Usefulness and limitations of pollen characters in environmental studies based on Viola L. species (sect. Melanium Ging.)

The aim of these studies was to determine the effect of environmental pollution on pollen development. Pollen heteromorphism (the presence of pollen morphs differing in aperture number in one flower of a plant), pollen viability (stainability) and pollen grain size in European metallophytes from sect. Melanium Ging. (Viola L., Violaceae) were analyzed by SEM and histochemical staining.Plants’ tolerance to heavy metals is positively correlated with their pollen viability, which should be termed stainability as it depends on the staining method applied and is not correlated with pollen germination. Abortive pollen can be produced as an effect of heavy metals but also may result from hybridization, a very common phenomenon in pansies. Pollen stainability in hybrids can be high (even exceeding 70%) or low (barely above 20%), and stainable pollen grains can differ greatly in size (from very small to giant), indicating a cytological imbalance resulting from disturbed meiosis. The number of pollen apertures is an adaptive character in facultative metallophytes. Plants from a metallicolous population produced a wider range of aperture number (3, 4, 5) than plants from a non-metallicolous population, which developed only 4- and 5-aperturate pollen. Three-aperturate longer-lived pollen are favored in the harsh conditions of a metal-polluted environment

Embryogenesis in Sedum acre L.: structural and immunocytochemical aspects of suspensor development

The changes in the formation of both the actin and the microtubular cytoskeleton during the differentiation of the embryo-suspensor in Sedum acre were studied in comparison with the development of the embryo-proper. The presence and distribution of the cytoskeletal elements were examined ultrastructurally and with the light microscope using immunolabelling and rhodamine-phalloidin staining. At the globular stage of embryo development extensive array of actin filaments is present in the cytoplasm of basal cell, the microfilament bundles generally run parallel to the long axis of basal cell and pass in close to the nucleus. Microtubules form irregular bundles in the cytoplasm of the basal cell. A strongly fluorescent densely packed microtubules are present in the cytoplasmic layer adjacent to the wall separating the basal cell from the first layer of the chalazal suspensor cells. At the heart-stage of embryo development, in the basal cell, extremely dense arrays of actin materials are located near the micropylar and chalazal end of the cell. At this stage of basal cell formation, numerous actin filaments congregate around the nucleus. In the fully differentiated basal cell and micropylar haustorium, the tubulin cytoskeleton forms a dense prominent network composed of numerous cross-linked filaments. In the distal region of the basal cell, a distinct microtubular cytoskeleton with numerous microtubules is observed in the cytoplasmic layer adjacent to the wall, separating the basal cell from the first layer of the chalazal suspensor cells. The role of cytoskeleton during the development of the suspensor in S. acre is discussed

Non-invasive Monitoring of Intracranial Pressure Using Transcranial Doppler Ultrasonography: Is It Possible?

Although intracranial pressure (ICP) is essential to guide management of patients suffering from acute brain diseases, this signal is often neglected outside the neurocritical care environment. This is mainly attributed to the intrinsic risks of the available invasive techniques, which have prevented ICP monitoring in many conditions affecting the intracranial homeostasis, from mild traumatic brain injury to liver encephalopathy. In such scenario, methods for non-invasive monitoring of ICP (nICP) could improve clinical management of these conditions. A review of the literature was performed on PUBMED using the search keywords 'Transcranial Doppler non-invasive intracranial pressure.' Transcranial Doppler (TCD) is a technique primarily aimed at assessing the cerebrovascular dynamics through the cerebral blood flow velocity (FV). Its applicability for nICP assessment emerged from observation that some TCD-derived parameters change during increase of ICP, such as the shape of FV pulse waveform or pulsatility index. Methods were grouped as: based on TCD pulsatility index; aimed at non-invasive estimation of cerebral perfusion pressure and model-based methods. Published studies present with different accuracies, with prediction abilities (AUCs) for detection of ICP ≥20 mmHg ranging from 0.62 to 0.92. This discrepancy could result from inconsistent assessment measures and application in different conditions, from traumatic brain injury to hydrocephalus and stroke. Most of the reports stress a potential advantage of TCD as it provides the possibility to monitor changes of ICP in time. Overall accuracy for TCD-based methods ranges around ±12 mmHg, with a great potential of tracing dynamical changes of ICP in time, particularly those of vasogenic nature.Cambridge Commonwealth, European & International Trust Scholarship (University of Cambridge) provided financial support in the form of Scholarship funding for DC. Woolf Fisher Trust provided financial support in the form of Scholarship funding for JD. Gates Cambridge Trust provided financial support in the form of Scholarship funding for XL. CNPQ provided financial support in the form of Scholarship funding for BCTC (Research Project 203792/2014-9). NIHR Brain Injury Healthcare Technology Co-operative, Cambridge, UK provided financial support in the form of equipment funding for DC, BC and MC. The sponsors had no role in the design or conduct of this manuscript.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s12028-016-0258-

