World Academy of Science, Engineering and Technology
[Bioengineering and Life Sciences]
Online ISSN : 1307-6892
1407 Simulation of Red Blood Cells in Complex Micro-Tubes
Authors: Ting Ye, Nhan Phan-Thien, Chwee Teck Lim, Lina Peng, Huixin Shi
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In biofluid flow systems, often the flow problems of fluids of complex structures, such as the flow of red blood cells (RBCs) through complex capillary vessels, need to be considered. In this paper, we aim to apply a particle-based method, Smoothed Dissipative Particle Dynamics (SDPD), to simulate the motion and deformation of RBCs in complex micro-tubes. We first present the theoretical models, including SDPD model, RBC-fluid interaction model, RBC deformation model, RBC aggregation model, and boundary treatment model. After that, we show the verification and validation of these models, by comparing our numerical results with the theoretical, experimental and previously-published numerical results. Finally, we provide some simulation cases, such as the motion and deformation of RBCs in rectangular, cylinder, curved, bifurcated, and constricted micro-tubes, respectively.Keywords: aggregation, deformation, red blood cell, smoothed dissipative particle dynamics
Procedia PDF Downloads 1741406 Genetic Variability Studies of Some Quantitative Traits in Cowpea (Vigna unguiculata L. [Walp.] ) under Water Stress
Authors: Auwal Ibrahim Magashi, Lawan Dan Larai Fagwalawa, Muhammad Bello Ibrahim
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A research was conducted to study genetic variability of some quantitative traits in varieties of cowpea (Vigna unguiculata L. [Walp]) under water stressed from Zaria, Nigeria. Seeds of seven varieties of cowpea (Sampea 1, Sampea 2, IAR1074, Sampea 7, Sampea 8, Sampea 10 and Sampea 12) collected from Institute for Agricultural Research (IAR), Samaru, Zaria were screened for water stressed tolerance. The seeds were then sown in poly bags containing sandy-loam arranged in Completely Randomized Design with three replications for quantitative traits evaluation. The nutritional composition of the seeds obtained from the water stress tolerant varieties of cowpea were analyzed. The result obtained revealed highly significant difference (P ≤ 0.01) in the effects of water stress on the number of wilted and dead plants at 40 days after sowing (DAS) and significant (P ≤ 0.05) 34 DAS. However, sampea 10 has the highest mean performance in terms of number of wilted plants at 34 DAS while sampea 2 and IAR 1074 has the lowest mean performance. However, sampea 7 was found to have the highest mean performance for the number of wilted plants at 40 DAS and sampea 2 is lowest. The result for quantitative traits study indicated highly significant difference (P ≤ 0.01) in the plant height, number of days to 50% flowering, number of days to maturity, number of pods per plant, pod length, number of seeds per plant and 100 seed weight; and significant (P ≤ 0.05) at seedling height and number of branches per plant. Similarly, IAR1074 was found to have high performance in terms of most of the quantitative traits under study. However, sampea 8 has the highest mean performance at nutritional level. It was therefore concluded that, all the seven cowpea genotypes were water stress tolerant and produced considerable yield that contained significant nutrients. It was recommended that IAR1074 should be grown for yield while sampea 8 should be grown for protein supplements.Keywords: cowpea, genetic variability, quantitative traits, water stress
Procedia PDF Downloads 1571405 Experimental and Numerical Analysis of Wood Pellet Breakage during Pneumatic Transport
Authors: Julian Jaegers, Siegmar Wirtz, Viktor Scherer
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Wood pellets belong to the most established trade formats of wood-based fuels. Especially, because of the transportability and the storage properties, but also due to low moisture content, high energy density, and the homogeneous particle size and shape, wood pellets are well suited for power generation in power plants and for the use in automated domestic firing systems. Before they are thermally converted, wood pellets pass various transport and storage procedures. There they undergo different mechanical impacts, which leads to pellet breakage and abrasion and to an increase in fines. The fines lead to operational problems during storage, charging, and discharging of pellets, they can increase the risk of dust explosions and can lead to pollutant emissions during combustion. In the current work, the dependence of the formation of fines caused by breakage during pneumatic transport is analyzed experimentally and numerically. The focus lies on the influence of conveying velocity, pellet loading, pipe diameter, and the shape of pipe components like bends or couplings. A test rig has been built, which allows the experimental evaluation of the pneumatic transport varying the above-mentioned parameters. Two high-speed cameras are installed for the quantitative optical access to the particle-particle and particle-wall contacts. The particle size distribution of the bulk before and after a transport process is measured as well as the amount of fines produced. The experiments will be compared with results of corresponding DEM/CFD simulations to provide information on contact frequencies and forces. The contribution proposed will present experimental results and report on the status of the DEM/CFD simulations. The final goal of the project is to provide a better insight into pellet breakage during pneumatic transport and to develop guidelines ensuring a more gentle transport.Keywords: DEM/CFD-simulation of pneumatic conveying, mechanical impact on wood pellets during transportation, pellet breakage, pneumatic transport of wood pellets
Procedia PDF Downloads 1501404 Driving Forces of Net Carbon Emissions in a Tropical Dry Forest, Oaxaca, México
Authors: Rogelio Omar Corona-Núñez, Alma Mendoza-Ponce
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The Tropical Dry Forest not only is one of the most important tropical ecosystems in terms of area, but also it is one of the most degraded ecosystems. However, little is known about the degradation impacts on carbon stocks, therefore in carbon emissions. There are different studies which explain its deforestation dynamics, but there is still a lack of understanding of how they correlate to carbon losses. Recently different authors have built current biomass maps for the tropics and Mexico. However, it is not clear how well they predict at the local scale, and how they can be used to estimate carbon emissions. This study quantifies the forest net carbon losses by comparing the potential carbon stocks and the different current biomass maps in the Southern Pacific coast in Oaxaca, Mexico. The results show important differences in the current biomass estimates with not a clear agreement. However, by the aggregation of the information, it is possible to infer the general patterns of biomass distribution and it can identify the driving forces of the carbon emissions. This study estimated that currently ~44% of the potential carbon stock estimated for the region is still present. A total of 6,764 GgC has been emitted due to deforestation and degradation of the forest at a rate of above ground biomass loss of 66.4 Mg ha-1. Which, ~62% of the total carbon emissions can be regarded as being due to forest degradation. Most of carbon losses were identified in places suitable for agriculture, close to rural areas and to roads while the lowest losses were accounted in places with high water stress and within the boundaries of the National Protected Area. Moreover, places not suitable for agriculture, but close to the coast showed carbon losses as a result of urban settlements.Keywords: above ground biomass, deforestation, degradation, driving forces, tropical deciduous forest
