2,297 research outputs found
Cryptodacus bernardoi Rodriguez & Rodriguez, new species
No full textCryptodacus bernardoi Rodriguez & Rodriguez, new species Figs. 1, 2, 5 –8, 14, 15, 19, 22, 23, 28 –31, 38– 42 Diagnosis. Modified couplets to the latter are provided to include C. bernardoi. It differs from all other species of Cryptodacus in the strongly sinuous shapes of the apical section of vein R 4 + 5 and crossvein dm-m. It differs from all other species except C. obliquus Hendel in lacking brown markings on the face; from all other species except C. trinotatus by the form of the sublateral postsutural vitta on the scutum, which is almost complete, but interrupted anterior to the intra-alar seta; and from other species except C. tau (Foote) by the entirely yellow abdominal syntergite 1 + 2 (Figs. 22, 23). Other useful diagnostic characters include: gena (Figs. 5, 6,) entirely yellow; posterior side of head yellow except lateral occipital sclerite with elongate brown spot; scutellum with base brown, brown area extended to basal scutellar seta; wing (Fig. 19) cell dm with basal and apical hyaline areas, discal band covering posterior part of crossvein dm-m, middle of dm-m without brown border; abdominal tergites 3–4 with broad brown bands, that on tergite 5 sometimes narrowly divided into 3 parts; oviscape yellow (Figs. 1, 20); aculeus tip with large serrations (Figs. 28–30). Description. Length 4.8 –5.0 mm. Mesonotum length 1.5–1.7 mm. Wing length 3.2–3.5 mm, width 1.3–1.5 mm, length/width ratio: 2.3. Measurements made on holotype female and one paratype male. Head (Figs. 5–8): Mostly pale yellow. Ocellar tubercle brown. Orbital plate with irregular brown stripe. Frons with pair of large dark brown spots aligned with and including base of middle frontal seta. 3 frontal setae; 2 orbital setae, well separated, distance between them 2.3–2.6 times distance from anterior seta to eye margin. Ocellar setae weak, 1.5 –2.0 times length of ocellar tubercle. Lunule entirely dark brown. Face entirely pale yellow, without brown spots; ventral margin strongly arched; gena and postgena entirely pale yellow. Posterior side of head entirely pale yellow except lateral occipital sclerite with elongate brown spot. Clypeus, prementum and palpus entirely yellow. Antenna with scape and pedicel yellow, first flagellomere dark yellow except moderate brown on apex, elongate, 4.5 –5.0 times as long as wide, apex flattened, in lateral view rounded. Arista short pubescent on distal half. Thorax (Figs. 14, 15): Mostly dark brown to black, with following whitish markings: postpronotal lobe and presutural lateral margin of scutum, connected to band on transverse suture; band on transverse suture (interrupted medially), extended across posterior part of notopleuron and posterior margin of anepisternum, almost reaching katepisternum; elongate spot on dorsal margin of katepisternum, not extending to katepisternal seta; single medial and paired sublateral postsutural vittae on scutum, medial vitta short, extended anteriorly almost to level of transverse suture, and posteriorly to midway between levels of acrostichal and dorsocentral setae, lateral vitta connected to band on transverse suture, extending almost to level of postalar seta but not reaching intra-alar seta; rectangular area posterior and lateral to intra-alar seta; and scutellum except base, brown part extending to and including base of basal scutellar seta. Scutum entirely microtrichose. Chaetotaxy normal for genus, postpronotal, 2 notopleural, 1 anepisternal, anepimeral, katepisternal, postsutural supra-alar, intra-alar, postalar, dorsocentral, acrostichal, and 2 scutellar setae well developed. Presutural supra-alar seta relatively small, half to two-thirds size of postsutural supra-alar seta. Dorsocentral seta aligned one-half to two-thirds distance from postsutural supra-alar seta to postalar seta. Legs mostly pale yellow, mid and hind coxae with small lateral brown areas, fore and mid tibiae pale brown, hind tibia dark brown, all tarsi pale brown. Wing (Fig. 19): With 4 bands: subbasal band, entirely brown, extended from cells bc and c to midlength of vein CuA+CuP, covering base of cell br, all of cells bm and bcu, and base of cell m 4 (except bordering fold); discal band, connected to subbasal band in cell c, curved posteriorly and extended to posterior wing margin distally in cell m 4, covering cell r 1 posterior to pterostigma, base of cell r 2 + 3, apex of cell br, crossvein r-m and posterior half of crossvein dm-m, dark brown anteriorly, from cell r 1 to middle of cell dm orange medially with broad, dark brown margins, posterior quarter paler brown; narrow, brown subapical band from distal part of cell r 1 to anterior end of crossvein dm-m, faint in cells r 1 and r 2 + 3; and narrow faint brown anterior apical band from distal part of cell r 2 + 3 to apex of vein M 