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Resemblance
Kinds of Resemblance Selected Abstracts5-Benzyl-3-methylimidazolidin-4-one-Derived Reactive Intermediates of Organocatalysis , A Comforting Resemblance of X-Ray, NMR, and DFT Solid-Phase, Liquid-Phase, and Gas-Phase StructuresHELVETICA CHIMICA ACTA, Issue 1 2009Abstract The X-ray crystal structures of three (E)-1-cinnamoylidene iminium PF6 salts of 5-benzyl-3-methylimidazolidin-4-ones (2,2-dimethyl-, cis -2-(tert -butyl)-, and cis -2-styryl-substituted; 2,4, resp.) are reported (Figs.,3,5). In the 2,2-dimethyl and in the cis -2-styryl derivative, 2 and 4, respectively, a CH bond of the cis -substituent in 2-position points to the center of the benzene ring of the benzyl group above the five-membered ring (Fig.,6,,a and b). NMR Measurements (Fig.,8) provide evidence that the same structure is present in solution, and that a fourth derivative of this type, 5 (Scheme), has (Z)- instead of (E)-configuration around the CN bond. In the cis -2-(tert -butyl) derivative 3, the benzyl group is located over the iminium , -system (Figs.,4 and 6,,c). Overlays with DFT-calculated crotonylidene analogs, A and B, show that the theoretical and experimental structures are almost superimposable (Fig.,9 and Table). The structures are discussed in view of their role as reactive intermediates in organocatalysis and in view of the help synthetic organic chemists may experience from theory. [source] Resemblance of osteophytes in experimental osteoarthritis to transforming growth factor ,,induced osteophytes: Limited role of bone morphogenetic protein in early osteoarthritic osteophyte formationARTHRITIS & RHEUMATISM, Issue 12 2007E. N. Blaney Davidson Objective Osteoarthritis (OA) is characterized by cartilage damage, synovial fibrosis, and osteophyte formation. Both transforming growth factor , (TGF,) and bone morphogenetic protein 2 (BMP-2) can induce the formation of osteophytes during OA, but their specific role in this process is unclear. The purpose of this study was to investigate the respective contributions of TGF, and BMP-2 to OA. Methods Mouse knee joints injected with adenovirus (Ad-TGF, or Ad-BMP-2) were compared histologically with knee joints from murine models of OA (joints injected with collagenase and joints from STR/Ort mice with spontaneous OA). To further investigate the role of BMP during osteophyte formation, adenovirus Ad-Gremlin was injected into knee joints that had previously been injected with Ad-TGF, or collagenase. Results BMP-2 induced early osteophytes, which bulged from the growth plates on the femur and grew on top of the patella, whereas TGF, induced early osteophyte formation on the bone shaft beneath the collateral ligament on the femur as well as on top of the patella. The pattern of osteophyte formation during experimental OA closely resembled that of TGF,-induced osteophyte formation, but differed from the pattern induced by BMP-2. Ad-Gremlin proved to be able to totally block BMP-2,induced osteophyte formation. However, blocking BMP activity inhibited neither TGF,-induced nor experimental OA,associated osteophyte formation. Conclusion Our findings demonstrate that the role of BMP during the onset of TGF,-induced and experimental OA,induced osteophyte formation is limited. The latter finding does not rule out a role of BMP during osteophyte maturation. [source] Designing mouse behavioral tasks relevant to autistic-like behaviors,DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2004Jacqueline N. Crawley Abstract The importance of genetic factors in autism has prompted the development of mutant mouse models to advance our understanding of biological mechanisms underlying autistic behaviors. Mouse models of human neuropsychiatric diseases are designed to optimize (1) face validity, i.e., resemblance to the human symptoms; (2) construct validity, i.e., similarity to the underlying causes of the disease; and (3) predictive validity, i.e., expected responses to treatments that are effective in the human disease. There is a growing need for mouse behavioral tasks with all three types of validity for modeling the symptoms of autism. We are in the process of designing a set of tasks with face validity for the defining features of autism: deficits in appropriate reciprocal social interactions, deficits in verbal social communication, and high levels of ritualistic repetitive behaviors. Social approach is tested in an automated three-chambered apparatus that offers the subject a choice between a familiar environment, a novel environment, and a novel environment containing a stranger mouse. Preference for social novelty is tested in the same apparatus, with a choice between the start chamber, the chamber containing a familiar mouse, and the chamber containing a stranger mouse. Social communication is evaluated by measuring the ultrasonic distress vocalizations emitted by infant mouse pups and the parental response of retrieving the pup to the nest. Resistance to change in ritualistic repetitive behaviors is modeled by forcing a change in habit, including reversal of the spatial location of a reinforcer in a T-maze task and in the Morris water maze. Mouse behavioral tasks that may model additional features of autism are discussed, including tasks relevant to anxiety, seizures, sleep disturbances, and sensory hypersensitivity. Applications of these tests include (1) behavioral phenotyping of transgenic and knockout mice with mutations in genes relevant to autism, (2) characterization of mutant mice derived from