explored and the growth of other weeds was observed to research selectivity of plant inhibitor on the plant. [Result] The growth inhibitor had significant effects on ground parts of Eupatorium adenophorum. Specifical y, after 2 h, Eupatorium adenophorum was damaged seriously and the damage degree went worse upon inhibitor concentration. After 5 d, the control effect of the inhibitorreached 41.5% with concentration at 1.5%, reached 90.2% with the concentration at 1%, and 100% with the concentration at 1.5% and 2%. After 15 d, the control effect achieved 64.6%, 91.7%, 98.9% and 100% with concentrations at 0.5%, 1%, 1.5% and 2%. Stil , the effects of growth inhibitors on root system were limited. For example, new branches would grow from base part if the inhibitor con-centration is too low. On the other hand, the growth inhibitor is of sensitivity and selectivity, which would not hurt other plants. [Conclusion] It is feasible to rapidly control growth and development and even kil Eupatorium adenophorum based on plant sensitivity and it is proved that the growth inhibitor at 1.5% would considerably restrict and kil Eupatorium adenophorum. Therefore, the concentration of growth in-hibitors should be over 1.5%.展开更多
Soil structure and nutrient ingredient before and after shattering and returning sugarcane leaf as well as its technologies and methods were comparatively analyzed in this study to discuss the main reasons primarily,w...Soil structure and nutrient ingredient before and after shattering and returning sugarcane leaf as well as its technologies and methods were comparatively analyzed in this study to discuss the main reasons primarily,while the controlling technologies were proposed by combining cultivation,management and technical measures.展开更多
Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. ...Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. Three popular agricultural crops: Falen (Vigna unguiculata), Chickpea (Cicer arietinum), Arhor (Cajanus cajan) and two widely used plantation trees: Sada koroi (Albizia procera) and Ipil ipil (Leucaena leucocephala) were selected as bioassay species. Experiment was set on tray at room temperature 27℃. The effects of different doses of leaf litter extracts were compared to the control. Results suggest that leaf litters of E, camaldulesis induced inhibitory effects, It was also found that the effect depend on concentration of extract and litterfall, type of receiver species. Higher concentration of the materials had the higher effect and vice versa. Though all the bioassay species were suppressed some of them showed better performance. Vigna unguiculata, Cicer arietinum are recommended in agroforestry based on this present Experiment output. In mixed plantation, Leucaena leucochephala is a better choice while compared to Albizia procera.展开更多
The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and different...The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and differential scanning calorimetry(DSC).The water-cooled and aged alloy exhibits higher strength than the air-cooled and aged alloy;2.5%pre-stretching of tensile deformation exerts little effect on strength of water-cooled and aged alloy but increases that of air-cooled and aged one,and therefore the yield strength reduction rate due to slow quenching decreases from about 3.8%to about 1.0%,reducing quench sensitive effect.For the air-cooled alloy,pre-stretching increases the sizes ofη'strengthening precipitates but also increases their quantity and the ratio of diameter to thickness,resulting in enhanced strengthening and higher strength after aging.The reason has been discussed based on microstructure examination by TEM and DSC.展开更多
Spectral index methodology has been widely used in Leaf Area Index(LAI) retrieval at different spatial scales. There are differences in the spectral response of different remote sensors and thus spectral scale effect ...Spectral index methodology has been widely used in Leaf Area Index(LAI) retrieval at different spatial scales. There are differences in the spectral response of different remote sensors and thus spectral scale effect generated during the use of spectral indices to retrieve LAI. In this study, PROSPECT, leaf optical properties model and Scattering by Arbitrarily Inclined Layers(SAIL) model, were used to simulate canopy spectral reflectance with a bandwidth of 5 nm and a Gaussian spectral response function was employed to simulate the spectral data at six bandwidths ranging from 10 to 35 nm. Additionally, for bandwidths from 5 to 35 nm, the correlation between the spectral index and LAI, and the sensitivities of the spectral index to changes in LAI and bandwidth were analyzed. Finally, the reflectance data at six bandwidths ranging from 40 to 65 nm were used to verify the spectral scale effect generated during the use of the spectral index to retrieve LAI. Results indicate that Vegetation Index of the Universal Pattern Decomposition(VIUPD) had the highest accuracy during LAI retrieval. Followed by Normalized Difference Vegetation Index(NDVI), Modified Simple Ratio Indices(MSRI) and Triangle Vegetation Index(TVI), although the coefficient of determination R^2 was higher than 0.96, the retrieved LAI values were less than the actual value and thus lacked validity. Other spectral indices were significantly affected by the spectral scale effect with poor retrieval results. In this study, VIUPD, which exhibited a relatively good correlation and sensitivity to LAI, was less affected by the spectral scale effect and had a relatively good retrieval capability. This conclusion supports a purported feature independent of the sensor of this model and also confirms the great potential of VIUPD for retrieval of physicochemical parameters of vegetation using multi-source remote sensing data.展开更多
A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes...A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation.展开更多
