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The “3 Genomic Numbers” Discovery: How Our Genome Single-Stranded DNA Sequence Is “Self-Designed” as a Numerical Whole
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作者 Jean-Claude Perez 《Applied Mathematics》 2013年第10期37-53,共17页
This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the... This article proves the existence of a hyper-precise global numerical meta-architecture unifying, structuring, binding and controlling the billion triplet codons constituting the sequence of single-stranded DNA of the entire human genome. Beyond the evolution and erratic mutations like transposons within the genome, it’s as if the memory of a fossil genome with multiple symmetries persists. This recalls the “intermingling” of information characterizing the fractal universe of chaos theory. The result leads to a balanced and perfect tuning between the masses of the two strands of the huge DNA molecule that constitute our genome. We show here how codon populations forming the single-stranded DNA sequences can constitute a critical approach to the understanding of junk DNA function. Then, we suggest revisiting certain methods published in our 2009 book “Codex Biogenesis”. In fact, we demonstrate here how the universal genetic code table is a powerful analytical filter to characterize single-stranded DNA sequences constituting chromosomes and genomes. We can then show that any genomic DNA sequence is featured by three numbers, which characterize it and its 64 codon populations with correlations greater than 99%. The number “1” is common to all sequences, expressing the second law of Chargaff. The other 2 numbers are related to each specific DNA sequence case characterizing life species. For example, the entire human genome is characterized by three remarkable numbers 1, 2, and Phi = 1.618 the golden ratio. Associated with each of these three numbers, we can match three axes of symmetry, then “imagine” a kind of hyperspace formed by these codon populations. Then we revisit the value (3-Phi)/2 which is probably universal and common to both the scale of quarks and atomic levels, balancing and tuning the whole human genome codon population. Finally, we demonstrate a new kind of duality between “form and substance” overlapping the whole human genome: we will show that—simultaneously with the duality between genes and junk DNA—there is a second layer of embedded hidden structure overlapping all the DNA of the whole human genome, dividing it into a second type of duality information/redundancy involving golden ratio proportions. 展开更多
关键词 Genetic Code CODON Populations Junk DNA Cancer Genomics Chromosomal Translocations Genomes Diversity Chromosomes Diversity WHOLE Human GENOME DNA SEQUENCE Phi the Golden Ratio Fibonacci NUMBERS Information Theory SYMMETRY Cellular Automata Chargaffs CODON Level SYMMETRY Principle Fractal Self-Similarity e Eulers Number Pi form and Substance Redundancy Encryption
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Scaling of thin wire cylindrical compression with material,diameter,and laser energy after 100 fs Joule surface heating
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作者 L.Yang M.-L.Herbert +32 位作者 C.Baehtz V.Bouffetier E.Brambrink T.Dornheim N.Fefeu T.Gawne S.Goede J.Hagemann H.Hoppner L.G.Huang O.Humphries T.Kluge D.Kraus J.Lütgert J.-P.Naedler M.Nakatsutsumi A.Pelka T.R.Preston C.B.Qu S.V.Rahul L.Randolph R.Redmer M.Rehwald J.J.Santos M.Smíd U.Schramm J.-P.Schwinkendorf M.Vescovi U.Zastrau K.Zeil A.Laso Garcia T.Toncian T.E.Cowan 《Matter and Radiation at Extremes》 2026年第1期68-80,共13页
We present the first systematic experimental validation of return-current-driven cylindrical implosion scaling in micrometer-sized Cu and Al wires irradiated by J-class femtosecond laser pulses.Employing XFEL-based im... We present the first systematic experimental validation of return-current-driven cylindrical implosion scaling in micrometer-sized Cu and Al wires irradiated by J-class femtosecond laser pulses.Employing XFEL-based imaging with sub-micrometer spatial and femtosecond temporal resolution,supported by hydrodynamic and particle-in-cell simulations,we reveal how return current density depends precisely on wire diameter,material properties,and incident laser energy.We identify deviations from simple theoretical predictions due to geometrically influenced electron escape dynamics.These results refine and confirm the scaling laws essential for predictive modeling in high-energy-density physics and inertial fusion research. 展开更多
关键词 cylindrical implosion scaling laser energy thin wire cylindrical compression MATERIAL cu al wires DIAMETER systematic experimental validation
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Use of blood-based biomarkers for early diagnosis and surveillance of colorectal cancer 被引量:11
