Abstracts | Bioengineering and Life Sciences
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2157

World Academy of Science, Engineering and Technology

[Bioengineering and Life Sciences]

Online ISSN : 1307-6892

1257 Spatial Distribution of Virus-Transmitting Aphids of Plants in Al Bahah Province, Saudi Arabia

Authors: Sabir Hussain, Muhammad Naeem, Yousif Aldryhim, Susan E. Halbert, Qingjun Wu

Abstract:

Plant viruses annually cause severe economic losses in crop production and globally, different aphid species are responsible for the transmission of such viruses. Additionally, aphids are also serious pests of trees, and agricultural crops. Al Bahah Province, Kingdom of Saudi Arabia (KSA) has a high native and introduced plant species with a temperate climate that provides ample habitats for aphids. In this study, we surveyed virus-transmitting aphids from the Province to highlight their spatial distributions and hot spot areas for their target control strategies. During our fifteen month's survey in Al Bahah Province, three hundred and seventy samples of aphids were collected using both beating sheets and yellow water pan traps. Consequently, fifty-four aphid species representing 30 genera belonging to four families were recorded from Al Bahah Province. Alarmingly, 35 aphid species from our records are virus transmitting species. The most common virus transmitting aphid species based on number of collecting samples, were Macrosiphum euphorbiae (Thomas, 1878), Brachycaudus rumexicolens (Patch, 1917), Uroleucon sonchi (Linnaeus, 1767), Brachycaudus helichrysi (Kaltenbach, 1843), and Myzus persicae (Sulzer, 1776). The numbers of samples for the forementioned species were 66, 24, 23, 22, and 20, respectively. The widest range of plant hosts were found for M. euphorbiae (39 plant species), B. helichrysi (12 plant species), M. persicae (12 plant species), B. rumexicolens (10 plant species), and U. sonchi (9 plant species). The hottest spot areas were found in Al-Baha, Al Mekhwah and Biljarashi cities of the province on the basis of their abundance. This study indicated that Al Bahah Province has relatively rich aphid diversity due to the relatively high plant diversity in a favorable climatic condition. ArcGIS tools can be helpful for biologists to implement the target control strategies against these pests in the integrated pest management, and ultimately to save money and time.

Keywords: Al Bahah province, aphid-virus interaction, biodiversity, global information system

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1256 Microbial Pathogens Associated with Banded Sugar Ants (Camponotus consobrinus) in Calabar, Nigeria

Authors: Ofonime Ogba, Augustine Akpan

Abstract:

Objectives and Goals: The study was aimed at determining pathogenic microbial carriage on the external body parts of Camponotus consobrinus which is also known as the banded sugar ant because of its liking for sugar and sweet food. The level of pathogenic microbial carriage of Camponotus consobrinus in association to the environment in which they have been collected is not known. Methods: The ants were purposively collected from four locations including the kitchens, bedroom of various homes, food shops, and bakeries. The sample collection took place within the hours of 6:30 pm to 11:00 pm. The ants were trapped in transparent plastic containers of which sugar, pineapple peels, sugar cane and soft drinks were used as bait. The ants were removed with a sterile spatula and put in 10mls of peptone water in sterile universal bottles. The containers were vigorously shaken to wash the external surface of the ant. It was left overnight and transported to the Microbiology Laboratory, University of Calabar Teaching Hospital for analysis. The overnight peptone broths were inoculated on Chocolate agar, Blood agar, Cystine Lactose Electrolyte-Deficient agar (CLED) and Sabouraud dextrose agar. Incubation was done aerobically and in a carbon dioxide jar for 24 to 48 hours at 37°C. Isolates were identified based on colonial characteristics, Gram staining, and biochemical tests. Results: Out of the 250 Camponotus consobrinus caught for the study, 90(36.0%) were caught in the kitchen, 75(30.0%) in the bedrooms 40(16.0%) in the bakery while 45(18.0%) were caught in the shops. A total of 82.0% prevalence of different microbial isolates was associated with the ants. The kitchen had the highest number of isolates 75(36.6%) followed by the bedroom 55(26.8%) while the bakery recorded the lowest number of isolates 35(17.1%). The profile of micro-organisms associated with Camponotus consobrinus was Escherichia coli 73(30.0%), Morganella morganii 45(18.0%), Candida species 25(10.0%), Serratia marcescens 10(4.0%) and Citrobacter freundii 10(4.0%). Conclusion: Most of the Camponotus consobrinus examined in the four locations harboured potential pathogens. The presence of ants in homes and shops can facilitate the propagation and spread of pathogenic microorganisms. Therefore, the development of basic preventive measures and the control of ants must be taken seriously.

Keywords: Camponotus consobrinus, potential pathogens, microbial isolates, spread

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1255 Identification and Characterization of Novel Genes Involved in Quinone Synthesis in the Odoriferous Defensive Stink Glands of the Red Flour Beetle, Tribolium castaneum

Authors: B. Atika, S. Lehmann, E. Wimmer

Abstract:

The defense strategy is very common in the insect world. Defensive substances play a wide variety of functions for beetles, such as repellents, toxicants, insecticides, and antimicrobics. Beetles react to predators, invaders, and parasitic microbes with the release of toxic and repellent substances. Defensive substances are directed against a large array of potential target organisms or may function for boiling bombardment or as surfactants. Usually, Coleoptera biosynthesize and store their defensive compounds in a complex secretory organ, known as odoriferous defensive stink glands. The red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae), uses these glands to produce antimicrobial p-benzoquinones and 1-alkenes. In the past, the morphology of stink gland has been studied in detail in tenebrionid beetles; however, very little is known about the genes that are involved in the production of gland secretion. In this study, we studied a subset of genes that are essential for the benzoquinone production in red flour beetle. In the first phase, we selected 74 potential candidate genes from a genome-wide RNA interference (RNAi) knockdown screen named 'iBeetle.' All these 74 candidate genes were functionally characterized by RNAi-mediated gene knockdown. Therefore, they were selected for a subsequent gas chromatography-mass spectrometry (GC-MS) analysis of secretion volatiles in respective RNAi knockdown glands. 33 of them were observed to alter the phenotype of stink gland. In the GC-MS analysis, 7 candidate genes were noted to display a strongly altered gland, in terms of secretion color and chemical composition, upon knockdown, showing their key role in the biosynthesis of gland secretion. Morphologically altered stink glands were found for odorant receptor and protein kinase superfamily. Subsequent GC-MS analysis of secretion volatiles revealed reduced benzoquinone levels in LIM domain, PDZ domain, PBP/GOBP family knockdowns and a complete lack of benzoquinones in the knockdown of sulfatase-modifying factor enzyme 1, sulfate transporter family. Based on stink gland transcriptome data, we analyzed the function of sulfatase-modifying factor enzyme 1 and sulfate transporter family via RNAi-mediated gene knockdowns, GC-MS, in situ hybridization, and enzymatic activity assays. Morphologically altered stink glands were noted in knockdown of both these genes. Furthermore, GC-MS analysis of secretion volatiles showed a complete lack of benzoquinones in the knockdown of these two genes. In situ hybridization showed that these two genes are expressed around the vesicle of certain subgroup of secretory stink gland cells. Enzymatic activity assays on stink gland tissue showed that these genes are involved in p-benzoquinone biosynthesis. These results suggest that sulfatase-modifying factor enzyme 1 and sulfate transporter family play a role specifically in benzoquinone biosynthesis in red flour beetles.

