334 research outputs found
Ascaroside Expression in Caenorhabditis elegans Is Strongly Dependent on Diet and Developmental Stage
Background:
The ascarosides form a family of small molecules that have been isolated from cultures of the nematode Caenorhabditis elegans. They are often referred to as “dauer pheromones” because most of them induce formation of long-lived and highly stress resistant dauer larvae. More recent studies have shown that ascarosides serve additional functions as social signals and mating pheromones. Thus, ascarosides have multiple functions. Until now, it has been generally assumed that ascarosides are constitutively expressed during nematode development.
Methodology/Principal Findings:
Cultures of C. elegans were developmentally synchronized on controlled diets. Ascarosides released into the media, as well as stored internally, were quantified by LC/MS. We found that ascaroside biosynthesis and release were strongly dependent on developmental stage and diet. The male attracting pheromone was verified to be a blend of at least four ascarosides, and peak production of the two most potent mating pheromone components, ascr#3 and asc#8 immediately preceded or coincided with the temporal window for mating. The concentration of ascr#2 increased under starvation conditions and peaked during dauer formation, strongly supporting ascr#2 as the main population density signal (dauer pheromone). After dauer formation, ascaroside production largely ceased and dauer larvae did not release any ascarosides. These findings show that both total ascaroside production and the relative proportions of individual ascarosides strongly correlate with these compounds' stage-specific biological functions.
Conclusions/Significance:
Ascaroside expression changes with development and environmental conditions. This is consistent with multiple functions of these signaling molecules. Knowledge of such differential regulation will make it possible to associate ascaroside production to gene expression profiles (transcript, protein or enzyme activity) and help to determine genetic pathways that control ascaroside biosynthesis. In conjunction with findings from previous studies, our results show that the pheromone system of C. elegans mimics that of insects in many ways, suggesting that pheromone signaling in C. elegans may exhibit functional homology also at the sensory level. In addition, our results provide a strong foundation for future behavioral modeling studies
An Eulerian–Eulerian formulation for erosion modelling: an alternate approach.
Sand is commonly produced besides petroleum fluids and it presents a major erosional hazard leading to pipe failures. Particle erosion is a complex process in which material is removed due to the repeated particle impacts. Conventionally, a CFD flow solver and computationally intensive lagrangian particle tracking sub–routines, known as Eulerian–Lagrangian (E–L) model, along with empirical erosion equations are used to predict the erosion rates. The present work introduces an Eulerian–Eulerian (E–E) approach in which the multiphase granular model resolves the solid phase and obviates the need of particles tracking. Particle–laden turbulent flow across a flow restrictor, based on an experimental study, is chosen for validation. Numerical experiments are done in Simcenter STAR–CCM+. Comparison with the experimental data demonstrate a good agreement and in particular, the E–E model yields reliable predictions of impact wear locations, erosion rates as those of E–L model. A 90° square bend is also simulated and comparison of erosion rates on the concave wall demonstrate that E–E model can be used as an alternate to computationally expensive approaches
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Impact of Red Gram (Cajanus cajan L) Production Technologies Advised by the KVK Jammikunta in Karimnagar District of Telangana State, India
The study conducted at KVK Jammikunta of Telangana State along with its 15 adopted villages was selected for the study. A sample of 60 Red gram growing farmers who are adopting the KVK technologies and 30 Red gram farmers who are not covered under KVK production technologies were selected from the adopted villages. Present paper highlights the impact of Red gram production technologies in terms of adoption quotient, productivity and profitability in Karimnagar district of Telangana State. High impact in terms of adoption quotient, productivity and profitability of red gram production technologies is observed among the KVK Jammikunta adopted farmers compared to the non adopted farmers
On-Chip Structure for Timing Uncertainity Measurement Induced by Noise in Integrated Circuits
Noise such as voltage drop and temperature in integrated circuits can cause significant performance variation and even functional failure in lower technology nodes. In this paper, we propose an on-chip structure that measures the timing uncertainty induced by noise during functional and test operations. The proposed on-chip structure facilitates the speed characterization under various workloads and test conditions. The basic structure is highly scalable and can be tailored for various applications such as silicon validation, monitoring operation condition and validating logic built-in-self-test conditions. Simulation results show that it offers very high measurement resolution in a highly efficient manner
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Impact of Paddy (Oryza sativa L) Production Technologies Advised by the KVK Jammikunta in Karimnagar District of Telangana State, India
The present paper highlights the impact of paddy production technologies in terms of adoption quotient, productivity and profitability in Karimnagar district of Telangana State (Formerly Andhra Pradesh). High impact in terms of adoption quotient, productivity and profitability of paddy production technologies is observed among the KVK Jammikunta adopted farmers compared to the non adopted farmers
EFFECT OF INTEGRATED CROP MANAGEMENT PRACTICES ON YIELD AND ECONOMICS OF WATERMELON (Citrullus lanatus L.) IN KHAMMAM DISTRICT OF TELANGANA
