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Kinds of D. Terms modified by D. Selected AbstractsIntermittent exposure to low-concentration paraphenylenediamine can be equivalent to single, higher-dose exposureCONTACT DERMATITIS, Issue 5 2007Jonathan M. L. White Hair dye allergy is an important and increasingly common cause of allergic contact dermatitis. The role of repeated exposure in elicitation of allergy has not previously been extensively studied. We have therefore compared elicitation between single and intermittent exposure to paraphenylenediamine (PPD). 23 subjects known to be allergic to PPD from positive patch tests were exposed to 0.3% and 0.03% PPD, both in petrolatum and water, for 5 min at the same site every day for up to 8 D. In the same subjects, single exposures were also performed at different sites, from 5 to 40 min. Other experiments exposed rat skin to radiolabelled PPD as one-off application or multiple exposures. There were 8 reactions in the cumulative exposure site using 0.3% PPD in aqueous solution. In 7 of these, there was an exact correlation with reaction to the cumulative time needed for repeat exposures to elicit a reaction and the time needed for a reaction to the single exposure. There were no reactions to 0.03% PPD in water or pet under either type of exposure condition. There was also a positive correlation between grade of original reaction in clinic (+++, ++, +) and appearance/intensity of elicitation reactions. In the animal study, cumulative time and single exposure time sites correlated with regards to retention of radiolabelled substance within the skin. This study therefore demonstrates for the first time that, over the time period tested, the allergenic component of PPD accumulates in the skin. Hence, intermittent exposure to lower concentrations of PPD may be equivalent to higher concentration, one-off exposure. [source] Configuration, conformation and crystal structure of rabdosianin bCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005Bao Lin Li Abstract Rabdosianin B, 7,20-epoxy-7,-hydroxy-1,,6,,11,,15,-tetraacetoxy- ent -kaur-16-ene, C28H38O10, was the first isolated from Isodon henryi. It consists of three six-membered rings A, B, C and one five-membered ring D. The fused-ring system A, B and C are in chair, boat and chair conformations, respectively, and ring D is in an envelope conformation, on the basis of NMR and X-ray diffraction analysis. The crystal of rabdosianin B is in orthorhombic crystal system with space group P212121, lattice constants: a = 9.969(1) Å, b = 15.400(3) Å, and c = 17.624(3) Å, Z = 4. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Compaction of cell shape occurs before decrease of elasticity in CHO-K1 cells treated with actin cytoskeleton disrupting drug cytochalasin DCYTOSKELETON, Issue 4 2009Christian Schulze Abstract The actin filaments of the cytoskeleton form a highly dynamic polymer scaffold which is actively involved in many essential mechanisms such as cell migration, transport, mitosis, and mechanosensitivity. We treated CHO-K1 cells with different concentrations of the actin cytoskeleton disrupting drug cytochalasin D. Then investigating the cells' elastic behaviour by scanning force microscopy-based rheology we confirmed for high cytochalasin D concentrations (,1.5 ,M) a significant decrease of mechanical stability. At lower concentrations we measured no significant softening, but flattening and a horizontal contraction was observable even at low concentrations (,0.3 ,M) of cytochalasin D. The observed changes in cell shape resulted in a lower cell volume, showing that there is compensation by volume for small decreases in cytoskeletal strength resulting from reduced numbers or lengths of actin filaments. These results suggest that the characteristic functions defining a cell's mechanical stability such as mechanosensitivity can be maintained via small changes in cell volume in order to counter fluctuations in cytoskeletal composition. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Divergent roles of the DEAD-box protein BS-PL10, the urochordate homologue of human DDX3 and DDX3Y proteins, in colony astogeny and ontogenyDEVELOPMENTAL DYNAMICS, Issue 6 2006Amalia Rosner Abstract Proteins of the highly conserved PL-10 (Ded1P) subfamily of DEAD-box family, participate in a wide variety of biological functions. However, the entire spectrum of their functions in both vertebrates and invertebrates is still unknown. Here, we isolated the Botryllus schlosseri (Urochordata) homologue, BS-PL10, revealing its distributions and functions in ontogeny and colony astogeny. In botryllid ascidians, the colony grows by increasing the number of modular units (each called a zooid) through a whole colony synchronized and weekly cyclical astogenic budding process (blastogenesis). At the level of the colony, both BS-PL10 mRNA and its protein (78 kDa) fluctuate in a weekly pattern that corresponds with the animal's blastogenic cycle, increasing from blastogenic stage A to blastogenic stage D. At the organ/module level, a sharp decline is revealed. Primary and secondary developing buds express high levels of BS-PL10 mRNA and protein at all blastogeneic stages. These levels are reduced four to nine times in the new set of functional zooids. This portrait of colony astogeny differed from its ontogeny. Oocytes and sperm cells express high levels of BS-PL10 protein only at early stages of development. Young embryos reveal background levels with increased expressions in some organs at more developed stages. Results reveal that higher levels of BS-PL10 mRNA and protein are characteristic to multipotent soma and germ cells, but patterns deviate between two populations of differentiating stem cells, the stem cells involved in weekly blastogenesis and stem cells involved in embryogenesis. Two types of experimental manipulations, zooidectomy and siRNA assays, have confirmed the importance of BS-PL10 for cell differentiation and organogenesis. BS-PL10 (phylogenetically matching the animal's position in the evolutionary tree), is the only member of this subfamily in B. schlosseri, featuring a wide range of biological activities, some of which represent pivotal roles. The surprising weekly cyclical expression and the participation in cell differentiation posit this molecule as a model system for studying PL10 protein subfamily. Developmental Dynamics 235:1508,1521, 2006. © 2006 Wiley-Liss, Inc. [source] Grasshopper (Orthoptera: Acridoidea) species diversity in the Pampas, ArgentinaDIVERSITY AND DISTRIBUTIONS, Issue 2 2000María Marta Cigliano Abstract., A study was conducted to describe the major features of geographical and temporal variation in the diversity of grassland grasshopper species (Orthoptera: Acridoidea) in different sites of the Pampas, Argentina. Species richness and relative abundance were assessed at 12 sites in eastern La Pampa and western Buenos Aires provinces, from 1994 through 1999. Mean species richness at the regional level was 10, and 34 grasshopper species were collected throughout of the study. Comparison with grasshopper species diversity from the Great Plains of North America is discussed. An evaluation of the proportions of species in each of the three distribution groups (broad, intermediate and narrow) revealed that, over all sites, broadly distributed species made up 14.7% of species composition and intermediately and narrowly distributed species made up 26.5% and 58.8%, respectively. The three top-ranked species in the studied sites were Dichroplus elongatus, D. pratensis and Staurorhectus longicornis. Results showed that, contrary to what was expected, one of the widely distributed species in the region (i.e. Baeacris punctulatus) does not always constitute one of the most abundant species. Finally, the loss of one of the historically most common species