178 research outputs found
Pseudoceros vishnui Dixit, Raghunathan & Chandra, 2017, sp. nov.
No full textPseudoceros vishnui sp. nov. Figures 6–8; Table. 1 Type material: Holotype: One specimen (20 x 15 mm) as serial sections of reproductive structures (7 Slides), remainder of animal in 70% ethanol. Collected 19.03.2015, subtidally from 10 m depth, Pongibalu (Lat: 11°30.573’N, Long: 92°39.123’E), South Andaman, India (ZSI/ANRC-16841). Paratypes: One specimen (15 x 10 mm) as serial sections of reproductive structures (5 Slides), remainder of animal in 70% ethanol. Same as holotype (ZSI/ANRC-16842). One specimen (11 x 8 mm) in 70% EtOh. Collected 0 8.09.2015, subtidally from 15 m depth, Pongibalu (Lat: 11°30.573’N, Long: 92°39.123’E), South Andaman, India (ZSI/ANRC-16843). One specimen (11 x 8 mm) in 70% EtOh. Collected 15.12.2016, subtidally from 9 m depth, Rutland Island (Lat: 11°30.119’N, Long: 92°37.112’E), South Andaman, India (ZSI/ANRC-16844). Distribution. Pongibalu, South Andaman, India. Additional photographic record from Burma (Newman & Cannon, 2005). Diagnosis. Body colour cream, solid purple to violet spots all over body. Margin made up of non-continuous dark blue spots of various sizes. Etymology. This species is named after Vishnu Kumar Dixit, father of the first author, in acknowledgment of his support throughout his research on marine flatworms. Synonyms. It is likely that it corresponds to Pseudoceros sp. 38, Newman & Cannon (2005), CD-ROM and to Pseudoceros sp., Kuiter & Debelius (2009), see taxonomic remarks below. Description. Live. Body oval and smooth, margin without any ruffles. Many purple to violet coloured spots, of variable sizes, more or less circular are present all over the body (Fig. 6A, B). Blue pseudotentacles, small, formed by simple folds of the anterior margin with scattered eyespots on each pseudotentacle on either side. Cerebral eyespot cluster with 40–43 eyes (Fig. 6 C). Ventral side cream in colour. Margin made up of small blue coloured discontinuous spots of various sizes. Preserved. Holotype 15 mm long and 12 mm wide at central portion. Translucent due to loss of colour on fixation but some faint purple spots visible in paratype specimen. Dorsal epidermis very rough and uneven with thickens 45 to 55 µm and is twice the thickness of ventral epidermis which is 18–22 µm and smooth. Nucleus present at the base while rhabdites near dorsal surface. A distinct basement membrane clearly separates epithelium from underlying muscles. Distance between pharyngeal mouth and sucker is 4.53 mm. Male and female gonopores 1.03 mm apart. Pharynx small and ruffled with 7 folds. Male pore 1.93 mm from pharyngeal mouth and is situated between last pair of pharyngeal folds. Sucker 1.3 mm from female pore. Reproductive characters. Measurements refer to length in a 15 mm long worm, the holotype. Seminal vesicle (Fig. 7 A) elongate and oval (490 x 421 µm), heavily muscularized, parallel to longitudinal body axis. Prostatic vesicle (Fig. 7 A) located anterior to seminal vesicle and just above male atrium. It is slightly tapering in shape downwards (180 x 168 µm) with thickness of inner wall varying from 30 to 50 µm. Male atrium deep with many folds and stylet 197 µm long. Female atrium 188 µm long while vagina is 384 µm long tube curved towards posterior end. Well defined cement pouches with numerous cement glands present (Fig. 7 B & 8). Taxonomic remarks. The presence of this species is recorded on many occasions from Andaman Islands (Sreeraj & Raghunathan 2013; Sreeraj et al. 2015); however, no attempt had been made in the past to make a formal description. To date, only 4 species under the genus Pseudoceros are described from India: Pseudoceros gamblei Laidlaw, 1902; P. tigrinus Laidlaw, 1902; P. galatheensis Dixit et al. 2017 and P. nigropunctatus Dixit et al. 2017. The general spotted pattern of newly described species P. vishnui sp. nov. resembles with P. nigropunctatus described from same geographical area but the difference in appearance and colour of the spots on dorsal surface and background colour distinguish them from one another. In addition, P. laingensis Newman & Cannon, 1998 described from Papua New Guinea is the most resembled species to P. vishnui sp. nov. in terms of margins, background colour and spots. Both species have purple spots on dorsum but the spots in P. laingensis are smaller and more in number in comparison to P. vishnui sp. nov. with bigger and few spots. Border of P. laingensis is made up of numerous purple spots (same colour as that of spots on dorsum) of different sizes (Bolanos et al. 2016) while the border of P. vishnui