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Multiple Processes (multiple + process)
Selected AbstractsOptimizing process allocation of parallel programs for heterogeneous clustersCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2009Shuichi Ichikawa Abstract The performance of a conventional parallel application is often degraded by load-imbalance on heterogeneous clusters. Although it is simple to invoke multiple processes on fast processing elements to alleviate load-imbalance, the optimal process allocation is not obvious. Kishimoto and Ichikawa presented performance models for high-performance Linpack (HPL), with which the sub-optimal configurations of heterogeneous clusters were actually estimated. Their results on HPL are encouraging, whereas their approach is not yet verified with other applications. This study presents some enhancements of Kishimoto's scheme, which are evaluated with four typical scientific applications: computational fluid dynamics (CFD), finite-element method (FEM), HPL (linear algebraic system), and fast Fourier transform (FFT). According to our experiments, our new models (NP-T models) are superior to Kishimoto's models, particularly when the non-negative least squares method is used for parameter extraction. The average errors of the derived models were 0.2% for the CFD benchmark, 2% for the FEM benchmark, 1% for HPL, and 28% for the FFT benchmark. This study also emphasizes the importance of predictability in clusters, listing practical examples derived from our study. Copyright © 2008 John Wiley & Sons, Ltd. [source] REREa/atrophin-2 interacts with histone deacetylase and fgf8 signaling to regulate multiple processes of zebrafish developmentDEVELOPMENTAL DYNAMICS, Issue 10 2007Nikki Plaster No abstract is available for this article. [source] The linkage between velocity patterns and sediment entrainment in a forced-pool and riffle unitEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2009D. M. Thompson Abstract A field-based project was initiated in order to characterize velocities and sediment entrainment in a forced-pool and riffle sequence. Three-dimensional velocities and turbulence intensities were measured with an acoustic Doppler velocimeter at 222 different points at three similar flows that averaged approximately 4·35 m3 s,1 within a large pool,riffle unit on North Saint Vrain Creek, Colorado. Sediment-sorting patterns were observed with the introduction of 500 tracer particles painted according to initial seeding location. Tracer particles moved sporadically during a 113 day period in response to the annual snowmelt peak flow, which reached a maximum level of 14·8 m3 s,1. Velocity data indicate high instantaneous velocities and turbulence levels in the centre of pools. Patterns of sediment deposition support the notion that stream competence is higher in the pool than the downstream riffle. Flow convergence around a large channel constriction appears to play a major role in multiple processes that include helical flow development and sediment routing, and backwater development with low velocities and turbulence levels above the constriction that may locally limit sediment supply. Jet flow, flow separation, vortex scour and turbulence generation enhance scour in the centre of pools. Ultimately, multiple processes appear to play some role in maintenance of this forced pool and the associated riffle. Copyright © 2008 John Wiley & Sons, Ltd. [source] Design and integration of eco-industrial parks for managing water resourcesENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2009Eva M. Lovelady Abstract This work is aimed at developing an optimization-based approach to the design and integration of eco-industrial parks (EIPs). Focus is given to the management of water among multiple processes in a common EIP facility. Recycle, reuse, and separation using interception devices are considered as possible strategies for managing wastewater. A source-interception-sink structural representation is used to embed potential configurations of interest. The representation accounts for the possibilities of direct recycle, material (waste) exchange, mixing and segregation of different streams, separation and treatment in interception units, and allocation to process users (sinks). Then, the EIP design problem is formulated as an optimization program whose objective is to minimize cost of the EIP while determining optimal recycle and separation strategies. A case study is solved to illustrate the applicability of the devised approach. © 2009 American Institute of Chemical Engineers Environ Prog, 2009 [source] Warming and depth interact to affect carbon dioxide concentration in aquatic mesocosmsFRESHWATER BIOLOGY, Issue 4 2008KYLA M. FLANAGAN Summary 1. Climate change may significantly influence lake carbon dynamics and consequently the exchange of CO2 with the atmosphere. Warming will accelerate multiple processes that either absorb or release CO2, making predicting the net effect of warming on CO2 exchange with the atmosphere difficult. Here we experimentally test how the CO2 flux of deep and shallow systems responds to warming. To do this, we conducted a greenhouse experiment using mesocosms of two depths, experiencing either ambient or warmed temperatures. 