Polyhydroxybutyrate accumulation by a Serratia sp

A strain of Serratia sp. showed intracellular electron-transparent inclusion bodies when incubated in the presence of citrate and glycerol 2-phosphate without nitrogen source following pregrowth under carbon-limitation in continuous culture. About 1.3 mmol citrate were consumed per 450 mg\ud biomass, giving a calculated yield of maximally 55% of stored material per g of biomass dry wt. The inclusion bodies were stained with Sudan Black and Nile Red (NR), suggesting a lipid material, which was confirmed as polyhydroxybutyrate (PHB) by analysis of molecular fragments by GC and by FTIR spectroscopy of isolated bio-PHB in comparison with reference material. Multi-parameter flow cytometry in conjunction with NR fluorescence, and electron microscopy, showed that not all cells contained heavy PHB bodies, suggesting the potential for increasing\ud the overall yield. The economic attractiveness is\ud enhanced by the co-production of nanoscale hydroxyapatite\ud (HA), a possible high-value precursor for bone replacement materials

Valeur socio-économique de l’arbre en milieu malinké (Khossanto, Sénégal)

Objectif: Déterminer la valeur socio-économique des ligneux dans la vie des populations de la communauté rurale de Khossanto, dans la partie orientale du Sénégal et apprécier les savoirs et savoir-faire locaux vis-à-vis de l’arbre.Méthodologie et résultats: Des enquêtes ethnobotaniques ont été menés auprès des populations de la communauté rurale de Khossanto. Nous avons recensé les savoirs et savoir-faire des Malinkés vis-à-vis de l’arbre dans six catégories d’usages : alimentation, fourrage, construction, artisanat, énergie domestique et phytothérapie, avec des niveaux de consensus assez élevés (partout supérieur à 80%). Six espèces multi usages (impliquées dans presque toutes les catégories) s’avèrent être les plus utiles : Cordyla pinnata, Borassus aethiopum, Vitellaria paradoxa, Ziziphus mauritiana, Pterocarpus erinaceus et Adansonia digitata. Les fruits (31%), les feuilles (29%) et le bois (22%) sont les parties les plus utilisées.Conclusion et application des résultats: L’importance socio-économique de l’arbre en milieu malinké est clairement établie autour de six catégories d’usage : le fourrage, l’alimentation humaine, l’énergie domestique, la phytothérapie, la construction et l’artisanat. Cette importance des ligneux a pour corollaire un prélèvement assez intense de certaines parties, qui devient une menace pour ces espèces. Il apparaît important d’asseoir un modèle de gestion durable de ces parcours communautaires.Mots clés : Ligneux, usages, importance, Sénégal , Kédougou

Factorizations of Elements in Noncommutative Rings: A Survey

We survey results on factorizations of non zero-divisors into atoms (irreducible elements) in noncommutative rings. The point of view in this survey is motivated by the commutative theory of non-unique factorizations. Topics covered include unique factorization up to order and similarity, 2-firs, and modular LCM domains, as well as UFRs and UFDs in the sense of Chatters and Jordan and generalizations thereof. We recall arithmetical invariants for the study of non-unique factorizations, and give transfer results for arithmetical invariants in matrix rings, rings of triangular matrices, and classical maximal orders as well as classical hereditary orders in central simple algebras over global fields.Comment: 50 pages, comments welcom

The stability paradox : why expansion of education for women has not delayed age at first union or childbearing in Latin America

Despite substantial improvements in women's education, the age atwhich Latin American women marry (cohabit) or become mothers for the first time has barely decreased over the past four decades. We refer to this as the "stability paradox." We examine the relationship between years of schooling and transitions to first union or child, analyzing retrospective information from 50 cohorts of women born between 1940 and 1989 in 12 Latin American countries. Absolute and relative measures of schooling are compared. Data is drawn from 38 Demographic Health Surveys (DHS) conducted between 1986 and 2012 in these countries. Results show that expected postponement in family transitions due to educational expansion was offset by a rise in union formation and childbearing within strata of absolute education, but stayed approximately constant within strata of relative education. The relative measure of education retains the stratifying power of education but neutralizes any effect attached to a specific number of years of schooling and the learning skills associated with them. This is consistent with the idea that access to education in Latin America reproduces existing patterns of socioeconomic advantage, rather than creating a more equitable distribution of learning opportunities and outcomes

The enigma of Oligocene climate and global surface temperature evolution.

