CRC (cyclic redundancy check)-aided decoding schemes are proposed to improve the performance of polar codes. A unified description of successive cancellation decoding and its improved version with ...list or stack is provided and the CRC-aided successive cancellation list/stack (CA-SCL/SCS) decoding schemes are proposed. Simulation results in binary-input additive white Gaussian noise channel (BI-AWGNC) show that CA-SCL/SCS can provide significant gain of 0.5 dB over the turbo codes used in 3GPP standard with code rate 1/2 and code length 1024 at the block error probability (BLER) of 10 -4 . Moreover, the time complexity of CA-SCS decoder is much lower than that of turbo decoder and can be close to that of successive cancellation (SC) decoder in the high SNR regime.
The regulation of type I and type II photosensitizers during the generation of reactive oxygen species (ROS) is a challenging issue in photooxidation reactions. In this study, a novel pyrene-based ...two-dimensional supramolecular organic framework (SOF) was constructed in water using the host-guest interactions between the methylated vinylpyridine arms of the pyrene derivative (Pmvp) and cucurbit8uril (CB8), in which the four methylated vinylpyridine arms can be encapsulated by the cavity of CB8 to form a stable framework structure with periodic pore structure and homogeneous solubility. More importantly, the construction of the SOF can realize the regulation of singlet oxygen (
1
O
2
) and superoxide anion radical (O
2
&z.rad;
−
) generation capacity in ROS production. Specifically, the
1
O
2
generation capacity decreases, while the O
2
&z.rad;
−
generation capacity increases, and the SOF exhibits high photocatalytic conversion efficiency in the photocatalysis of the aerobic oxidation of thioanisoles and the oxidative hydroxylation of arylboronic acids in water, with yields up to 87% and 99%, respectively. This study presents an approach based on the concept of SOFs for the effective management of ROS in photooxidation reactions.
We report herein a novel pyrene-based two-dimensional supramolecular organic framework (SOF) in water
via
host-guest interactions, which exhibits regulation of ROS and high photocatalytic efficiency.
Policosanol exhibits a lipid accumulation alleviating effect, but the underlying mechanisms remains unclear. Bile acids are a significant factor in regulating cholesterol and lipid metabolism ...homeostasis in mammals. This study was aimed to elucidate the alleviating effect and underlying mechanisms of policosanol on hepatic lipid accumulation through bile acid (BA) metabolism. Policosanol supplementation significantly reduced hepatic triglycerides (19.29%), cholesterol (30.38%) in high fat diet (HFD) induced obese mice (P < 0.05). Furthermore, compared with the control group, HFD decreased the levels of total BAs (TBAs, 37.67%) and cholic acid (CA, 62.74%) in the serum of mice (P < 0.05). Meanwhile, compared to HFD group, policosanol also increased the level of secondary BAs (SBAs) and muricholic acids (MCAs, P < 0.05). qRT‐PCR combined with protein level analysis revealed that policosanol significantly decreased sterol regulatory element‐binding protein (SREBP‐1c) and CD36, and increased the expression level of cytochrome P450 family 7 subfamily A member 1 (CYP7A1) and cytochrome P450 Family 27 Subfamily A Member 1 (CYP27A1, P < 0.05). Additionally, in the liver, policosanol was found downregulated the expression of farnesoid X receptor (FXR)‐small heterodimer partner (SHP), and activate the Takeda G‐coupled protein receptor 5 (TGR5)‐adenosine‐monophosphate‐activated protein kinase (APMK) signaling pathway (P < 0.05). Peroxisome proliferator activated receptor (PPAR)‐α, hormone sensitive lipase (HSL), and carnitine palmitoyltransferase (CPT)‐1α also significantly increased in HP group (P < 0.05). The aforementioned results reveal that the potential mechanism of policosanol in alleviating liver lipid accumulation is to promote BA synthesis and lipolysis through regulating the cross‐talk of the AMPK–FXR–TGR5. New insight for the application of policosanol as an anti‐fatty liver functional food ingredient or supplement is also provided.