Keywords: Red Flour Beetle, defensive stink gland, benzoquinones, sulfate transporter, sulfatase-modifying factor enzyme 1

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1254 Development of Beeswax-Discharge Writing Material for Visually Impaired Persons

Authors: K. Doi, T. Nishimura, H. Fujimoto, T. Tanaka

Abstract:

It has been known that visually impaired persons have some problems in getting visual information. Therefore, information accessibility for the visually impaired persons is very important in a current information society. Some application software with read-aloud function for using personal computer and smartphone are getting more and more popular among visually impaired persons in the world. On the other hand, it is also very important for being able to learn how to read and write characters such as Braille and Visual character. Braille typewriter has been widely used in learning Braille. And also raised-line drawing kits as writing material has been used for decades for especially acquired visually impaired persons. However, there are some drawbacks such as the drawn line cannot be erased. Moreover, visibility of drawing lines is not so good for visually impaired with low vision. We had significant number of requests for developing new writing material for especially acquired visually impaired persons instead of raised-line drawing kits. For conducting development research of novel writing material, we could receive a research grant from ministry of health, labor and welfare in Japanese government. In this research, we developed writing material typed pens and pencils with Beeswax-discharge instead of conventional raised-line drawing kits. This writing material was equipped with cartridge heater for melting beeswax and its heat controller. When this pen users held down the pen tip on the regular paper such as fine paper and so on, the melted beeswax could be discharged from pen tip with valve structure. The beeswax was discharged at 100 gf of holding down force based on results of our previous trial study. The shape of pen tip was semispherical for becoming low friction between pen tip and surface of paper. We conducted one basic experiment to evaluate influence of the curvature of pen tip on ease to write. Concretely, the conditions of curvature was 0.15, 0.35, 0.50, 1.00 mm. The following four interval scales were used as indexes of subjective assessment during writing such as feeling of smooth motion of pen, feeling of comfortable writing, sense of security and feeling of writing fatigue. Ten subjects were asked to participate in this experiment. The results reveal that subjects could draw easily when the radius of the pen tip was 1.00 mm, and lines drawn with beeswax-discharge writing material were easy to perceive.

Keywords: beeswax-discharge writing material, raised-line drawing kits, visually impaired persons, pen tip

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1253 Host Range and Taxonomy of Hairy Caterpillars (Erebidae: Lepidoptera) in Different Cropping Ecosystems

Authors: Mallikarjun Warad, C. M. Kalleshwaraswamy, P. R. Shashank

Abstract:

Studies were conducted to record the occurrence of different species of hairy caterpillar on different host plants in and around Shivamogga, Karnataka, India. Twelve genera of hairy caterpillars belonging to Arctiinae and Lymantriinae were recorded on different host plants and reared to adults in laboratory on their respective hosts. The Porthesia sp. feed on castor, Creatonotus gangis on cocoa, Perina nuda on fig, Pericalia ricini on pigeon pea, Utetheisa pulchella on sunhemp and Euproctis sp. on paddy and banana. Illustrations of immature and adults were made to associate them. Along with this, light traps were also set during the rainy season, to capture adults of hairy caterpillars. An illustrated identification key was provided for easy and accurate identification of adult of hairy caterpillars based on their morphological (male genitalial) characters. The study through a light on the existence of sexual dimorphism, polyphagous nature and diapause are the major hindrance in taxonomic identification. Hence, attempts were made to address these issues in the study.

Keywords: Erebidae, hairy caterpillars, male genitalia, taxonomy

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1252 Influence of Readability of Paper-Based Braille on Vertical and Horizontal Dot Spacing in Braille Beginners

Authors: K. Doi, T. Nishimura, H. Fujimoto

Abstract:

The number of people who become visually impaired and do not have sufficient tactile experiences has increased by various disease. Especially, many acquired visually impaired persons due to accidents, disorders, and aging cannot adequately read Braille. It is known that learning Braille requires a great deal of time and the acquisition of various skills. In our previous studies, we reported one of the problems in learning Braille. Concretely, the standard Braille size is too small for Braille beginners. And also we are short of the objective data regarding easily readable Braille size. Therefore, it is necessary to conduct various experiments for evaluating Braille size that would make learning easier for beginners. In this study, for the purpose of investigating easy-to-read conditions of vertical and horizontal dot spacing for beginners, we conducted one Braille reading experiment. In this our experiment, we prepared test pieces by use of our original Braille printer with controlling function of Braille size. We specifically considered Braille beginners with acquired visual impairments who were unfamiliar with Braille. Therefore, ten sighted subjects with no experience of reading Braille participated in this experiment. Size of vertical and horizontal dot spacing was following conditions. Each dot spacing was 2.0, 2.3, 2.5, 2.7, 2.9, 3.1mm. The subjects were asked to read one Braille character with controlled Braille size. The results of this experiment reveal that Braille beginners can read Braille accurately and quickly when both vertical and horizontal dot spacing are 3.1 mm or more. This knowledge will be helpful data in considering Braille size for acquired visually impaired persons.

Keywords: paper-based Braille, vertical and horizontal dot spacing, readability, acquired visual impairment, Braille beginner

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1251 Entomological Survey of Mosquitoes Responsible for the Transmission of Lymphatic Filariasis in Biase Cross River State, Nigeria

Authors: Maurice Mbah

Abstract:

Entomological survey of mosquitoes responsible for the transmission of lymphatic filariasis in Biase Local Government area of Cross River State, Nigeria within March and June 2017. Lymphatic filariasis is a mosquito-borne parasitic disease that is caused by three species of tissue dwelling filaroids (Wuchereria bancrofti; Brugia malayi; Brugia timori): Wuchereria bancrofti is responsible for 90% of cases and is found throughout the tropics and in some sub-tropical areas worldwide. The mosquitoes were caught using human landing catches, and pyrethrum spray catches method. The entomological analysis of mosquitoes which include speciating into genus and dissecting them to unveil any microfilaria in the thoracic region, abdomen, and mouth parts of the mosquitoes. Entomological analysis shows that, from the 1296 mosquitoes caught 795 (61.3%) were Culex species, 342 (26.4%) Anopheles species, 102 (7.9%) Aedes species, and 57 (4.4%) of other Genera. There was a statistically significant difference in the number of mosquitoes caught in the dry and rainy season (X²=0.62, P < 0.05). Out of 1213 mosquitoes dissected, 24(0.02%) contained developed stages (L₁ – L₃) of W. bancrofti larvae. 13 (0.01%) of the infected mosquitoes were of Culex species, and Anopheles species accounted for the other 11 (0.009%). There was a statistically significant difference in the infection rate between the two seasons (X²=0.87, P < 0.05). The correlation analysis showed a positive correlation between the infection rate among mosquitoes in the dry and rainy season (r=0.85, P < 0.05). The entomological studies showed that Anopheles species and the Culex species are the vectors of lymphatic filariasis in the study area.