Procedia PDF Downloads 1841403 Development of R³ UV Exposure for the UV Dose-Insensitive and Cost-Effective Fabrication of Biodegradable Polymer Microneedles
Authors: Sungmin Park, Gyungmok Nam, Seungpyo Woo, Young Choi, Sangheon Park, Sang-Hee Yoon
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Puncturing human skin with microneedles is critically important for microneedle-mediate drug delivery. Despite of extensive efforts in the past decades, the scale-up fabrication of sharp-tipped and high-aspect-ratio microneedles, especially made of biodegradable polymers, is still a long way off. Here, we present a UV dose insensitive and cost-effective microfabrication method for the biodegradable polymer microneedles with sharp tips and long lengths which can pierce human skin with low insertion force. The biodegradable polymer microneedles are fabricated with the polymer solution casting where a poly(lactic-co-glycolic acid) (PLGA, 50:50) solution is coated onto a SU-8 mold prepared with a reverse, ramped, and rotational (R3) UV exposure. The R3 UV exposure is modified from the multidirectional UV exposure both to suppress UV reflection from the bottom surface without anti-reflection layers and to optimize solvent concentration in the SU-8 photoresist, therefore achieving robust (i.e., highly insensitive to UV dose) and cost-effective fabrication of biodegradable polymer microneedles. An optical model for describing the spatial distribution of UV irradiation dose of the R3 UV exposure is also developed to theoretically predict the microneedle geometry fabricated with the R3 UV exposure and also to demonstrate the insensitiveness of microneedle geometry to UV dose. In the experimental characterization, the microneedles fabricated with the R3 UV exposure are compared with those fabricated with a conventional method (i.e., multidirectional UV exposure). The R3 UV exposure-based microfabrication reduces the end-tip radius by a factor of 5.8 and the deviation from ideal aspect ratio by 74.8%, compared with conventional method-based microfabrication. The PLGA microneedles fabricated with the R3 UV exposure pierce full-thickness porcine skins successfully and are demonstrated to completely dissolve in PBS (phosphate-buffered saline). The findings of this study will lead to an explosive growth of the microneedle-mediated drug delivery market.Keywords: R³ UV exposure, optical model, UV dose, reflection, solvent concentration, biodegradable polymer microneedle
Procedia PDF Downloads 1671402 Genome-Wide Assessment of Putative Superoxide Dismutases in Unicellular and Filamentous Cyanobacteria
Authors: Shivam Yadav, Neelam Atri
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Cyanobacteria are photoautotrophic prokaryotes able to grow in diverse ecological habitats, originated 2.5 - 3.5 billion years ago and brought oxygenic photosynthesis. Since then superoxide dismutases (SODs) acquired great significance due to their ability to catalyze detoxification of byproducts of oxygenic photosynthesis, i.e. superoxide radicals. Sequence information from several cyanobacterial genomes offers a unique opportunity to conduct a comprehensive comparative analysis of the superoxide dismutases family. In the present study, we extracted information regarding SODs from species of sequenced cyanobacteria and investigated their diversity, conservation, domain structure, and evolution. 144 putative SOD homologues were identified. SODs are present in all cyanobacterial species reflecting their significant role in survival. However, their distribution varies, fewer in unicellular marine strains whereas abundant in filamentous nitrogen-fixing cyanobacteria. Motifs and invariant amino acids typical in eukaryotic SODs were conserved well in these proteins. These SODs were classified into three major families according to their domain structures. Interestingly, they lack additional domains as found in proteins of other family. Phylogenetic relationships correspond well with phylogenies based on 16S rRNA and clustering occurs on the basis of structural characteristics such as domain organization. Similar conserved motifs and amino acids indicate that cyanobacterial SODs make use of a similar catalytic mechanism as eukaryotic SODs. Gene gain-and-loss is insignificant during SOD evolution as evidenced by absence of additional domain. This study has not only examined an overall background of sequence-structure-function interactions for the SOD gene family but also revealed variation among SOD distribution based on ecophysiological and morphological characters.Keywords: comparative genomics, cyanobacteria, phylogeny, superoxide dismutases
Procedia PDF Downloads 1331401 Comparative Analysis of Photosynthetic and Antioxidative Responses of Two Species of Anabaena under Ni and As(III) Stress
Authors: Shivam Yadav, Neelam Atri
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Cyanobacteria, the photosynthetic prokaryotes are indispensable components of paddy soil contribute substantially to the nitrogen economy however often appended with metal load. They are well known to play crucial roles in maintenance of soil fertility and rice productivity. Nickel is one such metal that plays a vital role in the cellular physiology, however at higher concentrations it exerts adverse effects. Arsenic is another toxic metalloid that negatively affects the cyanobacterial proliferation. However species-specific comparative responses under As and Ni is largely unknown. The present study focuses on the comparative effects of nickel (Ni2+) and arsenite (As(III)) on two diazotrophic cyanobacterial species (Anabaena doliolum and Anabaena sp. PCC7120) in terms of antioxidative aspects. Oxidative damage measured in terms of lipid peroxidation and peroxide content was significantly higher after As(III) than Ni treatment as compared to control. Similarly, all the studied enzymatic and non-enzymatic parameters of antioxidative defense system except glutathione reductase (GR) showed greater induction against As(III) than Ni. Moreover, integrating comparative analysis of all studied parameters also demonstrated interspecies variation in terms of stress adaptive strategies reflected through higher sensitivity of Anabaena doliolum over Anabaena PCC7120.Keywords: antioxidative system, arsenic, cyanobacteria, nickel
Procedia PDF Downloads 1541400 Production, Optimization, Characterization, and Kinetics of a Partially Purified Laccase from Pleurotus citrinopileatus and Its Application in Swift Bioremediation of Azo Dyes
Authors: Ankita Kushwaha, M. P. Singh