Microorganisms are nutritious resources for various soil fauna.Although soil fauna grazing affects microorganism composition and decomposition rate,the responses of soil fauna and leaf litter decomposition to added mi...Microorganisms are nutritious resources for various soil fauna.Although soil fauna grazing affects microorganism composition and decomposition rate,the responses of soil fauna and leaf litter decomposition to added microorganism is little understood.In this study,in the coniferous and broad-leaved mixed forest of Tahe County in the northern Da Hinggan Mountains,China,three sampling sites(each has an area of 10 m2) were selected.The first two sites were sprinkled with 250 times(EM1) and 1000 times(EM2) diluted effective microorganism(EM) preparations evenly,and the third site was sprinkled with the same volume of water as a control site.The responses of soil fauna structure and leaf litter decomposition to EM treatment were conducted during three years.The results revealed that EM treatment resulted in significant increase of soil organic matter.The number of soil fauna in the EM1 and EM2 sites increased by 12.88% and 2.23% compared to the control site,and among them springtails and mites showed the highest increase.However,the groups of soil fauna in the EM1 and EM2 sites decreased by 6 and 9,respectively.And the changes in the diversity and evenness index were relatively complicated.EM treatment slowed the decomposition of broad-leaved litter,but accelerated the decomposition of coniferous litter.However,the decomposition rate of broad-leaved litter was still higher than that of coniferous litter.The results of this study suggested that the added microorganisms could help individual growth of soil fauna,and this method led to a change in the process of leaf litter decomposition.This paper did not analyze the activity of soil microorganisms,thus it is difficult to clearly explain the complex relationships among litter type,soil fauna and soil microorganisms.Further research on this subject is needed.展开更多
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation...Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.展开更多
Agropyron cristatum(2n=4x=28,PPPP)is a wild relative of common wheat which contains a large number of desirable genes that can be exploited for wheat improvement.Wheat–A.cristatum 2P alien translocation lines exhibit...Agropyron cristatum(2n=4x=28,PPPP)is a wild relative of common wheat which contains a large number of desirable genes that can be exploited for wheat improvement.Wheat–A.cristatum 2P alien translocation lines exhibit many desirable traits,such as small flag leaves,a high spikelet number and density,and a compact plant type.An agronomic trait evaluation and a genetic analysis were carried out on translocation lines and backcross populations of these lines carrying different translocation fragments.The results showed that a translocation fragment from 2PT-3(2PL)reduced the length of the flag leaves,while translocation fragments from 2PT-3(2PL)and 2PT-5(2PL(0.60–1.00))reduced the width of the flag leaves.A translocation fragment from 2PT-13(2PS(0.18–0.36))increased the length and area of the flag leaves.Translocation fragments from 2PT-3(2PL)and 2PT-8(2PL(0.86–1.00))increased the density of spikelets.Translocation fragments from 2PT-7(2PL(0.00–0.09)),2PT-8(2PL(0.86–1.00)),2PT-10(2PS),and 2PT-13(2PS(0.18–0.36))reduced plant height.This study provides a scientific basis for the effective utilization of wheat–A.cristatum translocation lines.展开更多
An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi (Albizia procera), Ipil ipil (L. leucocephala) and three agricultural crops Falen (Vigna ung...An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi (Albizia procera), Ipil ipil (L. leucocephala) and three agricultural crops Falen (Vigna unguiculata), Chickpea (Citer arietinum) and Arhor (Cajanus cajan) in the nursery of the Institute of Forestry and Environmental Sciences, Chittagong University, Bangladesh, in a Randomized Block Design. Results suggested that leaf litters ofL. leucocephala induced inhibitory effects on germination and growth of bioassay. It was also found that the effect depended on concentration of extract and litterfall, type of receptor species. Higher concentration of the materials had the higher effect and vice versa. Growth response of receptor crops varied with the variation of leaf litter application. The study revealed that application of low-dose leaf litter specially litter of 10 g·m^-2 had stimulating effect on shoot growth of C. arietinum, Vunguiculata and A. procera. While in all other cases significant inhibitory effect was observed and it was significantly increased with the increase of leaf litter application. However, the trend of inhibition was uneven with treatments. Root growth was found to be more affected than shoot growth.展开更多
Peanut (Arachis hypogaea L.) leaf aqueous extracts (PLAE) has been reputed to be a type of sleep-aid in China. To investigate the sedative effects and effect pathways of PLAE, rats (n = 31) were employed in two experi...Peanut (Arachis hypogaea L.) leaf aqueous extracts (PLAE) has been reputed to be a type of sleep-aid in China. To investigate the sedative effects and effect pathways of PLAE, rats (n = 31) were employed in two experiments and intragastrically administrated of (1) distilled water, PLAE (500 mg/kg body weight (BW)) and peanut stem aqueous extracts (PSAE, 500 mg/kg BW);(2) 0, 100 or 500 mg/kg BW of PLAE, respectively for at least 14 days. Six relevant neurotransmitters were measured finally. Experiment-1 (n = 16) results showed that the brain Lactate were significantly elevated (p < 0.05) in rat cerebrums after PLAE administrations, compared with Control and PSAE groups. In respect of brain energy system, significant degradations of the brain adenosine triphos- phate (ATP) (p < 0.05) were observed in the brainstems and even the whole brains of rats though PLAE treatments. Moreover, we found that the brain Adenosine monophosphate (AMP) were clearly decreased (p < 0.05) in rat cerebrum and brainstem regions, while the brain Adenosine revealed an increasing propensity (p = 0.076) in the cerebrums of freely behaving rats. After experiment-2 (n = 15), the γ-aminobutyric acid (GABA) concentrations were statistically (p < 0.05) enhanced and the ratios of Glutamate/GABA were simultaneously reduced (p < 0.05) in rat brainstems, no matter which one dose (100 or 500 mg/kg BW) of PLAE were used. Results indicated that PLAE could influence the target neurotransmitters that related to rat circadian rhythms in the specific brain regions, possessing the potentialities as a sedative or sleep-aid for hypnic therapy purposes.展开更多
