Energy-Efficient Resource Allocation for OFDM-Based Cognitive Radio Networks with Imperfect Spectrum Sensing

Shuang Liang,Shouyi Yang,Wanming Hao,Bing Ning 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.3

In this study, energy-efficient (EE) resource allocation in orthogonal frequency division multiplexing-based cognitive radio networks with imperfect spectrum sensing is investigated. We present a new EE model by considering the sensing errors. Optimizing such an EE expression saves valuable resources, such as battery life, by selectively allocating power to underutilized subcarriers, and also achieves EE gain compared with general EE expression. Given that the primary user’s interference tolerance can be defined as either the Peak Interference Power (PIP) constraint or Average Interference Power (AIP) constraint for all subchannels, we compare the EE performance for the two interference power constraints. Finally, we propose an optimal EE resource allocation scheme based on the quasiconcave relation between the EE and transmit power. Simulations show that the new EE design improves EE compared with the conventional EE design, and the EE is higher with AIP constraint than that with PIP constrain under certain interference power.

Multiplex 권선을 통한 전동기의 토크 향상 및 토크 리플 개선

유상(Shuang Liu),왕녕(Ning Wang),윤명환(Myung-Hwan Yoon),홍정표(Jung-Pyo Hong) 대한전기학회 2015 대한전기학회 학술대회 논문집 Vol.2015 No.7

SERS study of Ag/FeS/4-MBA interface based on the SPR effect

Ma, Ning,Zhang, Xin-Yuan,Fan, Wenyue,Guo, Shuang,Zhang, Yongjun,Liu, Yang,Chen, Lei,Jung, Young Mee Elsevier 2019 Spectrochimica acta. Part A, Molecular and biomole Vol.219 No.-

<P><B>Abstract</B></P> <P>In this work, an ordered metal-semiconductor molecular system was introduced, and 4-mercaptobenzoic acid (4-MBA) was employed to study the charge transfer (CT) at the metal-semiconductor interface based on surface-enhanced Raman scattering (SERS) spectra. The thickness of the sputtered FeS was controlled so that the surface plasmon resonance (SPR) of Ag underwent a displacement change, and the contribution of the SPR to the CT was studied through surface plasmon (SP) absorption. Furthermore, SERS spectra obtained at different excitation wavelengths were used to calculate the degree of CT in the layer-by-layer sputtering system. When Ag was irradiated with incident light, the strong SPR of Ag was excited, generating an increased electromagnetic field (EM). This amplified EM generated hot electrons at the interface between the FeS and Ag, and then the hot electrons were rearranged. Therefore, we established a simple and effective method for studying the impact of SPR on interfacial CT and analyzed the SERS spectra in accordance with Lombardi's basic theory and the physical effects associated with SPR. This theory is in good agreement with the experimental results. On this basis, we also proposed a mechanism by which SPR impacts the CT, which is beneficial for studying interfacial CT and obtaining an in-depth understanding of the CT mechanism in SERS. This work also enables the expansion of the applications of the SERS technique in the field of nanomaterials.</P> <P><B>Highlights</B></P> <P> <UL> <LI> SERS substrate was designed based on the layer-by-layer sputtering of Ag/FeS. </LI> <LI> 4-MBA was employed to study the CT at the metal-semiconductor interface. </LI> <LI> The SPR of Ag promotes the electron transfer process of the Ag/FeS/4-MBA system. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>In this paper, we designed a layer-by-layer sputtering of Ag and FeS on the PS template. FeS, as an ultranarrow bandgap semiconductor with a bandgap width of only 0.1 eV, exhibited different properties for SERS. The SPR of Ag can be tuned by controlling the FeS film thickness, which is beneficial for studying interface CT and obtaining an in-depth understanding of the CT mechanism in SERS.</P> <P>[DISPLAY OMISSION]</P>

Gentic overexpression increases production of hypocrellin A in Shiraia bambusicola S4201

Dan Li,Ning Zhao,Bing-Jing Guo,Xi Lin,Shuang-Lin Chen,Shu-Zhen Yan 한국미생물학회 2019 The journal of microbiology Vol.57 No.2

Hypocrellin A (HA) is a perylenequinone (PQ) isolated from Shiraia bambusicola that shows antiviral and antitumor activities, but its application is limited by the low production from wild fruiting body. A gene overexpressing method was expected to augment the production rate of HA in S. bambusicola. However, the application of this molecular biology technology in S. bambusicola was impeded by a low genetic transformation efficiency and little genomic information. To enhance the plasmid transformant ratio, the Polyethylene Glycol-mediated transformation system was established and optimized. The following green fluorescent protein (GFP) analysis showed that the gene fusion expression system we constructed with a GAPDH promoter Pgpd1 and a rapid 2A peptide was successfully expressed in the S. bambusicola S4201 strain. We successfully obtained the HA high-producing strains by overexpressing O-methyltransferase/FAD-dependent monooxygenase gene (mono) and the hydroxylase gene (hyd), which were the essential genes involved in our putative HA biosynthetic pathway. The overexpression of these two genes increased the production of HA by about 200% and 100%, respectively. In general, this study will provide a basis to identify the genes involved in the hypocrellin A biosynthesis. This improved transformation method can also be used in genetic transformation studies of other fungi.