Keywords: entomological survey, mosquitoes, lymphatic filariasis, biase

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1250 Basic Examination of Easily Distinguishable Tactile Symbols Attached to Containers and Packaging

Authors: T. Nishimura, K. Doi, H. Fujimoto, Y. Hoshikawa, T. Wada

Abstract:

In Japan, it is expected that reasonable accommodation for persons with disabilities will progress further. In particular, there is an urgent need to enhance information support for visually impaired persons who have difficulty accessing information. Recently, tactile symbols have been attached to various surfaces, such as the content labels of containers and packaging of various everyday products. The advantage of tactile symbols is that they are useful for visually impaired persons who cannot read Braille. The method of displaying tactile symbols is prescribed by the International Organization for Standardization (ISO). However, the quantitative data on the shapes and dimensions of tactile symbols is insufficient. In this study, through an evaluation experiments, we examine the easy-to-distinguish shapes and dimensions of tactile symbols used for various applications, including the content labels on containers and packaging. Visually impaired persons participated in the experiments. They used tactile symbols on a daily basis. The details and processes of the experiments were orally explained to the participants prior to the experiments, and the informed consent of the participants was obtained. They were instructed to touch the test pieces of tactile symbols freely with both hands. These tactile symbols were selected because they were likely to be easily distinguishable symbols on the content labels of top surfaces of containers and packaging based on a hearing survey that involved employees of an organization of visually impaired and a social welfare corporation, as well as academic experts of support technology for visually impaired. The participants then answered questions related to ease of distinguishing of tactile symbols on a scale of 5 (where 1 corresponded to ‘difficult to distinguish’ and 5 corresponded to ‘easy to distinguish’). Hearing surveys were also performed in an oral free answer manner with the participants after the experiments. This study revealed the shapes and dimensions regarding easily distinguishable tactile symbols attached to containers and packaging. We expect that this knowledge contributes to improvement of the quality of life of visually impaired persons.

Keywords: visual impairment, accessible design, tactile symbol, containers and packaging

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1249 Relationship between Thumb Length and Pointing Performance on Portable Terminal with Touch-Sensitive Screen

Authors: Takahiro Nishimura, Kouki Doi, Hiroshi Fujimoto

Abstract:

Touch-sensitive screens that serve as displays and input devices have been adopted in many portable terminals such as smartphones and personal media players, and the market of touch-sensitive screens has expanded greatly. One of the advantages of touch-sensitive screen is the flexibility in the graphical user interface (GUI) design, and it is imperative to design an appropriate GUI to realize an easy-to-use interface. Moreover, it is important to evaluate the relationship between pointing performance and GUI design. There is much knowledge regarding easy-to-use GUI designs for portable terminals with touch-sensitive screens, and most have focused on GUI design approaches for women or children with small hands. In contrast, GUI design approaches for users with large hands have not received sufficient attention. In this study, to obtain knowledge that contributes to the establishment of individualized easy-to-use GUI design guidelines, we conducted experiments to investigate the relationship between thumb length and pointing performance on portable terminals with touch-sensitive screens. In this study, fourteen college students who participated in the experiment were divided into two groups based on the length of their thumbs. Specifically, we categorized the participants into two groups, thumbs longer than 64.2 mm into L (Long) group, and thumbs longer than 57.4 mm but shorter than 64.2 mm into A (Average) group, based on Japanese anthropometric database. They took part in this study under the authorization of Waseda University’s ‘Ethics Review Committee on Research with Human Subjects’. We created an application for the experimental task and implemented it on the projected capacitive touch-sensitive screen portable terminal (iPod touch (4th generation)). The display size was 3.5 inch and 960 × 640 - pixel resolution at 326 ppi (pixels per inch). This terminal was selected as the experimental device, because of its wide use and market share. The operational procedure of the application is as follows. First, the participants placed their thumb on the start position. Then, one cross-shaped target in a 10 × 7 array of 70 positions appeared at random. The participants pointed the target with their thumb as accurately and as fast as possible. Then, they returned their thumb to the start position and waited. The operation ended when this procedure had been repeated until all 70 targets had each been pointed at once by the participants. We adopted the evaluation indices for absolute error, variable error, and pointing time to investigate pointing performance when using the portable terminal. The results showed that pointing performance varied with thumb length. In particular, on the lower right side of the screen, the performance of L group with long thumb was low. Further, we presented an approach for designing easy-to- use button GUI for users with long thumbs. The contributions of this study include revelation of the relationship between pointing performance and user’s thumb length when using a portable terminal in terms of accuracy, precision, and speed of pointing. We hope that these findings contribute to an easy-to-use GUI design for users with large hands.

Keywords: pointing performance, portable terminal, thumb length, touch-sensitive screen

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1248 Epigenetic Modifying Potential of Dietary Spices: Link to Cure Complex Diseases

Authors: Jeena Gupta

Abstract:

In the today’s world of pharmaceutical products, one should not forget the healing properties of inexpensive food materials especially spices. They are known to possess hidden pharmaceutical ingredients, imparting them the qualities of being anti-microbial, anti-oxidant, anti-inflammatory and anti-carcinogenic. Further aberrant epigenetic regulatory mechanisms like DNA methylation, histone modifications or altered microRNA expression patterns, which regulates gene expression without changing DNA sequence, contribute significantly in the development of various diseases. Changing lifestyles and diets exert their effect by influencing these epigenetic mechanisms which are thus the target of dietary phytochemicals. Bioactive components of plants have been in use since ages but their potential to reverse epigenetic alterations and prevention against diseases is yet to be explored. Spices being rich repositories of many bioactive constituents are responsible for providing them unique aroma and taste. Some spices like curcuma and garlic have been well evaluated for their epigenetic regulatory potential, but for others, it is largely unknown. We have evaluated the biological activity of phyto-active components of Fennel, Cardamom and Fenugreek by in silico molecular modeling, in vitro and in vivo studies. Ligand-based similarity studies were conducted to identify structurally similar compounds to understand their biological phenomenon. The database searching has been done by using Fenchone from fennel, Sabinene from cardamom and protodioscin from fenugreek as a query molecule in the different small molecule databases. Moreover, the results of the database searching exhibited that these compounds are having potential binding with the different targets found in the Protein Data Bank. Further in addition to being epigenetic modifiers, in vitro study had demonstrated the antimicrobial, antifungal, antioxidant and cytotoxicity protective effects of Fenchone, Sabinene and Protodioscin. To best of our knowledge, such type of studies facilitate the target fishing as well as making the roadmap in drug design and discovery process for identification of novel therapeutics.

