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The determination of shear strength parameters for coarse granular materials such as rockfill and waste rocks is challenging due to their oversized particles and the minimum required ratio of 10 between the specimen width (W) and the maximum particle size (dmax) of tested samples for direct shear tests. To overcome this problem, a common practice is to prepare test samples by excluding the oversized particles. This method is called the scalping scaling down technique. Making further modifications on scalped samples to achieve a specific particle size distribution curve (PSDC) leads to other scaling down techniques. Until now, the parallel scaling down technique has been the most popular and most commonly applied, generally because it produces a PSDC parallel and similar to that of field material. Recently, a critical literature review performed by the authors revealed that the methodology used by previous researchers to validate or invalidate the scaling down techniques in estimating the shear strength of field materials is inappropriate. The validity of scaling down techniques remains unknown. In addition, the minimum required W/dmax ratio of 10, stipulated in ASTM D3080/D3080M-11 for direct shear tests, is not large enough to eliminate the specimen size effect (SSE). The authors' recent experimental study showed that a minimum W/dmax ratio of 60 is necessary to avoid any SSE in direct shear tests. In this study, a series of direct shear tests were performed on samples with different dmax values, prepared by applying scalping and parallel scaling down techniques. All tested specimens had a W/dmax ratio equal to or larger than 60. The test results of the scaled down samples with dmax values smaller than those of field samples were used to establish a predictive equation between the effective internal friction angle (hereafter named "friction angle") and dmax, which was then used to predict the friction angles of the field samples. Comparisons between the measured and predicted friction angles of field samples demonstrated that the equations based on scalping scaling down technique correctly predicted the friction angles of field samples, whereas the equations based on parallel scaling down technique failed to correctly predict the friction angles of field samples. The scalping down technique has been validated, whereas the parallel scaling down technique has been invalidated by the experimental results presented in this study. [ABSTRACT FROM AUTHOR]

Copyright of Comunicaçõe Geológicas is the property of Laboratorio Nacional de Energia e Geologia, I.P. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article informs that Conchological Club of Southern California (CCSC) maintained a list of record size shells from about 1950 to 1987, titled the List of Champions of the Lost Operculum Club (LOC). Topics include LOC records and World Size Records of Wagner and Abbott were incorporated into the new Registry of World Record Size Shells (WRS); and WRS passed a new rule allowed unphotographed listings to be replaced by smaller photographed specimens, with proper identification and measurement.

Botanical gardens are define by treasuring scientifically documented collections of plants of economic, scientific and educational interest. Since its foundation, the National Botanic Garden, belonging to the University of Havana, has developed its collections with emphasis on tropical plants, and in particular the flora of Cuba. As part of the above, the updated inventory of ferns grown at the National Botanic Garden is presented and the historical development of this specialized collection is analyzed. For this purpose, the taxa currently present were identified and quantified, and the year of incorporation, distribution status, conservation status, life form and illumination preferences were compiled for each one. Likewise, all of this was compiled for those taxa referenced at three earlier times in the collection (1993, 2000 and 2014), according to the institution’s Plant Records. From 1980 to the present, the fern collection of the National Botanic Garden has had 142 taxa, in 22 families and 55 genera. At present, 79 taxa, from 19 families and 37 genera, are in cultivation. The best represented families are Thelypteridaceae, Polypodiaceae and Dryopteridaceae. The analyzed collection has experienced fluctuations due to the loss and addition of taxa. Losses represent 44.8 % of the taxa that have made up the collection at some time, while more than half of the additions correspond to the 1980s. [ABSTRACT FROM AUTHOR]

Nonvascular plants (hornworts, mosses and liverworts) represent an important component of biodiversity in Cuban natural ecosystems; however, their presence in mountain agroecosystems has been little explored. The present study characterized the bryological diversity in agroforestry systems of the southern part of the Nipe and Cristal mountain ranges. The study area included six farms in the Santiago de Cuba province, in the municipalities of Mella (Pinalito and El Ocho de Mella) and Segundo Frente (El Guisaso, La Carolina, Las Mercedes and La Esperanza). In each one, random collections were made in the different habitats found. The bryological flora in the agroecosystems studied was represented by 37 species, in 30 genera and 21 families, with a predominance of generalist groups with a wide geographic distribution. The highest diversity was recorded in mosses (62 % of the total). No hornworts or endemics were recorded. The greatest diversity and exclusivity of taxa was recorded at the El Ocho de Mella farm. Among the forest formations evaluated, the mesophytic evergreen forest and the secondary vegetation registered the highest values of diversity. The 70 % of the taxa were collected as epiphytes and the corticolous taxa were the most representative group. The 62 % of the registered taxa presented a preliminary category of threat. Agroforestry systems, structured in areas of crops and areas of forests, represent an alternative to conserve remnants of the bryological flora in Cuban mountainous ecosystems. [ABSTRACT FROM AUTHOR]

