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Palynological features of tribe Astagaleae L. have been observed with scanning electron microscopy (SEM), to assess features that can be used to re‐examine the placement and taxonomic position of tribe. The palynomorph attributes of 10 species included in three genera of Astragaleae (Astragalus L., Glycyrrhiza L., and Oxytropis DC.) are investigated. The assignment of genus Oxytropis in tribe Astragaleae was also reevaluated based on pollen characters. Pollen appear to be prolate, prolate‐spheroidal, and subprolate. Polar axis size (P) varies from 31.3 μm ±1 to 17.5 μm ±1.4 and equatorial axis size (E) varies from 22.2 μm ±1.8 to 13.1 μm ±0.9. Prominent apertures found consistently dispersed along the surface of pollen. Three kinds of ornamentation pattern were recorded, that is, reticulate or reticulate‐perforate and perforate. The studied species display variation in equatorial and polar diameter, aperturation and sculpturing pattern, exine thickness, and pollen shape. On the basis of descriptive pollen features, a dichotomous taxonomic key and UPGMA analysis has been made for effortless and quick identification. The study concluded that disparities of the entire features are typically unrelenting and concerned with the species and shows potential systematic significance. The combination of palynological attributes in association with additional traits has prospective for systematic identification at species and genus level. [ABSTRACT FROM AUTHOR]

The calcareous Halimeda bioherms of the northern Great Barrier Reef, Australia are the largest actively accumulating Halimeda deposits worldwide. They contribute a substantial component of the Great Barrier Reef neritic carbonate factory, as well as the geomorphological development of Australia's northeast continental shelf. Halimeda bioherm geomorphology is complex, expressing three distinct variations in morphotype patterns: annulate, reticulate and undulate. Similar regular and irregular geomorphological patterning often results from scale‐dependent biophysical feedback mechanisms. Therefore, a better understanding of morphotype differentiation can inform the biotic and abiotic drivers of spatial heterogeneity in the bioherm ecosystem. Here, 3D LiDAR bathymetry is integrated with 2D sub‐bottom profile datasets to investigate surface topography and internal sedimentary architecture of Halimeda bioherms through space and time. Using the ESRI ArcGIS 3D Analyst and Benthic Terrain Modeller extensions, the bioherm surface and subsurface geomorphometric characteristics were quantified for the annulate, reticulate and undulate morphotypes. Significant variation was found between the three bioherm morphotypes in their surface topography, internal structure, volume, slope gradients and terrain complexity. Therefore, their geomorphology is probably influenced by differing processes and biophysical feedback mechanisms. The complex surface topography does not appear to be inherited from the antecedent substrate, and preferred aspect orientations resulting from hydrodynamic forcing appear to be limited. It is suggested here that autogenic dynamics or biotic self‐organization similar to patterns and processes in other marine organo‐sedimentary systems modulates Halimeda bioherm geomorphology, and some hypotheses are offered towards future studies. Morphotype differentiation has implications for the development of the Halimeda bioherm carbonate factory, rates of sediment aggradation and progradation, and variable capacity to fill accommodation space. Self‐organization dynamics and morphology differentiation in Modern bioherm systems could potentially inform palaeo‐environmental interpretations of fossil bioherms and phylloid algal mounds on geological timescales. [ABSTRACT FROM AUTHOR]

Octoblepharum peristomiruptum, a new species of moss in the family Octoblepharaceae from Panama and Brazil, is described and illustrated. The new species is characterised by plants with a reddish-purple colour particularly at the leaf bases, peristomes of eight teeth, each tooth composed of two rows of cells, fenestrate and usually completely separated at the base, strongly vertically striate-reticulate, some striations forked-like in shape. At the base of the teeth, some striations are horizontally orientated, poorly developed or absent, particularly on the cell wall that is rupturing in the separation of the vertical rows of the cells that form each tooth. [ABSTRACT FROM AUTHOR]

Dowling-Degos Disease is a rare, pigmentary disorder with variable presentations. The most common among them are hyperpigmented macules and reticulate pigmentary anomaly of flexures. Many other phenotypic variations of Dowling-Degos disease have been reported in literature. We present here a case of Dowling-Degos disease with comedo-like lesions and pits without typical flexural hyperpigmented macules. [ABSTRACT FROM AUTHOR]