1. Vein M 4 very narrowly bordered by brown between subbasal and discal bands. Cell dm with anterior apical corner hyaline. Crossvein r-m at 0.71 distance from bm-m to dm-m, entirely covered by dark brown distal margin of discal band. Crossvein dm-m and apical section of vein R 4 + 5 sinuous. Abdomen (female, Figs. 1, 22, male, Figs. 2, 23): Predominantly yellow, including all of syntergite 1 + 2. Tergite 3 with broad dark brown band. Tergite 4 and female tergite 5 with broad dark brown band or series of narrowly separated rectangular marks. Male tergite 5 laterally with paired ovoid brown marks, longer than wide, and medially with much smaller, inverted U-shaped brown mark or pair of brown spots. Female tergite 6 laterally with paired rectangular brown mark, medially usually with two small brown spots. Tergites with sparse black setulae. Female terminalia (Figs. 22, 28– 31): oviscape pale yellow, 0.89–0.92 mm long (n= 2). Aculeus (Fig. 28) 0.60 mm long, tip (Figs. 29, 30) 0.10 mm long, with apical 0.04 mm triangular and serrate, 0.05 mm wide, with 6–9 teeth on each side. Two spermathecae (Fig. 31) subcylindrical, with helical surface texture and elongate base. Male terminalia (Figs. 38–42): epandrium in lateral view wider than long, dorsally dark brown with black setulae, ventrally pale brown. Lateral surstylus in lateral view 3.5 times longer than wide, with glabrous, slightly curved elongated acute apex and distinct anteromedial lobe. Medial surstylus elongate two-thirds as long as lateral surstylus. Proctiger ovoid, entirely membranous, with sparse minute brown setulae. Distiphallus (Figs. 39, 41) moderately long and slender in ventral and lateral views, apex of internal tube bilobed. Type data. Holotype ♀ (IAvH), COLOMBIA: Cundinamarca: Anolaima, Vereda Santo Domingo, finca Villa Mariana [4.80171 °N 74.47542 °W], 1532 m, multilure trap, 3 Sep 2015, P. A. Rodriguez, A. L. Norrbom. Paratypes: COLOMBIA: Cundinamarca: Anolaima, Vereda Santo Domingo, finca Villa Mariana, 1532 m, multilure trap, 3 Sep 2015, P. A. Rodriguez, A. L. Norrbom, 1 ♂ (USNM); same locality, multilure trap, 21 Sep 2015, P. A. Rodriguez, 2 ♀ (ICAMF 00000044); same, multilure trap, 28 Sep 2015, P. A. Rodriguez, 2 ♀ (FSCA); same locality, reared from fruits of Phoradendron sp. near piperoides (Kunth) Trel., collected 13 Sep 2015, emerged 1 Oct 2015, P. A. Rodriguez, 1 ♂ 2 ♀ (USNM). Guaduas, Vereda el Raisal, predio el Cajón km 39 vía Bogotá-Guaduas [5 º07’09”N 74 º 57 ’02”W], 1421 m, McPhail trap 18, 22 Aug 2014, E. Quiroga, 1 ♂ 1 ♀ (ICAMF 00000045). Distribution. Cryptodacus bernardoi is known only from Colombia in Cundinamarca department in the municipios of Anolaima and Guaduas at middle altitudes on the west side of the eastern cordillera. Host plant. Three of the paratypes were reared from tiny fruits of Phoradendron sp. near piperoides (Kunth) Trel. (Figs. 43, 44), which was found parasitizing the upper part of a Psidium guajava L. shrub. This host plant is locally known by the common names “muérdago”, “matapalo”, “injerto” and “pajarito”. Phoradendron is variously classified in the Santalaceae or Viscaceae. The only previous host data for Cryptodacus was the single record of C. silvai Lima from fruit of “herva de passarinho” (Loranthus sp.) from southern Brazil (Lima 1947). The Loranthaceae, Santalaceae (and Viscaceae, when recognized as distinct from Santalaceae) belong to the order Santalales, many of which are parasitic plants. Etymology. This species is named for José Bernardo Rodríguez, father of the senior author. Comments. This species runs with difficulty in the keys of Norrbom (1994) and Norrbom & Korytkowski (2008). C. bernardoi may be most closely related to C. lopezi Norrbom, which has a similar aculeus, or it may belong to a clade along with that species and C. tau and trinotatus. The abdominal pattern is intermediate between those species, which have a distinct medial brown vitta or pair of vittae bordered by white or yellow sublateral areas on at least tergite 5 and female tergite 6, and the predominantly brown pattern in other species. In C. bernardoi the bands on tergites 4–5 in the male and 5–6 in the female may be interrupted. These four species also have the head mostly or entirely yellow posteriorly. The males were described only for C. bernardoi, C. obliquus, C. parkeri and C. tau.Published as part of Rodriguez, Pedro Alexander, Rodriguez, Erick J., Norrbom, Allen L. & Arévalo, Emilio, 2016, A new species and new records of Cryptodacus (Diptera: Tephritidae) from Colombia, Bolivia and Peru, pp. 276-290 in Zootaxa 4111 (3) on pages 277-279, DOI: 10.11646/zootaxa.4111.3.5, http://zenodo.org/record/26487
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
No full textThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Correction to: NG2 antigen is involved in leukemia invasiveness and central nervous system infiltration in MLL-rearranged infant B-ALL (Leukemia, (2018), 32, 3, (633-644), 10.1038/leu.2017.294)
