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A New Caffeoylquiniclactone, Neochlorgeniclatone from the Leaves of Betula platyphylla Suk. 被引量:2
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作者 Su Juan WANG Yue Hu PEI Hui Ming HUA 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期509-510,共2页
A new caffeoylquiniclactone, named neochlorgeniclatone, was isolated from the leaves of Betula platyphylla Suk. The Structure was established by spectroscopic data.
关键词 Neochlorgeniclatone Betula platyphylla Suk. leaveS
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Effects of Incorporating Mango (Mangifera indica), Avocado (Persea americana) and Guava (Psidium guajava) Leaves Powder in the Ration on Growth Characteristics in Rabbits
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作者 Emma Fortune Magloire Bend Hervé Tchoffo +2 位作者 Margaret Mary Momo Chongsi Meli Ivan Pavel Kouti Ferdinand Ngoula 《Food and Nutrition Sciences》 CAS 2024年第10期991-1003,共13页
A study conducted on burgundy rabbits evaluated the effects of rations containing mango (Mangifera indica), avocado (Persea americana) and guava (Psidium guajava) powder. For this purpose, 36 rabbits (20 males and 16 ... A study conducted on burgundy rabbits evaluated the effects of rations containing mango (Mangifera indica), avocado (Persea americana) and guava (Psidium guajava) powder. For this purpose, 36 rabbits (20 males and 16 females) aged 60 to 70 days with an average weight of 1012 ± 133 g were divided randomly into 4 equal groups (T0, T1, T2 and T3) of 9 animals each according to body weight (bw). The rabbits were divided throughout the trial, the animals were fed, those of group T0 (control) with a standard feed without any type of leaf powder, while those of groups 1, 2 and 3 received the standard feed supplemented with Mangifera indica, Persea americana and Psidium guajava leaves powder at the rate of 0.5% respectively. After two months of treatment, the animals were fasted for 12 hours (20 h - 8 h) and sacrificed to evaluate carcass and digestive organ weights. The results revealed that the values of feed intake, live weight and weight gain were non-significantly (p > 0.05) increased in all animals regardless of the ration in reference to the control. The different leaves powder induced an increase in carcass yield in rabbits but this increase was only significant (p M. indica leaf powder (51.03 ± 0.24) as compared to the control (48.63 ± 0.74). Gut length was significantly increased in animals fed rations containing Psidium guajava and Persea americana leaves powder compared to the control. A significant increase in gut weight was observed in animals fed the Persea americana leaf supplemented ration. In general, mango leaf powder performed better than other types of powders. 展开更多
关键词 AVOCADO Growth Characteristics leaveS GUAVA MANGO Rabbit
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EAG and behavioral responses of Helicoverpa armigera males to volatiles from poplar leaves and their combinations with sex pheromone 被引量:15
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作者 邓建宇 黄永平 魏洪义 《Journal of Zhejiang University Science》 EI CSCD 2004年第12期1577-1582,共6页
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antenn... Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles shouldmodify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field. 展开更多
关键词 Helicoverpa armigera Wilted leave volatiles Chinese black poplar Sex pheromone EAG Wind-tunnel bioassay
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Processing Effects on Selected Antioxidant Activities and Metabolizing Enzyme Inhibition of M. Koneigii (Curry Leaves) Extracts
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作者 Karthik Medabalimi Rajwinder Kaur Martha Verghese 《Food and Nutrition Sciences》 CAS 2024年第6期470-483,共14页
