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• Lycopodium represents a phylogenetically distinct clade of basal vascular plants with anatomical characters that have no parallel in other lineages. Thus, knowledge of lycopod structure and development may reveal important information about the common ancestors of all vascular plants. Here we report the unique architecture of the conducting system in Lycopodium annotinum and Lycopodium clavatum. • Based on multiple series of anatomical sections, we reconstructed spatial relationships between microphylls and the stelar system. • Analysis revealed that protoxylem ribs (PXR) were vertical, regardless of type of phyllotaxis, and their numbers were variable. Microphyll traces (MTr) were randomly distributed between ribs, resulting in the absence of defined sympodia and varied lengths of MTr. Dichotomous branching contributed to additional features, for example occurrence of mesarch protoxylem, affecting stele structure and PXR numbers. • Our data showed limited interrelationships between lycopod vasculature and microphyll phyllotaxis. This may suggest that both systems developed independently, then evolved together to form the integrated supply system. Thus vasculature in extant lycophytes may be less functionally efficient than in seed plants, where consistent leaf-trace lengths guarantee predictable energy utilization during ontogeny. Differences may result from the phylogenetically different origin of microphylls, and the level of vascular complexity. [ABSTRACT FROM AUTHOR]

Gynoecia of the Arabidopsis mutant sty1-1 display abnormal style morphology and altered vascular patterning. These phenotypes, which are enhanced in the sty1-1 sty2-1 double mutant, suggest that auxin homeostasis or signalling might be affected by mutations in STY1 and STY2, both members of the SHI gene family. Chemical inhibition of polar auxin transport (PAT) severely affects the apical–basal patterning of the gynoecium, as do mutations in the auxin transport/signalling genes PIN1, PID and ETT. Here we show that the apical–basal patterning of sty1-1 and sty1-1 sty2-1 gynoecia is hypersensitive to reductions in PAT, and that sty1-1 enhances the PAT inhibition-like phenotypes of pin1-5, pid-8 and ett-1 gynoecia. Furthermore, we show that STY1 activates transcription of the flavin monooxygenase-encoding gene THREAD/YUCCA4, involved in auxin biosynthesis, and that changes in expression of STY1 and related genes lead to altered auxin homeostasis. Our results suggest that STY1 and related genes promote normal development of the style and affect apical–basal patterning of the gynoecium through regulation of auxin homeostasis. [ABSTRACT FROM AUTHOR]

The article discusses the biotrophic interaction between Lotus japonicus and the rust fungus Uromyces loti. The symbiotic relationship is probably the most important plant-fungus interaction. One common feature of biotrophic interactions is the formation of elaborate intracellular accommodation structures that maintain an intimate coexistence of both fungal and plant cells over a prolonged period. A genetic approach is used in a study to unravel the overlap between mutualistic and parasitic biotrophy.

The article highlights the issues that emerged during the 14th New Phytologist Symposium held at the Royal Society in London, England in January 2006. The symposium addressed the broad goal of ecological development. Ecological development aims to close the gap between mechanisms and ecology, and provide a genuinely integrated view of plant development in its real environmental context. Knowledge of genetic mechanisms may be essential in understanding the degree of correlation or independence of plant responses to different environmental factors.

The ability of a genotype to change its phenotype was once considered rather a nuisance – making it difficult to define a genotype. This led to the idea that there was a problem called ‘instability’. But quite early it was recognized that stability was under genetic control, and was a character like other attributes of an individual. From this realization came the idea that there were two sides to the character of ‘instability’, and that the ability to change could be important. This ability was thus given the title of ‘plasticity’. Once recognized, it became clear from surveys of different species and populations that plasticity can (i) be a complex character, and (ii) be selected to fit species to the particular demands of different environments. For plants, which cannot meet variations in environment like animals by behavioural responses, phenotypic plasticity can be very important. Plants should therefore be valuable tools for unravelling the mechanisms of plasticity whilst also demonstrating its contribution to fitness experimentally. We ought also to be able to demonstrate that appropriate genetic variability is available through which complex responses can be built up by selection. Genes must exist not only to determine character means, but also to determine character response, which adds interesting complexity to our ideas about evolution. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has seen increasing use across all sectors, as enabled by increasing volumes of data, greater computing power and novel algorithm architectures. Machine learning (ML) encompasses a group of AI methods by which computers can identify patterns and relationships between data (such as radiological images or blood tests) and outcomes of interest. Convolutional neural networks (CNNs) are specialized ML methods, excelling at imaging analysis, which may support assessment of respiratory disease on chest X-ray or CT scan. [Extracted from the article]

