Influence of Lead, an Environmental Pollutant on Metamorphosis of Rana utricularia (Amphibia: Ranidae)

The influence of lead, an environmental pollutant on metamorphosis of Rana utricularia, was examined in this study. Larvae of stage XI (Taylor and Kollros, 1946), beginning of the premetamorphic stage, were exposed to lead concentrations of 0.1 ppm, 0.5 ppm, 1.0 ppm and 1.5 ppm for 106 days. The untreated larvae served as controls. Larvae were observed from early limb bud stage, stage X, through the protrusion of the forelimbs, stage XX. Neither the sequence of developmental events nor the gross external and internal morphology was altered by lead. However, lead prolonged the time of metamorphosis by delaying the completion of each successive prometamorphic stage. The extent of delay was concentration dependent. The thyroid gland of the experimental larvae underwent alterations which were also concentration dependent. The size of the gland and the size of the follicle were reduced. Vacuolation occurred in the colloid of both 0.5 ppm and 1.5 ppm lead treated larvae

THE ASIAN WOMAN IN AMERICA

Both females and males, regardless of their racial ethnic group, are seriously limited in their information about Asian women. Far too often the system educates individuals about race and sex as two distinct and separate categories. Consequently, Asian women, as well as other women of color, are viewed either as members of their ethnic group or their sexual group, and rarely as members of both groups simultaneously. This paper presents an overview of the historical context and the present-day status of Asian women in America as well as implications for education and change

What is economic personalism? A phenomenological analysis

Much like phenomenology, the philosophical movement of economic personalism has preceded its complete and clear awareness of itself as a philosophical position. This paper attempts to articulate what exactly this position is by employing realist phenomenology as its analytical tool. The organization of this paper consists of three parts. The first is a linguistic analysis of the names 'economics' and 'personalism' that attempts to arrive at a joint meaning of these terms. The second is a regressive inquiry from meaning to a priori apprehension, and this examination is aimed at making the essential nature of economic personalism perspicuous. The third presents the necessary and sufficient conditions for either conduct or a situation to quality as a object in the domain of economic personalism.economic personalism; personalism; phenomenology; economic value; moral value; social ontology; ontology of economics; philosophy of economics

An Ontology Of Economic Objects

Economic reality is constituted by economic objects such as goods, commodities, money, value, price, and exchange that, together, give rise to the complex entity known as the market. Each of these categories is governed by exact laws that provide the conditions for settling objectively whether individuals' views about an instance of any category indeed correspond to that category. This paper describes such laws for each category. The aim of this paper is to lay the groundwork for an ontological description of economic reality.economic reality; social ontology; economic categories; economic objects; goods; commodities; money; value; price; exchange; philosophy of economics

Truth in Economic Subjectivism

The notion of subjectivism has a significant place in the body of economic theory, most notably in the theory of economic value. There is, however, one concern that some philosophers have raised about truth in normative judgments that puts economic subjectivism seriously into question. This concern can be articulated as the following question: Do economic value judgments have truth values? The answer to this question is pertinent not only for an improved understanding of economic value but also for such philosophical investigations as realism, epistemology, ontology, and ethics. Nonetheless, the answer is not readily available in the body of economic theory. This paper argues that the truth or falsity of economic judgments can be settled objectively.subjective economic value; subjectivism; objectivism; economic judgments; moral realism; social ontology; philosophy of economics

From Scholarship Girls to Scholarship Women: Surviving the Contradictions of Class and Race in Academe

This article explores the dilemmas graduate education poses for women of working-class origin who come from different ethnic and racial backgrounds. It proceeds in a chronological narrative using examples from the authors\u27 personal experiences to make general points about how the intricate web of class, race, and gender relations shaped their experiences in higher education. Both women -- Cucidraz, a Chicana, and Pierce, a white woman -- struggle with the feelings of alienation and marginality as outsiders within the academy as well as their material needs for financial support. Their personal narratives reveal, as well, how race shapes their experiences in the academy. Racism renders Cuadraz\u27 class status visible, whereas whiteness masks Pierce\u27s background. Finally, the authors shift their focus from an examination of the structures which shaped their lives to an exploration of their attempts to find their own voices in academic work, and to resist the very structures which excluded their experiences as women from working-class backgrounds

A Vavilovian approach to discovering crop-associated microbes with potential to enhance plant immunity

Through active associations with a diverse community of largely non-pathogenic microbes, a plant may be thought of as possessing an “extended genotype,” an interactive cross-organismal genome with potential, exploitable implications for plant immunity. The successful enrichment of plant microbiomes with beneficial species has led to numerous commercial applications, and the hunt for new biocontrol organisms continues. Increasingly flexible and affordable sequencing technologies, supported by increasingly comprehensive taxonomic databases, make the characterization of non-model crop-associated microbiomes a widely accessible research method toward this end; and such studies are becoming more frequent. A summary of this emerging literature reveals, however, the need for a more systematic research lens in the face of what is already a metagenomics data deluge. Considering the processes and consequences of crop evolution and domestication, we assert that the judicious integration of in situ crop wild relatives into phytobiome research efforts presents a singularly powerful tool for separating signal from noise, thereby facilitating a more efficient means of identifying candidate plant-associated microbes with the potential for enhancing the immunity and fitness of crop species

Microscopic Model for Sequential Tunneling in Semiconductor Multiple Quantum Wells

We propose a selfconsistent microscopic model of vertical sequential tunneling through a multi-quantum well.The model includes a detailed description of the contacts,uses the Transfer Hamiltonian for expressions of the current and it treats the Coulomb interaction within a mean field approximation. We analyze the current density through a double well and a superlattice and study the formation of electric field domains and multistability coming from the Coulomb interaction. Phase diagrams of parameter regions (bias, doping in the heterostructure and in the contacts,etc) where the different solutions exist are given.Comment: 4 pages, 8 Postscript Figure