random chemical mutagenesis, (3) DNA microarray analyses of genes in inbred strains of mice that differ in social interaction, social communication and resistance to change in habit, and (4) evaluation of proposed therapeutics for the treatment of autism. Published 2004 Wiley-Liss, Inc. MRDD Research Reviews 2004;10:248,258. [source] Is the Partial Identity Account of Property Resemblance Logically Incoherent?DIALECTICA, Issue 4 2007Winner of the 2006 dialectica essay prize According to the partial identity account of resemblance, exact resemblance is complete identity and inexact resemblance is partial identity. In this paper, I examine Arda Denkel's (1998) argument that this account of resemblance is logically incoherent as it results in a vicious regress. I claim that although Denkel's argument does not succeed, a modified version of it leads to the conclusion that the partial identity account is plausible only if the constituents of every determinate property are ultimately quantitative in nature. [source] Diagrammatic Representation in GeometryDIALECTICA, Issue 4 2006Dennis Potter In this paper I offer a theory about the nature of diagrammatic representation in geometry. On my view, diagrammatic representaiton differs from pictorial representation in that neither the resemblance between the diagram and its object nor the experience of such a resemblance plays an essential role. Instead, the diagrammatic representation is arises from the role the components of the diagram play in a diagramatic practice that allows us to draws inferences based on them about the ojbects they represent. [source] DIAGNOSIS AND CLINICAL COURSE OF ULCERATIVE GASTRODUODENAL LESION ASSOCIATED WITH ULCERATIVE COLITIS: POSSIBLE RELATIONSHIP WITH POUCHITISDIGESTIVE ENDOSCOPY, Issue 4 2010Takashi Hisabe Background and Aim:, Ulcerative colitis (UC) is not only characterized by pathological lesions localized to colonic mucosa, but also to various complications involving other organs, including postoperative pouchitis. Among these complications, diffuse gastroduodenitis with lesions resembling colonic lesions has been reported, albeit rarely. The aim of the present study was to attempt to characterize the lesions of the upper gastrointestinal tract occurring as a complication of UC, and to assess the frequency and clinical course of these lesions. Methods:, A total of 322 UC patients who had undergone upper gastrointestinal endoscopy were retrospectively analyzed. We assessed the frequency of endoscopic findings, including diffuse gastroduodenal lesions resembling colonic lesions. Ulcerative gastroduodenal lesion (UGDL) associated with UC was diagnosed if lesions satisfied the following criteria: (i) improvement of the lesions with treatment of UC; and/or (ii) resemblance to UC in pathological findings. Results:, UGDL satisfying the aforementioned criteria was found in 15 (4.7%) of 322 patients. All the 15 patients had UGDL accompanied by pancolitis or after proctocolectomy. Frequency in 146 patients with pancolitis was 6.2% (nine patients) and that in 81 patients who had undergone proctocolectomy was 7.4% (six patients). Four patients with diffuse ulcerative upper-gastrointestinal mucosal inflammation (DUMI) had pouchitis. In all patients except one, the lesions resolved easily with medical treatment. Conclusions:, In more than half of the post-proctocolectomy patients, UGDL was related to the occurrence of pouchitis. The existence of characteristic UGDL must be taken into account in the diagnosis and treatment of UC, and UGDL is possibly related to the occurrence of pouchitis. [source] New arthrodires (Family Williamsaspididae) from Wee Jasper, New South Wales (Early Devonian), with comments on placoderm morphology and palaeoecologyACTA ZOOLOGICA, Issue 2009Gavin C. Young Abstract Two new arthrodire species represented by articulated trunk armours from the Early Devonian (Emsian) limestones of the Burrinjuck area are placed in a new genus Elvaspis (E. tuberculata, E. whitei), assigned to the Family Williamsaspididae. On new evidence of the dermal neck-joint and shape of the median dorsal plate this family is reassigned from the Phlyctaeniina to the Brachythoraci. The strongly ornamented post-branchial lamina of the trunk armour relates to a recent hypothesis that special post-branchial denticles in placoderms are homologous to pharyngeal denticles of crown-gnathostomes rather than modified external tubercles. Variable development of the post-branchial lamina and its ornament in different placoderm subgroups, with specific resemblance to the external ornament characteristic of that subgroup, indicates that modification of normal external dermal ornament is the most parsimonious interpretation. A comparison of fish diversity in modern and ancient tropical reef environments is consistent with an equilibrium model for species diversification through time. [source] Invasive exotic aoudad (Ammotragus lervia) as a major threat to native Iberian ibex (Capra pyrenaica): a habitat suitability model approachDIVERSITY AND DISTRIBUTIONS, Issue 5 2007Pelayo Acevedo ABSTRACT The introduction of alien species to new environments is one of the main threats to the conservation of biodiversity. One particularly problematic example is that of wild ungulates which are increasingly being established in regions outside their natural distribution range due to human hunting interests. Unfortunately, we know little of the effects these large herbivores may have on the host ecosystems. This study deals with a first comparative analysis