2. Deeper mesocosms were found to have a lower average CO2 concentration than shallower mesocosms under ambient temperature conditions. In addition, warming interacts with mesocosm depth to affect the average CO2 concentration; there was no effect of warming on the average CO2 concentration of deep mesocosms, but shallow mesocosms had significantly lower average CO2 concentrations when warmed. 3. The difference in CO2 concentration resulting from the depth manipulation was due to varying loss rates of particulate carbon to the sediments. There was a strong negative correlation between CO2 and sedimentation rates in the deep mesocosms suggesting that high particulate carbon loss to the sediments lowered the CO2 concentration in the water column. There was no correlation between CO2 and sedimentation rates observed for shallow mesocosms suggesting enhanced carbon regeneration from the sediments was maintaining higher CO2 concentrations in the water column. 4. Relationships between CO2 and algal concentrations indicate that the reduction in CO2 concentrations resulting from warming is due to increased per capita algal turnover rates depleting CO2 in the water column. Our results suggest that the carbon dynamics and CO2 flux of shallow systems will be affected more by climate warming than deep systems and the net effect of warming is to increase CO2 uptake. [source] hnRNP K interacts with RNA binding motif protein 42 and functions in the maintenance of cellular ATP level during stress conditionsGENES TO CELLS, Issue 2 2009Toshiyuki Fukuda Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a conserved RNA-binding protein that is involved in multiple processes of gene expression, including chromatin remodeling, transcription, RNA splicing, mRNA stability and translation, together with diverse groups of molecular partners. Here we identified a previously uncharacterized protein RNA binding motif protein 42 (RBM42) as hnRNP K-binding protein. RBM42 directly bound to hnRNP K in vivo and in vitro. RBM42 also directly bound to the 3, untranslated region of p21 mRNA, one of the target mRNAs for hnRNP K. RBM42 predominantly localized within the nucleus and co-localized with hnRNP K there. When cells were treated with agents, puromycin, sorbitol or arsenite, which induced the formation of stress granules (SGs), cytoplasmic aggregates of stalled translational pre-initiation complexes, both hnRNP K and RBM42 localized at SGs. Depletion of hnRNP K by RNA interference decreased cellular ATP level following release from stress conditions. Simultaneous depletion of RBM42 with hnRNP K enhanced the effect of the hnRNP K depletion. Our results indicate that hnRNP K and RBM42 are components of SGs and suggest that hnRNP K and RBM42 have a role in the maintenance of cellular ATP level in the stress conditions possibly through protecting their target mRNAs. [source] Controls on old and new water contributions to stream flow at some nested catchments in Vermont, USAHYDROLOGICAL PROCESSES, Issue 3 2002James B. Shanley Abstract Factors controlling the partitioning of old and new water contributions to stream flow were investigated for three events in four catchments (three of which were nested) at Sleepers River Research Watershed in Danville, Vermont. In the 1993 snowmelt period, two-component isotopic hydrograph separations showed that new water (meltwater) inputs to the stream ranged widely from 41 to 74%, and increased with catchment size (41 to 11 125 ha) (with one exception) and with open land cover (0,73%). Peak dissolved organic carbon concentrations and relative alkalinity dilution in stream water ranked in the same order among catchments as the new water fractions, suggesting that new water followed shallow flow paths. During the 1994 snowmelt, despite similar timing and magnitude of melt inputs, the new-water contribution to stream flow ranged only from 30 to 36% in the four catchments. We conclude that the uncommonly high and variable new water fractions in streamwater during the 1993 melt were caused by direct runoff of meltwater over frozen ground, which was prevalent in open land areas during the 1993 winter. In a high-intensity summer rainstorm in 1993, new water fractions were smaller relative to the 1993 snowmelt, ranging from 28 to 46%, but they ranked in the identical catchment order. Reconciliation of the contrasting patterns of new,old water partitioning in the three events appears to require an explanation that invokes multiple processes and effects, including: 1.topographically controlled increase in surface-saturated area with increasing catchment size; 2.direct runoff over frozen ground; 3.low infiltration in agriculturally compacted soils; 4.differences in soil transmissivity, which may be more relevant