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A modulated broadband polarimetric insensitive metamaterial absorber based on a monolayer of graphene
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作者 Xin Ning Tangyou Sun +5 位作者 Qianju Song Zao Yi Shubo Cheng Junqiao Wang Qingdong Zeng Yougen Yi 《Communications in Theoretical Physics》 2025年第9期159-169,共11页
This paper presents a tunable and polarization-insensitive wideband metamaterial absorber based on single-layer graphene.By comparing the simulated experimental data with theoretical derivations,it was found that the ... This paper presents a tunable and polarization-insensitive wideband metamaterial absorber based on single-layer graphene.By comparing the simulated experimental data with theoretical derivations,it was found that the absorbance of the material can be sustained above 90%in the frequency range of 2.78 to 7.14(4.36)THz,of which the absorption rate exceeds 99%in the frequency range of 4.1–4.54(0.44)THz,and remarkably,perfect absorption is achieved at4.32 THz.In the range of 2.78–7.14 THz,the average absorption rate is 96.1%,by adjusting the physical size of the graphene layer pattern,we can modify the working band gap of the absorber.By applying a voltage to modulate the Fermi level of graphene,we can increase the absorption bandwidth.When the chemical potential is 1.0 e V,at the bandwidth of 4.36 THz,its absorption rate exceeds 90%.The working principle of absorbing materials was deeply explored using the principles of electromagnetic field distribution and impedance adaptation.Through detailed analysis of different polarization states and incident angles,we found that the absorber is not sensitive to polarization due to its symmetrical structure,and found that it exhibits low sensitivity at incidence angles.In addition,after comparative analysis,significant differences were observed in the absorption efficiency of the absorber under various relaxation time conditions,and the obtained data were elaborated in detail using the carrier mechanism of plasma vibration.We found that in addition to obtaining an almost perfect absorber with wide band by adjusting the parameters,it is also feasible to obtain an approximately narrow band absorber by changing the relaxation time without having to remanufacture the structure.The absorber offers several advantages,including tunability,a wide absorption band,a high absorption rate,polarization insensitivity,and a simple structure.Therefore,this absorber exhibits great potential for absorption,monitoring,and sensing in the terahertz band. 展开更多
关键词 GRAPHENE perfect absorption BROADBAND polarization insensitivity
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Androgen receptor mutations in familial androgen insensitivity syndrome:A metabolic reprogramming pathway to type 2 diabetes susceptibility
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作者 Cheng Luo Wei-Wei Zhang +9 位作者 Liang-Yan Hua Mei-Qi Zeng Hui Xu Cheng-Zheng Duan Shi-Yu Xu Shuo Zhan Xiao-Fei Pan Da Sun Li-Ya Ye Dong-Juan He 《World Journal of Diabetes》 2025年第11期28-45,共18页
Familial androgen insensitivity syndrome (AIS), resulting from inherited mutations in the androgen receptor (AR)gene, has traditionally been examined within the framework of disorders of sex development. However, grow... Familial androgen insensitivity syndrome (AIS), resulting from inherited mutations in the androgen receptor (AR)gene, has traditionally been examined within the framework of disorders of sex development. However, growingevidence indicates that AR dysfunction also disrupts systemic metabolic homeostasis, predisposing affectedindividuals to insulin resistance and type 2 diabetes mellitus. This article synthesizes recent advances in genetics,transcriptomics, and physiology to elucidate how AR mutations drive tissue-specific metabolic reprogramming inkey organs, including pancreatic β-cells, skeletal muscle, liver, and adipose tissue. Particular attention is given to anewly identified familial AR variant (c.2117A>G;p.Asn706Ser), which not only broadens the known mutationalspectrum of AIS but also underscores the clinical importance of early metabolic risk screening in this population.We further examine how pubertal stage, hormone replacement therapy, and sex-specific signaling pathwaysinteract to influence long-term metabolic outcomes. Lastly, we propose an integrative management framework thatincorporates genetic diagnosis, endocrine surveillance, and personalized pharmacological strategies aimed atreducing the risk of type 2 diabetes mellitus and cardiometabolic complications in individuals with AIS. Distinctfrom previous AIS-centered reviews, this work integrates metabolic and endocrine perspectives into the traditionaldevelopmental paradigm, offering a more comprehensive understanding of disease risk and translational management. 展开更多