Effects of rolled leaf gene Rl(t) on grain quality characters of hybrid rice were analyzed by using three pairs of rolled leaf near-isogenic lines under two fertilizer treatments. Under normal fertilizer level (e.g...Effects of rolled leaf gene Rl(t) on grain quality characters of hybrid rice were analyzed by using three pairs of rolled leaf near-isogenic lines under two fertilizer treatments. Under normal fertilizer level (e.g. 450 kg urea per ha), head rice rates and milled rice recovery of rolled leaf hybrids were significantly higher than those of corresponding non-rolled crosses, while the chalky rice rate and chalkiness were all lower. Of the RVA profiles, the peak viscosity, the hot paste viscosity and the breakdown viscosity of the rolled were all higher than those of the corresponding non-rolled ones to various degrees. Increasing fertilizer application for promoting panicle development increased the brown, milled and head rice rates except for Shanyou 63, furthermore, significant difference of head rice rates existed between the rolled leaf Shanyou 559 and Shanyou 559; while the peak viscosity, the hot paste viscosity and the breakdown viscosity all decreased to different levels; changes of values of other characters had no apparent regularity. It suggested that Rl(t) could improve rice quality under certain conditions.展开更多
An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck (L.) Benth. On germination and growth behavior of some popular agricultural crops (receptor) of Bangl...An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck (L.) Benth. On germination and growth behavior of some popular agricultural crops (receptor) of Bangladesh. Experiments were set on sterilized petridishes with a photoperiod of 24 h at room temperature of 27-30℃. The effects of the different concentrations of aqueous extracts were compared to distil water (control.). The aqueous extracts of leaf caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor plants. Bioassays indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration (50%-100%) had the stronger inhibitory effect whereas the lower concentration (10%-25%) showed stimulatory effect in some cases. The study also revealed that, inhibitory effect was much pronounced in root and lateral root development rather than germination and shoot growth.展开更多
BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve function...BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve functions of central adrenergic nerve; moreover, 5-serotonergic nerve and the combination with choline can produce synergistic effect and enhance learning and memory ability so as to improve learning and memory disorder of patients with Alzheimer disease (AD). OBJECTIVE : To observe the effects of GSL combining with choline on learning and memory of AD model rats DESIGN : Randomized grouping design and controlled animal study SETIING : Department of Pharmacology, Taishan Medical College MATERIALS : The experiment was carried out in the Pharmacological Department of Medical College of Jilin University from October 1996 to January 1997. Forty healthy male Wistar rats of clean grade were randomly divided into 5 groups, including sham-injury group, model group, GSL group, choline group and combination group, with 8 rats in each group. Main medications: GSL with the volume more than 92.8% was provided by Department of Chemistry, Norman Bethune Medical College of Jilin University. Panaxatriol, the main component, was detected with thin layer scanning technique and regarded as the index of GSL quality [(55±1)%, CV= 2%, n = 5]. Choline was provided by the Third Shanghai Laboratory Factory. METHODS : 150 nmol quinolinic acid was used to damage bilateral Meynert basal nuclei of adult rats so as to establish AD models. Rats in GSL, choline and combination groups were intragastric administrated with 400 mg/kg GSL, 200 mg/kg choline (20 mL/kg), and both respectively last for 17 days starting from two days before operation. Rats in sham-injury group and model group were perfused with the same volume of distilled water once in each morning for the same days. (1) Passive avoidance step-down test: Five minutes later, rats jumped up safe platform when they were shocked with 36 V alternating current. If rats jumped down from the platform and the feet touched railings, the response was wrong. Numbers of wrong response were recorded within 3 minutes, and then the test was redone after 24 hours. (2) Morris water-maze spatial localization task: Swimming from jumping-off to platform directly was regarded as right response. Additionally, 4 successively right responses were regarded as the standard. Each rat was trained 10 times a day with 120 s per time for 3 successive days. The interval was 30 s. Three days later, numbers of right response were recorded. The training times were increased to 30 for unlearned rats. (3) Measurement of activity of choline acetylase in cerebral cortex: Rats were sacrificed at 17 days after operation to obtain cerebral cortex to measure activity of choline acetylase with radiochemistry technique. (4) Synergistic effect: It was expressed as Q value: Q value = factual incorporative effect/anticipant incorporative effect; Q ≥ 1 was regarded as synergistic effect. Anticipant incorporative effect = (EA+EB-EA·EB), EA and EB were single timing effect, respectively in GSL group and choline group. E(step-down test and Morris water maze test) = (x in model group - factual value in medicine groups)/x in model group; E (activity of choline acetylase) = (factual value in medicine groups -xin model group)/xin model group. MAIN OUTCOME MEASURES : (1) Passive avoidance step-down test and Morris water-maze spatial localization task in the study of learning and memory; (2) activity of choline acetylase. RESULTS : All 40 rats were involved in the final analysis. (1) Passive avoidance response: At learning phase on first day and retesting phase on the next day, numbers of wrong responses within 3 minutes were more in model group than sham operation group, and there was significant difference [(5.88±1.46), (2.25±0.87) times; (2.63±1.06), (0.50±0.53) times; P 〈 0.01]; numbers of wrong responses within 3 minutes were less in combination group than model group, and there was significant difference [learning phase: (1.12±0.83), (5.88±1.46) times; retesting phase: (0.38±0.74), (2.63±1.06)times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and 1.59, respectively and it showed synergistic effect. Spatial localization task: Training times were more in model group than sham operation group, and there was significant difference [(2.9±2.5), (12.6±3.5) times; P 〈 0.01]. Training times were less in combination group than model group, and there was significant difference [(11.8±2.4), (27.9±2.5) times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and it showed synergistic effect. (3) Activity of choline acetylase: Activity was lower in model group than sham operation group, and there was significant difference [(30.56±8.33), (61.11 ±8.33) nkat/g; P 〈 0.01]. Activity was higher in combination group than model group and there was significant difference [(50.00±8.33), (30.56±8.33) nkat/g, P 〈 0.01];moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.5 and it showed synergistic effect. CONCLUSZON: GSL in combination with choline can synergically improve the disorder of learning and memory of AD model rats. Its mechanism may be involved in enhancing the function of central cholinergic system.展开更多