Practical Application
Policosanol is an important active component of cereals and insect waxes (15–80%). However, almost no policosanol in refined foods such as clear corn germ oil and wheat flour. This study showed that oral administration of policosanol can significantly reduce triglyceride and cholesterol levels in the liver through affecting AMPK–TGR5–FXR cross‐talk, whereas no significant toxicological effect is reported in human and mouse models. This study may provide theoretical support for the theory of dietary structure and the development of dietary supplements to improve lipid metabolism targeting the “bile acid–AMPK–TGR5” pathway.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Carbon dots (CDs) are a type of carbon‐based luminescent material with a zero‐dimensional structure and a size of less than 10 nm, which are composed of sp2/sp3 hybrid carbon nuclei and surface ...functional groups. Because CDs has strong photoluminescence and good light absorption in the ultraviolet and near visible regions, it is an excellent candidate for photocatalytic applications. However, the use of nonmetallic doped CDs as photosensitizers for direct photocatalytic organic reactions has been limited to several scattered reports. Herein, we present nitrogen‐doped carbon dots (N‐CDs) that has a capability for not only produce reactive oxygen species (ROS), including superoxide anion radical (O2⋅−) and singlet oxygen (1O2), but also provide an unprecedented high activity of dehalogenative oxyalkylation of styrene with a yield of 93 %. This work develops a novel opportunity to utilize cost‐effective and easily accessible CDs for the advancement of photocatalysis.
We designed and fabricated nitrogen‐doped carbon dots (N‐CDs) by using citric acid and diethylenetriamine in a solvothermal method. N‐CDs has excellent ability to generate 1O2 and O2⋅− under irradiation and was further employed as photocatalysts to promote the high selectivity of dehalogenative oxyalkylation of styrene under the mediation of oxygen.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
As improved versions of the successive cancellation (SC) decoding algorithm, the successive cancellation list (SCL) decoding and the successive cancellation stack (SCS) decoding are used to improve ...the finite-length performance of polar codes. In this paper, unified descriptions of the SC, SCL, and SCS decoding algorithms are given as path search procedures on the code tree of polar codes. Combining the principles of SCL and SCS, a new decoding algorithm called the successive cancellation hybrid (SCH) is proposed. This proposed algorithm can provide a flexible configuration when the time and space complexities are limited. Furthermore, a pruning technique is also proposed to lower the complexity by reducing unnecessary path searching operations. Performance and complexity analysis based on simulations shows that under proper configurations, all the three improved successive cancellation (ISC) decoding algorithms can approach the performance of the maximum likelihood (ML) decoding but with acceptable complexity. With the help of the proposed pruning technique, the time and space complexities of ISC decoders can be significantly reduced and be made very close to those of the SC decoder in the high signal-to-noise ratio regime.
Due to the high C-H bond dissociation energy of alkanes, the utilization of alkanes as alkyl radical precursors for C-H functionalization of heteroarenes is synthetically captivating but practically ...challenging, especially under metal- and photocatalyst-free conditions. We report herein a mild and practical visible-light-mediated method for C-H alkylation of quinoxalin-2(1
H
)-ones using trifluoroacetic acid as a hydrogen atom transfer reagent and air as an oxidant. This mild protocol was performed under metal- and photocatalyst-free circumstances and presented good functional-group tolerance as well as a broad substrate scope.
Visible-light-mediated C-H alkylation of quinoxalin-2(1
H
)-ones using trifluoroacetic acid as a hydrogen atom transfer reagent under metal- and photocatalyst-free conditions is reported.
In this paper, pattern division multiple access (PDMA), which is a novel nonorthogonal multiple access scheme, is proposed for fifth-generation (5G) radio networks. The PDMA pattern defines the ...mapping of transmitted data to a resource group that can consist of time, frequency, and spatial resources or any combination of these resources. The pattern is introduced to differentiate signals of users sharing the same resources, and the pattern is designed with disparate diversity order and sparsity so that PDMA can take the advantage of the joint design of transmitter and receiver to improve system performance while maintaining detection complexity to a reasonable level. System level simulation results show that PDMA can support six times simultaneous connections than that of conventional and at least 30% improvement in spectrum efficiency over orthogonal frequency division multiple access.