in the Pampas, D. maculipennis, is also discussed. [source] Functional morphology of the postpharyngeal gland of queens and workers of the ant Monomorium pharaonis (L.)ACTA ZOOLOGICA, Issue 2 2006Dieter Eelen Abstract Eelen D., Børgesen L.W. and Billen J. 2006. Functional morphology of the postpharyngeal gland of queens and workers of the ant Monomorium pharaonis (L.). ,Acta Zoologica (Stockholm) 87: 101,111 The postpharyngeal gland (PPG) is unique to ants and is the largest exocrine gland in their head. In queens of the pharaoh's ant, Monomorium pharaonis, the gland contains approximately 15 finger-like epithelial extensions on each side and opens dorsolaterally in the posterior pharynx. In these ants the PPG morphology varies considerably according to age and mating status. The epithelial thickness increases with age and reaches a maximum at 3 weeks in both virgin and mated queens. A considerable expansion of the lumen diameter occurs in both groups between 4 and 7 days. Virgin queens release their secretion into the gland lumen from an age of 7 days, whereas mated queens accumulate large amounts of secretion in their epithelium. The increasing epithelial thickness, together with the increasing lumen diameter, the presence of numerous inclusions in the epithelium and the release of secretion, are indicative for increasing gland activity. The gland ultrastructure indicates involvement in lipid metabolism and de novo synthesis of lipids. The PPG of workers consists of 12 finger-like tubes at each side. There is a significant difference in epithelial thickness between nurses and repletes and between nurses and foragers. We suggest the PPG serves different purposes in pharaoh's ants: it is likely that the PPG of workers and virgin queens is used to feed larvae. In mated queens the gland probably plays a role in providing the queen with nutritious oils for egg production. The PPG may also function in signalling species nestmate and caste identity, as well as in the reproductive capacity of the queens. [source] The male postabdomen of Stolotermes inopinus: a termite with unusually well-developed external genitalia (Dictyoptera: Isoptera: Stolotermitinae)ACTA ZOOLOGICA, Issue 2 2000Klaus-Dieter Klass Abstract Klass, K.-D., Thorne, B. L. and Lenz, M. 2000. The male postabdomen of Stolotermes inopinus: a termite with unusually well-developed external genitalia (Dictyoptera: Isoptera: Stolotermitinae). ,Acta Zoologica (Stockholm) 81: 121,130 Stolotermes inopinus has large external male genitalia (phallic lobe), which contrast with the small genital papillae or lack of external genitalia of other Isoptera. As in the genital papilla of Mastotermesdarwiniensis, a ventral sclerite pair is present, the gonopore is located ventroterminally on the phallic lobe, and the genital area is entirely symmetrical , suggesting that this may be the groundplan condition of Isoptera. The relations of the phallic lobe to surrounding components like the subgenital plate, paraprocts, and certain muscles and nerves indicate that the lobe of S. inopinus is homologous with the phallomeres of other Dictyoptera. The bilateral symmetry and simple structure, however, are in strong contrast to the asymmetry and high complexity found in male genitalia of Blattaria and Mantodea. The postabdominal nervous system of S. inopinus resembles that of the cockroach Periplaneta americana. Indications are given that the Stolotermitinae are related to the Kalotermitidae, Rhinotermitidae, and Termitidae rather than to the Termopsinae. [source] Taxonomic revision of the genus Dolophilodes subgenus Dolophilodes (Trichoptera: Philopotamidae) of JapanENTOMOLOGICAL SCIENCE, Issue 1 2005Naotoshi KUHARA Abstract Japanese species of the genus Dolophilodes subgenus Dolophilodes are revised taxonomically. Seven described species are recognized: D. japonicus (Banks), D. shinboensis (Kobayashi), D. auriculatus Martynov, D. nomugiensis (Kobayashi), D. babai (Kobayashi), D. iroensis (Kobayashi) and D. commatus (Kobayashi). In addition, two new species, D. angustatus and D. dilatatus, are described. Males of all nine species and females of all but D. babai are described and illustrated. The subgenus Hisaura Kobayashi is synonymized under the subgenus Dolophilodes. Three synonymies of species proposed are Wormaldia triangulata Kobayashi under D. nomugiensis, D. kunashirensis Ivanov under D. iroensis and Sortosa kaishoensis Kobayashi under D. commatus. [source] Evolution of a chlorobenzene degradative pathway among bacteria in a contaminated groundwater mediated by a genomic island in RalstoniaENVIRONMENTAL MICROBIOLOGY, Issue 3 2003Tina Andrea Müller Summary The genetic structure of two Ralstonia spp., strain JS705 and strain JS745, isolated from the same groundwater aquifer, was characterized with respect to the degradation capacities for toluene and chlorobenzene degradation. Cosmid library construction, cloning, DNA sequencing and mating experiments indicated that the genes for chlorobenzene degradation in strain JS705 were a mosaic of the clc genes, previously described for Pseudomonas sp. strain B13, and a 5 kb fragment identical to strain JS745. The 5 kb fragment identical to both JS705 and JS745 was flanked in JS705 by one complete and one incomplete insertion (IS) element. This suggested involvement of the IS element in mobilizing the genes from JS745 to JS705, although insertional activity of the IS element in its present configuration could not be demonstrated. The complete genetic structure for chlorobenzene degradation in strain JS705 resided on a genomic island very similar to the clc element (Ravatn, R., Studer, S., Springael, D., Zehnder, A.J., van der Meer, J.R. 1998. Chromosomal integration, tandem amplification, and deamplification in Pseudomonas putida F1 of a 105-kilobase genetic element containing the chlorocatechol degradative genes from Pseudomonas sp. strain B13. J Bacteriol 180: 4360,4369). The unique reconstruction of formation of a metabolic pathway through the activity of IS elements and a genomic island in the chlorobenzene-degrading strain JS705 demonstrated how pathway evolution can occur under natural conditions in a few ,steps'. [source] Erratum: Analysis of the effects of ultrafine particulate matter while accounting for human exposureENVIRONMETRICS, Issue 6 2009Brian J. Reich Volume 20, Issue 2, Pages 131,146 (March 2009) DOI: 10.1002/env.915 On page 144 of the above paper, under Discussion, the first sentence of the third paragraph should read, "The dynamic factor model proposed in Section 3 could be adapted to model a single pollutant that is repeatedly measured at multiple locations, as in Lopes et al. (2008).". The additional reference is: Lopes, H., Salazar, E. and Gamerman, D. 2008. Spatial dynamic factor analysis. Bayesian Analysis3: 759,792. [source] A model of treatment decision making when patients have advanced cancer: how do cancer treatment doctors and nurses contribute to the process?EUROPEAN JOURNAL OF CANCER CARE, Issue 4 2010L. MCCULLOUGH msc, nurse leader clinical support services MCCULLOUGH L., MCKINLAY E., BARTHOW C., MOSS C. & WISE D. (2010) European Journal of Cancer Care A model of treatment decision making when patients have advanced cancer: how do cancer treatment doctors and nurses contribute to the process? This qualitative study describes how doctors and nurses report their contribution to treatment decision-making processes when patients have advanced cancer. Thirteen nurses and eight doctors involved in cancer treatment and palliation in one geographical location in New Zealand participated in the study. Data were collected using qualitative in-depth, face-to-face interviews. Content analysis revealed a complex context of decision making influenced by doctors and nurses as well as the patient and other factors. A model of clinician and patient decision