Group testing is a method that can be used to estimate the prevalence of rare infectious diseases,which can effectively save time and reduce costs compared to the method of random sampling.However,previous literature ...Group testing is a method that can be used to estimate the prevalence of rare infectious diseases,which can effectively save time and reduce costs compared to the method of random sampling.However,previous literature only demonstrated the optimality of group testing strategy while estimating prevalence under some strong assumptions.This article weakens the assumption of misclassification rate in the previous literature,considers the misclassification rate of the infected samples as a differentiable function of the pool size,and explores some optimal properties of group testing for estimating prevalence in the presence of differential misclassification conforming to this assumption.This article theoretically demonstrates that the group testing strategy performs better than the sample by sample procedure in estimating disease prevalence when the total number of sample pools is given or the size of the test population is determined.Numerical simulation experiments were conducted to evaluate the performance of group tests in estimating prevalence in the presence of dilution effect.展开更多
A thermo-sensitive white stripe-leaf mutant (tws) was selected from the M2 progeny of a japonica variety, Jiahua 1, treated by ^60 Co γ-radiation. In comparison with the wild type parent, the mutant displayed a phe...A thermo-sensitive white stripe-leaf mutant (tws) was selected from the M2 progeny of a japonica variety, Jiahua 1, treated by ^60 Co γ-radiation. In comparison with the wild type parent, the mutant displayed a phenotype of white stripe on the 3rd and 4th leaves, but began to turn normal green on the 5th leaf when grown at low temperatures (20℃ and 24℃). Furthermore, the content of total chlorophyll showed an obvious decrease in the leaves with white stripe. These results suggest that the expression of the mutant trait was thermo-sensitive and correlated with the leaf age of seedlings. The genetic analysis indicated that the mutant trait was controlled by a single recessive nuclear gene, designated as tws. In addition, by using SSR markers and an F2 segregating population derived from the cross between the tws mutant and 9311, tws was mapped between the markers MM3907 and MM3928 with a physical distance of 86 kb on dce chromosome 4.展开更多
基金the grant from National Key Research and Development Program of China(Grant No.2021YFE0110000)the grant from Tianjin Municipal Science and Technology Foundation(Grant No.22JCYBJC00160).
文摘Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain unclear.Methods:The effective components of green tea,mulberry leaf and corn silk were extracted and enriched.Mixture design of experiments was used to study the influences of different combinations on the cell viability and glucose uptake level of L6 myoblasts,so as to determine the optimal synergistic hypoglycemic combination.The possible hypoglycemic mechanism of the optimal synergistic combination was explored by cytotoxicity assay,glucose uptake assay,and western blot.Results:Three polyphenol enrichment fractions of the herbs,30%ethanol elution fraction of green tea(GT),50%ethanol elution fraction of mulberry leaf(ML)and 60%ethanol elution fraction of corn silk(CS)were obtained.The antioxidant activities of GT-30%,ML-50%and CS-60%were superior to those of crude extracts,and showed strong potential inα-amylase andα-glucosidase inhibition activities.The optimal synergistic combination of crude extracts G7(crude extract of green tea:crude extract of mulberry leaf:crude extract of corn silk=1:5:3),polyphenol enrichment fractions R3(GT-30%:ML-50%:CS-60%=1:7:1)and monomers X2(epigallocatechin gallate:morusin:formononetin=3:1:2)were selected,respectively.G7,R3,and X2 showed promoting effects on the cell viability and glucose uptake of L6 myoblasts within the detected concentration range.In addition,G7,R3,and X2 could increase the expression levels of p-PI3K/PI3K and p-Akt/Akt in L6 myoblasts,and promote the translocation of Glut4,but G7 and R3 showed more significant effects.Conclusion:The synergistic hypoglycemic effects of green tea,mulberry leaf and corn silk had the characteristics of multiple-components and multiple-targets with p-PI3K/PI3K,p-Akt/Akt and the translocation of Glut4 signal pathways involved.The three traditional herbs might have the potential to be combined used for the prevention and treatment of diabetes based on the synergistic hypoglycemic effects.
基金supported by the Doctor Foundation of Gansu Academy of Agricultural Sciences,China(2020GAAS33)the Young Science and Technology Lifting Engineering Talents in Gansu Province,China(2020-18)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2017-ICS)。
文摘Maize(Zea mays L.) is an economically vital grain crop that is cultivated worldwide. In 2011, a maize foliar disease was detected in Lingtai and Lintao counties in Gansu Province, China. The characteristic signs and symptoms of this disease include irregular chlorotic lesions on the tips and edges of infected leaves and black punctate fruiting bodies in dead leaf tissues. Given favourable environmental conditions, this disease spread to areas surrounding Gansu. In this study, infected leaves were collected from Gansu and Ningxia Hui Autonomous Region between 2018and 2020 to identify the disease-causing pathogen. Based on morphological features, pathogenicity tests, and multilocus phylogenetic analysis involving internal transcribed spacer(ITS), 18S small subunit rDNA(SSU), 28S large subunit rDNA(LSU), translation elongation factor 1-alpha(TEF), and β-tubulin(TUB) sequences, Eutiarosporella dactylidis was identified as the causative pathogen of this newly discovered leaf blight. Furthermore, an in vitro bioassay was conducted on representative strains using six fungicides, and both fludioxonil and carbendazim were found to significantly inhibit the mycelial growth of E. dactylidis. The results of this study provide a reference for the detection and management of Eutiarosporella leaf blight.