Keywords: epigenetics, spices, phytochemicals, fenchone

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1247 Innate Immunity of Insects in Brief

Authors: Ehsan Soleymaninejadian

Abstract:

As the field of immunology is growing day by day, and its chaotic system amazes more people, greed of research in this area is growing; however dealing with human or mammalian cells such as mice make the research expensive. Although there are some differences between higher animals with insects, importance of innate immunity during evolution made it untouched. So, for understanding the innate immunity insects can be good models. They are cheap; reproduction is fast and in the case genetics, less complicated. In this review, we tried to briefly tackle with important factors in insects’ innate immunity such as melanization, encapsulation, JAK-STAT, IMD, and Toll pathways. At the end, we explained how hormones and nerve system also can impact on immune system and make it more beautiful. In concluding remarks, the possibility of taking help from insect immune system to fight against diseases such as cancer has been considered.

Keywords: insects, innate immunity, melanization, intracellular pathways, hormones

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1246 Phenology and Size in the Social Sweat Bee, Halictus ligatus, in an Urban Environment

Authors: Rachel A. Brant, Grace E. Kenny, Paige A. Muñiz, Gerardo R. Camilo

Abstract:

The social sweat bee, Halictus ligatus, has been documented to alter its phenology as a response to changes in temporal dynamics of resources. Furthermore, H. ligatus exhibits polyethism in natural environments as a consequence of the variation in resources. Yet, we do not know if or how H. ligatus responds to these variations in urban environments. As urban environments become much more widespread, and human population is expected to reach nine billion by 2050, it is crucial to distinguish how resources are allocated by bees in cities. We hypothesize that in urban regions, where floral availability varies with human activity, H. ligatus will exhibit polyethism in order to match the extremely localized spatial variability of resources. We predict that in an urban setting, where resources vary both spatially and temporally, the phenology of H. ligatus will alter in response to these fluctuations. This study was conducted in Saint Louis, Missouri, at fifteen sites each varying in size and management type (community garden, urban farm, prairie restoration). Bees were collected by hand netting from 2013-2016. Results suggest that the largest individuals, mostly gynes, occurred in lower income neighborhood community gardens in May and August. We used a model averaging procedure, based on information theoretical methods, to determine a best model for predicting bee size. Our results suggest that month and locality within the city are the best predictors of bee size. Halictus ligatus was observed to comply with the predictions of polyethism from 2013 to 2015. However, in 2016 there was an almost complete absence of the smallest worker castes. This is a significant deviation from what is expected under polyethism. This could be attributed to shifts in planting decisions, shifts in plant-pollinator matches, or local climatic conditions. Further research is needed to determine if this divergence from polyethism is a new strategy for the social sweat bee as climate continues to alter or a response to human dominated landscapes.

Keywords: polyethism, urban environment, phenology, social sweat bee

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1245 Biotic Potential of Different Densities of Aphid Parasitoids, Diaeretiella rapae (Hymenoptera: Braconidae: Aphidiinae) Feeding on Brevicoryne brassicae

Authors: Muhammad Anjum Aqueel, Muhammad Jaffar Hussain, Abu Bakar Muhammad Raza

Abstract:

Diaeretiella rapae (M’Intosh) attack most of the aphid species. However, it is specialized in feeding on crucifer aphid, Brevicoryne brassicae. Biological potential of parasitoid is its density-dependency due to sharing of limited resources in few cases. The present study was carried out to check the biotic potential of D. rapae at its different densities (1, 2, 4, 8 and 10 pairs) on fixed number of B. brassicae (100 in number) as a host. The present study was performed under laboratory conditions (25 ± 2 ºC temperature and 65-70 % R.H.). Different biological parameters for parasitoid (e.g. percent parasitism, adult emergence, adult longevity and per pair parasitism) were evaluated to check its biotic potential. The present findings showed that maximum parasitism (43.09 % ± 0.63) was observed in highest density (10 pairs) and minimum parasitism (16.59 % ± 1.28) in lowest density (1 pair) of the parasitoid. Maximum adult emergence (80.31 % ± 1.33) was observed in highest density (10 pairs) and minimum parasitism (45.99 % ± 1.27) in lowest density (1 pair) of the parasitoid. In the case of adult longevity, highest (8.2 days ± 0.38) and lowest (6 days ± 0.32) longevity were observed in lowest (1 pair) and highest (10 pairs) densities of parasitoids respectively. However, per pair parasitism rate decreased with the increase in parasitoid densities due to intra-specific competition, developed between the parasitoids for parasitism. The positive but close relationship was observed between percent parasitism and adult emergence. The increase in parasitoid densities increased the percent parasitism and adult emergence of the parasitoid. So, we conclude that an inter-specific competition negatively affected the efficacy of parasitoids and may reduce the fitness of the emerging parasitoid.

Keywords: Diaeretiella rapae, Parasitoid densities, Percent parasitism, adult emergence

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1244 Studies on Knockdown Resistance Mutations in Aedes aegypti and Aedes albopictus in India

Authors: Neera Kapoor

Abstract:

Background: Knockdown Resistance (KDR) is one of the mechanisms of insecticide resistance in insects caused by the reduced target site sensitivity i.e. voltage gated sodium channel (VGSC) rendering it less sensitive to the toxic effects of DDT and pyrethroids. In this study, we evaluated insecticide susceptibility and its underlying KDR mechanism in eight Ae. aegypti and five Ae. albopictus field populations. Methodology: Field population was collected from four different geographical regions of India covering 18 districts of ten states. For genotyping of twelve KDR alleles in Ae. aegypti field populations, three PCR based assays were used; with DNA sequencing; ASPCR; PCR-RFLP. Genomic DNA was isolated, and three partial domains (II, III, and IV) of VGSC were amplified and sequenced. Results: Molecular screening for common KDR mutations, revealed the presence of five mutations viz. S989P, V1016G, T1520I, F1534C/L. Two novel mutations were observed, first at T1520 (ACC) residue where a C > T substitution at the second position of codon results in amino acid change to Isoleucine (ATC). Second mutation was an alternative point mutation at F1534 (TTC) residue where a substitution of T > C at the first position of codon results in an amino acid change to Leucine (CTC). ASPCRs were not accurate, so three PCR-RFLP assays were developed for genotyping of five KDR alleles in Ae. aegypti; viz. T1520I, F1534C/L. Representative samples of all genotypes (n=200) were sequenced to validate the newly developed PCR based assays for Ae. aegypti. Genotyping results showed that 989P is linked to 1016G and novel mutation 1520I was always found with 1534C allele. Conclusion: Present study confirmed the presence of DDT and pyrethroid resistance among Ae. aegypti populations in India and for the first time reported KDR mutations in this species from India including two novel mutations. Results of present study lead us to infer that, at least five KDR mutations (S989P, V1016G, T1530I, F1534C, and F1534L) can be seen as a potential marker for DDT/pyrethroid resistance.