Curry leaves, scientifically termed Murraya koenigii, are renowned in South Asian cuisine for their flavor enhancement and potential health benefits, including antioxidative, anti-inflammatory, and antidiabetic proper... Curry leaves, scientifically termed Murraya koenigii, are renowned in South Asian cuisine for their flavor enhancement and potential health benefits, including antioxidative, anti-inflammatory, and antidiabetic properties. This study aimed to evaluate the impact of thermal processing methods on curry leaves by analysing Total Phenolic Content (TPC), Total Flavonoid Content (TFC), antioxidant activity, and metabolizing enzyme inhibition. Fresh curry leaves were subjected to thermal treatments: Oven-dried at 60˚C and Air-dried at 25˚C for 2 weeks. Extracts were prepared using Ethanol and water solvents. Results indicated that Air-dried leaves exhibited significantly higher TPC (5132.65 mg GAE/100 g) and TFC (243.13 mg CE/100 g) compared to Fresh and Oven-dried leaves. Antioxidant assays show that oven-dried curry leaves at 60˚C displayed higher results in NORS, FRAP, and TEAC assays compared to Fresh and Air-dried leaves. Ethanol extracts showed better extraction of bioactive compounds than aqueous extracts. Moreover, Lipase inhibition activity was notably high, indicating potential health benefits. This study provides valuable insights into the effects of processing methods on curry leaf extracts, emphasizing the importance of solvent selection for optimal extraction of bioactive compounds. 展开更多
关键词 Murraya Koenigii Curry leaves ANTIOXIDANTS PHYTOCHEMICALS Metabolizing Enzymes
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Surface wildfire in conifer broad-leaved forests of the Hyrcanian region of Iran:short-term effect on regeneration and damage to trees 被引量:1
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作者 Seyed Abdolkhalegh Yadegarnejad Mehdi Dylam Jafarabad Najmeh Mohammadi Savadkoohi 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第2期425-434,共10页
Wildfires in recent years have resulted in degradation and damage to the Hyrcanian forest ecosystems in Northern Iran.This study was carried out to investigate fire damage to trees and changes in regeneration in early... Wildfires in recent years have resulted in degradation and damage to the Hyrcanian forest ecosystems in Northern Iran.This study was carried out to investigate fire damage to trees and changes in regeneration in early-season growth after wildfires in the Golestan Province.For this purpose,a random sampling plan was used,with 60 circular plots(each plot is 1000 m2) for each stand and 240 circular(25 m2) plots for regeneration within the burned and unburned areas,respectively.In each plot,habitat factors were recorded,including crown canopy percentage,forest stratum,herb-layer cover percentage,species,diameter at breast height,tree and regeneration quality,and quantity of seedlings and saplings.Our results showed that bark is an important factor for fire resistance in Hyrcanian forests.The Persian ironwood and European yew has the highest and lowest fire resistance;as broad leave species are more resistant than needle leaf species.Density of regeneration in unburned area was higher than burned area,and statistical analysis showed significant differences for all species between two areas.Fire effects on sapling were different among species which indicates sapling has different resistance to fire.Forest floor fuel,season,stand composition and microclimate have more effects on fire severity while environmental factors,regeneration and management practices shaping future composition stands. 展开更多
关键词 Broad leave European yew Seedling and sapling WILDfire
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Judgment of Aroma Types of Middle and Upper Flue-cured Tobacco Leaves Based on Proportions of Aroma Components 被引量:3
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作者 詹军 周芳芳 +5 位作者 包崇彦 毛春堂 邓国宾 王伟 杨俊 张晓龙 《Agricultural Science & Technology》 CAS 2013年第4期612-619,共8页
[Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples (63 C3F and 65 B2F) f... [Objective] This study aimed to establish mathematical models for judging the aroma types of flue-cured tobacco leaves from the upper and middle parts of plants. [Method] A total of 128 samples (63 C3F and 65 B2F) from 11 main tobac- co production provinces of China were selected as materials. Stepwise discriminant analysis was applied to samples with different aroma types and discriminant function was expressed with the proportions of 67 aroma components in total aroma con- stituents as the index. [Result] The ratio of most aroma components in clear and full aroma tobacco leaves was higher than that in middle aroma leaves. The ratios of 51, 43 and 40 aroma components of clear, middle and full aroma tobaccos were higher in upper leaves than that in middle leaves. Aroma components dominated certain aroma types differed between middle and upper leaves. The proportions of 18 and 11 aroma components in upper and middle leaves were led in the stepwise discriminant function respectively. Self-validation and cross-validation methods were applied to evaluate the original samples, and the accuracy rates reached 100% and 98.6% on middle leaves, 96.37% and 94.4% on upper leaves. The accuracy rates on some other samples reached 100% on middle leaves and 91.7% on upper leaves predicted with the model. [Conclusion] The ratio of aroma components as discriminant index could improve discriminant accuracy significantly in the middle and upper leaves. It could be used to analyze aroma types objectively, accurately and quickly. 展开更多
