8,004 research outputs found
Biography of Ceerno Ndiaye Ba
No full textThis manuscript is a biography of Ceerno Ndiaye Ba Bababe, in Mauritania. It is one of a series of biographies that the author has written about Islamic leaders in West Africa.Ce manuscrit est une biographie de Ceerno Ndiaye Ba Bababe, en Mauritanie. Elle fait partie d'une série de biographies que l'auteur a écrites sur les dirigeants islamiques en Afrique de l'Ouest
Poems of Sheikh Muhammad al-Ghaly Ba
No full textThis volume contains seven poems handwritten by Muhammad al-Ghāli Ba. According to the author's son, Mountaga Ba, the poems were probably composed in the mid-1970s a time when the author lived in Mauritania, while working at the country's national radio station and serving as a special counsel to then president Moktar Ould Daddah (1924–2003). The poems adress various issues. The first is a call to action addressed to the Mauritianian youth, urging them to join in the collective work for the development of the country. The second poem is a hagiography on Ceerno Ahmad Nene Ba of Kaedi (Mauritania). The poem eulogizes the virtues of the patron. The third describes the event of Sharif Muhammad al-Habib's visit to the region of Fuuta region (Senegal), namely the village of Pate Galo. The fourth poem contains greetings and expresions of love addressed to the author's friends in the town of Kaedi. The fifth poem is a remembrance about good times. The author reminisces and praises the qualities of a woman named Jaari.The sixth poem describes one afternoon journey of the author. The seventh poem is a mournful praisesong in which the author laments the loss of a cherished person.Ce volume contient sept poèmes manuscrits de Muhammad al-Ghāli Ba. Selon le fils de l'auteur, Mountaga Ba, les poèmes ont probablement été composés au milieu des années 1970, à une époque où l'auteur vivait en Mauritanie, alors qu'il travaillait à la radio nationale du pays et était conseiller spécial du président de l'époque, Moktar Ould Daddah (1924). –2003). Les poèmes abordent diverses questions. Le premier est un appel à l'action adressé aux jeunes mauriciens, les exhortant à s'associer au travail collectif pour le développement du pays. Le deuxième poème est une hagiographie sur Ceerno Ahmad Nene Ba de Kaedi (Mauritanie). Le poème fait l'éloge des vertus du mécène. Le troisième décrit l'événement de la visite de Sharif Muhammad al-Habib dans la région de la région de Fuuta (Sénégal), à savoir le village de Pate Galo. Le quatrième poème contient des salutations et des expressions d'amour adressées aux amis de l'auteur dans la ville de Kaedi. Le cinquième poème est un souvenir des bons moments. L'auteur rappelle et loue les qualités d'une femme nommée Jaari. Le sixième poème décrit un après-midi de voyage de l'auteur. Le septième poème est une louange mélancolique dans laquelle l'auteur déplore la perte d'une personne chérie
Meriania zunacensis D. Fernandez & Dellinger, Phytotaxa
No full text<p> <b>36.</b> <i>Meriania zunacensis</i> D.Fernández & Dellinger, Phytotaxa 458(1): 7 (2020).</p> <p> Type:— <b>ECUADOR. Tungurahua:</b> Cantón Baños, Parroquia Río Negro, Sector El Topo, Estación Cientifica Río Zuñac, Fundación EcoMinga, 1568 m, 01°22.593’S, 78°09.213’W, 26 May 2018 (fl., fr.), <i>L. Jost, F. Recalde & S. Recalde 10600</i> (holotype: QCNE! [barcodes 243978 – 1/2, 243977 – 2/2]; isotype: QCNE! [barcode 243976]). (Figures 72–73).</p> <p> <b>Comments:—</b> Among Peruvian species of <i>Meriania</i>, it is distinguishable by combination of quadrangular and ribbed internodes, nodes with interpetiolar flaps (Fig. 72D), an adaxial projection (scutum) on the transition zone from the petiole to the midvein (Fig. 73A), leaf blades with flat adaxial surfaces, spreading, reddish-purple corollas, isomorphic stamens, and pyriform mature ovaries (Fig. 73D). Among Peruvian species, <i>M. zunacensis</i> most closely resembles <i>M. callosa</i> and <i>M. megaphylla</i> (see comments under these species for differences).A detailed comparison of <i>M. zunacensis</i> with other related species can be found in Fernández-Fernández <i>et al.