140 research outputs found
Jabarichromis Haefeli & Schedel & Ronco & Indermaur & Salzburger 2024, gen. nov.
No full textGenus <i>Jabarichromis</i> gen. nov. <p> <b>Type Species.</b> <i>Paratilapia pfefferi</i> (Boulenger 1898)</p> <p> <b>Diagnosis.</b> <i>Jabarichromis</i> <b>gen. nov.</b> can be identified as a member of the Tropheini, which are nested within the Haplochromini (Ronco <i>et al.</i> 2021; Salzburger <i>et al.</i> 2005), by the definition from Takahashi (2003): “extensively granulated cycloid scales at midbody (granulations comprising irregularly arranged, variously shaped protrusions over almost entire exposed surface)”.A revision or specification of this definition is needed because all our specimens show additional scales with small ctenii along the midbody, increasing in numbers towards the ventral and posterior side. This state for <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i> was also reported by Genner <i>et al.</i> (2022). Further, ctenoid scales along the midbody for species belonging to the Tropheini were reported by Viertler <i>et al.</i> (2021).</p> <p> <i>Jabarichromis</i> <b>gen. nov.</b> can be distinguished from the other genera within the Tropheini by their longer premaxilla height (except <i>Lobochilotes</i> Boulenger 1915) as well as their longer lower jaw length (except <i>Lobochilotes</i> and <i>Shuja</i>). It is distinguishable from <i>Lobochilotes</i> by the total number of vertebrae (29 in <i>Lobochilotes</i> and 30 in <i>Jabarichromis</i> <b>gen. nov.</b>), the total number of gill rakers (22–27 in <i>Lobochilotes</i> and 15–18 in <i>Jabarichromis</i> <b>gen. nov.</b>), the number of scales between the upper lateral line and the dorsal fin origin (7–9 in <i>Lobochilotes</i> and 5–6 in <i>Jabarichromis</i> <b>gen. nov.</b>), and the number of pectoral rays (16–17 in <i>Lobochilotes</i> and 13–15 in <i>Jabarichromis</i> <b>gen. nov.</b>). Further, it is distinguishable from <i>Shuja</i> by the number of scales between the upper lateral line and the last dorsal fin spine (2 in <i>Shuja</i> and 3 in <i>Jabarichromis</i> <b>gen. nov.</b>).</p> <p> Finally, <i>Jabarichromis</i> <b>gen. nov.</b> is distinguishable from <i>Gnathochromis</i> and its only remaining member <i>G. permaxillaris</i> by the premaxilla height (58%–63% in head length in <i>G. permaxillaris</i> and 46%–51% of head length in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), dorsal fin length (DFL) (51%–55% in standard length in <i>G. permaxillaris</i> and 56%–61% of standard length in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), premaxilla length (41%–48% in head length in <i>G. permaxillaris</i> and 30%–36% of head length in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), the number of total vertebrae (31– 31 in <i>G. permaxillaris</i> and 29 in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), the number of total gill rakers (24–27 in <i>G. permaxillaris</i> and 15–18 in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), the number of scales on horizontal line (33–34 in <i>G. permaxillaris</i> and 29–31 in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>), and number of scales on upper lateral line (25–30 in <i>G. permaxillaris</i> and 20–23 in <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>).</p> <p> <b>Description.</b> <i>Jabarichromis</i> <b>gen. nov.</b> currently comprises one species, <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i>, which is endemic to Lake Tanganyika. The premaxilla height reaches 46%–51%, the lower jaw length 13%–15% and the premaxilla length ranges from 30%–36% of head length; the dorsal fin length ranges from 56%–62% of the standard length. The number of vertebrae is 29 (14–15 abdominal, 14–15 caudal); the total number of gill rakers ranges from 15–18; the number of scales between the upper lateral line and the dorsal fin origin ranges from 5–6; the number of scales between the upper lateral line and last dorsal fin spine is 3. The number of scales on the horizontal line ranges from 29–31 and the number of scales on the upper lateral line reaches from 20–23. The number of pectoral rays is 13–15. Like all members of the Tropheini <i>Jabarichromis</i> <b>gen. nov.</b> are mouthbrooders (Konings 2019; Takahashi 2003). The total length can reach up to 14 cm (Konings 2019).</p> <p> <b>Etymology.</b> The genus name is derived from the Swahili word “Jabari” which is translated into English as “brave one” or “emperor”, “ruler”. It is referring to <i>Jabarichromis</i> <b>gen. nov.</b> <i>pfefferi</i> ’s hunting behaviour as well as their large hunting territories which can reach up to 500m 2 (Konings 2019). “Chromis” is an Ancient Greek word for fish and refers to a widely used suffix for cichlid genera. The gender of <i>Jabarichromis</i> <b>gen. nov.