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It is not known how the volume of the cell nucleus is set, nor how the ratio of nuclear volume to cell volume (N/C) is determined. Here, we have measured the size of the nucleus in growing cells of the budding yeast Saccharomyces cerevisiae. Analysis of mutant yeast strains spanning a range of cell sizes revealed that the ratio of average nuclear volume to average cell volume was quite consistent, with nuclear volume being ∼7% that of cell volume. At the single cell level, nuclear and cell size were strongly correlated in growing wild-type cells, as determined by three different microscopic approaches. Even in G1-phase, nuclear volume grew, although it did not grow quite as fast as overall cell volume. DNA content did not appear to have any immediate, direct influence on nuclear size, in that nuclear size did not increase sharply during S-phase. The maintenance of nuclear size did not require continuous growth or ribosome biogenesis, as starvation and rapamycin treatment had little immediate impact on nuclear size. Blocking the nuclear export of new ribosomal subunits, among other proteins and RNAs, with leptomycin B also had no obvious effect on nuclear size. Nuclear expansion must now be factored into conceptual and mathematical models of budding yeast growth and division. These results raise questions as to the unknown force(s) that expand the nucleus as yeast cells grow. © 2007 by The American Society for Cell Biology.

Season-long sampling in streams and rivers produced 112 species of mayflies, which with other records totals 121 species for New Hampshire; 88 of these are new state records. Appearance of blackwing/mature larvae were used to develop statements on seasonality of species. Distinct differences were found between the faunas of southern and north-central New Hampshire, with an important factor being water temperatures through the season. A biogeographic analysis coupled with known habitat preferences reinforced the hypothesis that water temperature was a critical factor in determining species distributions in the state.

The potassium channel protein, Kv3.1, is abundantly expressed in the chick auditory pathway. Its b-isoform is found in nucleus magnocellularis, which receives the cochlear input, both before and after the establishment of synaptic connections. It is also present in cell cultures in the absence of any peripheral input. However, the expression of this isoform in the embryo has been shown to increase with development. Here, we address the question of the correlation between maturation of synapses in the auditory pathway and the pattern of expression of the b-isoform in a series of embryos prepared for immunohistochemistry at Hamburger-Hamilton stages equivalent to E10, E12, E14, and E17. We show here that this subunit translocates from the perinuclear cytoplasm to the cell membrane domain in nucleus magnocellularis at the time that cochlear nerve endings emerge as endbulbs of Held (E17). In nucleus laminaris, by this time, while abundant Kv3.1b occurs in the perinuclear cytoplasm, a translocation to the cell membrane domain has not yet occurred, and the mature peri-synaptic localization is delayed to a later stage. This difference suggests a hierarchy in the developmental expression of Kv3.1. An unexpected finding is the expression of the a-isoform of Kv3.1 in astrocytes, especially those which surround the developing nuclei and their connecting fibers. We also report here for the first time the presence of Kv3.1b in the initial segments of axons at the times when they begin to form. Our observations suggest that the Kv3.1 channel protein is regulated through mechanisms linked to the development of synaptic activity.

This paper examines a little known map of France made around the middle of the fifteenth century, for a genealogical manuscript of the text known as A tous nobles, conserved today as Bibliothèque nationale de France [BnF] MS fr. 4991. It argues that the map's prominence in the manuscript articulates a notion of French identity based on a bond to the territory of France rather than on fealty to its king. Using other images from the manuscript, it considers the importance of geography to the emergence of French national sentiment at the time of the Hundred Years War. © 2007 Elsevier Ltd. All rights reserved.

This article consists of an initial theoretical attempt to describe “interests” as widespread social phenomena which emerge specifically from discursive interaction. I focus on the way in which the indexical signaling of discourse participation roles and public/private standings provide key conditions of possibility for the emergence of interests in interactional real time. The case at hand involves the German welfare state, a social institution which is constituted both on the local level of my fieldsite (a working-class suburb of the former East Berlin) and on the national level (through the popular media and through the circulation of laws, policy documents and the like). [Germany, welfare state, interests, indexical orders, institutionality].