Keywords: F1534C, F1534L, S989P, T1530I, V1016G

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1243 Assessment of Occupational Exposure and Individual Radio-Sensitivity in People Subjected to Ionizing Radiation

Authors: Oksana G. Cherednichenko, Anastasia L. Pilyugina, Sergey N.Lukashenko, Elena G. Gubitskaya

Abstract:

The estimation of accumulated radiation doses in people professionally exposed to ionizing radiation was performed using methods of biological (chromosomal aberrations frequency in lymphocytes) and physical (radionuclides analysis in urine, whole-body radiation meter, individual thermoluminescent dosimeters) dosimetry. A group of 84 "A" category employees after their work in the territory of former Semipalatinsk test site (Kazakhstan) was investigated. The dose rate in some funnels exceeds 40 μSv/h. After radionuclides determination in urine using radiochemical and WBC methods, it was shown that the total effective dose of personnel internal exposure did not exceed 0.2 mSv/year, while an acceptable dose limit for staff is 20 mSv/year. The range of external radiation doses measured with individual thermo-luminescent dosimeters was 0.3-1.406 µSv. The cytogenetic examination showed that chromosomal aberrations frequency in staff was 4.27±0.22%, which is significantly higher than at the people from non-polluting settlement Tausugur (0.87±0.1%) (р ≤ 0.01) and citizens of Almaty (1.6±0.12%) (р≤ 0.01). Chromosomal type aberrations accounted for 2.32±0.16%, 0.27±0.06% of which were dicentrics and centric rings. The cytogenetic analysis of different types group radiosensitivity among «professionals» (age, sex, ethnic group, epidemiological data) revealed no significant differences between the compared values. Using various techniques by frequency of dicentrics and centric rings, the average cumulative radiation dose for group was calculated, and that was 0.084-0.143 Gy. To perform comparative individual dosimetry using physical and biological methods of dose assessment, calibration curves (including own ones) and regression equations based on general frequency of chromosomal aberrations obtained after irradiation of blood samples by gamma-radiation with the dose rate of 0,1 Gy/min were used. Herewith, on the assumption of individual variation of chromosomal aberrations frequency (1–10%), the accumulated dose of radiation varied 0-0.3 Gy. The main problem in the interpretation of individual dosimetry results is reduced to different reaction of the objects to irradiation - radiosensitivity, which dictates the need of quantitative definition of this individual reaction and its consideration in the calculation of the received radiation dose. The entire examined contingent was assigned to a group based on the received dose and detected cytogenetic aberrations. Radiosensitive individuals, at the lowest received dose in a year, showed the highest frequency of chromosomal aberrations (5.72%). In opposite, radioresistant individuals showed the lowest frequency of chromosomal aberrations (2.8%). The cohort correlation according to the criterion of radio-sensitivity in our research was distributed as follows: radio-sensitive (26.2%) — medium radio-sensitivity (57.1%), radioresistant (16.7%). Herewith, the dispersion for radioresistant individuals is 2.3; for the group with medium radio-sensitivity — 3.3; and for radio-sensitive group — 9. These data indicate the highest variation of characteristic (reactions to radiation effect) in the group of radio-sensitive individuals. People with medium radio-sensitivity show significant long-term correlation (0.66; n=48, β ≥ 0.999) between the values of doses defined according to the results of cytogenetic analysis and dose of external radiation obtained with the help of thermoluminescent dosimeters. Mathematical models based on the type of violation of the radiation dose according to the professionals radiosensitivity level were offered.

Keywords: biodosimetry, chromosomal aberrations, ionizing radiation, radiosensitivity

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1242 Insecticide Efficacy against Jassids in Egg Plants

Authors: Zunnu Raen Akhtar, Farhan Ali, Muhammad Saeed-Ur-Rehman

Abstract:

Jassids are considered as serious sucking pests in eggplants. Jassids can be controlled using imidacloprid, but it can also result in non-target ecological impacts on eco-system. It can also result in reduced population of predators of jassids in the field. An experiment was conducted on jassids, Amrasca sp. reared on eggplant leaves were treated with insecticide imidacloprid at lower, recommended and higher doses including 1L, 2L, 3L respectively. 3rd instar larvae and adults of jassids were exposed to lower, recommended, higher doses. Mortality tests were repeated three times for each dose and insect growth stage. Imidacloprid was sprayed on the leaves followed by drying. Data was recorded for 4, 8, 12, 16, 20, 24 hours after spraying insecticide on the leaves. Results showed that higher mortality was observed in higher and recommended doses, while slow mortality was observed in the case of lower dose. It can be asserted that higher and recommended doses causing immediate mortality of insects are better to control Amrasca sp. in the field, it will not cause immediate resistance development in insects against imidacloprid.

Keywords: Amrasca sp., imidacloprid, egg plant, efficacy

Procedia PDF Downloads 226
1241 Brevicoryne brassicae Compatibility with Maize in Multiple Cropping System

Authors: Zunnu Raen Akhtar

Abstract:

Brevicoryne brassicae, aphid feeds on cabbage and Brassica sp. as preferred host. Brassica plants usually ripen when maize starts growing in multiple cropping systems. Experiment was conducted to observe suitability of B. brassicae by rearing it on maize as host. In a tritrophic eco-system, predator coccinellids can be found in the fields of brassica and maize. This experiment emphasized on issue of aphids growing incidence in a cropping system. Brassica is sown and harvested earlier than maize and is attacked by aphids, while maize is also attacked by aphids. Five mortality tests were conducted of B. brassicae fed on maize. Out of five mortality tests, 3 tests were conducted using 1st instar, while in two mortality tests, 2nd instars of aphids were used. Mortality tests revealed that first instar mortality was quite high on the second day, while in second instar larvae mortality was delayed up to third to the fourth day. These experiments reveal that aphids can use maize as substitute host at later instars as compared to young ones. These experiments can be foundation for studying further crop-insect interaction and sampling techniques used for this purpose.

Keywords: host suitability, B. brassicae, maize, tritrophic interaction

Procedia PDF Downloads 194
1240 A Mathematical Analysis of a Model in Capillary Formation: The Roles of Endothelial, Pericyte and Macrophages in the Initiation of Angiogenesis

Authors: Serdal Pamuk, Irem Cay

Abstract:

Our model is based on the theory of reinforced random walks coupled with Michealis-Menten mechanisms which view endothelial cell receptors as the catalysts for transforming both tumor and macrophage derived tumor angiogenesis factor (TAF) into proteolytic enzyme which in turn degrade the basal lamina. The model consists of two main parts. First part has seven differential equations (DE’s) in one space dimension over the capillary, whereas the second part has the same number of DE’s in two space dimensions in the extra cellular matrix (ECM). We connect these two parts via some boundary conditions to move the cells into the ECM in order to initiate capillary formation. But, when does this movement begin? To address this question we estimate the thresholds that activate the transport equations in the capillary. We do this by using steady-state analysis of TAF equation under some assumptions. Once these equations are activated endothelial, pericyte and macrophage cells begin to move into the ECM for the initiation of angiogenesis. We do believe that our results play an important role for the mechanisms of cell migration which are crucial for tumor angiogenesis. Furthermore, we estimate the long time tendency of these three cells, and find that they tend to the transition probability functions as time evolves. We provide our numerical solutions which are in good agreement with our theoretical results.