sp. nov. is characterised by numerous spots of blue colour and never of same colour as of spots on dorsum. Bolanos et al (2016) mentioned that the purple dots on the dorsal surface of P. laingensis were numerous in some individuals but scarce in others while the frequency of spots in P. vishnui sp. nov. remained almost similar in all the studied individuals. There are few more species under the genus Pseudoceros with presence of spots on their body namely Pseudoceros nipponicus Kato, 1944; P. lindae Newman & Cannon, 1994 and P. scintillatus Newman & Cannon, 1994. P. nipponicus have black spots on the dorsum and a russet brown sub marginal band with a black rim while P. lindae is characterised by golden yellow spots on dorsum. In P. scintillatus the spots are very big, differently coloured, clearly outlined and touching the margin. Newman & Cannon, 2005 reported this undescribed species as Pseudoceros sp. 38 from Burma and mentioned colour of spots as red and margins to be made up of purple spots. Kuiter & Debelius (2009) also reported this species as Pseudoceros sp. from Andaman Sea based on photographic record. But the overall appearance and pattern of the species agrees to the newly described species and existence of both in same geographical area led us to assume that both can be same species. Table. 1 is provided with detailed comparisons between newly described species and similarly coloured species. TABLE. 1. Comparison of Pseudoceros vishnui sp. nov. characters with similarly coloured and patterned species.Published as part of Dixit, Sudhanshu, Raghunathan, C. & Chandra, Kailash, 2017, Two new Pseudoceros (Polycladida: Pseudocerotidae) and a Prostheceraeus (Polycladida: Euryleptidae) from Andaman and Nicobar Islands, India, pp. 495-512 in Zootaxa 4269 (4) on pages 501-503, DOI: 10.11646/zootaxa.4269.4.5, http://zenodo.org/record/58274
Risk - adjusted rates of return for project appraisal
No full textIncorporating risk assessment into public project appraisal makes sense when project risk is significantly correlated with uncertainty about national income. It is especially important in countries that specialize in particular agricultural or resource sectors. This report presents the following conclusions: (a) risk corrections can be substantial; (b) the intuition that risk is great for further investment in a crop or sector that constitutes a large part of a country's GNP is not invalid, but the effect may be offset by other forces in operation; (c) risk corrections can be negative because of a negative correlation between project return and GNP; (d) risk premia vary greatly across countries and sectors - so recognizing the risk correction needed for each project on its own merits makes more sense than including a common general risk premium in the rate of return required for all lending; (e) risk corrections are small for many sectors and countries - so efforts can be concentrated on the other categories, where the proposed treatment of risk makes a big difference; (f) risk affects investment projects in many different, subtle ways; and (g) resource requirements for this are not great.Environmental Economics&Policies,Health Economics&Finance,Banks&Banking Reform,Statistical&Mathematical Sciences,Crops&Crop Management Systems
How expectations affect reform dynamics in developing countries
No full textReform is often flawed by delayed implementation and, after initial acceptance, sudden reversals in public reaction. In recent years, many attribute these delays and reversals to reform dynamics because reform, particularly when comprehensive, rarely takes place all at once. In designing reform, it is important to determine what the best sequencing of reform would be, under what conditions that sequence is feasible, and how expectations will affect the success of alternative reform strategies. In the literature on second-best reform strategies, misperceptions about the prospective costs and benefits of reform add another intertemporal distortion to the many already identified. Bold moves, such as pre-announced institutional changes, are often suggested as a way to signal the beginning of a new policy regime. The author advocates a more cautious approach when a government has been discredited by a history of policy failures.Environmental Economics&Policies,Macroeconomic Management,Economic Stabilization,Insurance&Risk Mitigation,Economic Theory&Research
Hypoxia activates IKK-NF-κB and the immune response in <em>Drosophila melanogaster</em>
