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.
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.
Background and aims
The function of interleukin (IL)‐10‐producing B cells (B10 cell) is compromised in patients with allergic diseases. Protease‐activated receptor (PAR)‐2 has immunoregulatory ...functions. This study aimed to elucidate the role of PAR2 in the suppression of IL‐10 expression in peripheral B cells.
Methods
Peripheral blood B cells were collected from patients with allergic rhinitis (AR). A correlation between the expression of Bcl2‐like protein 12 (Bcl2L12) and IL‐10 in the B cells was analyzed. An AR mouse model was developed.
Results
We observed that the expression of IL‐10 was lower in the peripheral B cells from patients with airway allergy. A negative correlation was identified between the expression of IL‐10 and PAR2 in B cells. Activation of PAR2 of B cells increased the expression of Bcl2L12 and suppression of LPS‐induced IL‐10 expression, which were inhibited by knocking down the Bcl2L12 gene. Treating B cells from AR patients with Bcl2L12‐shRNA‐carrying liposomes reversed the capability of IL‐10 expression and the immunosuppressive function. Administration of Bcl2L12 shRNA‐carrying liposomes attenuated experimental AR in mice.
Conclusions
Activation of PAR2 inhibits the expression of IL‐10 in B cells, which can be reversed by treating B cells with Bcl2L12 shRNA‐carrying liposomes. The data suggest that regulation of Bcl2L12 may be a novel approach in the treatment for AR.
Background
Chronic sinusitis (CRS) is a common otorhinolaryngologic disease that is frequently encountered in everyday practice, but there is a lack of precise data regarding the prevalence of CRS in ...developing countries. We performed a national investigation in China to determine the prevalence and associated factors of CRS.
Methods
We conducted a cross‐sectional investigation in 2012. A stratified four‐stage sampling method was used to select participants randomly from seven cities in mainland China. All participants were interviewed face‐to‐face via a standardized questionnaire. Unconditional logistic regression analyses were conducted to examine the association between smoking and sinusitis after adjusting for socio‐demographic factors.
Results
This study included a total of 10 636 respondents from seven cities. The overall prevalence of CRS was 8.0% and ranged from 4.8% to 9.7% in seven centres. Chronic sinusitis affected approximately 107 million people in mainland China. Chronic sinusitis was particularly prevalent among people with specific medical conditions, including allergic rhinitis, asthma, chronic obstructive pulmonary disease and gout. The prevalence was slightly higher among males (8.79%) than females (7.28%) (P = 0.004), and the prevalence varied by age group, ethnicity and marital status and education (P < 0.05), but not by household per capita income or living space (P > 0.05). Both second‐hand tobacco smoke and active smoking were independent risk factors for CRS (P = 0.001).
Conclusions
Chronic sinusitis is an important public health problem in China. Our study provides important information for the assessment of the economic burden of CRS and the development and promotion of public health policies associated with CRS particularly in developing countries.
Dynamic wireless charging (DWC) technology can help alleviate the problem of short driving range for battery-powered vehicles. In this article, a model predictive control (MPC) is applied to the buck ...converter on the secondary side of a DWC system to address fast output fluctuations. This approach features a fast-dynamic response, and no communication link is required. To solve the key issue of MPC, which is the computational burden, a polynomial fitting method based on the parsing solution of the sampled-data model is proposed. The complex matrix exponential calculation is replaced by simple polynomial operations, and the optimal duty cycle can be calculated directly by solving a quadratic function. This significantly reduces the computational burden. A DWC experimental setup is constructed, and results show that the proposed MPC has a better dynamic performance compared to proportional-integral control. The adjustment time is only 140 μs (around seven switching cycles) when the reference voltage is stepping. Moreover, the computational burden for matrix calculation in two-step prediction can be reduced by 50.6% and 79.7% compared to the lookup table and Taylor series approximation, respectively. Meanwhile, MPC with current limitation is analyzed and demonstrates a neat spectrum, small ripple but large response time.
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