关键词 Androgen insensitivity syndrome Androgen receptor Gene mutation Metabolic reprogramming Type 2 diabetes
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Mean-reverting diffusion model-enhanced acoustic-resolution photoacoustic microscopy for resolution enhancement:Toward optical resolution
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作者 Yiyang Cao Shunfeng Lu +7 位作者 Cong Wan Yiguang Wang Xuan Liu Kangjun Guo Yubin Cao Zilong Li Qiegen Liu Xianlin Song 《Journal of Innovative Optical Health Sciences》 2025年第2期130-149,共20页
Acoustic-resolution photoacoustic microscopy(AR-PAM)suffers from degraded lateral resolution due to acoustic diffraction.Here,a resolution enhancement strategy for AR-PAM via a mean-reverting diffusion model was propo... Acoustic-resolution photoacoustic microscopy(AR-PAM)suffers from degraded lateral resolution due to acoustic diffraction.Here,a resolution enhancement strategy for AR-PAM via a mean-reverting diffusion model was proposed to achieve the transition from acoustic resolution to optical resolution.By modeling the degradation process from high-resolution image to low-resolution AR-PAM image with stable Gaussian noise(i.e.,mean state),a mean-reverting diffusion model is trained to learn prior information of the data distribution.Then the learned prior is employed to generate a high-resolution image from the AR-PAM image by iteratively sampling the noisy state.The performance of the proposed method was validated utilizing the simulated and in vivo experimental data under varying lateral resolutions and noise levels.The results show that an over 3.6-fold enhancement in lateral resolution was achieved.The image quality can be effectively improved,with a notable enhancement of∼66%in PSNR and∼480%in SSIM for in vivo data. 展开更多
关键词 Acoustic-resolution photoacoustic microscopy mean-reverting di®usion model gen-erative model resolution enhancement Noise insensitive
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Evidence That the Auxin Signaling Pathway Interacts with Plant Stress Response 被引量:7
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作者 包方 李家洋 《Acta Botanica Sinica》 CSCD 2002年第5期532-536,共5页
Auxin influences a variety of developmental and physiological processes. Early reports, suggested that auxin might affect plant stress response. We have identified a number of auxin responsive genes in Arabidopsis tha... Auxin influences a variety of developmental and physiological processes. Early reports, suggested that auxin might affect plant stress response. We have identified a number of auxin responsive genes in Arabidopsis thaliana (L.) Heynh. by using cDNA an-ay and found that stress responsive genes, such as,Arabidopsis homolog of MEK kinase 1 (ATMEKK1), ReL/SpoT homolog 3 ( At-RSH3), Catalase 1 ( Cat1) and Ferritin 1 (Fer1), were down-regulated by auxin, indicating that auxin regulates ale expression of stress responsive genes. We also demonstrated that nitrilase genes, nitrilase I ( NIT]) and nitrilase 2 (NIT2) involving in indole-3-acetic acid (IAA) biosynthesis, were induced by salinity stress, suggesting that the level of IAA might increase in response to salinity stress. To dissect the signal pathway involved in the interaction, two auxin insensitive mutants, auxin resistant 2 (axr2) and auxin resistant 1-3 (axrl-3) were used. Stress responsive genes were induced by salt stress in wild type and axr2, but not in axr1-3. The result suggests that die interaction between auxin and stress responses may be linked in the ubiquitin pathway. 展开更多
关键词 AUXIN stress-responsive genes auxin insensitive mutants NITRILASE Arabidopsis thaliana
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1550nm Polarization-Insensitive Semiconductor Optical Amplifier Based on AlGaInAs-InP
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作者 马宏 朱光喜 易新建 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第7期745-748,共4页