No full textHypoxia, or low oxygen availability, is an important physiological and pathological stimulus for multicellular organisms. Molecularly, hypoxia activates a transcriptional programme directed at restoration of oxygen homoeostasis and cellular survival. In mammalian cells, hypoxia not only activates the HIF (hypoxia-inducible factor) family, but also additional transcription factors such as NF-?B (nuclear factor ?B). Here we show that hypoxia activates the IKK–NF-?B [I?B (inhibitor of nuclear factor ?B)–NF-?B] pathway and the immune response in Drosophila melanogaster. We show that NF-?B activation is required for organism survival in hypoxia. Finally, we identify a role for the tumour suppressor Cyld, as a negative regulator of NF-?B in response to hypoxia in Drosophila. The results indicate that hypoxia activation of the IKK–NF-?B pathway and the immune response is an important and evolutionary conserved response.</p
Sustainability : ethical foundations and economic properties
No full textThe author interprets development to be sustainable if it involves a nondecreasing quality of life. He introduces a concept of justice, and shows that a development path must be sustainable to prevent injustice. He argues, and illustrates through growth models, that altruism alone does not - even in the context of an economically efficient market economy - ensure sustainability. In particular, technologies with complementarity between manmade and natural capital represent cases where sustainability need not result. Thus, policies aimed at economic efficiency, such as internalizing external effects, need not generate sustainable development. The author argues that a positive interest rate is not inconsistent with sustainable development. He also maintains that, even in a perfect market economy, prices may not convey whether investments in manmade capital are sufficient to compensate for the depletion of natural capital. In particular, a non-negative market value of net investment is not sufficient for the present quality of life to be sustainable. Finally, he emphasizes that public policy aimed at sustainable development should strengthen the mechanisms for redistribution from the present to the future.Economic Theory&Research,Environmental Economics&Policies,Banks&Banking Reform,International Terrorism&Counterterrorism,Development Economics&Aid Effectiveness
Large values of -functions on the -line
No full textIn this paper, we study lower bounds of a general family of - functions on the -line. More precisely, we show that for any in this family, there exists arbitrary large such that , where is the order of the pole of at . This is a generalization of the same result of Aistleitner, Munsch and the second author for the Riemann zeta-function. As a consequence, we get lower bounds for large values of Dedekind zeta-functions and Rankin-Selberg - functions of the type on the -line
Revenue-productive income tax structures and tax reforms in emerging market economies - evidence from Bulgaria
No full textUsing a household budget survey for 1992, The author shows the poor revenue performance and distributional impact of Bulgaria's personal income tax system. He explores the implications for revenue and income distribution of two alternative tax systems - a flat tax and a progressive but simpler three-brackets tax system. He demonstrates that simpler tax structures with lower tax rates could achieve at least equal revenue and distributional objectives and are superior in terms of efficiency and equity. (The findings are robust when Bulgaria's significant tax evasion is included). But tax changes since 1992 have, if anything, moved Bulgaria even further from a simple income tax system: the number of rates and brackets increased from 7 to 10, and the levels of exemption remain unchanged. (Complex, higher rates complicate administration and enforcement and provide incentives for tax evasions. And in the alternative systems the author explores, the poor are protected with higher exemptions.) Fortunately, the country's personal income tax structure began to move toward less nominal progressivity after Bulgaria's 1997 tax reform program. The tax rate in thetop income bracket was reduced from 52 percent to 40 percent, the number of tax brackets was halved, and the exemption level was increased 20 percent (reducing tax burdens on the poor).Environmental Economics&Policies,Public Sector Economics&Finance,Regional Governance,Tax Policy and Administration,Economic Theory&Research,Governance Indicators,Economic Theory&Research,Public Sector Economics&Finance,Environmental Economics&Policies,Tax Policy and Administration
COVID-19 burden, author affiliation and women's well-being: A bibliometric analysis of COVID-19 related publications including focus on low- and middle-income countries