The original description of the now extinct Australian Pig-footed Bandicoot Chaeropus ecaudatus Ogilby, 1838 was based on one specimen from which the tail was missing. Re-examination of the skull thought to be the holotype of C. ecaudatus, revealed that it was associated with a skeleton with caudal vertebrae, thereby negating its type status. The holotype has not been reliably sighted since 1860 and is presumed lost as it has not been identified in world collections. We designate PA422, a skull and partial skeleton in the Australian Museum, Sydney as neotype for Chaeropus ecaudatus. This arose from a recent taxonomic revision of Chaeropus that recognized two subspecies of C. ecaudatus, prompting resolution of the type material of nominate ecaudatus. [ABSTRACT FROM AUTHOR]

The article examines the natural specimen collecting journey of Alfred Russel Wallace in Dorey, New Guinea in the 19th century. Among his collections are insects, birds, and wooden carvings. Also cited are his book "The Malay Archipelago," and the display of Wallace's collections at museums like the Natural History Museum and Oxford University Museum of Natural History.

The axolotl (Ambystoma mexicanum) first became known in Europe through the work of Alexander von Humboldt. In 1804, he imported two specimens from an expedition to South America and displayed the animals in Paris. Wellknown scientists, such as August Weismann, carried out experiments on the metamorphosis in axolotls. Today, the axolotl is threatened in its natural habitat by anthropogenic disturbance. Large A. mexicanum-populations are maintained in laboratories around the world. The unique regenerative ability and other features are the reasons for the fact that this species is a model organism in many areas of research. Knowledge about organ regeneration in A. mexicanum is applied in the biomedical sciences and will help to solve open questions. [ABSTRACT FROM AUTHOR]

Four species of Pluteus Fr. are documented based on recently collected specimens from Alto Paraguay and Central Department, which correspond to the Pantanal and Humid Chaco ecoregions, respectively. Pluteus fibulatus Singer, P. longistriatus (Peck) Peck, P. petasatus (Fr.) Gillet, and P. triplocystis Singer are newly recorded species of the mycobiota of Paraguay; P. triplocystis is also a newly recorded for South America. Descriptions and photographs of both macro- and microscopic features of each species are included along with a brief discussion on their taxonomy, ecology, and distribution. [ABSTRACT FROM AUTHOR]

The Museu de Zoologia da Universidade de São Paulo (MZUSP), São Paulo, Brazil houses the largest and most representative Brazilian collection of Diptera. In the present study, following a recommendation of the International Code of Zoological Nomenclature, it is presented a catalogue of the type specimens of Diadocidiidae and Ditomyiidae (Diptera: Bibionomorpha) held in the collection of the MZUSP. Label data and the condition of preservation of 27 type specimens (nine holotypes, two paralectotypes, and 16 paratypes) of 14 Neotropical species are provided. [ABSTRACT FROM AUTHOR]

To better understand the molecular mechanisms underlying germ cell development in stony corals, this study focused on proliferating cell nuclear antigen (PCNA), which is an auxiliary protein of DNA polymerases and is principally responsible for DNA replication and repair. We performed the molecular identification and characterization of the complementary DNA for the pcna gene in the stony coral Euphyllia ancora. Quantitative reverse transcription-polymerase chain reaction analysis and Western blotting with anti-E. ancora PCNA antibody demonstrated that E. ancora PCNA gene products (transcripts and proteins) were present in all polyp tissues, including the testis and ovaries. Immunohistochemical analysis of spermatogenesis showed that intensive immunoreactivity of PCNA (irPCNA) was detected in the nuclei of spermatogonia. The irPCNA was also weakly detected in spermatocytes, and became almost undetectable in the spermatids and sperm. In contrast, in female germline cells, the irPCNA was detected in the nuclei of oogonia and all stage of oocytes. These results suggest that PCNA plays an important role in both the mitotic and meiotic processes of the coral germ cells. To the best of our knowledge, this study is the first to show the expression profile of the PCNA protein and its subcellular localization in coral germ-cell development. [ABSTRACT FROM AUTHOR]

