1,681 research outputs found

    Efficient Refuge policies for Bt cotton in India

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    This study examined the efficient refuge policies for Bt cotton for three cotton growing regions in India. This was accomplished by developing a single-pest, dual-toxin biological model simulating bollworm resistance to the Bt toxin and synthetic pyrethroids, followed by formulating profit functions for Bt and non-Bt cotton for a representative producer in each region. Profits received in subsequent periods were considered in the regulatory model in order to choose a refuge constraint (static problem) or a sequence of refuge policies (dynamic problem) for each region that maximize discounted profits received over 15 years, subject to various economic and biological constraints. Dynamic solutions for the regulatory problem were derived for each region using the Bellman equation. Results suggested that South Indian farmers do not need to grow a refuge, but farmers in the North and Central regions do. Results also suggested that planting sprayed refugia might be more profitable than planting unsprayed refugia. Sensitivity analysis revealed that the refuge requirements were sensitive to the initial Bt resistance level, relative proportion of CBWs in natural refuges, and proportions of heterozygous and homozygous fitnesses in all of the three regions. Moreover, static refugia were found more profitable as compared to dynamic refugia in the North and Central regions.Food Security and Poverty,

    Development of concurrent infection of notoedric mange in rabbits infected with Trypanosoma evansi

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    This report describes observations on the development of cutaneous lesions in rabbits experimentally infected with Trypanosoma evansi. Skinscrapings revealed the presence of different developmental stages of Notoedres cati var. cuniculi and the animals were successfully treated by combined anti-Trypanosoma (diminazene aceturate @ 3.5 mg.kg-1body weight) and acaricid treatments (doramectin @ 400mg.kg-1body weight). T. evansi infection probably made the rabbits more prone to infection of notoedric mange and doramectin proved to be effective, practical and well tolerated means of treatment

    From {Solution Synthesis} to {Student Attempt Synthesis} for Block-Based Visual Programming Tasks

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    Block-based visual programming environments are increasingly used to introduce computing concepts to beginners. Given that programming tasks are open-ended and conceptual, novice students often struggle when learning in these environments. AI-driven programming tutors hold great promise in automatically assisting struggling students, and need several components to realize this potential. We investigate the crucial component of student modeling, in particular, the ability to automatically infer students' misconceptions for predicting (synthesizing) their behavior. We introduce a novel benchmark, StudentSyn, centered around the following challenge: For a given student, synthesize the student's attempt on a new target task after observing the student's attempt on a fixed reference task. This challenge is akin to that of program synthesis; however, instead of synthesizing a {solution} (i.e., program an expert would write), the goal here is to synthesize a {student attempt} (i.e., program that a given student would write). We first show that human experts (TutorSS) can achieve high performance on the benchmark, whereas simple baselines perform poorly. Then, we develop two neuro/symbolic techniques (NeurSS and SymSS) in a quest to close this gap with TutorSS

    Reproductive inhibition with gossypol in the lesser bandicoot rat, Bandicota bengalensis

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    Different concentrations of pure gossypol (PG), cottonseed extract containing 8.3% gossypol (CSE) and crude cotton seed oil containing 0.01% gossypol (CCSO) were fed to Bandicota bengalensis of both sexes to determine their effects on reproduction. Single oral administration of either 40 or 80mg PG/kg body weight (bw), or 100 or 200 mg CSE/kg bw did not affect reproductive parameters. Feeding of bait containing 0.05% PG for 4 days; 0.01 or 0.02% PG for 16 days and 0.2 or 0.5% CSE for 7 or 15 days each caused dose dependent decreases in weights of reproductive organs and accessory sex glands and motility, viability and density of sperm in cauda epididymal fluid. There was a dose dependent increase in sperm abnormalities. Gossypol-specific sperm abnormalities were also observed. No breeding was observed in untreated cyclic female rats paired with male rats treated with 0.05 or 0.02% PG for 4 or 16 days respectively, or 0.5% CSE for 15 days. A significant (p ≤ 0.05) increase in oestrous cycle length was observed in female rats fed bait containing 0.01% PG for 18 days or 0.5% CSE for 15 days. No effect on the oestrous cycle was observed in female rats fed bait containing 5 or 10% CCSO for 13 days. Feeding of bait containing 10% CCSO for 15 or 30 days to male rats also had no significant effect on reproductive parameters. Treatment of farmer’s sugarcane fields with 2% zinc phosphide followed by treatment with 10% CCSO for 15 or 30 days had no significant effect on rodent activity. Our results reveal that reproduction of B. bengalensis can be inhibited with multiple doses of gossypol but the effects are dose and time dependent

    Improved Parallel Rabin-Karp Algorithm Using Compute Unified Device Architecture

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    String matching algorithms are among one of the most widely used algorithms in computer science. Traditional string matching algorithms efficiency of underlaying string matching algorithm will greatly increase the efficiency of any application. In recent years, Graphics processing units are emerged as highly parallel processor. They out perform best of the central processing units in scientific computation power. By combining recent advancement in graphics processing units with string matching algorithms will allows to speed up process of string matching. In this paper we proposed modified parallel version of Rabin-Karp algorithm using graphics processing unit. Based on that, result of CPU as well as parallel GPU implementations are compared for evaluating effect of varying number of threads, cores, file size as well as pattern size.Comment: Information and Communication Technology for Intelligent Systems (ICTIS 2017

    Sharing Secret Colour Images with Embedded Visual Cryptography Using the Stamping Algorithm and OTP Procedure

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    Finding a way to ensure the safety of media is becoming increasingly common in the modern world as digital media usage increases. Visual cryptography (VC) offers an efficient method for sending images securely. Images that have been protected using visual encryption can be decoded using features of human vision. Emails are not a highly safe method of exchanging private data because someone else can quickly weaken the content. In the visual cryptography technique, we presented for colour pictures, the divided shares are enclosed in additional pictures using stamping. Using a random number generator, the shares are created. Visual cryptography schemes (VCS) are a method of encoding pictures that conceals the secret information which is present in images. A secret image is encrypted using a straightforward visual cryptography technique by splitting it into n shares, and the stamping operation is carried out by overlapping k shares. It can be beneficial for hiding a secret image. There is a chance that employing cryptography for information exchange could cause security problems because the process of decryption of simple visual cryptographic algorithms can be completed by the human eye. To address this issue, we are using the OTP procedure. In the past, static ID and passwords were employed, making them susceptible to replay and eavesdropping attacks. One Time Password technology, which generates a unique password each time, is utilized to solve this issue. The suggested approach strengthens the security of the created transparencies by applying an envelope to each share and employing a stamping technique to address security vulnerabilities that the previous methods had, such as pixel expansion and noise

    An Overview of Machine Teaching

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    In this paper we try to organize machine teaching as a coherent set of ideas. Each idea is presented as varying along a dimension. The collection of dimensions then form the problem space of machine teaching, such that existing teaching problems can be characterized in this space. We hope this organization allows us to gain deeper understanding of individual teaching problems, discover connections among them, and identify gaps in the field.Comment: A tutorial document grown out of NIPS 2017 Workshop on Teaching Machines, Robots, and Human
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