In this paper, we consider a three-dimensional chemotaxis-Stokes system
0.1
n
t
+
u
·
∇
n
=
Δ
n
m
-
∇
·
(
n
S
(
x
,
n
,
c
)
·
∇
c
)
,
x
∈
Ω
,
t
>
0
,
c
t
+
u
·
∇
c
=
Δ
c
-
n
f
(
c
)
,
x
∈
Ω
,
t
>
0
,
...u
t
+
∇
P
=
Δ
u
+
n
∇
ϕ
,
x
∈
Ω
,
t
>
0
,
∇
·
u
=
0
,
x
∈
Ω
,
t
>
0
,
(
∇
n
m
-
n
S
(
x
,
n
,
c
)
·
∇
c
)
·
ν
=
∂
c
∂
ν
=
0
,
u
=
0
,
x
∈
∂
Ω
,
t
>
0
,
n
(
x
,
0
)
=
n
0
(
x
)
,
c
(
x
,
0
)
=
c
0
(
x
)
,
u
(
x
,
0
)
=
u
0
(
x
)
,
x
∈
Ω
in a bounded domain
Ω
⊂
R
3
with smooth boundary, where
ϕ
,
f
and
S
are given functions with values in
Ω
,
0
,
∞
)
and
R
3
×
3
, respectively, under the no-flux boundary condition for
n
,
c
and Dirichlet boundary condition for
u
. It is also required that
f
∈
C
1
(
0
,
∞
)
)
is locally bounded in
0
,
∞
)
, that
S
satisfies
|
S
(
x
,
n
,
c
)
|
≤
n
l
-
2
S
0
(
c
)
with some nondecreasing
S
0
:
0
,
∞
)
→
0
,
∞
)
, and that
m
fulfills
0.2
m
>
5
3
l
-
20
9
and
m
>
-
3
4
l
+
21
8
with
25
12
≥
l
>
2
.
Then, with any reasonably regular initial data, the corresponding initial-boundary problem for (0.1) processes a global in time and bounded solution. This result extends the previous global boundedness result with
m
>
m
∗
(
l
)
, where
m
∗
(
l
)
=
l
-
5
6
,
if
31
12
≥
l
>
2
,
7
5
l
-
28
15
,
if
l
>
31
12
,
(
15
) since both
l
-
5
6
≥
5
3
l
-
20
9
and
l
-
5
6
≥
-
3
4
l
+
21
8
hold on
25
12
≥
l
>
2
.
We consider an incompressible chemotaxis-Navier-Stokes system with nonlinear diffusion and rotational flux
n
t
+
u
·
∇
n
=
Δ
n
m
-
∇
·
(
n
S
(
x
,
n
,
c
)
·
∇
c
)
,
x
∈
Ω
,
t
>
0
,
c
t
+
u
·
∇
c
=
Δ
...c
-
n
c
,
x
∈
Ω
,
t
>
0
,
u
t
+
κ
(
u
·
∇
)
u
+
∇
P
=
Δ
u
+
n
∇
ϕ
,
x
∈
Ω
,
t
>
0
,
∇
·
u
=
0
,
x
∈
Ω
,
t
>
0
in a bounded domain
Ω
⊂
R
N
(
N
=
2
,
3
)
with smooth boundary
∂
Ω
, where
κ
∈
R
. The chemotaxtic sensitivity
S
is a given tensor-valued function fulfilling
|
S
(
x
,
n
,
c
)
|
≤
S
0
(
c
)
for all
(
x
,
n
,
c
)
∈
Ω
¯
×
0
,
∞
)
×
0
,
∞
)
with
S
0
(
c
)
nondecreasing on
0
,
∞
)
. By introducing some new methods (see Sect.
4
and Sect.
5
), we prove that under the condition
m
>
1
and some other proper regularity hypotheses on initial data, the corresponding initial-boundary problem possesses at least one global weak solution. The present work also shows that the weak solution could be bounded provided that
N
=
2
. Since
S
is tensor-valued, it is easy to see that the restriction on
m
here is optimal, which answers the left question in Bellomo-Belloquid-Tao-Winkler (Math Models Methods Appl Sci 25:1663–1763, 2015) and Tao-Winkler (Ann Inst H Poincaré Anal Non Linéaire 30:157–178, 2013). And obviously, this work improves previous results of several other authors (see Remark 1.1).