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Background: In the present investigation the efficiency of laccase (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) from Pleurotus citrinopileatus was assessed for the decolorization of azo dyes. Aim: Enzyme production, characterization and kinetics of a partially purified laccase from Pleurotus citrinopileatus were determined for its application in bioremediation of azo dyes. Methods & Results: Laccase has been partially purified by using 80% ammonium sulphate solution. Total activity, total protein, specific activity and purification fold for partially purified laccase were found to be 40.38U, 293.33mg/100ml, 0.91U/mg and 2.84, respectively. The pH and temperature optima of laccase were 5.0 and 50ºC, respectively, while the enzyme was most stable at pH 4.0 and temperature 30ºC when exposed for one hour. The Km of the partially purified laccase for substrates guaiacol, DMP (2,6-dimethoxyphenol) and syringaldazine (3,5-dimethoxy-4-hydroxybenzaldehyde azine) were 60, 95 and 26, respectively. This laccase has been tested for the use in the bioremediation of azo dyes in the absence of mediator molecules. Two dyes namely congo red and bromophenol blue were tested. Discussion: It was observed that laccase enzyme was very effective in the decolorization of these two dyes. More than 80% decolorization was observed within half an hour even in the absence of mediator and their lower Km value indicates that efficiency of the enzyme is very high. The results were promising due to quicker decolorization in the absence of mediators showing that it can be used as a valuable biocatalyst for quick bioremediation of azo dyes. Conclusion: The enzymatic properties of laccase from P. citrinopileatus should be considered for a potential environmental (biodegradation and bioremediation) or industrial applications.Keywords: azo dyes, decolorization, laccase, P.citrinopileatus
Procedia PDF Downloads 2211399 Predicting Dose Level and Length of Time for Radiation Exposure Using Gene Expression
Authors: Chao Sima, Shanaz Ghandhi, Sally A. Amundson, Michael L. Bittner, David J. Brenner
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In a large-scale radiologic emergency, potentially affected population need to be triaged efficiently using various biomarkers where personal dosimeters are not likely worn by the individuals. It has long been established that radiation injury can be estimated effectively using panels of genetic biomarkers. Furthermore, the rate of radiation, in addition to dose of radiation, plays a major role in determining biological responses. Therefore, a better and more accurate triage involves estimating both the dose level of the exposure and the length of time of that exposure. To that end, a large in vivo study was carried out on mice with internal emitter caesium-137 (¹³⁷Cs). Four different injection doses of ¹³⁷Cs were used: 157.5 μCi, 191 μCi, 214.5μCi, and 259 μCi. Cohorts of 6~7 mice from the control arm and each of the dose levels were sacrificed, and blood was collected 2, 3, 5, 7 and 14 days after injection for microarray RNA gene expression analysis. Using a generalized linear model with penalized maximum likelihood, a panel of 244 genes was established and both the doses of injection and the number of days after injection were accurately predicted for all 155 subjects using this panel. This has proven that microarray gene expression can be used effectively in radiation biodosimetry in predicting both the dose levels and the length of exposure time, which provides a more holistic view on radiation exposure and helps improving radiation damage assessment and treatment.Keywords: caesium-137, gene expression microarray, multivariate responses prediction, radiation biodosimetry
Procedia PDF Downloads 1981398 National Strategy for Swedish Wildlife Management
Authors: Maria Hornell, Marcus Ohman
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Nature, and the society it is a part of, is under constant change. The landscape, climate and game populations vary over time, as well as society's priorities and the way it uses the land where wildlife may proliferate. Sweden currently has historically large wildlife populations which are a resource for the benefit and joy of many people. Wildlife may also be seen as a problem as it may cause damage in contradiction to other human interests. The Swedish Environmental Protection Agency introduces a new long-term strategy for national wildlife management. The strategy envisions a wildlife management in balance. It focuses on wildlife values in a broad sense including outdoor recreation and tourism as well as conservation of biodiversity. It is fundamental that these values should be open and accessible for the major part of the population. For that to be possible new ways to manage, mitigate and prevent damages and other problems that wildlife causes need to be developed. The strategy describes a roadmap for the development and strengthening of Sweden's wildlife management until 2020. It aims at being applicable for those authorities and stakeholders with interest in wildlife management being a guide for their own strategies, goals, and activities.Keywords: wildlife management, strategy, Sweden, SEPA
Procedia PDF Downloads 2171397 The Genetic Diversity and Conservation Status of Natural Populus Nigra Populations in Turkey
Authors: Asiye Ciftci, Zeki Kaya
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Populus nigra is one of the most economically and ecologically important forest trees in Turkey, well known for its rapid growth, good ability to vegetative propagation and the extreme uses of its wood. Due to overexploitation, loss of natural distribution area and extreme hybridization and introgression, Populus nigra is one of the most threatened tree species in Turkey and Europe. Using 20 nuclear microsatellite loci, the genetic structure of European black poplar populations along the two largest rivers of Turkey was analyzed. All tested loci were highly polymorphic, displaying 5 to 15 alleles per locus. Observed heterozygosity (overall Ho = 0.79) has been higher than the expected (overall He = 0.58) in each population. Low level of genetic differentiation among populations (FST= 0,03) and excess of heterozygotes for each river were found. Human-mediated dispersal, phenotypic selection, high level of gene flow and extensive circulations of clonal materials may cause those situations. The genetic data obtained from this study could provide the basis for efficient in situ and ex-situ conservation and restoration of species natural populations in its natural habitat as well as having sustainable breeding and poplar plantations in the future.Keywords: populus, clonal, loci, ex situ
Procedia PDF Downloads 2951396 Embryonic and Larval Development of Pelophylax bedriagae (Amphibia, Anura), in Iran
Authors: Alireza Pesarakloo, Masoumeh Najibzadeh
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We studied the development and morphology of different larval stages of Pelophylax bedriagae at two rearing temperatures (20 and 24°C). Eggs collected from a breeding site in south-western Iran. Diagnostic morphological characters are provided for Gosner (1960) larval stages 1-46. The larvae hatched about seven days after egg deposition. Principal diagnostic feature including the formation of the funnel-shaped oral disc became discernible about ten days after hatch at Gosner stage 21 and degenerated at Gosner stage 42. Larvae developed faster at higher temperatures. The largest body length of larval P. bedriagae measured about 54mm in 70 days after egg deposition. Based on our results, the longest metamorphosis time was observed on temperature (20°C) whilst the shortest metamorphosis time occurred on temperature (24°C). Compared with the majority of other Palearctic Anurans, it appears that embryonic and larval development is usually slow rapid in P. bedriagae.Keywords: development, larval stages, Pelophylax bedriagae, temperatures
Procedia PDF Downloads 1761395 Superparamagnetic Sensor with Lateral Flow Immunoassays as Platforms for Biomarker Quantification
Authors: M. Salvador, J. C. Martinez-Garcia, A. Moyano, M. C. Blanco-Lopez, M. Rivas