Optimizing bioconversion of ferulic acid to vanillin by Bacillus subtilis in the stirred packed reactor using Box-Behnken design and desirability function

Peng Chen,Lei Yan,Shuang Zhang,Zhengrong Wu,Suyue Li,Xiaojuan Yan,Ningbo Wang,Ning Liang,Hong Yu Li 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.1

A stirring bioreactor packed with a carbon fiber textiles (FT) biofilm formed by Bacillus subtilis was used to produce vanillin from ferulic acid. Biofilm formation was characterized by scanning electron microscopy. The interactive effects of three variables on vanillin molar yield (M) and conversion efficiency of ferulic acid (E) were evaluated by response surface methodology (RSM) with a Box-Behnken design (BBD). The optimal conversion conditions with a maximum overall desirability D of 0.983 were obtained by a desirability function. Considering the actual operation, the confirmation tests were performed using the slightly modified optimal conditions (initial ferulic acid concentration 1.55 g/ L, temperature 35oC, stirring speed 220 rpm). The results showed that M and E were 57.42 and 93.53%, respectively. This was only 1.03% and 1.87%, respectively, different from the predicted values, confirming the validity of the predicted models. These revealed that the stirred packed reactor could be successfully used in vanillin bioconversion from ferulic acid.

Tissue-specific expression of the NOD-like receptor protein 3 in BALB/c mice

Zhiqiang Huang,Meng Yu,Shuang Tong,Kun Jia,Rongchang Liu,Heng Wang,Shou-Jun Li,Zhang-Yong Ning 대한수의학회 2014 Journal of Veterinary Science Vol.15 No.2

Activation of the innate immune system requires recognitionof pathogen-associated molecular patterns, such as NOD-likereceptors. The NOD-like receptor protein 3 (NLRP3)inflammasome is involved in induction of the proinflammatorycytokine, IL-1β, and subsequent inflammatoryresponses. NLRP3 inflammasome plays important roles in theinflammatory and innate immune responses associated withautoimmune/inflammatory syndrome. However, analysis of thetissue distribution and expression profiles in BALB/c mice is stillincomplete. In this study, we investigated the tissue distributionand expression pattern of NLRP3 in BALB/c mice to furtherelucidate its function in innate immunity in this commonly usedlaboratory animal model. NLRP3 mRNA expression levels andtissue distribution of the protein were investigated by real-timequantitative PCR and immunohistochemical analyses,respectively. NLRP3 mRNA expression was higher in thekidney and inguinal lymph nodes than in other tissues. Cytoplasmic expression of NLRP3 was detected in the epithelialreticular cells of the spleen and thymus, lymphocytes in theinguinal lymph nodes, cardiac muscle cells, cerebral cortexneurons, alveolar macrophages, renal tubule cells and liversinusoidal endothelial cells. The results of this study will assistinvestigators in interpreting site-specific functions and roles ofNLRP3 in inflammatory responses.

Vapor phase condensation of methyl acetate with formaldehyde to preparing methyl acrylate over cesium supported SBA-15 catalyst

Jianbiao Yan,Chunlei Zhang,Chunli Ning,Yong Tang,Yi Zhang,Lili Chen,Shuang Gao,Zhenlu Wang,Wenxiang Zhang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.25 No.-

A cesium ion-containing catalyst, on an SBA-15 mesoporous molecular support, was prepared by the impregnation method and applied to the aldol condensation of methyl acetate with formaldehyde. The catalyst showed high catalytic activity in the condensation reaction. XRD characterization indicated that the cesium nitrate below 5 wt% loading was highly dispersed on the SBA-15 support. FT-IR and XPS results confirmed that a Si–O–Cs species was formed on the surface of the catalyst. Pyridine-IR verified that an L-acid site existed on the surface. The NH3-TPD and CO2-TPD results indicated that weak Lewis acid–base pairs were loaded on the surface, and these weak acid–base active sites might favor the aldol condensation reaction. The 5Cs/SBA-15 catalyst demonstrated the highest (48.4%) conversion of methyl acetate reported and 95.0% selectivity for methyl acrylate. The deactivated catalyst was completely regenerated by calcination. The catalyst was regenerated nine times with a total operation time of more than 60 h, and the initial conversion of methyl acetate and the selectivity for methyl acrylate did not change. The high catalytic activity was mainly due to the suitable strength of weak acid–base properties, which were rooted in the Si–O–Cs species on the surface of the support.