under dry antecedent conditions. These data highlight some of the difficulties faced by catchment hydrologists in formulating a theory of runoff generation at varying basin scales. Copyright © 2002 John Wiley & Sons, Ltd. [source] Child, Caregiver, and Temperament Contributions to Infant Joint AttentionINFANCY, Issue 4 2003Amy Vaughan Little is known about variables that may contribute to individual differences in infant joint attention, or the coordination of visual attention with a social partner. Therefore, this study examined the contributions of caregiver behavior and temperament to infant joint attention development between 9 and 12 months. Data were collected from 57 infants using a caregiver,infant paradigm, an infant,tester paradigm, and a parent report of infant temperament. Nine-month measures of caregiver scaffolding and infant initiating joint attention (IJA) with testers were significantly related to 12-month infant IJA with testers. A temperament measure of positive emotional reactivity was related to 9-month IJA, and a measure of negative emotional reactivity was related to 12-month IJA. Temperament and caregiver scaffolding measures, however, were not associated with the development of infant responding to joint attention. These results further the understanding of the multiple processes that contribute to joint attention development in infancy, and support the hypothesis that initiating and responding measures tap different aspects of joint attention development. [source] Failures of the state failure debate: Evidence from the Somali territories,JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 1 2009Tobias Hagmann Abstract Much of the current literature on state failure and collapse suffers from serious conceptual flaws. It ignores the variegated types of empirical statehood that exist on the ground, it conflates the absence of a central government with anarchy, it creates an unhelpful distinction between ,accomplished' and ,failed' states, and it is guided by a teleological belief in the convergence of all nation-states. Particularly African states figure prominently in this debate and are frequently portrayed in almost pathological terms. Proposing a comparative analysis of politics in the Somali inhabited territories of the Horn of Africa, this article challenges state failure discourses on both theoretical and empirical grounds. We draw attention to the multiple processes of state-building and forms of statehood that have emerged in Somalia, and the neighbouring Somalia region of Ethiopia, since 1991. The analysis of the different trajectories of these Somali political orders reveals that state formation in Africa contradicts central tenets of the state failure debate and that external state-building interventions should recognise and engage with sub-national political entities. Copyright © 2008 John Wiley & Sons, Ltd. [source] Inclusion trail patterns in porphyroblasts from the Foothills Terrane, California: a record of orogenesis or local strain heterogeneity?JOURNAL OF METAMORPHIC GEOLOGY, Issue 4 2001S. R. Paterson Abstract A major problem with the current use of porphyroblast,matrix microstructural relationships to infer orogenic histories, such as multiple orthogonal orogenic events, is that other evidence for these events is typically lacking. For example, a comparison of regional relationships and local structures formed in and adjacent to porphyroblasts present in contact aureoles in the Foothills Terrane, Sierra Nevada, California, shows that: (1) except in shear zones, contact aureoles and local zones along lithological contacts, the Foothills Terrane has a single regional cleavage, although locally formed by multiple processes; (2) the regional cleavage and locally developed porphyroblast inclusion trails have variable orientations, and neither dataset supports the formation of dominantly subhorizontal and subvertical cleavages in this orogen; (3) structural and metamorphic heterogeneities occur at all scales and can markedly affect inclusion trail patterns in porphyroblasts; (4) complex porphyroblast growth features and internal inclusion trail patterns can form in porphyroblasts that grow during short time intervals in contact aureoles, indicating that local complexity in porphyroblasts does not imply regional complex ty. Because of these conclusions, multiple datasets, rather than data acquired only from porphyroblasts, should be considered when attempting to understand the evolution of orogens. Furthermore, using microstructural information preserved only in porphyroblasts to infer orogenic processes and plate motions is generally unjustified. [source] A C1 microkinetic model for methane conversion to syngas on Rh/Al2O3AICHE JOURNAL, Issue 4 2009Matteo Maestri Abstract A microkinetic model capable of describing multiple processes related to the conversion of natural gas to syngas and hydrogen on Rh is derived. The parameters of microkinetic models are subject to (intrinsic) uncertainty arising from estimation. It