making emerged with a distinct and cyclical process as advanced cancer remits and progresses. When patients have advanced cancer, nurses and doctors describe a predictable model of decision making in which they both contribute and that cycles through short- and long-term remissions; often nowadays to the point of the patient dying. In conclusion, the findings suggest doctors and nurses have different but complementary roles in what, when and how treatment choices are negotiated with patients, nevertheless within a distinct model of decision making. [source] Complementary and alternative medicine practitioner consultations among those who have or have had cancer in a Norwegian total population (Nord-Trøndelag Health Study): prevalence, socio-demographics and health perceptionsEUROPEAN JOURNAL OF CANCER CARE, Issue 3 2010A. STEINSBEKK phd, research fellow STEINSBEKK A., ADAMS J., SIBBRITT D. & JOHNSEN R. (2010) European Journal of Cancer Care19, 346,351 Complementary and alternative medicine practitioner consultations among those who have or have had cancer in a Norwegian total population (Nord-Trøndelag Health Study): prevalence, socio-demographics and health perceptions The aim of the study was to identify the use of complementary and alternative medicine (CAM) practitioners among current and previous cancer patients in a total population. A secondary analysis of data from the Nord-Trøndelag Health Study (otherwise known as the HUNT 2 Study) , a total population survey conducted in central Norway , was undertaken. Analysis focused upon the response of 1406 individuals who reported to have or have had cancer and who answered a question on visits to CAM practitioners. The study identified 16.1% of respondents had visited a CAM practitioner in the prior 12 months compared with 12.8% in the total population, and the likelihood of consulting a CAM practitioner was significantly increased among those who had a university degree, who reported a lower perceived global health and who had experienced a health complaint during the last 12 months. Complementary and alternative medicine practitioner consultations among individuals with a previous or current malignant disease were highest for those with poor self-reported health status and with a recent health complaint. From the socio-demographic variables studied only the reporting of a university degree was significantly associated with higher CAM practitioner use. [source] Care of the older woman with primary breast cancer: a sign of the times?EUROPEAN JOURNAL OF CANCER CARE, Issue 6 2009D. POROCK rn, professor POROCK D., CHEUNG, K.L., MORGAN D.A.L., WINTERBOTTOM L., RICHARDSON H. & ELLIS I.O. (2009) European Journal of Cancer Care18, 527,529 Care of the older woman with primary breast cancer: a sign of the times? [source] Variability of IgE reactivity profiles among European mite allergic patientsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2008M. Weghofer Abstract Background, House dust mites (HDM) Dermatophagoides pteronyssinus are a frequent indoor allergen source. Our aim was to determine the frequencies of IgE reactivity to purified HDM allergen molecules in mite allergic patients from different parts of Europe in order to establish an allergen panel for diagnosis of HDM allergy. Materials and methods, Populations of D. pteronyssinus -allergic patients from Austria (n = 56), France (n = 55), Italy (n = 67) and Sweden (n = 65) and storage mite allergic patients from Sweden (n = 31) were analysed for IgE reactivity to eight purified natural (n) and recombinant (r) D. pteronyssinus allergens (nDer p 1, rDer p 2, nDer p 4, rDer p 5, rDer p 7, rDer p 8, rDer p 10 and rDer p 14) in RAST-based dot blot assays. Results, Using a combination of Der p 1 and Der p 2, at least 97% of the D. pteronyssinus -allergic patients could be diagnosed in each of the HDM allergic populations. However, more than 50% of the patients also reacted with other allergens and significant variabilities regarding the frequencies of IgE reactivity to individual allergen molecules were found. Patients with a predominant storage mite allergy showed none or only very weak IgE reactivity to purified D. pteronyssinus allergens. Conclusions, Purified Der p 1 and Der p 2 are sufficient for the diagnosis of , 97% of D. pteronyssinus allergic patients in Europe, but other allergens may also play an important role for the diagnosis and treatment of HDM allergy. [source] Books and Materials ReviewsFAMILY RELATIONS, Issue 4 2001Article first published online: 19 FEB 200 Baumeister, R. F. (Ed.). (1999). The Self in Social Psychology. Carter, B., & McGoldrick, M. (1999). The Expanded Family Life Cycle: Individual, Family, and Social Perspectives. Dwyer, D. (2000). Interpersonal Relationships. Knauer, S. (2000). No Ordinary Life: Parenting the Sexually Abused Child and Adolescent. McNair-Blatt, S. (2000). A Guidebook for Raising Foster Children. Stafford-Upshaw, F., & Myers-Walls, J. A. (1999). Learning Centers in Child Care Settings. Seymour, S. C. (1999). Women, Family and Child Care in India: A World in Transition. Berger, R. (1998). Stepfamilies: A Multi-Dimensional Perspective. [source] Insights into the structure of plant ,-type phospholipase DFEBS JOURNAL, Issue 10 2007Susanne Stumpe Phospholipases D play an important role in the regulation of cellular processes in plants and mammals. Moreover, they are an essential tool in the synthesis of phospholipids and phospholipid analogs. Knowledge of phospholipase D structures, however, is widely restricted to sequence data. The only known tertiary structure of a microbial phospholipase D cannot be generalized to eukaryotic phospholipases D. In this study, the isoenzyme form of phospholipase D from white cabbage (PLD,2), which is the most widely used plant phospholipase D in biocatalytic applications, has been characterized by small-angle X-ray scattering, UV-absorption, CD and fluorescence spectroscopy to yield the first insights into its secondary and tertiary structure. The structural model derived from small-angle X-ray scattering measurements reveals a barrel-shaped monomer with loosely structured tops. The far-UV CD-spectroscopic data indicate the presence of ,-helical as well as ,-structural elements, with the latter being dominant. The fluorescence and near-UV CD spectra point to tight packing of the aromatic residues in the core of the protein. From the near-UV CD signals and activity data as a function of the calcium ion concentration, two binding events characterized by dissociation constants in the ranges of 0.1 mm and 10,20 mm can be confirmed. The stability of PLD,2 proved to be substantially reduced in the presence of calcium ions, with salt-induced aggregation being the main reason for irreversible inactivation. [source] Proteolytic activation of internalized cholera toxin within hepatic endosomes by cathepsin DFEBS JOURNAL, Issue 17 2005Clémence Merlen We have defined the in vivo and in vitro metabolic fate of internalized cholera toxin (CT) in the endosomal apparatus of rat liver. In vivo, CT was internalized and accumulated in endosomes where it underwent degradation in a pH-dependent manner. In vitro proteolysis of CT using an endosomal lysate required an acidic pH and was sensitive to pepstatin A, an inhibitor of aspartic acid proteases. By nondenaturating immunoprecipitation, the acidic CT-degrading activity was attributed to the luminal form of endosomal cathepsin D. The rate of toxin hydrolysis using an endosomal lysate or pure cathepsin D was found to be high for native CT and free CT-B subunit, and low for free CT-A subunit. On the basis of IC50 values, competition studies revealed that CT-A and CT-B subunits share a common binding site on the cathepsin D enzyme, with native CT and free CT-B subunit displaying the highest affinity for the protease. By immunofluorescence, partial