2,931 research outputs found
Forager bees (Apis mellifera) highly express immune and detoxification genes in tissues associated with nectar processing.
Pollinators, including honey bees, routinely encounter potentially harmful microorganisms and phytochemicals during foraging. However, the mechanisms by which honey bees manage these potential threats are poorly understood. In this study, we examine the expression of antimicrobial, immune and detoxification genes in Apis mellifera and compare between forager and nurse bees using tissue-specific RNA-seq and qPCR. Our analysis revealed extensive tissue-specific expression of antimicrobial, immune signaling, and detoxification genes. Variation in gene expression between worker stages was pronounced in the mandibular and hypopharyngeal gland (HPG), where foragers were enriched in transcripts that encode antimicrobial peptides (AMPs) and immune response. Additionally, forager HPGs and mandibular glands were enriched in transcripts encoding detoxification enzymes, including some associated with xenobiotic metabolism. Using qPCR on an independent dataset, we verified differential expression of three AMP and three P450 genes between foragers and nurses. High expression of AMP genes in nectar-processing tissues suggests that these peptides may contribute to antimicrobial properties of honey or to honey bee defense against environmentally-acquired microorganisms. Together, these results suggest that worker role and tissue-specific expression of AMPs, and immune and detoxification enzymes may contribute to defense against microorganisms and xenobiotic compounds acquired while foraging
Synthesis of Manufacturing Systems Using Co-Platforming
Modern manufacturing environment is characterized by frequent changes within product design in order to satisfy evolving customer requirements. Various strategies are implemented in order to efficiently manage the consequences arising from the product design changes starting from design of the product, planning, manufacturing…etc. This dissertation focuses mainly on the manufacturing phase in which a new concept in manufacturing system synthesis is proposed. A new concept in manufacturing system synthesis has been introduced and coined as “Co-platforming”. Co-platforming is the synthesis of manufacturing systems through mapping product platform features and components to platform machines on one side, and non-platform product features and components to non-platform machines on the other side, in order to reduce the manufacturing system investment cost and prolong the manufacturing system useful life as product variants evolve and change. Tools and methods are developed to synthesize the manufacturing system based on Co-platforming within functional and physical levels. At the functional level, the group of platform and non-platform machines and the number of each machine type are determined. A new matrix based mapping model is proposed to determine the platform and non-platform machines candidates. A ranking coefficient is formulated which ranks the platform machines according to their machining capabilities in order to assist manufacturing firms in decision making concerning which type of platform machine to choose. Furthermore, a new mathematical programming optimization model is proposed in order to provide the optimum selection of machine types among machine candidates and their numbers. Moreover, a new mathematical programming model is proposed which synthesizes manufacturing systems taking into consideration machine level and system level changes based on co-platforming. At the physical level, the manufacturing system configuration is determined which is concerned with determining the number of stages, types of machines in each stage and the number of machines in each stage. A new mathematical programming optimization model is proposed which determines, in addition to the type and number of each machine, the optimal manufacturing system configuration based on co-platforming. The Co-platforming methodology is being applied in two case studies from automotive industry. The first case study is concerned with machining of automotive cylinder blocks taken from Mitsubishi Heavy Industries and the second case study is concerned with the assembly of automotive cylinder heads taken from ABB flexible automation. The results obtained from the co-platforming methodology indicate that cost reduction can be achieved when synthesizing the manufacturing system based on co-platforming
New Triterpene from Conyza aegyptiaca L
From the large genus Conyza (tribe Astereae, family Compositae) about 10% of the approximately 2000 species in this tribe have been subjected to chemical scruting. However, work has been confined largely to root constituents. Among these, polyacetylenes, polyenes and related substances and, in certain groups, coumarins are very characteristic. Less widely distributed, perhaps because they are less intensively searched for, are diterpenoids, so far largely of the labdane and clerodane type
On the controllability of Hilfer-Katugampola fractional differential equations
By employing Kuratowski's measure of noncompactness together with Sadovskii's fixed point theorem, sufficient conditions for controllability results of Hilfer-Katugampola fractional differential equations in Banach spaces are derived
Factors Influencing Intention To Consume Herbal Supplement
The recent growth of herbal industry in Malaysia intensifies the challenges among market players. The main ingredient to be successful in the competitive industry is to be customer-oriented and market-driven. This research aims to contribute to the general understanding of consumer behavioral intention towards choice preferences, and to assist marketers in determining factors that influence consumers’ intention towards herbal supplement
Improving visual SLAM accuracy through deliberate camera oscillations
Visual Simultaneous Localization And Mapping, (VSLAM) algorithms exploit the observation of scene naturally-existing distinct features to infer the camera motion and build a map of a static environment. There is an increasing interest towards building efficient VSLAM algorithms mainly from computational perspectives; however, there may be insufficient clues to solve for SLAM parameters efficiently. In this paper, deliberate camera oscillations are superimposed on the camera main motion (robot motion), mostly in a lateral direction to give sufficient physical clues for the solution. Filtering methods exploit correlation to infer the motion parameters, and since oscillation introduces more local changes, it can enhance the estimation by correlation. Simulation results are presented showing the effects of oscillation parameters on visual SLAM performance in different motion scenarios. The results showed significant improvement of accuracy for oscillating camera over the steady camera case, and in several cases errors are reduced to less than half its value. These simulation results can be the basis to design a real experimental system
Assessment of Insulin Stability Inside Diblock Copolymer PEG-PLA Microspheres
Insulin-loaded PEG2-PLA40 and PEG5-PLA20 microspheres containing 5% bovine insulin were manufactured using single emulsion and w/o/w multiple emulsion-solvent evaporation techniques. Microspheres were characterized for their insulin encapsulation efficiency and release characteristics in phosphate-buffered saline (PBS) at pH 7.4 and 37 °C. Moreover, the stability of the peptide during 18 days of release was evaluated using HPLC and HPLC-MS techniques. The results showed that the loading efficiencies were higher in case of insulin loaded PEG2-PLA40 and PEG5-PLA20 microspheres prepared by single emulsion emulsion-solvent evaporation technique. Insulin release was characterized by an initial burst, which was attributed to the amount of protein located on or close to the microsphere surface. The total ion chromatogram (TIC) of insulin samples extracted after 6, 12 and 18 days of PEG2-PLA40 microspheres erosion showed that insulin was intact inside the eroding microspheres. In addition, only small amounts of protein undergo degradation under these conditions (only 11.69% ± 1.13 of the initially loaded insulin loading were detected as degradation products after 18 days. Mass spectra recorded at these retention times confirmed the presence of insulin with a molar mass of 5734 Da and other two products of molar masses of 5587 Da and 5487 Da
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