SU(3) symmetry breaking in charmed baryon decays Geng, C. Q.; Hsiao, Y. K.; Liu, Chia-Wei ...
European physical journal. C, Particles and fields,
07/2018, Letnik:
78, Številka:
7
Journal Article
Recenzirano
Odprti dostop
We explore the breaking effects of the
SU
(3) flavor symmetry in the singly Cabibbo-suppressed anti-triplet charmed baryon decays of
B
c
→
B
n
M
, with
B
c
=
(
Ξ
c
0
,
Ξ
c
+
,
Λ
c
+
)
and
B
n
(
M
)
...the baryon (pseudo-scalar) octets. We find that these breaking effects can be used to account for the experimental data on the decay branching ratios of
B
(
Λ
c
+
→
Σ
0
K
+
,
Λ
0
K
+
)
and
R
K
/
π
′
=
B
(
Ξ
c
0
→
Ξ
-
K
+
)
/
B
(
Ξ
c
0
→
Ξ
-
π
+
)
. In addition, we obtain that
B
(
Ξ
c
0
→
Ξ
-
K
+
,
Σ
-
π
+
)
=
(
4.6
±
1.7
,
12.8
±
3.1
)
×
10
-
4
,
B
(
Ξ
c
0
→
p
K
-
,
Σ
+
π
-
)
=
(
3.0
±
1.0
,
5.2
±
1.6
)
×
10
-
4
and
B
(
Ξ
c
+
→
Σ
0
(
+
)
π
+
(
0
)
)
=
(
10.3
±
1.7
)
×
10
-
4
, which all receive significant contributions from the breaking effects, and can be tested by the BESIII and LHCb experiments.
The observation of CP violation has been experimentally verified in numerous
B
decays but is yet to be confirmed in final states with half-spin particles. We focus our attention on baryonic
B
-meson ...decays mediated dominantly through internal
W
-emission processes and show that they are promising processes to observe for the first time the CP violating effects in
B
decays to final states with half-spin particles. Specifically, we study the
B
¯
0
→
p
p
¯
π
0
(
ρ
0
)
and
B
¯
0
→
p
p
¯
π
+
π
-
decays. We obtain
B
(
B
¯
0
→
p
p
¯
π
0
)
=
(
5.0
±
2.1
)
×
10
-
7
, in agreement with current data, and
B
(
B
¯
0
→
p
p
¯
ρ
0
)
≃
B
(
B
¯
0
→
p
p
¯
π
0
)
/
3
. Furthermore, we find
A
CP
(
B
¯
0
→
p
p
¯
π
0
,
p
p
¯
ρ
0
,
p
p
¯
π
+
π
-
)
=
(
-
16.8
±
5.4
,
-
12.6
±
3.0
,
-
11.4
±
1.9
)
%
. With measured branching fractions
B
(
B
¯
0
→
p
p
¯
π
0
,
p
p
¯
π
+
π
-
)
∼
O
(
10
-
6
)
, we point out that
A
CP
∼
-
(
10
-
20
)
%
can be new observables for CP violation, accessible to the Belle II and/or LHCb experiments.
A
bstract
For the two-body
B
c
→
B
M
decays, where
B
c
denotes the anti-triplet charm baryon and
B
(
M
) the octet baryon (meson), there exist two theoretical studies based on the SU(3) flavor SU(3)
...f
symmetry. One is the irreducible SU(3)
f
approach (IRA). In the irreducible SU(3)
f
representation, the effective Hamiltonian related to the initial and final states forms the amplitudes for
B
c
→
B
M
. The other is the topological-diagram approach (TDA), where the
W
-boson emission and
W
-boson exchange topologies are drawn and parameterized for the decays. As required by the group theoretical consideration, we present the same number of the IRA and TDA amplitudes. We can hence relate the two kinds of the amplitudes, and demonstrate the equivalence of the two SU(3)
f
approaches. We find a specific
W
-boson exchange topology only contributing to
Ξ
c
0
→
B
M
. Denoted by
E
M
, it plays a key role in explaining
B
(
Ξ
c
0
→
Λ
0
K
S
0
,
Σ
0
K
S
0
,
Σ
+
K
−
). We consider that
Λ
c
+
→ nπ
+
and
Λ
c
+
→ pπ
0
proceed through the constructive and destructive interfering effects, respectively, which leads to
B
(
Λ
c
+
→ nπ
+
) »
B
(
Λ
c
+
→ pπ
0
) in agreement with the data. With the exact and broken SU(3)
f
symmetries, we predict the branching fractions of
B
c
→
B
M
to be tested by future measurements.