Keywords: angiogenesis, capillary formation, mathematical analysis, steady-state, transition probability function

Procedia PDF Downloads 156
1239 Using Polymerase Chain Reaction Technique to Observe the Resistant Strains of Pectinophora gossypiella against Cry1Ac Expressing Cotton

Authors: Zunnu Raen Akhtar, U. Irshad, M. Majid

Abstract:

Due to the widespread cultivation of transgenic cotton, intense selection pressure resulted in resistant allele in pink bollworm, Pectinophora gossypiella (Gelechiidae: Lepidoptera). A resistant strain of pink bollworm against transgenic cotton has become a challenge to Integrated Resistance Management (IRM) in the World. Laboratory and field studies were conducted to determine the resistant strains of pink bollworm by performing bioassay, extracting the DNA, conducting PCR of both laboratory as well as field collected pink bollworms to observe the developed resistance. In all of the studies, two Bt varieties FH-142 and FH-118 expressing Cry1Ac compared to non-Bt (Control) were tested against pink bollworm. In the laboratory, bioassay results showed that there was no significant mortality difference between Bt and non-Bt varieties. Similar mortality percentage was observed in transgenic and non-transgenic (control) variety. Insects which were survived after bioassay, as well as those collected from the Bt cotton fields, were selected for further molecular studies. DNA extraction followed by PCR was conducted to check the resistant strains in pink bollworm. In field studies, we also observed the population dynamics of pink boll worms on Bt as compared to non-Bt varieties. Laboratory and field studies confirmed that resistant strains occurs in Pakistani Bt cotton fields. Different strategies should be adopted to combat that serious prevailing resistance issues.

Keywords: transgenic cotton, resistance, pectinophora gossypiella, , integrated resistance management (IRM), polymerase chain reaction (PCR)

Procedia PDF Downloads 236
1238 Alternative Biocides to Reduce Algal Fouling in Seawater Industrial Cooling Towers

Authors: Mohammed Al-Bloushi, Sanghyun Jeong, Torove Leiknes

Abstract:

Biofouling in the open recirculating cooling water systems may cause biological corrosion, which can reduce the performance, increase the energy consummation and lower heat exchange efficiencies of the cooling tower. Seawater cooling towers are prone to biofouling due to the presences of organic and inorganic compounds in the seawater. The availability of organic and inorganic nutrients, along with sunlight and continuous aeration of the cooling tower contributes to an environment that is ideal for microbial growth. Various microorganisms (algae, fungi, and bacteria) can grow in a cooling tower system under certain environmental conditions. The most commonly being used method to control the biofouling in the cooling tower is the addition of biocides such as chlorination. In this study, algae containing diatom and green algae were added to the cooling tower basin, and its viability was monitored in the recirculating cooling seawater loop as well as in the cooling tower basin. Continuous addition of biocides was employed in pilot-scale seawater cooling towers, and it was operated continuously for 2 months. Three different types of oxidizing biocides, namely chlorine, chlorine dioxide and ozone, were tested. The results showed that all biocides were effective in keeping the biological growth to the minimum regardless of algal addition. Amongst the biocides, ozone could reduce 99% of total live cells of bacteria and algae, followed by chlorine dioxide at 97%, while the conventional chlorine showed only 89% reduction in the bioactivities.

Keywords: algae, biocide, biofouling, seawater cooling tower

Procedia PDF Downloads 239
1237 Evaluation of Low Temperature as Treatment Tool for Eradication of Mediterranean Fruit Fly (Ceratitis capitata) in Artificial Diet

Authors: Farhan J. M. Al-Behadili, Vineeta Bilgi, Miyuki Taniguchi, Junxi Li, Wei Xu

Abstract:

Mediterranean fruit fly (Ceratitis capitata) is one of the most destructive pests of fruits and vegetables. Medfly originated from Africa and spread in many countries, and is currently an endemic pest in Western Australia. Medfly has been recorded from over 300 plant species including fruits, vegetables, nuts and its main hosts include blueberries, citrus, stone fruit, pome fruits, peppers, tomatoes, and figs. Global trade of fruits and other farm fresh products are suffering from the damages of this pest, which prompted towards the need to develop more effective ways to control these pests. The available quarantine treatment technologies mainly include chemical treatment (e.g., fumigation) and non-chemical treatments (e.g., cold, heat and irradiation). In recent years, with the loss of several chemicals, it has become even more important to rely on non-chemical postharvest control technologies (i.e., heat, cold and irradiation) to control fruit flies. Cold treatment is one of the most potential trends of focus in postharvest treatment because it is free of chemical residues, mitigates or kills the pest population, increases the strength of the fruits, and prolongs storage time. It can also be applied to fruits after packing and ‘in transit’ during lengthy transport by sea during their exports. However, limited systematic study on cold treatment of Medfly stages in artificial diets was reported, which is critical to provide a scientific basis to compare with previous research in plant products and design an effective cold treatment suitable for exported plant products. The overall purpose of this study was to evaluate and understand Medfly responses to cold treatments. Medfly stages were tested. The long-term goal was to optimize current postharvest treatments and develop more environmentally-friendly, cost-effective, and efficient treatments for controlling Medfly. Cold treatment with different exposure times is studied to evaluate cold eradication treatment of Mediterranean fruit fly (Ceratitis capitata), that reared on carrot diet. Mortality is important aspect was studied in this study. On the other hand, study effects of exposure time on mortality means of medfly stages.

Keywords: cold treatment, fruit fly, Ceratitis capitata, carrot diet, temperature effects

Procedia PDF Downloads 224
1236 Report of the Sea Cucumber Stichopus hermanni from Umm Al-Maradim and Qaruh Islands in Kuwait

Authors: M. Al-Roumi, A. Al-Yaqout, A. Al-Baz

Abstract:

Recently, sea cucumbers have shown to be significant to global trade and incomes due to their high commercial value for the pharmaceutical and cosmetics industry. This rising demand for sea cucumber products has created increasing harvest stress on the natural populations and led to the depletion of sea cucumbers stocks worldwide and accordingly there is a big concern on the marine environment's health worldwide. Few species have been reported and identified via morophlogical features only. Several sea cucumber species were collected from the North West side reefs at Qaruh Island, and the north side of Umm Al-Maradem Island in Kuwait waters, in the north-western Arabian Gulf, in order to identify the sea cucumber species available in the Kuwaiti waters. The identified species were Holothuria atra, Holothuria arenicola, Holothuria hilla and Holothuria impatiens. Species identification was made using morphological keys and review of their ossicles. This paper reports the species Stichopus hermanni from Kuwait.