</i> (2020) and Fernandez-Hilario <i>et al.</i> (2022).</p> <p> <b>Distribution and phenology:—</b> <i>Meriania zunacensis</i> occurs in Ecuador and northern Peru (Department of Amazonas in montane forests at 1500–2280 m) (Fig. 35). It has been collected in flower in February, June and July, and in fruit in February and July.</p> <p> <b>Specimens examined:—</b> <b>PERU. Amazonas:</b> Prov.Amazonas, Dist. Vista Alegre, entre Vista Alegre y La Ventana a Naciento del Río Negro, 1500–1640 m, 06°08’S, 77°18’W, 02 Jul 1998 (fl., fr.), <i>I. Sánchez et al. 9610</i> (CPUN!, F!); Prov. Bagua, La Peca, 1850–1900 m, 14 Jun 1978 (fl. bud), <i>A. Gentry et al. 23012</i> (USM!, US!); Prov. Bongará, Dist. Yambrasbamba, inmediaciones de la Estación Biológica Abra Patricia, trochas cercanas a la estación, 2280 m, 05°41’43.40”S, 77°48’47.91”W, 19–20 Feb 2020 (fl., fr.), <i>R. Fernandez-Hilario et al. 1920</i> (HOXA!, KUELAP!, MOLF!, NY!, UPCB!), trocha Lechuza en la Estación Biológica Abra Patricia, 2123 m, 05°41’18.89”S, 77°48’23.68”W, 21 Feb 2020 (fl.), <i>R. Fernandez-Hilario et al. 1938</i> (HOXA!, MOLF!, UPCB!).</p>Published as part of <i>Fernandez-Hilario, Robin, Goldenberg, Renato & Michelangeli, Fabián A., 2023, A synopsis of Meriania (Melastomataceae: Merianieae) in Peru, pp. 1-101 in Phytotaxa 602 (1)</i> on page 92, DOI: 10.11646/phytotaxa.602.1.1, <a href="http://zenodo.org/record/8141984">http://zenodo.org/record/8141984</a>
In silico evaluation of the impact of Omicron variant of concern sublineage BA.4 and BA.5 on the sensitivity of RT-qPCR assays for SARS-CoV-2 detection using whole genome sequencing
No full textBackground: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern (VoC) Omicron (B.1.1.529) has rapidly spread around the world, presenting a new threat to global public human health. Due to the large number of mutations accumulated by SARS-CoV-2 Omicron, concerns have emerged over potentially reduced diagnostic accuracy of reverse transcription polymerase chain reaction (RT-qPCR), the gold standard diagnostic test for diagnosing coronavirus disease 2019 (COVID-19). Thus, we aimed to assess the impact of the currently endemic Omicron sublineages BA.4 and BA.5 on the integrity and sensitivity of RT-qPCR assays used for coronavirus disease 2019 (COVID-19) diagnosis via in silico analysis. We employed whole genome sequencing data and evaluated the potential for false negatives or test failure due to mismatches between primers/probes and Omicron VoC viral genome. Methods: In silico sensitivity of 12 RT-qPCR tests (containing 30 primers and probe sets) developed for detection of SARS-CoV-2 reported by the World Health Organization (WHO) or available in the literature, was assessed for specifically detecting SARS-CoV-2 Omicron BA.4 and BA.5 sublineages, obtained after removing redundancy from publicly available genomes from National Center for Biotechnology Information (NCBI) and Global Initiative on Sharing Avian Influenza Data (GISAID) databases. Mismatches between amplicon regions of SARS-CoV-2 Omicron VoC and primers and probe sets were evaluated, and clustering analysis of corresponding amplicon sequences was carried out. Results: From the 1164 representative SARS-CoV-2 Omicron VoC BA.4 sublineage genomes analyzed, a substitution in the first five nucleotides (C to T) of the amplicon's 3' end were observed in all samples resulting in 0% sensitivity for assays HKUnivRdRp/Hel (mismatch in reverse primer) and CoremCharite N (mismatch in both forward and reverse primers). Due to a mismatch in the forward primer's 5' end (3-nucleotide substitution, GGG to AAC), the sensitivity of ChinaCDC N assay was at 0.69%. The 10 nucleotide mismatches in the reverse primer resulted in 0.09% sensitivity for Omicron sublineage BA.4 for Thai N assay. Of the 1926 BA.5 sublineage genomes, HKUnivRdRp/Hel assay also had 0% sensitivity. A sensitivity