Systematic review of efficacies and adverse effects of treatments for Pityriasis lichenoides

Introduction: Pityriasis lichenoides (PL) is a papulosquamous dermatosis affecting both children and adults for which no standard treatment currently exists. The aims of our systematic review were to characterize different treatment options and develop an evidence-based treatment algorithm for PL. Methods: A systematic search of published literature on PL treatments was performed on December 23rd, 2017 via the Medline, Embase, CINAHL, CENTRAL, ClinicalTrials.gov, and the EU Clinical Trials Register databases. Results: Of 1090 abstracts retrieved, 27 full-text articles with 502 participants were included for analysis. 17 of the full-text articles were retrospective cohorts and 2 were randomized control studies. Treatment modalities included in these articles were phototherapy, antibiotics, methotrexate, pyrimethamine and trisulfapyrimidine, corticosteroids (CTS) and conservative treatment. Of these treatments, phototherapy led to complete remission in the highest proportion of patients and topical CTS was found to have been trialed in the highest number of patients. Conclusions: The current literature consists almost entirely of uncontrolled studies and none provide compelling data to support an evidence-based approach to PL treatment. PLC and PLEVA should be distinguished in response to treatment and definitions of response to treatment must be standardized. Additional randomized control studies with longer follow-ups will help better differentiate between treatment efficacies and adverse effects

Determinants of environmental management in the red sea hotels: Personal and organizational values and contextual variables

What motivates firms to adopt environmental management practices is one of the most significant aspects in the contemporary academic debate in which the review of the existing literature yields, with an obvious contextual bias toward developed world, contested theories and inconclusive findings. Providing a unique model that brings together the individual and organizational levels of analysis on firms' adoption of environmental management practices, this study aims to provide a new insight from the context of developing world. Data from 158 Red Sea hotels reveal two identifiable dimensions of environmental management-planning and organization, and operations-that can be explained as originating from different values. Whereas organizational altruism is a powerful predictor of both dimensions, managers' personal values and organizational competitive orientation are only relevant to environmental operations. The evidence also indicates that contextual variables such as chain affiliation, hotel star rating, and size are important to explain hotels' environmental management behaviors. © 2012 ICHRIE

Rab-dependent vesicular traffic affects female gametophyte development in Arabidopsis

Eukaryotic cells rely on the accuracy and efficiency of vesicular traffic. In plants, disturbances in vesicular trafficking are well studied in quickly dividing root meristem cells or polar growing root hairs and pollen tubes. The development of the female gametophyte, a unique haploid reproductive structure located in the ovule, has received far less attention in studies of vesicular transport. Key molecules providing the specificity of vesicle formation and its subsequent recognition and fusion with the acceptor membrane are Rab proteins. Rabs are anchored to membranes by covalently linked geranylgeranyl group(s) that are added by the Rab geranylgeranyl transferase (RGT) enzyme. Here we show that Arabidopsis plants carrying mutations in the gene encoding the beta subunit of RGT (rgtb1) exhibit severely disrupted female gametogenesis and this effect is of sporophytic origin. Mutations in rgtb1 lead to internalization of the PIN1 and PIN3 proteins from the basal membranes to vesicles in pro-vascular cells of the funiculus. Decreased transport of auxin out of the ovule is accompanied by auxin accumulation in a tissue surrounding the growing gametophyte. In addition, female gametophyte development arrests at the uni- or binuclear stage in a significant portion of the rgtb1 ovules. These observations suggest that communication between the sporophyte and the developing female gametophyte relies on Rab dependent vesicular traffic of the PIN1 and PIN3 transporters and auxin efflux out of the ovule.Joanna Rojek, Matthew R Tucker, Sara C Pinto, Michał Rychłowski, Małgorzata Lichocka, Hana Soukupova ... et al