No full textBACKGROUND: Published literature documents tremendous gender inequities in the social, economic and health effects of the COVID-19 pandemic, but less evidence has come from low- and middle-income countries (LMICs) and even less from LMIC-based authors. We examine whether a) COVID-19 burden and b) LMIC-based authorship were associated with academic publications related to COVID-19 and women's well-being in LMICs. METHODS: We reviewed academic articles on COVID-19 and women's well-being in LMICs published between February 2020 and May 2021 (n=1076 articles), using six electronic databases (PubMed, Web of Science, PsycInfo, EconLit, RePeC, NBER). Multilevel, mixed effects linear regressions assessed the relationships between each of our independent variables - a) COVID-19 burden (cases/100 population, deaths/100 population, deaths/cases) and b) author's country of primary affiliation, with publications related to COVID-19 and women's well-being, both overall and stratified by country income group. FINDINGS: Eight-eight percent of articles had lead and/or senior authors affiliated with in-country institutions. Linear mixed effect models indicate that COVID-19 cases and case fatality ratios in a country were significantly and positively associated with the number of publications related to COVID-19 and women's well-being, though these relationships were significant only in upper-middle income group countries in stratified analyses. LMIC lead and senior authorship were also significantly and positively associated with our outcome, after adjusting for COVID-19 burden. INTERPRETATION: While the majority of COVID-19 research examining women's well-being in LMICs in the first year and a half of the pandemic included country-affiliated author leadership, there were important gaps in representation. Findings highlight the importance of LMIC-based scholars to build local and gendered research in crises. FUNDING: Bill and Melinda Gates Foundation (INV-018007)
An effective bound on Generalized Diophantine m-tuples
No full textFor non-zero integers and , a generalized Diophantine -tuple
with property is a set of positive integers such that is a -th power for . Define
has property . In a recent work, the second
author, S. Kim and M. R. Murty proved that is , for a fixed
, as we vary . In this paper, we obtain effective upper bounds on
. In particular, we show that for , , if is sufficiently larger than
Application of stochastic differential games and real option theory in environmental economics
No full textThis thesis presents several problems based on papers written jointly by the author and Dr. Christian-Oliver Ewald. Firstly, the author extends the model presented by Fershtman and Nitzan (1991), which studies a deterministic differential public good game. Two types of volatility are considered. In the first case the volatility of the diffusion term is dependent on the current level of public good, while in the second case the volatility is dependent on the current rate of public good provision by the agents. The result in the latter case is qualitatively different from the first one. These results are discussed in detail, along with numerical examples. Secondly, two existing lines of research in game theoretic studies of fisheries are combined and extended. The first line of research is the inclusion of the aspect of predation and the consideration of multi-species fisheries within classical game theoretic fishery models. The second line of research includes continuous time and uncertainty. This thesis considers a two species fishery game and compares the results of this with several cases. Thirdly, a model of a fishery is developed in which the dynamic of the unharvested fish population is given by the stochastic logistic growth equation and it is assumed that the fishery harvests the fish population following a constant effort strategy. Explicit formulas for optimal fishing effort are derived in problems considered and the effects of uncertainty, risk aversion and mean reversion speed on fishing efforts are investigated. Fourthly, a Dixit and Pindyck type irreversible investment problem in continuous time is solved, using the assumption that the project value follows a Cox-Ingersoll- Ross process. This solution differs from the two classical cases of geometric Brownian motion and geometric mean reversion and these differences are examined. The aim is to find the optimal stopping time, which can be applied to the problem of extracting resources
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