Summary 1I. Introduction 1II. The shoot apical meristem: the creation of a field of cells from which leaves can be formed 2III. Patterning: the selection of leaf initiation site 2IV. Morphogenesis: the initial stages of leaf formation 4V. Differentiation and determination: transcriptional networks controlling determinancy 6VI. The elaboration of leaf form 6VII. Early steps in leaf histogenesis 7VIII. Later steps in leaf differentiation: epidermal cell fate 8IX. Compound and simple leaves: variation on a theme? 9X. Changes in leaf form: developmental and environmental influences 9XI. A model of leaf formation 9 Acknowledgements 10 References 10The formation of a leaf is a basic aspect of plant development. This review provides an overview of our present understanding of the process from initiation to the final form of the leaf. Molecular genetic and cell biology approaches have yielded significant advances in this area, adding not only to our knowledge of leaf development but also to fundamental principles in plant biology. These principles will be highlighted, as well as areas where our understanding is still incomplete, in particular the problem of coordinating the multifaceted steps involved in the generation of the leaf structure.New Phytologist(2004)doi: 10.1111/j.1469-8137.2004.01292.x© New Phytologist(2004) [ABSTRACT FROM AUTHOR]

This article presents information on Vienna Symposium on rate responsive pacing which will be held from September 27-29, 1989 in Vienna, Austria and is organized by the 2nd Department of Surgery University of Vienna. The program has been divided into several sessions. Some of the abstracts are about the hemodynamic benefit of AV synchrony during low levels of exercise which has not previously been addressed. Most comparisons of single and dual chamber modes have been at rest and peak exercise which is rarely, if ever, attained.

The article presents a list of authors' names who gave their valuable contribution towards the journal "Pacing and Clinical Electrophysiology." Some of the authors are R.T. Steinman, A. Stertman, S. Stevens, G. Stix, B. Stobierska, P. Stojanov, K. Stokes, N. Stolf, C. Storti, and S.A. Strickberger.

Presents an author index for the July 1993 issue of the periodical "Pace".

Discusses abstracts of articles concerning cardiology. “Clinical Experience of Application of Physiological Pacemakers in 20 Cases,” by Jiang Shisen and colleagues; “Echocardiography for the Evaluation of Optimal AV Intervals in Dual Chamber Pacing,” by Du Xueping and colleagues; “Electrophysiological Characteristics of Atrium in Patients Implanted With Physiologic Pacemaker,” by Shunsuke Ogura and colleagues.

The article provides a quantitative analysis of the process of capitulum growth and the gradual but controlled process by which elements within the capitulum become destined to form individual flowers. The data provide a foundation for the modelling of flower formation and for linking the observed parameters of floral morphogenesis with the wealth of molecular data on organogenesis in plants. An analysis of auxin flux and distribution during leaf initiation is also presented. The situation in the capitulum may be linked with the spatial and temporal control of factors specific to flower formation.

The article highlights the XII International Congress on Molecular Plant-Microbe Interactions in Yucatán, Mexico in December 2005. The aim of the meetings is to present data at the forefront of research over a wide field of interactions between plants, fungi, bacteria, viruses and nematodes. The emphasis is on the genetic and molecular analysis of the processes under study. Several of the speakers at the conference focused on nonhost resistance and the importance of pathogen-associated molecular pattern perception and transduction.

The International League against Epilepsy (ILAE) proposed a diagnostic scheme for psychogenic non‐epileptic seizure (PNES). The debate on ethical aspects of the diagnostic procedures is ongoing, the treatment is not standardized and management might differ according to age group. The objective was to reach an expert and stakeholder consensus on PNES management. A board comprising adult and child neurologists, neuropsychologists, psychiatrists, pharmacologists, experts in forensic medicine and bioethics as well as patients' representatives was formed. The board chose five main topics regarding PNES: diagnosis; ethical issues; psychiatric comorbidities; psychological treatment; and pharmacological treatment. After a systematic review of the literature, the board met in a consensus conference in Catanzaro (Italy). Further consultations using a model of Delphi panel were held. The global level of evidence for all topics was low. Even though most questions were formulated separately for children/adolescents and adults, no major age‐related differences emerged. The board established that the approach to PNES diagnosis should comply with ILAE recommendations. Seizure induction was considered ethical, preferring the least invasive techniques. The board recommended looking carefully for mood disturbances, personality disorders and psychic trauma in persons with PNES and considering cognitive‐behavioural therapy as a first‐line psychological approach and pharmacological treatment to manage comorbid conditions, namely anxiety and depression. Psychogenic non‐epileptic seizure management should be multidisciplinary. High‐quality long‐term studies are needed to standardize PNES management. Click here to view the accompanying paper in this volume. [ABSTRACT FROM AUTHOR]