Dowling–Degos disease (DDD) is a rare autosomal dominant genodermatosis characterized by reticulate brown-to-black pigmentation of the flexures, pitted perioral acneiform scars, and comedo-like follicular papules on the flexures. The diagnosis is based on characteristic clinical and histopathological features. DDD has been found to occur in association with hidradenitis suppurativa (HS), arthritis, epidermoid cysts, keratoacanthomas, and squamous cell carcinoma. To date, there is only one report of DDD associated with HS and polyarticular arthritis. [ABSTRACT FROM AUTHOR]

Halimeda bioherms occur as extensive geological structures on the northern Great Barrier Reef (GBR), Australia. We present the most complete, high-resolution spatial mapping of the northern GBR Halimeda bioherms, based on new airborne lidar and multibeam echosounder bathymetry data. Our analysis reveals that bioherm morphology does not conform to the previous model of parallel ridges and troughs, but is far more complex than previously thought. We define and describe three morphological sub-types: reticulate, annulate, and undulate, which are distributed in a cross-shelf pattern of reduced complexity from east to west. The northern GBR bioherms cover an area of 6095 km, three times larger than the original estimate, exceeding the area and volume of calcium carbonate in the adjacent modern shelf-edge barrier reefs. We have mapped a 1740 km bioherm complex north of Raine Island in the Cape York region not previously recorded, extending the northern limit by more than 1° of latitude. Bioherm formation and distribution are controlled by a complex interaction of outer-shelf geometry, regional and local currents, coupled with the morphology and depth of continental slope submarine canyons determining the delivery of cool, nutrient-rich water upwelling through inter-reef passages. Distribution and mapping of Halimeda bioherms in relation to Great Barrier Reef Marine Park Authority bioregion classifications and management zones are inconsistent and currently poorly defined due to a lack of high-resolution data not available until now. These new estimates of bioherm spatial distribution and morphology have implications for understanding the role these geological features play as structurally complex and productive inter-reef habitats, and as calcium carbonate sinks which record a complete history of the Holocene post-glacial marine transgression in the northern GBR. [ABSTRACT FROM AUTHOR]

Confluent and reticulated papillomatosis (CRP) of Gougerot and Carteaud was first typified in 1927. With the help of electron microscopy, it has been elucidated that CRP arises due to aberrant keratinization. However, till date, there is no clear consensus on the etiologic trigger for CRP. Prevailing postulates include a bacterial trigger by Dietzia papillomatosis (type strain N 1280T), an exaggerated cutaneous response to Malassezia furfur, an endocrine basis stemming from insulin resistance, ultraviolet light-induced epidermal change, amyloid deposition, and a loss-of-function mutation in keratin 16. CRP typically presents as asymptomatic hyperpigmented papules and plaques with peripheral reticulation over the nape, axillae, upper chest, and upper back, occasionally with extension superior to the forehead and inferior to the pubic region. Dermoscopy may be used in the evaluation of CRP, but its diagnosis is made on clinical grounds given its nonspecific histopathological findings. Although successful treatment with topical keratolytics, retinoids, or antifungals has been reported, antibiotics, such as minocycline, at anti-inflammatory doses have emerged as a preferred therapeutic option. In this article, we review the diagnostic considerations in CRP and its therapeutic options. [ABSTRACT FROM AUTHOR]

The leaf venation of angiosperms is key to their terrestirial dominance. These higher land plants include maple, corn, and ISS model organism Arabidopsis thaliana. The venation-dependent photosynthetic capacity of angiosperm leaves is largely responsible for terrestrial production of glucose and atmospheric oxygen, and may be fundamentally important to long-term space colonization. Leaf studies in orbit, where human-tended experiments are limited, can be enhanced by quantifying complex venation patterning. VESsel GENeration Analysis (VESGEN), a beta-level NASA software that analyzes vertebrate and human vascular branching for biomedical applications, is therefore being modified to map the branching venation patterns of dicot angiosperm leaves. By physiological branching rules, VESGEN decomposes a continuously connected vascular tree into its structural (dendritic) branching and reticulate (networked) capillary components. For an arabidopsis juvenile leaf flown on NASA Space Shuttle Mission (STS)-130, the venation patterning of larger structural vessel orders 1°-2° remained relatively constant compared to normal gravity (by vessel number density Nv, 1.24E-5/micron², and 1.29E- 5/micron², respectively). However, as a measure of increased venation maturity, Nv of smaller reticulate orders ≥ 3° increased considerably from 7.7E-6/micron² in ground control to 1.74E- 5/micron² in the STS-130 leaf. Vascular geometric complexity is another feature of plant development that is governed in part by changes in gene expression patterns responding to environmental influence. We therefore propose that the mapping of leaf venation patterns by VESGEN can provide additional insight into plant responses to the spaceflight environment. [ABSTRACT FROM AUTHOR]

