178,595 research outputs found
Stictodiscus manilensis D. M. Williams, P. A. Sims, & J. Witkowski 2021, sp. nov.
No full text<i>Stictodiscus manilensis</i> D.M.Williams, P.A.Sims, & J.Witkowski, <i>sp. nov.</i> <p> <b>Type:—</b> Philippines: Manila (‘ Manilla’), (holotype BM Adams F 1148 = Fig. 1, one specimen); BM 5473 (Deby, one specimen), BM 7431 (Deby, one specimen), BM 8865 (Deby, ‘ Manilla’ = Fig. 3, one specimen), BM 10652 (Deby, L.H. 826, two specimens), BM 45641 (Sturt, A578, three specimens), BM 45863 (Sturt A800, one specimen). Singapore: BM 10435 (Deby, L.H. 547, one specimen).</p> <p>Valves circular with flat valve face; mantle distinctive. Valve with small central annulus, radiating network of ‘siliceous bars’ leading to areolae, mostly biseriate. Raised siliceous thickenings surround series of radiating inner areolae, becoming more conspicuous towards valve mantle. No other surface structures.</p>Published as part of <i>Williams, David M., Sims, Pat A. & Witkowski, Jakub, 2021, Notes on the diatom collection of the Natural History Museum, London (BM) V: (a) ' Stictodiscus manillensis' nom. nud., (b) Stictodiscus pantocsekii and ' Stictodiscus pantocsekii var. minor', (c) a note on the name ' Stictodiscella'; and (d) some comments on Jósef Pantocsek's Beiträge zur Kenntnis der Fossilen Bacillarien, pp. 167-174 in Phytotaxa 507 (2)</i> on page 169, DOI: 10.11646/phytotaxa.507.2.4, <a href="http://zenodo.org/record/5425611">http://zenodo.org/record/5425611</a>
A Reconfigurable SOM Hardware Accelerator
No full textPorrmann M, Franzmeier M, Kalte H, Witkowski U, Rückert U. A Reconfigurable SOM Hardware Accelerator.A dynamically reconfigurable hardware accelerator for self-organizing
feature maps is presented. The system is based on the universal rapid prototyping system RAPTOR2000 that has been developed by the authors. The modular prototyping system is based on XILINX FPGAs and is capable of emulating hardware implementations with a complexity of more than 24 million system
gates. RAPTOR2000 is linked to its host – a standard personal computer or
workstation – via the PCI bus. For the simulation of self-organizing maps a module has been designed for the RAPTOR2000 system, that embodies an FPGA of the Xilinx Virtex series and optionally up to 128 MBytes of SDRAM. A speedup of about 50 is achieved with five FPGA modules on the RAPTOR2000 system compared to a software implementation on a state of the art personal computer for typical applications of self-organizing maps
Gliwiczia skvortzowii Kulikovskiy, Lange-Bertalot & Witkowski 2013, sp. nov.
No full text<i>Gliwiczia skvortzowii</i> Kulikovskiy, Lange-Bertalot & Witkowski <i>sp. nov.</i> Figs. 1–42 <p>Frustules with a horse shoe-like internal cavum at both raphe and rapheless valve as characteristic of the genus. Valves broadly elliptical with broadly to weakly cuneately rounded ends. Length 12–24 µm, breadth 8–13 µm.</p> <p>LM, raphe valve (Figs 20–32): Raphe filiform, straight, external central ends slightly expanded, distal ends shortly indistinctly deflected. Axial area narrow, linear, proximally broadening into a deltoid shape. Central area rhombi at the central nodule forming ca. 1.5 µm broad stauros to the valve margin unilaterally; on the opposite side the stauros appears interrupted by the elliptical cavum, at the margin (but see SEM, external view Figs 33, 34). Striae 24–25 in 10 µm, radiate throughout with several intercalated short ones at the margins proximally. Areolae punctate, ca. 30 in 10 µm.</p> <p>LM, rapheless valve (Figs 1–19): Axial and proximal central area rhombic-lanceolate; central area forming a stauros unilaterally which appears obscured on the opposite side by an elliptical cavum. Striae ca. 24 in 10 µm, becoming progressively radiate from proximal towards distal part of the valve; no shorter striae intercalated at margins. Areolae irregularly spaced, considerably coarser than in raphe valves, 15–18 in 10 µm. SEM, raphe valve, external view (Figs 33–36): Raphe with small external central pores and distal ends more or less distinctly to opposite sides deflected. Distal ends may be pore-like expanded at a junction between the valve face and the mantle. The stauroid central area appears clearly asymmetrical becoming expanded towards the margin at that side where the cavum lies internally. Areola foramina are circular and open.