of the habitat requirements of two ungulate species that may be facing competition for resources in the south of Europe: the native Iberian ibex (Capra pyrenaica) and the exotic aoudad (Ammotragus lervia). The aoudad is a North African caprid introduced in 1970 as a game species in south-eastern Spain. It has adapted well, and populations have been freely expanding since then. Ecological Niche Factor Analysis is used to describe the realized niche of both species where their distribution ranges merge. Both species occupy marginal areas of rugged terrain in the region. Marginality is higher for the Iberian ibex, which also presents a higher tolerance of secondary environmental gradients than the aoudad. Highly suitable areas for each species are secondarily suitable for the other. Reclassified and cross-tabulated habitat suitability maps showing the areas of potential spatial coexistence and differences in ecological traits between both species are provided. The results obtained do not allow inferring resource competition between these species. However, current aoudad expansion could result in it invading the favoured habitats of the ibex. Inadequate hunting policy and monitoring, and increasing climatic resemblance of the study region to the native aoudad areas, due to a strong desertification process, are facilitating a high rate of expansion. We strongly recommend to eradicate or, at least, monitor these exotic populations, and promote active conservation practices, if one wants to preserve the unique natural resources present in this European region. [source] Characteristics and dynamics of multiple intertidal bars, north Lincolnshire, EnglandEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2006Selma van Houwelingen Abstract Multiple intertidal bars and troughs, often referred to as ,ridges and runnels', are significant features on many macrotidal sandy beaches. Along the coastline of England and Wales, they are particularly prevalent in the vicinity of estuaries, where the nearshore gradient is gentle and a large surplus of sediment is generally present. This paper examines the dynamics of such bar systems along the north Lincolnshire coast. A digital elevation model of the intertidal morphology obtained using LIDAR demonstrates that three to five intertidal bars are consistently present with a spacing of approximately 100 m. The largest and most pronounced bars (height = 0·5,0·8 m) are found around mean sea level, whereas the least developed bars (height = 0·2,0·5 m) occur in the lower intertidal zone. Annual aerial photographs of the intertidal bar morphology were inspected to try to track individual bars from year to year to derive bar migration rates; however, there is little resemblance between concurrent photographs, and ,resetting' of the intertidal profile occurs on an annual basis. Three-dimensional beach surveys were conducted monthly at three locations along the north Lincolnshire coast over a one-year period. The intertidal bar morphology responds strongly to the seasonal variation in the forcing conditions, and bars are least numerous and flattest during the more energetic winter months. Morphological changes over the monthly time scale are strongly affected by longshore sediment transport processes and the intertidal bar morphology can migrate along the beach at rates of up to 30 m per month. The behaviour of intertidal bars is complex and varies over a range of spatial and temporal scales in response to a combination of forcing factors (e.g. incident wave energy, different types of wave processes, longshore and cross-shore sediment transport), relaxation time and morphodynamic feedback. Copyright © 2005 John Wiley & Sons, Ltd. [source] Assessing a numerical cellular braided-stream model with a physical modelEARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2005Andrea B. Doeschl-Wilson Abstract A. B. Murray and C. Paola (1994, Nature, vol. 371, pp. 54,57; 1997, Earth Surface Processes and Landforms, vol. 22, pp. 1001,1025) proposed a cellular model for braided river dynamics as an exploratory device for investigating the conditions necessary for the occurrence of braiding. The model reproduces a number of the general morphological and dynamic features of braided rivers in a simplified form. Here we test the representation of braided channel morphodynamics in the Murray,Paola model against the known characteristics (mainly from a sequence of high resolution digital elevation models) of a physical model of a braided stream. The overall aim is to further the goals of the exploratory modelling approach by first investigating the capabilities and limitations of the existing model and then by proposing modifications and alternative approaches to modelling of the essential features of braiding. The model confirms the general inferences of Murray and Paola (1997) about model performance. However, the modelled evolution shows little resemblance to the real evolution of the small-scale laboratory river, although this depends to some extent on the coarseness of the grid used in the model relative to the scale of the topography. The model does not reproduce the bar-scale topography and dynamics even when the grid scale and amplitude of topography are adapted to be equivalent to the original Murray,Paola results. Strong dependence of the modelled processes on local bed slopes and the tendency for the model to adopt its own intrinsic scale, rather than adapt to the scale of the pre-existing topography, appear to be the main causes of the differences between numerical