is shown that intrinsic uncertainty could markedly affect even qualitative model predictions (e.g., the rate-determining step). In order to render kinetic models predictive, we propose a hierarchical, data-driven methodology, where microkinetic model analysis is combined with a comprehensive, kinetically relevant set of nearly isothermal experimental data. The new, thermodynamically consistent model is capable of predicting several processes, including methane steam and dry reforming, catalytic partial oxidation, H2 and CO rich combustion, water-gas shift and its reverse at different temperatures, space velocities, compositions and reactant dilutions, using the measured Rh dispersion as an input. Comparison with other microkinetic models is undertaken. Finally, an uncertainty analysis assesses the effect of intrinsic uncertainty and catalyst heterogeneity on the overall model predictions. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Regulation of In Situ Skeletal Muscle Arteriolar Tone: Interactions Between Two ParametersMICROCIRCULATION, Issue 6 2002JEFFERSON C. FRISBEEArticle first published online: 26 JAN 2010 ABSTRACT Objective: The growing understanding of the complexity of mechanisms regulating arteriolar tone demands that a systematic determination of how these processes interact to alter diameter be undertaken. This study examined how five mediators of skeletal muscle distal arteriolar tone [adenosine concentration, oxygen content, ,-adrenergic activation (norepinephrine), intravascular pressure and wall shear rate], taken two parameters at a time, interact to regulate vessel diameter. Methods: The reactivity of distal arterioles of in situ rat cremaster muscle after alterations in each of the above mediators was assessed. In addition, arteriolar responses to all two-parameter combinations were evaluated to determine the effect of altered environment on vascular reactivity to stimuli. Results: Arteriolar dilation to adenosine was unaltered by changes in other parameters. In contrast, wall shear rate-induced arteriolar dilation was impaired by 60,88% after increases in the other parameters. Myogenic reactivity was reduced by 28% with elevated O2 and by 65% with norepinephrine (because of vessel closure) and was impaired by 89% with elevated adenosine. O2 -induced arteriolar reactivity was impaired by 56% with increased adenosine and by 44% with increased norepinephrine concentration but was largely unaffected by elevated intravascular pressure. Adrenergic reactivity was attenuated with elevated intravascular pressure (by 69%) and O2 (by 54%) because of vessel closure but was unaltered with elevated adenosine. Conclusions: These data suggest that (1) individual mediators contributing to the regulation of arteriolar tone exist within a hierarchy of importance and (2) mechanisms regulating arteriolar tone can be impacted by unidentified alterations in other processes. Ongoing investigation into interactions between multiple processes regulating arteriolar tone will allow for a more integrated understanding of how microvessels regulate their diameter. [source] Silibinin inhibits the invasion of human lung cancer cells via decreased productions of urokinase-plasminogen activator and matrix metalloproteinase-2,MOLECULAR CARCINOGENESIS, Issue 3 2004Shu-Chen Chu Abstract Cancer metastasis, involving multiple processes and various cytophysiological changes, is a primary cause of cancer death and may complicate the clinical management, even lead to death. Silibinin is a flavonoid antioxidant and wildly used for its antihepatotoxic properties and recent studies have revealed pleiotropic anticancer and antiproliferative capabilities of silibinin. In this study, we first observed that silibinin exerted a dose- and time-dependent inhibitory effect on the invasion and motility, but hardly on the adhesion, of highly metastatic A549 cells in the absence of cytotoxicity. To look at the precise involvement of silibinin in cancer metastasis, A549 cells were treated with silibinin at various concentrations, up to 100 ,M, for a defined period and then subjected to gelatin zymography, casein zymography and Western blot to investigate the impacts of silibinin on metalloproteinase-2 (MMP-2), urokinase plasminogen activator (u-PA), and tissue inhibitor of metalloproteinase-2 (TIMP-2), respectively. The results showed that a silibinin treatment may decrease the expressions of MMP-2 and u-PA in a concentration- and time-dependent manner and enhance the expression of TIMP-2. Further analysis with semi-quantitative RT-PCR showed that silibinin may regulate the expressions of MMP-2 and u-PA on the transcriptional level while on the translational or post-translational level for TIMP-2. © 2004 Wiley-Liss, Inc. [source] 3-Ketosteroid 9,-hydroxylase is an essential factor in the pathogenesis of Mycobacterium tuberculosisMOLECULAR MICROBIOLOGY, Issue 1 2010Yanmin Hu Summary Mycobacterium tuberculosis H37Rv contains the kshA (Rv3526) and kshB (Rv3571) genes, encoding 