Conditional and Unconditional Simulation of Healthy Patients' Visual Fields

This paper describes a simulation problem, motivated by the study of glaucoma, a very serious and widespread ocular illness. To ascertain whether a patient suffers from glaucoma, a perimetric test is done, but the evolution of the disease is very slow, and large longitudinal sets of tests taken on the same patient are needed to study its evolution, to analyze the efficiency of existing methods to detect the progression of glaucoma and to develop new ones. Simulation can be a very useful procedure to get appropriate data sets to work with. Our aim in this work is to simulate several VFs in a healthy patient to reflect his evolution in time. We use a spatio‐temporal model to simulate from, taking into account the correlation existing between the observed (or simulated) values in space and time. Two different simulation procedures (unconditional and conditional) are studied, and applied to obtain the simulations we are interested in. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Changes in hypoxia tolerance during metamorphosis of bonefish leptocephali

Survival times of metamorphosing leptocephali of the bonefish Albula sp. placed in hypoxic sea water (0·68 mg O₂ l^-1) decreased by about three-fold (from c. 15 to 5 min) over the 10 day metamorphic period. Increased sensitivity to hypoxia coincided with increased larval oxygen demand during metamorphosis. Plots of hypoxic survival time against standard length or wet mass suggested that metamorphosis (phase II of larval development) could be divided into subphases (IIa and IIb). American Public Health Association.     

Presence of haemocyte-like cells in coccinellid reflex blood

Abstract.  Contrary to current assumptions, the reflex blood of two-spot ladybirds, Adalia bipunctata , and seven-spot ladybirds, Coccinella septempunctata , contains haemocyte-like cells. Furthermore, DNA can be extracted and amplified from coccinellid reflex blood, confirming the presence of haemocyte-like cells and demonstrating a nondestructive method of DNA extraction.     

Don C. Ohadike: The Man, his Intellectual Legacy and African Historiography

It is difficult to completely understand the life history of an intellectual excluding an understanding of his family upbringing and formative years. Family upbringing and childhood environment, often the less known part of a life history, play crucial roles in shaping the ideas and values individuals espouse in their adult life. Notwithstanding, this paper is not concerned with Don C. Ohadike’s childhood. It rather focuses on the professional career of our able historian – that is the part of his life as revealed by his most outstanding published writings. Ohadike’s published works contain a wellspring of idioms that tell much about his values, quality of mind, and his mission as an African historian. Ohadike was a humanist, an African patriot, and a nationalist crusader. His entire philosophy centered on safeguarding his African identity in an emergent world of cultural imperialism. The funds for this research were provided by a NEH-funded fellowship at the Schomburg Center, New York in the Spring of 2007. I owe a lot of gratitude to Professor John McLeod and Dean Blaine Hudson for granting me the extra incentives to pursue my research in New York. While all errors and misinterpretations are mine, I wish to thank the editors and anonymous reviewers for Journal of Dialectical Anthropology for their perspective comments and suggestions on earlier drafts of this paper.     

Comparative responses of Achillea millefolium ecotypes to competition and soil type

Summary Achillea millefolium populations from adjacent sites with zonal and serpentime soil were used to test predictions about the relation between growth and the competitive ability of plants in productive and unproductive environments. Under greenhouse conditions, individually-grown plants from both sources grew larger in serpentine soil than in zonal soil; serpentine plants accumulated 72% more biomass than zonal plants. In zonal soil, zonal plants were 71% larger than serpentine plants, although these differences were not statistically significant, and plants from both sources accumulated much less biomass and were shorter than plants growing in serpentine soil. In a high density, fertilized replacement series, zonal plants were taller and heavier but exhibited no more competitive ability than serpentine plants. The predictions that rapid height growth and biomass accumulation contribute significantly to competitive ability are not supported by our results. Although ecotypic differentiation has occurred between these A. millefolium populations, apparently in response to different soil types, the expression of these heritable differences can be masked by other environmental effects. There has been no apparent trade-off in these ecotypes between their response to the physical environment and their competitive ability.     