The present investigation was conducted in different villages under Krishi Vigyan Kendra, Wyra, Khammam operational areas during 2016-17 to 2018-19. Total 30 front line demonstrations were laid out on farmers’ fields in the district. The result of present study revealed that average highest yield 41.5 t/ha was noted in demonstration plot over control (28.5 t/ha) and 43.31 percent of average yield increase was recorded over control plot. Fruit cracking percentage was high in control plot (20.26%) over demonstration plot i.e 10.06 percent. The extension gap ranged from 12.5 t/ha to 13.5 t/ha and technology gap ranged between 5 to 11.5 t/ha respectively, with the technology index of 17 percent during the demonstration years. Besides this, the demonstrated plots gave higher gross returns, net returns with higher benefit cost ratio when compared to farmer’s practice. In present study efforts were also made to study the impact of FLD on horizontal spread which has increased by 105 %, if appropriate package and practices were followed. Further, the study was undertaken to do a formative and summative (outcome and impact) evaluation of the frontline demonstration on integrated crop management in watermelon
Adaptive neuro-fuzzy inference system based evolving fault locator for double circuit transmission lines
Evolving faults are starting in one phase of circuit and spreading to other phases after some time. There has not been a suitable method for locating evolving faults in double circuit transmission line until now. In this paper, a novel method for locating different types of evolving faults occurring in double circuit transmission line is proposed by considering adaptive neuro-fuzzy inference system. The fundamental current and voltage magnitudes are specified as inputs to the proposed method. The simulation results using MATLAB verify the effectiveness and correctness of the protection method. Simulation results show the robustness of the method against different fault locations, resistances, time intervals, and all evolving fault types. Moreover, the proposed method yields satisfactory performance against percentage errors and fault location line parameters. The proposed method is easy to implement and cost-effective for new and existing double circuit transmission line installatio
PLY WISE FAILURE ANALYSIS OF MONO LEAF SPRING USING HYBRID C-GFRP COMPOSITES
Composite materials are a better alternative for Leaf spring material in automobiles since they have higher stiffness, high impact energy absorption, lesser stresses and also higher strength to weight ratio. The objective is to study the ply wise failure criteria in the composite leaf springs. Leaf springs are modeled and analyzed using ACP PrePost and studied for failure criteria based on four failure theories which are: maximum stress failure theory, maximum strain failure theory, Tsai-Hill failure theory and Tsai-Wu failure theory. Failure load based on these theories is calculated by conducting a parametric study. To improve the maximum failure load, hybrid composites are designed and analyzed by replacing the top, bottom and center layers of the composite laminate. The four different cross-sections which are analyzed are Eglass/epoxy, HC1, HC2 and HC3. The study shows that replacing the top, bottom and center layers does improve the maximum failure load. Although this introduces higher stresses in the component, the stresses in the Eglass/epoxy material at the same positions from the center of the laminate are reduced. HC3 shows 30.7% increment in failure load by considering only vertical loads and 20.8% increment in failure load by considering vertical, side loads and twist moment simultaneously. There is an agreeable error of 1.44 – 1.65% in the results obtained for deformation and 0.88 – 1.33% for failure load between simulation and theoretical calculations. Mechanical properties of the Eglass/epoxy material are evaluated by conducting tensile test and three-point bending test. Mono leaf spring similar to the dimensions of Maruthi 800 vehicle is made using hand layup method. The load vs deformation results of leaf spring show a good agreement between the experimental and the simulation values
Analgesic activity of Cissus quadrangularis linn with Zingiber officinale rosc in male wistar rats
Background: The global scenario, human beings are using various forms of treatment for relief of pain; among them, medicinal plant products have gained popularity because of its wide range of use and less side effects.Methods: Adult Albino rats of either sex were selected and divided into 5 groups. The Eddy’s hot plate was used and maintained temperature (55±0.5ºC), the animals were placed on the hot plate and the time taken for paw licking or jumping was recorded and considered as nociceptive response. The reaction time was observed on 0, 30, 60, and 90 minute.Results: The hot plate reaction time in sec was collected in the intervals of 0, 30, 60 and 90 minutes in all groups. Reaction times as follows: group III (Cissus quadrangularis Linn.) were 2.18±0.04, 3.13±0.05**, 5.83±0.05**, 5.39±0.04**; Group IV (Zingiber officinale Rosc.) were 2.12±0.03, 4.13±0.04**, 7.43±0.07**, 7.16±0.06**; Group V Cissus quadrangularis Linn+ Zingiber officinale Rosc.) were 2.21±0.75, 4.67±0.98**, 8.15±0.89**, 9.02±0.75**; Group II (Dexamethasone) were 2.14±0.05, 5.53±0.05**, 8.14±0.06**, 10.08±0.10** respectively, Results are presented as mean±SEM, (n=6), *p<0.01, **p<0.05 dunnet test used as compared to control.Conclusions: Present study reveals that, the combination treatment of Zingiber officinale Rosc. + Cissus quadrangularis Linn. has been shown significant analgesic effect. High analgesic effect was observed with combination therapy; the effect was shown same as standard drug dexamethasone
10-[2-(Dimethylamino)ethyl]-9-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydroacridine-1,8(2H,5H)-dione
In the title compound, C28H38N2O3, the central ring of the acridinedione system adopts a boat conformation, while one of the outer rings adopts a half-chair conformation and the conformation of the other outer ring is between a sofa and a half-chair. The acridinedione system is buckled, with an angle of 22.01 (3)°. The crystal packing comprises layers of molecules laid parallel to the ac plane, being reinforced by an intermolecular C—H⋯O interaction
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