Polarization insensitive AlGaInAs InP semiconductor optical amplifier is realized at a wavelength of 1550nm.The active layer consists of three tensile strained wells with strain 0 40%.The amplifiers are fabricated ... Polarization insensitive AlGaInAs InP semiconductor optical amplifier is realized at a wavelength of 1550nm.The active layer consists of three tensile strained wells with strain 0 40%.The amplifiers are fabricated to ridge waveguide structure with 7° tilted cavity.The two facets are coated with two layers of anti reflection Ti 3O 5/Al 2O 3 films.Residual facet reflectivity is found to be less than 0 03%.The semiconductor optical amplifer exhibits 20dB of signal gain and 7 2dBm of saturation output power with an excellent polarization insensitivity (less than 0 8dB) at 200mA and 1540nm window. 展开更多
关键词 polarization insensitive AlGaInAs InP optical amplifier MOCVD
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Phenotypic heterogeneity of mutations in androgen receptor gene 被引量:23
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作者 Singh Rajender Lalji Singh Kumarasamy Thangaraj 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第2期147-179,共33页
Androgen receptor (AR) gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat (CAG and GGN) length polymorphisms have been an additional subject ... Androgen receptor (AR) gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat (CAG and GGN) length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens. 展开更多
关键词 androgen receptor androgen insensitivity prostate cancer breast cancer CAG repeat GGN repeat
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Insensitive energetic microspheres DAAF/RDX fabricated by facile molecular self-assembly 被引量:10
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作者 Shu-jie Liu Bi-dong Wu +4 位作者 Jia-ni Xie Zhi-min Li Chong-wei An Jing-yu Wang Xiao-dong Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1775-1781,共7页
Insensitive energetic materials are promising in the defense weapons field.However,energetic materials still suffer from great challenges and the concern about their safety limits their utilization.In this work,insens... Insensitive energetic materials are promising in the defense weapons field.However,energetic materials still suffer from great challenges and the concern about their safety limits their utilization.In this work,insensitive energetic explosive 3,30-diamino-4,40-azoxyfurazan/hexahydro-1,3,5-trinitro-1,3,5-triazine(DAAF/RDX)microspheres were fabricated by self-assembly method.Rod-like DAAF/RDX was prepared by mechanical ball milling for comparison.DAAF/RDX composites with different mass ratios(90:10,80:20,and 70:30)were obtained.The morphologies and structures of as-obtained DAAF/RDX composites were characterized by scanning electron microscopy(SEM),powder x-ray diffraction(PXRD)and fourier transform infrared spectroscopy(FT-IR).The results showed that DAAF/RDX microspheres exhibited regular shaped microspheres with sizes from 0.5 to 1.2 mm.There was no crystal transition during the modification process.The thermal properties of as-obtained materials were then evaluated by differential scanning calorimetry(DSC)and materials studio software.DAAF/RDX microspheres showed an advanced decomposition peak temperature compared with rod-like DAAF/RDX.The binding energy and peak temperature values at zeroβ_(i)(T_(P0))of DAAF/RDX(90:10)increased by 36.77 kJ/mol,1.6℃,and 58.11 kJ/mol,12.3℃compared to DAAF/RDX(80:20)and DAAF/RDX(70:30),indicating the better thermal stability of DAAF/RDX(90:10).The characteristic drop height(H_(50))of DAAF/RDX(higher than 100 cm)composites was higher than that of raw RDX(25 cm),suggesting significant improvements in mechanical safety.The preparation of DAAF/RDX microspheres is promising for the desensitization of RDX and useful for the formation of other materials and future wide applications. 展开更多
关键词 DAAF RDX Insensitive Energetic microspheres Thermal stability
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Wide-Band Polarization-Independent Semiconductor Optical Amplifier Gate with Tensile-Strained Quasi-Bulk InGaAs
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作者 王书荣 刘志宏 +6 位作者 王圩 朱洪亮 张瑞英 丁颖 赵玲娟 周帆 王鲁峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期898-902,共5页
