780 research outputs found

    Spawning Induction in the Carp: Past Experience and Future Prospects - A Review

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    Most fish in aquaculture either fail to breed in captivity or their spawning occurs sporadically and late in the season. This is mainly due to the lack of natural cues in captivity, which leads to dysfunction of the endocrine axis regulating oocyte maturation and ovulation. Hypophysation as a remedy for this situation in fish has been employed in aquaculture since the 1930s and is still widely practiced. However, using crude pituitary homogenates in local hatcheries has frequently ended in failures that were attributed to the incon- sistent potency of the injected material and the unknown ovarian stage of the recipient fish. Since the mid 1980s, hypophysation has improved through the introduction of a standardized dry carp pituitary extract in which the luteinizing hormone (LH) content and activity have been calibrated (cal- ibrated carp pituitary extract = CCPE). Induction of spawning, however, is successful mainly in female cohorts in which 65% or more of the oocytes in an ovarian biopsy have migrating germinal vesicles. Further, due to decreasing quantities of industry-processed common carp and the expan- sion of ornamental carp production (koi and goldfish), the growing demand for CCPE could not be met, and an alternative had to be found. A hypo- thalamic approach, introduced into Israeli aquaculture in 1993 (called Dagin), combines a superactive analog of sGnRH (10 Οg/kg), with the water-soluble dopamine (D2) receptor antagonist, metoclopramide (20 mg/kg). The progress of oocyte maturation in ovarian biopsies has been studied in parallel with changes in levels of LH, estradiol, and the matura- tion-inducing steroid (MIS; 17ι, 20β, dihydroxy-4-pregnene-3-one). The hormone profile indicated that the gradual increases in LH and MIS follow- ing a single administration of Dagin were similar to those in fish treated with priming and resolving doses of CCPE. This would explain why Dagin is effective even when only a single injection is given, saving labor and reduc- ing handling stress. CCPE and Dagin were tested in parallel on common carp in a commercial hatchery. The spawning ratio and embryo viability were similar, although the latency between injection and ovulation was con- siderably longer and more variable in Dagin-treated than in CCPE-treated carp. It is recommended to use CCPE at the beginning and end of the spawning season when the LH content in the pituitary is low, and Dagin in mid-season and in field spawning. Future prospects raise the possibility that by employing molecular tools, a recombinant carp LH will be produced that will have the regular and expected potency of the hypophyseal approach without the risk of spreading pathogens from donor fish to broodstock. Work along this line is currently in progress

    Human Evaluation of Text-to-Image Models on a Multi-Task Benchmark

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    We provide a new multi-task benchmark for evaluating text-to-image models. We perform a human evaluation comparing the most common open-source (Stable Diffusion) and commercial (DALL-E 2) models. Twenty computer science AI graduate students evaluated the two models, on three tasks, at three difficulty levels, across ten prompts each, providing 3,600 ratings. Text-to-image generation has seen rapid progress to the point that many recent models have demonstrated their ability to create realistic high-resolution images for various prompts. However, current text-to-image methods and the broader body of research in vision-language understanding still struggle with intricate text prompts that contain many objects with multiple attributes and relationships. We introduce a new text-to-image benchmark that contains a suite of thirty-two tasks over multiple applications that capture a model's ability to handle different features of a text prompt. For example, asking a model to generate a varying number of the same object to measure its ability to count or providing a text prompt with several objects that each have a different attribute to identify its ability to match objects and attributes correctly. Rather than subjectively evaluating text-to-image results on a set of prompts, our new multi-task benchmark consists of challenge tasks at three difficulty levels (easy, medium, and hard) and human ratings for each generated image.Comment: NeurIPS 2022 Workshop on Human Evaluation of Generative Models (HEGM

    Design and Construction of Multigenic Constructs for Plant Biotechnology Using the GoldenBraid Cloning Strategy