model results and the physical model morphology and dynamics. The model performance can be improved by modification of the model equations to more closely represent the water surface but as an exploratory approach hierarchical modelling promises greater success in overcoming the identified shortcomings. Copyright © 2005 John Wiley & Sons, Ltd. [source] Metacommunity patterns of highly diverse stream midges: gradients, chequerboards, and nestedness, or is there only randomness?ECOLOGICAL ENTOMOLOGY, Issue 5 2005Jani Heino Abstract., 1.,Several non-random patterns in the distribution of species have been observed, including Clementsian gradients, Gleasonian gradients, nestedness, chequerboards, and evenly spaced gradients. Few studies have examined these patterns simultaneously, although they have often been studied in isolation and contrasted with random distribution of species across sites. 2.,This study examined whether assemblages of chironomid midges exhibit any of the idealised distribution patterns as opposed to random distribution of species across sites within the metacommunity context in a boreal drainage system. Analyses were based on stream surveys conducted during three consecutive years. Analytical approaches included ordinations, cluster analysis, null models, and associated randomisation methods. 3.,Midge assemblages did not conform to Clementsian gradients, which was evidenced by the absence of clearly definable assemblage types with numerous species exclusive to each assemblage type. Rather, there were signs of continuous Gleasonian variability of assemblage composition, as well as significant nested subset patterns of species distribution. 4.,Midge assemblages showed only weak relationships with any of the measured environmental variables, and even these weak environmental relationships varied among years. 5.,Midge assemblages did not appear to be structured by competition. This finding was somewhat problematic, however, because the two indices measuring co-occurrence provided rather different signs of distribution patterns. This was probably a consequence of how they actually measure co-occurrence. 6.,Although midge assemblages did not show a perfect match with any of the idealised distribution patterns, they nevertheless showed a resemblance to the empirical patterns found previously for several plant and animal groups. [source] An Extended Analytical Approach to Credit Risk ManagementECONOMIC NOTES, Issue 2 2002Alexandre Kurth Among the ,reduced form models' for measuring the credit risk of a bank's portfolio is CreditRisk+, which provides a closed,form solution for calculating the portfolio loss distribution based on an actuarial approach. The limitations of this model are well known, but they are often misinterpreted as being deeply embedded within the model. Dismantling the mathematical components of the model allows one to modify and extend it in several ways while remaining within an analytical approach. One of the most unattractive features is the orthogonality of the background factors or sectors as it hinders any resemblance to real,world macroeconomic indexes or industrial sectors and geographical areas. Among other extensions, which we mention briefly, we present in more detail how the original model can be amended to consider correlations among default risk sectors and among severity risk segments. These extensions are applied to real,life data, based on mortality rate data produced by the Italian Central Bank. (J.E.L.: C00, C51). [source] Skin and heart: une liaison dangereuseEXPERIMENTAL DERMATOLOGY, Issue 8 2009Maria C. Bolling Abstract:, Both skin and heart are subject to shear mechanical stress and need to be stress-resistant in a flexible way. The intercellular connecting structures in skin and heart, the desmosomes, that have to resist these forces show remarkable resemblance in epidermis and myocardium. Mutations in desmosomal proteins lead to inherited desmosomal cardiocutaneous syndromes (DCCS): une liaison dangereuse. This article will critically review the cutaneous and cardiac features as well as the molecular background of DCCS, such as Naxos disease and Carvajal syndrome caused by deficiencies of plakoglobin and desmoplakin respectively. In addition, potential other desmosomal gene candidates for an involvement in cardiocutaneous syndromes are considered. The skin features in these syndromes may be the hallmark for the presence of progressive and ultimately lethal cardiac disease. Knowledge of these skin features and early recognition of such a syndrome may provide opportunities to halt or slow down cardiac disease progression, treat arrhythmias and even prevent sudden death. [source] Psychotherapy as a Rite of PassageFAMILY PROCESS, Issue 4 2007C. CHRISTIAN BEELS M.D. Some psychotherapies may work because they resemble rites of passage. To explore this idea, this article describes an "individual" case of depression in which drug, cognitive, and narrative approaches fell short of effectiveness, and change occurred in a series of experiences that resemble a rite of passage. This resemblance is illuminated by examining two apparently quite different healing processes,Alcoholics Anonymous and multifamily group therapy in schizophrenia,to explore the elements they have in common with the case described: the acceptance of what Victor Turner called a liminal experience, and the importance of witnesses to the ritual support for that acceptance. The discussion contributes to a loosening of the distinctions between the processes of