A semiconductor optical amplifier gate based on tensile strained quasi bulk InGaAs is developed.At injection current of 80mA,a 3dB optical bandwidth of more than 85nm is achieved due to dominant band filling effect... A semiconductor optical amplifier gate based on tensile strained quasi bulk InGaAs is developed.At injection current of 80mA,a 3dB optical bandwidth of more than 85nm is achieved due to dominant band filling effect.Moreover,the most important is that very low polarization dependence of gain (<0 7dB),fiber to fiber lossless operation current (70~90mA) and a high extinction ratio (>50dB) are simultaneously obtained over this wide 3dB optical bandwidth (1520~1609nm) which nearly covers the spectral region of the whole C band (1525~1565nm) and the whole L band (1570~1610nm).The gating time is also improved by decreasing carrier lifetime.The wide band polarization insensitive SOA gate is promising for use in future dense wavelength division multiplexing (DWDM) communication systems. 展开更多
关键词 semiconductor optical amplifier gate wide bandwidth polarization insensitive tensile strained quasi bulk InGaAs fiber to fiber lossless operation current extinction ratio
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Electrostaticspray preparation and properties of RDX/DOS composites 被引量:6
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作者 Jian Yao Jian Liu +2 位作者 Yong-xu Wang Bin Li Li-feng Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2017年第4期263-268,共6页
A composite explosive based on 1,3,5-trinitro-1,3,5-triazinane(RDX)was prepared by electrostaticspray method with dioctyl sebacate(DOS)as desensitizer.After preparation,the particle size and crystal structure were cha... A composite explosive based on 1,3,5-trinitro-1,3,5-triazinane(RDX)was prepared by electrostaticspray method with dioctyl sebacate(DOS)as desensitizer.After preparation,the particle size and crystal structure were characterized and chemical features,such as chemical bonds,functional groups,thermal decomposition parameters and mechanical sensitivity were investigated as well.In terms of the morphologies of the composites,the particle sizes were in the range of 1e3 mm.Compared with RDX,the crystal types,chemical bonds and functional groups of the RDX/DOS composites were unchanged.The activation energy of the composites was lower than that of raw RDX,and the 3wt%DOS composites had the lowest activation energy.The impact sensitivity and friction sensitivity of the RDX/DOS composites were lower than those of raw RDX,and the 10wt%DOS composites had the highest H50(125.9 cm)and the lowest friction sensitivity(8%). 展开更多
关键词 RDX DOS Electrostaticspray COMPOSITES Insensitive
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Phenotypic and molecular characteristics of androgen insensitivity syndrome patients 被引量:7
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作者 Shi-Min Yuan Ya-Nan Zhang +6 位作者 Juan Du Wen Li Chao-Feng Tu Lan-Lan Meng Ge Lin Guang-Xiu Lu Yue-Qiu Tan 《Asian Journal of Andrology》 SCIE CAS CSCD 2018年第5期473-478,共6页
Androgen insensitivity syndrome (AIS), an X-linked recessive genetic disorder of sex development, is caused by mutations in the androgen receptor (AR) gene, and is characterized by partial or complete inability of... Androgen insensitivity syndrome (AIS), an X-linked recessive genetic disorder of sex development, is caused by mutations in the androgen receptor (AR) gene, and is characterized by partial or complete inability of specific tissues to respond to androgens in individuals with the 46,XY karyotype. This study aimed to investigate AR gene mutations and to characterize genotype-phenotype correlations. Ten patients from unrelated families, aged 2-31 years, were recruited in the study. Based on karyotype, altered hormone profile, and clinical manifestations, nine patients were preliminarily diagnosed with complete AIS and one with partial AIS. Genetic analysis of AR gene revealed the existence of 10 different mutations, of which five were novel (c.2112 C〉G[p.STO4R], c.2290T〉A[p.Y764N], c.2626C〉T[p.Q876X], c.933dupC[p.K313Qfs*28], and c.1067delC[p.A356Efs*123]); the other five were previously reported (c.1789G〉A[p.A597T], c.2566C〉T[p.R856C], c.2668G〉A[p.V890M], c.2679C〉T[p.P893L], and c.1605C〉G[p.Y535X]). Regarding the distribution of these mutations, 60.0% were clustered in the ligand-binding domain of AR gene. Exons 1 and 8 of AR gene each accounted for 30.0% (3/10) of all mutations. Most of the truncation mutations were in exon 1 and missense mutations were mainly located in exons 4-8. Our study expands the spectrum of AR gene mutations and confirms the usefulness of AR gene sequencing to support a diagnosis of AIS and to enable prenatal or antenatal screening. 展开更多
关键词 androgen insensitivity syndrome androgen receptor disorder of sex development MUTATION