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Biosensors play a crucial role in the detection of molecules nowadays due to their advantages of user-friendliness, high selectivity, the analysis in real time and in-situ applications. Among them, Lateral Flow Immunoassays (LFIAs) are presented among technologies for point-of-care bioassays with outstanding characteristics such as affordability, portability and low-cost. They have been widely used for the detection of a vast range of biomarkers, which do not only include proteins but also nucleic acids and even whole cells. Although the LFIA has traditionally been a positive/negative test, tremendous efforts are being done to add to the method the quantifying capability based on the combination of suitable labels and a proper sensor. One of the most successful approaches involves the use of magnetic sensors for detection of magnetic labels. Bringing together the required characteristics mentioned before, our research group has developed a biosensor to detect biomolecules. Superparamagnetic nanoparticles (SPNPs) together with LFIAs play the fundamental roles. SPMNPs are detected by their interaction with a high-frequency current flowing on a printed micro track. By means of the instant and proportional variation of the impedance of this track provoked by the presence of the SPNPs, quantitative and rapid measurement of the number of particles can be obtained. This way of detection requires no external magnetic field application, which reduces the device complexity. On the other hand, the major limitations of LFIAs are that they are only qualitative or semiquantitative when traditional gold or latex nanoparticles are used as color labels. Moreover, the necessity of always-constant ambient conditions to get reproducible results, the exclusive detection of the nanoparticles on the surface of the membrane, and the short durability of the signal are drawbacks that can be advantageously overcome with the design of magnetically labeled LFIAs. The approach followed was to coat the SPIONs with a specific monoclonal antibody which targets the protein under consideration by chemical bonds. Then, a sandwich-type immunoassay was prepared by printing onto the nitrocellulose membrane strip a second antibody against a different epitope of the protein (test line) and an IgG antibody (control line). When the sample flows along the strip, the SPION-labeled proteins are immobilized at the test line, which provides magnetic signal as described before. Preliminary results using this practical combination for the detection and quantification of the Prostatic-Specific Antigen (PSA) shows the validity and consistency of the technique in the clinical range, where a PSA level of 4.0 ng/mL is the established upper normal limit. Moreover, a LOD of 0.25 ng/mL was calculated with a confident level of 3 according to the IUPAC Gold Book definition. Its versatility has also been proved with the detection of other biomolecules such as troponin I (cardiac injury biomarker) or histamine.Keywords: biosensor, lateral flow immunoassays, point-of-care devices, superparamagnetic nanoparticles
Procedia PDF Downloads 2321394 Study on Developmental and Pathogenesis Related Genes Expression Deregulation in Brassica compestris Infected with 16Sr-IX Associated Phytoplasma
Authors: Samina Jam Nazeer Ahmad, Samia Yasin, Ijaz Ahmad, Muhammad Tahir, Jam Nazeer Ahmad
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Phytoplasmas are phloem-inhibited plant pathogenic bacteria that are transferred by insect vectors. Among biotic factors, Phytoplasma infection induces abnormality influencing the physiology as well as morphology of plants. In 16Sr-IX group phytoplasma-infected brassica compestris, flower abnormalities have been associated with changes in the expression of floral development genes. To determine whether methylation was involved in down-regulation of flower development, the process of DNA methylation and Demethylation was investigated as a possible mechanism for regulation of floral gene expression in phytoplasma infected Brassica transmitted by Orosious orientalis vector by using RT-PCR, MSRE-PCR, Southern blotting, Bisulfite Sequencing, etc. Transcriptional expression of methylated genes was found to be globally down-regulated in plants infected with phytoplasma, but not severely in those infested by insect vectors and variation in expression was found in genes involved in methylation. These results also showed that genes particularly orthologous to Arabidopsis APETALA3 involved in petal formation and flower development was down-regulated severely in phytoplasma-infected brassica and with the fact that phytoplasma and insect induce variation in developmental gene expression. The DNA methylation status of flower developmental gene in phytoplasma infected plants with 5-azacytidine restored gene expression strongly suggesting that DNA methylation was involved in down-regulation of floral development genes in phytoplasma infected brassica.Keywords: genes expression, phytoplasma, DNA methylation, flower development
Procedia PDF Downloads 3741393 In vitro Control of Aedes aegypti Larvae Using Beauveria bassiana
Authors: R. O. B. Bitencourt, F. S. Farias, M. C. Freitas, C. J. R. Balduino, E.S. Mesquita, A. R. C. Corval, P. S. Gôlo, E. G. Pontes, V. R. E. P. Bittencourt, I. C. Angelo
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Aedes aegypti larval survival rate was assessed after exposure to blastopores or conidia (mineral oil-in-water formulation or aqueous suspension) of Beauveria bassiana CG 479 propagules (blastospores or conidia). Here, mineral oil was used in the fungal formulation to control Aedes aegypti larvae. 1%, 0.5% or 0.1% mineral oil-in-water solutions were used to evaluate mineral oil toxicity for mosquito larvae. In the oil toxicity test, 0.1% mineral oil solution reduced only 4.5% larval survival; accordingly, this concentration was chosen for fungal oil-in-water formulations. Aqueous suspensions were prepared using 0.01% Tween 80® in sterile dechlorinated water. A. aegypti larvae (L2) were exposed in aqueous suspensions or mineral oil-in-water fungal formulations at 1×107 propagules mL-1; the survival rate (assessed daily, for 7 days) and the median survival time (S50) were calculated. Seven days after the treatment, mosquito larvae survival rates were 8.56%, 16.22%, 58%, and 42.56% after exposure to oil-in-water blastospores, oil-in-water conidia, blastospores aqueous suspension and conidia aqueous suspension (respectively). Larvae exposed to 0.01% Tween 80® had 100% survival rate and the ones treated with 0.1% mineral oil-in-water had 95.11% survival rate. Larvae treated with conidia (regardless the presence of oil) or treated with blastospores formulation had survival median time (S50) ranging from one to two days. S50 was not determined (ND) when larvae were exposed to blastospores aqueous suspension, 0.01% Tween 80® (aqueous control) or 0.1% mineral oil-in-water formulation (oil control). B. bassiana conidia and blastospores (mineral oil-in-water formulated or suspended in water) had potential to control A. aegypti mosquito larvae, despite mineral oil-in-water formulation yielded better results in comparison to aqueous suspensions. Here, B. bassiana CG 479 isolate is suggested as a potential biocontrol agent of A. aegypti mosquito larvae.Keywords: blastospores, formulation, mosquitoes, conidia
Procedia PDF Downloads 1881392 Fecundity and Egg Laying in Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae): Model Development and Field Validation
Authors: Muhammad Noor Ul Ane, Dong-Soon Kim, Myron P. Zalucki