The last 50 years have witnessed rapid changes in the ways that natural history specimens are collected, preserved, analyzed, and documented. Those changes have produced unprecedented access to specimens, images, and data as well as impressive research results in organismal biology. The stage is now set for a new generation of collecting, preserving, analyzing, and integrating biological samples—a generation devoted to interdisciplinary research into complex biological interactions and processes. Next-generation collections may be essential for breakthrough research on the spread of infectious diseases, feeding Earth's growing population, adapting to climate change, and other grand research challenges. A decade-long investment in research collection infrastructure will be needed. [ABSTRACT FROM AUTHOR]

The article offers information on the occurrence of snowflake-patched moray also known as Gymnothorax niphostigmus found in Vietnam. It discusses about the fish's geographical distribution range that occurs mostly in South China Sea ans also includes information of the validity of the species with the help of DNA barcoding and molecular phylogeny analysis.

Summary: Length–weight relationship (LWR) was estimated for 12 elasmobranch species; five shark species, four species of rays and three species of guitar fishes from north‐eastern Arabian Sea, India. Five major landing centres of Maharashtra were selected; Satpati (Lat. 19°43′15″N, Long. 72°42′00″E), Naigaon (Lat. 19°19′32″N, Long. 72°48′54″E), Versova (Lat. 19°08′33″N, Long. 72°48′11″E), New ferry Wharf (Lat. 18°57′29″N Long. 72°51′01″E) and Sassoon dock (Lat. 18°54′42″N, Long. 72°49′33″E). Samples were collected fortnightly during August 2016 to October 2017 from various gears; drift gill nets (Hung length 114–143 m and #100–270 mm) off Satpati coast at 35–50 m depth, dol nets (length 50–65 m and cod end # 30–69 mm) in Naigaon at 38–50 m depth and trawl (length 33–72 m and cod end # 17–32 mm) in Versova, New ferry Wharf and Sassoon dock operated at 20–50 m depth. Multiday fishing was carried out with 2–3 fishing trips in a month, each trip with duration of 7–13 days. Soaking time of gill net and dol net varied from 4 to 8 hr while each trawl haul lasted for 3–4 hr. Length–weight/Disc‐width‐weight relationship showed good fit with r2 values varying from 0.818 to 0.999. In addition to information on LWR, new maximum size for three species of elasmobranchs is reported in this paper. [ABSTRACT FROM AUTHOR]

Summary: The feeding habits of the Chinese minnow, Rhynchocypris oxycephalus (Sauvage & Dabry de Thiersant, 1874), were investigated in the Laohegou River, a tributary of the upper Yangtze River, China. A total of 412 specimens were collected by electrofishing in four seasons of 2012, 7 days per season. Diet composition was analyzed according to season, size classes and sex. The Chinese minnow is a generalist omnivorous species, whose diet consists of aquatic insects and plants. Besides algae, Hemiptera, Ephemerida, Trichoptera, Odonata, Diptera were the most dominat food items. The Shannon‐Wiener index on diet items showed no significant differences between major food items (p > .05) or between seasons, size classes and sexes. In contrast, fullness index and dietary breadth analysis both indicated significant diet changes between seasons. Consequently, this study provides information on feeding habits of R. oxycephalus, which may be useful in cultivation trials. [ABSTRACT FROM AUTHOR]