individual, family, group, and other social therapies and leads to questions about the expert knowledge the therapist provides. [source] Saccharomyces cerevisiae Ybr004c and its human homologue are required for addition of the second mannose during glycosylphosphatidylinositol precursor assemblyFEBS JOURNAL, Issue 5 2005Anne-Lise Fabre Addition of the second mannose is the only obvious step in glycosylphosphatidylinositol (GPI) precursor assembly for which a responsible gene has not been discovered. A bioinformatics-based strategy identified the essential Saccharomyces cerevisiae Ybr004c protein as a candidate for the second GPI ,-mannosyltransferase (GPI-MT-II). S. cerevisiae cells depleted of Ybr004cp have weakened cell walls and abnormal morphology, are unable to incorporate [3H]inositol into proteins, and accumulate a GPI intermediate having a single mannose that is likely modified with ethanolamine phosphate. These data indicate that Ybr004cp-depleted yeast cells are defective in second mannose addition to GPIs, and suggest that Ybr004cp is GPI-MT-II or an essential subunit of that enzyme. Ybr004cp homologues are encoded in all sequenced eukaryotic genomes, and are predicted to have 8 transmembrane domains, but show no obvious resemblance to members of established glycosyltransferase families. The human Ybr004cp homologue can substitute for its S. cerevisiae counterpart in vivo. [source] Soluble LDL-R are formed by cell surface cleavage in response to phorbol estersFEBS JOURNAL, Issue 3 2004Michael J. Begg A 140-kDa soluble form of the low density lipoprotein (LDL) receptor has been isolated from the culture medium of HepG2 cells and a number of other cell types. It is produced from the 160-kDa mature LDL receptor by a proteolytic cleavage, which is stimulated in the presence of 4,-phorbol 12-myristate 13-acetate (PMA), leading to the release of a soluble fragment that constitutes the bulk of the extracellular domain of the LDL receptor. By labeling HepG2 cells with [35S]methionine and chasing in the presence of PMA, we demonstrated that up to 20% of LDL-receptors were released into the medium in a 2-h period. Simultaneously, the level of labeled cellular receptors was reduced by 30% in those cells treated with PMA compared to untreated cells, as was the total number of cell surface LDL-receptors assayed by the binding of 125I-labeled antibody to whole cells. To determine if endocytosis was required for cleavage, internalization-defective LDL-receptors were created by mutagenesis or deletion of the NPXY internalization signal, transfected into Chinese hamster ovary cells, and assayed for cleavage in the presence and absence of PMA. Cleavage was significantly greater in the case of the mutant receptors than for wild-type receptors, both in the absence and presence of PMA. Similar results were seen in human skin fibroblasts homozygous for each of the internalization-defective LDL receptor phenotypes. LDL receptor cleavage was inhibited by the hydoxamate-based inhibitor TAPI, indicating the resemblance of the LDL receptor cleavage mechanism to that of other surface released membrane proteins. [source] Domain V of m-calpain shows the potential to form an oblique-orientated ,-helix, which may modulate the enzyme's activity via interactions with anionic lipidFEBS JOURNAL, Issue 22 2002Klaus Brandenburg The activity of m-calpain, a heterodimeric, Ca2+ -dependent cysteine protease appears to be modulated by membrane interactions involving oblique-orientated ,-helix formation by a segment, GTAMRILGGVI, in the protein's smaller subunit. Here, graphical and hydrophobic moment-based analyses predicted that this segment may form an ,-helix with strong structural resemblance to the influenza virus peptide, HA2, a known oblique-orientated ,-helix former. Fourier transform infrared spectroscopy showed that a peptide homologue of the GTAMRILGGVI segment, VP1, adopted low levels of ,-helical structure (, 20%) in the presence of zwitterionic lipid and induced a minor decrease (3 °C) in the gel to liquid-crystalline phase transition temperature, TC, of the hydrocarbon chains of zwitterionic membranes, suggesting interaction with the lipid headgroup region. In contrast, VP1 adopted high levels of ,-helical structure (65%) in the presence of anionic lipid, induced a large increase (10 °C) in the TC of anionic membranes, and showed high levels of anionic lipid monolayer penetration (,SP = 5.5 mN·m,1), suggesting deep levels of membrane penetration. VP1 showed strong haemolytic ability (LD50 = 1.45 mm), but in the presence of ionic agents, this ability, and that of VP1 to penetrate anionic lipid monolayers, was greatly reduced. In combination, our results suggest that m-calpain domain V may penetrate membranes via the adoption of an oblique-orientated ,-helix and electrostatic interactions. We speculate that these interactions may involve snorkelling by an arginine residue located in the polar face of this ,-helix. [source] On the reproducibility of microcosm experiments , different community composition in parallel phototrophic biofilm microcosmsFEMS MICROBIOLOGY ECOLOGY, Issue 2 2006Guus Roeselers Abstract Phototrophic biofilms were cultivated simultaneously using the same inoculum in three identical flow-lane microcosms located in different laboratories. The growth rates of the biofilms were similar in the different microcosms, but denaturing gradient gel electrophoresis (DGGE) analysis of both 16S and 18S rRNA gene fragments showed that the communities developed differently in terms of species richness and