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作者 Ganepola AP Ganepola Joel Nizin +1 位作者 John R Rutledge David H Chang 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2014年第4期83-97,共15页
Early screening for colorectal cancer(CRC) holds the key to combat and control the increasing global burden of CRC morbidity and mortality. However, the current available screening modalities are severely inadequate b... Early screening for colorectal cancer(CRC) holds the key to combat and control the increasing global burden of CRC morbidity and mortality. However, the current available screening modalities are severely inadequate because of their high cost and cumbersome preparatory procedures that ultimately lead to a low participation rate. People simply do not like to have colonoscopies. It would be ideal, therefore, to develop an alternative modality based on blood biomarkers as the first line screening test. This will allow for the differentiation of the general population from high risk individuals. Colonoscopy would then become the secondary test, to further screen the high risk segment of the population. This will encourage participation and therefore help to reach the goal of early detection and thereby reduce the anticipated increasing global CRC incidence rate. A blood-based screening test is anappealing alternative as it is non-invasive and poses minimal risk to patients. It is easy to perform, can be repeated at shorter intervals, and therefore would likely lead to a much higher participation rate. This review surveys various blood-based test strategies currently under investigation, discusses the potency of what is available, and assesses how new technology may contribute to future test design. 展开更多
关键词 Colorectal neoplasms Early detection of cancer Colonoscopy Biological markers BLOOD Messenger RNA MicroRNA Long NON-coding RNA DNA methylation Microsatellite instability Loss of HETEROZYGOSITY High-throughput NUCLEOTIDE sequencing Mass spectrometry Real-time polymerase chain reaction Microarray analysis
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The Unexpected Existence of Coding and Non-Coding Fragments along the Eukaryotic Gene
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作者 Pietro Volpe 《Advances in Biological Chemistry》 2015年第2期98-125,共28页
The pathways leading to synthesis and post-synthetic modification of DNA employed methionine as donor of atoms: the carbon that came from its –CH3 served for DNA replication and repair either in bacteria or humans;it... The pathways leading to synthesis and post-synthetic modification of DNA employed methionine as donor of atoms: the carbon that came from its –CH3 served for DNA replication and repair either in bacteria or humans;its entire –CH3 served instead for building N6-methyladenine and 5-methylcytosine on bacterial DNA and 5-methylcytosine alone on human DNA. In humans, although a slight extra-S asymmetric methylation appeared de novo yielding on parental DNA 5’-m5CpC-3’/ 3’-GpG-5’, 5’-m5CpT-3’/3’-GpA-5’ and 5’-m5CpA-3’/3’-GpT-5’ monomethylated dinucleotide pairs, a heavy symmetric methylation involved in S semiconservatively newly made DNA to guarantee genetic maintenance of –CH3 in 5’-m5CpG-3’/3’-Gpm5C-5’ dimethylated dinucleotide pairs. In this framework, an inverse correlation was found between bulk genomic DNA methylation occurring in S and bulk polyA-containing pre-mRNA transcription taking place in G1 and G2. Thus, probes of 1 × 106 Daltons (constructed using sheared by sonication newly made methylated DNA filaments) revealed a modular organization in genes: after the hypermethylated promoter, they exhibited an alternation of unmethylated coding and methylated uncoding sequences. This encouraged the search for a language that genes regulated by methylation should have in common. An initial deciphering of restriction minimaps with hypomethylatable exons vs. hypermethylatable promoters and introns was improved when the bisulfite technique allowed a direct sequencing of m5C. In lymphocytes, where the transglutaminase gene is inactive, its promoter exhibited two fully methylated CpG-rich domains at 5’ and one fully unmethylated CpG-rich domain at 3’, including the site +1 and a 5’-UTR. At variance, in HUVEC cells, where the transglutaminase gene is active, in the first CpG-rich domain of promoter few doublets lost their –CH3. Such an inverse correlation suggested new hypotheses especially in connection with repair-modification: UV radiation would cause demethylation in given loci of a promoter by chance, whilst even a partial demethylation in this promoter would be able to resume a previously silent pre-mRNA transcription. 展开更多
关键词 coding vs. NON-coding Pre-Messenger RNA Regions EXONS and INTRONS Multigenic and MONOGENIC TRANSCRIPTIONAL Units Regulation of Gene Expression Repair-Modification
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Low Bit Rate Underwater Video Image Compression and Coding Method Based on Wavelet Decomposition 被引量:3