</p> <p>SEM, raphe valve, internal view (Figs 37–40): Central raphe ends deflected clearly to opposite sides as generally characteristic for achnanthoid and cocconeoid monoraphid genera. The stauros together with the raphe sternum is strongly elevated above the internal valve surface. The conspicuous cavity is opened by a relatively small aperture. Areolae uniseriate, small, approximately circular. Occlusion membranes visible or destroyed.</p> <p>SEM, rapheless valve, internal view (Figs 41–42): The relief-like appearance of the rhombical sternum, stauros and cavum generally as in the raphe valve. Areola pattern differs from raphe valves by larger apertures lying in crater-like depressions, becoming smaller and transapically elongated at valve mantles. Occlusion membranes have become corroded more or less strongly.</p> <p>Type: slide no. 15645m (holotypus here designated see Fig. 2) in collection Maxim Kulikovskiy, I.D. Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences (IBIW) 20.07.1965, leg. A.P. Skabitschewsky.</p> <p>Isotype: slide no. 15645a in collection Andrzej Witkowski, Institute of Marine Sciences, University of Szczecin (SZCZ).</p> <p>Distribution: As yet known only from the Lake Baikal.</p> <p>Etymology: This species dedicated to Boris Skvortzow one of the pioneers of the diatomological studies in Lake Baikal.</p>Published as part of <i>Kulikovskiy, Maxim, Lange-Bertalot, Horst & Witkowski, Andrzej, 2013, Gliwiczia gen. nov. a new monoraphid diatom genus from Lake Baikal with a description of four species new for science, pp. 1-16 in Phytotaxa 109 (1)</i> on pages 3-5, DOI: 10.11646/phytotaxa.109.1.1, <a href="http://zenodo.org/record/5078671">http://zenodo.org/record/5078671</a>
Cymatosirella taylorii Dabek & Witkowski 2013, sp. nov.
No full text<i>Cymatosirella taylorii</i> Dąbek & Witkowski <i>sp. nov.</i> (Figs 44–51 [LM], Figs 52–58 [SEM]) <p>Frustules rectangular in girdle view with undulated outline. Valves lanceolate to elliptical, 4–13 µm long and 1–4 µm wide. Central part of valve face and apices elevated. Valve surface areolated, with ca. 50 areolae in 10 µm. Areolae distributed over the whole valve face.</p> <p> <b>Type:</b> — SOUTH AFRICA. Western Cape Province: eastern part of Langebaan Lagoon, Saldanha Bay, sandy sediment from the intertidal sandbank (33°6’788’’S; 18°2’631’’E) collected on 19 th February 2011 by Dąbek, Witkowski & Archibald (SZCZ 17582, holotype!).</p> <p> <b>Habitat:</b> —The eastern part of Langebaan Lagoon is a shallow, sandy tidal pool. High and low tide occur twice a day. Sea surface water temperature exceeds 18° C</p> <p> <b>Etymology:</b> —Named after and dedicated to our friend and prominent South African diatomologist Dr. Jonathan Taylor (North-West University, Potchefstroom, South Africa).</p> <p> <b>Observations:</b> —The frustules are rectangular in girdle view with an undulated outline (Figs 44–47, 52). Cells are predominantly solitary, but occasionally two cells were found joined together (Fig. 44). The girdle is broad, and composed of numerous bands bearing one row of fine puncta (Fig. 52). The valves are lanceolate to elliptical, 4–13 µm long and 1–4 µm wide (Figs 48–51, 53). The central part of the valve face and apices are elevated (Figs 54, 56). The valve surface is strongly ornamented with areolae, ca. 50 in 10 µm (Figs 53–56). Near the central elevation, areolae are randomly distributed; further towards the apices they are arranged in longitudinal rows (Figs 53, 55, 56). Occlusions have not been observed. Each valve bears two ocelluli, composed of 7–10 porelli, with 1–2 central ones (Figs 57, 58). The ocelluli are surrounded by a hyaline ring of silica (Figs 53, 55, 57). No areolae occur near the ocelluli (Figs 53, 57). Spines were observed only rarely. Processes, pili, fascia nor pseudosepta have not been observed.</p> <p> <b>Ecology and geography:</b> — <i>Cymatosirella taylorii</i> has been found in only one sandy sample (SZCZ 17582, the holotype) from an intertidal sandbank in the eastern part of the Langebaan Lagoon. Only a dozen valves have been found. This species most probably belongs to the epipsammon.</p>Published as part of <i>Dąbek, Przemysław, Sabbe, Koen, Witkowski, Andrzej, Archibald, Colin, Kurzydłowski, Krzyszof J. & Zgłobicka, Izabela, 2013, Cymatosirella Dąbek, Witkowski & Sabbe gen. nov., a new marine benthic diatom genus (Bacillariophyta) belonging to the family Cymatosiraceae, pp. 42-56 in Phytotaxa 121 (1)</i> on page 50, DOI: 10.11646/phytotaxa.121.1.2, <a href="http://zenodo.org/record/5079466">http://zenodo.org/record/5079466</a>