基金This work was supported by the Joint Fund of NSFC for Enterprise Innovation and Development(Grant No.U19B6003-02-06)the National Natural Science Foundation of China(Grant No.51974331)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20200525)The authors would like to sincerely acknowledge these funding programs for their financial support.Particularly,the support provided by the China Scholarship Council(CSC)during a visit of Ke Sun(File No.202106440065)to the University of Alberta is also sincerely acknowledged.
文摘To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(i.e.altered stress conditions)for the fractured core models and the vuggy core models have similar change patterns.The ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy reservoirs.Since each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and 1.Meanwhile,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was proposed.It is proved theoretically that the ESCP of CFVR generally varies between 0 and 1.Additionally,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial model.The concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the weakest.In general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs.
文摘The study on the changes of stomatal sensitivity in relation to xylem ABA during periodical soil drying and the effect of leaf water status on the stomatal sensitivity has confirmed that xylem ABA concentration is a good indicator of soil water status around roots and the relation between xylem ABA concentration and predawn leaf water potential remained constant during the three consecutive soil drying cycles based on the slopes of the fitted lines. The sensitivity of stomata to xylem ABA increased substantially as the soil drying cycles progressed, and the xylem ABA concentration needed to cause a 50% decrease of stomatal conductance was as low as 550 nmol/L in the next two soil drying cycle, as compared with the 750 nmol/L ABA in the first cycle of soil drying. The results using the split_root system showed that leaf water deficit significantly enhanced the stomatal response to xylem ABA and the xylem ABA concentration needed to cause a 50% decrease in stomatal conductance was 2 to 4 times smaller in the whole_root_drying treatment than those in the semi_root_drying treatment. These results suggested that the sensitivity of stomata to xylem ABA concentration is not a fixed characteristic.
基金Supported by Sichuan Industry Technology Innovation Strategic Alliance(2010Z00024)~~
文摘[Objective] Considering invasion of Eupatorium adenophorum, a growth in-hibitor of the plant was developed based on plant sensitivity, to make evaluation on control effects and to determine the optimal concentration. [Method] According to field test method, the effects of treatments with growth inhibitor at 0.5%, 1%, 1.5%and 2% on Eupatorium adenophorum were explored and the growth of other weeds was observed to research selectivity of plant inhibitor on the plant. [Result] The growth inhibitor had significant effects on ground parts of Eupatorium adenophorum. Specifical y, after 2 h, Eupatorium adenophorum was damaged seriously and the damage degree went worse upon inhibitor concentration. After 5 d, the control effect of the inhibitorreached 41.5% with concentration at 1.5%, reached 90.2% with the concentration at 1%, and 100% with the concentration at 1.5% and 2%. After 15 d, the control effect achieved 64.6%, 91.7%, 98.9% and 100% with concentrations at 0.5%, 1%, 1.5% and 2%. Stil , the effects of growth inhibitors on root system were limited. For example, new branches would grow from base part if the inhibitor con-centration is too low. On the other hand, the growth inhibitor is of sensitivity and selectivity, which would not hurt other plants. [Conclusion] It is feasible to rapidly control growth and development and even kil Eupatorium adenophorum based on plant sensitivity and it is proved that the growth inhibitor at 1.5% would considerably restrict and kil Eupatorium adenophorum. Therefore, the concentration of growth in-hibitors should be over 1.5%.
基金Supported by Agricultural Science and Technology Stride Plan(2009-16)Natural Science Fund in Hainan(808202)Scienceand Technology Project from Chinese Academy of Tropical Agricultural Sciences(Rky09)~~
文摘Soil structure and nutrient ingredient before and after shattering and returning sugarcane leaf as well as its technologies and methods were comparatively analyzed in this study to discuss the main reasons primarily,while the controlling technologies were proposed by combining cultivation,management and technical measures.
基金Intercooperation,Agroforestry Improvement Project and Village and Farm Forestry Project (IC-VFFP, AFIP) Rajshahi (Funded by Swiss Agency for Development Cooperation,SDC)
文摘Allelopathic effects of different doses of Eucalyptus camaldulensis leaf litters were investigated through an experiment in the green house of Institute of Forestry and Environmental Sciences, Chittagong, Bangladesh. Three popular agricultural crops: Falen (Vigna unguiculata), Chickpea (Cicer arietinum), Arhor (Cajanus cajan) and two widely used plantation trees: Sada koroi (Albizia procera) and Ipil ipil (Leucaena leucocephala) were selected as bioassay species. Experiment was set on tray at room temperature 27℃. The effects of different doses of leaf litter extracts were compared to the control. Results suggest that leaf litters of E, camaldulesis induced inhibitory effects, It was also found that the effect depend on concentration of extract and litterfall, type of receiver species. Higher concentration of the materials had the higher effect and vice versa. Though all the bioassay species were suppressed some of them showed better performance. Vigna unguiculata, Cicer arietinum are recommended in agroforestry based on this present Experiment output. In mixed plantation, Leucaena leucochephala is a better choice while compared to Albizia procera.