Induced tolerance of neonate Heliothis zea to host plant allelochemicals and carbaryl following incubation of eggs on foliage of Lycopersicon hirsutum f. glabratum

Summary Incubation of Heliothis zea (Boddie) eggs on foliage of Lycopersicon hirsutum f. glabratum C.H. Mull (accession PI 134417) results in neonates with elevated levels of tolerance to the toxic effects of PI 134417 foliage attributable to 2-tridecanone found in the glandular trichomes which abound on that foliage. The neonates from such eggs are also shown to have elevated levels of tolerance to the carbamate insecticide carbaryl. Incubation of eggs in an atmosphere containing 2-tridecanone similarly produced elevated levels of tolerance to 2-tridecanone among resulting neonates, indicating that 2-tridecanone is the likely inducing agent and that exposure to 2-tridecanone vapor, which is known to emanate from PI 134417 foliage, is sufficient for induction. Analysis of the cytochrome P-450 content in gut microsomes of fifth instar larvae indicated that exposure of larvae to 2-tridecanone in artificial diet or to PI 134417 foliage resulted in significantly elevated levels of cytochrome P-450 relative to larvae fed diet without 2-tridecanone or foliage of L. esculentum which contains no 2-tridecanone. In addition, removal of the glandular trichomes from PI 134417 foliage eliminated the ability of that foliage to induce elevated levels of cytochrome P-450. These results provide circumstantial evidence that cytochrome P-450 may be involved in the induced tolerance to xenobiotics among neonates from eggs exposed to 2-tridecanone or PI 134417 foliage.Support for this research was provided by the USDA Competitive Research Grants Program in Biological Stress under Grant No. 83-CRCR-1-1241 and Grant No. 85-CRCR-1-1615, and the North Carolina Agricultural Research Service. Paper No. 10856 of Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC, USA 27650. Use of trade names does not imply endorsement of products named nor criticisms of similar ones not mentioned     

Activation of fatty acids by non-glyoxysomal peroxisomes

Ethylene treatment (approx. 20 l ·1^-1 in air for 2 d) of tobacco (Nicotiana tabacum L. cv. Havana 425) plants markedly increases the endo--1,3-glucanase (EC 3.2.1.39) content of leaves. The antigenic form of the enzyme induced is the same one whose production is blocked by treating cultured cells with combinations of auxin (1.1 · 10^-5 M -naphthaleneacetic acid) and cytokinin (1.4 · 10^-6 M kinetin). Evidence is presented that cultured tobacco cells require ethylene for -1,3-glucanase accumulation: i) ethylene treatment increased the accumulation of \-1,3-glucanase in callus tissues >10 d after subculturing and in cell-suspension cultures; ii) callus tissues can produce ethylene; iii) conditions known to inhibit ethylene production (1 mM CoCl₂; 33° C treatment) or ethylene action (approx. 1.6 mmol · 1^-1 norbornadiene in air) inhibited -1,3-glucanase accumulation by callus tissues treated for 4 d following subculturing; and, these inhibitory effects were prevented by exogenous ethylene. Combinations of auxin and cytokinin blocked ethylene-induced accumulation of -1,3-glucanase by cell-suspension cultures. The results favor a model in which ethylene induces results favor a model in which ethylene induces 1,3-glucanase accumulation, and auxin and cytokinin inhibit this induction process.Abbreviations NAA -naphthaleneacetic acid - NDE norbornadiene     

Ethylene production in habituated and auxin-requiring tobacco callus cultures. Does ethylene play a role in the habituation?

Ethylene production of habituated and auxin-requiring tobacco ( Nicotiana tabacum L. cv. Xanthi) callus cultures were compared. More ethylene was produced by auxinrequiring i.e. auxin-heterotrophic cultures than by habituated ones. Treatment with 2,4-dichlorophenoxyacetic acid increased the ethylene evolution of habituated cultures over the range 10⁻⁷ to 10⁻⁴ M , which suggests that the higher ethylene production of auxin-dependent callus is caused by the 2,4-D in the medium. The IAA levels depended on the age of both types of callus cultures.