ANXA3, associated with YAP1 regulation, participates in the proliferation and chemoresistance of cervical cancer cells

Huang Jiazhen,Wei Wei,Kang Fuli,Tan Shuang,Li Yibing,Lu Xiaohang,Wang Ning 한국유전학회 2023 Genes & Genomics Vol.45 No.12

Background Cervical cancer, as one of the most common cancers in women, remains a major health threat worldwide. Annexin A3 (ANXA3), a component of the annexin family, is upregulated in numerous cancers, with no explicit role in cervical cancer. Objective This study aims to investigate the function of ANXA3 in cervical cancer. Methods Differential expression genes between the cervical cancer tissues of patients and the controls were analyzed in The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis (GEPIA) database. Using transfection approaches to either upregulate or downregulate ANXA3, its role in cell proliferation and chemosensitivity of human cervical cancer cell lines (HeLa and C33A) was evaluated. Furthermore, the binding activity between YAP1 and ANXA3 was also explored. Results Genomics analysis indicated that differential genes were mostly associated with cell cycle progression and DNA replication. ANXA3 was highly expressed in the cervical cancer tissues and closely linked to malignancy degree. Knockdown of ANXA3 in cervical cancer cells inhibited cell cycle progression. A similar result was observed in the reduction of cyclin D, CDK4, cyclin E, and CDK2 in cervical cancer cells with ANXA3 silencing. Cervical cancer cells obtained high sensitivity to cisplatin (DDP) when ANXA3 was downregulated. Conversely, these capabilities were the opposite in cervical cancer cells overexpressing ANXA3. Furthermore, the expression levels of ANXA3 and YAP1 were positively correlated. YAP1 upregulation was positively connected with malignant behaviors, which were reversed by ANXA3 downregulation. Conclusion In light of our findings, targeting ANXA3 expressed in cervical cancer might contribute to more potential therapeutic strategies.

Longitudinal Intrinsic Brain Activity Changes in Cirrhotic Patients before and One Month after Liver Transplantation

Yue Cheng,Li-Xiang Huang,Li Zhang,Ming Ma,Shuang-Shuang Xie,Qian Ji,Xiao-Dong Zhang,Gao-Yan Zhang,Xue-Ning Zhang,Hong-Yan Ni,Wen Shen 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.2

Objective: To evaluate the spontaneous brain activity alterations in liver transplantation (LT) recipients using resting-state functional MRI. Materials and Methods: Twenty cirrhotic patients as transplant candidates and 25 healthy controls (HCs) were included in this study. All patients repeated the MRI study one month after LT. Amplitude of low-frequency fluctuation (ALFF) values were compared between cirrhotic patients (both pre- and post-LT) and HCs as well as between the pre- and post-LT groups. The relationship between ALFF changes and venous blood ammonia levels and neuropsychological tests were investigated using Pearson’s correlation analysis. Results: In the cirrhotic patients, decreased ALFF in the vision-related regions (left lingual gyrus and calcarine), sensorimotor-related regions (left postcentral gyrus and middle cingulate cortex), and the default-mode network (bilateral precuneus and left inferior parietal lobule) were restored, and the increased ALFF in the temporal and frontal lobe improved in the early period after LT. The ALFF decreases persisted in the right supplementary motor area, inferior parietal lobule, and calcarine. The ALFF changes in the right precuneus were negatively correlated with changes in number connection test-A scores (r = 0.507, p < 0.05). Conclusion: LT improved spontaneous brain activity and the results for associated cognition tests. However, decreased ALFF in some areas persisted, and new-onset abnormal ALFF were possible, indicating that complete cognitive function recovery may need more time.

Dexmedetomidine promotes the progression of hepatocellular carcinoma through hepatic stellate cell activation

Chen Peng,Luo Xiaojun,Dai Guanqi,Jiang Yuchuan,Luo Yue,Peng Shuang,Wang Hao,Xie Penghui,Qu Chen,Lin Wenyu,Hong Jian,Ning Xue,Li Aimin 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Dexmedetomidine (DEX) is an anesthetic that is widely used in the clinic, and it has been reported to exhibit paradoxical effects in the progression of multiple solid tumors. In this study, we sought to explore the mechanism by which DEX regulates hepatocellular carcinoma (HCC) progression underlying liver fibrosis. We determined the effects of DEX on tumor progression in an orthotopic HCC mouse model of fibrotic liver. A coculture system and a subcutaneous xenograft model involving coimplantation of mouse hepatoma cells (H22) and primary activated hepatic stellate cells (aHSCs) were used to study the effects of DEX on HCC progression. We found that in the preclinical mouse model of liver fibrosis, DEX treatment significantly shortened median survival time and promoted tumor growth, intrahepatic metastasis and pulmonary metastasis. The DEX receptor (ADRA2A) was mainly expressed in aHSCs but was barely detected in HCC cells. DEX dramatically reinforced HCC malignant behaviors in the presence of aHSCs in both the coculture system and the coimplantation mouse model, but DEX alone exerted no significant effects on the malignancy of HCC. Mechanistically, DEX induced IL-6 secretion from aHSCs and promoted HCC progression via STAT3 activation. Our findings provide evidence that the clinical application of DEX may cause undesirable side effects in HCC patients with liver fibrosis.