Falling atmospheric CO2 levels led to cooling through the Eocene and the expansion of Antarctic ice sheets close to their modern size near the beginning of the Oligocene, a period of poorly documented climate. Here, we present a record of climate evolution across the entire Oligocene (33.9 to 23.0 Ma) based on TEX86 sea surface temperature (SST) estimates from southwestern Atlantic Deep Sea Drilling Project Site 516 (paleolatitude ∼36°S) and western equatorial Atlantic Ocean Drilling Project Site 929 (paleolatitude ∼0°), combined with a compilation of existing SST records and climate modeling. In this relatively low CO2 Oligocene world (∼300 to 700 ppm), warm climates similar to those of the late Eocene continued with only brief interruptions, while the Antarctic ice sheet waxed and waned. SSTs are spatially heterogenous, but generally support late Oligocene warming coincident with declining atmospheric CO2 This Oligocene warmth, especially at high latitudes, belies a simple relationship between climate and atmospheric CO2 and/or ocean gateways, and is only partially explained by current climate models. Although the dominant climate drivers of this enigmatic Oligocene world remain unclear, our results help fill a gap in understanding past Cenozoic climates and the way long-term climate sensitivity responded to varying background climate states

Preventable cancer mortality in American Indian and Alaska Native women.

This report describes a series of six studies on cancer in American Indian and Alaska Native (AI/AN) women, with a particular emphasis on cancer of the breast and cervix. Data from the Indian Health Service (IHS) inpatient data system was used to generate estimates of incidence of cancer among AI/AN populations. Additionally, breast cancer rates among Indian women in Arizona and New Mexico were compiled from extensive chart review of the New Mexico Tumor Registry and the IHS Inpatient Data System. Study of the performance of the health care system for cancer screening in women suggest that the major deficiency lies not in a failure to bring women in for screening, but rather to complete the screening after contact has been made and the need for screening recognized. The studies indicate that cancer is generally diagnosed in American Indian women at a more advanced stage and survival experience of Indian cancer patients is worse than non-Indian, even when corrected for later stage at diagnosis. Several of the studies suggest that failure to diagnose cancer in its very early stages appears to be in large part dependent on patient behavior. An alarming number of women do not keep follow-up appointments, even after multiple referrals and rescheduling of appointments. These findings suggest the need for intervention strategies that encourage women to become knowledgeable about cancer and to accept responsibility for their screening. The studies suggest that the relative difficulty in improving screening rates are traced to an inadequate understanding of cancer and its prevention on the part of women in the community

Modified Laminar Bone in Ampelosaurus atacis and Other Titanosaurs (Sauropoda): Implications for Life History and Physiology

BACKGROUND: Long bone histology of the most derived Sauropoda, the Titanosauria suggests that titanosaurian long bone histology differs from the uniform bone histology of basal Sauropoda. Here we describe the long bone histology of the titanosaur Ampelosaurus atacis and compare it to that of basal neosauropods and other titanosaurs to clarify if a special titanosaur bone histology exists. METHODOLOGY/PRINCIPAL FINDINGS: Ampelosaurus retains the laminar vascular organization of basal Sauropoda, but throughout most of cortical growth, the scaffolding of the fibrolamellar bone, which usually is laid down as matrix of woven bone, is laid down as parallel-fibered or lamellar bone matrix instead. The remodeling process by secondary osteons is very extensive and overruns the periosteal bone deposition before skeletal maturity is reached. Thus, no EFS is identifiable. Compared to the atypical bone histology of Ampelosaurus, the large titanosaur Alamosaurus shows typical laminar fibrolamellar bone. The titanosaurs Phuwiangosaurus, Lirainosaurus, and Magyarosaurus, although differing in certain features, all show this same low amount or absence of woven bone from the scaffolding of the fibrolamellar bone, indicating a clear reduction in growth rate resulting in a higher bone tissue organization. To describe the peculiar primary cortical bone tissue of Phuwiangosaurus, Ampelosaurus, Lirainosaurus, and Magyarosaurus, we here introduce a new term, "modified laminar bone" (MLB). CONCLUSIONS/SIGNIFICANCE: Importantly, MLB is as yet not known from extant animals. At least in Lirainosaurus and Magyarosaurus the reduction of growth rate indicated by MLB is coupled with a drastic body size reduction and maybe also a reduction in metabolic rate, interpreted as a result of dwarfing on the European islands during the Late Cretaceous. Phuwiangosaurus and Ampelosaurus both show a similar reduction in growth rate but not in body size, possibly indicating also a reduced metabolic rate. The large titanosaur Alamosaurus, on the other hand, retained the plesiomorphic bone histology of basal neosauropods