3-ketosteroid 9,-hydroxylase (KSH). Consistent with their predicted roles, the ,kshA and ,kshB deletion mutants of M. tuberculosis H37Rv were unable to use cholesterol and 4-androstene-3,17-dione as primary carbon and energy sources. Interestingly, ,kshA and ,kshB mutants were also unable to metabolize the steroid substrate 5,-androstane-3,17-dione, whereas wild-type M. tuberculosis H37Rv could. The deletion of either of these genes lead to rapid death of the microorganism in murine infection models and in macrophages, showing that kshA and kshB are essential factors for M. tuberculosis pathogenesis. Penta-acylated trehalose (PAT) biosynthesis was altered in the ,kshB mutant, but not the ,kshA mutant. The ,kshB mutant synthesizes all other types of lipids. The ,kshB mutant had a thickened outer layer in its cell wall. KshB thus appears to be involved in multiple processes, probably as a reductase of different oxygenases. We conclude that an impaired 3-ketosteroid 9,-hydroxylase activity is the cause of the highly attenuated phenotype of our M. tuberculosis H37Rv mutants. [source] Landscape of the hnRNP K protein,protein interactomePROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 8 2006Micha, Mikula Abstract The heterogeneous nuclear ribonucleoprotein K is an ancient RNA/DNA-binding protein that is involved in multiple processes that compose gene expression. The pleiotropic action of K protein reflects its ability to interact with different classes of factors, interactions that are regulated by extracellular signals. We used affinity purification and MS to better define the repertoire of K protein partners. We identified a large number of new K protein partners, some typically found in subcellular compartments, such as plasma membrane, where K protein has not previously been seen. Electron microscopy showed K protein in the nucleus, cytoplasm, mitochondria, and in vicinity of plasma membrane. These observations greatly expanded the view of the landscape of K protein,protein interaction and provide new opportunities to explore signal transduction and gene expression in several subcellular compartments. [source] A partition experimental design for a sequential process with a large number of variablesQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 5 2007Leonard A. Perry Abstract Statistically designed experiments provide a systematic approach to study and analyze the effects of multiple factors on process performance. In order to improve the performance across an organization, one must investigate multiple processes from supplier to customer. Partition experimental designs provide a design to model several sequential processes simultaneously. The partition design provides the investigator with an efficient design where potential cost and time constraints exist. That is, partition designs are applicable when runs are costly and a large number of variables exist in the serial process. In this paper, we present the application of partition designs using 10 factors in a simulated case study. The design and analysis procedures are discussed, as well as the benefits. Copyright © 2006 John Wiley & Sons, Ltd. [source] Rapid actions of oestrogen on gonadotropin-releasing hormone neurons; from fantasy to physiology?THE JOURNAL OF PHYSIOLOGY, Issue 21 2009Allan E. Herbison Oestradiol (E2) exerts critical homeostatic feedback effects upon gonadotropin-releasing hormone (GnRH) neurons to maintain fertility. In the female, E2 has both negative and positive feedback actions to suppress and stimulate GnRH neuron activity at different times of the ovarian cycle. This review summarizes reported rapid E2 effects on native embryonic and adult GnRH neurons and attempts to put them into a physiological perspective. Oestrogen has been shown to rapidly modulate multiple processes in embryonic and adult GnRH neurons including intracellular calcium levels, electrical activity and specific second messenger pathways, as well as GnRH secretion itself. Evaluation of in vivo data suggests that there is no essential role for rapid E2 actions in the positive feedback mechanism but that they may comprise part of the negative feedback pathway. Adult GnRH neurons are only likely to be exposed to E2 from the gonads via the circulation with appropriate physiological E2 concentrations in the rodent being 10,50 pm for negative feedback ranging up to 400 pm for positive feedback. Although most studies to date have examined the effects of supraphysiological E2 levels on GnRH neurons, there is accumulating evidence that rapid E2 actions may have a physiological role in suppressing GnRH neuron activity. [source] Interactions between multiple sources of short-term plasticity during evoked and spontaneous activity at the rat calyx of HeldTHE JOURNAL OF PHYSIOLOGY, Issue 13 2008Matthias H. Hennig Sustained activity at most central synapses is accompanied by a number of short-term changes in synaptic strength which act over a range of time scales. Here we examine experimental data and