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QTL Identification of the Insensitive Response to Photoperiod and Temperature in Soybean by Association Mapping 被引量:6
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作者 ZUO Qiao-mei WEN Zi-xiang +4 位作者 ZHANG Shu-yun HOU Jin-feng GAI Jun-yi YU De-yue XING Han 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1423-1430,共8页
The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 2... The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 275 accessions of soybean [Glycine max (L.) Merrill] from China. Genome-wide association mapping, based on population structure analysis, was carried out using 118 SSR markers by the TASSEL GLM (general linear model) program. Nine SSR markers (P〈0.01) were associated with the value of the response to photoperiod and temperature (VRPT) caused by days to flowering (DF), among which, Satt308 (LG M), Sattl50 (LG M) and Satt440 (LG l), were identified in both 2006 and 2007. Twelve SSR markers (P〈0.01) were associated with VRPT caused by days to maturity (DM), among which three markers, Satt387 (LG N), Satt307 (LG C2) and AW310961 (LG J), were detected in both 2006 and 2007. In addition, a total of 20 elite alleles were screened out over 2006 and 2007 for being associated with an insensitive response to photoperiod and temperature (IRPT) caused by DF and a total of seven different elite alleles were screened out for being associated with IRPT caused by DM. Among these elite alleles, five alleles, Satt150-244, Satt308-164, Satt308-206, Satt440-176, and Satt440-206, were associated with IRPT caused by DF and were identified in both years, but only one allele, Satt307-170, was identified as being associated with an IRPT caused by DM. Based on these elite alleles, a set of typical accessions were screened out. The result about the genetic basis of IRPT is meaningful for soybean wide adaption breeding. 展开更多
关键词 QTL association mapping SOYBEAN insensitive response photoperiod and temperature
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Insensitive high explosives:Ⅳ. Nitroguanidine-Initiation & detonation 被引量:3
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作者 Ernst-Christian Koch 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第4期467-487,共21页
This paper reviews the detonative properties of low bulk density(LBD),high bulk density(HBD)Nitroguanidine(NGu)(1),CAS-No:[556-88-7]and 82 explosive formulations based on NGu reported in the public domain.To rank the ... This paper reviews the detonative properties of low bulk density(LBD),high bulk density(HBD)Nitroguanidine(NGu)(1),CAS-No:[556-88-7]and 82 explosive formulations based on NGu reported in the public domain.To rank the performance of those formulations they are compared with 15 reference compositions containing both standard high explosives such as octogen(HMX)(2),hexogen(RDX)(3),pentaerythritol tetranitrate(PETN)(4),2,4,6-trinitrotoluene(TNT)(5)as well as insensitive high explosives such as 3-nitro-1,2,4-triazolone(NTO)(6),1,3,5-triamino-2,4,6-trinitrobenzene(TATB)(7),1,1-diamino-2,2-dinitroethylene(FOX-7)(8)and N-Guanylurea dinitramide(FOX 12)(9).NGu based formulations are superior to those based on FOX-12 or TATB and are a close match with FOX-7 based explosives,the latter just having higher Gurney Energies(-10%)and slightly higher detonation pressure(+2%).NGu based explosives even reach up to 78% of the detonation pressure,82% Gurney energy and up to 95% of detonation velocity of HMX.LBD-NGu dissolves in many melt cast eutectics forming dense charges thereby eliminating the need for costly High Bulk Density NGu.Nitroguanidine based formulations are at the rock bottom of sensitiveness among all the above-mentioned explosives which contributes to the safety of these formulations.The review gives 132 references to the public domain.For a review on the synthesis spectroscopy and sensitiveness of Nitroguanidine see Ref.[1]. 展开更多
关键词 Cook-off DETONATION Insensitive munitions NITROGUANIDINE Shock sensitvity
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Novel mutation in the ligand-binding domain of the androgen receptor gene (1790p) associated with complete androgen insensitivity syndrome 被引量:6
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作者 Florina Raicu Rossella Giuliani +5 位作者 Valentina Gatta Chiara Palka Paolo Guanciali Franchi Pierluigi Lelli-Chiesa Stefano Tumini Liborio Stuppia 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第4期687-691,共5页