Background Phylogenetic networks are employed to visualize evolutionary relationships among a group of nucleotide sequences, genes or species when reticulate events like hybridization, recombination, reassortant and horizontal gene transfer are believed to be involved. In comparison to traditional distance-based methods, quartet-based methods consider more information in the reconstruction process and thus have the potential to be more accurate. Results We introduce QuartetSuite, which includes a set of new quartet-based methods, namely QuartetS, QuartetA, and QuartetM, to reconstruct phylogenetic networks from nucleotide sequences. We tested their performances and compared them with other popular methods on two simulated nucleotide sequence data sets: one generated from a tree topology and the other from a complicated evolutionary history containing three reticulate events. We further validated these methods to two real data sets: a bacterial data set consisting of seven concatenated genes of 36 bacterial species and an influenza data set related to recently emerging H7N9 low pathogenic avian influenza viruses in China. Conclusion QuartetS, QuartetA, and QuartetM have the potential to accurately reconstruct evolutionary scenarios from simple branching trees to complicated networks containing many reticulate events. These methods could provide insights into the understanding of complicated biological evolutionary processes such as bacterial taxonomy and reassortant of influenza viruses. [ABSTRACT FROM AUTHOR]

Analysis of reticulate leaf mutants supports the significance of plastid retrograde signaling in cell development and highlights the significance of the bundle sheath in C3 photosynthesis for supplying the mesophyll with metabolites during leaf development.The development of a plant leaf is a meticulously orchestrated sequence of events producing a complex organ comprising diverse cell types. The reticulate class of leaf variegation mutants displays contrasting pigmentation between veins and interveinal regions due to specific aberrations in the development of mesophyll cells. Thus, the reticulate mutants offer a potent tool to investigate cell-type-specific developmental processes. The discovery that most mutants are affected in plastid-localized, metabolic pathways that are strongly expressed in vasculature-associated tissues implicates a crucial role for the bundle sheath and their chloroplasts in proper development of the mesophyll cells. Here, we review the reticulate mutants and their phenotypic characteristics, with a focus on those in Arabidopsis thaliana. Two alternative models have been put forward to explain the relationship between plastid metabolism and mesophyll cell development, which we call here the supply and the signaling hypotheses. We critically assess these proposed models and discuss their implications for leaf development and bundle sheath function in C3 species. The characterization of the reticulate mutants supports the significance of plastid retrograde signaling in cell development and highlights the significance of the bundle sheath in C3 photosynthesis. [ABSTRACT FROM AUTHOR]

The term "reticulate" is used for clinical description of skin lesions that are configured in a net?like pattern. Many primary and secondary dermatoses present in such patterns involving specific body sites. Certain cutaneous manifestations of systemic diseases or genodermatoses also present in such manner. This review classifies and describes such conditions with reticulate lesions and briefly, their associated features. [ABSTRACT FROM AUTHOR]

A study of the spores of 64 neotropical and palaeotropical taxa of the genus Blechnum was performed using scanning electron microscopy (SEM). Two basic types of perispores were recognised: perispore smooth or only slightly ornamented (laevigate, with micro-granules or micro-lamellae, venulose and rugulate), and perispore ornamented (rugate, low reticulate, cristate-reticulate, orbiculate, and colliculate). SEM observations allow for distinguishing differences in the structure of perispores, but the character does not correlate with the ornamentation. The smooth exospore predominates among the studied species. Results suggest that perispore characters have important diagnostic value, since different combinations of ornamentation/structure were found among the studied species. Moreover, when spore characters are considered together with other morphological traits of the sporophytes and the habit of plants, ornamentation of spores becomes a useful complementary feature at the specific level. The results are discussed in light of the recent systematic studies and emphasise that any eventual subdivision of the genus Blechnum must include characters of the sporophyte as well as spore features to ensure a more robust classification than the previously proposed. The spores also show a significant affinity between Blechnum and other genera of Blechnaceae, which was also suggested by recent phylogenetic studies. [ABSTRACT FROM AUTHOR]