No full textThe original version of this Article contained an error in the spelling of the author Juan Carlos Rodriguez-Manzaneque, which was incorrectly given as J Carlos Rodríguez-Manzaneque. This has now been corrected in both the PDF and HTML versions of the Article
Evolution of the G+C content frontier in the rat cytomegalovirus genome
No full textWithin the 230138 bp of the rat cytomegalovirus (RCMV) genome, the G+C content changes abruptly at position 142644, constituting a G+C content frontier. To the left of this point, overall G+C content is 69.2%, and to the right it is only 47.6%. A region of extremely low G+C content (33.8%) is found in the 5 kb immediately to the right of the frontier, in which there are no predicted coding sequences. To the right of position 147501, the G+C content rises and predicted coding sequences reappear. However, these genes are much shorter (average 848bp, 50% G+C) than those in the left two-thirds of the genome (average 1462bp, 70% G+C). Whole genome alignment of several viruses indicates that the initial ultra-low G+C region appeared in the common ancestor of the genera Cytomegalovirus and Muromegalovirus, and that the lowering of G+C in the right third has been a subsequent process in the lineage leading to RCMV. The left two-thirds of RCMV has stop codon occurrences at 67.5% of their expected level, based on a modified Markov chain model of stop codon distribution, and the corresponding figure for the right third is 78%. Therefore, despite heavy mutation pressure, selective constraint has operated in the right third of the RCMV genome to maintain a degree of gene length unusual for such low G+C sequences
Erratum to “COVID-19 in children: what did we learn from the first waveˮ [Paediatr Child Health 30 (2020) 438–443/1496] (Paediatrics and Child Health (2020) 30(12) (438–443), (S1751722220301591), (10.1016/j.paed.2020.09.005))
No full text\ua9 2021 Elsevier LtdThe publisher regrets that there is an error in author name – “Carlos R. Rodriguez-Martinez” should be changed to Carlos E. Rodriguez-Martinez. The publisher would like to apologise for any inconvenience caused
Gianius navarroi Rodriguez & Achurra, 2010, n. sp.
No full textGianius navarroi n. sp. (Figures 1–2) Phallodrilinae n. sp. in Camacho et al. 2006. Holotype. MNCN 16.03/ 3051. An incomplete mature specimen, stained in Ehrlich’s Haematoxylin and whole-mounted in Canada balsam. Type locality. Ojo Guareña cave (site: “Granja Ortiz”, 1 June 2002), northern Burgos, Spain. UTM coordinates for the Palomera entrance: X: 446595, Y: 4764790, Z: 724. Paratypes. MNCN 16.03/ 3052. A complete mature specimen (unmated) from the type locality, site: “Gour de las Hojas” (8 March 2003). A complete mature specimen in the collection at the University of the Basque Country (UPV/EHU), from the type locality, 11 June 2007. Both specimens are stained in Ehrlich’s Haematoxylin and whole-mounted in Canada balsam. Etymology. Named after the physiologist Dr. Enrique Navarro who has helped P. Rodriguez in sampling numerous sites for the study of aquatic oligochaetes, and has collaborated in applied research with oligochaetes. Description. Length of preserved worms 1.7 mm; number of segments (in two complete specimens) 23 and 26; maximum diameter 150 µm in segment XI. Prostomium rounded, with glandular epidermis (Fig. 1 A). Pygidium short and wide (Fig. 1 B). Body wall consisting of a fine cuticule (ca 1 µm thick), an epidermal layer (5 µm thick) and a relatively poorly developed musculature (2–3 µm thick). Clitellum formed by glands disposed in one layer, from the last third of segment X back to the beginning of segment XII. There is no secondary annulation. One pair of simple spermathecal pores in the most anterior part of segment X, opening in line with ventral chaetae. One pair of male pores in segment XI on porophores, in line with ventral chaetae. All chaetae bifid, 24–27 µm long, with distal tooth shorter than proximal. Anterior segments with 2–5 chaetae per bundle, 2 in postclitellar segments. Chaetal bundles are in the posterior third of the segment. A bundle of 5 penial chaetae forms an arc, towards the sagittal plane of the body (Fig. 2). Penial chaetae straight, with bent distal end, bifid, and of similar length to somatic chaetae. Gianius navarroi A: anterior part of the body in dorso-ventral view, IV–VII: segment number; B: anterior and posterior ends of the body in lateral view; C: segments VII and VIII. Abbreviations: b: brain, cc: chloragogen cells, i: intestine, od: oesophageal diverticula, ph: pharynx, phg: pharyngeal glands, py: pygidium. Scale bars: A and B: 100 µm, C: 50 µm. Brain with two histologically distinct sections: anterior and posterior parts having large nuclei intensely stained with