Mutations in the X-linked androgen receptor (AR) gene cause androgen insensitivity syndrome (AIS), resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity (CAI... Mutations in the X-linked androgen receptor (AR) gene cause androgen insensitivity syndrome (AIS), resulting in an impaired embryonic sex differentiation in 46,XY genetic men. Complete androgen insensitivity (CAIS) produces a female external phenotype, whereas cases with partial androgen insensitivity (PALS) have various ambiguities of the genitalia. Mild androgen insensitivity (MAIS) is characterized by undermasculinization and gynecomastia. Here we describe a 2-month-old 46,XY female patient, with all of the characteristics of CAIS. Defects in testosterone (T) and dihydrotestosterone (DHT) synthesis were excluded. Sequencing of the AR gene showed the presence in exon 6 of a T to C transition in the second base of codon 790, nucleotide position 2369, causing a novel missense Leu790Pro mutation in the ligand-binding domain of the AR protein. The identification of a novel AR mutation in a girl with CAIS provides significant information due to the importance of missense mutations in the ligand-binding domain of the AR, which are able to induce functional abnormalities in the androgen binding capability, stabilization of active conformation, or interaction with coactivators. 展开更多
关键词 androgen receptor novel androgen receptor gene mutation complete androgen insensitivity syndrome
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Realization of THz dualband absorber with periodic cross-shaped graphene metamaterials 被引量:3
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作者 Chunzhen Fan Yuchen Tian +1 位作者 Peiwen Ren Wei Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期370-374,共5页
A dualband terahertz(THz) absorber including periodically distributed cross-shaped graphene arrays and a gold layer spaced by a thin dielectric layer is investigated.Numerical results reveal that the THz absorber disp... A dualband terahertz(THz) absorber including periodically distributed cross-shaped graphene arrays and a gold layer spaced by a thin dielectric layer is investigated.Numerical results reveal that the THz absorber displays two perfect absorption peaks.To elucidate the resonant behavior, the LC model is introduced to fit the spectra.Moreover, the strength and linewidth of the absorption peak can be effectively tuned with structural parameters and the relaxation time of graphene.Owing to its rotational symmetry, this THz absorber exhibits polarization insensitivity.Our designed absorber is a promising candidate in applications of tunable optical sensors and optical filters. 展开更多
关键词 DUALBAND terahertz ABSORBER GRAPHENE polarization INSENSITIVITY
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Parametric study of single confined fragment launch explosive device 被引量:3
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作者 Pankaj K.Choudha A.Kumaraswamy Kusumkant D.Dhote 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第2期179-185,共7页
In this article, parametric study of single confined fragment launch device was carried out. The configuration proposed was further studied to derive the empirical relationship for effect of fragment size,charge size,... In this article, parametric study of single confined fragment launch device was carried out. The configuration proposed was further studied to derive the empirical relationship for effect of fragment size,charge size, confinement thickness on fragment velocity. The simulations were carried out using ANSYSAUTODYNE explicit solver. Fragment velocities were estimated as a function of different parametric combinations of explosive quantities, charge length to diameter ratio, fragment height to diameter ratio,confinement thickness, fragment material and fragment mass. The data was further converted to charge to metal ratio under fragment and confinement. It was observed that, increase in confinement thickness,charge quantity and decrease in fragment height increases the fragment velocity. It is also noted that,charge to metal mass ratio under fragment significantly affects the fragment velocity. At the end, an empirical relationship for fragment velocity interms of all these parameters was established. Using these relations, two velocities 1831.92 m/s and 2523.9 m/s required for NATO STANAG 4496 IM test were estimated. The design parameters for these velocities are presented. Also, the results estimated using the empirical relationship has been compared with published experimental data. Error in the predicted velocities is within the acceptable range. The empirical relationship proposed will be useful for finalization of design of the fragment launch device. 展开更多
