Capacity Analysis of UWB Networks in Three-Dimensional Space

Lin X. Cai,Lin Cai,센슈민,Jon W. Mark 한국통신학회 2009 Journal of communications and networks Vol.11 No.3

Although asymptotic bounds of wireless network capacity have been heavily pursued, the answers to the following questions are still critical for network planning, protocol and architecture design: Given a three-dimensional (3D) network space with the number of active users randomly located in the space and using the wireless communication technology, what are the expected per-flow throughput, network capacity, and network transport capacity? In addition, how can the protocol parameters be tuned to enhance network performance? In this paper, we focus on the ultra wideband (UWB) based wireless personal area networks (WPANs) and provide answers to these questions, considering the salient features of UWB communications, i.e., low transmission/interference power level, accurate ranging capability, etc. Specifically, we demonstrate how to explore the spatial multiplexing gain of UWB networks by allowing appropriate concurrent transmissions. Given 3D space and the number of active users, we derive the expected number of concurrent transmissions, network capacity and transport capacity of the UWB network. The results reveal the main factors affecting network (transport) capacity, and how to determine the best protocol parameters, e.g., exclusive region size, in order to maximize the capacity. Extensive simulation results are given to validate the analytical results.

Capacity Analysis of UWB Networks in Three-Dimensional Space

Cai, Lin X.,Cai, Lin,Shen, Xuemin,Mark, Jon W. The Korea Institute of Information and Commucation 2009 Journal of communications and networks Vol.11 No.3

Although asymptotic bounds of wireless network capacity have been heavily pursued, the answers to the following questions are still critical for network planning, protocol and architecture design: Given a three-dimensional (3D) network space with the number of active users randomly located in the space and using the wireless communication technology, what are the expected per-flow throughput, network capacity, and network transport capacity? In addition, how can the protocol parameters be tuned to enhance network performance? In this paper, we focus on the ultra wideband (UWB) based wireless personal area networks (WPANs) and provide answers to these questions, considering the salient features of UWB communications, i.e., low transmission/interference power level, accurate ranging capability, etc. Specifically, we demonstrate how to explore the spatial multiplexing gain of UWB networks by allowing appropriate concurrent transmissions. Given 3D space and the number of active users, we derive the expected number of concurrent transmissions, network capacity and transport capacity of the UWB network. The results reveal the main factors affecting network (transport) capacity, and how to determine the best protocol parameters, e.g., exclusive region size, in order to maximize the capacity. Extensive simulation results are given to validate the analytical results.

Qualitative and quantitative determination of oleanolic acid in a scalp tonic products by HPLC using response surface methodology for extraction optimization

Lin Xi Cai,조종운,Yan Zhao,Jong-Seong Kang,Kyung Tae Kim,Sang-Hun Jung 한국분석과학회 2019 분석과학 Vol.32 No.2

The simple and effective analytical method for the quality control of a novel scalp tonic formulation has been developed and optimized in terms of HPLC conditions and sample preparation method, meanwhile, the optimization of preparation condition was using response surface methodology (RSM) based on central composite design (CCD). Oleanolic acid was selected as marker compound because of its bioactivities for alopecia therapy. The developed analytical method and extraction condition were successfully qualified. Coefficient of determination (r2) for the calibration was 0.9997 with a line passing through the origin point in the range of 0.1-100 mg/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) were 17.5 ng/mL and 55.0 ng/mL, respectively. The intra-day and inter-day precision of the method were 0.5-1.4 % and 0.7-1.8 % in relative standard deviation, respectively, while those accuracy were 99.5-100.9 % and 100.0- 102.2 %, respectively. The repeatability of oleanolic acid in samples ranged of 0.3-1.9 % based on peak area and 0.3-0.7 % for retention time. Recoveries from samples were 95.0-99.4 % with lower than 1.8 % in relative standard deviation. Overall, the developed analytical method will be used for quality control of this commercial scalp tonic products successfully.