A
bstract
We study the semileptonic and non-leptonic charmed baryon decays with SU(3) flavor symmetry, where the charmed baryons can be
B
c
= (Ξ
c
0
, Ξ
c
+
, Λ
c
+
),
B
c
′
= (
Σ
c
(++,+,0)
, Ξ
c
...′ (+,0)
, Ω
c
0
),
B
cc
= (Ξ
cc
+ +
, Ξ
cc
+
, Ω
c
+
) or
B
cc
= Ω
ccc
+ +
. With
B
n
(′)
denoted as the baryon octet (decuplet), we find that the
B
c
→
B
n
′
ℓ
+
ν
ℓ
decays are forbidden, while the Ω
c
0
→ Ω
−
ℓ
+
ν
ℓ
, Ω
cc
+
→ Ω
c
0
ℓ
+
ν
ℓ
, and Ω
ccc
+ +
→ Ω
cc
+
ℓ
+
ν
ℓ
decays are the only existing Cabibbo- allowed modes for
B
c
′
→
B
n
′
ℓ
+
ν
ℓ
,
B
cc
→
B
c
′
ℓ
+
ν
ℓ
, and
B
ccc
→
B
cc
(′)
ℓ
+
ν
ℓ
, respectively. We predict the rarely studied
B
c
→
B
n
(′)
M
decays, such as
ℬ
Ξ
c
0
→
Λ
0
K
¯
0
,
Ξ
c
+
→
Ξ
0
π
+
=
8.3
±
0.9
,
8.0
±
4.1
×
10
−
3
and
ℬ
Λ
c
+
→
Δ
+
+
π
−
,
Ξ
c
0
→
Ω
−
K
+
=
5.5
±
1.3
,
4.8
±
0.5
×
10
−
3
. For the observation, the doubly and triply charmed baryon decays of
Ω
cc
+
→
Ξ
c
+
K
¯
0
,
Ξ
cc
+
+
→
Ξ
c
+
π
+
,
Σ
c
+
+
K
¯
0
,
and
Ω
c
c
c
+
+
→
Ξ
cc
+
+
K
¯
0
,
Ω
cc
+
π
+
,
Ξ
c
+
D
+
are the favored Cabibbo-allowed decays, which are accessible to the BESIII and LHCb experiments.
In the quark-diagram scheme, we study the charmed baryon decays of
B
c
→
B
∗
M
, where
B
c
is
Λ
c
+
or
Ξ
c
+
(
0
)
, together with
B
∗
(
M
) the decuplet baryon (pseudoscalar meson). It is found that ...only two
W
-exchange processes are allowed to contribute to
B
c
→
B
∗
M
. Particularly, we predict
B
(
Λ
c
+
→
Σ
∗
0
(
+
)
π
+
(
0
)
)
=
(
2.8
±
0.4
)
×
10
-
3
, which respects the isospin symmetry. Besides, we take into account the
SU
(3) flavor symmetry breaking, in order to explain the observation of
B
(
Λ
c
+
→
Σ
∗
+
η
)
. For the decays involving
Δ
+
+
(
u
u
u
)
, we predict
B
(
Λ
c
+
→
Δ
+
+
π
-
,
Ξ
c
+
→
Δ
+
+
K
-
)
=
(
7.0
±
1.4
,
13.5
±
2.7
)
×
10
-
4
as the largest branching fractions in the singly Cabibbo-suppressed
Λ
c
+
,
Ξ
c
+
→
B
∗
M
decay channels, respectively, which are accessible to the LHCb, BELLEII and BESIII experiments.
