Terpene Rich Essential Oil of Dracocephalum kotschyi Boiss as Efficient Alternative to Synthetic Chemicals in Management of Callosobruchus maculatus Fabricius

The application of plant-derived essential oils has been revealed to proficiently insect pest control agents, meaningfully decreasing the side-effects caused by chemical insecticides. In the present study, the toxicity of essential oil isolated from Dracocephalum kotschyi has been assessed against cowpea weevil (Callosobruchus maculatus Fabricius) as one of the most damaging and cosmopolitan insect pest of stored beans. The other objective of current study was to identify the chemical composition of D. kotschyi essential oil as one of the medicinal plants endemic to Iran. Bioassays results revealed sound fumigant toxicity of essential oil, in which a concentration of 16.41 μl/l produced up to 50% insect mortality after 72 h. Increases in concentrations of the essential oil and exposure times augmented the insect susceptibility so that the highest mortality (96.25%) was achieved at a highest tested concentration (44.12 μl/l) after 72 h. A concentration of 44.12 μl/l was enough to achieve the 50% mortality of tested insects within 10.761 h. The 24 h-LC50 value of essential oil was 24.947 μl/l which decreased to 17.794 μl/l after 72 h. Gas chromatography-mass spectrometry (GC-MS) analysis of the essential oil exposed terpenes including geranyl acetate, citral, z-citral, methyl geranate, limonene, α-pinene and α-campholenal were the main components. Based on the results of present study, the terpene rich essential oil of D. kotschyi may be  considered as promising alternative to the synthetic chemicals for C. maculatus management. Keywords: Callosobruchus maculatus, chemical profile, essential oil, Dracocephalum kotschyi, toxicity

Modeling of the toxicity of Eucalyptus globulus Labill essential oil against red flour beetle, Tribolium castaneum Herbst

Although the application of synthetic chemicals is the main method in the management of insect pests, their overuse has led to public concerns about environmental pollution, threats to human health, and acute and chronic toxicity on non-target organisms. Plant essential oils have introduced as healthy, available, and effective alternatives to detrimental chemicals in recent years. Further, it is necessary to predict the exact amount of required pesticide to save costs and determine the optimal conditions for achievement to the best outcomes. Accordingly, the toxicity of Eucalyptus globulus Labill essential oil against the adults of a cosmopolitan pest Tribolium castaneum Herbst (red flour beetle) along with its modeling and optimization was assessed using Response Surface Methodology (RSM). The coefficients of the essential oil concentration and time as independent variables are positive, showing their increase results in the augmentation of insect pest mortality. E. globulus essential oil showed prospective concentration-time dependent fumigant toxicity against T. castaneum. A quadratic polynomial equation was achieved for the toxicity of E. globulus essential oil using multiple regression analysis: 7.33413 + 0.20191A + 0.47313B + 4.64054E-003AB + 0.016349B2, in which A and B are the exposure time and essential oil concentration. The accuracy of the introduced model was approved through the analysis of variance. Results of the optimization indicated that 45.50 μl/l of essential oil and 72.00 h-exposure time would be adequate to achieve 92.45% mortality of T. castaneum. According to the results of current study, E. globulus essential oil has high potential in the management of T. castaneum and the Response Surface Methodology (RSM) is a suitable method to the optimization and modelling of this bio-effect

Optimization of the antifungal activity of essential oil isolated from aerial parts of Thymus kotschyanus Boiss & Hohen (Lamiaceae)

Although utilization of synthetic chemicals is inevitable for management of economically detrimental agents, numerous side-effects such as environmental contaminations and effects of non-target organisms associated with them. Plant essential oils with low/without toxicity on mammals and as bio-degradable natural materials have been considered for different pests and fungi management in the recent years. In the present study, the essential oil of Thymus kotschyanus isolated by a Clevenger apparatus and its mycelial growth inhibition was measured against two phytopathogenic fungi Botrytis cinerea and Fusarium graminearum. The best models for predicting of antifungal effects were quadratic models. The essential oil showed a prospective mycelial growth inhibition against both phytopathogenic fungi. Optimization of the antifungal effects indicated that 206.207 ppm of the essential oil caused 50% mycelial growth inhibition of B. cinerea after 89.651 h. This value was 85.600 ppm for F. graminearum within 117.194 h. Results of the present study designated a great potential of T. kotschyanus essential oil for management of pathogenic fungi B. cinerea and F. graminearum.Keywords: Essential oil, mycelial growth inhibition, response surface, Thymus kotschyanu

Interactive Segmentation in Multimodal Medical Imagery Using a Bayesian Transductive Learning Approach