haematoxylin, and a granulated median part that does not stain well. No coelomocytes observed within the coelomic cavity. Pharyngeal glands in segments III–V, dorsal in III, and both lateral and ventral in segments IV and V (in a paratype, glands also ventrally in VI). Chloragogen cells form a layer on the gut from segment VI backwards. In segment VII, a pair of dorsal digestive diverticula, can occupy half or the entire length of the segment, and appear to be attached to the oesophagus at the posterior end of the segment (Figs. 1 A, C). A dilatation of the gut in segment VIII is interpreted as the beginning of the intestine (Figs. 1 B, C). One pair testes in segment X and one pair ovaries in segment XI. Sperm sacs in segment XI (in one specimen spermatogonia and spermatocytes are free in the coelom of segment X). Male ducts paired, with two prostate glands: one ental, close to the junction of the vas deferens with atrium; and other ectal, close to the male pore, much smaller than the ental one. A ciliated vas deferens (6 µm diameter) joins the atrium apically. Atria tubular (77 µm long, up to 15 µm diameter) and curved; thicker in the middle in lateral view (with homogeneous diameter in dorsal view) and gradually narrowing to both ental and ectal ends. The atrial musculature is thin (2–3 µm thick) and the lumen is ciliated or filled with granules (as in Fig. 2). The atria open into salient round porophores (ca 10 µm long), where the penial chaetae are located. Female funnels were not observed. One pair of spermathecae, with a stout duct (20 µm long, 13–16 µm wide) and an elongated globular ampulla (40–50 µm long, 16–17 µm maximum diameter), which contains sperm forming a loop. Distribution and habitat. Gianius navarroi n. sp. is known only from Ojo Guareña cave system, and it is likely to be a stygobiont. The species was collected from two different epikarstic sites within the cave, but was rare, at most one specimen per sample. Habitats sampled were puddles and cave streams, having temporary or permanent water, at depths up to 40 cm; sediment was composed of mud, sand and/or stones. Water temperature was 8.4–9.9ºC, pH 7.8–8.0, dissolved oxygen 74.3–78.4 % saturation and conductivity 389–465 µS/cm. Taxonomic remarks. Gianius navarroi n. sp. has spermathecal pores in line with the ventral chaetae, spermathecae with short ducts, vas deferens entering the apical end of an elongated and curved atrium, and two prostate glands per atrium attached to proximal and distal ends, respectively. All of these characteristics are diagnostic for the phallodriline genus Gianius Erséus, 1992. The presence of digestive diverticula in segment VII was previously known only in the species Gianius labouichensis (Rodriguez and Giani, 1989); although the connection of the diverticula with the gut appears to be in the posterior end of the segment for the new species, whereas for G. labouchensis the single diverticulum connects anteriorly. However, the latter is a distinctive species, well distinguished from other congeners by the lack of penial chaetae, a uniformly tubular atrium with a protrusible pseudopenis, and elongated narrow spermathecal ampulla. The general structure of the male duct in G. navarroi n. sp. is more similar to the remaining species of the genus, being closest to G. aquaedulcis (Hrabë, 1960), G. cavealis Juget and des Chatelliers, 2001 and G. anatolicus Arslan, Timm and Erséus, 2007 based on the thin atrial musculature and the moderate (4–5) number of penial chaetae. Gianius cavealis is well distinguished from the new species by its distal atrial duct well separated from an atrial ampulla, and G. anatolicus by the presence of a long, simple spermathecal duct and three different types of somatic chaetae. The general structure of male duct and spermatheca are similar to G. aquaedulcis, and differences are mainly related to the relative size of the prostate glands (both glands large and of about equal size, in G. aquaedulcis but of visibly different size in the new species), as well as the size of chaetae (41 µm in G. aquaedulcis) and the presence of oesophageal digestive diverticula. The G. aquaedulcis material described by Farara and Erséus (1991) in North America has a larger body size and wider atria (33–38 µm width); it is distinguished from the new species by the absence of noticeable porophores at the male pores, (described as “simple male pore on inconspicuous papilla”), and by the blunt ental end of the atria. The shape of the pygidium in G. n a v a r ro i is unusual, but very similar to that described for Mexidrilus obtusus by Erséus (1992: Fig. 13). Gianius navarroi n. sp. is separated from the previously known species of the genus by the presence of oesophageal diverticula, salient round porophores with the penial chaetae, and marked difference in size of prostate glands (ental gland larger than