关键词 Flue-cured tobacco Aroma components Middle leaves Upper leaves Ratio Aroma types Discriminant analysis
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Effects of Carrot (Daucus carota) Leaves Powder on Reproductive and Growth Characteristics of Rabbit (Oryctolagus cuniculus) Does
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作者 Margaret Mary Momo Chongsi Nienga Sorelle Deutcheu +6 位作者 Marie Noel Bertine Noumbissi Emma Fortune Magloire Bend Hervé Tchoffo Kelvin Nguatem Bertin Narcisse Vemo Tahir Markhous Adam Mahamat Ferdinand Ngoula 《Open Journal of Animal Sciences》 2024年第4期302-320,共19页
The present study was conducted to evaluate the effects of carrot leaf powder in the diet on reproductive and growth characteristics in rabbits. Thirty sexually matured rabbits does of 8 months old, 3.00 to 3.20 kg, w... The present study was conducted to evaluate the effects of carrot leaf powder in the diet on reproductive and growth characteristics in rabbits. Thirty sexually matured rabbits does of 8 months old, 3.00 to 3.20 kg, were divided into three groups of 10 rabbits each, which were comparable in terms of body weight. Throughout the experiment, the rabbits of group 1 (control group) were fed ad libitum with a feed not containing carrot leaf powder (control ration), while those of groups 2 and 3 received the control ration supplemented with carrot leaf powder in concentrations of 0.5% and 1% respectively. Data was collected on feed intake, weight gain, receptivity, fertility, gestation length of does, litter size, weight, viability and sex ratio of the young rabbits till 5 weeks post-partum. There was no significant (P > 0.05) difference in the fertility rate, gestation duration and sex ratio of the kits with reference to the control. Litter size at birth was not significantly (P > 0.05) influenced in does fed diets containing carrot leaf powder compared to the control. However, the reversed effects were observed at five weeks post-partum. The live weight of weaned kits and weight gain of rabbit does at birth were significantly (P < 0.05) increased in treated rabbits compared to the control. The supplementation of carrot leaf powder in feed can improve production performance in female rabbits, through their antioxidant activities thanks to their various components, thus fighting against oxidative stress effects to which animals are exposed both from endogenous and environmental sources. 展开更多
关键词 Antioxidant Carrot leaves Growth Rabbit Doe REPRODUCTION
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Chemical Components of Achyranthes bidentata Leaves by Ultra High Performance Liquid Chromatography-Mass Spectrometry 被引量:1
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作者 Haiyang DONG Jinshuo MA Fulin YAN 《Medicinal Plant》 CAS 2019年第4期16-19,共4页
[Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical c... [Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical components of A. bidentata leaves were rapidly analyzed using the ultra high performance liquid chromatography-time of flight-high resolution mass spectrometry (UHPLC-TOF-MS).[Results] Thirty eight chemical compounds were identified in samples of A. bidentata leaves collected from Wen County of Henan Province, in which seven chemical compounds had the relative content higher than 5%, linoleic acid reached 25.7% and inokosterone A reached 13.8%.[Conclusions] A. bidentata leaves contain many kinds of chemical compounds. This study is expected to provide a certain basis for further extraction of linoleic acid and inokosterone A. 展开更多
关键词 Achyranthes bidentata leaveS ULTRA high performance liquid chromatography-mass SPECTROMETRY (UHPLC-MS) Chemical components Inokosterone
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Synthesis of reduced graphene oxide nanosheets from sugarcane dry leaves by two-stage pyrolysis for antibacterial activity