Labeled training data in the medical domain is rare and expensive to obtain. The lack of labeled multimodal medical image data is a major obstacle for devising learning-based interactive segmentation tools. Transductive learning (TL) or semi-supervised learning (SSL) offers a workaround by leveraging unlabeled and labeled data to infer labels for the test set given a small portion of label information. In this paper we propose a novel algorithm for interactive segmentation using transductive learning and inference in conditional mixture nave Bayes models (T-CMNB) with spatial regularization constraints. T-CMNB is an extension of the transductive nave Bayes algorithm [1, 20]. The multimodal Gaussian mixture assumption on the class-conditional likelihood and spatial regularization constraints allow us to explain more complex distributions required for spatial classification in multimodal imagery. To simplify the estimation we reduce the parameter space by assuming nave conditional independence between the feature space and the class label. The nave conditional independence assumption allows efficient inference of marginal and conditional distributions for large scale learning and inference [19]. We evaluate the proposed algorithm on multimodal MRI brain imagery using ROC statistics and provide preliminary results. The algorithm shows promising segmentation performance with a sensitivity and specificity of 90.37% and 99.74% respectively and compares competitively to alternative interactive segmentation schemes

Bayesian transduction and Markov conditional mixtures for spatiotemporal interactive segmentation

In this paper we propose a novel transductive learning machine for spatiotemporal classification casted as an interactive segmentation problem. We present Markov conditional mixtures of naive Bayes models with spatiotemporal regularization constraints in a transductive learning and inference framework. The proposed model extends on previous work to account for non independent and identically distributed (i.i.d.) sequential data by imposing the learning and inference problem w.r.t. time. The multimodal mixture assumption on the class-conditional likelihood for each covariate feature domain in conjunction with spatiotemporal regularization constraints allow us to explain more complex distributions required for classification in multimodal longitudinal brain imagery. We evaluate the proposed algorithm on multimodal temporal MRI brain images using ROC statistics and report preliminary results

Radio Frequency Power Amplifiers Adapted For Low Field Magnetic Resonance Imaging

Magnetic Resonance Imaging (MRI) is a reliable and established minimally invasive imaging technique that can provide diagnostically relevant information about the internal structures of the human body. While the basic design of the new MRI scanners is not much different from when they were first designed a few decades ago, finding new ways to modify these big, power-hungry, expensive and complex systems is becoming more and more essential. One of the ways of removing the restrictions that conventional MRI systems have is making them low field. This leads to lighter, smaller, simpler and less expensive MRI scanners that can potentially become portable. Once they are portable, MRI scanners can have various applications ranging from being used in emergency and operating rooms to being taken to remote areas and even outer space. The Space MRI Lab at the University of Saskatchewan focuses on building prototypes of portable MRIs for monitoring astronaut health by using TRansmit Array Spatial Encoding (TRASE). TRASE is an innovative MRI method that operates without relying on noisy, heavy and complex gradient coils. In TRASE, the spatial encoding happens based on the phase gradients of the transmit radio frequency (RF) magnetic field. TRASE-based MRI scanners have specific requirements. One of those requirements is RF power amplifiers (RFPAs) with high-power RF output, high duty cycle and fast switching times. These characteristics are important for achieving maximal TRASE MRI resolution. However, since no commercially available RFPA with these specifications exists, it was necessary to build RFPAs customized for TRASE applications. A class A/B Ham radio power amplifier design was modified to be more compatible with TRASE-based MRIs. As part of this thesis, two of these RFPAs were constructed at the University of Saskatchewan Space MRI Lab. The RFPAs were assembled to be used with the Merlin MRI, an ankle-sized portable MRI tested in zero-gravity which uses TRASE. Fortunately, both of the RFPAs showed expected results at the testing stage and have since been integrated with the Merlin MRI. Details of the assembly work are presented in this thesis

An intelligent modular real-time vision-based system for environment perception

A significant portion of driving hazards is caused by human error and disregard for local driving regulations; Consequently, an intelligent assistance system can be beneficial. This paper proposes a novel vision-based modular package to ensure drivers' safety by perceiving the environment. Each module is designed based on accuracy and inference time to deliver real-time performance. As a result, the proposed system can be implemented on a wide range of vehicles with minimum hardware requirements. Our modular package comprises four main sections: lane detection, object detection, segmentation, and monocular depth estimation. Each section is accompanied by novel techniques to improve the accuracy of others along with the entire system. Furthermore, a GUI is developed to display perceived information to the driver. In addition to using public datasets, like BDD100K, we have also collected and annotated a local dataset that we utilize to fine-tune and evaluate our system. We show that the accuracy of our system is above 80% in all the sections. Our code and data are available at https://github.com/Pandas-Team/Autonomous-Vehicle-Environment-PerceptionComment: Accepted in NeurIPS 2022 Workshop on Machine Learning for Autonomous Drivin

Hepatoprotective activity of phloretin and hydroxychalcones against Acetaminophen Induced hepatotoxicity in mice