The competitive nature of type II photosensitizers in the transfer of excitation energy for the generation of singlet oxygen (
1
O
2
) presents significant challenges in the design of type I ...photosensitizers to produce the superoxide anion radical (O
2
&z.rad;−
). In this study, we present an efficient method for the direct transformation of type II photosensitizers into type I photosensitizers through the implementation of an artificial light-harvesting system (ALHSs) involving a two-step sequential energy transfer process. The designed supramolecular complex (DNPY-SBE-β-CD) not only has the ability to generate
1
O
2
as type II photosensitizers, but also demonstrates remarkable fluorescence properties in aqueous solution, which renders it an efficient energy donor for the development of type I photosensitizers ALHSs, thereby enabling the efficient generation of O
2
&z.rad;−
. Meanwhile, to ascertain the capability and practicality of this method, two organic reactions were conducted, namely the photooxidation reaction of thioanisole and oxidative hydroxylation of arylboronic acids, both of which display a high level of efficiency and exhibit significant catalytic performance. This work provides an efficient method for turning type II photosensitizers into type I photosensitizers by a two-step sequential energy transfer procedure.
We present an efficient method for the transformation of type II photosensitizers (
1
O
2
) into type I photosensitizers (O
2
&z.rad;−
) through the implementation of an artificial light-harvesting system involving a two-step sequential energy transfer process.
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IJS, KILJ, NUK, UL, UM, UPUK
It is of great significance to improve the photocatalytic performance of photosensitizers by supramolecular strategies. In this study, we constructed a supramolecular cascade assembly ...(PATT-CB7-SBE-β-CD) comprising an
N
,
N
,
N
′,
N
′-tetra(
p
-aminophenyl)-
p
-phenylenediamine derivative (PATT), cucurbit7uril (CB7), and sulfobutylether-β-cyclodextrin (SBE-β-CD). Compared to PATT, the supramolecular cascade assembly exhibits a remarkable 30-fold enhancement in fluorescence emission intensity. The excellent fluorescence emission of PATT-CB7-SBE-β-CD makes it an optimal energy donor to construct a light-harvesting system (LHS) with Eosin Y (EY) and sulforhodamine 101 (SR101) through a sequential two-step energy transfer process. The PATT-CB7-SBE-β-CD+EY+SR101 served as a photosensitizer to facilitate the photocatalytic oxidation of
N
-phenyltetrahydroisoquinoline and its derivatives. Compared to PATT-CB7-SBE-β-CD and PATT-CB7-SBE-β-CD+EY, PATT-CB7-SBE-β-CD+EY+SR101 exhibits significantly enhanced photocatalytic performance, which is achieved by enhancing the generation efficiency of the superoxide anion radical (O
2
&z.rad;
−
) through sequential two-step energy transfer processes. The finding of this study demonstrated that the generation of O
2
&z.rad;
−
can be greatly enhanced through effective energy transfer to improve the photocatalytic performance.
A supramolecular cascade assembly PATT-CB7-SBE-β-CD was constructed, which not only exhibited remarkable fluorescence enhancement, but also can be used as an excellent energy donor in a sequential energy transfer process for photocatalysis.
An artificial light-harvesting system (ALHS) was developed in aqueous solution by employing the electrostatic co-assembly of a tetraphenylethylene derivative modified with two sulfonate groups ...(TPE-BSBO) and hyperbranched polyethyleneimine (PEI) as the energy donors, and 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (DBT) as the energy acceptors. The ALHS exhibits not only high efficiency in energy transfer and conversion but also a significant enhancement in the generation of reactive oxygen species (ROS), especially superoxide anion radicals (O
2
&z.rad;
−
), facilitating its utilization in photocatalytic oxidation reactions.
An artificial light-harvesting system was developed by employing the electrostatic co-assembly of TPE-BSBO and PEI, which can be used as photocatalysts for photocatalytic oxidation reactions.
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