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Models can be useful to help understand population dynamics of insects under diverse environmental conditions and in developing strategies to manage pest species better. Adult longevity and fecundity of Helicoverpa armigera (Hübner) were evaluated against a wide range of constant temperatures (15, 20, 25, 30, 35 and 37.5ᵒC). The modified Sharpe and DeMichele model described adult aging rate and was used to estimate adult physiological age. Maximum fecundity of H. armigera was 973 egg/female at 25ᵒC decreasing to 72 eggs/female at 37.5ᵒC. The relationship between adult fecundity and temperature was well described by an extreme value function. Age-specific cumulative oviposition rate and age-specific survival rate were well described by a two-parameter Weibull function and sigmoid function, respectively. An oviposition model was developed using three temperature-dependent components: total fecundity, age-specific oviposition rate, and age-specific survival rate. The oviposition model was validated against independent field data and described the field occurrence pattern of egg population of H. armigera very well. Our model should be a useful component for population modeling of H. armigera and can be independently used for the timing of sprays in management programs of this key pest species.Keywords: cotton bollworm, life table, temperature-dependent adult development, temperature-dependent fecundity
Procedia PDF Downloads 1511391 Integrated Plant Protection Activities against (Tuta absoluta Meyrik) Moth in Tomato Plantings in Azerbaijan
Authors: Nazakat Ismailzada, Carol Jones
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Tomato drilling moth Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the main pest of tomato plants in many countries. The larvae of tomato leaves, the stems inside, in the end buds, they opened the gallery in green and ripe fruit. In this way the harmful products can be fed with all parts of the tomato plant can cause damage to 80-100%. Pest harms all above ground parts of the tomato plant. After the seedlings are planted in areas and during blossoming holder traps with tomato moth’s rubber capsule inside should be placed in the area by using five-tomato moth’s feremon per ha. Then there should be carried out observations in the fields in every three days regularly. During the researches, it was showed that in field condition Carogen 20 SC besides high-level biological efficiency also has low ecological load for environment, and should be used against tomato moth in farms. Therefore it was showed that in field condition Carogen 20 SC besides high-level biological efficiency also has low ecological load for environment, and should be used against tomato moth in farms with insecticide expenditure norm 320 qr\ha. In farms should be used plant rotation, plant fields should be plowed on the 25-30 sm depth, before sowing seeds should be proceeded by insecticides. As element of integrated plant protection activities, should be used pheromones trap. In tomato plant fields as an insecticide should be used AGROSAN 240 SC and Carogen 20 SP.Keywords: lepidoptera, Tuta absoluta, chemical control, integrated pest management
Procedia PDF Downloads 1651390 Steps of the Pancreatic Differentiation in the Grass Snake (Natrix natrix) Embryos
Authors: Magdalena Kowalska, Weronika Rupik
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The pancreas is an important organ present in all vertebrate species. It contains two different tissues, exocrine and endocrine, that act as two glands in one. The development and differentiation of the pancreas in reptiles is poorly known in comparison to other vertebrates. Therefore, the aim of this study was to investigate the particular steps concerning the differentiation of the pancreas in the grass snake (Natrix natrix) embryos. For this, histological methods (including hematoxylin and eosin, and Heidenhain's AZAN staining), transmission electron microscopy and three-dimensional (3D) reconstructions from serial paraffin sections were used. The results of this study indicated that the first step of pancreas development in Natrix was the connection of the two pancreatic buds: dorsal and ventral one. Then, duct walls in both buds started to be remodeled from the multilayered to single-layered epithelium. This remodeling started in the dorsal bud and was simultaneously with the differentiation of the duct lumens which occurred by the cavition. During this process, the cells that had no contact with the mesenchyme underwent cell death named anoikis. These findings indicated that the walls of ducts in the embryonic pancreas of the grass snake were initially formed by the abundant principal and single endocrine cells. Later the basal and goblet cells differentiated. Among the endocrine cells, as the first the B and A cells differentiated, then the D and PP cells. The next step of the pancreatic development was the withdrawing of the endocrine cells from the duct walls to form the pancreatic islets. The endocrine cells and islets were found only in the dorsal part of the pancreas in Natrix embryos what is different than in other vertebrate species. The islets were formed mainly by the A cells. Simultaneously, with the differentiation of the endocrine pancreas, the acinar tissue started to differentiate. The source of the acinar cells were pancreatic ducts similar as in other vertebrates. The acini formation began at the proximal part of the pancreas and went towards the caudal direction. Differentiating pancreatic ducts developed into the branched system that can be divided into extralobular, intralobular, and intercalated ducts, similarly as in other vertebrate species. However, the pattern of branching was different. In conclusions, particular steps of the pancreas differentiation in the grass snake were different than in other vertebrates. It can be supposed that these differences are related to the specific topography of the snake’s internal organs and their taxonomy position. All specimens used in the study were captured according to the Polish regulations concerning the protection of wild species. Permission was granted by the Local Ethics Commission in Katowice (41/2010; 87/2015) and the Regional Directorate for Environmental Protection in Katowice (WPN.6401.257.2015.DC).Keywords: embryogenesis, organogenesis, pancreas, Squamata
Procedia PDF Downloads 1711389 Development of the Squamate Egg Tooth on the Basis of Grass Snake Natrix natrix Studies
Authors: Mateusz Hermyt, Pawel Kaczmarek, Weronika Rupik