of 3.06% was observed for ChinaCDC N assay because of a mismatch in the forward primer's 5' end (3-nucleotide substitution, GGG to AAC). Similarly, due to the 10 nucleotide mismatches in the reverse primer, Thai N assay's sensitivity was low at 0.21% for sublineage BA.5. Further, 8 assays for BA.4 sublineage retained high sensitivity (more than 97%) and 9 assays for BA.5 sublineage retained more than 99% sensitivity. Conclusion: We observed four assays (HKUnivRdRp/Hel, ChinaCDC N, Thai N, CoremCharite N) that could potentially result in false negative results for SARS-CoV-2 Omicron VoCs BA.4 and BA.5 sublineages. Interestingly, CoremCharite N had 0% sensitivity for Omicron Voc BA.4 but 99.53% sensitivity for BA.5. In addition, 66.67% of the assays for BA.4 sublineage and 75% of the assays for BA.5 sublineage retained high sensitivity. Further, amplicon clustering and additional substitutions analysis along with sensitivity analysis could be used for modification and development of RT-qPCR assays for detecting SARS-CoV-2 Omicron VoC sublineages. This article is protected by copyright. All rights reserved
Longitudinal analysis of serum neutralization of SARS-CoV-2 Omicron BA.2, BA.4, and BA.5 in patients receiving monoclonal antibodies
No full textThe emergence of Omicron sublineages impacts the therapeutic efficacy of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) monoclonal antibodies (mAbs). Here, we evaluate neutralization and antibody-dependent cellular cytotoxicity (ADCC) activities of 6 therapeutic mAbs against Delta, BA.2, BA.4, and BA.5. The Omicron subvariants escape most antibodies but remain sensitive to bebtelovimab and cilgavimab. Consistent with their shared spike sequence, BA.4 and BA.5 display identical neutralization profiles. Sotrovimab is the most efficient at eliciting ADCC. We also analyze 121 sera from 40 immunocompromised individuals up to 6 months after infusion of Ronapreve (imdevimab + casirivimab) or Evusheld (cilgavimab + tixagevimab). Sera from Ronapreve-treated individuals do not neutralize Omicron subvariants. Evusheld-treated individuals neutralize BA.2 and BA.5, but titers are reduced. A longitudinal evaluation of sera from Evusheld-treated patients reveals a slow decay of mAb levels and neutralization, which is faster against BA.5. Our data shed light on antiviral activities of therapeutic mAbs and the duration of effectiveness of Evusheld pre-exposure prophylaxis
Seawater nutrient and carbonate ion concentrations recorded as P/Ca, Ba/Ca, and U/Ca in the deep-sea coral D. dianthus
No full textAs paleoceanographic archives, deep sea coral skeletons offer the potential for high temporal resolution and precise absolute dating, but have not been fully investigated for geochemical reconstructions of past ocean conditions. Here we assess the utility of skeletal P/Ca, Ba/Ca and U/Ca in the deep sea coral D. dianthus as proxies of dissolved phosphate (remineralized at shallow depths), dissolved barium (trace element with silicate-type distribution) and carbonate ion concentrations, respectively. Measurements of these proxies in globally distributed D. dianthus specimens show clear dependence on corresponding seawater properties. Linear regression fits of mean coral Element/Ca ratios against seawater properties yield the equations: P/Cacoral (lmol/mol) = (0.6 ± 0.1) P/Casw(lmol/mol) – (23 ± 18), R2 = 0.6, n = 16 and Ba/Cacoral(lmol/mol) = (1.4 ± 0.3) Ba/Casw(lmol/mol) + (0 ± 2), R2 = 0.6, n = 17; no significant relationship is observed between the residuals of each regression and seawater temperature, salinity, pressure, pH or carbonate ion concentrations, suggesting that these variables were not significant secondary dependencies of these proxies. Four D. dianthus specimens growing at locations withOarag 6 0.6 displayed markedly depleted P/Ca compared to the regression based on the remaining samples, a behavior attributed to an undersaturation effect. These corals were excluded from the calibration. Coral U/Ca correlates with seawater carbonate ion: U/Cacoral(lmol/mol) = (?0.016 ± 0.003) ½CO2? 