Summary: Present study evaluated the population status of the Bluemouth (Helicolenus dactylopterus) population distributed in the Antalya Bay for the first time, within the scope of two different surveys carried out in monthly basis, between September 2009 and June 2011 (200–900 m). In accordance with the major availability of the food, 80.9% of the total catch (in number) of the species at the upper slope (200–499 m). The 80.8% of all recruits’ specimens inhabits between 200 and 399 m while 72% of the total spawner specimens (TL ≥ 20 cm) inhabits at depths of between 600 and 799 m. Highest average abundance of the species was estimated 1,060 n/km2 (400 m), while the highest average biomass was 93 kg/km2 (600 m). Lengths of individuals ranged from 4 to 36 cm, and estimated ages from 0 to 27 years. Parameters of the von Bertalanffy growth curves were L∞ = 34.14 cm, K = 0.09 year−1, and t0 = −1.28 years. Margin band analysis confirmed the formation of a single growth annulus per year. In the central part of the otolith, close to the nucleus, a strongly marked check ring is formed which presenting first time for this species in the literature. The duration of the spawning stage for the females was observed between December and February. Selectivity rate of the commercially used 44 mm diamond codend mesh, with a 7.4 cm catch size, found to be very low for the species (a first spawning size of 17–20 cm). The stock of Bluemouth in the Antalya Bay was considered in above reference levels and in high abundance status due to estimated low fishing mortality (0.067−1), exploitation rate status below reference level (0.207−1) and Fcurr is very low than reference point (0.219−1). [ABSTRACT FROM AUTHOR]

The current study re-configured the HMPREF0351_11084 gene (GenBank accession number is NC_017960.1) to incorporate required sequence without impacting the protein structure. Which includes sties for a number of restriction enzymes, 6xHis-tag and stop codon at the end of gene. In addition to the gene optimization sequence through using bioinformatics software, then synthesized and sub-cloned into pGH cloning vector. The synthetic HMPREF0351_11084 gene was cloned into NcoI and EcoRI sites of pET28a expression vector under the control of T7 promoter. The recombinant pET28a expression vector (pET28a-HMPREF0351_11084) was transformed into BL21(DE3) cells. The right transformants of recombinant pET28a construct were verified using colony PCR, then the candidate plasmids (positive colonies) were further analyzed by plasmid PCR, restriction digestion and DNA sequencing. The results of these tests confirm the right construct of recombinant pET28a. To express recombinant target protein, the pET28a-HMPREF0351_11084/BL21 (DE3) cells were cultivated in Luria Bertani broth containing kanamycin antibiotic and induced with IPTG. The protein of expressing bacteria was analyzed by SDS-PAGE and stained with coomassie brilliant blue stain. The stained SDS-PAGE gel shows predicted target protein with molecular weight 24.9 kDa. This recombinant protein maybe serves as a new potential protein vaccine for pneumococcal. [ABSTRACT FROM AUTHOR]

This essay investigates the use of mounted natural history specimens as “natural illustrations” in Victorian books. These published collections of specimens, framed by literary and biblical extracts, differed from both scientific exsiccatae (published collections of dried specimens) and from albums compiled by private individuals in the nineteenth century. Advancing the tenets of natural theology, these volumes became implicated in charitable, consumerist, and political discourses. Though they resemble scientific specimens and the sea-side souvenirs of the Victorian period, natural illustrations, in their almost startling materiality, resist the logic of both the specimen and the souvenir. [ABSTRACT FROM AUTHOR]

The Middle and Upper Jurassic stage of evolution of the anaptychus-type ammonoid jaw apparatus is relatively poorly known due to a small number of findings and uncertainty of their taxonomic position. All previously found anaptychi of this age are preserved either in flattened and dissolved shells or separately from ammonoid conchs. Rhynchaptychus-type jaws were still hitherto unknown from Jurassic deposits. In this paper we describe three-dimensionally preserved ammonoid lower jaws from the Bajocian/Bathonian boundary (Middle Jurassic) beds of Dagestan, Russia. These findings demonstrate a wide variety of their shape and structure. One specimen, consisting only of organic matter which is considered as anaptychus sensu stricto , is located in situ in the body chamber of Lytoceras ( Dinolytoceras ) zhivagoi (Besnosov). Three specimens which likely belonged to any Phylloceratiadae ( Adabofoloceras , Holcophylloceras , or Pseudophylloceras which are presented in the ammonoid assemblage) contain prominent calcareous conchorhynchs, and the outer organic lamellae of these jaws were initially covered with a thin calcareous layer. The last lower jaw, probably from Nannolytocera s, has also a small calcareous conchorhynch in its tip despite a lack of coating. These findings are the first direct evidence of the existence of rhynchaptychus-type lower jaws in the Middle Jurassic. A variety in the shape and structure of the studied lower jaws indicates a variation in the mode of life and feeding behavior of Middle Jurassic ammonoids. [ABSTRACT FROM AUTHOR]

