Toward a Comprehensive Approach to the Collection and Analysis of Pica Substances, with Emphasis on Geophagic Materials

Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem.In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica.Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles.This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption

Paleontology of leaf beetles

`The rate of evolution in any large group is not uniform; there are periods of relatise stability, and periods of comparatively rapid change.' Cockerell and LeVeque, 1931 To Yenli Ych, my beloved wife, a most wonderful person! The fossil record of the Chrysomelidae can be tentatively traced back to the late Paleozoic to early Mesozoic Triassic. Mesozoic records at least 9 subfamilies, 19 genera, and 35 species, are represented by the Sagrinae, the exclusively Mesozoic Proto scelinae, Clytrinae, Cryptocephalinae, Eumolpinae, Chrysomelinae. Galerucinac, Alticinae, and Cassidinae. Cenozoic records at least 12 subfamilies- 63 % of the extant- 12! genera, and 325 species, include the same extant subfamilies as well as the Donaciinae, Zeugophorinae, Criocerinae, and Hispinae and can be frequently identified to genus, especially if preserved in amber. Quaternary records are often identified to extant species. tn total, at least t3! genera about 4 % of total extant, and 357 species < 1 % have been reported. At least, 24 genera <1 % of the extant seem to be extinct. Although reliable biological information associated with the fossil chrysomelids is very scarce, it seems that most of the modern host-plant associations were established, at least, in the late Mesozoic to early Cenozoic. As a whole, stasis seems to be the general rule of the chrysomelid fossil record. Together with other faunal elements, chrysomelids, especially donaciines, have been used as biogeographic and paleoclimatological indicators in the Holocene. I

Expectation Gap and Corporate Fraud: Is Public Opinion Reconcilable with Auditors’ Duties?

The objective of this paper is to answer the key question of whether auditors’ view of their fraud detection duties is reconcilable with the public’s view. We perform a content analysis of press articles covering 37 U.S. corporate fraud cases discovered during the period 1992-2005. We compare the auditors’ duties (as described by the auditing standards) with the public opinion represented by these press articles. Consistent with Porter (1993), we identify three types of divergence between public expectations and auditing standards: deficient performance (that we label “Type 1”), deficient standards (“Type 2”) and unreasonable expectations (“Type 3”). The Type 1 gap can be reduced by strengthening auditors’ willingness and ability to apply existing auditing standards on fraud detection. The Type 2 gap can be narrowed by improving the existing auditing standards. The Type 3 gap, however, concerns highly subjective criteria beyond the auditors’ usual sphere of control. The results of our analysis confirm that the expectation gap is unlikely to disappear given that the rational auditor is unable or unwilling to assess the subjective components of fraudulent behavior, and that value judgments, as demonstrated in the media, retain their popularity

Kinetic analysis of PI3K reactions with fluorescent PIP2 derivatives

PI3K signaling plays important roles in cell differentiation, proliferation, and migration. Increased mutations and expression levels of PI3K are hallmarks for the development of certain cancers. Pharmacological targeting of PI3K activity has also been actively pursued as a novel cancer therapeutic. Consequently, measurement of PI3K activity in different cell types or patient samples holds the promise as being a novel diagnostic tool. However, the direct measurement of cellular PI3K activity has been a challenging task. We report here the characterization of two fluorescent PIP(2) derivatives as reporters for PI3K enzymatic activity. The reporters are efficiently separated from their corresponding PI3K enzymatic products through either thin layer chromatography (TLC) or capillary electrophoresis (CE), and can be detected with high sensitivity by fluorescence. The biophysical and kinetic properties of the two probes are measured, and their suitability to characterize PI3K inhibitors is explored. Both probes show similar capacity as PI3K substrates for inhibitor characterization, yet also possess distinct properties that may suggest their different applications. These characterizations have laid the groundwork to systematically measure cellular PI3K activity, and have the potential to generate molecular fingerprints for diagnostic and therapeutic applications