关键词 CONFINEMENT FRAGMENT size Empirical relationship FRAGMENT velocity Insensitive munition test FRAGMENT LAUNCHING DEVICE
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Imperfection sensitivity of mechanical properties in soft network materials with horseshoe microstructures 被引量:3
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作者 Jianxing Liu Xinyuan Zhu +1 位作者 Zhangming Shen Yihui Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2021年第7期1050-1062,I0001,共14页
Developments of soft network materials with rationally distributed wavy microstructures have enabled many promising applications in bio-integrated electronic devices,due to their abilities to reproduce precisely nonli... Developments of soft network materials with rationally distributed wavy microstructures have enabled many promising applications in bio-integrated electronic devices,due to their abilities to reproduce precisely nonlinear mechanical properties of human tissues/organs.In practical applications,the soft network materials usually serve as the encapsulation layer and/or substrate of bio-integrated electronic devices,where deterministic holes can be utilized to accommodate hard chips,thereby increasing the filling ratio of the device system.Therefore,it is essential to understand how the hole-type imperfection affects the stretchability of soft network materialswith various geometric constructions.Thiswork presents a systematic investigation of the imperfection sensitivity of mechanical properties in soft network materials consisting of horseshoe microstructures,through combined computational and experimental studies.A factor of imperfection insensitivity of stretchability is introduced to quantify the influence of hole imperfections,as compared to the case of perfect soft network materials.Such factor is shown to have different dependences on the arc angle and normalized width of horseshoe microstructures for triangular network materials.The soft triangular and Kagome network materials,especially with the arc angle in the range of(30?,60?),are found to be much more imperfection insensitive than corresponding traditional lattice materials with straight microstructures.Differently,the soft honeycomb network materials are not as imperfection insensitive as traditional honeycomb lattice materials. 展开更多
关键词 Imperfect network material Imperfection insensitivity Microstructure shape Lattice topology Stretchability
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Facile Preparation of Polypeptides:Moisture Insensitive and Superfast Ring Opening Polymerization of N-Carboxyanhydrides 被引量:3
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作者 栾世方 《材料导报》 EI CAS CSCD 北大核心 2019年第1期1-2,共2页
(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of po... (a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization. 展开更多
关键词 FACILE PREPARATION polypeptides:moisture insensitive
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Simulation based on a modified social force model for sensitivity to emergency signs in subway station 被引量:3
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作者 蔡征宇 周汝 +2 位作者 崔银锴 王妍 蒋军成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期175-183,共9页
The subway is the primary travel tool for urban residents in China. Due to the complex structure of the subway and high personnel density in rush hours, subway evacuation capacity is critical. The subway evacuation mo... The subway is the primary travel tool for urban residents in China. Due to the complex structure of the subway and high personnel density in rush hours, subway evacuation capacity is critical. The subway evacuation model is explored in this work by combining the improved social force model with the view radius using the Vicsek model. The pedestrians are divided into two categories based on different force models. The first category is sensitive pedestrians who have normal responses to emergency signs. The second category is insensitive pedestrians. By simulating different proportions of the insensitive pedestrians, we find that the escape time is directly proportional to the number of insensitive pedestrians and inversely proportional to the view radius. However, when the view radius is large enough, the escape time does not change significantly, and the evacuation of people in a small view radius environment tends to be integrated. With the improvement of view radius conditions, the escape time changes more obviously with the proportion of insensitive pedestrians. A new emergency sign layout is proposed, and the simulations show that the proposed layout can effectively reduce the escape time in a small view radius environment. However, the evacuation effect of the new escape sign layout on the large view radius environment is not apparent. In this case, the exit setting emerges as an additional factor affecting the escape time. 展开更多