基金Project(AA17202007) supported by the Special Funding for Innovation-Driven Development of Guangxi Province,China。
文摘The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and differential scanning calorimetry(DSC).The water-cooled and aged alloy exhibits higher strength than the air-cooled and aged alloy;2.5%pre-stretching of tensile deformation exerts little effect on strength of water-cooled and aged alloy but increases that of air-cooled and aged one,and therefore the yield strength reduction rate due to slow quenching decreases from about 3.8%to about 1.0%,reducing quench sensitive effect.For the air-cooled alloy,pre-stretching increases the sizes ofη'strengthening precipitates but also increases their quantity and the ratio of diameter to thickness,resulting in enhanced strengthening and higher strength after aging.The reason has been discussed based on microstructure examination by TEM and DSC.
基金National Natural Science Foundation of China(No.41401002)Jilin Province Science Foundation for Youths(No.20160520077JH)
文摘Spectral index methodology has been widely used in Leaf Area Index(LAI) retrieval at different spatial scales. There are differences in the spectral response of different remote sensors and thus spectral scale effect generated during the use of spectral indices to retrieve LAI. In this study, PROSPECT, leaf optical properties model and Scattering by Arbitrarily Inclined Layers(SAIL) model, were used to simulate canopy spectral reflectance with a bandwidth of 5 nm and a Gaussian spectral response function was employed to simulate the spectral data at six bandwidths ranging from 10 to 35 nm. Additionally, for bandwidths from 5 to 35 nm, the correlation between the spectral index and LAI, and the sensitivities of the spectral index to changes in LAI and bandwidth were analyzed. Finally, the reflectance data at six bandwidths ranging from 40 to 65 nm were used to verify the spectral scale effect generated during the use of the spectral index to retrieve LAI. Results indicate that Vegetation Index of the Universal Pattern Decomposition(VIUPD) had the highest accuracy during LAI retrieval. Followed by Normalized Difference Vegetation Index(NDVI), Modified Simple Ratio Indices(MSRI) and Triangle Vegetation Index(TVI), although the coefficient of determination R^2 was higher than 0.96, the retrieved LAI values were less than the actual value and thus lacked validity. Other spectral indices were significantly affected by the spectral scale effect with poor retrieval results. In this study, VIUPD, which exhibited a relatively good correlation and sensitivity to LAI, was less affected by the spectral scale effect and had a relatively good retrieval capability. This conclusion supports a purported feature independent of the sensor of this model and also confirms the great potential of VIUPD for retrieval of physicochemical parameters of vegetation using multi-source remote sensing data.
基金This study was supported by the National Natural Science Foundation of China(U22B2075,52274056,51974356).
文摘A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation.
基金Under the auspices of National Natural Science Foundation of China(No.41071033,41101049)China Postdoctoral Science Foundation(No.2012M511361)
文摘Microorganisms are nutritious resources for various soil fauna.Although soil fauna grazing affects microorganism composition and decomposition rate,the responses of soil fauna and leaf litter decomposition to added microorganism is little understood.In this study,in the coniferous and broad-leaved mixed forest of Tahe County in the northern Da Hinggan Mountains,China,three sampling sites(each has an area of 10 m2) were selected.The first two sites were sprinkled with 250 times(EM1) and 1000 times(EM2) diluted effective microorganism(EM) preparations evenly,and the third site was sprinkled with the same volume of water as a control site.The responses of soil fauna structure and leaf litter decomposition to EM treatment were conducted during three years.The results revealed that EM treatment resulted in significant increase of soil organic matter.The number of soil fauna in the EM1 and EM2 sites increased by 12.88% and 2.23% compared to the control site,and among them springtails and mites showed the highest increase.However,the groups of soil fauna in the EM1 and EM2 sites decreased by 6 and 9,respectively.And the changes in the diversity and evenness index were relatively complicated.EM treatment slowed the decomposition of broad-leaved litter,but accelerated the decomposition of coniferous litter.However,the decomposition rate of broad-leaved litter was still higher than that of coniferous litter.The results of this study suggested that the added microorganisms could help individual growth of soil fauna,and this method led to a change in the process of leaf litter decomposition.This paper did not analyze the activity of soil microorganisms,thus it is difficult to clearly explain the complex relationships among litter type,soil fauna and soil microorganisms.Further research on this subject is needed.
基金jointly supported by the National Natural Science Foundation of China(42361024,42101030,42261079,and 41961058)the Talent Project of Science and Technology in Inner Mongolia of China(NJYT22027 and NJYT23019)the Fundamental Research Funds for the Inner Mongolia Normal University,China(2022JBBJ014 and 2022JBQN093)。
文摘Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.
基金supported by grants from the National Natural Science Foundation of China(32272083)the National Key Research and Development Program of China(2016YFD0100102).
文摘Agropyron cristatum(2n=4x=28,PPPP)is a wild relative of common wheat which contains a large number of desirable genes that can be exploited for wheat improvement.Wheat–A.cristatum 2P alien translocation lines exhibit many desirable traits,such as small flag leaves,a high spikelet number and density,and a compact plant type.An agronomic trait evaluation and a genetic analysis were carried out on translocation lines and backcross populations of these lines carrying different translocation fragments.The results showed that a translocation fragment from 2PT-3(2PL)reduced the length of the flag leaves,while translocation fragments from 2PT-3(2PL)and 2PT-5(2PL(0.60–1.00))reduced the width of the flag leaves.A translocation fragment from 2PT-13(2PS(0.18–0.36))increased the length and area of the flag leaves.Translocation fragments from 2PT-3(2PL)and 2PT-8(2PL(0.86–1.00))increased the density of spikelets.Translocation fragments from 2PT-7(2PL(0.00–0.09)),2PT-8(2PL(0.86–1.00)),2PT-10(2PS),and 2PT-13(2PS(0.18–0.36))reduced plant height.This study provides a scientific basis for the effective utilization of wheat–A.cristatum translocation lines.