colocalization of internalized CT with cathepsin D was confirmed at early times of endocytosis in both hepatoma HepG2 and intestinal Caco-2 cells. Hydrolysates of CT generated at low pH by bovine cathepsin D displayed ADP-ribosyltransferase activity towards exogenous Gs, protein suggesting that CT cytotoxicity, at least in part, may be related to proteolytic events within endocytic vesicles. Together, these data identify the endocytic apparatus as a critical subcellular site for the accumulation and proteolytic degradation of endocytosed CT, and define endosomal cathepsin D an enzyme potentially responsible for CT cytotoxic activation. [source] Development of recombinant inhibitors specific to human kallikrein 2 using phage-display selected substratesFEBS JOURNAL, Issue 3 2004Sylvain M. Cloutier The reactive site loop of serpins undoubtedly defines in part their ability to inhibit a particular enzyme. Exchanges in the reactive loop of serpins might reassign the targets and modify the serpin,protease interaction kinetics. Based on this concept, we have developed a procedure to change the specificity of known serpins. First, reactive loops are very good substrates for the target enzymes. Therefore, we have used the phage-display technology to select from a pentapeptide phage library the best substrates for the human prostate kallikrein hK2 [Cloutier, S.M., Chagas, J.R., Mach, J.P., Gygi, C.M., Leisinger, H.J. & Deperthes, D. (2002) Eur. J. Biochem. 269, 2747,2754]. Selected substrates were then transplanted into the reactive site loop of ,1-antichymotrypsin to generate new variants of this serpin, able to inhibit the serine protease. Thus, we have developed some highly specific ,1-antichymotrypsin variants toward human kallikrein 2 which also show high reactivity. These inhibitors might be useful to help elucidate the importance of hK2 in prostate cancer progression. [source] The relationship between thermal stability and pH optimum studied with wild-type and mutant Trichoderma reesei cellobiohydrolase Cel7AFEBS JOURNAL, Issue 5 2003Harry Boer The major cellulase secreted by the filamentous fungus Trichoderma reesei is cellobiohydrolase Cel7A. Its three-dimensional structure has been solved and various mutant enzymes produced. In order to study the potential use of T. reesei Cel7A in the alkaline pH range, the thermal stability of Cel7A was studied as a function of pH with the wild-type and two mutant enzymes using different spectroscopic methods. Tryptophan fluorescence and CD measurements of the wild-type enzyme show an optimal thermostability between pH 3.5,5.6 (Tm, 62 ± 2 °C), at which the highest enzymatic activity is also observed, and a gradual decrease in the stability at more alkaline pH values. A soluble substrate, cellotetraose, was shown to stabilize the protein fold both at optimal and alkaline pH. In addition, unfolding of the Cel7A enzyme and the release of the substrate seem to coincide at both acidic and alkaline pH, demonstrated by a change in the fluorescence emission maximum. CD measurements were used to show that the five point mutations (E223S/A224H/L225V/T226A/D262G) that together result in a more alkaline pH optimum [Becker, D., Braet, C., Brumer, H., III, Claeyssens, M., Divne, C., Fagerström, R.B., Harris, M., Jones, T.A., Kleywegt, G.J., Koivula, A., et al. (2001) Biochem. J.356, 19,30], destabilize the protein fold both at acidic and alkaline pH when compared with the wild-type enzyme. In addition, an interesting time-dependent fluorescence change, which was not observed by CD, was detected for the pH mutant. Our data show that in order to engineer more alkaline pH cellulases, a combination of mutations should be found, which both shift the pH optimum and at the same time improve the thermal stability at alkaline pH range. [source] Microstructures: Facile Fabrication of Monolithic 3D Porous Silica Microstructures and a Microfluidic System Embedded with the Microstructure (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 9 2010Mater. D.-P. Kim and co-workers present the fabrication of monolithic 3D porous silica structures into a multilayer framework with bimodal pore size distribution on page 1473. The structure becomes monolithic upon pyrolyzing the stacked layers, and then easily embedded in microchannel with the aid of photolithography, leading to a microfluidic system with built-in microstructure in a site- and shape-controlled manner. [source] The variation of antioxidant activities and chemical composition of essential oils of Teucrium orientale L. var. orientale during harvesting stagesFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2004Ali Yildirim Abstract The aerial parts of Teucrium orientale L. var. orientale were collected at the budding, ,owering and vegetative stages. In the each stage, essential oils were obtained by hydrodistillation and steam distillation. The chemical compositions of the essential oils were analysed by GC and GC,MS; 43 different compounds were determined in total, and more than 96% of the essential oils were identi,ed by GC and GC,MS. They contain mainly linalool, , -caryophyllene, 3-octanol, phytol, , -bourbonene and germacrene D. Among the steam distillation oils, the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was found at the budding stage and the lowest at the vegetative stage. At all stages, the DPPH radical scavenging activities of hydrodistillation oils were markedly lower than those of steam distillation oils. Steam distillation oils of the budding and ,owering stages showed the highest antioxidant activities. However, steam distillation oils of the vegetative stage in two doses (200 and 400 µg) did not show antioxidant activities (p > 0.05, between these and control). None of the hydrodistillation oils showed detectable antioxidant activity. In contrast, in the presence of 400 µg hydrodistillation oils of ,owering stage, prooxidant activity was found in the linoleic acid emulsion. Copyright © 2004 John Wiley & Sons, Ltd. [source] Feeding rates, assimilation efficiencies and growth of two amphipod species on biodeposited material from zebra musselsFRESHWATER BIOLOGY, Issue 12 2008RENÉ GERGS Summary 1. Accumulation of organic material by the zebra mussel Dreissena polymorpha is assumed to be the source of a biodeposition-based food web. However, only little is known about the importance of the biodeposited material as a food source and its contribution to increased abundances of macroinvertebrates in the presence of D. polymorpha. 2. Feeding, assimilation and growth of the amphipods Gammarus roeselii and Dikerogammarus villosus on food sources directly and indirectly associated with D. polymorpha (biodeposited material and chironomids) and on conditioned alder leaves were measured. The stoichiometry of carbon, nitrogen and phosphorus of the diets was measured as an important determining factor of food quality. 3. Chironomids had the highest nitrogen and phosphorus contents, alder leaves were depleted in nitrogen and phosphorus, and the stoichiometry of biodeposited material was intermediate. 4. Both amphipod species had highest feeding rates and assimilation efficiencies on chironomids. Gammarus roeselii fed more on biodeposited material than on alder leaves, but assimilation efficiencies were similar; D. villosus also had similar feeding rates and assimilation efficiencies on the two diets. 5. Both amphipod species had highest growth rates on chironomids and lowest growth rates on alder leaves. Both grew at intermediate rates on biodeposited material of D. polymorpha. The growth rates of the amphipod species were related to food stoichiometry. Overall, the invasive D. villosus grew faster than the indigenous G. roeselii. 