community composition. One microcosm was dominated by Microcoleus and Phormidium species, the second microcosm was dominated by Synechocystis and Phormidium species, and the third microcosm was dominated by Microcoleus- and Planktothrix -affiliated species. No clear effect of light intensity on the cyanobacterial community composition was observed. In addition, DGGE profiles obtained from the cultivated biofilms showed a low resemblance with the profiles derived from the inoculum. These findings demonstrate that validation of reproducibility is essential for the use of microcosm systems in microbial ecology studies. [source] Mimicry in plant-parasitic fungiFEMS MICROBIOLOGY LETTERS, Issue 2 2006Henry K. Ngugi Abstract Mimicry is the close resemblance of one living organism (the mimic) to another (the model), leading to misidentification by a third organism (the operator). Similar to other organism groups, certain species of plant-parasitic fungi are known to engage in mimetic relationships, thereby increasing their fitness. In some cases, fungal infection can lead to the formation of flower mimics (pseudoflowers) that attract insect pollinators via visual and/or olfactory cues; these insects then either transmit fungal gametes to accomplish outcrossing (e.g. in some heterothallic rust fungi belonging to the genera Puccinia and Uromyces) or vector infectious spores to healthy plants, thereby spreading disease (e.g. in the anther smut fungus Microbotryum violaceum and the mummy berry pathogen Monilinia vaccinii-corymbosi). In what is termed aggressive mimicry, some specialized plant-parasitic fungi are able to mimic host structures or host molecules to gain access to resources. An example is M. vaccinii-corymbosi, whose conidia and germ tubes, respectively, mimic host pollen grains and pollen tubes anatomically and physiologically, allowing the pathogen to gain entry into the host's ovary via stigma and style. We review these and other examples of mimicry by plant-parasitic fungi and some of the mechanisms, signals, and evolutionary implications. [source] Nanocomposite Synthesis: Embryonic States of Fluorapatite,Gelatine Nanocomposites and Their Intrinsic Electric-Field-Driven Morphogenesis: The Missing Link on the Way from Atomistic Simulations to Pattern Formation on the Mesoscale (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 22 2009Mater. Fractal aggregates of fluorapatite,gelatine nanocomposites (SEM image taken by Yigit Öztan, MPI CPfS),which bears a strong resemblance to the biosystem hydroxyapatite,collagen, a key material in human bones and teeth,are formed from bundles of calcified protein molecules representing the first (embryonic) states of shape development and leading to extended processes of self-organisation. This process has been studied in detail by P. Simon et al., and is reported on page 3596. [source] CLIMATIC VARIABILITY ALONG A NORTH,SOUTH TRANSECT OF FINLAND OVER THE LAST 500 YEARS: SIGNATURE OF SOLAR INFLUENCE OR INTERNAL CLIMATE OSCILLATIONS?GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 2 2008MAXIM G. OGURTSOV ABSTRACT. Statistical analysis of a multi-centennial dendrochronological proxy dataset of regional climate, constructed across the latitudinal gradient of 1000 km, was performed. It was shown that centennial (c. 100 year), tri-decadal (27-32 year), bi-decadal (17-23 year) and decadal (9-13 year) periodicities governed the climate variability in Finland over the last five centuries. Despite the fact that many of the climatic periodicities bore great resemblance to periodicities of solar cycles, little evidence of actual solar influence on Finnish climate was found when the climate proxy records were subjected to linear correlation analysis with sunspot numbers. Highly non-linear response of Northern Fennoscandian climate to solar forcing might be a cause of this result, as well as influence of terrestrial climatic processes (e.g. effect of other forcing factors and internal dynamics of regional climate). Our results show that the presence of internal climate variability at time-scales of solar activity might distort the solar signature in climatic data and complicate its detection. [source] Pathology of peripheral intrahepatic cholangiocarcinoma with reference to tumorigenesisHEPATOLOGY RESEARCH, Issue 4 2008Yasuni Nakanuma Cholangiocarcinomas (CCs) are neoplasms with cholangiocyte differentiation, and may arise from cholangiocytes of the biliary tree and possibly cholangiocyte progenitor cells. Intrahepatic CCs can be divided into the perihilar and peripheral types. Peripheral CCs present grossly as a mass forming tumor, and histologically as an adenocarcinoma of varying shapes and phenotypes. Some peripheral CCs (ductular type) are characterized by: (i) a histological resemblance to reactive bile ductules; (ii) the expression of neural cell adhesion molecule (NCAM) and vimentin. This type shows: (i) grossly, a blurred border; and (ii) histologically, carcinoma cells replacing the adjoining hepatocytes at the border of the tumor. It is frequently associated with neutrophilic infiltration and also with granulocyte and granulocyte macrophage colony-stimulating factors. We propose to call this type "ductular CC." The other peripheral CC (duct type) includes ordinary adenocarcinoma with well to moderately differentiated tubular and micropapillary patterns and is negative for NCAM but positive for mucin. This type can be called "duct CC," and shows a rather compressive growth. Interestingly, CC components of combined hepatocellular CC share