distal). Isochaetides gianii n. sp. ( Figures 3–5) Lamadrilus sp. in Achurra and Rodriguez (2008) Holotype. MNCN 16.03/ 3053. A dissected worm, stained in Ehrlich’s Haematoxylin and mounted in Canada balsam. Type locality. Apraiz karstic spring (6 September 2005), Santa Eufemia–Ereñozar karst unit, Biscay, Spain. UTM coordinates X: 524225, Y: 4801350, Z: 22. Paratypes. USNM 2052660. A dissected specimen from the type locality (6 September 2005). MNCN 16.03/ 3054: two whole-mounted specimens from Argatxa spring (30 September 2005). In the collection at the University of the Basque Country (UPV/EHU): a sectioned and a dissected specimen from the type locality (6 September 2005); a dissected specimen from Oxiña spring (1 February 1985). All sites in Santa Eufemia– Ereñozar karstic unit, Biscay, Spain. Other material. Three specimens preserved in 70 % alcohol from the type locality (6 September 2005). Two dissected and three specimens in 70 % alcohol, from Argatxa spring (30 September 2005). Four sectioned, seven dissected, two whole-mounted and 17 specimens preserved in 70 % alcohol, from Aulestia spring (23 February 1985). All in the collection at the University of the Basque Country (UPV/EHU). Other localities. Argatxa spring: UTM coordinates X: 527790, Y: 4800925, Z: 2; Oxiña spring: X: 529825, Y: 4801300, Z: 38; Aulestia spring: X: 536494, Y: 4794430, Z: 66. All in Santa Eufemia–Ereñozar karst unit. Etymology. Named after Dr. Narcisse Giani for his important contribution to the taxonomy and general biology of aquatic oligochaetes and also for his important role in the formation of many oligochaete taxonomists (including the first author). Description. Body length 8–10 mm; segment number 59–83; mean body diameter 260 µm (range: 180– 335 µm) in segment V, and 324 µm (225–390 µm) in segment VIII. Prostomium rounded or conical, 75–125 µm long, width about the same or wider at its base (all measurements in fixed individuals). Body wall consisting of a thin cuticle (<1 µm), smooth epidermis (5–10 µm thick, but up to 22 µm in the clitellum) and relatively poorly developed musculature (5–7 µm thick). There is no secondary annulation. Clitellum formed by a single layer of glandular cells, extended from anterior part of XI, back to the line of chaetae in segment XII; no glands in the region between the male pores. One pair of deep folds hiding spermathecal apertures (irregular in shape) in segment X, in line with ventral chaetae. One pair of male pores in segment XI, close to and slightly lateral to the ventral chaetae. In some specimens, the ventral part of segment XI appears deeply retracted by the action of dorso-ventral muscle strands. Ventral chaetae 4–6 per bundle, reduced to two in posterior part of the body, 50–75 μm long, with distal tooth thinner and shorter than proximal (Fig. 3 A, B). Hair and pectinate chaetae in dorsal bundles (Fig. 3 C–E). Hair chaetae in preclitellar region 1–3 (seldom 4) per bundle, 162–262 µm long; in postclitellar region 1–2 per bundle, 75–125 µm long, gradually becoming shorter backwards. Pectinate chaetae in preclitellar segments 2– 4 per bundle, 47–90 µm long and with distal nodulus (at about ⅓ to ¼ from the distal end); 2–3 somewhat shorter chaetae, posteriorly. Teeth of pectinate chaetae about equally long in anterior segments, but distal tooth shorter and thinner than proximal in posterior segments. The number of intermediate teeth in pectinate chaetae 1 or (usually) 2 in anterior dorsal chaetae; intermediate teeth are absent in posterior segments. Modified, distally grooved spermathecal chaetae in segment X, one per bundle, 102–145 µm long and 2– 3 µm thick (Fig. 3 F). There are no modified penial chaetae; 1–2 somatic ventral chaetae per bundle, 50–52 µm long, are found ventrally in segment XI, lateral to the male pores. Brain extends back to 1 / 2. Coelomocytes absent or, if present, they are scarce, small, oval (5 µm maximum diameter), nucleated and granular. Commissural blood vessels connecting dorsal and ventral vessels are visible in most examined specimens; they form several loops in anterior segments, particularly in V (Fig. 4 A). Typical oligochaete dorsal, muscular pharyngeal pad not developed. In segments II–III, pharynx with well-developed epithelium both dorsal and ventrally, and a large mass of glands dorsally (Fig. 4 B). A few clusters of pharingeal glands are located dorso-laterally to the digestive tract in segment IV and laterally in V. A layer of chloragogen cells on the gut extends from segment VI backwards. In segment VIII, oesophagus opens abruptly into the intestine (Fig. 4 C). One pair of spermathecae in segment X. A short spermathecal duct (30–50 µm long, 30–50 µm wide), with a thick epithelium, opens ventrally in segment X at the inner end of a deep epidermal fold (Fig. 4 D, E). Spherical to globular spermathecal ampulla (175–220 µm maximum diameter), with