Building a fault-tolerant quantum computer using concatenated cat codes

We present a comprehensive architectural analysis for a fault-tolerant quantum computer based on cat codes concatenated with outer quantum error-correcting codes. For the physical hardware, we propose a system of acoustic resonators coupled to superconducting circuits with a two-dimensional layout. Using estimated near-term physical parameters for electro-acoustic systems, we perform a detailed error analysis of measurements and gates, including CNOT and Toffoli gates. Having built a realistic noise model, we numerically simulate quantum error correction when the outer code is either a repetition code or a thin rectangular surface code. Our next step toward universal fault-tolerant quantum computation is a protocol for fault-tolerant Toffoli magic state preparation that significantly improves upon the fidelity of physical Toffoli gates at very low qubit cost. To achieve even lower overheads, we devise a new magic-state distillation protocol for Toffoli states. Combining these results together, we obtain realistic full-resource estimates of the physical error rates and overheads needed to run useful fault-tolerant quantum algorithms. We find that with around 1,000 superconducting circuit components, one could construct a fault-tolerant quantum computer that can run circuits which are intractable for classical supercomputers. Hardware with 32,000 superconducting circuit components, in turn, could simulate the Hubbard model in a regime beyond the reach of classical computing

Archival data on wild food plants used in Poland in 1948

<p>Abstract</p> <p>Background</p> <p>In 1948, Professor Józef Gajek initiated a detailed census of the wild edible plants used in Poland. The questionnaires were collected by correspondents of the Polish Folklore Society in 95 localities throughout Poland. A major part of these archival materials, including a substantial collection of herbarium specimens, had not undergone thorough analysis prior to this study, which presents a quantitative analysis of this archival set of data.</p> <p>Methods</p> <p>Herbarium specimens were identified and a database was created.</p> <p>Results</p> <p>Ninety-eight taxa identified to genus or species level, including 71 botanical species, identified using herbarium specimens, were found. On average only 11 edible plant species per locality were listed, the longest list included 39 species. No correlation between latitude and the number of edible species was found, whereas there was small but significant correlation with the longitude. Fruits were the most frequently collected part of plants. Most plants were primarily collected by women and children. Children both helped parents to collect wild fruits and also ate many species raw, which were not consumed by adults, but had often been eaten in the past. Eighteen of the taxa had not been reported in a recent comprehensive review of edible plants of Poland. <it>Stratiotes aloides</it>, used as a famine vegetable in the Łódź region, has never been reported as edible in any ethnobotanical literature.</p> <p>Conclusion</p> <p>The results undermine the conclusions of a recent comprehensive review of edible plants of Poland, which stated that many more wild edible plants have been collected in the Carpathians than in lowland Poland. However such results were shown to be caused by the substantially larger number of ethnographic studies undertaken in the Carpathians. In fact, large numbers of edible plant species were collected in the mid-20^thcentury in a few regions, particularly along the eastern border, in the Carpathians and in communities originating from the expanded Soviet Union, which had been resettled to the north-west of Poland in 1945.</p

New data about the suspensor of succulent angiosperms : ultrastructure and cytochemical study of the embryo-suspensor of Sempervivum arachnoideum L. and Jovibarba sobolifera (Sims) Opiz

The development of the suspensor in two species - Sempervivum arachnoideum and Jovibarba sobolifera - was investigated using cytochemical methods, light and electron microscopy. Cytological processes of differentiation in the embryo-suspensor were compared with the development of embryo-proper. The mature differentiated suspensor consists of a large basal cell and three to four chalazal cells. The basal cell produces haustorial branched invading ovular tissues. The walls of the haustorium and the micropylar part of the basal cell form the wall ingrowths typical for a transfer cells. The ingrowths also partially cover the lateral wall and the chalazal wall separating the basal cell from the other embryo cells. The dense cytoplasm filling the basal cell is rich in: numerous polysomes lying free or covering rough endoplasmic reticulum (RER), active dictyosomes, microtubules, bundles of microfilaments, microbodies, mitochondria, plastids and lipid droplets. Cytochemical tests (including proteins, insoluble polysaccharides and lipids are distributed in the suspensor during different stages of embryo development) showed the presence of high amounts of macromolecules in the suspensor cells, particularly during the globular and heart-shaped phases of embryo development. The protein bodies and lipid droplets are the main storage products in the cells of the embryo-proper. The results of Auramine 0 indicate that a cuticular material is present only on the surface walls of the embryo-proper, but is absent from the suspensor cell wall. The ultrastructural features and cytochemical tests indicate that in the two species - S. arachnoideum and J. sobolifera - the embryo-suspensor is mainly involved in the absorption and transport of metabolites from the ovular tissues to the developing embryo-proper