Ammonoids that lived in the wake of the end-Permian mass extinction are frequently encrusted by the shells of cementing bivalves, but the majority of these epizoans are too poorly preserved for a precise taxonomic identification. However, our huge collection of Griesbachian -- Dienerian (Early Triassic, c. 252-251 Ma) ammonoids from east Greenland, the Salt Range (Pakistan) and Spiti (India) includes three ammonoid specimens with epizoans that can reliably be identified as oysters, based on their attachment by the left valve and the morphology of their ligament area. Some of these oysters have their right (upper) valve preserved, which shows the characteristic morphology of Liostrea. These finds predate (1) the previously known first occurrence of oysters by c. 5Myr, (2) that of Gryphaeidae by c. 15Myr and (3) that of Liostrea by c. 20Myr. Moreover, the stratigraphic polarity indicates that Liostrea is a candidate ancestor of Gryphaea and not vice versa. The open-marine habitat of the Liostrea epizoans described herein provides an explanation for the unusual ecology of its putative descendent Gryphaea as a fully marine soft-bottom dweller with a preference for relatively deep water environments during the Triassic. The revised timing of the early phylogeny of oysters suggests that this bivalve clade underwent rapid morphological divergence during the initial phase of its evolution. [ABSTRACT FROM AUTHOR]

The identification of traits that influence the responses of the species to environmental variation provides a mechanistic perspective on the assembly processes of ecological communities. While much research linking functional ecology with assembly processes has been conducted with animals and plants, the development of predictive or even conceptual frameworks for fungal functional community ecology remains poorly explored. Particularly, little is known about the contribution of traits to the occurrences of fungal species under different environmental conditions., Wood-inhabiting fungi are known to strongly respond to habitat disturbance, and thus provide an interesting case study for investigating to what extent variation in occurrence patterns of fungi can be related to traits. We apply a trait-based joint species distribution model to a data set consisting of fruit-body occurrence data on 321 wood-inhabiting fungal species collected in 22 460 dead wood units from managed and natural forest sites., Our results show that environmental filtering plays a big role on shaping wood-inhabiting fungal communities, as different environments held different communities in terms of species and trait compositions. Most importantly, forest management selected against species with large and long-lived fruit-bodies as well as late decayers, and promoted the occurrences of species with small fruit-bodies and early decayers. A strong phylogenetic signal in the data suggested the existence of also some other functionally important traits than the ones we considered., We found that those species groups that were more prevalent in natural conditions had more associations to other species than species groups that were tolerant to or benefitted from forest management. Therefore, the changes that forest management causes on wood-inhabiting fungal communities influence ecosystem functioning through simplification of interactive associations among the fungal species., Synthesis. Our results show that functional traits are linked to the responses of wood-inhabiting fungi to variation in their environment, and thus environmental changes alter ecosystem functions via promoting or reducing species with different fruit-body types. However, further research is needed to identify other functional traits and to provide conclusive evidence for the adaptive nature of the links from traits to occurrence patterns found here. [ABSTRACT FROM AUTHOR]

Seven species of mesoplodont whales (genus Mesoplodon Gervais, 1850) named after the nineteenth century are based on valid descriptions. A checklist listing the original description and type material for each of these species is provided. Additional data given include type locality and illustrative sources, type material holding institution and type registration number. External morphology was recorded for all type specimens except Andrews' Beaked Whale ( Mesoplodon bowdoini) and the Pygmy Beaked Whale ( Mesoplodon peruvianus). [ABSTRACT FROM AUTHOR]

The deposits of the Carnian Kasımlar Formation within the Taurus Platform Units of south-western Turkey represent an important archive of a Late Triassic ecosystem. New palaeontological information was obtained by analysing the Kasimlarceltites mass occurrence, located within the Kasımlar Formation and named after the Lower Carnian (Julian) ammonoid genus Kasimlarceltites. This is the dominant taxon (> 94%) within the mass occurrence: nearly 775 million ammonoids and 50 million gastropods were extrapolated for the whole extension (at least 5 km2) of the Kasimlarceltites beds. This calculation is one of the main findings within this study, as it is the first time that such a fossil mass occurrence was quantified. Additionally, orientation measurements of the planispiral ammonoids and the helical gastropods enabled reconstructing the history of the mass occurrence and interpreting the underlying transport mechanisms. Further taphonomic aspects (e.g. biofabric, preservation, bioerosion or genetic classification) as well as comparisons with samples of the same acme zone from different localities near Aşağiyaylabel (AS IV, KA I-II) point to a two-phased genetic history. Accordingly, local mass mortality within the Kasimlarceltites fauna due to oxygen fluctuations or methane degassing may have initially led to a primary accumulation. These deposits were then reworked and redeposited basinward by gravity flows to create the present-day secondary allochthonous concentrations. [ABSTRACT FROM AUTHOR]