the features of ductular CC, suggesting that hepatic progenitor cells may be involved in the tumorigenesis of ductular CC. The biological behavior of ductular CC and duct CC remains obscure, and follow-up and molecular studies on these tumors are required in order for these two CCs to be recognized as disease entities, and so as to evaluate their carcinogenesis. [source] A subgroup of intrahepatic cholangiocarcinoma with an infiltrating replacement growth pattern and a resemblance to reactive proliferating bile ductules: ,bile ductular carcinoma'HISTOPATHOLOGY, Issue 3 2007K Kozaka Aims:, The histogenesis and biological behaviour of peripheral intrahepatic cholangiocarcinoma (peripheral CC) remain unclarified. The aim of this study was to examine the growth pattern of peripheral CC (24 cases) in comparison with hepatocellular carcinoma (HCC, 27 cases) and metastatic colorectal adenocarcinoma (MCA, 24 cases). Methods and results:, Tumour/surrounding liver borders were classified as: (i) fibrous encapsulation, (ii) compressive growth, and (iii) infiltrating replacement. Nineteen of 24 peripheral CCs showed (iii), whereas 23 of 27 HCCs showed (i) and 17 of 24 MCAs showed (ii). In (iii), carcinoma cells infiltrated the surrounding liver without compression, and hepatic supporting vascular structures such as portal tracts were secondarily incorporated into the tumour. In (i) and (ii), the surrounding liver was compressed and no or few portal tracts were incorporated within the tumour. Fifteen of 24 peripheral CCs were composed of carcinoma cells resembling reactive bile ductules and these cells were positive for neural cell adhesion molecule (NCAM), a marker of proliferating bile ductules. The remaining nine peripheral CCs were composed of ordinary adenocarcinoma and negative for NCAM. Conclusions:, A subgroup of peripheral CCs with an infiltrating replacement growth pattern resembles reactive bile ductules and expresses NCAM. ,Bile ductular carcinoma' may be a better term for this subgroup. [source] Environmental influences on reading-related outcomes: an adoption studyINFANT AND CHILD DEVELOPMENT, Issue 2 2007Stephen A. Petrill Abstract Evidence from intervention studies, quantitative genetic and molecular genetic studies suggests that genetic, and to a lesser extent, shared environmental influences are important to the development of reading and related cognitive skills. The Northeast-Northwest Collaborative Adoption Projects (N2CAP) is a sample of 241 adoptive families, containing 354 children and their adoptive parents. Negative parent outcome × child age interactions significantly predicted child outcomes, suggesting that shared environmental influences related to parent,offspring resemblance, although modest, are most salient in younger children. Additional analyses suggested that identified measures of the family environment largely accounted for these parent,offspring correlations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Acoustic upwinding for sub- and super-sonic turbulent channel flow at low Reynolds numberINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3 2007H. C. de LangeArticle first published online: 13 FEB 200 Abstract A recently developed asymmetric implicit fifth-order scheme with acoustic upwinding for the spatial discretization for the characteristic waves is applied to the fully compressible, viscous and non-stationary Navier,Stokes equations for sub- and super-sonic, mildly turbulent, channel flow (Re,=360). For a Mach number of 0.1, results are presented for uniform (323, 643 and 1283) and non-uniform (expanding wall-normal, 323 and 643) grids and compared to the (incompressible) reference solution found in (J. Fluid. Mech. 1987; 177:133,166). The results for uniform grids on 1283 and 643 nodes show high resemblance with the reference solution. Expanding grids are applied on 643 - and 323 -node grids. The capability of the proposed technique to solve compressible flow is first demonstrated by increasing the Mach number to 0.3, 0.6 and 0.9 for isentropic flow on the uniform 643 -grid. Next, the flow speed is increased to Ma=2. The results for the isothermal-wall supersonic flows give very good agreement with known literature results. The velocity field, the temperature and their fluctuations are well resolved. This means that in all presented (sub- and super-sonic) cases, the combination of acoustic upwinding and the asymmetric high-order scheme provides sufficient high wave-number damping and low wave-number accuracy to give numerically stable and accurate results. Copyright © 2007 John Wiley & Sons, Ltd. [source] Influence of an extract from kudzu symbiosomes containing leghemoglobin on in vitro cutaneous procollagen productionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2010J. V. Gruber J. Cosmet. Sci., 60, 475,484 (September/October 2009) Synopsis Cytoglobin is a hexacoordinateglobin protein that was recently discovered in mammals. Interestingly, of the four human globin proteins that are now known, hemoglobin, myoglobin, neuroglobin and cytoglobin, the latter appears to have the closest resemblance to strikingly similar proteins expressed in plants. In legumes, these proteins accumulate in symbiosomes (root nodules) of various legumes and are called leghemoglobin. The paper will discuss the ability of an aqueous extract from Pueraria lobata (kudzu) symbiosomes that contains leghemoglobin to stimulate procollagen production in human dermal fibroblasts. This effect may be partly due to the possibility that leghemoglobin may mimic the