Keywords: Stichopus hermanni, Kuwait waters, Arabian Gulf, ossicles

Procedia PDF Downloads 194
1235 Using Sea Cucumber for Mitigation of Marine Pollution

Authors: A. Al-Yaqout, A. Al-Alawi, T. Al-Said, E. Al-Enezi, M. Al-Roumi

Abstract:

Kuwait’s marine environment suffers from increased organic pollution. Sea cucumbers play an important role in the marine environment. They create a healthier environment for many types of benthic micro-organisms through their slow movement and feeding mechanism on micro-organisms and organic material. A preliminary study has been conducted in Kuwait Institute for Scientific Research to assess the possibility of using sea cucumbers for mitigation of the coastal pollution. Sediments were collected from locations identified to be heavily loaded with organic pollutants. Ten aquaria glass tanks, 65x 40x 30cm will be supplied with 10 cm height (14 kg) of the sediments added in each tank and filled with 70 L of filtered seawater. Two species were used in this study, Stichopus hermanni, and Holothuria atra. Water and sediment samples were analyzed weekly. The results showed promising possibility for using sea cucumber to lower the organic load in sediments.

Keywords: organic pollution, sea cucumbers, mitigation, Stichopus hermanni, Holothuria atra

Procedia PDF Downloads 314
1234 The Bicoid Gradient in the Drosophila Embryo: 3D Modelling with Realistic Egg Geometries

Authors: Alexander V. Spirov, David M. Holloway, Ekaterina M. Myasnikova

Abstract:

Segmentation of the early Drosophila embryo results from the dynamic establishment of spatial gene expression patterns. Patterning occurs on an embryo geometry which is a 'deformed' prolate ellipsoid, with anteroposterior and dorsal-ventral major and minor axes, respectively. Patterning is largely independent along each axis, but some interaction can be seen in the 'bending' of the segmental expression stripes. This interaction is not well understood. In this report, we investigate how 3D geometrical features of the early embryo affect the segmental expression patterning. Specifically, we study the effect of geometry on formation of the Bicoid primary morphogenetic gradient. Our computational results demonstrate that embryos with a much longer ventral than dorsal surface ('bellied') can produce curved Bicoid concentration contours which could activate curved stripes in the downstream pair-rule segmentation genes. In addition, we show that having an extended source for Bicoid in the anterior of the embryo may be necessary for producing the observed exponential form of the Bicoid gradient along the anteroposterior axis.

Keywords: Drosophila embryo, bicoid morphogenetic gradient, exponential expression profile, expression surface form, segmentation genes, 3D modelling

Procedia PDF Downloads 274
1233 Robustness Conditions for the Establishment of Stationary Patterns of Drosophila Segmentation Gene Expression

Authors: Ekaterina M. Myasnikova, Andrey A. Makashov, Alexander V. Spirov

Abstract:

First manifestation of a segmentation pattern in the early Drosophila development is the formation of expression domains (along with the main embryo axis) of genes belonging to the trunk gene class. Highly variable expression of genes from gap family in early Drosophila embryo is strongly reduced by the start of gastrulation due to the gene cross-regulation. The dynamics of gene expression is described by a gene circuit model for a system of four gap genes. It is shown that for the formation of a steep and stationary border by the model it is necessary that there existed a nucleus (modeling point) in which the gene expression level is constant in time and hence is described by a stationary equation. All the rest genes expressed in this nucleus are in a dynamic equilibrium. The mechanism of border formation associated with the existence of a stationary nucleus is also confirmed by the experiment. An important advantage of this approach is that properties of the system in a stationary nucleus are described by algebraic equations and can be easily handled analytically. Thus we explicitly characterize the cross-regulation properties necessary for the robustness and formulate the conditions providing this effect through the properties of the initial input data. It is shown that our formally derived conditions are satisfied for the previously published model solutions.

Keywords: drosophila, gap genes, reaction-diffusion model, robustness

Procedia PDF Downloads 366
1232 Forests, the Sanctuaries to Specialist and Rare Wild Native Bees at the Foothills of Western Himalayas

Authors: Preeti Virkar, V. P. Uniyal, Vinod Kumar Bhatt

Abstract:

With 50% decline in managed honey bee hives in the continents of Europe and America, farmers and landscape managers are turning to native wild bees for their essential ecosystem services of pollination. Wild bees population are too under danger due to the rapid land use changes from anthropogenic activities. With an escalating population reaching 9.0 billion by 2050, human-induced land use changes are predicted to further deteriorate the habitats of numerous species by the turn of this century. The status of bees are uncertain, especially in the tropical regions of the world, which also questions the crisis of global pollinator decline and their essential services to wild and managed flora. Our investigation collectively compares wild native bee diversity and their status in forests and agroecosystems in Doon Valley landscape, situated at the foothills of Himalayan ranges, Uttarakhand, India. We seek to ask whether (1) natural habitat are refuge to richer and rarer bees communities than the agroecosystems, (2) Are agroecosystems closer to natural habitats similar to them than agroecosystems farther away; hence support richer bee communities and hence, (3) Do polyculture farms support richer bee communities than monoculture. The data was collected using observation and pantrap sampling form February to May, 2012 to 2014. We recorded 43 species of bees in Doon Valley. They belonged to 5 families; Megachilidae, Apidae, Andrenidae, Halictidae and Collitidae. A multinomial model approach was used to classify the bees into 2 habitats, in which forests demonstrated to support greater number of specialist (26%, n= 11) species than agroecosystems (7%, n= 3). The valley had many species categorized as the rare (58%, n= 25) and very few generalists (9%, n=4). A linear regression model run on our data demonstrated higher bee diversity in agro-ecosystems in close proximity to forests (H’ for < 200 m = 1.60) compared to those further away (H’ for > 600 m = 0.56) (R2=0.782, SE=0.148, p value=0.004). Organic agriculture supported significantly greater species richness in comparison to conventional farms (Mann-Whitney U test, n1 = 33, n2 = 35; P = 0.001). Forests ecosystems are refuge to rare specialist groups and support bee communities in nearby agroecosystems. The findings of our investigation demonstrate the importance of natural habitats as a potential refuge for rare native wild bee pollinators. Polyculture in the valley behaves similar to natural habitats and supports diverse bee communities in comparison to conventional monocultures. Our study suggests that the farming communities adopt diverse organic agriculture systems to attract wild pollinators beneficial for better crop production. Forests are sanctuaries for bees to nest, forage, and breed. Therefore, our outcome also suggests landscape managers not only preserve protected areas but also enhance the floral diversity in semi-natural and urban areas.