Siderastrea glynni Budd & Guzmán, 1994 was erroneously erected from live colonies of S. siderea (Ellis & Solander, 1768) unintentionally transferred from the Caribbean to the Pacific side of the Isthmus of Panamá. These corals had been used in experiments conducted in the early 1980s by KH Kleemann at Urabá Island, Taboga Islands, Gulf of Panamá, at the same site of the subsequent S. glynni discovery. Here, we offer evidence that live fragments deposited at Urabá Island in 1982 are the same found by Guzmán in 1992, and were inadvertently introduced from colonies of Caribbean S. siderea that were presumed to be dead. This morphological study builds on and supports recent genetic analyses of the S. glynni holobiont. In light of these findings, S. glynni should be regarded as a subjective junior synonym of S. siderea. [ABSTRACT FROM AUTHOR]

Ocean acidification is a major threat to calcifying marine organisms such as deep-sea cold-water corals (CWCs), but related knowledge is scarce. The aragonite saturation threshold (Ωa) for calcification, respiration and organic matter fluxes were investigated experimentally in the Mediterranean Madrepora oculata. Over 10 weeks, colonies were maintained under two feeding regimes (uptake of 36.75 and 7.46 µmol C polyp-1 week-1) and exposed in 2 week intervals to a consecutively changing air-CO2 mix (pCO2) of 400, 1600, 800, 2000 and 400 ppm. There was a significant effect of feeding on calcification at initial ambient pCO2, while with consecutive pCO2 treatments, feeding had no effect on calcification. Respiration was not significantly affected by feeding or pCO2 levels. Coral skeletons started to dissolve at an average Ωa threshold of 0.92, but recovered and started to calcify again at Ωa ≥1. The surplus energy required to counteract dissolution at elevated pCO2 (≥1600 µatm) was twice that at ambient pCO2. Yet, feeding had no mitigating effect at increasing pCO2 levels. This could be due to the fact that the energy required for calcification is a small fraction (1-3%) of the total metabolic energy demand and corals even under low food conditions might therefore still be able to allocate this small portion of energy to calcification. The response and resistance to ocean acidification are consequently not controlled by feeding in this species, but more likely by chemical reactions at the site of calcification and exchange processes between the calicoblastic layer and ambient seawater. [ABSTRACT FROM AUTHOR]

Zymoseptoria tritici (previously Mycosphaerella graminicola) causes Septoria tritici blotch (STB) on wheat. The population biology of Z. tritici has been exceptionally well characterized as a result of intensive studies conducted over nearly 30 years. These studies provided important insights into the biology, epidemiology and evolutionary history of Z. tritici that will prove useful for management of STB. The well-documented, rapid adaptation of Z. tritici populations to fungicide applications and deployment of wheat cultivars carrying both major gene and quantitative resistance reflects the high evolutionary potential predicted by the large effective population size, high degree of gene flow and high levels of recombination found in field populations of Z. tritici globally. QST studies that assessed the global diversity for several important quantitative traits confirmed the adaptive potential of field populations and laid the groundwork for quantitative trait loci (QTL) mapping studies. QTL mapping elucidated the genetic architecture of each trait and led to identification of candidate genes affecting fungicide resistance, thermal adaptation, virulence, and host specialization. The insights that emerged through these analyses of Z. tritici population biology can now be used to generate actionable disease management strategies aimed at sustainably reducing losses due to STB. The high evolutionary potential found in field populations of Z. tritici requires deployment of a corresponding dynamically diverse set of control measures that integrate cultural, chemical, biological and resistance breeding strategies. In this review, we describe and prioritize STB control strategies based on current knowledge of Z. tritici population biology and propose a future research agenda oriented toward long-term STB management. [ABSTRACT FROM AUTHOR]