Cymatoneis margarita Witkowski
No full text<p> <b> 46. <i>Cymatoneis margarita</i> Witkowski (Fig. 105)</b> </p> <p> <b>Type locality:</b> Orum Beach, Oman.</p> <p> <b>References:</b> Witkowski <i>et al.</i> 2000. p. 179, pl. 109, figs 9–17.</p> <p> <b>Morphometrics:</b> Valves 16–17 (13.5–18) μm long, 6–6.3 (5–6) μm wide, and transapical striae 18–19 (18–20) in 10 μm.</p> <p> <b>Remarks:</b> This species differs from other <i>Cymatoneis</i> in smaller size and lanceolate to elliptic-lanceolate valve outline (Witkowski <i>et al.</i> 2000). <i>Cymatoneis margarita</i> is distributed in Oman as type locality, the Mississippi Delta and Borneo (Witkowski <i>et al.</i> 2000). Since then, it has been reported off the coasts of Guinea, West Africa (Compère and Riaux-Gobin 2009). Although the species have been reported in a few areas, it seems to be pantropical taxon in warmer ocean.</p> <p>This taxon has been found a few times in sand beaches of the Seogwipo coast, representing a new report to South Korea.</p>Published as part of <i>Joh, Gyeongje, 2021, Distribution and frequent occurrence of diatom taxa (Bacillariophyta) inhabiting warmer oceans in Seogwipo coast of Jeju Island, southernmost Korea, pp. 1-67 in Phytotaxa 517 (1)</i> on page 33, DOI: 10.11646/phytotaxa.517.1.1, <a href="http://zenodo.org/record/8061058">http://zenodo.org/record/8061058</a>
Gliwiczia tenuis Kulikovskiy, Lange-Bertalot & Witkowski 2013, sp. nov.
No full textGliwiczia tenuis Kulikovskiy, Lange-Bertalot & Witkowski sp. nov. Figs 43–66 Frustules with a horse shoe-like internal cavum at both raphid and rapheless valve as characteristic of the genus. Valves broadly elliptical with broadly rounded ends. Length 7–13 µm, breadth 4.6–8 µm. LM, raphe valve (Figs 56–58): Raphe filiform, straight central ends slightly expanded, distal ends indistinct. Axial area narrow, linear. Central area forming a narrow, ca. 0.5 µ m broad stauros at both sides but unilaterally obscured by the elliptical cavum. Striae radiate throughout, becoming progressively stronger radiate to the ends, 28–33 in 10 µm. Areolae not discernible. LM, rapheless valve (Figs 43–55): Axial and central area merging into a wide elliptical space, striae therefore restricted to a marginal zone. No stauros interrupts the striae opposite to the side with the cavum. Striae 21–24 in 10 µm. Areolae not discernible. SEM, raphless valve, internal view (Figs 59–64): Sternum with raphe vestiges visible as a shallow elevation above the central axial area. The cavum is comparatively short, restricted to the marginal zone. A stauros is barely or indistinctly developed. A gap between the striae opposite to the cavum is lacking regularly. Areolae 50–60 in 10 µm. SEM, raphe valve, internal view (Fig. 65): Central raphe ends deflected clearly to opposite sides. The stauros together with the raphe sternum is strongly elevated above the internal valve surface. Cavum present extended from the centre nodule to the valve margin. Areolae uniseriate, small, approximately circular. SEM, raphe valve, external view (Fig. 66): Raphe with small central pores and more or less distinctly to opposite sides deflected distal ends that may be pore-like expanded at junction between valve face and mantle. The central area in a form of stauros appears clearly asymmetrical becoming expanded towards the margin at that side where the cavum occurs internally. Areola foramina are circular and open. Type: slide no. 15645m (holotypus here designated see Fig. 46) in collection Maxim Kulikovskiy, I.D. Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences (IBIW) 20.07.1965, leg. A.P. Skabitschewsky. Isotype: slide no. 15645a in collection Andrzej Witkowski, Institute of Marine Sciences, University of Szczecin (SZCZ). Distribution: As yet known from the Lake Baikal. Etymology: tenuis in Latin means smaller one.Published as part of Kulikovskiy, Maxim, Lange-Bertalot, Horst & Witkowski, Andrzej, 2013, Gliwiczia gen. nov. a new monoraphid diatom genus from Lake Baikal with a description of four species new for science, pp. 1-16 in Phytotaxa 109 (1) on pages 6-8, DOI: 10.11646/phytotaxa.109.1.1, http://zenodo.org/record/507867
Gliwiczia latarea Kulikovskiy, Lange-Bertalot & Witkowski 2013, sp. nov.