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作者 Baskar Thangaraj Pravin Raj Solomon +4 位作者 Nutthapon Wongyao Mohamed I.Helal Ali Abdullah Sufian Abedrabbo Jamal Hassan 《Nano Materials Science》 EI CAS CSCD 2024年第5期625-634,共10页
Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is mad... Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is made on the dry leaves of sugarcane(Saccharum officinarum)as an alternative raw material so as to be economical and environmentally benign.The dry leaves are subjected to two-step pyrolysis without any catalyst or reducing agent in far divergent temperatures to produce as prepared and acid treated rGOs.They were evaluated by UV–Vis.,FTIR,XRD,Raman spectroscopy,TGA/DTG,BET,FESEM-EDS and TEM.The as prepared rGO has few layers with irregular and folded architecture whereas acid-treated rGO has thinly stacked crumpled sheets with many wrinkles on its surface.The prepared rGOs have multilayered graphitic structure due to the unique ratio between G and D bands.Acid treated rGO has poor thermal stability as compared to that of as-prepared rGO at high temperatures due to the variation in the oxygen-containing functional groups.Acid treated rGO has low antibacterial activity as compared to that of the as-prepared rGO due to the paucity of the functional groups. 展开更多
关键词 Biomass wastes Sugarcane dry leaves PYROLYSIS Reduced graphene oxide Antibacterial activity
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Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America
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作者 Zhihui Wang Philip A.Townsend +1 位作者 Eric L.Kruger Anna K.Schweiger 《Forest Ecosystems》 SCIE CSCD 2024年第5期728-742,共15页
Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multi... Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental change.However,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade leaves.We presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North America.We investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait expression.Generally,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific characteristics.Covariation between sun and shade leaf traits,and trait-environment relationships were overall consistent across species.The main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural traits.Taxonomy and canopy position collectively explained most of the foliar trait variation.This study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem functions.Our findings have implications for efficient field sampling,and trait mapping with remote sensing. 展开更多
关键词 Foliar traits Leaf trait variation Trait-environment covariation Shade leaves NEON Leaf spectroscopy
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An Improved YOLOv8-Based Method for Real-Time Detection of Harmful Tea Leaves in Complex Backgrounds
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作者 Xin Leng Jiakai Chen +2 位作者 Jianping Huang Lei Zhang Zongxuan Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期2963-2981,共19页
Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and qu... Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and quality of tea leaves,leading to significant economic losses.While early and accurate identification coupled with the removal of infected leaves can mitigate widespread infection,manual leaves removal remains time-con-suming and expensive.Utilizing robots for pruning can significantly enhance efficiency and reduce costs.How-ever,the accuracy of object detection directly impacts the overall efficiency of pruning robots.In complex tea plantation environments,complex image backgrounds,the overlapping and occlusion of leaves,as well as small and densely harmful leaves can all introduce interference factors.Existing algorithms perform poorly in detecting small and densely packed targets.To address these challenges,this paper collected a dataset of 1108 images of harmful tea leaves and proposed the YOLO-DBD model.The model excels in efficiently identifying harmful tea leaves with various poses in complex backgrounds,providing crucial guidance for the posture and obstacle avoidance of a robotic arm during the pruning process.The improvements proposed in this study encompass the Cross Stage Partial with Deformable Convolutional Networks v2(C2f-DCN)module,Bi-Level Routing Atten-tion(BRA),Dynamic Head(DyHead),and Focal Complete Intersection over Union(Focal-CIoU)Loss function,enhancing the model’s feature extraction,computation allocation,and perception capabilities.Compared to the baseline model YOLOv8s,mean Average Precision at IoU 0.5(mAP0.5)increased by 6%,and Floating Point Operations Per second(FLOPs)decreased by 3.3 G. 展开更多