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    GoldenBraid (GB) is an iterative and standardized DNA assembling system specially designed for Multigene Engineering in Plant Synthetic Biology. GB is based on restriction–ligation reactions using type IIS restriction enzymes. GB comprises a collection of standard DNA pieces named “GB parts” and a set of destination plasmids (pDGBs) that incorporate the multipartite assembly of standardized DNA parts. GB reactions are extremely efficient: two transcriptional units (TUs) can be assembled from several basic GBparts in one T-DNA less than 24 h. Moreover, larger assemblies comprising 4–5 TUs are routinely built in less than 2 working weeks. Here we provide a detailed view of the GB methodology. As a practical example, a Bimolecular Fluorescence Complementation construct comprising four TUs in a 12 kb DNA fragment is presented.Sarrion-Perdigones, A.; Palací, J.; Granell Richart, A.; Orzáez Calatayud, DV. (2014). Design and Construction of Multigenic Constructs for Plant Biotechnology Using the GoldenBraid Cloning Strategy. Methods in Molecular Biology. 1116:133-151. doi:10.1007/978-1-62703-764-8_10S1331511116Haseloff J, Ajioka J (2009) Synthetic biology, history, challenges and prospects. J R Soc Interface 6(Suppl 4):S389–S391Check E (2005) Synthetic biology, designs on life. Nature 438:417–418Kosuri S, Eroshenko N, LeProust EM et al (2010) Scalable gene synthesis by selective amplification of DNA pools from high-fidelity microchips. Nat Biotechnol 28:1295–1299Ellis T, Adie T, Baldwin GS (2011) DNA assembly for synthetic biology, from parts to pathways and beyond. Integr Biol 3:109–118Gibson DG, Young L, Chuang R-Y et al (2009) Enzymatic assembly of DNA molecules up to several hundred kilobases. Nat Methods 6: 343–345Gibson DG, Glass JI, Lartigue C et al (2010) Creation of a bacterial cell controlled by a chemically synthesized genome. Science 329:52–56Sarrion-Perdigones A, Falconi EE, Zandalinas SI et al (2011) GoldenBraid, an iterative cloning system for standardized assembly of reusable genetic modules. PLoS One 6:e21622Sarrion-Perdigones A, Vilar-Vazquez M et al (2013) GoldenBraid2.0, A comprehensive DNA assembly framework for plant synthetic biology. Plant Physiol 162:1618–1631Engler C, Gruetzner R, Kandzia R (2009) Golden gate shuffling, a one-pot DNA shuffling method based on type IIs restriction enzymes. PLoS One 4:e5553Engler C, Kandzia R, Marillonnet S (2008) A one pot, one step, precision cloning method with high throughput capability. PLoS One 3:e3647Bracha-Drori K, Shichrur K, Katz A et al (2004) Detection of protein-protein interactions in plants using bimolecular fluorescence complementation. Plant J 40:419–427Smaczniak C, Immink RG, Muino JM et al (2012) Characterization of MADS-domain transcription factor complexes in Arabidopsis flower development. Proc Natl Acad Sci U S A 109:1560–1565de Folter S, Immink RG, Kieffer M et al (2005) Comprehensive interaction map of the Arabidopsis MADS Box transcription factors. Plant Cell 17:1424–1433Lorenz WW, McCann RO, Longiaru M et al (1991) Isolation and expression of a cDNA encoding Renilla reniformis luciferase. Proc Natl Acad Sci U S A 88:4438–4442Voinnet O, Pinto YM, Baulcombe DC (1999) Suppression of gene silencing: a general strategy used by diverse DNA and RNA viruses of plants. Proc Natl Acad Sci U S A 96: 14147–14152Hellens RP, Edwards EA, Leyland NR et al (2000) pGreen: a versatile and flexible binary Ti vector for Agrobacterium-mediated plant transformation. Plant Mol Biol 42:819–832Butelli E, Titta L, Giorgio M et al (2008) Enrichment of tomato fruit with health-promoting anthocyanins by expression of select transcription factors. Nat Biotechnol 26: 1301–1308Kapila J, DeRycke R, VanMontagu M et al (1997) An Agrobacterium-mediated transient gene expression system for intact leaves. Plant Sci 122:101–10

    Metaphorical and interlingual translation in moving organizational practices across languages

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    Organizational scholars refer to translation as a metaphor in order to describe the transformation and movement of organizational practices across institutional contexts. However, they have paid relatively little attention to the challenges of moving organizational practices across language boundaries. In this conceptual paper, we theorize that when organizational practices move across contexts that differ not only in terms of institutions and cultures but also in terms of languages, translation becomes more than a metaphor; it turns into reverbalization of meaning in another language. We argue that the meeting of languages opens up a whole new arena for translator agency to unfold. Interlingual and metaphorical translation are two distinct but interrelated forms of translation that are mutually constitutive. We identify possible constellations between interlingual and metaphorical translation and illustrate agentic translation with published case examples. We also propose that interlingual translation is a key resource in the discursive constitution of multilingual organizations. This paper contributes to the stream of research in organization studies that has made translation a core aspect of its inquiry