Polyphenolics form a major part of the dietary antioxidant capacity of fruits and vegetables have been identified as chemopreventive or anticancer agents. Hydroxychalcones are polyphenols abundantly distributed throughout the plant kingdom and are compounds with two aromatic rings (benzene or phenol) and an unsaturated side chain. In the present study, effect of phloretin (apple major flavonoid), 4-hydroxychalcone and 4'-hydroxychalcone were investigated against acetaminophen-induced acute liver damage. The study was designed as multiple dose pre- and post-treatments. Mice were administratedacetaminophen (1g/kg and 640 mg/kg for mortality and acute toxicity experiments, respectively). Mortality rate, serum transaminases (SGOT and SGPT) and histological examination were applied. Acetaminophen produced 100% mortality at the dose of 1 g/kg in mice, while pre-treatment and post-treatment (i.p., twice daily for 48 hrs) of animals with phloretin and 4-hydroxychalcone (50 mg/kg) and 4'-hydroxychalcone (25 mg/kg) significantly reduced the mortality rate. Acetaminophen produced acute toxicity at the dose of 640 mg/kg in mice, while pre- and post-treatments of animals with phloretin and hydroxychalcones significantly lowered the rise in SGOT and SGPT. Liver sections collected for histological examination showed cellular changes including centrilobular necrosis, extensive portal inflammation, and micro and macro vesicular structures in the acetaminophen group. These cellular changes were reduced following treatment of mice with Phloretin and hydroxychalcones. Taken collectively, from the results of this study it may be suggested that phloretin and hydroxychalcones have hepatoprotective activity against acetaminophen liver injury in mice

Modeling of the Toxicity of Eucalyptus globulus Labill Essential Oil against Red Flour Beetle, Tribolium castaneum Herbst

Although the application of synthetic chemicals is the main method in the management of insect pests, their overuse has led to public concerns about environmental pollution, threats to human health, and acute and chronic toxicity on non-target organisms. Plant essential oils have introduced as healthy, available, and effective alternatives to detrimental chemicals in recent years. Further, it is necessary to predict the exact amount of required pesticide to save costs and determine the optimal conditions for achievement to the best outcomes. Accordingly, the toxicity of Eucalyptus globulus Labill essential oil against the adults of a cosmopolitan pest Tribolium castaneum Herbst (red flour beetle) along with its modeling and optimization was assessed using Response Surface Methodology (RSM). The coefficients of the essential oil concentration and time as independent variables are positive, showing their increase results in the augmentation of insect pest mortality. E. globulus essential oil showed prospective concentration-time dependent fumigant toxicity against T. castaneum. A quadratic polynomial equation was achieved for the toxicity of E. globulus essential oil using multiple regression analysis: 7.33413 + 0.20191A + 0.47313B + 4.64054E-003AB + 0.016349B2, in which A and B are the exposure time and essential oil concentration. The accuracy of the introduced model was approved through the analysis of variance. Results of the optimization indicated that 45.50 \u3bcl/l of essential oil and 72.00 h-exposure time would be adequate to achieve 92.45% mortality of T. castaneum. According to the results of current study, E. globulus essential oil has high potential in the management of T. castaneum and the Response Surface Methodology (RSM) is a suitable method to the optimization and modelling of this bio-effect

Some Physiological Effects of Nanofertilizers on Wheat-Aphid Interactions

The increasing use of nanofertilizers in modern agriculture and their impact on crop yield and pest management require further research. In this study, the effects of nano-Fe, -Zn, and -Cu (which are synthesized based on nanochelating technology), and urea (N) fertilizers on the antioxidant activities of wheat plants (cv. Chamran), and the wheat green aphid Schizaphis graminum (Rondani) are investigated. The authors observed the highest levels of phenolics in non-infested nano-Zn-treated plants (26% higher compared with control). The highest H2O2 levels are in the infested and non-infested nano-Zn-treated and infested nano-Fe-treated plants (in infested nano-Zn and nano-Fe treated plants, 18% and non-infested nano-Zn-treated plants, 28% higher compared with control). The highest peroxidase (POX) activity is observed in the infested and non-infested N-treated and non-infested water-treated plants (almost 14%, 37%, and 46% higher than control, respectively). The lowest activity is in the infested plants’ nano-Zn and -Fe treatments (almost 7 and 5 folds lower compared to the control, respectively). The highest and lowest catalase (CAT) activity are in the infested N-treated plants (almost 42% higher than control) and water-treated plants, respectively. The infested nano-Zn, -Fe, -Cu and Hoagland-treated plants showed the highest superoxide dismutase (SOD) activity. Regarding the antioxidant enzyme activities of S. graminum, the highest POX activity is in the nano-Cu treatment (more than two folds higher compared with control); the highest CAT and SOD activities are in the nano-Cu and -Zn treatments. It can be concluded that the application of nanofertilizers caused increasing effects on the wheat plant’s antioxidant system and its resistance to S. graminum