6. Food resources directly and indirectly associated with D. polymorpha are potential diets for amphipods, providing further evidence for a D. polymorpha biodeposition-based food web. [source] The Ohalo II prehistoric camp (19.5 Ky): New evidence for environmental and tectonic changes at the Sea of GalileeGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 5 2002Shmuel Belitzky Combined archaeological data, shore surveys, and aerial photos of submerged sediments in the Sea of Galilee provide new insights into environmental and tectonic events, their dating, and their impact on the Ohalo II prehistoric camp (ca. 19,500 yr B.P.) and its surroundings. The Ohalo II waterlogged campsite contains excellently preserved brush hut remains and other in situ features, all embedded in late Pleistocene lacustrine strata. The findings indicate relatively short occupation of the site, not more than months or several years at a time. The high quality in situ preservation of delicate organic materials, as well as the short occupation period, suggests a quick and gentle burial by fine sediments. The evident fast submergence (water level rise of the Sea of Galilee) could have been the result of climatic fluctuations towards the end of the last glaciation and/or small-scale tectonic subsidence. The site is located on a tectonic block formed in the western fault belt of the Dead Sea Rift. We present new evidence of post-occupational folding of the late Pleistocene strata and recent tilting and faulting. A westward tectonic tilt may have caused the blockage of the old Jordan River outlet after A. D. 1106. Excellent preservation of the fault traces to the east of the site is attributed to the young age of the displacement on the fault. The last displacement apparently post-dates the blockage of the old Jordan River. © 2002 Wiley Periodicals, Inc. [source] Teaching and Learning Guide for: The Geopolitics of Climate ChangeGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Jon Barnett Author's Introduction Climate change is a security problem in as much as the kinds of environmental changes that may result pose risks to peace and development. However, responsibilities for the causes of climate change, vulnerability to its effects, and capacity to solve the problem, are not equally distributed between countries, classes and cultures. There is no uniformity in the geopolitics of climate change, and this impedes solutions. Author Recommends 1.,Adger, W. N., et al. (eds) (2006). Fairness in adaptation to climate change. Cambridge, MA: MIT Press. A comprehensive collection of articles on the justice dimensions of adaptation to climate change. Chapters discuss potential points at which climate change becomes ,dangerous', the issue of adaptation under the United Nations Framework Convention on Climate Change (UNFCCC), the unequal outcomes of adaptation within a society, the effects of violent conflict on adaptation, the costs of adaptation, and examples from Bangladesh, Tanzania, Botswana, and Hungary. 2.,Leichenko, R., and O'Brien, K. (2008). Environmental change and globalization: double exposures. New York: Oxford University Press. This book uses examples from around the world to show the way global economic and political processes interact with environmental changes to create unequal outcomes within and across societies. A very clear demonstration of the way vulnerability to environmental change is as much driven by social processes as environmental ones, and how solutions lie within the realm of decisions about ,development' and ,environment'. 3.,Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. doi:10.1016/j.polgeo.2007.06.003 An up-to-date, systematic and balanced review of research on the links between climate change and violent conflict. See also the other papers in this special issue of Political Geography. 4.,Parry, M., et al. (eds) (2007). Climate change 2007: impacts adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press. The definitive review of all the peer-reviewed research on the way climate change may impact on places and sectors across the world. Includes chapters on ecosystems, health, human settlements, primary industries, water resources, and the major regions of the world. All chapters are available online at http://www.ipcc.ch/ipccreports/ar4-wg2.htm 5.,Salehyan, I. (2008). From climate change to conflict? No consensus yet. Journal of Peace Research 45 (3), pp. 315,326. doi:10.1177/0022343308088812 A balanced review of research on the links between climate change and conflict, with attention to existing evidence. 6.,Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. Gives insight into how the US security policy community is framing the problem of climate change. This needs to be read critically. Available at http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 7.,German Advisory Council on Global Change. (2007). World in transition: climate change as a security risk. Berlin, Germany: WBGU. A major report from the German Advisory Council on Global Change on the risks climate changes poses to peace and stability. Needs to be read with caution. Summary and background studies are available online at http://www.wbgu.de/wbgu_jg2007_engl.html 8.,Yamin, F., and Depedge, J. (2004). The International climate change regime: a guide to rules, institutions and procedures. Cambridge, UK: Cambridge University Press. A clear and very detailed explanation of the UNFCCC's objectives, actors, history, and challenges. A must read for anyone seeking to understand the UNFCCC process, written by two scholars with practical experience in negotiations. Online Materials 1.,Environmental Change and Security Program at the Woodrow Wilson International Center for Scholars http://www.wilsoncenter.org/ecsp The major website for information about environmental security. From here, you can download many reports and studies, including the Environmental Change and Security Project Report. 2.,Global Environmental Change and Human Security Project http://www.gechs.org This website is a clearing house for work and events on environmental change and human security. 3.,Intergovernmental Panel on Climate Change (IPCC) http://www.ipcc.ch/ From this website, you can download all the chapters of all the IPCC's reports, including its comprehensive and highly influential assessment reports, the most recent of which was published in 2007. The IPCC were awarded of the Nobel Peace Prize ,for their efforts to build up and disseminate greater knowledge about man-made (sic) climate change, and to lay the foundations for the measures that are needed to counteract such change'. 4.,Tyndall Centre for Climate Change Research http://www.tyndall.ac.uk The website of a major centre for research on climate change, and probably the world's leading centre for social science based analysis of climate change. From this site, you can download many publications about mitigation of and adaptation to climate change, and about various issues in the UNFCCC. 