With the development of power electronics technology and the increasing DC sensitive load, DC microgrid is an important direction for future power distribution. At present, there are few studies on ...the power quality of DC microgrids. This paper introduces a DC voltage harmonic and interharmonic detection method suitable for DC microgrid. The voltage of the DC microgrid is divided into DC voltage and harmonics and interharmonics, and they are studied separately. For the DC voltage, use the regression equation to represent and restore it. For harmonics and interharmonics, the method of windowed Fourier transform is used for analysis, and the quadratic interpolation method is used for correction.Through simulation, the detection and reduction of DC voltage harmonics and interharmonics under various operating conditions are analyzed. Finally, the feasibility and accuracy of this algorithm are verified.
In this paper, we consider a chemotaxis-Navier-Stokes ...system(0.1){nt+u⋅∇n=Δnm−∇⋅(nS(x,n,c)⋅∇c),x∈Ω,t>0,ct+u⋅∇c=Δc−nc,x∈Ω,t>0,ut+κ(u⋅∇)u+∇P=Δu+n∇ϕ,x∈Ω,t>0,∇⋅u=0,x∈Ω,t>0,(∇nm−nS(x,n,c)⋅∇c)⋅ν=∂νc=0,u=0,x∈∂Ω,t>0,n(x,0)=n0(x),c(x,0)=c0(x),u(x,0)=u0(x),x∈Ω, in a bounded domain Ω⊂RN(N=2,3) with smooth boundary, where κ∈R and the sensitivity S is a tensor-valued function satisfying |S(x,n,c)|≤(n+1)−αS0(c) with some nondecreasing S0(c). Applying some new methods (Section 3), we achieve to improve the restriction from m+α>109 (39) to m+α>1. Our results also show that system (0.1) possesses at least one global bounded weak solution in the case N=2.
Stroke is a leading cause of death, with a continuously increasing incidence. As a metabolic process that catabolizes glucose pyruvate and provides adenosine triphosphate (ATP), glycolysis plays a ...crucial role in different diseases. Phosphoglycerate kinase 1 (PGK1) facilitates energy production with biosynthesis in many diseases, including stroke. However, the exact role of PGK1/glycolysis in stroke remains to be elucidated. A rat model of middle cerebral artery occlusion (MCAO) was used to mimic ischemia/reperfusion injuries. Oxygen glucose deprivation/re-oxygenation (OGD/R) was used to induce injury to highly aggressively proliferating immortalized (HAPI) rat microglial cells. The extracellular acidification rate (ECAR) was determined using an XFe24 Extracellular Flux Analyzer. ATP, lactate dehydrogenase, tumor necrosis factor-alpha, and interleukin-6 levels were measured using commercial kits. Chromatin immunoprecipitation assay was performed to examine the interaction between H3K27ac or p300 and the PGK1 promoter region. PGK1 was either knocked down or overexpressed by lentivirus. Thus, to examine its role in stroke, real-time polymerase chain reaction and immunoblotting were used to measure gene expression. The expression of PGK1 was increased and associated with M1 polarization and glycolysis in MCAO rat models. OGD/R promoted M1 polarization and HAPI microglial cell inflammation by regulating glycolysis. Silencing PGK1 reduced OGD/R-increased M1 polarization, inflammation, and glycolysis. Conversely, the overexpression of PGK1 promoted HAPI microglial cell inflammation by regulating glycolysis. The mechanism showed that histone acetyltransferase p300 promoted PGK1 expression through H3K27 acetylation. Finally, data indicated that silencing PGK1 inhibited microglia M1 polarization, inflammation, and glycolysis in MCAO rat models. PGK1 could promote ischemia/reperfusion injury-induced microglial M1 polarization and inflammation by regulating glycolysis, which might provide a novel direction in developing new therapeutic medications for preventing or treating stroke.