    Advances in low-memory subgradient optimization

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    One of the main goals in the development of non-smooth optimization is to cope with high dimensional problems by decomposition, duality or Lagrangian relaxation which greatly reduces the number of variables at the cost of worsening differentiability of objective or constraints. Small or medium dimensionality of resulting non-smooth problems allows to use bundle-type algorithms to achieve higher rates of convergence and obtain higher accuracy, which of course came at the cost of additional memory requirements, typically of the order of n2, where n is the number of variables of non-smooth problem. However with the rapid development of more and more sophisticated models in industry, economy, finance, et all such memory requirements are becoming too hard to satisfy. It raised the interest in subgradient-based low-memory algorithms and later developments in this area significantly improved over their early variants still preserving O(n) memory requirements. To review these developments this chapter is devoted to the black-box subgradient algorithms with the minimal requirements for the storage of auxiliary results, which are necessary to execute these algorithms. To provide historical perspective this survey starts with the original result of N.Z. Shor which opened this field with the application to the classical transportation problem. The theoretical complexity bounds for smooth and non-smooth convex and quasi-convex optimization problems are briefly exposed in what follows to introduce to the relevant fundamentals of non-smooth optimization. Special attention in this section is given to the adaptive step-size policy which aims to attain lowest complexity bounds. Unfortunately the non-differentiability of objective function in convex optimization essentially slows down the theoretical low bounds for the rate of convergence in subgradient optimization compared to the smooth case but there are different modern techniques that allow to solve non-smooth convex optimization problems faster then dictate lower complexity bounds. In this work the particular attention is given to Nesterov smoothing technique, Nesterov Universal approach, and Legendre (saddle point) representation approach. The new results on Universal Mirror Prox algorithms represent the original parts of the survey. To demonstrate application of non-smooth convex optimization algorithms for solution of huge-scale extremal problems we consider convex optimization problems with non-smooth functional constraints and propose two adaptive Mirror Descent methods. The first method is of primal-dual variety and proved to be optimal in terms of lower oracle bounds for the class of Lipschitz-continuous convex objective and constraints. The advantages of application of this method to sparse Truss Topology Design problem are discussed in certain details. The second method can be applied for solution of convex and quasi-convex optimization problems and is optimal in a sense of complexity bounds. The conclusion part of the survey contains the important references that characterize recent developments of non-smooth convex optimization

    Sorption-Desorption Behavior of Atrazine on Soils Subjected to Different Organic Long-Term Amendments

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    Sorption of atrazine on soils subjected to three different organic amendments was measured using a batch equilibrium technique. A higher K(F) value (2.20 kg(-1)(mg L(-1))(-)N) was obtained for soil fertilized with compost, which had a higher organic matter (OM) content. A correlation between the K(Foc) values and the percentage of aromatic carbon in OM was observed. The highest K(Foc) value was obtained for the soil with the highest aromatic content. Higher aromatic content results in higher hydrophobicity of OM, and hydrophobic interactions play a key role in binding of atrazine, On the other hand, the soil amended with farmyard manure had a higher content of carboxylic units, which could be responsible for hydrogen bonding between atrazine and OR Dominance of hydrogen bonds compared to hydrophobic interactions can be responsible for the lower desorption capacity observed with the farmyard manure soil, The stronger hydrogen bonding can reduce the leaching of atrazine into drinking water resources and runoff to rivers and other surface waters

    Universities’ pursuit of inclusion and its effects on professional staff: the case of the United Kingdom

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    This paper explores the proliferation of non-academic professionals as a cultural response to universities’ mission of inclusion. Departing from a neo-institutionalist perspective, the author argues that the diffusion of highly rationalised models of institutional action shapes universities as formal organisations who engage with new levels of professional expertise in the pursuit of goals and missions. The United Kingdom (UK) offers an illustrative example, the emergence of statutory equality duties on public institutions (race equality duty 2001, disability equality duty 2006 and gender equality duty 2007) nurturing an image of universities as strategic for the pursuit of demographic inclusion. Using yearly longitudinal data on 109 UK universities from 2003 to 2011, the author shows that universities increase their professional staff in catering for demographic inclusion in terms of ethnicity and disability, revealing highly rationalised institutional responses to the aforementioned equality duties. The findings contribute to the neo-institutionalist literature drawing attention to the transformation of universities into organisational actors (i.e. highly integrated entities, strategically oriented towards the pursuit of formally articulated goals and targets), which contrasts with traditional conceptions of the university as an institution with a taken-for-granted societal role and loosely defined organisational backbone. The findings provide the impetuous for further empirical research into the role of professional staff as universities assimilate new goals and missions

    Administrators in higher education: organizational expansion in a transforming institution

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    Recent European research has revealed growth in the number of administrators and professionals across different sections of universities—a long established trend in US universities. We build on this research by investigating the factors associated with variation in the proportion of administrators across 761 Higher Education Institutions (HEIs) in 11 European countries. We argue that the enactment of expanded and diversified missions of HE is one of the main factors nurturing universities’ profesional and administrative bodies. Our findings support such an assertion; regardless of geographical and institutional differences, HEIs with high levels of “entrepreneurialism” (e.g. in service provision and external engagement) are characterized by a larger proportion of administrative staff. However, we find no empirical support for arguments citing structural pressures and demands on HEIs due to higher student enrolments, budget cuts or deregulation as engines driving such change. Instead, our results point towards, as argued by neo-institutionalists, the diffusion of formal organization as a model of institutional identity and purpose, which is especially prevalent at high levels of external connectedness
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