关键词 Harmful tea leaves YOLO-DBD Focal-CIoU Loss dynamic head Bi-Level Routing Attention
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The Protective Effects of Flavonoids from Scutellaria Baicalensis Georgi Stems and Leaves on Oligodendrocyte Damage Induced by Aβ1-42
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作者 Tangtang Song Yinhui Yao Yazhen Shang 《Pharmacology & Pharmacy》 2024年第1期1-13,共13页
Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. ... Aim: This study aimed to investigate the protective effects of flavonoids from the stem and leaves of Scutellaria baicalensis Georgi (SSFs) against Aβ<sub>1-42</sub>-induced oligodendrocytes (OL) damage. Methods: Immunofluorescence was used for the detection of myelin-associated glycoprotein (MAG), a characteristic protein of rat oligodendrocytes (OLN-93 cells). To evaluate the potential protective effects of SSFs on OLN-93 cells injured by Aβ<sub>1-42</sub>, an injury model was established by subjecting OLN-93 cells to Aβ<sub>1-42</sub> exposed. Cell morphology was examined using an inverted microscope, while cell viability was assessed using the colorimetric method of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Additionally, lactate dehydrogenase (LDH) was measured using the pyruvic acid reduction assay. The Ginkgo biloba leaf extract (GBE) injection was used as a positive control. Results: A total of >95% of the MAG immunofluorescence-positive cells were identified as oligodendrocytes. Gradually increasing concentrations of SSFs impaired the cells, and the maximum nondetrimental dose for OLN-93 cells was 75 mg/L. This study assessed the effects of SSFs on OLN-93 cells damaged by Aβ<sub>1-42</sub>. The results indicated that SSFs significantly improved OLN-93 cell morphological abnormal changes, increased the OLN-93 cell survival rate, and reduced LDH release. Conclusion: SSFs can alleviate Aβ<sub>1-42</sub>-induced damage of OL. 展开更多
关键词 Flavonoids form the Stem and leaves of Scutellaria baicalensis Georgi 1-42 OLIGODENDROCYTES DAMAGE
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Physicochemical Characterisation of Flours from Local Cereals and Powder from Cassava (Manihot esculenta Crantz) Leaves Varieties Cultivated in the Northern-Cameroon in Order to Supplement Infant Flours
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作者 Mathieu Barbi Charles Touwang +2 位作者 Emmanuel Panyoo Akdowa Augustin Goudoum Armand Abdou Bouba 《Open Journal of Applied Sciences》 2024年第8期2009-2026,共18页
The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. I... The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. In this paper, a A survey to identify the cereals used in the preparation of infant porridge in the Northern Cameroon was done by using 447 mothers having children between 06 and 59 months from areas (Gbakoungue, Sassa-Mbersi, Sanguere-Ngal and Kotkong-Wouldata) with high rate on malnourished children. Flour was prepared from the most preponderant cereals and Cassava leaves powder from varieties identified by the Regional Centre of Agricultural Research (CRRA) of Wakwa and local population. Flour and powder samples obtained were subjected to chemical composition analysis. Parameters analysed were crude proteins, total carbohydrates, ash, total fats, total phenols, total tannins, total carotenoids, vitamin C or cyanide. Also Iron, calcium and zinc were determined. The results revealed that white maize (62%) was the main cereal used in the preparation of infant porridge followed respectively by red sorghum, white rice and muskwari. Ten cassava varieties were identified: three (03) by CRRA (TME, 96/1/14 and IRAD 4115) and seven (south, gambada, sweet, Benin, six months, M. glaziovii and grouna) by local population. Amongst cereals flour, those from white maize indicated high protein (10.09%), carbohydrates (84.46%) and total fat (7.46%) contents. The powder from 96/14/14 cassava variety showed high amount of iron (11.98 mg/100g), calcium (751.02 g/100g) and low cyanide content (1.21 ppm) amongst all the cassava leaves powder samples. The supplementation of white maize flour by cassava leaves powder from 96/14/14 variety could therefore be recommended for the preparation of infant flours. 展开更多
关键词 Infant Flour Cereals Flour Cassava leaves Powder Chemical Composition Northern Cameroon