文摘An experiment was conducted to assess the effect of leaf litter of Leucaena leucocephala on two forest crops Sada koroi (Albizia procera), Ipil ipil (L. leucocephala) and three agricultural crops Falen (Vigna unguiculata), Chickpea (Citer arietinum) and Arhor (Cajanus cajan) in the nursery of the Institute of Forestry and Environmental Sciences, Chittagong University, Bangladesh, in a Randomized Block Design. Results suggested that leaf litters ofL. leucocephala induced inhibitory effects on germination and growth of bioassay. It was also found that the effect depended on concentration of extract and litterfall, type of receptor species. Higher concentration of the materials had the higher effect and vice versa. Growth response of receptor crops varied with the variation of leaf litter application. The study revealed that application of low-dose leaf litter specially litter of 10 g·m^-2 had stimulating effect on shoot growth of C. arietinum, Vunguiculata and A. procera. While in all other cases significant inhibitory effect was observed and it was significantly increased with the increase of leaf litter application. However, the trend of inhibition was uneven with treatments. Root growth was found to be more affected than shoot growth.
文摘Peanut (Arachis hypogaea L.) leaf aqueous extracts (PLAE) has been reputed to be a type of sleep-aid in China. To investigate the sedative effects and effect pathways of PLAE, rats (n = 31) were employed in two experiments and intragastrically administrated of (1) distilled water, PLAE (500 mg/kg body weight (BW)) and peanut stem aqueous extracts (PSAE, 500 mg/kg BW);(2) 0, 100 or 500 mg/kg BW of PLAE, respectively for at least 14 days. Six relevant neurotransmitters were measured finally. Experiment-1 (n = 16) results showed that the brain Lactate were significantly elevated (p < 0.05) in rat cerebrums after PLAE administrations, compared with Control and PSAE groups. In respect of brain energy system, significant degradations of the brain adenosine triphos- phate (ATP) (p < 0.05) were observed in the brainstems and even the whole brains of rats though PLAE treatments. Moreover, we found that the brain Adenosine monophosphate (AMP) were clearly decreased (p < 0.05) in rat cerebrum and brainstem regions, while the brain Adenosine revealed an increasing propensity (p = 0.076) in the cerebrums of freely behaving rats. After experiment-2 (n = 15), the γ-aminobutyric acid (GABA) concentrations were statistically (p < 0.05) enhanced and the ratios of Glutamate/GABA were simultaneously reduced (p < 0.05) in rat brainstems, no matter which one dose (100 or 500 mg/kg BW) of PLAE were used. Results indicated that PLAE could influence the target neurotransmitters that related to rat circadian rhythms in the specific brain regions, possessing the potentialities as a sedative or sleep-aid for hypnic therapy purposes.
文摘Effects of rolled leaf gene Rl(t) on grain quality characters of hybrid rice were analyzed by using three pairs of rolled leaf near-isogenic lines under two fertilizer treatments. Under normal fertilizer level (e.g. 450 kg urea per ha), head rice rates and milled rice recovery of rolled leaf hybrids were significantly higher than those of corresponding non-rolled crosses, while the chalky rice rate and chalkiness were all lower. Of the RVA profiles, the peak viscosity, the hot paste viscosity and the breakdown viscosity of the rolled were all higher than those of the corresponding non-rolled ones to various degrees. Increasing fertilizer application for promoting panicle development increased the brown, milled and head rice rates except for Shanyou 63, furthermore, significant difference of head rice rates existed between the rolled leaf Shanyou 559 and Shanyou 559; while the peak viscosity, the hot paste viscosity and the breakdown viscosity all decreased to different levels; changes of values of other characters had no apparent regularity. It suggested that Rl(t) could improve rice quality under certain conditions.
文摘An experiment was conducted to observe the inhibitory effects of the leaf extracts derived from Albizia lebbeck (L.) Benth. On germination and growth behavior of some popular agricultural crops (receptor) of Bangladesh. Experiments were set on sterilized petridishes with a photoperiod of 24 h at room temperature of 27-30℃. The effects of the different concentrations of aqueous extracts were compared to distil water (control.). The aqueous extracts of leaf caused significant inhibitory effect on germination, root and shoot elongation and development of lateral roots of receptor plants. Bioassays indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration (50%-100%) had the stronger inhibitory effect whereas the lower concentration (10%-25%) showed stimulatory effect in some cases. The study also revealed that, inhibitory effect was much pronounced in root and lateral root development rather than germination and shoot growth.