Anisotropic In-plane Resistivity and Magnetoresistance of the Detwinned BaFe2As2

Lin Jiao,Zong Fa Weng,Xue Yan Tang,Lu Kai Guo,Tian Shang,Lin Yang,Hui Qiu Yuan,Yu Ying Wu,Zheng Cai Xia 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

We have measured the electrical resistivity and the magnetoresistance of detwinned BaFe2As2single crystals in fields up to 16 Tesla. The temperature dependence of the resistivity shows acounterintuitive anisotropic behavior in the ab-plane, likely arising from the effect of the nematicsusceptibility. Little magnetoresistance is observed at temperatures above the structural/magnetictransition, below which a huge in-plane magnetoresistance with an anisotropy is detected.

Mutant IDH1 Enhances Temozolomide Sensitivity via Regulation of the ATM/CHK2 Pathway in Glioma

Lin Lin,Jinquan Cai,Zixiao Tan,Xiangqi Meng,Ruiyan Li,Yang Li,Chuanlu Jiang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.2

Purpose Isocitrate dehydrogenase 1 (IDH1) mutations are the most common genetic abnormalities in low-grade gliomas and secondary glioblastomas. Glioma patients with these mutations had better clinical outcomes. However, the effect of IDH1 mutation on drug sensitivity is still under debate. Materials and MethodsIDH1-R132H mutant cells were established by lentivirus. IDH1-R132H protein expression was confirmed by western blot. The expression of ataxia telangiectasia mutated (ATM) signaling pathway and apoptosis-related proteins were detected by immunofluorescence and western blot. Temozolomide (TMZ) induced cell apoptosis was detected by flow cytometry. Tumor cell proliferation was detected by Cell Counting Kit-8. In vivo nude mice were used to confirm the in vitro roles of IDH1 mutation.ResultsWe established glioma cell lines that expressed IDH1-R132H mutation stably. We found that TMZ inhibited glioma cells proliferation more significantly in IDH1 mutant cells compared to wild type. The IC50 of TMZ in IDH1-R132H mutant group was less than half that of wild-type group (p < 0.01). TMZ significantly induced more DNA damage (quantification of γH2AX expression in IDH1 mutation vs. wild type, p < 0.05) and apoptosis (quantification of AnnexinV+propidium iodide–cells in IDH1 mutation versus wild type, p < 0.01) in IDH1 mutant gliomas compared to wild-type gliomas. The ATM-associated DNA repair signal was impaired in IDH1 mutant cells. Inhibiting the ATM/checkpoint kinase 2DNA repair pathway further sensitized IDH1 mutant glioma cells to chemotherapy. We found that IDH1 mutation significantly inhibited tumor growth in vivo (the tumor size was analyzed statistically, p < 0.05). Moreover, we confirmed that gliomas with IDH1 mutation were more sensitive to TMZ in vivo compared to wild type significantly and the results were consistent with the in vitro experiment. ConclusionThese results provide evidence that combination of TMZ and ATM inhibitor enhances the antitumor effect in IDH1 mutant gliomas.

Study properties of soft subgrade soil stabilized by sewage sludge/lime and nano-SiO₂

Lin, Deng-Fong,Luo, Huan-Lin,Chen, Chien-Ta,Cai, Ming-Du Techno-Press 2016 Geomechanics & engineering Vol.10 No.6

The pozzolanic characteristics of a sludge incinerated into ash were determined in this study. Lime is commonly used as a stabilizer for the treatment of soils, whereas sewage sludge ash (SSA) is often applied with lime to improve soft subgrade soil. In this study, a cohesive soil categorized as A-4 (low-plasticity clay) by AASHTO classifications was mixed with SSA/lime with a 3:1 ratio. Nano-$SiO_2$ was also added to the soil. To identify changes in the workability, strength, permeability, and shear strength of the soft subgrade soil, basic soil tests were conducted, and the microstructure of the treated soil was analyzed. The results indicate that SSA/lime mixtures improve the properties of soft subgrade soil and transform the soil from "poor subgrade soil" to "good to excellent subgrade soil" with a CBR > 8. Additionally, the addition of 2% nano-$SiO_2$ increases the unconfined compressive strength of soft subgrade soil treated with SSA/lime mixture by approximately 17 kPa. However, the swelling of the treated soil increased by approximately 0.1% after the addition of nano-$SiO_2$ and lime. Thus, soil swelling should be considered before lime and nano-$SiO_2$ are applied to soft subgrade soil.