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Efficient strategies for leave-one-out cross validation for genomic best linear unbiased prediction 被引量:3
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作者 Hao Cheng Dorian J.Garrick Rohan L.Fernando 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第3期733-737,共5页
Background: A random multiple-regression model that simultaneously fit all allele substitution effects for additive markers or haplotypes as uncorrelated random effects was proposed for Best Linear Unbiased Predictio... Background: A random multiple-regression model that simultaneously fit all allele substitution effects for additive markers or haplotypes as uncorrelated random effects was proposed for Best Linear Unbiased Prediction, using whole-genome data. Leave-one-out cross validation can be used to quantify the predictive ability of a statistical model.Methods: Naive application of Leave-one-out cross validation is computationally intensive because the training and validation analyses need to be repeated n times, once for each observation. Efficient Leave-one-out cross validation strategies are presented here, requiring little more effort than a single analysis.Results: Efficient Leave-one-out cross validation strategies is 786 times faster than the naive application for a simulated dataset with 1,000 observations and 10,000 markers and 99 times faster with 1,000 observations and 100 markers. These efficiencies relative to the naive approach using the same model will increase with increases in the number of observations.Conclusions: Efficient Leave-one-out cross validation strategies are presented here, requiring little more effort than a single analysis. 展开更多
关键词 leave-one-out cross validation GBLUP
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Intention to Leave and Associated Factors among Health Professionals in Jimma Zone Public Health Centers, Southwest Ethiopia
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作者 Taju Kalifa Shimeles Ololo Fikru Tafese 《Open Journal of Preventive Medicine》 2016年第1期31-41,共11页
Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little... Background: Inadequate human resources are a major constraint to improving global health. The health sector is characterized by a high turnover coupled with internal as well as external brain drain but there is little information on intention to leave among health professionals in public health centers of Jimma Zone, Oromia Regional State. The aim of this study is to assess intention to leave and associated factors among health professionals in public health centers of Jimma Zone, southwest Ethiopia. Methods: A cross-sectional quantitative and qualitative study was conducted on seven randomly selected woredas (districts) which have 53 public health centers. All health professionals in sampled district public health centers were included (n = 505). Factor analysis was employed for all Likert scale instruments to extract factor(s) representing each of the scales using SPSS version 16.0. The qualitative data was analyzed by thematic analysis methods. Ethical approval was obtained from Jimma University. Results: Four hundred fifty five (90.1%) health professionals participated in the study;out of this, 290 (63.7%) had intention to leave. Among variables, job satisfaction (Beta = -0.298, (95% CI, -0.568 to -0.029), working environment (Beta = -0.612, (95% CI, -0.955 to -0.270), and organizational management (Beta = -0.552, (95% CI, 0.289 to 0.815) had statistically significant association with intention to leave among health professionals in public health centers of Jimma Zone. Conclusions: The overall intention to leave among health professionals was high. Level of job satisfaction, working environment, work pressure, and organizational management had statistically significant association with intention to leave. Thus, responsible bodies should aggressively work on the concerns identified, like, improvements in salary, promotion in terms of training/educational opportunity, improving working environment, and transfer of health professionals, and improvement of the leadership skills of managers. 展开更多
关键词 Intention to leave Job Satisfaction Working Environment Work Pressure organizational Management Health Professionals Public Health Centers Jimma Zone
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Studies on the Characteristics of Chlorophyll Fluorescence of Winter Wheat Flag Leaves at Different Developing Stages 被引量:28