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作者 Yonggang He Xiongzhu Bu +1 位作者 Ming Jiang Maojun Fan 《China Communications》 SCIE CSCD 2020年第9期210-219,共10页
In view of the limited bandwidth of underwater video image transmission,a low bit rate underwater video compression coding method is proposed.Based on the preprocessing process of wavelet transform and coefficient dow... In view of the limited bandwidth of underwater video image transmission,a low bit rate underwater video compression coding method is proposed.Based on the preprocessing process of wavelet transform and coefficient down-sampling,the visual redundancy of underwater image is removed and the computational coefficients and coding bits are reduced.At the same time,combined with multi-level wavelet decomposition,inter frame motion compensation,entropy coding and other methods,according to the characteristics of different types of frame image data,reduce the number of calculations and improve the coding efficiency.The experimental results show that the reconstructed image quality can meet the visual requirements,and the average compression ratio of underwater video can meet the requirements of underwater acoustic channel transmission rate. 展开更多
关键词 low bit rate DOWN-SAMPLING wavelet decomposition underwater video coding
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Compression of ECG Signals Based on DWT and Exploiting the Correlation between ECG Signal Samples
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作者 Mohammed M. Abo-Zahhad Tarik K. Abdel-Hamid Abdelfatah M. Mohamed 《International Journal of Communications, Network and System Sciences》 2014年第1期53-70,共18页
This paper presents a hybrid technique for the compression of ECG signals based on DWT and exploiting the correlation between signal samples. It incorporates Discrete Wavelet Transform (DWT), Differential Pulse Code M... This paper presents a hybrid technique for the compression of ECG signals based on DWT and exploiting the correlation between signal samples. It incorporates Discrete Wavelet Transform (DWT), Differential Pulse Code Modulation (DPCM), and run-length coding techniques for the compression of different parts of the signal;where lossless compression is adopted in clinically relevant parts and lossy compression is used in those parts that are not clinically relevant. The proposed compression algorithm begins by segmenting the ECG signal into its main components (P-waves, QRS-complexes, T-waves, U-waves and the isoelectric waves). The resulting waves are grouped into Region of Interest (RoI) and Non Region of Interest (NonRoI) parts. Consequently, lossless and lossy compression schemes are applied to the RoI and NonRoI parts respectively. Ideally we would like to compress the signal losslessly, but in many applications this is not an option. Thus, given a fixed bit budget, it makes sense to spend more bits to represent those parts of the signal that belong to a specific RoI and, thus, reconstruct them with higher fidelity, while allowing other parts to suffer larger distortion. For this purpose, the correlation between the successive samples of the RoI part is utilized by adopting DPCM approach. However the NonRoI part is compressed using DWT, thresholding and coding techniques. The wavelet transformation is used for concentrating the signal energy into a small number of transform coefficients. Compression is then achieved by selecting a subset of the most relevant coefficients which afterwards are efficiently coded. Illustrative examples are given to demonstrate thresholding based on energy packing efficiency strategy, coding of DWT coefficients and data packetizing. The performance of the proposed algorithm is tested in terms of the compression ratio and the PRD distortion metrics for the compression of 10 seconds of data extracted from records 100 and 117 of MIT-BIH database. The obtained results revealed that the proposed technique possesses higher compression ratios and lower PRD compared to the other wavelet transformation techniques. The principal advantages of the proposed approach are: 1) the deployment of different compression schemes to compress different ECG parts to reduce the correlation between consecutive signal samples;and 2) getting high compression ratios with acceptable reconstruction signal quality compared to the recently published results. 展开更多
关键词 ECG Signal Segmentation LOSSLESS and LOSSY compression Techniques Discrete Wavelet Transform Energy PACKING Efficiency RUN-LENGTH coding
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Typhoon/Hurricane/Tropical Cyclone Disasters: Prediction, Prevention and Mitigation 被引量:1
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作者 Defu Liu Fengqing Wang 《Journal of Geoscience and Environment Protection》 2019年第5期26-36,共11页