5.,United Nations Framework Convention on Climate Change http://unfccc.int/ The website contains every major document relation to the UNFCCC and its Kyoto Protocol, including the text of the agreements, national communications, country submissions, negotiated outcomes, and background documents about most key issues. Sample Syllabus: The Geopolitics of Climate Change topics for lecture and discussion Week I: Introduction Barnett, J. (2007). The geopolitics of climate change. Geography Compass 1 (6), pp. 1361,1375. United Nations Secretary General, Kofi Annan, address to the 12th Conference of Parties to the United Nations Framework Convention on Climate Change, Nairobi, 15 November 2006. Available online at http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=495&ArticleID=5424&l=en Week II: The History and Geography of Greenhouse Gas Emissions Topic: The drivers of climate change in space and time Reading Baer, P. (2006). Adaptation: who pays whom? In: Adger, N., et al. (eds) Fairness in adaptation to climate change. Cambridge, MA: MIT Press, pp. 131,154. Boyden, S., and Dovers, S. (1992). Natural-resource consumption and its environmental impacts in the Western World: impacts of increasing per capita consumption. Ambio 21 (1), pp. 63,69. Week III: The Environmental Consequences of climate change Topic: The risks climate change poses to environmental systems Reading Intergovernmental Panel on Climate Change. (2007). Climate change 2007: climate change impacts, adaptation and vulnerability: summary for policymakers. Geneva, Switzerland: IPCC Secretariat. Watch: Al Gore. The Inconvenient Truth. Weeks IV and V: The Social Consequences of Climate Change Topic: The risks climate change poses to social systems Reading Adger, W. N. (1999). Social vulnerability to climate change and extremes in coastal Vietnam. World Development 27, pp. 249,269. Comrie, A. (2007). Climate change and human health. Geography Compass 1 (3), pp. 325,339. Leary, N., et al. (2006). For whom the bell tolls: vulnerability in a changing climate. A Synthesis from the AIACC project, AIACC Working Paper No. 21, International START Secretariat, Florida. Stern, N. (2007). Economics of climate change: the Stern review. Cambridge, UK: Cambridge University Press (Chapters 3,5). Week VI: Mitigation of Climate Change: The UNFCCC Topic: The UNFCCC and the Kyoto Protocol Reading Najam, A., Huq, S., and Sokona, Y. (2003). Climate negotiations beyond Kyoto: developing countries concerns and interests. Climate Policy 3 (3), pp. 221,231. UNFCCC Secretariat. (2005). Caring for climate: a guide to the climate change convention and the Kyoto Protocol. Bonn, Germany: UN Framework Convention on Climate Change Secretariat. Weeks VII and VIII: Adaptation to Climate Change Topic: What can be done to allow societies to adapt to avoid climate impacts? Reading Adger, N., et al. (2007). Assessment of adaptation practices, options, constraints and capacity. In: Parry, M., et al. (eds) Climate change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the intergovernmental panel on climate change. Cambridge, UK: Cambridge University Press, pp. 717,744. Burton, I., et al. (2002). From impacts assessment to adaptation priorities: the shaping of adaptation policy. Climate Policy 2 (2,3), pp. 145,159. Eakin, H., and Lemos, M. C. (2006). Adaptation and the state: Latin America and the challenge of capacity-building under globalization. Global Environmental Change: Human and Policy Dimensions 16 (1), pp. 7,18. Ziervogel, G., Bharwani, S., and Downing, T. (2006). Adapting to climate variability: pumpkins, people and policy. Natural Resources Forum 30, pp. 294,305. Weeks IX and X: Climate Change and Migration Topic: Will climate change force migration? Readings Gaim, K. (1997). Environmental causes and impact of refugee movements: a critique of the current debate. Disasters 21 (1), pp. 20,38. McLeman, R., and Smit, B. (2006). Migration as adaptation to climate change. Climatic Change 76 (1), pp. 31,53. Myers, N. (2002). Environmental refugees: a growing phenomenon of the 21st century. Philosophical Transactions of the Royal Society 357 (1420), pp. 609,613. Perch-Nielsen, S., Bättig, M., and Imboden, D. (2008). Exploring the link between climate change and migration. Climatic Change (online first, forthcoming); doi:10.1007/s10584-008-9416-y Weeks XI and XII: Climate Change and Violent Conflict Topic: Will Climate change cause violent conflict? Readings Barnett, J., and Adger, N. (2007). Climate change, human security and violent conflict. Political Geography 26 (6), pp. 639,655. Centre for Strategic and International Studies. (2007). The age of consequences: the foreign policy and national security implications of global climate change. Washington, DC: CSIS. Nordås, R., and Gleditsch, N. (2007). Climate conflict: common sense or nonsense? Political Geography 26 (6), pp. 627,638. Schwartz, P., and Randall, D. (2003). An abrupt climate change scenario and its implications for United States national security. San Francisco, CA: Global Business Network. [online]. Retrieved on 8 April 2007 from http://www.gbn.com/ArticleDisplayServlet.srv?aid=26231 Focus Questions 1Who is most responsible for climate change? 2Who is most vulnerable to climate change? 3Does everyone have equal power in the UNFCCC process? 4Will climate change force people to migrate? Who? 5What is the relationship between adaptation to climate change and violent conflict? [source] Teaching and Learning Guide for: Memoryscape: How Audio Walks Can Deepen Our Sense of Place by Integrating Art, Oral History and Cultural GeographyGEOGRAPHY COMPASS (ELECTRONIC), Issue 5 2008Toby Butler Author's Introduction This article is concerned with the history and practice of creating sound walks or ,memoryscapes': outdoor trails that use recorded sound and spoken memory played on a personal stereo or mobile media to experience places in new ways. It is now possible to cheaply and easily create this and other kinds of located media experience. The development of multi-sensory-located media (,locedia') presents some exciting opportunities for those concerned with place, local history, cultural geography and oral history. This article uses work from several different disciplines (music, sound art, oral history and cultural geography) as a starting point to exploring some early and recent examples of locedia practice. It also suggests how it might give us a more sophisticated, real, embodied and nuanced experience of places that the written word just can not deliver. Yet, there are considerable challenges in producing and experiencing such work. Academics used to writing must learn to work in sound and view or image; they must navigate difficult issues of privacy, consider the power relations of the outsider's ,gaze' and make decisions about the representation of places in work that local people may try and have strong feelings about. Creating such work is an active, multi-sensory and profoundly challenging experience that can offer students the chance to master multi-media skills as well as apply theoretical understandings of the histories and geographies of place. Author Recommends 1.,Perks, R., and Thomson, A. (2006). The oral history reader, 2nd ed. London: Routledge. This is a wonderful collection of significant writing concerned with oral history. Part IV, Making Histories features much of interest, including a thought-provoking paper on the challenges of authoring in sound rather than print by Charles Hardy III, and a moving interview with Graeme Miller, the artist who created the Linked walk mentioned in the memoryscape article. These only feature in the second edition. 2.,Cresswell, T. (2004). Place: a short introduction. Oxford, UK: Blackwell. A refreshingly clear and well-written guide to the different theoretical takes on what makes places , a good starting point for further reading. 3.,Carlyle, A. (ed.). (2008). Autumn leaves: sound and the environment in artistic practice. Paris, France: Double Entendre. This is a collection of short essays and examples of located sonic media art; it includes interviews with practitioners and includes Hildegard Westekamp's Soundwalking, a practical guide to leading students on a mute walk. Lots of thought provoking, applied reading material for students here. 4.,Blunt, A., et al. (eds) (2003). Cultural geography in practice. London: Arnold. A great book for undergraduate and postgraduate students , concepts explained and lots of examples of actually doing cultural geography. The chapter on mapping worlds by David Pinder is particularly useful in this context. 