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作者 卢庆陶 李卫华 +4 位作者 蒋高明 戈巧英 郝乃斌 孙家柱 郭仁峻 《Acta Botanica Sinica》 CSCD 2001年第8期801-804,共4页
The parameters of fluorescence induction kinetics and the maximal light-saturated net CO2 assimilation rate (P-sat) of the flag leaves of four cultivars of winter wheat (Triticum aestivum L.) were compared at three di... The parameters of fluorescence induction kinetics and the maximal light-saturated net CO2 assimilation rate (P-sat) of the flag leaves of four cultivars of winter wheat (Triticum aestivum L.) were compared at three different developing stages for the first time. From the blooming stage to the milky stage, the quantum efficiency of PS II photochemistry (F-v/F-m) declined slightly only at the milk stage. The photochemical quenching co-efficient (qP), actual quantum yield of photosystem II (PS II)electron transport (Phi (PSII)) and P-sat decreased substantially (> 15%), while the non-photochemical quenching co-efficient (qN) increased significantly (> 100%). There existed a linear correlation between the Phi (PSII) and the P-sat (r = 0.918). The results indicate that with the senescence of the flag leaves of winter wheat the photosynthetic efficiency including that of the energy transport and the CO2 assimilation significantly decreased. 展开更多
关键词 winter wheat flag leave fluorescence kinetics PHOTOSYNTHESIS
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves Free radicals scavenging Total phenol Total flavones
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Hypoglycemic Effect of Forsythia suspensa Leaves on Diabetic Mice 被引量:9
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作者 刘静 杨建雄 《Agricultural Science & Technology》 CAS 2013年第1期98-99,175,共3页
[Objective] This study aimed to investigate the hypoglycemic effect of Forsythia suspensa leaves in diabetic mice. [Method] The model of hyperglycemia mice were obtained by injecting streptozotocin intraperitoneally t... [Objective] This study aimed to investigate the hypoglycemic effect of Forsythia suspensa leaves in diabetic mice. [Method] The model of hyperglycemia mice were obtained by injecting streptozotocin intraperitoneally to study the effect of F. suspensa leaves on lowering blood sugar of hyperglycemia mice and normal ani- mals. [Result] F. suspensa leaves could antagonize the streptozotocin-reducing mice hyperglycemia and significantly reduce the fasting blood glucose level of diabetic mice. [Coaclusion] F. suspensa leaves exhibits a good therapeutic effect on diabetic mice and has a good development prospect. 展开更多
关键词 Forsythia suspensa leaves Lower blood sugar DIABETES
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Study of the Short-time Eco-physiological Response of Plant Leaves to Dust 被引量:20
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作者 陈雄文 《Acta Botanica Sinica》 CSCD 2001年第10期1058-1064,共7页
The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the ... The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the eco-physiology of leaves of these species. After being covered by dust the instant net photosynthetic rates of most plant species changed insignificantly, but it decreased by more than 35% for 5 species, and it increased by-more than 57% for Ginkgo biloba L. The respiration rates of 12 plant species increased significantly, but it decreased significantly for Malus pumila Mill. (M. communis D C.) and Cotinus coggygria (L.) Scop., and it changed insignificantly for the other 8 species. The transpiration rates of 5 plant species increased significantly, however, they decreased for 9 species, and changed insignificantly for the other 8 species. Platanus occidentalis L. had highest dust carrying capacity. After 2 h the physiological indices did not change significantly for Diospyros kaki L. f., G. biloba and Populus tomentosa Carr. The implications of the research are that Ulmus laevis Pall., M. pumila (M. communis), D. kaki and G. biloba are suitable for amelioration of dust storm damage and increase in local economical development near the sources of dust storms in western China. And in the cities, such as Beijing and other dust areas, the plants have high dust-carrying capacity can be planted for air cleaning. 展开更多
关键词 leaveS eco-physiological response DUST
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves Non-target organisms Safety evaluation
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