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The egg tooth is a crucial structure during hatching of lizards and snakes. In contrast to birds, turtles, crocodiles, and monotremes, egg tooth of squamate reptiles is a true tooth sharing common features of structure and development with all the other teeth of vertebrates. The egg tooth; however, due to its function, exhibits structural differences in relation to regular teeth. External morphology seems to be important in the context of phylogenetic relationships within Squamata but up to date, there is scarce information concerning structure and development of the egg tooth at the submicroscopical level. In presented studies detailed analysis of the egg tooth development in grass snake has been performed with the usage of light (including fluorescent), transmission and scanning electron microscopy. Grass snake embryo’s heads have been used in our studies. Grass snake is common snake species occurring in most of Europe including Poland. The grass snake is characterized by the presence of single unpaired egg tooth (as in most squamates) in contrast to geckos and dibamids possessing paired egg teeth. Studies show changes occurring on the external morphology, tissue and cellular levels of differentiating egg tooth. The egg tooth during its development changes its curvature. Initially, faces directly downward and in the course of its differentiation, it gradually changes to rostro-ventral orientation. Additionally, it forms conical dentinal protrusions on the sides. Histological analysis showed that egg tooth development occurs in similar steps in relation to regular teeth. It undergoes initiation, bud, cap and bell morphological stages. Analyses focused on describing morphological changes in hard tissues (mainly dentin and predentin) of egg tooth and in cells which enamel organ consists of. It included: outer enamel epithelium, stratum intermedium, inner enamel epithelium, odontoblasts, and cells of dental pulp. All specimens used in the study were captured according to the Polish regulations concerning the protection of wild species. Permission was granted by the Local Ethics Commission in Katowice (41/2010; 87/2015) and the Regional Directorate for Environmental Protection in Katowice (WPN.6401.257.2015.DC).Keywords: hatching, organogenesis, reptile, Squamata
Procedia PDF Downloads 1801388 Characteristics of Tremella fuciformis and Annulohypoxylon stygium for Optimal Cultivation Conditions
Authors: Eun-Ji Lee, Hye-Sung Park, Chan-Jung Lee, Won-Sik Kong
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We analyzed the DNA sequence of the ITS (Internal Transcribed Spacer) region of the 18S ribosomal gene and compared it with the gene sequence of T. fuciformis and Hypoxylon sp. in the BLAST database. The sequences of collected T. fuciformis and Hypoxylon sp. have over 99% homology in the T. fuciformis and Hypoxylon sp. sequence BLAST database. In order to select the optimal medium for T. fuciformis, five kinds of a medium such as Potato Dextrose Agar (PDA), Mushroom Complete Medium (MCM), Malt Extract Agar (MEA), Yeast extract (YM), and Compost Extract Dextrose Agar (CDA) were used. T. fuciformis showed the best growth on PDA medium, and Hypoxylon sp. showed the best growth on MCM. So as to investigate the optimum pH and temperature, the pH range was set to pH4 to pH8 and the temperature range was set to 15℃ to 35℃ (5℃ degree intervals). Optimum culture conditions for the T. fuciformis growth were pH5 at 25℃. Hypoxylon sp. were pH6 at 25°C. In order to confirm the most suitable carbon source, we used fructose, galactose, saccharose, soluble starch, inositol, glycerol, xylose, dextrose, lactose, dextrin, Na-CMC, adonitol. Mannitol, mannose, maltose, raffinose, cellobiose, ethanol, salicine, glucose, arabinose. In the optimum carbon source, T. fuciformis is xylose and Hypoxylon sp. is arabinose. Using the column test, we confirmed sawdust a suitable for T. fuciformis, since the composition of sawdust affects the growth of fruiting bodies of T. fuciformis. The sawdust we used is oak tree, pine tree, poplar, birch, cottonseed meal, cottonseed hull. In artificial cultivation of T. fuciformis with sawdust medium, T. fuciformis and Hypoxylon sp. showed fast mycelial growth on mixture of oak tree sawdust, cottonseed hull, and wheat bran.Keywords: cultivation, optimal condition, tremella fuciformis, nutritional source
Procedia PDF Downloads 2101387 Low Dose In-Line Electron Holography for 3D Atomic Resolution Tomography of Soft Materials
Authors: F. R. Chen, C. Kisielowski, D. Van Dyck
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In principle, the latest generation aberration-corrected transmission electron microscopes (TEMs) could achieve sub-Å resolution, but there is bottleneck that hinders the final step towards revealing 3D structure. Firstly, in order to achieve a resolution around 1 Å with single atom sensitivity, the electron dose rate needs to be sufficiently large (10⁴-10⁵eÅ⁻² s⁻¹). With such large dose rate, the electron beam can induce surfaces alterations or even bulk modifications, in particular, for electron beam sensitive (soft) materials such as nm size particles, organic materials, proteins or macro-molecules. We will demonstrate methodology of low dose electron holography for observing 3D structure for soft materials such as single Oleic acid molecules at atomic resolution. The main improvement of this new type of electron holography is based on two concepts. Firstly, the total electron dose is distributed over many images obtained at different defocus values from which the electron hologram is then reconstructed. Secondly, in contrast to the current tomographic methods that require projections from several directions, the 3D structural information of the nano-object is then extracted from this one hologram obtained from only one viewing direction.Keywords: low dose electron microscopy, in-line electron holography, atomic resolution tomography, soft materials
Procedia PDF Downloads 1921386 Influence of Settlements and Human Activities on Beetle Diversity and Assemblage Structure at Small Islands of the Kepulauan Seribu Marine National Park and Nearby Java
Authors: Shinta Holdsworth, Jan Axmacher, Darren J. Mann
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Beetles represent the most diverse insect taxon, and they contribute significantly to a wide range of vital ecological functions. Examples include decomposition by bark beetles, nitrogen recycling and dung processing by dung beetles or pest control by predatory ground beetles. Nonetheless, research into the distribution patterns, species richness and functional diversity of beetles particularly from tropical regions remains extremely limited. In our research, we aim to investigate the distribution and diversity patterns of beetles and the roles they play in small tropical island ecosystems in the Kepulauan Seribu Marine National Park and on Java. Our research furthermore provides insights into the effects anthropogenic activities have on the assemblage composition and diversity of beetles on the small islands. We recorded a substantial number of highly abundant small island species, including a substantial number of unique small island species across the study area, highlighting these islands’ potential importance for the regional conservation of genetic resources. The highly varied patterns observed in relation to the use of different trapping types - pitfall traps and flight interception traps (FITs) - underscores the need for complementary trapping strategies that combine multiple methods for beetle community surveys in tropical islands. The significant impacts of human activities have on the small island beetle faunas were also highlighted in our research. More island beetle species encountered in settlement than forest areas shows clear trend of positive links between anthropogenic activities and the overall beetle species richness. However, undisturbed forests harboured a high number of unique species, also in comparison to disturbed forests. Finally, our study suggests that, with regards to different feeding guilds, the diversity of herbivorous beetles on islands is strongly affected by the different levels of forest cover encountered.Keywords: beetle diversity, forest disturbance, island biogeography, island settlement
Procedia PDF Downloads 2201385 Characterization of Porosity and Flow in Solid Oxide Fuel Cell with 3D Focused Ion Beam Serial Slicing
Authors: Daniel Phifer, Anna Prokhodtseva