a thin epithelium (3–7 µm high, although up to 20 µm close to the connection with the spermathecal duct). The ampulla usually contains 4–5 drop-like, elongate spermatozeugmata (125–202 µm long, 35–82 µm maximum diameter), which consist of an external clear matrix 7–15 µm thick around an axial cylinder of longitudinally arranged fertilizing sperm (Fig. 4 D). The spermathecal chaetae are orientated with their distal ends towards the spermathecal fold. The proximal end of the chaeta is bent, and associated with a chaetal gland (follicular cells) with several muscular strands; the distal end (ca one third of its total length) is grooved and contained within a chaetophore (32–50 µm diameter), which is internally glandular, radially arranged and externally surrounded by a muscular wall about 2–3 µm thick (Fig. 5). Close to the chaetophore, and most likely functionally associated with it, 1–3 accessory glands can be observed, with histological structure similar to that of the prostate gland. The position of the chaetophore is usually anterior to the spermathecal fold, although in some cases it can be posterior to the fold. One pair testes in X and one pair ovaries in XI. Sperm sacs may extend to IX anteriorly and to XII posteriorly. Egg sac can reach segment XIII. Sperm funnel 80–127 µm high in lateral view (about one third the diameter of the body), attached to septum 10 / 11. Vas deferens ciliated throughout, two to three times longer than the atrium and penis, and restricted to segment XI, where it forms a few loops. It is up to 30 µm in diameter, but thinner in its proximal end (down to 13 µm diameter), and in some specimens also thinner just before its junction with the atrium (15 µm diameter). Atria in XI, tubular (250–300 µm long), bent and expanded near proximal end (42–60 µm, measured at the level of junction with the prostate), thinner in their distal part (30–40 µm), and swelling before entering the penial sac (Fig. 5). Distal section of atrium may be bent, forming a loop before entering the penial sac. Two different types of atrial cells, one forming a dense layer (up to 37 µm high) at the concave side of the atrium, and the other type with a clear granulated appearance forming a layer of cells (up of 20 µm high) along the convex side and the proximal part of the atrium. Atrial musculature very thin (<2 µm thick) and atrial lumen narrow, 2–5 µm. A medium-size, compact prostate gland connects by a short stalk to the concave side, at the proximal expanded end of the atrium. Vas deferens enters subapically on the convex side of the atrium. Penial sac well developed, oval, with maximum diameter parallel to the longitudinal axis of the body (115–145 µm), having a ring fold at its inner end. Penis cylindrical (65–115 µm long and 35–50 µm diameter) and formed by two epithelial layers (Fig. 4 F–H). A mushroom-shaped cuticular layer, consisting of an inner oval part (2–4 µm thick) lining both the penial sac and the proximal ring fold; and a central stalk (1–2 µm thick) forming a cuticular sheath around the penis. This penial sheath is slightly conical and encloses most of the penis, which is free inside it and can project partially outwards. Female funnels were not observed. Teratology. One specimen with two male ducts plus one spermatheca on one side, and one male duct, one spermatheca plus two chaetophores on the other side. Distribution and habitat. The new species was found in four karstic springs located in the karst of Santa Eufemia-Ereñozar, in sandy sediments. Water characteristics were for Argatxa spring: 13.7ºC, pH 7.2, 446 µS/ cm and 91 % dissolved oxygen; and for Apraiz spring: 14.8ºC, pH 7.0, 469 µS/cm and 70 % dissolved oxygen. Taxonomic remarks. The position and general structure of the gonads, male ducts and spermathecae in the new species are characteristic of the oligochaetes of the subfamily Tubificinae. The new species is related to the tubificine genera Isochaetides Hrabë, 1966 and Lamadrilus Timm, 1998 by the presence of a tubular atrium, a discrete prostate gland attached to atrium by a narrow stalk, a vas deferens longer than the atrium and ciliated throughout, a penis within a penial sac, and modified spermathecal chaetae. Other close genera with similar characteristics of the male duct are Tasserkidrilus, Arctodrilus, Troglodrilus and Haber, the first three lacking modified genital setae, and the latter with both spermathecal and penial chaetae modified. The new species has modified spermathecal setae in X and no penial chaetae, as well as a general structure of the male duct which can be present in either Isochaetides or Lamadrilus. These include the vas deferens joining the atrium subapically, and the expanded proximal end of the atrium, which has two layers of glandular cells: a dark, densely granulated layer in the concave side and a light layer in the convex side. The new