Porosities in the outer table of the cranial vault (porotic hyperostosis) and orbital roof (cribra orbitalia) are among the most frequent pathological lesions seen in ancient human skeletal collections. Since the 1950s, chronic iron-deficiency anemia has been widely accepted as the probable cause of both conditions. Based on this proposed etiology, bioarchaeologists use the prevalence of these conditions to infer living conditions conducive to dietary iron deficiency, iron malabsorption, and iron loss from both diarrheal disease and intestinal parasites in earlier human populations. This iron-deficiency-anemia hypothesis is inconsistent with recent hematological research that shows iron deficiency per se cannot sustain the massive red blood cell production that causes the marrow expansion responsible for these lesions. Several lines of evidence suggest that the accelerated loss and compensatory overproduction of red blood cells seen in hemolytic and megaloblastic anemias is the most likely proximate cause of porotic hyperostosis. Although cranial vault and orbital roof porosities are sometimes conflated under the term porotic hyperostosis, paleopathological and clinical evidence suggests they often have different etiologies. Reconsidering the etiology of these skeletal conditions has important implications for current interpretations of malnutrition and infectious disease in earlier human populations. Am J Phys Anthropol 139:109-125, 2009. (C) 2009 Wiley-Liss, Inc.

Before 2.6 million years ago (Ma), no archaeological record has been securely documented, and therefore there is no evidence of hominin tool use. Then, at 2.6–2.58 Ma, there is widespread evidence for tool manufacture and use at several archaeological sites, with undisputed stone tools and fossil fauna at Gona, Ethiopia. Additionally, the evidence from the earliest archaeological sites at Gona shows that the earliest stone tool makers were skilled flintknappers and were able to select high quality stone raw materials. The possible reasons behind this seeming abrupt transition from the absence of stone tools to the presence thereof include sampling biases, paleogeographic influences, gaps in the geological record, paleoenvironmental change, and changes in the record of hominin evolution.Based on our observations at Gona, the earliest use of flaked stone tools is likely to be slightly older than 2.6 Ma. These stone tools represent a significant change in behavior that set the stage for subsequent hominin evolution. The paleogeographic and paleoenvironmental evidence points to the earliest use of stone tools in certain settings: usually (but not always) close to raw material sources, and ecotones between riparian woodlands and open grasslands. The earliest stone tool makers were proficient, selective, and flexible in their reduction strategies. The variability we see in Pliocene artifact assemblages has much to do with different raw material sources.

The phrase “Developed Oldowan” (DO) was originally coined by M. Leakey to describe a technologically “advanced Oldowan” artifact tradition, that preceded the Acheulian Industry. M. Leakey further identified three stages of the DO which she labeled as the DOA, DOB and DOC. The DO (sensu lato) has been generally recognized as transitional to the Acheulian, but the status of the DOB and the DOC remains unclear. In addition to a lack of clarity in terms of classification, the DO also suffers from a lack of secure radiometric dates, even at Olduvai where it was first identified. Despite such shortcomings, archaeologists still assign assemblages into the DO, as supposedly “intermediate” or transitional between the Oldowan and the Acheulian. However, a closer look at the DO assemblages from Olduvai Gorge and other sites in Africa and the Middle East shows that the artifacts assigned into this tradition are not technologically drastically different from the preceding Oldowan. Probably the flaking characteristics of the raw material types (e.g., quartzite and limestone, and to a lesser extent basalt) and the original shape of the cobbles used by hominins may have played a major role in the final shape of the “distinctive” artifact types (such as spheroids/subspheroids) used for assigning assemblages into the DO. Further, both the DOB and the Acheulian appeared ˜1.7 million years ago (Ma) in the archaeological record, making it unlikely that the DO is a transitional artifact tradition that preceded the Acheulian. Our preliminary evaluation of the archaeological record at Gona, Ethiopia and elsewhere suggests a fairly abrupt appearance of the Acheulian after a temporally rapid transition from the Oldowan.

Laetoli, a paleoanthropological site in Northern Tanzania, is perhaps best known for its famous fossil hominid footprints that were discovered by Mary Leakey and her co-workers in 1978. The site not only preserves the hominid footprints but also trackways, which provide a snapshot of Pliocene faunal communities from East Africa and their inferred environments. Unlike the hominid footprints at site G, which have received tremendous attention, the animal trackways, especially at Localities 7, 8 and 10 have been neglected and are fast disappearing. In this paper, we discuss animal tracks at a newly discovered exposure and provide preliminary data on the tracks at this exposure and other sites. We also discuss the importance of the animal trackways as ecological indicators, which we have investigated as part of ongoing research and conservation efforts initiated by the Tanzania Field School in Paleoanthropology and the Associated Colleges of the Midwest (ACM) Tanzania Semester Abroad programs.