3 ? (lmol/kg) + (3.2 ± 0.3), R2 = 0.6, n = 17. The residuals of the U/Ca calibration are not significantly related to temperature, salinity, or pressure. Scatter about the linear calibration lines is attributed to imperfect spatialtemporal matches between the selected globally distributed specimens and available water column chemical data, and potentially to unresolved additional effects. The uncertainties of these initial proxy calibration regressions predict that dissolved phosphate could be reconstructed to ±0.4 lmol/kg (for 1.3–1.9 lmol/kg phosphate), and dissolved Ba to ±19 nmol/kg (for 41–82 nmol/kg Basw). Carbonate ion concentration derived from U/Ca has an uncertainty of ±31lmol/kg (for 60–120 lmol=kg CO2? 3 ). The effect of microskeletal variability on P/Ca, Ba/Ca, and U/Ca was also assessed, with emphasis on centers of calcification, Fe–Mn phases, and external contaminants. Overall, the results show strong potential for reconstructing aspects of water mass mixing and biogeochemical processes in intermediate and deep waters using fossil deep-sea corals
Boundary Algebra: A Simpler Approach to Boolean Algebra and the Sentential Connectives
No full textBoundary algebra [BA] is a algebra of type , and a simplified notation for Spencer-Brown’s (1969) primary algebra. The syntax of the primary arithmetic [PA] consists of two atoms, () and the blank page, concatenation, and enclosure between ‘(‘ and ‘)’, denoting the primitive notion of distinction. Inserting letters denoting, indifferently, the presence or absence of () into a PA formula yields a BA formula. The BA axioms are A1: ()()= (), and A2: “(()) [abbreviated ‘⊥’] may be written or erased at will,” implying (⊥)=(). The repeated application of A1 and A2 simplifies any PA formula to either () or ⊥. The basis for BA is B1: abc=bca (concatenation commutes & associates); B2, ⊥a=a (BA has a lower bound, ⊥); B3, (a)a=() (BA is a complemented lattice); and B4, (ba)a=(b)a (implies that BA is a distributive lattice). BA has two intended models: (1) the Boolean algebra 2 with base set B={(),⊥}, such that () ⇔ 1 [dually 0], (a) ⇔ a′, and ab ⇔ a∪b [a∩b]; and (2) sentential logic, such that () ⇔ true [false], (a) ⇔ ~a, and ab ⇔ a∨b [a∧b]. BA is a self-dual notation, facilitates a calculational style of proof, and simplifies clausal reasoning and Quine’s truth value analysis. BA resembles C.S. Peirce’s graphical logic, the symbolic logics of Leibniz and W.E. Johnson, the 2 notation of Byrne (1946), and the Boolean term schemata of Quine (1982).Boundary algebra; boundary logic; primary algebra; primary arithmetic; Boolean algebra; calculation proof; G. Spencer-Brown; C.S. Peirce; existential graphs
Monitoring of the SARS-CoV-2 Omicron BA.1/BA.2 lineage transition in the Swedish population reveals increased viral RNA levels in BA.2 cases
No full textBACKGROUND: Throughout the SARS-CoV-2 pandemic, multiple waves of variants of concern have swept across populations, leading to a chain of new and yet more contagious variants dominating COVID-19 cases. Here, we tracked the remarkably rapid shift from Omicron BA.1 to BA.2 sublineage dominance in the Swedish population in early 2022 at a day-by-day basis. METHODS: Using a custom SARS-CoV-2 Omicron BA.1 lineage-typing RT-PCR assay, we analyzed 174,933 clinical upper airway samples collected during January to March 2022. FINDINGS: Our study demonstrates the feasibility and reliability of parallel lineage assignment of select variants at population scale, tracking the dominant sublineage transition from BA.1 to BA.2 at day-to-day resolution and uncovering nearly 2-fold higher levels of viral RNA in cases infected with Omicron BA.2 relative to BA.1. CONCLUSIONS: Our data provide unique insights into the Omicron BA.1 to BA.2 transition that occurred in Sweden during early 2022, and later, across the world. This may help to understand the increased transmissibility of the BA.2 variant
- …
