55 research outputs found
Physiological impacts of early defoliation on the cold hardiness of grapevine (Vitis vinifera L.) 'Sultana'
Low winter temperatures are one of the limiting factors of grape production worldwide. This study was undertaken to inquire about the effects of postharvest early defoliation on the cold hardiness of grapevine. The grapevines samples, cv. Sultana, were defoliated at two stages (10 and 25 days after harvest), and then they were compared with natural leaf fall. Cane samples were collected in December 2017 and February 2018, and analyzed in terms of water content, soluble carbohydrate, and proline concentrations in both bud and cane tissues. The samples were then subjected to freezing treatments i. e. -8, -12, -15, -18, -21, and -24 °C for evaluating the levels of cold hardiness. Based on these results, early defoliation reduced proline and soluble carbohydrate concentrations but increased the water content compared to the control. Leaf removal also decreased abscisic acid concentration in the bud samples. Investigation of cold hardiness by electrolyte leakage and tetrazolium staining examinations showed that the defoliation decreased cold hardiness. Results demonstrated that leaf removal between the growing season and the beginning of the acclimation stage decreased the metabolite concentration in buds and canes and resulted to a reduction of cold hardiness
Gaussian mixture model-based contrast enhancement
In this study, a method for enhancing low-contrast images is proposed. This method, called Gaussian mixture model-based contrast enhancement (GMMCE), brings into play the Gaussian mixture modelling of histograms to model the content of the images. On the basis of the fact that each homogeneous area in natural images has a Gaussian-shaped histogram, it decomposes the narrow histogram of low-contrast images into a set of scaled and shifted Gaussians. The individual histograms are then stretched by increasing their variance parameters, and are diffused on the entire histogram by scattering their mean parameters, to build a broad version of the histogram. The number of Gaussians as well as their parameters are optimised to set up a Gaussian mixture modelling with lowest approximation error and highest similarity to the original histogram. Compared with the existing histogram-based methods, the experimental results show that the quality of GMMCE enhanced pictures are mostly consistent and outperform other benchmark methods. Additionally, the computational complexity analysis shows that GMMCE is a low-complexity method
Induced polyploidy and broad variation in phytochemical traits and altered gene expression in Salvia multicaulis
Induced polyploidy is nowadays an important strategy in plant breeding and for the development of new crops. Salvia multicaulis Vahl is a valuable medicinal plant that produce precious bioactive metabolites including triterpenic acids (TAs) and phenolic compounds. Hence, at first, for selecting elite lines, both HPLC and GC-MC analyses were performed on fourteen S. multicaulis lines. Then, seeds of selected lines of S. multicaulis were exposed to different concentrations (0.00, 0.05, 0.1, and 0.2 %) of colchicine for 24 or 48 h. The flow cytometric analysis and chromosome counting were used to confirm ploidy level of tetraploid control (2n = 4x = 28, 2C DNA = 1.36 pg) and hexaploid (2n = 6x = 42, 2C DNA = 1.97 pg) plants after seven-month. For the first time, the effects of in vitro polyploidization on morphological characteristics, TAs and phenolic acid contents as well as on the expression of six TAs biosynthesis related genes were investigated. The highest efficiency of hexaploidy (12.76 %) was achieved 48 h after exposure to 0.1 % colchicine concentration. The hexaploid plants showed different growth traits compared with those of tetraploid control plant; indeed, hexaploid plants had leaves with a darker green color, a lower trichome density, and lower plant height and root length. Moreover, there was a significant increase in rosmarinic acid and caffeic acid content in hexaploid plants compared with tetraploid control plants. Also, the increase of oleanolic acid (1.33 fold) content in hexaploids was associated with a significant increased expression of squalene synthase (SQS) and β-amyrin synthase (BAS) genes in hexaploid plants. Nevertheless, a significant decreased expression of squalene epoxidase (SQE), mixed-function amyrin synthase (MFAS), and lupeol synthase (LUS) was observed in hexaploid plants, that led to a reduced content of ursolic acid and betulinic acid compared with tetraploid control plants. These results confirmed that polyploidization is a breeding method with stochastic results in secondary metabolites production and gene expression related to biosynthetic pathways
Phenolics diversity among wild populations of Salvia multicaulis: as a precious source for antimicrobial and antioxidant applications
The genus Salvia L. belongs to the Lamiaceae family including several known species rich in natural compounds that are extensively used in pharmaceutical, food, and cosmetic industries. Salvia multicaulis populations contain a broad diversity of flavonoids and phenolic acids. The present study aimed to explore biological and pharmacological effects including antimicrobial and antioxidant activities of nineteen S. multicaulis populations (SMPs) grown in Iran for the first time. High content of rosmarinic acid (RA) in SMP12 (Gazan) (5.65 ± 0.33 mg/g DW) caused high antimicrobial activity against two bacteria (Staphylococcus aureus, Escherichia coli) and the fungus Candida albicans, while methanolic extract of SMP1 (Taleghan) showed high antioxidant activity due to high content of salvianolic acid A (SAA) and quercetin (0.53 ± 0.04 and 0.49 ± 0.12 mg/g DW, respectively). Altogether these results can be considered for further commercial exploitations to meet the demands of the food and pharmaceutical industries