The relationship between artifact manufacture, use, and discard in the Developed Oldowan is complex. Here we use digital-image-analysis techniques to investigate the intensity of reduction in single-platform cores of the Developed Oldowan of the Okote Member, Koobi Fora Formation. Data suggest that this method provides a more accurate measure of reduction intensity than previous applications of a unifacial-scraper model. Assemblages of single-platform cores excavated from extensive lateral exposures of the Okote Member provide insights into the relationship between raw-material availability and discard patterns. Variation in reduction intensity suggests that tools are not always discarded in patterns that would be predicted by the availability of raw material. Further, it appears that hominin transport decisions involved an assessment of the potential use-life of certain forms. Many aspects of Developed Oldowan technology conform to previously developed models of curated technologies. (C) 2008 Elsevier Ltd. All rights reserved

In this study, patterns of prehistoric trepanation in the southern highlands of Peru were examined through an analysis of 11 Cuzco-region burial sites. Trepanations were found in 66 individuals, with several individuals exhibiting more than one trepanation, for a total of 109 perforations observed. The predominant methods used were circular cutting and scraping-methods that proved highly successful with an overall 83% survival rate and little ensuing infection. Survival rates showed a significant increase over time, apparently reflecting improvements in trepanation technique through experimentation and practical experience. Practitioners avoided certain areas of the cranium and employed methods that reduced the likelihood of damage to the cerebral meninges and venous sinuses. In many cases, trepanation as a medical treatment appears to have been prompted by cranial trauma, a finding that corroborates other studies pointing to cranial trauma as a primary motivation for the surgical procedure.

Reconstruction of early Pleistocene hominin carcass acquisition and processing behaviors are necessarily based at least in part on butchered fossil bones. This paper provides zooarchaeological and taphonomic analyses and behavioral interpretations of three similar to 1.5 million-year-old archaeofaunas from areas 1A and 103 in the Okote Member of the Koobi Fora Formation, northern Kenya: FwJj14A, FwJj14B, and GaJi14. These sites are all located in similar paleoenvironmental contexts, near shallow water with swampy, seasonally flooded areas, and some evidence for more wooded or gallery forest settings. Both individual specimen- and assemblage-level analyses of butchery-marked bones indicate that the hominins appear to have practiced similar butchery strategies at all of these sites, with butchery (defleshing, disarticulation, and marrow extraction) of both high- and low-ranked skeletal elements with no apparent preference for prey size, skeletal region, limb class, or limb portion. Only four tooth-marked specimens, including one likely crocodile-tooth-marked bone, are preserved in all three archaeofaunas. A paucity of limb epiphyses suggests that bone-crunching hyenids may have deleted these portions subsequent to hominin butchery. Strangely, there are no stone tools preserved with the 292 cut-marked and 27 percussion-marked faunal specimens (out of a total of 6,039 specimens), suggesting that raw material availability may have conditioned hominin lithic discard patterns at these locales. These assemblages increase our knowledge of the dietary behavior and ecology of Homo erectus, and provide support for variability in early Pleistocene hominin carcass foraging patterns. (C) 2008 Elsevier Ltd. All rights reserved.

Cranioplasty is a well-known procedure in modern neurosurgery. Although some authors have claimed it was also performed by prehistoric trepanners in various parts of the world, there is little hard evidence to support this. Here we review various claims of cranioplasty in Peru, where trepanation was widely practised in Prehispanic times. We find little support for assertions that cranioplasty was common. One recently discovered burial from the Cuzco region, however, provides the first documented case of the reinsertion of a bone plug into a trepanation opening. Copyright (C) 2008 John Wiley & Sons, Ltd.

This paper is an empirical extension aimed at investigating the relationships between the indicators of the financial superstructure and its intermediation environments; and especially how the former responds to the effects of the latter. Intermediation-environmental models patterned after multivariate regression, causality, and partial adjustment models of both linear and log-linear formulations were estimated and analyzed. The results reveal that three environments: socio-political, regulatory, and international finance-exerted significant effects on the intermediation function of the superstructure. Previous intermediation successes ginger up current performance. In the long run, the effects of the environmental factors on the intermediation function of the superstructure, in whatever direction, more than quadruples. In any given year, the Nigerian financial superstructure attains only about 21.9% of desired (optimal) FIR. Given this, it would take about 4-1/2 years for it to adjust its intermediation operations (FIR), in light of the effects of environmental factors, to optimal levels in order to significantly impact the economy as desired. Some consistent behavioral traits were identified from the results to include: the precepts of potential maximization, profit maximization, accommodation principles, survival and cost-minimization principles, and the neutrality axiom. © 2007 by The Haworth Press, Inc. All rights reserved.