An Arabidopsis SUMO E3 Ligase, SIZ1, Negatively Regulates Photomorphogenesis by Promoting COP1 Activity

Lin, Xiao-Li,Niu, De,Hu, Zi-Liang,Kim, Dae Heon,Jin, Yin Hua,Cai, Bin,Liu, Peng,Miura, Kenji,Yun, Dae-Jin,Kim, Woe-Yeon,Lin, Rongcheng,Jin, Jing Bo Public Library of Science 2016 PLoS genetics Vol.12 No.4

<P>COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1), a ubiquitin E3 ligase, is a central negative regulator of photomorphogenesis. However, how COP1 activity is regulated by post-translational modifications remains largely unknown. Here we show that SUMO (small ubiquitin-like modifier) modification enhances COP1 activity. Loss-of-function siz1 mutant seedlings exhibit a weak constitutive photomorphogenic phenotype. SIZ1 physically interacts with COP1 and mediates the sumoylation of COP1. A K193R substitution in COP1 blocks its SUMO modification and reduces COP1 activity in vitro and in planta. Consistently, COP1 activity is reduced in siz1 and the level of HY5, a COP1 target protein, is increased in siz1. Sumoylated COP1 may exhibits higher transubiquitination activity than does non-sumoylated COP1, but SIZ1-mediated SUMO modification does not affect COP1 dimerization, COP1-HY5 interaction, and nuclear accumulation of COP1. Interestingly, prolonged light exposure reduces the sumoylation level of COP1, and COP1 mediates the ubiquitination and degradation of SIZ1. These regulatory mechanisms may maintain the homeostasis of COP1 activity, ensuing proper photomorphogenic development in changing light environment. Our genetic and biochemical studies identify a function for SIZ1 in photomorphogenesis and reveal a novel SUMO-regulated ubiquitin ligase, COP1, in plants.</P>

Qualitative and quantitative determination of oleanolic acid in a scalp tonic products by HPLC using response surface methodology for extraction optimization

Cai, Lin Xi,Cho, Chong Woon,Zhao, Yan,Kang, Jong Seong,Kim, Kyung Tae,Jung, Sang-Hun The Korean Society of Analytical Science 2019 분석과학 Vol.32 No.2

The simple and effective analytical method for the quality control of a novel scalp tonic formulation has been developed and optimized in terms of HPLC conditions and sample preparation method, meanwhile, the optimization of preparation condition was using response surface methodology (RSM) based on central composite design (CCD). Oleanolic acid was selected as marker compound because of its bioactivities for alopecia therapy. The developed analytical method and extraction condition were successfully qualified. Coefficient of determination ($r^2$) for the calibration was 0.9997 with a line passing through the origin point in the range of 0.1-100 mg/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) were 17.5 ng/mL and 55.0 ng/mL, respectively. The intra-day and inter-day precision of the method were 0.5-1.4 % and 0.7-1.8 % in relative standard deviation, respectively, while those accuracy were 99.5-100.9 % and 100.0-102.2 %, respectively. The repeatability of oleanolic acid in samples ranged of 0.3-1.9 % based on peak area and 0.3-0.7 % for retention time. Recoveries from samples were 95.0-99.4 % with lower than 1.8 % in relative standard deviation. Overall, the developed analytical method will be used for quality control of this commercial scalp tonic products successfully.