Triterpenic and phenolic acids production changed in Salvia officinalis via in vitro and in vivo polyploidization: A consequence of altered genes expression
The induction of polyploidy is an efficient technique for creating a diversity of genetic, phenotypic, and phytochemical novelties in plant taxa. Sage (Salvia officinalis L.) is a well-known medicinal plant rich of valuable bioactive molecules such as triterpenic and phenolic acids. In the present study, the effect of in vitro and in vivo polyploidization on morphological characteristics, anatomical structures, phytochemical traits, and expression level of the genes involved in the biosynthesis of major triterpenic acids (ursolic, betulinic, and oleanolic acids) of the plant was studied. The sterile seeds treated with different concentrations (0, 0.05, 0.1, and 0.2%) of colchicine for 24 and 48 h were considered for polyploidy induction. Flow cytometry and chromosome counting were used to confirm the ploidy level of diploid (2n = 2x = 14, 2C DNA = 1.10 pg) and tetraploid (2n = 4x = 28, 2C DNA = 2.12 pg) plants after seven months. The highest polyploidy induction was obtained by applying 0.1% (w/v) colchicine for 48 h with an efficiency of 19.05% in vitro tetraploidy. Polyploids showed differences in leaf shape and color, leaf and stem thickness, trichrome density, root length, plant height, and number of leaves compared to diploid plants. There was also a significant decrease in rosmarinic acid content in polyploid (plants) as compared to diploid plants. Although a significant decrease in ursolic acid content was observed in polyploids, betulinic acid content associated with the expression levels of genes encoding enzymes being active in triterpene biosynthesis such as squalene epoxidase (SQE) and lupeol synthase (LUS). The expression of SQE and LUS was significantly increased in in vitro tertaploids (2.9-fold) and in vivo mixoploids (2.4-fold). The results confirm the idea that induced polyploidy can randomly alter breeding traits of plants as well as the content of bioactive compounds
Effect of pre- and post-harvest salicylic acid treatments on quality and antioxidant Properties of 'Red Delicious' apples during cold storage
Salicylic acid is a natural phenolic compound known as a plant hormone having positive effect on storage life and quality of fruits. This study aimed to investigate the effects of pre- and post-harvest application of salicylic acid on antioxidant properties and quality of ‘Red Delicious’ apples during 193 days cold (0±0.5°C) storage. Both pre- and post-harvest salicylic acid treatments did not affect soluble solid content, titratable acidity and fruit firmness, with the exception of 1 mM at pre-harvest application for titratable acidity. Fruit juice pH was reduced in all fruits at the end of storage, while it was not quite uniform during storage. Although there was no significant difference between the concentrations of salicylic acid in terms of fruit weight loss, but the highest amount of weight loss was observed in post-harvest treatments. Salicylic acid application increased total phenolics and antioxidant activity at the earlier stages of storage showing the highest capacity with 2 mM followed by 1 and 4 mM salicylic acid concentrations, while 1 mM concentration belonged to the highest antioxidant capacity at the end of storage. Anthocyanin content showed a gradual increase during storage until day 60, then decreased right afterwards. The highest amounts of anthocyanin were obtained from the concentrations of 1 and 2 mM salicylic acid in pre-harvest treatments, while 4 mM treatment was not encouraging. Overall, salicylic acid treatments could increase apple storage life and quality for a short period of time only
The study of aquaculture potential of Bojnord and Jajarm cities (Northern Khorasan province)
This study investigates the potential of Bojnord and Jarjam cities (Northern Khorasan province) for developments of Aquaculture. First of all, the current condition of Aquacture and fish farms were montiroed and recorde. Then, the information on geology, weather and climate as well as water resources data were gathered and evaluated. Climatology, geology and distribution of water reseources (i.e. reviers, springs, wells, and aqueducts) were prepared using GIS software. Evaluation of selected water resources in study area revealed suitability for culture of cold water fishes. Potentialities of the water resources for aquacture production were determined according to the latest guidline of Shilat organization. The maps of production potentialities were prepared for each water resources
Study of possibilities of aquaculture activities in the Gorgan Bay