A total of 6094 conodont specimens, assigned to 18 genera and 27 species, have been recovered from the uppermost Kuniutan and Miaopo formations, spanning the latest Darriwilian - early Sandbian in age, at the Jieling section, Yichang, Hubei Province. Three conodont zones have been recognized, i.e., in ascending order, the Pygodus serra Zone, the Pygodus anserinus - Yangtzeplacognathus jianyeensis Zone, and the Baltoniodus alobatus Zone. The conodont biodiversity in the Miaopo Formation shows a decreasing trend at Jieling. Multivariate statistical analysis of the conodont fauna from the Jieling section shows that the Baltoniodus and Periodon biofacies are present in the uppermost Kuniutan Formation, and the Periodon and Scabbardella biofacies can be recognized in the Miaopo Formation. [ABSTRACT FROM AUTHOR]

We analyzed both mitochondrial cox1 and plastid rbcL sequences from specimens of Pterocladiella from Madagascar and compared their morphologies with previously described species in the genus. Both molecular and morphological datasets demonstrated the presence of five species in Madagascar: P. australafricanensis, P. bartlettii, P. caerulescens, and two new species, P. feldmannii and P. hamelii, described here. Pterocladiella feldmannii is distinguished by plants with a size of about 6 cm with narrow axes and opposite to irregular branches, rhizines congested in medulla, tetrasporangial branchlets constricted at base of branches, tetrasporangial sori without sterile margins, and irregular arrangement of tetrasporangia. Pterocladiella hamelii is characterized by plants with a size of about 3 cm with flattened and thin erect axes and irregular branches, radial arrangement of subapical cells at tips of main axes, tetrasporangial sori with sterile margins and horizontal to irregular arrangement of tetrasporangia. Phylogenetic analyses based on cox1 and rbcL sequences revealed the sister relationship between P. feldmannii and P. hamelii, and their distant relationships to P. australafricanensis, P. bartlettii, and P. caerulescens. The Madagascan Pterocladiella is composed of two geographical elements: Madagascan endemic ( P. feldmannii and P. hamelii) and species with wide distributions ( P. australafricanensis, P. bartlettii and P. caerulescens). [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eight binomials of six recognized species of Indian Leucas R. Br. are lectotypified, namely, Leucas beddomei (Hook. f.) Sunojk. & P. Mathew, L. diffusa Benth., L. helianthemifolia Desf., L. nepetifolia Benth., L. pilosa Benth., L. pilosa Benth. var. pubescens Benth., L. ternifolia Desf. and L. vestita Benth. Two recognized taxa are neotypified, namely, L. angularis Benth. and L. lanata Benth. var. candida Haines. L. lanata Benth. var. candida Haines is raised to species rank as L. candida (Haines) R.Kr. Singh. L. pilosa Benth. is added to the flora of India. Additionally the following four recognized endemic species of Leucas of Myanmar are also lectotypified, Leucas collettii Prain, L. helferi Hook. f., L. ovata Benth. and L. teres Benth. [ABSTRACT FROM AUTHOR]

The paradigm that B cells are nonphagocytic was taken for granted for a long time until phagocytic B cells were found in early vertebrate animals. Thereafter, limited evidence has shown that human B cells may also internalize bacteria. However, whether human B cells can actively phagocytose bacteria has been less extensively investigated; in particular, the mechanisms and significance of the phagocytosis require clarification. Here, we show that the human Raji B cell line can phagocytose both live and dead Mycobacterium tuberculosis ( Mtb ), and the phagocytosed Mtb in turn affects the immune functions of the B cells. After incubation of Raji cells with Mtb , our confocal microscopy, electron microscopy and flow cytometry data showed that Raji cells effectively engulfed Mtb as well as latex beads. The phagocytic rate was proportional to the incubation time and the amount of Mtb or beads added. Additionally, we found that normal human serum could enhance the ability of Raji cells to phagocytose Mtb , while heat-inactivated serum reversed this promoting effect. The phagocytic process of B cells could partially be inhibited by cytochalasin B, an actin inhibitor. Importantly, the phagocytosed Mtb could regulate B cell immune functions, such as stimulating IgM production and upregulating the expression of the antigen-presenting costimulatory molecules CD80 and CD86. Therefore, our results provide the first evidence that human B cells can phagocytose Mtb in an active manner that is independent of bacterial viability, and phagocytosed Mtb can in turn regulate the immune activation of B cells. [ABSTRACT FROM AUTHOR]