Ethanol is a precursor of ethyl esters in olive oil. Its presence is generally ascribed to microbial degradation of damaged olives. At the same time, it is an anaerobic metabolite that naturally accumulates in olive fruit during ripening. As the possible link with olive processing is poorly studied, this laboratory‐scale experiment measures gaseous ethanol in the headspace above olive paste malaxated in sealed conditions. Malaxation take place in the presence or absence of oxygen, using sanitized or untreated olives. The findings show that ethanol accumulates in the headspace in oxygenated trials, reaching roughly 80 μmol kg−1 of olive paste. Under anoxic conditions ethanol accumulation is ten times higher, while olive treatment is not significant. Ethanol kinetics during malaxation are modeled as a biexponential system in which two components are simultaneously present, originating from parallel reactions at different constant rates. The first is the ethanol present in the olives and gradually released in the headspace. The second is ethanol neoformation under anoxic conditions. Under oxygenated conditions, the first component predominates, while under anoxic conditions, the opposite holds. Practical Application: Online monitoring of gaseous ethanol above olive paste during malaxation could easily be implemented in olive oil processing plants. Ethanol kinetics could indicate the presence of unwanted anoxic conditions and help in setting appropriate oxygen levels in the kneaded paste. Future studies may find a link between ethanol kinetics in the malaxation headspace, and the occurrence of ethyl esters in oils. If this is the case, operators would be able to fine‐tune the process to avoid unwanted effects. Ethanol is an anaerobic metabolite that naturally accumulates in olive fruit during ripening. Gaseous ethanol is found to be released from the olive paste during malaxation (sealed conditions). Furthermore, under anoxicity, the ethanol release is roughly ten times higher in response to the absence of oxygen, that is, cell anaerobic respiration take place. Ethanol is an anaerobic metabolite that naturally accumulates in olive fruit during ripening. Gaseous ethanol is found to be released from the olive paste during malaxation (sealed conditions). Furthermore, under anoxicity, the ethanol release is roughly ten times higher in response to the absence of oxygen, that is, cell anaerobic respiration take place. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop aligned electrospun polyimide (PI) nanofibers (with rigid macromolecular backbone) reinforced PI (with flexible macromolecular backbone) nanocomposite films. Owing to uniform dispersion of aligned PI nanofibers and excellent interfacial adhesion/interaction between filler and matrix, the resulting nanocomposite films exhibited superior mechanical and thermal properties. The nanocomposite films were fabricated by co‐electrospinning of two polyamic acids (PAAs) including a rigid PAA of poly(p‐phenylene biphenyltetracarboximide) (BPDA‐PDA) and a flexible PAA of poly(1,4‐bis (3′,4′‐dicarboxyphenoxy) phenyldiphenyl ether tetramine) (HQDA‐ODA); upon thermal imidization, hybrid PAA nanofiber belts (with different weight ratios of BPDA‐PDA/HQDA‐ODA) were converted into hybrid PI nanofiber belts. Subsequently, these nanofiber belts were hot‐pressed to fabricate HQDA‐ODA PI nanocomposite films reinforced with BPDA‐PDA PI nanofibers; in specific, the nanocomposite film consisting of 80 wt % BP‐PI nanofibers exhibited the highest tensile strength and modulus of 957 ± 18 MPa and 12.32 ± 0.32 GPa, respectively. The nanocomposite films also possessed excellent thermal/thermomechanical properties. Therefore, these fiber‐reinforced PI nanocomposite films might be promising high‐performance structural/engineering materials that would be particularly useful for high‐temperature applications. Moreover, the strategy of co‐electrospinning hybrid nanofiber belts followed by hot‐pressing could provide an innovative approach for making high‐performance polymer‐matrix composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46849. [ABSTRACT FROM AUTHOR]

An oncogenic lncRNP complex controls E‐cadherin translation and highlights the importance of post‐transcriptional regulation in metastasis formation. [ABSTRACT FROM AUTHOR]

Plant development is exceptionally flexible as manifested by its potential for organogenesis and regeneration, which are processes involving rearrangements of tissue polarities. Fundamental questions concern how individual cells can polarize in a coordinated manner to integrate into the multicellular context. In canalization models, the signaling molecule auxin acts as a polarizing cue, and feedback on the intercellular auxin flow is key for synchronized polarity rearrangements. We provide a novel mechanistic framework for canalization, based on up-to-date experimental data and minimal, biologically plausible assumptions. Our model combines the intracellular auxin signaling for expression of PINFORMED (PIN) auxin transporters and the theoretical postulation of extracellular auxin signaling for modulation of PIN subcellular dynamics. Computer simulations faithfully and robustly recapitulated the experimentally observed patterns of tissue polarity and asymmetric auxin distribution during formation and regeneration of vascular systems and during the competitive regulation of shoot branching by apical dominance. Additionally, our model generated new predictions that could be experimentally validated, highlighting a mechanistically conceivable explanation for the PIN polarization and canalization of the auxin flow in plants. [ABSTRACT FROM AUTHOR]

The article lists the referees who have assisted the editors in this published journal of "Parasite Immunology" issue of 2007 which includes A. Ager, A. Bancroft and C. E. Lawrence.