The Gorgan golf is one of unique ecosystem in Iran which has plenty of known and unknown ecological values. Different agents threaten this ecosystem such as severe exploitation of natural resource on human behalf. This must be restricted using an accepted programs otherwise the ecological situation of the Gorgan golf will be worsen and finally to be died. In these study biological circumstances of the golf has been investigated in order to evaluate its ecological capacity to develop a sustainable aquaculture activities. This study started from Sep, 2010 and lasted to Oct, 2011. On the basis of the results from this study, and with considerations of all environmental conditions some aquatic organisms recommended for aquaculture purposes such as common carp (Cyprinus carpio), Caspian sea salmon (Salmo truta caspius), sturgeons stellate (Acipenser stellatus), Persian sturgeon (Acipenser persicus) and the great sturgeon (Huso huso). The farming procedure recommended as pen culture. In this study, the suitable surface of each pen, required information over each cultured species, suitable density and the amount of catch for each species have been determined. The amount of Nitrogen and Phosphorous originated from feeding and also secreted from fish species as the pollution index entered into the farming sites. The authorized amount of pollution factors for production and aquaculture in the Gorgan golf has been determined. In addition the study over the structure type for farming and also the suitable site for pen culture with consider to the facilities and conditions have been done. With notice to the above, with developing the aquaculture in this ecosystem, local workers will be run and plenty of capital will be invested and finally this will tend to the great revenues by producing of favor protein. This industry is able to change the region to a most important sites to produce aquatic organisms
Multifunctional Theranostic Graphene Oxide Nanoflakes as MR Imaging Agents with Enhanced Photothermal and Radiosensitizing Properties
The integration of multiple therapeutic and diagnostic functions into a single nanoplatform for image-guided cancer therapy has been an emerging trend in nanomedicine. We show here that multifunctional theranostic nanostructures consisting of superparamagnetic iron oxide (SPIO) and gold nanoparticles (AuNPs) scaffolded within graphene oxide nanoflakes (GO-SPIO-Au NFs) can be used for dual photo/radiotherapy by virtue of the near-infrared (NIR) absorbance of GO for photothermal therapy (PTT) and the Z element radiosensitization of AuNPs for enhanced radiation therapy (RT). At the same time, this nanoplatform can also be detected by magnetic resonance (MR) imaging because of the presence of SPIO NPs. Using a mouse carcinoma model, GO-SPIO-Au NF-mediated combined PTT/RT exhibited a 1.85-fold and 1.44-fold higher therapeutic efficacy compared to either NF-mediated PTT or RT alone, respectively, resulting in a complete eradication of tumors. As a sensitive multifunctional theranostic platform, GO-SPIO-Au NFs appear to be a promising nanomaterial for enhanced cancer imaging and therapy. © 2021 American Chemical Society
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Global investments in pandemic preparedness and COVID-19: development assistance and domestic spending on health between 1990 and 2026
Background
The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of national health systems, especially in low-income and middle-income countries (LMICs), as well as a robust global system for pandemic preparedness. We aimed to provide a comparative assessment of global health spending at the onset of the pandemic; characterise the amount of development assistance for pandemic preparedness and response disbursed in the first 2 years of the COVID-19 pandemic; and examine expectations for future health spending and put into context the expected need for investment in pandemic preparedness.
Methods
In this analysis of global health spending between 1990 and 2021, and prediction from 2021 to 2026, we estimated four sources of health spending: development assistance for health (DAH), government spending, out-of-pocket spending, and prepaid private spending across 204 countries and territories. We used the Organisation for Economic Co-operation and Development (OECD)'s Creditor Reporting System (CRS) and the WHO Global Health Expenditure Database (GHED) to estimate spending. We estimated development assistance for general health, COVID-19 response, and pandemic preparedness and response using a keyword search. Health spending estimates were combined with estimates of resources needed for pandemic prevention and preparedness to analyse future health spending patterns, relative to need.
Findings
In 2019, at the onset of the COVID-19 pandemic, US7·3 trillion (95% UI 7·2–7·4) in 2019; 293·7 times the 43·1 billion in development assistance was provided to maintain or improve health. The pandemic led to an unprecedented increase in development assistance targeted towards health; in 2020 and 2021, 37·8 billion was provided for the health-related COVID-19 response. Although the support for pandemic preparedness is 12·2% of the recommended target by the High-Level Independent Panel (HLIP), the support provided for the health-related COVID-19 response is 252·2% of the recommended target. Additionally, projected spending estimates suggest that between 2022 and 2026, governments in 17 (95% UI 11–21) of the 137 LMICs will observe an increase in national government health spending equivalent to an addition of 1% of GDP, as recommended by the HLIP.
Interpretation
There was an unprecedented scale-up in DAH in 2020 and 2021. We have a unique opportunity at this time to sustain funding for crucial global health functions, including pandemic preparedness. However, historical patterns of underfunding of pandemic preparedness suggest that deliberate effort must be made to ensure funding is maintained
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