Keywords: native bees, pollinators, polyculture, agroecosystem, natural habitat, diversity, monoculture, specialists, generalists

Procedia PDF Downloads 217
1231 Use of Fruit Beetles, Waxworms Larvae and Tiger Worms in Waste Conditioning for Composting

Authors: Waleed S. Alwaneen

Abstract:

In many countries, cow dung is used as farm manure and for biogas production. Several bacterial strains associated with cow dung such as Campylobacter, Salmonella sp. and Escherichia coli cause serious human diseases. The objective of the present study was to investigate the use of insect larvae including fruit beetle, waxworms and tiger worms to improve the breakdown of agricultural wastes and reduce their pathogen loads. Fresh cow faeces were collected from a cattle farm and distributed into plastic boxes (100 g/box). Each box was provided with 10 larvae of fruit beetle, Waxworms and Tiger worms, respectively. There were 3 replicates in each treatment including the control. Bacteria were isolated weekly from both control and cow faeces to which larvae were added to determine the bacterial populations. Results revealed that the bacterial load was higher in the cow faeces treated with fruit beetles than in the control, while the bacterial load was lower in the cow faeces treated with waxworms and tiger worms than in the control. The activities of the fruit beetle larvae led to the cow faeces being liquefied which provided a more conducive growing media for bacteria. Therefore, higher bacterial load in the cow faeces treated with fruit beetle might be attributed to the liquefaction of cow faeces.

Keywords: fruit beetle, waxworms, tiger worms, waste conditioning, composting

Procedia PDF Downloads 250
1230 Turing Pattern in the Oregonator Revisited

Authors: Elragig Aiman, Dreiwi Hanan, Townley Stuart, Elmabrook Idriss

Abstract:

In this paper, we reconsider the analysis of the Oregonator model. We highlight an error in this analysis which leads to an incorrect depiction of the parameter region in which diffusion driven instability is possible. We believe that the cause of the oversight is the complexity of stability analyses based on eigenvalues and the dependence on parameters of matrix minors appearing in stability calculations. We regenerate the parameter space where Turing patterns can be seen, and we use the common Lyapunov function (CLF) approach, which is numerically reliable, to further confirm the dependence of the results on diffusion coefficients intensities.

Keywords: diffusion driven instability, common Lyapunov function (CLF), turing pattern, positive-definite matrix

Procedia PDF Downloads 358
1229 Molecular Identification of Camel Tick and Investigation of Its Natural Infection by Rickettsia and Borrelia in Saudi Arabia

Authors: Reem Alajmi, Hind Al Harbi, Tahany Ayaad, Zainab Al Musawi

Abstract:

Hard ticks Hyalomma spp. (family: Ixodidae) are obligate ectoparasite in their all life stages on some domestic animals mainly camels and cattle. Ticks may lead to many economic and public health problems because of their blood feeding behavior. Also, they act as vectors for many bacterial, viral and protozoan agents which may cause serious diseases such as tick-born encephalitis, Rocky-mountain spotted fever, Q-fever and Lyme disease which can affect human and/or animals. In the present study, molecular identification of ticks that attack camels in Riyadh region, Saudi Arabia based on the partial sequence of mitochondrial 16s rRNA gene was applied. Also, the present study aims to detect natural infections of collected camel ticks with Rickessia spp. and Borelia spp. using PCR/hybridization of Citrate synthase encoding gene present in bacterial cells. Hard ticks infesting camels were collected from different camels located in a farm in Riyadh region, Saudi Arabia. Results of the present study showed that the collected specimens belong to two species: Hyalomma dromedari represent 99% of the identified specimens and Hyalomma marginatum which account for 1 % of identified ticks. The molecular identification was made through blasting the obtained sequence of this study with sequences already present and identified in GeneBank. All obtained sequences of H. dromedarii specimens showed 97-100% identity with the same gene sequence of the same species (Accession # L34306.1) which was used as a reference. Meanwhile, no intraspecific variations of H. marginatum mesured because only one specimen was collected. Results also had shown that the intraspecific variability between individuals of H. dromedarii obtained in 92 % of samples ranging from 0.2- 6.6%, while the remaining 7 % of the total samples of H. dromedarii showed about 10.3 % individual differences. However, the interspecific variability between H. dromedarii and H. marginatum was approximately 18.3 %. On the other hand, by using the technique of PCR/hybridization, we could detect natural infection of camel ticks with Rickettsia spp. and Borrelia spp. Results revealed the natural presence of both bacteria in collected ticks. Rickettsial spp. infection present in 29% of collected ticks, while 35% of collected specimen were infected with Borrelia spp. The valuable results obtained from the present study are a new record for the molecular identification of camel ticks in Riyadh, Saudi Arabia and their natural infection with both Rickettsia spp. and Borrelia spp. These results may help scientists to provide a good and direct control strategy of ticks in order to protect one of the most important economic animals which are camels. Also results of this project spotlight on the disease that might be transmitted by ticks to put out a direct protective plan to prevent spreading of these dangerous agents. Further molecular studies are needed to confirm the results of the present study by using other mitochondrial and nuclear genes for tick identification.

Keywords: Camel ticks, Rickessia spp. , Borelia spp. , mitochondrial 16s rRNA gene

Procedia PDF Downloads 277
1228 Effect of Palm Bunch Ash and Neem (Azardirachta indica A. Juss) Leaf Powder on Termite Infestation in Groundnut Field

Authors: K. O. Ogbedeh, C. P. Ekwe, G. O. Ihejirika, S. A. Dialoke, O. P. Onyewuchi, C. P. Anyanwu, I. E. Kalu

Abstract:

As one of the major pests of field crops, termites attack groundnut at all stages of its development, especially during prolonged dry spell. Effect of palm bunch ash and neem(Azardirachta indica A. Juss) leaf powder on termite infestation in groundnut field in Owerri, Nigeria was investigated in this study. The field trial was carried out in 2016 at the Teaching and Research Farm of the Federal University of Technology, Owerri, Nigeria. The experiment was laid out in a 3x3 Factorial fitted into a Randomized Complete Block Design (RCBD) with three replications. The treatments include three rates of palm bunch ash at 0.0 (control), 1.0 and 2.0tons/ha and three rates of neem leaf powder at 0.0(control), 1.0, 2.0 tons/ha respectively. Data were collected on percentage emergence, termite incidence and termite severity. These were subjected to analysis of variance (ANOVA), and means were separated using least significant difference at 5% level of probability. The result shows that there were no significant (P= 0.05) differences in percentage emergence amongst treatment means due to palm bunch ash and neem leaf powder applications. Contrarily, palm bunch ash at 2.0 tons/ha recorded the least termite incidence especially at twelve weeks after planting (12WAP) with a value of 22.20% while control plot maintained highest values at 6WAP (48.70%) and 12WAP (48.30%) respectively. Also palm bunch ash at 2.0tons/ha depressed termite severity more than other treatments especially at 2 and 4 WAP (0.56) respectively. Control plots on the other hand consistently maintained highest termite severity throughout the trial with the highest value at 2 and 12WAP (1.56). Conclusively, palm bunch ash exhibited highest depressive action against termite on groundnut especially at higher application value (2.0tons/ha).

Keywords: groundnut, incidence, neem, palm, severity, termites

Procedia PDF Downloads 230