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DualBeam (FIB-SEM) has long been the technology of choice to sub-sample and characterize materials at site-specific locations which are difficult or impossible to extract by conventional embedding/polishing methods. Whereas Ga based FIB provides excellent resolution and enables precise material removal, the current is usually limited and only allows the extraction of small material biopsies typically ranging from 5-70um wide. Xe Plasma FIB, by contrast, has around 38x more current and can remove more material at the same time to extract significant sized chunks (100-1000um) of materials for further analysis. This increased volume has enabled time-prohibitive investigations like large grain 3D serial sectioning and EBSD and micro-machining for micro-mechanical testing. Investigation of the pore spaces with 3D modeling can determine the relative characteristics of the materials to help design or select properties for best function. Pore spaces can be described with a tortuosity number which is calculated by modules in the 3D analysis software. Xe Plasma FIB technology provides a workflow with sufficient volume to characterize porosity when both large-volume 3D materials characterization and nanometer resolution is required to understand the system.Keywords: dual-beam, FIB-SEM, porosity, SOFC, solid oxide fuel cell
Procedia PDF Downloads 2071384 Characteristics of Oak Mushroom Cultivar, Bambithyang Developed by Golden Seed Project
Authors: Yeongseon Jang, Rhim Ryoo, Young-Ae Park, Kang-Hyeon Ka, Donha Choi, Sung-Suk Lee
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Lentinula edodes (Berk.) Pegler, oak mushroom, is one of the most largely produced mushrooms in the world. To increase the competitiveness of Korean oak mushroom, golden seed project is ongoing. In this project, we develop new oak mushroom varieties to increase its productivity, quality, disease resistance, and so on. Through the project, new oak mushroom cultivar, Bambithyang was developed by mono-mono hybridization method. The optimum temperature for mycelial growth was at 25°C on potato dextrose agar (PDA) media. For the mass production test, it was cultivated using sawdust media with sawdust block type for 100 days. The temperature for primordia formation and fruit body production was broad (between 11°C and 20°C) which is good for spring and fall. Each flush period lasted for 6-7 days and the highest fruit body production was recorded in the first flush. The fruiting is sporadic. The pileus was deep brown. Its diameter was 69.2 mm and width was 17.8 mm. The stipe was ivory. It was 14.7 mm thick and 54.7 mm long. We would continue to develop new varieties while increasing the market share of domestic spawn with this variety.Keywords: Lentinula edodes, mono-mono hybridization, new cultivar, oak mushroom
Procedia PDF Downloads 3461383 Tunisian Dung Beetles Fauna: Composition and Biogeographic Affinities
Authors: Imen Labidi, Said Nouira
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Dung beetles Scarabaeides of Tunisia constitute a major component of soil fauna, especially in the Mediterranean region. In the first phase of the present study, an intensive investigation of this group following the gathering of all the bibliographic, museological data and based on a recent collection of 17020 specimens in 106 localities in Tunisia, allowed to confirm with certainty the presence of 94 species distributed in 43 genera, 4 families and 3 sub-families. Only 81 species distributed in 38 genres, 4 families, and 3 sub-families, have been found during our prospections. The population of dung beetles Scarabaeides is composed of 58% of Aphodiidae, 39.51% of Scarabaeidae, and 8.64% of Geotrupidae. Biogeographic affinities of the species were determined and showed that 42% of the identified species have a wide Palaearctic distribution, the endemism is very low, only 3 species are endemic to Tunisia Mecynodes demoflysi, Neobodilus marani, and Thorectes demoflysi, 29 species have a wide distribution, 35 are northern and 17 are southern species. Moreover, others are dependent on very specific Biotopes like Sisyphus schaefferi linked to the northwest of Tunisia and Scarabaeus semipunctatus related to the coastal area north of Tunisia.Keywords: dung beetles, Tunisia, composition, biogeography
Procedia PDF Downloads 2491382 Insecticidal Activity of Piper aduncum Fruit and Tephrosia vogelii Leaf Mixed Formulations against Cabbage Pest Plutella xylostella (L.) (Lepidoptera: Plutellidae)
Authors: Eka Candra Lina, Indah Widhianingrum, Mita Eka Putri, Nur Afni Evalia, Muhammad Makky
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The emulsifiable concentrate (EC) and wettable powder (WP) of Piper aduncum and Tephrosia vogelii mixed formulations were tested for their activities in the laboratory and their effectiveness in the field against cabbage pest Plutella xyostella. Cabbage leaves soaked in six different mixed formulation concentrations were tested to 2ⁿᵈ instar larvae of P. xylostella with six replications. The observation was conducted everyday until larvae reached 4ᵗʰ instar stage. Correlation between concentration and larvae mortality was analyzed using probit (POLO-PC). The survived larvae was observed by looking at the growth and development, as well as the antifeedant effects. Field efficacy test was based on LC₉₅ value from laboratory test result. The experiment used a randomized block design with 5 treatments and 3 replications to test the populations of P. xylostella larvae and insecticide effectivity. The results showed that the EC and WP mixed formulations showed insecticidal activity against P. xylostella larvae, with LC₉₅ value of 0.35% and 0.37%, respectively. The highest antifeedant effect on EC mixed formulation was 85.01% and WP mixed formulation was 86.23%. Both mixed formulations also slowed the development of larvae when compared with control. Field effication result showed that applications of EC mixed formulation were able to restrain the population of P. xylostella, with effectivity value of 71.06%. Insecticide effectivity value of EC mixed formulation was higher than WP mixed formulation and Bacillus thuringiensis formulation.Keywords: botanical insecticide, efficacy, emulsifiable concentrate (EC), Plutella xylostella, wettable powder (WP)
Procedia PDF Downloads 2431381 Protective Effect of Rosemary Extract against Toxicity Induced by Egyptian Naja haje Venom
Authors: Walaa H. Salama, Azza M. Abdel-Aty, Afaf S. Fahmy
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Background: Egyptian Cobra; Naja haje (Elapidae) is one of most common snakes, widely distributed in Egypt and its envenomation causes multi-organ failure leading to rapid death. Thus, Different medicinal plants showed a protective effect against venom toxicity and may complement the conventional antivenom therapy. Aim: The present study was designed to assess both the antioxidant capacity of methanolic extract of rosemary leaves and evaluate the neutralizing ability of the extract against hepatotoxicity induced by Naja haje venom. Methods: The total phenolic and flavonoid contents and the antioxidant capacity of the methanolic rosemary extract were estimated by DPPH and ABTS Scavenging methods. In addition, the rosemary extract were assessed for anti-venom properties under in vitro and in vivo standard assays. Results: The rosemary extract had high total phenolic and flavonoid content as 12 ± 2 g of gallic acid equivalent per 100 gram of dry weight (g GAE/100g dw) and 5.5 ± 0.8 g of catechin equivalent per 100 grams of dry weight (g CE/100g dw), respectively. In addition, the rosemary extract showed high antioxidant capacity. Furthermore, The rosemary extract were inhibited in vitro the enzymatic activities of phospholipase A₂, L-amino acid oxidase, and hyaluronidase of the venom in a dose-dependent manner. Moreover, indirect hemolytic activity, hepatotoxicity induced by venom were completely neutralized as shown by histological studies. Conclusion: The phenolic compounds of rosemary extract with potential antioxidant activity may be considered as a promising candidate for future therapeutics in snakebite therapy.Keywords: antioxidant activity, neutralization, phospholipase A₂ enzyme, snake venom