The present work utilizes electrospinning to fabricate synthetic polymer/DNA composite scaffolds for therapeutic application in gene delivery for tissue engineering. The scaffolds are non-woven, ...nano-fibered, membranous structures composed predominantly of poly(lactide-co-glycolide) (PLGA) random copolymer and a poly(
d,
l-lactide)–poly(ethylene glycol) (PLA–PEG) block copolymer. Release of plasmid DNA from the scaffolds was sustained over a 20-day study period, with maximum release occurring at ∼2 h. Cumulative release profiles indicated amounts released were approximately 68–80% of the initially loaded DNA. Variations in the PLGA to PLA–PEG block copolymer ratio vastly affected the overall structural morphology, as well as both the rate and efficiency of DNA release. Results indicated that DNA released directly from these electrospun scaffolds was indeed intact, capable of cellular transfection, and successfully encoded the protein β-galactosidase. When tested under tensile loads, the electrospun polymer/DNA composite scaffolds exhibited tensile moduli of ∼35 MPa, with ∼45% strain initially. These values approximate those of skin and cartilage. Taken together, this work represents the first successful demonstration of plasmid DNA incorporation into a polymer scaffold using electrospinning.
A
bstract
We study the two-body anti-triplet charmed baryon decays based on the diagrammatic approach with SU(3) flavor symmetry. We extract the two
W
-exchange effects as
E
B
and
E'
that contribute ...to the
Λ
c
+
→
Ξ
0
K
+
decay, together with the relative phases, where
E
B
gives the main contribution. Besides, we find that
B
Λ
c
+
→
p
π
0
=
0.8
−
0.8
+
0.9
×
10
−
4
,which is within the experimental upper bound. Particularly, we obtain
B
Ξ
c
+
→
Ξ
0
π
+
=
9.3
±
3.6
×
10
−
3
,
B
Ξ
c
0
→
Ξ
−
π
+
Λ
0
K
¯
0
=
19.3
±
2.8
8.3
±
5.0
×
10
−
2
and
B
Ξ
c
0
→
Ξ
−
K
+
=
5.6
±
0.8
×
10
−
4
, which all agree with the data. For the singly Cabibbo suppressed
Λ
c
+
decays, we predict that
B
Λ
c
+
→
n
π
+
pη
'
Σ
+
K
0
=
7.7
±
2.0
7.1
±
1.4
19.1
±
4.8
×
10
−
4
, which are accessible to the experiments at BESIII, BELLEII and LHCb.
The aim of this study was to investigate potential biomarkers in human saliva and plasma to aid in the early diagnosis of oral squamous cell carcinoma (OSCC). Saliva and plasma samples obtained from ...OSCC patients (n=41) and non-oral cancer patients (n=24) were analyzed by Luminex Bead-based Multiplex Assay. Data were analyzed using the non-parametric Mann–Whitney U-test, Kruskal–Wallis test, and receiver operating characteristics curve (ROC) to evaluate the predictive power of 14 biomarkers individually for OSCC diagnosis. The plasma level of IP-10 in early OSCC differed significantly from that in controls. Among the salivary biomarkers, IL-1β, IL-6, IL-8, MIP-1β, eotaxin and IFN-γ and TNF-α showed significant differences between OSCC patients and controls. With respect to carcinogenesis, significant differences in plasma levels of eotaxin, G-CSF, and IL-6 were found between OSCC stages III/IV and OSCC stages I/II. The area under the curve (AUC) for OSCC vs. control was greater than 0.7 for plasma IP-10 and saliva IL-1β, IL-6, IL-8, and TNF-α. The study findings indicate that salivary biomarkers may serve a useful role as a complementary adjunct for the early detection of oral OSCC. With regard to the evaluation of tumour progression, plasma eotaxin, G-CSF, and IL-6 may help in the detection of advanced OSCC. However, the correlation between saliva and plasma biomarkers in OSCC was weak.
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