文摘BACKGROUND: Central adrenergic nerve and 5-serotonergic nerve can influence central cholinergic nerve on learning and memory and make easy for study; however, ginsenoside of stem and leaf (GSL) can improve functions of central adrenergic nerve; moreover, 5-serotonergic nerve and the combination with choline can produce synergistic effect and enhance learning and memory ability so as to improve learning and memory disorder of patients with Alzheimer disease (AD). OBJECTIVE : To observe the effects of GSL combining with choline on learning and memory of AD model rats DESIGN : Randomized grouping design and controlled animal study SETIING : Department of Pharmacology, Taishan Medical College MATERIALS : The experiment was carried out in the Pharmacological Department of Medical College of Jilin University from October 1996 to January 1997. Forty healthy male Wistar rats of clean grade were randomly divided into 5 groups, including sham-injury group, model group, GSL group, choline group and combination group, with 8 rats in each group. Main medications: GSL with the volume more than 92.8% was provided by Department of Chemistry, Norman Bethune Medical College of Jilin University. Panaxatriol, the main component, was detected with thin layer scanning technique and regarded as the index of GSL quality [(55±1)%, CV= 2%, n = 5]. Choline was provided by the Third Shanghai Laboratory Factory. METHODS : 150 nmol quinolinic acid was used to damage bilateral Meynert basal nuclei of adult rats so as to establish AD models. Rats in GSL, choline and combination groups were intragastric administrated with 400 mg/kg GSL, 200 mg/kg choline (20 mL/kg), and both respectively last for 17 days starting from two days before operation. Rats in sham-injury group and model group were perfused with the same volume of distilled water once in each morning for the same days. (1) Passive avoidance step-down test: Five minutes later, rats jumped up safe platform when they were shocked with 36 V alternating current. If rats jumped down from the platform and the feet touched railings, the response was wrong. Numbers of wrong response were recorded within 3 minutes, and then the test was redone after 24 hours. (2) Morris water-maze spatial localization task: Swimming from jumping-off to platform directly was regarded as right response. Additionally, 4 successively right responses were regarded as the standard. Each rat was trained 10 times a day with 120 s per time for 3 successive days. The interval was 30 s. Three days later, numbers of right response were recorded. The training times were increased to 30 for unlearned rats. (3) Measurement of activity of choline acetylase in cerebral cortex: Rats were sacrificed at 17 days after operation to obtain cerebral cortex to measure activity of choline acetylase with radiochemistry technique. (4) Synergistic effect: It was expressed as Q value: Q value = factual incorporative effect/anticipant incorporative effect; Q ≥ 1 was regarded as synergistic effect. Anticipant incorporative effect = (EA+EB-EA·EB), EA and EB were single timing effect, respectively in GSL group and choline group. E(step-down test and Morris water maze test) = (x in model group - factual value in medicine groups)/x in model group; E (activity of choline acetylase) = (factual value in medicine groups -xin model group)/xin model group. MAIN OUTCOME MEASURES : (1) Passive avoidance step-down test and Morris water-maze spatial localization task in the study of learning and memory; (2) activity of choline acetylase. RESULTS : All 40 rats were involved in the final analysis. (1) Passive avoidance response: At learning phase on first day and retesting phase on the next day, numbers of wrong responses within 3 minutes were more in model group than sham operation group, and there was significant difference [(5.88±1.46), (2.25±0.87) times; (2.63±1.06), (0.50±0.53) times; P 〈 0.01]; numbers of wrong responses within 3 minutes were less in combination group than model group, and there was significant difference [learning phase: (1.12±0.83), (5.88±1.46) times; retesting phase: (0.38±0.74), (2.63±1.06)times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and 1.59, respectively and it showed synergistic effect. Spatial localization task: Training times were more in model group than sham operation group, and there was significant difference [(2.9±2.5), (12.6±3.5) times; P 〈 0.01]. Training times were less in combination group than model group, and there was significant difference [(11.8±2.4), (27.9±2.5) times, P 〈 0.01]; moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.07 and it showed synergistic effect. (3) Activity of choline acetylase: Activity was lower in model group than sham operation group, and there was significant difference [(30.56±8.33), (61.11 ±8.33) nkat/g; P 〈 0.01]. Activity was higher in combination group than model group and there was significant difference [(50.00±8.33), (30.56±8.33) nkat/g, P 〈 0.01];moreover, effect was stronger than that in GSL group and choline group. The Q value was 1.5 and it showed synergistic effect. CONCLUSZON: GSL in combination with choline can synergically improve the disorder of learning and memory of AD model rats. Its mechanism may be involved in enhancing the function of central cholinergic system.
基金supported by the National Natural Science Foundation of China(Grant No.72091212).
文摘Group testing is a method that can be used to estimate the prevalence of rare infectious diseases,which can effectively save time and reduce costs compared to the method of random sampling.However,previous literature only demonstrated the optimality of group testing strategy while estimating prevalence under some strong assumptions.This article weakens the assumption of misclassification rate in the previous literature,considers the misclassification rate of the infected samples as a differentiable function of the pool size,and explores some optimal properties of group testing for estimating prevalence in the presence of differential misclassification conforming to this assumption.This article theoretically demonstrates that the group testing strategy performs better than the sample by sample procedure in estimating disease prevalence when the total number of sample pools is given or the size of the test population is determined.Numerical simulation experiments were conducted to evaluate the performance of group tests in estimating prevalence in the presence of dilution effect.
基金supported by the National Natural Science Foundation of China(Grant No.30971552)Shanghai Municipal Education Commission of China(Grant No.09YZ167)+1 种基金Shanghai Municipal Science and Technology Commission of China(Grant Nos.08PJ14085,9391912300 and 09DJ1400505)the Leading Academic Discipline Project of Shanghai Municipal Education Commission,China(Grant No.J50401)
文摘A thermo-sensitive white stripe-leaf mutant (tws) was selected from the M2 progeny of a japonica variety, Jiahua 1, treated by ^60 Co γ-radiation. In comparison with the wild type parent, the mutant displayed a phenotype of white stripe on the 3rd and 4th leaves, but began to turn normal green on the 5th leaf when grown at low temperatures (20℃ and 24℃). Furthermore, the content of total chlorophyll showed an obvious decrease in the leaves with white stripe. These results suggest that the expression of the mutant trait was thermo-sensitive and correlated with the leaf age of seedlings. The genetic analysis indicated that the mutant trait was controlled by a single recessive nuclear gene, designated as tws. In addition, by using SSR markers and an F2 segregating population derived from the cross between the tws mutant and 9311, tws was mapped between the markers MM3907 and MM3928 with a physical distance of 86 kb on dce chromosome 4.