5.,Pinder, D. (2001). Ghostly footsteps: voices, memories and walks in the city. Ecumene 8 (1), pp. 1,19. This article is a thoughtful analysis of a Janet Cardiff sound walk in Whitechapel, East London. Online Materials http://www.memoryscape.org.uk This is my project website, which features two online trails, Dockers which explores Greenwich and the memories of the London Docks that are archived in the Museum of London, and Drifting which is a rather strange experiment-combining physical geography and oral history along the Thames at Hampton Court, but still makes for an interesting trail. Audio, maps and trails can be downloaded for free, so students with phones or iPods can try the trails if you are within reach of Surrey or London. The site features an online version, with sound-accompanying photographs of the location. http://www.portsofcall.org.uk This website has three more trails here, this time of the communities surrounding the Royal Docks in East London. The scenery here is very dramatic and anyone interested in the regeneration of East London and its impact on local communities will find these trails interesting. Like Dockers, the walks feature a lot of rare archive interviews. This project involved a great deal of community interaction and participation as I experimented with trying to get people involved with the trail-making process. The site uses Google maps for online delivery. http://www.soundwalk.com This New York-based firm creates exceptionally high-quality soundwalks, and they are well worth the money. They started by producing trails for different districts of New York (I recommend the Bronx Graffiti trail) and have recently made trails for other cities, like Paris and Varanassi in India. http://www.mscapers.com This website is run by Hewlett Packard, which has a long history of research and development in located media applications. They currently give free licence to use their mscape software which is a relatively easy to learn way of creating global positioning system-triggered content. The big problem is that you have to have a pricey phone or personal digital assistant to run the software, which makes group work prohibitively expensive. But equipment prices are coming down and with the new generations of mobile phones developers believe that the time when the player technology is ubiquitous might be near. And if you ask nicely HP will lend out sets of equipment for teaching or events , fantastic if you are working within reach of Bristol. See also http://www.createascape.org.uk/ which has advice and examples of how mscape software has been used for teaching children. Sample Syllabus public geography: making memoryscapes This course unit could be adapted to different disciplines, or offered as a multidisciplinary unit to students from different disciplines. It gives students a grounding in several multi-media techniques and may require support/tuition from technical staff. 1.,Introduction What is a located mediascape, now and in the future? Use examples from resources above. 2.,Cultural geographies of site-specific art and sound Theories of place; experiments in mapping and site-specific performance. 3.,Walk activity: Westergard Hildekamp , sound walk, or one of the trails mentioned above The best way , and perhaps the only way , to really appreciate located media is to try one in the location they have been designed to be experienced. I would strongly advise any teaching in this field to include outdoor, on-site experiences. Even if you are out of reach of a mediascape experience, taking students on a sound walk can happen anywhere. See Autumn Leaves reference above. 4.,Researching local history An introduction to discovering historical information about places could be held at a local archive and a talk given by the archivist. 5.,Creating located multimedia using Google maps/Google earth A practical exercise-based session going through the basics of navigating Google maps, creating points and routes, and how to link pictures and sound files. 6.,Recording sound and oral history interviews A practical introduction to the techniques of qualitative interviewing and sound recording. There are lots of useful online guides to oral history recording, for example, an online oral history primer http://www.nebraskahistory.org/lib-arch/research/audiovis/oral_history/index.htm; a more in depth guide to various aspects of oral history http://www.baylor.edu/oral%5fhistory/index.php?id=23566 or this simple oral history toolkit, with useful links to project in the North of England http://www.oralhistorynortheast.info/toolkit/chapter1.htm 7.,Sound editing skills Practical editing techniques including working with clips, editing sound and creating multi-track recordings. The freeware software Audacity is simple to use and there are a lot of online tutorials that cover the basics, for example, http://www.wikieducator.org/user:brentsimpson/collections/audacity_workshop 8.,Web page design and Google maps How to create a basic web page (placing pictures, text, hyperlinks, buttons) using design software (e.g. Dreamweaver). How to embed a Google map and add information points and routes. There is a great deal of online tutorials for web design, specific to the software you wish to use and Google maps can be used and embedded on websites free for non-profit use. http://maps.google.com/ 9,and 10. Individual or group project work (staff available for technical support) 11.,Presentations/reflection on practice Focus Questions 1What can sound tell us about the geographies of places? 2When you walk through a landscape, what traces of the past can be sensed? Now think about which elements of the past have been obliterated? Whose past has been silenced? Why? How could it be put back? 3Think of a personal or family story that is significant to you. In your imagination, locate the memory at a specific place. Tell a fellow student that story, and describe that place. Does it matter where it happened? How has thinking about that place made you feel? 4What happens when you present a memory of the past or a located vision of the future in a present landscape? How is this different to, say, writing about it in a book? 5Consider the area of this campus, or the streets immediately surrounding this building. Imagine this place in one of the following periods (each group picks one): ,,10,000 years ago ,,500 years ago ,,100 years ago ,,40 years ago ,,last Thursday ,,50 years time What sounds, voices, stories or images could help convey your interpretation of this place at that time? What would the visitor hear or see today at different points on a trail? Sketch out an outline map of a located media trail, and annotate with what you hear/see/sense at different places. Project Idea small group project: creating a located mediascape Each small group must create a located media experience, reflecting an aspect of the history/geography/culture of an area of their choosing, using the knowledge that they have acquired over the course of the semester. The experience may be as creative and imaginative as you wish, and may explore the past, present or future , or elements of each. Each group must: ,,identify an area of interest ,,research an aspect of the area of the groups choosing; this may involve visiting local archives, libraries, discussing the idea with local people, physically exploring the area ,,take photographs, video or decide on imagery (if necessary) ,,record sound, conduct interviews or script and record narration ,,design a route or matrix of media points The final project must be presented on a website, may embed Google maps, and a presentation created to allow the class to experience the mediascape (either in the classroom or on location, if convenient). The website should include a brief theoretical and methodological explanation of the basis of their interpretation. If the group cannot be supported with tuition and support in basic website design or using Google mapping with sound and imagery, a paper map with locations and a CD containing sound files/images might be submitted instead. For examples of web projects created by masters