Procedia PDF Downloads 1821380 Wireworms under the Sword of Damocles: Attraction to Maize Root Volatiles
Authors: Diana La Forgia, Jean Baptiste Thibord, François Verheggen
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Volatiles Organic Compound (VOCs) are one of the many features of defense used by plants in their eternal fight against pests. Their main role is to attract the natural enemies of the herbivores. But on another hand, they can be used by the same herbivores to locate plants while foraging. In an attempt to fill a gap of knowledge in a complex web of interactions, we focused on wireworms (Coleoptera:Elateridae). Wireworms whose larvae feed on roots are one of the most spread pests of valuable crops such as maize and potatoes, causing important economical damage. Little is known about the root compounds that are playing a role in the attraction of the larvae. In order to know more about these compounds, we compared four different maize varieties (Zea mays mays) that are known to have different levels of attraction, from weak to strong, for wireworms in fields. We tested the attraction of larvae in laboratory conditions in dual-choice olfactometer assays where they were offered all possible combinations of the four maize varieties. Contemporary, we collected the VOCs of each variety during 24h using a push-and-pull system. The collected samples were then analyzed by gas chromatography coupled with a mass spectrometer (GC-MS) to identify their molecular profiles. The choice of the larvae was dependent on the offered combination and some varieties were preferred to others. Differences were also observed in terms of quantitative and qualitative emissions of volatile profiles between the maize varieties. Our aim is to develop traps based on VOCs from maize roots to open a new frontier in wireworms management.Keywords: integrated pest management, maize roots, plant defense, volatile organic compounds, wireworms
Procedia PDF Downloads 1551379 Prioritizing Biodiversity Conservation Areas based on the Vulnerability and the Irreplaceability Framework in Mexico
Authors: Alma Mendoza-Ponce, Rogelio Corona-Núñez, Florian Kraxner
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Mexico is a megadiverse country and it has nearly halved its natural vegetation in the last century due to agricultural and livestock expansion. Impacts of land use cover change and climate change are unevenly distributed and spatial prioritization to minimize the affectations on biodiversity is crucial. Global and national efforts for prioritizing biodiversity conservation show that ~33% to 45% of Mexico should be protected. The width of these targets makes difficult to lead resources. We use a framework based on vulnerability and irreplaceability to prioritize conservation efforts in Mexico. Vulnerability considered exposure, sensitivity and adaptive capacity under two scenarios (business as usual, BAU based, on the SSP2 and RCP 4.5 and a Green scenario, based on the SSP1 and the RCP 2.6). Exposure to land use is the magnitude of change from natural vegetation to anthropogenic covers while exposure to climate change is the difference between current and future values for both scenarios. Sensitivity was considered as the number of endemic species of terrestrial vertebrates which are critically endangered and endangered. Adaptive capacity is used as the ration between the percentage of converted area (natural to anthropogenic) and the percentage of protected area at municipality level. The results suggest that by 2050, between 11.6 and 13.9% of Mexico show vulnerability ≥ 50%, and by 2070, between 12.0 and 14.8%, in the Green and BAU scenario, respectively. From an ecosystem perspective cloud forests, followed by tropical dry forests, natural grasslands and temperate forests will be the most vulnerable (≥ 50%). Amphibians are the most threatened vertebrates; 62% of the endemic amphibians are critically endangered or endangered while 39%, 12% and 9% of the mammals, birds, and reptiles, respectively. However, the distribution of these amphibians counts for only 3.3% of the country, while mammals, birds, and reptiles in these categories represent 10%, 16% and 29% of Mexico. There are 5 municipalities out of the 2,457 that Mexico has that represent 31% of the most vulnerable areas (70%).These municipalities account for 0.05% of Mexico. This multiscale approach can be used to address resources to conservation targets as ecosystems, municipalities or species considering land use cover change, climate change and biodiversity uniqueness.Keywords: biodiversity, climate change, land use change, Mexico, vulnerability
Procedia PDF Downloads 1671378 Molecular Dissection of Late Flowering under a Photoperiod-Insensitive Genetic Background in Soybean
Authors: Fei Sun, Meilan Xu, Jianghui Zhu, Maria Stefanie Dwiyanti, Cheolwoo Park, Fanjiang Kong, Baohui Liu, Tetsuya Yamada, Jun Abe
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Reduced or lack of sensitivity to long daylengths is a key character for soybean, a short-day crop, to adapt to higher latitudinal environments. However, the photoperiod-insensitivity often results in a reduction of the duration of vegetative growth and final yield. To overcome this limitation, a photoperiod insensitive line (RIL16) was developed in this study that delayed flowering from the recombinant inbred population derived from a cross between a photoperiod-insensitive cultivar AGS292 and a late-flowering Thai cultivar K3. Expression analyses under SD and LD conditions revealed that the expression levels of FLOWERING LOCUS T (FT) orthologues, FT2a and FT5a, were lowered in RIL16 relative to AGS292, although the expression of E1, a soybean-specific suppressor for FTs, was inhibited in both conditions. A soybean orthologue of TARGET OF EAT1 (TOE1), another suppressor of FT, showed an upregulated expression in RIL16, which appeared to reflect a lower expression of miR172a. Our data suggest that the delayed flowering of RIL16 most likely is controlled by genes involved in an age-dependent pathway in flowering. The QTL analysis based on 1,125 SNPs obtained from Restriction Site Associated DNA Sequencing revealed two major QTLs for flowering dates in Chromosome 16 and two minor QTLs in Chromosome 4, all of which accounted for 55% and 48% of the whole variations observed in natural day length and artificially-induced long day length conditions, respectively. The intervals of the major QTLs harbored FT2a and FT5a, respectively, on the basis of annotated genes in the Williams 82 reference genome. Sequencing analysis further revealed a nonsynonymous mutation in FT2a and an SNP in the 3′ UTR region of FT5a. A further study may elucidate a detailed mechanism underlying the QTL for late flowering. The alleles from K3 at the two QTLs can be used singly or in combination to retain an appropriate duration of vegetative growth to maximize the final yield of photoperiod-insensitive soybeans.Keywords: FT genes, miR72a, photoperiod-insensitive, soybean flowering
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