No full textGliwiczia latarea Kulikovskiy, Lange-Bertalot & Witkowski sp. nov. Figs 67–88 Frustules with a horse shoe-like internal cavum at both raphid and rapheless valve as characteristic of the genus. Valves broadly elliptical with broadly rounded ends. Length 11–15 µm, breadth 6.5–9.5 µm. LM, raphe valve (Figs 79–83): Raphe filiform, straight, central ends slightly expanded, distal ends hardly noticeably deflected to opposite sides. Axial area narrow, linear, barely widened proximally. Central area forming a narrow, ca. 1 µm broad stauros at both sides but unilaterally masked towards margins by the elliptical cavum. Striae radiate throughout but becoming progressively stronger radiate to the ends 27-33 in 10 µm. Areolae difficult to discern, more than 30 in 10 µm. LM, rapheless valve (Figs 67–78): Axial and central area merging to a wide elliptical space, striae therefore restricted to a marginal zone. Nevertheless on the side opposite to the cavum a short stauros is clearly marked. Striae 21–24 in 10 µm. SEM, raphe valve, internal view (Fig. 84): Central raphe ends deflected clearly to opposite sides. The stauros together with the raphe sternum is elevated above the internal valve surface. Cavum in circle shape present extended on the one side of the sternum. Areolae uniseriate, small, approximately circular or elongated. SEM, rapheless valve, internal view (Figs 85–88): The internal nonperforated area is not simply flat but a narrow sternum and similarly to the stauros relief-like elevated. Vestiges of a raphe are present. The cavum appears prominently extended ca. 1/4 of the valve width. Areolae, ca. 40 in 10 µ m, are occluded by membranes. Type: slide no. 15645m (holotypus here designated see Fig. 68) in collection Maxim Kulikovskiy, I.D. Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences (IBIW) 20.07.1965, leg. A.P. Skabitschewsky. Isotype: slide no. 15645a in collection Andrzej Witkowski, Institute of Marine Sciences, University of Szczecin (SZCZ). Distribution: only found in Lake Baikal associated with the other three taxa described here as new. Etymology: latarea in Latin means possessing a broad areaPublished as part of Kulikovskiy, Maxim, Lange-Bertalot, Horst & Witkowski, Andrzej, 2013, Gliwiczia gen. nov. a new monoraphid diatom genus from Lake Baikal with a description of four species new for science, pp. 1-16 in Phytotaxa 109 (1) on pages 8-10, DOI: 10.11646/phytotaxa.109.1.1, http://zenodo.org/record/507867
Case Report: melanoma and melanocytic nevus differentiation with reflectance confocal microscopy. [v1; ref status: indexed, http://f1000r.es/5mr]
No full textHistorically, melanoma has been typically diagnosed by naked-eye examination and confirmed with invasive biopsy. However, recently the use of reflectance confocal microscopy enables non-invasive bedside diagnosis of clinically equivocal lesions. We present a case in which reflectance confocal microscopy was used to evaluate two skin lesions in the same patient confirming the diagnosis of a melanoma and potentially avoiding invasive biopsy in the second benign melanocytic lesion. Clinicians should be aware of the availability of new non-invasive technologies that can aid in early diagnosis of malignant skin tumors and potentially reduce the number of benign lesion excisions
UV radiation effects on algal community structure along a latitudinal gradient
No full textBąk M, Dąbek P, Witkowski A, editors. Abstracts of papers to be presented at the 11th International Phycological Congress; 2017 Aug 13-19; Szczecin, Poland. International Phycological Society; 2017. p. 74. (Phycologia; Vol. 56; No. 4)
Ultrasonic Sensor for Mobile Mini-Robots Using Pseudo-Random Codes
No full textKlahold J, Rautenberg J, Rückert U. Ultrasonic Sensor for Mobile Mini-Robots Using Pseudo-Random Codes. In: Rückert U, Sitte J, Witkowski U, eds. Proceedings of the 5th International Heinz Nixdorf Symposium: Autonomous Minirobots for Research and Edutainment (AMiRE01). Vol 97. Heinz Nixdorf Institut, Universität Paderborn; 2001: 225-232
- …