</b> is masculine.</p> <p> <b>Included species.</b> <i>Jabarichromis pfefferi</i> (Boulenger 1898)</p> <p> <i>Paratilapia pfefferi</i> Boulenger, 1898</p> <p> <i>Limnochromis pfefferi</i> (Boulenger), Regan, 1920</p> <p> <i>Haplochromis pfefferi</i> (Boulenger), Poll, 1974</p> <p> <i>Gnathochromis pfefferi</i> (Boulenger), Poll, 1981</p>Published as part of <i>Haefeli, Anja, Schedel, Frederic D. B., Ronco, Fabrizia, Indermaur, Adrian & Salzburger, Walter, 2024, Revision of the cichlid fish genus Gnathochromis (Teleostei: Cichlidae) from Lake Tanganyika with the description of a new genus Jabarichromis gen. nov., pp. 434-450 in Zootaxa 5410 (3)</i> on pages 444-445, DOI: 10.11646/zootaxa.5410.3.10, <a href="http://zenodo.org/record/10657342">http://zenodo.org/record/10657342</a>
Observations of Bºs→ψ(2S)η and Bº(s)→ψ(2S)π+π- decays
No full textFirst observations of the B0s
→ψ(2S)η, B0 →ψ(2S)π
+
π
− and B0s
→ψ(2S)π
+
π
− decays are made
using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment in
proton–proton collisions at a centre-of-mass energy of
√
s = 7 TeV. The ratios of the branching fractions
of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are
B(B0s
→ψ(2S)η)
÷
B(B0s
→J/ψη)
= 0.83± 0.14 (stat)±0.12 (syst) ±0.02 (B),
;
B(B0→ψ(2S)π
+
π
−
)
÷
B(B0→J/ψπ
+
π
−
)
= 0.56± 0.07 (stat)±0.05 (syst)± 0.01 (B),
;
B(B0s
→ψ(2S)π
+
π
−
)
÷
B(B0s
→J/ψπ
+
π
−
)
= 0.34± 0.04 (stat)±0.03 (syst)± 0.01 (B),
where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ
and ψ(2S) meson decays
Measurement of the effective B_s^0 -> J/ψ K_S^0 lifetime
No full textThis paper reports the first measurement of the effective B_s^0 -> J/{\psi} K_S^0 lifetime and an updated measurement of its time-integrated branching fraction. Both measurements are performed with a data sample, corresponding to an integrated luminosity of 1.0 fb^{-1} of pp collisions, recorded by the LHCb experiment in 2011 at a centre-of-mass energy of 7 TeV. The results are: tau_J/{\psi}K_S^0 = 1.75 +/- 0.12 (stat) +/- 0.07 (syst) and BR(B_s^0 -> J/{\psi} K_S^0) = (1.97 +/- 0.23) X 10^{-5}.
For the latter measurement, the uncertainty includes both statistical and systematic sources
Using micropower impulse radar technology to screen for pneumothorax: an international bi-institutional study. Corrigendum
No full textIn an article in the December 2012 issue of The Journal of Trauma and Acute Care Surgery, several author names were misprinted
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Prompt charm production in pp collisions at √<span style="text-decoration:overline">s</span>=7 TeV
No full textCharm production at the LHC in pp collisions at s√=7 TeV is studied with the LHCb detector. The decays D0→K−π+, D+→K−π+π+, D⁎+→D0(K−π+)π+, D+s→ϕ(K−K+)π+, Λ+c→pK−π+, and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb−1. Differential cross-sections dσ/dpT are measured for prompt production of the five charmed hadron species in bins of transverse momentum and rapidity in the region 0<pT<8 GeV/c and 2.0<y<4.5. Theoretical predictions are compared to the measured differential cross-sections. The integrated cross-sections of the charm hadrons are computed in the above pT-y range, and their ratios are reported. A combination of the five integrated cross-section measurements gives
σ(cc¯)pT<8 GeV/c,2.0<y<4.5=1419±12(stat)±116(syst)±65(frag) μb,
where the uncertainties are statistical, systematic, and due to the fragmentation functions
Measurement of the Xi(-)(b) and Omega(-)(b) baryon lifetimes
No full textUsing a data sample of pp collisions corresponding to an integrated luminosity of 3 fb−1, the Ξ−b and Ω−b baryons are reconstructed in the Ξ−b → J/ψΞ− and Ω−b → J/ψΩ− decay modes and their lifetimes measured to be
τ(Ξ−b) = 1.55+0.10−0.09 (stat) ± 0.03 (syst) ps,
τ(Ω−b) = 1.54+0.26−0.21 (stat) ± 0.05 (syst) ps.
These are the most precise determinations to date. Both measurements are in good agreement with previous experimental results and with theoretical predictions
Effective lifetime measurements in the B-s(0) -> K+K-, B-0 -> K+pi(-) and B-s(0) -> pi K-+(-) decays
No full textMeasurements of the effective lifetimes in the View the MathML source, B0→K+π− and View the MathML source decays are presented using 1.0 fb−1 of pp collision data collected at a centre-of-mass energy of 7 TeV by the LHCb experiment. The analysis uses a data-driven approach to correct for the decay time acceptance.
This is the most precise determination to date of the effective lifetime in the View the MathML source decay and provides constraints on contributions from physics beyond the Standard Model to the View the MathML source mixing phase and the width difference ΔΓs
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of the branching fraction
No full textThe B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
- …