species is well distinguished from other species of Isochaetides or Lamadrilus by a combination of characters that include: hair chaetae and pectinates in dorsal bundles, grooved spermathecal chaetae associated with chaetophores and glands, a well-developed penial sac lined by a cuticle layer with a proximal ring fold, and a cuticular penial sheath (not asymmetrical or in the form of a spade). Due to the feeble differences between the genera Isochaetides and Lamadrilus, the new species was first identified as Lamadrilus sp. (Achurra & Rodriguez 2008), mainly based on the presence of hair chaetae. Most species in this genus have only bifid somatic chaetae, except L. bazikalovae (Chekanovskaya, 1975), which presents different rates of reduction in hair chaetae and pectinates (Timm 1998). However, we agree with Brinkhurst and Kathman (1983) that the absence of species with hair chaetae in a genus should not be a problem for the inclusion of a new species with hair chaetae; and I. gianii n. sp. has been classified on the basis of the structure of the reproductive organs. The genus Isochaetides Hrabë, 1966 includes species that possess modified spermathecal chaetae (except I. distinctus Semernoy, 2001). These are characteristically grooved in the distal end (except for I. michaelseni Lastočkin, 1937, which has bifid genital chaetae), and generally appear associated with spermathecal glands. In several species, these glands are poorly described, but their remarkable distal position with respect to the spermathecal chaeta, and their structure (sometimes only seen in drawings), is similar to the chaetophores that we have described in I. gianii n. sp. Chaetophores associated with spermathecal chaetae are also known in other oligochaete genera [e.g. the rhyacodriline Protuberodrilus tourenqui Giani & Martínez-Ansemil, 1979 and the telmatodriline Alexandrovia ringulata (Sokolskaya, 1961)]. On the other hand, only one of the six known species of Lamadrilus (L. sorosi Timm, 1998) has modified spermathecal chaetae of the same type as that described in Isochaetides species, as well as a chaetophore and accessory glands associated to the chaetal sac. The two different epithelial layers of the atrium described in the new species are probably equivalent to the dark and light layers described in L. sorosi by Timm (1998), and are also reminiscent of the layers shown in drawings of some Isochaetides species. This histological characteristic has been confirmed in the examination of type specimens of I. freyi (Brinkhurst, 1965) (Fig. 6 A), although it has probably been overlooked in most descriptions, not only in species of these genera but also in other tubificines. The presence of a penial sac with an apical ring fold is known in other Isochaetides species (e.g. I. freyi) (Fig. 6 B). Several lateral folds are present in the penial sac of some Lamadrilus species (e.g. L. sorosi), but never in the form of an ental ring fold. The presence of a short, mostly asymmetrical cuticular penial sheath (sometimes with a spade-shaped distal appendage) is a diagnostic character in Lamadrilus; however, the genus incorporates different types of penial sheaths (sometimes variable in shape within the same species, with a more or less marked asymmetry, see Timm, 1998: Figs. 45–50). The diagnosis of the genus Isochaetides by Snimschikova (1998) describes the cuticular penial sheath as thin or absent and Semernoy (2004) describes it as more or less thin, either of uniform width or conical but without oblique cut on its distal end. In fact, all Isochaetides species known to date, except for I. lacustris, have a thin cuticular penial sheath or a thin cuticular covering on the penis (although thick in I. distinctus Semernoy, 2004). The examination of the type specimens of I. freyi have revealed a conspicuous cuticular layer, covering the inner side of the penial sac, the large ental fold and the penis, and taking the shape of their contour (Fig. 6 B), in a similar way to that in the new species. The structure of the spermatheca is not commonly used as a diagnostic character in tubificines. However, in Isochaetides the short spermathecal ducts, associated with modified spermathecal chaetae located in adjacent glandular sacs (referred to as chaetophores in present work), appear to be a very common feature. The structure of the spermathecal duct is contentious and what is described here as a short spermathecal duct opening at the ental end of a ventr
Publisher Correction: Fe-functionalized paramagnetic sporopollenin from pollen grains: one-pot synthesis using ionic liquids (Scientific Reports, (2020), 10, 1, (12005), 10.1038/s41598-020-68875-6)
No full textIn the original version of this Article, F. Rossella was incorrectly listed as a corresponding author. The correct corresponding author for this Article is C.S. Pomelli. Correspondence and request for materials should be addressed to [email protected]. This error has now been corrected in the HTML and PDF versions of the Article