Selective expression of a VHIV subfamily of immunoglobulin genes in human CD5+ B lymphocytes from cord blood.

Human B lymphocytes expressing the CD5 surface antigen (CD5+ B cells) constitute a subset capable of producing polyspecific antibodies recognizing a variety of self antigens. The repertoire of antibodies produced by CD5+ and CD5- B cells is different. However, it is not yet established whether this distribution is reflected in different immunoglobulin variable region gene (IgV) use. Rearrangement of heavy chain IgV (IgVH) genes represents one of the first identifiable stages in the maturation of B cells, and occurs in a developmentally ordered fashion. The repertoire of IgVH gene expression is highly restricted during fetal life but diversifies progressively after birth. A high frequency of VH gene use from the relatively small VHIV gene family has previously been demonstrated in human fetal liver B cells. In the present study, 102 B cell lines established by Epstein-Barr Virus-transformation of separated CD5+ and CD5- cord blood B cells, were examined for the frequency of IgV expression using monoclonal antibodies to cross-reactive idiotypes (CRI). The results demonstrate a relatively high frequency of VHIV gene use (30%) in B cells from cord blood. Furthermore, two mutually exclusive CRI associated with distinct subgroups of the VHIV family are segregated in their association with either subset of B cells. One CRI is exclusively expressed in lines established from CD5+ B cells while the other is associated with lines established from CD5- B cells

Vascularization of the dorsal root ganglia and peripheral nerve of the mouse: Implications for chemical-induced peripheral sensory neuropathies

Although a variety of industrial chemicals, as well as several chemotherapeutic agents used to treat cancer or HIV, preferentially induce a peripheral sensory neuropathy what remains unclear is why these agents induce a sensory vs. a motor or mixed neuropathy. Previous studies have shown that the endothelial cells that vascularize the dorsal root ganglion (DRG), which houses the primary afferent sensory neurons, are unique in that they have large fenestrations and are permeable to a variety of low and high molecular weight agents. In the present report we used whole-mount preparations, immunohistochemistry, and confocal laser scanning microscopy to show that the cell body-rich area of the L4 mouse DRG has a 7 fold higher density of CD31+ capillaries than cell fiber rich area of the DRG or the distal or proximal aspect of the sciatic nerve. This dense vascularization, coupled with the high permeability of these capillaries, may synergistically contribute, and in part explain, why many potentially neurotoxic agents preferentially accumulate and injure cells within the DRG. Currently, cancer survivors and HIV patients constitute the largest and most rapidly expanding groups that have chemically induced peripheral sensory neuropathy. Understanding the unique aspects of the vascularization of the DRG and closing the endothelial fenestrations of the rich vascular bed of capillaries that vascularize the DRG before intravenous administration of anti-neoplastic or anti-HIV therapies, may offer a mechanism based approach to attenuate these chemically induced peripheral neuropathies in these patients

Holographic dilepton production in a thermalizing plasma

We determine the out-of-equilibrium production rate of dileptons at rest in strongly coupled N=4 Super Yang-Mills plasma using the AdS/CFT correspondence. Thermalization is achieved via the gravitational collapse of a thin shell of matter in AdS_5 space and the subsequent formation of a black hole, which we describe in a quasistatic approximation. Prior to thermalization, the dilepton spectral function is observed to oscillate as a function of frequency, but the amplitude of the oscillations decreases when thermal equilibrium is approached. At the same time, we follow the flow of the quasinormal spectrum of the corresponding U(1) vector field towards its equilibrium limit.Comment: 21 pages, 7 figures. v2: Version accepted for publication in JHEP; minor modifications, added reference