关键词 modified social force model emergency evacuation insensitive pedestrians emergency signs layout
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A new Ignition-Growth reaction rate model for shock initiation 被引量:3
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作者 Yang Yang Zhuo-ping Duan +4 位作者 Shu-rui Li Lian-sheng Zhang Feng-lei Huang Yong Han Hui Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第5期126-136,共11页
Accurately predicting reactive flow is a challenge when characterizing an explosive under external shock stimuli as the shock initiation time is on the order of a microsecond.The present study constructs a new Ignitio... Accurately predicting reactive flow is a challenge when characterizing an explosive under external shock stimuli as the shock initiation time is on the order of a microsecond.The present study constructs a new Ignition-Growth reaction rate model,which can describe the shock initiation processes of explosives with different initial densities,particle sizes and loading pressures by only one set of model parameters.Compared with the Lee-Tarver reaction rate model,the new Ignition-Growth reaction rate model describes better the shock initiation process of explosives and requires fewer model parameters.Moreover,the shock initiation of a 2,4-Dinitroanisole(DNAN)-based melt-cast explosive RDA-2(DNAN/HMX(octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazoncine)/aluminum)are investigated both experimentally and numerically.A series of shock initiation experiments is performed with manganin piezoresistive pressure gauges and corresponding numerical simulations are carried out with the new Ignition-Growth reaction rate model.The RDA-2 explosive is found to have higher critical initiation pressure and lower shock sensitivity than traditional explosives(such as the Comp.B explosive).The calibrated reaction rate model parameters of RDA-2 could provide numerical basis for its further application. 展开更多
关键词 Shock initiation Ignition-growth reaction rate model Manganin pressure gauge Insensitive explosive DNAN-Based melt-cast explosive
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Androgen insensitivity syndrome: do trinucleotide repeats in androgen receptor gene have any role? 被引量:2
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作者 Singh Rajender Nalini J. Gupta +2 位作者 Baidyanath Chakravarty Lalji Singh Kumarasamy Thangaraj 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第4期616-624,共9页
Aim: To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome (AIS) phenotype. Methods: We analyzed lengths of androgen receptor (AR)-CAG and GGN repeats in ... Aim: To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome (AIS) phenotype. Methods: We analyzed lengths of androgen receptor (AR)-CAG and GGN repeats in 69 AIS cases, along with 136 unrelated normal male individuals. The lengths of repeats were analyzed using polymerase chain reaction (PCR) amplification followed by allelic genotyping to determine allele length. Results: Our study revealed significantly shorter mean lengths of CAG repeats in patients (mean 18.25 repeats, range 14-26 repeats) in comparison to the controls (mean 22.57 repeats, range 12-39 repeats) (two-tailed P 〈 0.0001). GGN repeats, however, did not differ significantly between patients (mean 21.48 repeats) and controls (mean 21.21 repeats) (two- tailed P = 0.474). Among patients' groups, the mean number of CAG repeats in partial androgen insensitivity cases (mean 15.83 repeats) was significantly less than in complete androgen insensitivity cases (mean 19.46 repeats) (two- tailed P 〈 0.0001). Conclusion: The findings suggest that shorter lengths of repeats in the AR gene might act as low penetrance genetic background in varying manifestation of androgen insensitivity. 展开更多
关键词 androgen receptor CAG repeat GGN repeat androgen insensitivity
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