Diagnostic Significance of Combined Detection of Epstein-Barr Virus Antibodies, VCA/IgA, EA/IgA, Rta/IgG and EBNA1/IgA for Nasopharyngeal Carcinoma

Cai, Yong-Lin,Li, Jun,Lu, Ai-Ying,Zheng, Yu-Ming,Zhong, Wei-Ming,Wang, Wei,Gao, Jian-Quan,Zeng, Hong,Cheng, Ji-Ru,Tang, Min-Zhong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.5

The objective of this study was to investigate the diagnostic significance of EBV antibody combined detection for nasopharyngeal carcinoma (NPC) in a high incidence region of southern China. Two hundred and eleven untreated NPC patients, 203 non-NPC ENT patients, and 210 healthy controls were recruited for the study. The titers of VCA/IgA and EA/IgA were assessed by immunoenzyme assay, and the levels of Rta/IgG and EBNA1/IgA were determined by enzyme-linked immunosorbent assay. The levels of VCA/IgA, EA/IgA, Rta/IgG and EBNA1/IgA demonstrated no association with gender or age (p>0.05). The receiver operating characteristic curve and the area under the curve were used to evaluate the diagnostic value. The sensitivity of VCA/IgA (98.1%) and the specificity of EA/IgA (98.5%) were the highest. When a logistic regression model was used to combine the results from multiple antibodies to increase the accuracy, the combination of VCA/IgA+Rta/IgG, whose area under the curve was 0.99, had the highest diagnostic efficiency, and its sensitivity, specificity and Youden index were 94.8%, 98.0% and 0.93 respectively. The data suggest that the combination of VCA/IgA+Rta/IgG may be most suitable for NPC serodiagnosis.

Pressure-induced semiconductor-to-metal phase transition of a charge-ordered indium halide perovskite

Lin, Jia,Chen, Hong,Gao, Yang,Cai, Yao,Jin, Jianbo,Etman, Ahmed S.,Kang, Joohoon,Lei, Teng,Lin, Zhenni,Folgueras, Maria C.,Quan, Li Na,Kong, Qiao,Sherburne, Matthew,Asta, Mark,Sun, Junliang,Toney, Mic National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.47

<P><B>Significance</B></P><P>Metal halide perovskites attract great interest for a wide range of applications due to their remarkable optoelectronic properties. The development of environmentally friendly halide perovskite materials with various crystal structures and compositions offers unprecedented opportunities to achieve desired properties and applications. In this work, we demonstrated an In-based, charge-ordered all-inorganic halide double perovskite with the composition of Cs<SUB>2</SUB>In(I)In(III)Cl<SUB>6</SUB> synthesized by solid-state reaction. High-pressure optical properties were studied, and a pressure-driven, fully reversible semiconductor–metal phase transition was discovered. This In-based charge-ordered structure may inspire new understanding of halide perovskite as well as provide a platform for future discovery of exotic electronic phenomena such as high-<I>T</I><SUB>C</SUB> superconductivity in halide perovskite compounds.</P><P>Phase transitions in halide perovskites triggered by external stimuli generate significantly different material properties, providing a great opportunity for broad applications. Here, we demonstrate an In-based, charge-ordered (In<SUP>+</SUP>/In<SUP>3+</SUP>) inorganic halide perovskite with the composition of Cs<SUB>2</SUB>In(I)In(III)Cl<SUB>6</SUB> in which a pressure-driven semiconductor-to-metal phase transition exists. The single crystals, synthesized via a solid-state reaction method, crystallize in a distorted perovskite structure with space group <I>I</I>4/<I>m</I> with <I>a</I> = 17.2604(12) Å, <I>c</I> = 11.0113(16) Å if both the strong reflections and superstructures are considered. The supercell was further confirmed by rotation electron diffraction measurement. The pressure-induced semiconductor-to-metal phase transition was demonstrated by high-pressure Raman and absorbance spectroscopies and was consistent with theoretical modeling. This type of charge-ordered inorganic halide perovskite with a pressure-induced semiconductor-to-metal phase transition may inspire a range of potential applications.</P>