On The Role Of Soft Inclusions On The Fracture Behaviour Of Cement Paste
No full textSoft inclusions, such as capsules and other particulate admixtures are increasingly being used in cementitious materials for functional purposes (i.e. self-healing and self-sensing of concrete). Yet, their influence on the fracture behaviour of the material is sometimes overlooked and requires in-depth study for the optimization of mechanical and/or smart properties. An experimental investigation is presented herein on the role of bacteria-based lactate-derived particles on the fracture behaviour of cement paste in tensile configuration. These admixtures are currently used for the purpose of self-healing. Digital Image Correlation was used to obtain strain contours on the surface of the samples during the test. The influence of soft particles addition and age of the samples on the fracture mechanics of the composite were investigated
Is the debt crisis history? Recent private capital inflows to developing countries
No full textThe outlook for economic development for an important group of middle-income countries has again been buoyed by substantial private capital inflows in the 1990s. As in the 1970s, this development has been met with cautious optimism. It is generally accepted that these countries need resource transfers from the rest of the world to support capital formation and growth. It is also generally accepted that these private capital flows make the allocation of resources more efficient. But there is concern that a rapid reversal of market sentiment could impose considerable adjustment costs on these same economies. The authors try to quantify what many consider to be the main reasons debtor countries have access to capital markets again: (a) Domestic policy reform in the debtor countries. (b) Debt and debt service reduction, usually associated with Brady Plan restructuring. (c) Changes in the external market, such as changes in interest rates in industrial countries. They argue that a useful barometer for access to new loans is the market value of existing sovereign debt. It follows that a quantitative analysis of the factors that caused the market value of sovereign debts to rise rapidly after 1989 would also improve understanding of the forces behind the renewed access to international capital. Empirical historical evidence suggests that fiscal reform, privatization, and debt reduction are useful in explaining relative improvements in the standing of debtor countries in international credit markets. Debtor countries with strong reform programs, in other words, are better prepared to withstand deterioration in the external environment. But the reduction in dollar interest rates since 1989 appears to be the chief factor in the debtor countries'renewed access to international loans. The authors estimate the effect of increases in dollar interest rates and conclude that the typical debtor country remains vulnerable to increases in interest rates that are well within the range of recent experience.Economic Theory&Research,Environmental Economics&Policies,Banks&Banking Reform,Strategic Debt Management,Financial Intermediation
A simple method for screening bacterial colonies for mutagenized sites in plasmid DNA
No full textBecause of the multiple-step process that is involved in the detection of mutagenized restriction enzyme sites in plasmid DNA, a simple and accurate method was developed to analyse the plasmid DNA of site-directed mutagenesis experiments from bacterial colonies. The desired mutated part is located between the Eco RI restriction site on pUC19. Two mutagenic primers were designed to replace only one nucleotide on segments A and B of the bi-segmented genome of infectious bursal disease virus (IBDV). Two restriction sites were created for those mutations in each segment, Fsp I and Dra I, respectively. Following a protocol from the site-directed mutagenesis kit, the mutated plasmids were used to transform, and were propagated and maintained in DH5 alpha competent cells. Colonies were picked from the master plate, and used as DNA template for PCR. The PCR technique included the design of two pairs of primers, one for each segment, which were to amplify a region up to 1000 bp. Samples were pre-incubated for 3 min at 94 degrees C to induce bacterial lysis before starting the nucleic acid amplification. The PCR products 918 bp from segment A and 650 bp from segment B were digested with Fsp I and Dra I at 37 degrees C for 1 h. Products were resolved on 0.9% agarose gel which contained ethidium bromide. This method is simpler, faster and more accurate than the traditional method of mini-prep plasmid isolation and colony blot hybridization to identify the mutated plasmids
- …