•The Atlas stent shows promise as a safe and effective treatment option for intracranial stenosis.•The use of the Gateway catheter to deliver the stent appears to be associated with a lower risk of ...post-procedural stroke compared to using the microcatheter.•The incidence of in-stent restenosis may be influenced by the degree of residual stenosis.
This study aimed to compare the safety and efficacy of the Atlas stent released by the Gateway catheter and microcatheter in the treatment of intracranial stenosis (IS).
The primary efficacy and safety outcomes were the in-stent restenosis (ISR) rate and post-procedural stroke or death within one month.
Atlas stents were deployed using the Gateway catheter and microcatheter in 19 (57.6 %) and 14 (42.4 %) procedures, respectively. Follow-up imaging data were available for 26 patients; the incidence of ISR was 15.4 %, and the ISR rate was higher, though not significantly, in the microcatheter group than in the Gateway group (30.0% vs. 6.25 %, P = .39). Clinical follow-up data were available for 30 patients; the post-procedural stroke rate was 3.3 % within one month and 13.3 % from one month to one year. The post-procedural stroke rate within one month was higher, though not significantly, in the microcatheter group than in the Gateway group (7.7% vs. 0 %, P = .43). The Gateway group had a significantly lower rate of post-procedural stroke in the same territory than that of the microcatheter group (0% vs. 30.8 %, P = .026). A higher incidence of residual stenosis <30 % was found in the non-ISR group than in the ISR group (72.2% vs. 0 %, P = .014).
This study provides preliminary evidence that the Atlas stent is safe and effective for IS treatment. The use of the Gateway catheter to deliver the Atlas stent appears to be safer than using microcatheter. The incidence of ISR may be related to the degree of the residual stenosis.
There is an increasing number of studies on the transradial approach (TRA) for carotid artery stenting. We aimed to summarize the published data on TRA vs the transfemoral approach (TFA). We searched ...Science Direct, Embase, PubMed, and Web of Science databases for the relevant literature. Primary outcomes included surgical success and cardiovascular and cerebrovascular complication rates; secondary outcomes included the rates of vascular access-related and other complications. We also compared the crossover rate, success rate, and complications between TRA and TFA carotid stenting. This is the first such meta-analysis regarding TRA and TFA. Twenty studies on TRA carotid stenting were included (n = 1300). Among 19 studies, the success rate of TRA carotid stenting was .951 (95% confidence interval CI: .926–.975); death rate was .022 (.011–.032); stroke rate was .005 (.001–.008); radial artery occlusion rate was .008 (.003–.013); and forearm hematoma rate was .003 (−.000 to .006). Among 4 studies comparing TRA and TFA, the success rate was lower (odds ratio: .02; 95% CI: .00–.23) and crossover rate was higher (odds ratio: 40.16; 95% CI: 4.41–365.73) with TRA. Thus, transradial neuro-interventional surgery has a lower success rate than TFA.
This study aims to share our experience with the arm-only combined transarterial and transvenous access approach for neurointerventional procedures and evaluate its efficacy and safety.
The arm-only ...combined transarterial and transvenous access approach was performed using the right/bilateral proximal radial arteries and the right forearm superficial vein system, guided by ultrasonic guidance. Arterial access closure was achieved using a transradial band radial compression device, while manual compression was utilized for venous approach closure.
Thirteen procedures were successfully performed using the arm-only combined transarterial and transvenous access approach, yielding favorable outcomes. The procedures included dural arteriovenous fistula embolization (seven cases), cerebral arteriovenous malformation embolization (four cases), venous sinus thrombosis catheter-directed thrombolysis and intravenous thrombectomy (one case), and cerebral venous sinus stenosis manometry (one case). All procedures were uneventful, allowing patients to ambulate on the same day. At discharge, all patients exhibited modified Rankin scores of 0-2, without any access site or perioperative complications.
This double-center study preliminarily demonstrates the feasibility and safety of arm-only combined transarterial and transvenous access applied in neurointerventional procedures for complicated cerebrovascular diseases. The proximal radial artery and forearm superficial vein are recommended as the primary access sites. Unobstructed compression is strongly recommended for radial approach closure.
This study aimed to add evidence and experience on the arm-only combined transarterial and transvenous access, as a new approach, for neurointerventional treatment that required arteriovenous approaches.
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