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Questions: Phylogenetic analyses provide important insights in the study of biological invasions. Previous studies have shown contrasting effects of alien species on the phylogenetic structure of recipient communities. In this study, we focus on two riparian plant communities with contrasting natural disturbance regimes: riparian forests and river bar communities. We ask whether these communities differ in alpha diversity and degree of plant invasion. Further, are the phylogenetic diversity (PD) and structure of these habitats related to the level of plant invasion? Location: Northern Spain. Methods: We determined level of plant invasion in forest and river bar vegetation plots, and calculated PD using mean pairwise distance (MPD) and mean nearest taxon distance (MNTD). We applied null models to analyse the phylogenetic structure of plots, and we tested whether inclusion of alien plant species was associated with differences in observed phylogenetic structure. Results: River bar plots experienced more invasion than forest plots, but the level of invasion was only related to the PD of native species in forests. Most plots had random phylogenetic structure, with a minority of plots tending to phylogenetic overdispersion in forests and to phylogenetic clustering in river bars. MPD increased with the inclusion of alien plant species in forest plots, suggesting phylogenetic overdispersion, while no such pattern was detected with MNTD. MPD increased slightly with increasing invasion in river bar plots, suggesting reduced clustering, while MNTD values decreased with increasing invasion, suggesting the opposite trend. Conclusions: Invasion by alien plants is differentially associated with phylogenetic structure in riparian habitats with different disturbance levels. Our results contrast with those of previous studies of plant invasion of riparian communities, which suggests geographic and ecological variation in the relationship between invasion and phylogenetic community structure in riparian systems. Research is needed to identify the causal factors underlying this variation. [ABSTRACT FROM AUTHOR]

Aim: Previous studies have shown that phylogenetic divergence (i.e. the average phylogenetic displacement between species in a community) is highly sensitive to the underlying branching patterns of phylogenies, suggesting that there is a need to integrate both facets of phylogenic information to obtain a better understanding of assemblage structure. Here, we formally conceptualize the three fundamental branching patterns that can drive phylogenetic divergence, and propose a method to identify their signature in the communities based on the mean pairwise distance (MPD) metric. Location: Global. Taxa: All. Methods: Our approach consists of the joint interpretation of two MPD‐derived metrics that summarize the differential contribution of individual phylogenetic branches to the observed divergence, which serves to evaluate to what extent the later emerges from contrasting branching patterns. We conduct simulation analyses to compare our two metrics with eight classical descriptors of phylogenetic structure, and use multi‐strata tropical plant communities along a gradient of land use intensity (LUI) to further illustrate our method. Results: As expected, our metrics correlated to some extent with the classical descriptors of phylogenetic structure, although the relationships were complex and varied systematically with species richness and the specific combination of metric values considered. Consequently, the information provided by our two indexes was only partially captured by their most correlated classical descriptors. We detected differential signatures of the fundamental branching patterns in our real‐world dataset, either across vegetation strata and also within strata along the LUI gradient, which provided greater insight into potential assembly mechanisms. Main conclusions: While the sole use of phylogenetic divergence may lead to spurious interpretations in eco‐phylogenetic studies, our approach can help to obtain a better understanding of assemblage structure by systematically analyzing phylogenetic divergence in the light of its fundamental branching patterns. [ABSTRACT FROM AUTHOR]

Phylogenetic and species‐based taxonomic descriptions of community structure may provide complementary information about the mechanisms driving community assembly across different environments. Environmental filtering may have similar effects on taxonomic and phylogenetic diversity under the assumption of niche conservatism, whereas competitive exclusion could produce contrasting patterns in these diversity metrics. In grassland restorations, these diversity patterns might then reveal potential assembly mechanisms underlying the impacts of restoration and management conditions on community structure.We compared plant community structure (alpha diversity, composition, and within‐site beta diversity) from both phylogenetic and taxonomic perspectives. Using surveys from 120 tallgrass prairie restorations in four regions of the Midwestern United States, we examined the effects of four potential drivers or environmental gradients: precipitation in the first year of restoration, seed mix richness, time since last prescribed fire, and restoration age, and included soil conditions as a covariate.First‐year precipitation influenced taxonomic community structure, but had weak effects on phylogenetic diversity and composition. Similarly, greater seed mix richness increased taxonomic diversity but did not influence phylogenetic diversity. Taxonomic, but not phylogenetic, diversity generally was lower in older restorations and those with a longer time since the last prescribed fire. These drivers consistently explained more variation in taxonomic than phylogenetic diversity and composition, perhaps in part because species turnover was largely among related species, producing weak impacts on phylogenetic community measures.An impact of precipitation on taxonomic but not phylogenetic diversity suggests that there may not be large differences in drought tolerance among clades that would cause phylogenetic patterns to arise from this environmental filter. Declining taxonomic diversity but not phylogenetic diversity is consistent with competitive exclusion as an assembly mechanism when competition is strongest between related species.Synthesis. This research shows how studying taxonomic and phylogenetic diversity of ecosystem restorations can inform plant community ecology and help natural resource managers better predict the outcomes of restoration actions and management. [ABSTRACT FROM AUTHOR]

Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2,4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with ( R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with ( R)-MPD and ( RS)-MPD the crystal contacts are made by ( R)-MPD, demonstrating that there is preferential interaction between lysozyme and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization. [ABSTRACT FROM AUTHOR]

The phase diagram for the crystallization of L-asparaginase II including the metastable zone width (MZW), in the presence of PEG6000 and ethanol, respectively, has been studied by an online turbidity technique out of the crystallization in solution (see part I of this work ). Here this paper describes a further investigation on constructing a phase diagram including MZW for the crystallization of L-asparaginase II with a different precipitant agent of 2-methyl-2, 4-pentandiol (MPD). Along with the phase diagram, the single crystal X-ray data were successfully collected at 100K from a crystal formed in the presence of 26% (v/v) MPD. The crystals indicate an orthorhombic form and belong to the space group of P212121 with the unit cell parameters a = 93.9, b = 125.77, c = 151.75Å. The crystal diffracted up to a resolution of 2.88 Å. [ABSTRACT FROM AUTHOR]

Ph-negative chronic myeloproliferative disorders (CMPD) are characterized by constitutive Janus kinase-signal transducer and activator of transcription (JAK-STAT) activation. SOCS3, SOCS1 and PTPN6 ( SHP1) are negative regulators of the JAK-STAT pathway. We investigated epigenetic and genetic inactivation of SOCS3, SOCS1 and PTPN6 in 112 CMPD and 20 acute myeloid leukaemia (AML) post-CMPD. SOCS3 methylation occurred at high frequency in both CMPD (46/112; 41·1%) and AML post-CMPD (10/17; 58·8%) and was associated with transcriptional silencing. In contrast, methylation of SOCS1 and PTPN6 was observed in only a fraction of CMPD (15/112, 13·4% for SOCS1; and 8/112, 7·1% for PTPN6) and AML post-CMPD (3/20, 15% for SOCS1; and 1/20, 5% for PTPN6). No somatic mutations of SOCS1 were found in CMPD. SOCS3, SOCS1 and PTPN6 methylation occurred in both JAK2V617F-positive (35·1% for SOCS3; 14·9% for SOCS1; 8·1% for PTPN6) and JAK2V617F-negative (57·1% for SOCS3; 14·3% for SOCS1; and 9·5% for PTPN6) CMPD. These data indicate that methylation of SOCS3 and, to a lesser extent, SOCS1 and PTPN6 is a frequent event in both JAK2V617F-positive and -negative CMPD and may act as an alternative or complementary mechanism to JAK2 mutations, enhancing cytokine signal transduction. The frequent inactivation of SOCS3 is a novel finding in CMPD with potential implications for the molecular pathology of these disorders. [ABSTRACT FROM AUTHOR]

The effects of a number of cryoprotectants on the kinetic and structural properties of glycogen phosphorylase b have been investigated. Kinetic studies showed that glycerol, one of the most commonly used cryoprotectants in X-ray crystallographic studies, is a competitive inhibitor with respect to substrate glucose-1-P with an apparent Ki value of 3.8% (v/v). Cryogenic experiments, with the enzyme, have shown that glycerol binds at the catalytic site and competes with glucose analogues that bind at the catalytic site, thus preventing the formation of complexes. This necessitated a change in the conditions for cryoprotection in crystallographic binding experiments with glycogen phosphorylase. It was found that 2-methyl-2,4-pentanediol (MPD), polyethylene glycols (PEGs) of various molecular weights, and dimethyl sulfoxide (DMSO) activated glycogen phosphorylase b to different extents, by stabilizing its most active conformation, while sucrose acted as a noncompetitive inhibitor and elethylene glycol as an uncompetitve inhibitor with respect to glucose-1-P. A parallel experimental investigation by X-ray crystallography showed that, at 100 K, both MPD and DMSO do not bind at the catalytic site, do not induce any significant conformational change on the enzyme molecule, and hence, are more suitable cryoprotectants than glycerol for binding studies with glycogen phosphorylase. [ABSTRACT FROM PUBLISHER]

The M-sequence (maximum length sequence) is often used as a ranging signal in radar and other systems. This paper considers the case where an M sequence ranging signal is detected by an MPD (matched pulse detector), which is a digital correlator, and analyzes the probabilities for miss detection and for false detection due to bit error. Previously, this correlation function has not been derived analytically. In this paper, a procedure is presented where the threshold for the miss detection and false detection probabilities is determined by a simulation result for the correlator. An experiment is attempted in which a single M-sequence is detected in satellite communication using VSAT (very small aperture terminal). It is shown that the experimental results and analysis almost agree for a single M-sequence with a 31-bit code length. © 1998 Scripta Technica. Electron Comm Jpn Pt 1, 82(2): 82–89, 1999 [ABSTRACT FROM AUTHOR]