develop a model of synaptic depression at the calyx of Held synaptic terminal that combines many of these mechanisms (acting at differing sites and across a range of time scales). This new model incorporates vesicle recycling, facilitation, activity-dependent vesicle retrieval and multiple mechanisms affecting calcium channel activity and release probability. It can accurately reproduce the time course of experimentally measured short-term depression across different stimulus frequencies and exhibits a slow decay in EPSC amplitude during sustained stimulation. We show that the slow decay is a consequence of vesicle release inhibition by multiple mechanisms and is accompanied by a partial recovery of the releasable vesicle pool. This prediction is supported by patch-clamp data, using long duration repetitive EPSC stimulation at up to 400 Hz. The model also explains the recovery from depression in terms of interaction between these multiple processes, which together generate a stimulus-history-dependent recovery after repetitive stimulation. Given the high rates of spontaneous activity in the auditory pathway, the model also demonstrates how these multiple interactions cause chronic synaptic depression under in vivo conditions. While the magnitude of the depression converges to the same steady state for a given frequency, the time courses of onset and recovery are faster in the presence of spontaneous activity. We conclude that interactions between multiple sources of short-term plasticity can account for the complex kinetics during high frequency stimulation and cause stimulus-history-dependent recovery at this relay synapse. [source] Interest of industrial actors in biorefinery concepts in EuropeBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 3 2009Klaus Menrad Abstract To satisfy the rising demand for agricultural and forestry products it is becoming more and more important to use biomass as efficiently as possible. One way of achieving that goal is to implement biorefinery systems in which biomass can be utilized entirely by conversion through multiple processes into a number of valuable products. To pursue the implementation of biorefinery systems, it is important to know to what extent the industry is interested in such concepts. This perspective deals with the results of a cross-European survey investigating the interests of potential industrial actors in biorefinery concepts. A high resonance was identified amongst companies belonging to the biofuels industry; companies active in this sector, therefore, could possibly provide access to further integrated concepts. On the whole, the results reflect a very positive attitude toward biorefinery concepts. But there are also problems with respect to the political and legal framework; policy and legislation may be required to establish stable framework conditions and provide planning security for investment decisions. Oilseed and lignocellulosic feedstock is primarily utilized within the surveyed companies; fuel, heat and power are the primary products produced from biomass. Additionally, the survey showed that biorefinery concepts are highly influenced by aspects concerning regional value chains. On the upstream side ,feedstock issues' appear to be especially important for biorefineries. In general, sustainability aspects are considered to be a benefit of biorefinery concepts. This suggests opportunities for the design of marketing and communication strategies based on ecological aspects of biorefinery implementation. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] The perplexing functions and surprising origins of Legionella pneumophila type IV secretion effectorsCELLULAR MICROBIOLOGY, Issue 10 2009Irina S. Franco Summary Only a limited number of bacterial pathogens evade destruction by phagocytic cells such as macrophages. Legionella pneumophila is a Gram-negative ,-proteobacterial species that can infect and replicate in alveolar macrophages, causing Legionnaires' disease, a severe pneumonia. L. pneumophila uses a complex secretion system to inject host cells with effector proteins capable of disrupting or altering the host cell processes. The L. pneumophila effectors target multiple processes but are essentially aimed at modifying the properties of the L. pneumophila phagosome by altering vesicular trafficking, gradually creating a specialized vacuole in which the bacteria replicate robustly. In nature, L. pneumophila is thought to parasitize free-living protists, which may have selected for traits that promote virulence of L. pneumophila in humans. Indeed, many effector genes encode proteins with eukaryotic domains and are likely to be of protozoan origin. Sustained horizontal gene transfer events within the protozoan niche may have allowed L. pneumophila to become a professional parasite of phagocytes, simultaneously giving rise to its ability to infect macrophages, cells that constitute the first line of cellular defence against bacterial infections. [source] | |||||||||||||||||||||||||