function of cytoglobin by shuttling oxygen to prolyl-4-hydroxylase, the enzyme responsible for oxidizing proline residues in procollagen bundles. This hypothesis is supported by DNA microarray sequencing data that demonstrate that treatment of normal human dermal fibroblasts (NHDF) with highly purified cytoglobin or leghemoglobin upregulates a number of key collagen-related genes including COL1A1 and COL1A2. [source] Undue influence of weight on self-evaluation: A population-based twin study of gender differencesINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 2 2004Ted Reichborn-Kjennerud Abstract Objective To explore the extent to which genetic and environmental factors contribute to liability to placing undue importance on weight as an indicator of self-evaluation and to determine whether differences exist across genders in the nature and magnitude of these effects. Method Self-report data were collected on 8,045 same-sex and opposite-sex twins, aged 18,31 years, from a population-based registry of Norwegian twins. Structural equation modeling was utilized to estimate the relative contribution of genetic and environmental factors to liability for undue influence of weight on self-evaluation, allowing for gender-specific effects. Results Individual variation in undue influence of weight on self-evaluation was best explained by shared and individual environmental influences. No significant gender differences were found. Shared environmental factors accounted for 31% of the variance. Discussion These results raise the possibility that there may be distinct sources of familial resemblance for different symptoms of bulimia nervosa as codified in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994). © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 35: 123,132, 2004. [source] Sails from the Roman port at Berenike, EgyptINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2001Felicity C. Wild A 1st-century AD midden deposit at Berenike, a major port on the trade route between the Roman Empire and India, has produced cotton textile fragments reinforced with a rectangular grid-pattern of cotton strips, interpreted as the remains of sails. Webbing fragments of cotton and linen, in some cases attached to stout cotton or linen cloth, may also have come from sails. The only published example of a Roman-Period sail is a linen sail of 1st-century BC-AD date from Thebes in Egypt, to which the Berenike fragments bear a close resemblance. The S-spun linen sails were presumably manufactured in Egypt. Most of the Berenike material, however, was of Z-spun cotton: an import, it is argued, of Indian origin. The construction of Mediterranean-type sails entirely from Indian materials has implications for the presence of Westerners on the Indian sub-continent. [source] Elite hotels: painting a self-portraitINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 2 2001Cailein Gillespie Abstract Commercial hospitality provision arose from a general process of modernisation, the gradual breakdown of the importance of kinship and social obligation relative to a common duty of care for those travelling away from home, and the process of urbanisation. Consequently market demand evolved for the provision of accommodation, food and beverage for those persons temporarily removed from their domestic environment. What is argued in this paper is that the original function of commercial hospitality bears scant resemblance to sophisticated potentialities for socio-economic self-expression, which manifest themselves in the form of the elite hotel sector. The manner in which contemporary consumption of elite hotels revolves around the notion of self, with multiple identities and group affiliations is explored. Conclusions focus on the elite hotel sector as a means of defining self-identities and the management implications therein for the provision of commercial hospitality in elite hotels. Copyright © 2001 John Wiley & Sons, Ltd. [source] Porcine induced pluripotent stem cells may bridge the gap between mouse and human iPSIUBMB LIFE, Issue 4 2010Miguel A. Esteban Abstract Recently, three independent laboratories reported the generation of induced pluripotent stem cells (iPSCs) from pig (Sus scrofa). This finding sums to the growing list of species (mouse, human, monkey, and rat, in this order) for which successful reprogramming using exogenous factors has been achieved, and multiple others are possibly forthcoming. But apart from demonstrating the universality of the network identified by Shinya Yamanaka, what makes the porcine model so special? On one side, pigs are an agricultural commodity and have an easy and affordable maintenance compared with nonhuman primates that normally need to be imported. On the other side, resemblance (for example, size of organs) of porcine and human physiology is striking and because pigs are a regular source of food the ethical concerns that still remain in monkeys are not applicable. Besides, the prolonged lifespan of pigs compared with other domestic species can allow exhaustive follow up of side effects after transplantation. Porcine iPSCs may thus fill the gap between the mouse model, which due to its ease is preferred for mechanistic studies, and the first clinical trials using iPSCs in humans. However, although these studies are relevant and have created significant interest they face analogous problems that we discuss herein together with potential new directions. © 2010 IUBMB IUBMB Life, 62(4): 277,282, 2010 [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||