degree students of cultural geography at Royal Holloway (not all sound based) see http://www.gg.rhul.ac.uk/MA/web-projects.html [source] Reply to comment on ,Siegel D. 2008.HYDROLOGICAL PROCESSES, Issue 11 2009Reductionist hydrogeology: ten fundamental principles. No abstract is available for this article. [source] The immune system: a weapon of mass destruction invented by evolution to even the odds during the war of the DNAsIMMUNOLOGICAL REVIEWS, Issue 1 2002Melvin Cohn Summary: Living systems operate under interactive selective pressures. Populations have the ability to anticipate the future by generating a repertoire of elements that cope with new selective pressures. If the repertoire of such elements were transcendental, natural selection could not operate because any one of them would be too rare. This is the problem that vertebrates faced in order to deal with a vast number of pathogens. The solution was to invent an immune system that underwent somatic evolution. This required a random repertoire that was generated somatically and divided the antigenic universe into combinatorials of determinants. As a result, it became virtually impossible for pathogens to escape recognition but the functioning of such a repertoire required two new regulatory mechanisms: 1) a somatic discriminator between Not-To-Be-Ridded (,Self') and To-Be-Ridded (,Non-self') antigens, and 2) a way to optimize the magnitude and choice of the class of the effector response. The principles governing this dual regulation are analyzed in the light of natural selection. Abstract I.,Introduction A. ,...doth protest too much' Living things obey the laws of natural selection What started the wars between the DNAs? The passage from germline to somatic evolution? E. Two classes of pathogen must be faced F. Two pathways are required for a successful immune response, II. The NTBR,TBR discrimination A. The three laws of the NTBR-TBR discrimination B. The mechanism of the NTBR-TBR discrimination C. Facing the "chicken and egg" problem III. The regulation of effector class IV. The somatically selected immune repertoire A. The Protecton is the unit of function B. The humoral immune system C. The cell-mediated immune system D. The meaning of specificity V. Why understand when you can cure without it? VI. Coda: Extracting the postulates used to explain immune behavior O.K. José! What would it take to change your mind? Mechkonik [source] Report on the vitamin D status of adult and pediatric patients with inflammatory bowel disease and its significance for bone health and diseaseINFLAMMATORY BOWEL DISEASES, Issue 12 2006Helen M. Pappa MD Abstract Vitamin D is a hormone responsible for calcium homeostasis and essential for bone mineralization throughout the lifespan. Recent studies revealed a high prevalence of hypovitaminosis D among healthy adults and children, especially in the northern hemisphere, and a link between this condition and suboptimal bone health. Moreover, maintenance of what are today considered optimal vitamin D stores has not been achieved throughout the year with currently recommended daily intake for vitamin D. The prevalence of hypovitaminosis D is even higher among adults with inflammatory bowel disease (IBD), a situation that may be caused by malabsorption and gastrointestinal losses through an inflamed intestine, among other factors. In children with IBD, existing reports of vitamin D status are scarce. The relationship between vitamin D status and bone health, although well-established in healthy adults and children, has been controversial among adults and children with IBD, and the reasons for this have not been investigated to date. Studies in animal models of colitis and in vitro human studies support a role of vitamin D in the regulation of the immune system of the gut and the potential of vitamin D and its derivatives as therapeutic adjuncts in the treatment of IBD. This role of vitamin D has not been investigated with translational studies to date. Currently, there are no guidelines for monitoring vitamin D status, treating hypovitaminosis D, and maintaining optimal vitamin D stores in patients with IBD. These tasks may prove particularly difficult because of malabsorption and gastrointestinal losses that are associated with IBD. [source] Molecular phylogeny of Diabrotica beetles (Coleoptera: Chrysomelidae) inferred from analysis of combined mitochondrial and nuclear DNA sequencesINSECT MOLECULAR BIOLOGY, Issue 4 2001T. L. Clark Abstract The phylogenetic relationships of thirteen Diabrotica (representing virgifera and fucata species groups) and two outgroup Acalymma beetle species (Coleoptera: Chrysomelidae) were inferred from the phylogenetic analysis of a combined data set of 1323 bp of mitochondrial DNA (mtDNA) cytochrome oxidase subunit 1 (COI) and the entire second internal transcribed spacer region (ITS-2) of nuclear ribosomal DNA of 362 characters. Species investigated were D. adelpha, D. balteata, D. barberi, D. cristata, D. lemniscata, D. longicornis, D. porracea, D. speciosa, D. undecimpunctata howardi, D. u. undecimpunctata, D. virgifera virgifera, D. v. zeae, D. viridula, and outgroup A. blandulum and A. vittatum. Maximum parsimony (MP), minimum evolution (ME), and maximum likelihood (ML) analyses of combined COI and ITS-2 sequences clearly place species into their traditional morphological species groups with MP and ME analyses resulting in identical topologies. Results generally confer with a prior work based on allozyme data, but within the virgifera species group, D. barberi and D. longicornis strongly resolve as sister taxa as well as monophyletic with the neotropical species, D. viridula, D. cristata and D. lemniscata also resolve as sister taxa. Both relationships are not in congruence with the prior allozyme-based hypothesis. Within the fucata species group, D. speciosa and D. balteata resolve as sister taxa. Results also strongly supported the D. virgifera and D. undecimpunctata subspecies complexes. Our proposed phylogeny provides some insight into current hypotheses regarding distribution status and evolution of various life history traits for Diabrotica. [source] Experimental study of stick-slip behaviourINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 6 2004Florence Adjemian Abstract Simple axi-symmetric uni-axial compression tests have been realized on dry loose samples of glass beads (diameters d: d=0.2 ± 0.05 mm, 0.75 ± 0.1 mm, or 3 mm) and on Hostun sand under small lateral confinement, ,3<60 kPa, using different sample sizes. The experiments with the two smallest spheres (d=0.2 and 0.75 mm) exhibit stick-slips, which are characterized by (i) a rapid release ,q of the deviatoric stress q and by (ii) the strain ,,1 separating two events. The samples which exhibit stick-slip also present a weakening of strength q(,1) as the rate of deformation d,1/dt is increased. No stick-slip is generated during the first part of the q,,1 curve, i.e. when q grows fast with ,1. Four different parameters helped us determine the statistics of ,q and ,,: the lateral pressure ,3,, the rate of deformation d,1/dt, the sample height H, and the diameter D. The statistics do not depend on rate history. They look like exponentials in small samples and/or in (large sample+fast d,1/dt), and they look like Poissonian or Gaussian in (Large sample+small d,1/dt). This change in statistics is attributed to a varying of triggering process starting from a single random event in small samples to multiple random events. We have interpreted this change of statistics as due to some finite size effect so that the representative elementary volume shall contain at least (200)3 grains. Localization of deformation is visible at the end of compression but cannot be detected from stick-slip statistics nor from q vs , curve. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||