Keys, full synonymy, descriptions, specimens examined, and illustrations are provided for the fern genus Polystichopsis. The genus occurs in the West Indies, with disjunct populations in Nicaragua and Isla Margarita, Venezuela. Seven species and one hybrid are recognized. The genus can be distinguished from other dryopteroid genera by the combination of creeping rhizomes, distichous leaves, lack of scales on the mature leaves, and straight, whitish multicellular hairs on the leaves. Although the genus has creeping rhizomes, it does not climb as do many other closely related dryopteroid genera. A new species, P. puberula, and new hybrid, P. × sanchezii (= P. chaerophylloides × P. pubescens), are described. Lectotypes are designated for Nephrodium pubescens var. breviculum , P. leucochaete, and P. muscosa. A list is provided of 28 names excluded from Polystichopsis, and another list is provided for accepted names and their synonyms that apply in the genus. [ABSTRACT FROM AUTHOR]

In the present work the presence of Paspalum notatum Flüggé (Poaceae) in Italy was reported for the first time. It is a neophyte native to America, known for applications in phytoremediation. Its typification, ecology and invasiveness status are also presented. [ABSTRACT FROM AUTHOR]

Summary: Length–weight relationships (LWRs) and length–length relationships (LLRs) of two endemic Channid fish species, Channa aurantimaculata Musikasinthorn, 2000 and C. stewartii (Playfair, 1867) were studied from Brahmaputra River basin in Assam, India. Sampling was done from May to December, 2017 and a total of 81 fish specimens were collected using bamboo traps. In the LWRs, b value for C. aurantimaculata and C. stewartii were 3.0456 and 2.9172 respectively. Maximum size recorded for C. aurantimaculata in the present study (34.1 cm) was higher than previous record in FishBase (19.1 cm). [ABSTRACT FROM AUTHOR]

Summary: Length‐weight relationships (LWRs) and length‐length relationships (LLRs) for three small indigenous fishes (Esomus danrica, Pachypterus atherinoides and Salmostoma bacaila) were reported from the Payra River, southern Bangladesh. Samples were collected using traditional fishing gear including cast net (mesh size ranges from 1.0 to 2.0 cm), seine net (mesh size ranges from 1.5 to 2.5 cm) and square lift net (mesh size ~ 1.0 cm) in August to September 2017. Allometric coefficient (b) values were 2.66 for E. danrica, 3.08 for P. atherinoides and 3.06 for S. bacaila. The LLRs were also highly significant with r2 ≥ .956. [ABSTRACT FROM AUTHOR]

Summary: This study reports the length‐weight relationships (LWRs) of Acrossocheilus beijiangensis Wu & Lin, 1977 and Barbodes semifasciolatus (Günther, 1868) from the upper reaches of Beijiang River, Guangdong Province, China. Sample sizes for the two fish species were 335 for A. beijiangensis and 106 for B. semifasciolatus. Fishes were collected on a monthly basis between November 2013 and December 2014 using gill nets (30 m long × 1.2 m high, mesh‐size 1.5 cm) and fish cages (mesh‐size 0.5 cm). LWRs were established as W = 0.0052L3.3249 (r2 = .9696) for A. beijiangensis and W = 0.0088L3.2405 (r2 = .9469) for B. semifasciolatus. No previous information is available on LWRs for these two species in FishBase. [ABSTRACT FROM AUTHOR]

Summary: This study provides length–weight relationships (LWRs) for three flatfish species: Cynoglossus bilineatus (Lacepède, 1802), Solea elongata (Day, 1877), and Pseudorhombus elevatus (Ogilby, 1912) from Motaf fishing grounds (latitude 27°00′ to 28°03′N; longitude 51°41′ to 52°11′E), Bushehr province, Iran. A total of 103 fish specimens were collected using shrimp trawler with 40 mm (stretched mesh size) at depths of 10–30 m between August and September 2017. The LWRs for fish species were W = 0.0019L3.353 for C. bilineatus: W = 0.0093L3.174 for S. elongata, and W = 0.006L3.181 for P. elevatus, respectively. [ABSTRACT FROM AUTHOR]