Since 1972 Rita typhoon attacked on Dalian Port and induced severe catastrophe, we were studied on statistical prediction model of typhoon induced wave height and wind speed. With an increasing tendency of the natural... Since 1972 Rita typhoon attacked on Dalian Port and induced severe catastrophe, we were studied on statistical prediction model of typhoon induced wave height and wind speed. With an increasing tendency of the natural hazards frequency and intensity, risk assessment of some design codes for coastal defence infrastructures should be of paramount importance influencing the economic development and a lot of lifes in China. Comparison between existing extreme statistical model like Gumbel, Weibull, P-III distribution or Probable Maximum Typhoon/Hurricane (PMT/PMH), Design Basis Flood (DBF) with our 1975-1980 proposed (CEVD) model showed that all the planned, designed and constructed coastal infrastructures accepted the traditional safety regulations are menaced by possibility of future ty-phoon/hurricane disasters and cannot satisfy the safety requirements with the increasing tendency of the extreme natural hazards. Our first publication in US (J. of Waterway Port Coastal & Ocean Eng. ASCE, 1980, ww4) proposed an new model “Compound Extreme Value Distribution” used for China sea, after then the model was used in “Long term Distribution of Hurricane Characteristics” for Gulf of Mexico & Atlantic coasts, U.S. (OTC.1982). 2005 hurricane Katrina, Rita and 2012 hurricane Sandy induced disasters proved 1982 CEVD and CEVD has been developed into Multivariate Compound Extreme Value Distribution (MCEVD). 2006 MCEVD predicted extreme hazards in New Orleans, Gulf of Mexico and Philadelphia areas. 2013 typhoon Fitow induced disaster in China also proved MCEVD 2006 predicted results. 展开更多
关键词 Typhoon/Hurricane Disasters: PROBABILITY PREDICTION Model Design Code Calibration Joint PROBABILITY Safety ASSESSMENT Compound and Multivariate Extreme Value Distribution Risk ASSESSMENT for Coastal Offshore and NPP Defense INFRASTRUCTURES
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An adaptive joint source and channel coding scheme for H.264 video multicasting over wireless LAN 被引量:1
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作者 LIU Zheng-ye LIU Hang WANG Yao 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期837-846,共10页
This paper proposes an adaptive joint source and channel coding scheme for H.264 video multicast over wireless LAN which takes into account the user topology changes and varying channel conditions of multiple users, a... This paper proposes an adaptive joint source and channel coding scheme for H.264 video multicast over wireless LAN which takes into account the user topology changes and varying channel conditions of multiple users, and dynamically allocates available bandwidth between source coding and channel coding, with the goal to optimize the overall system performance. In particular, source resilience and error correction are considered jointly in the scheme to achieve the optimal performance. And a channel estimation algorithm based on the average packet loss rate and the variance of packet loss rate is proposed also. Two overall performance criteria for video multicast are investigated and experimental results are presented to show the improvement obtained by the scheme. 展开更多
关键词 MULTICAST OVER 802.11 wireless local area networks (WLAN) Adaptive joint source and channel coding H.264
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A New Arithmetic Coding System Combining Source Channel Coding and MAP Decoding
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作者 逄玉叶 孙军 王嘉 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第4期442-447,共6页
A new arithmetic coding system combining source channel coding and maximum a posteriori decoding were proposed. It combines source coding and error correction tasks into one unified process by introducing an adaptive ... A new arithmetic coding system combining source channel coding and maximum a posteriori decoding were proposed. It combines source coding and error correction tasks into one unified process by introducing an adaptive forbidden symbol. The proposed system achieves fixed length code words by adaptively adjusting the probability of the forbidden symbol and adding tail digits of variable length. The corresponding improved MAP decoding metric was derived. The proposed system can improve the performance. Simulations were performed on AWGN channels with various noise levels by using both hard and soft decision with BPSK modulation.The results show its performance is slightly better than that of our adaptive arithmetic error correcting coding system using a forbidden symbol. 展开更多
关键词 ARITHMETIC code (AC) forbidden SYMBOL joint SOURCE channel coding (JSCC) MAXIMUM a POSTERIORI (MAP) DEcoding
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DESIGN AND PERFORMANCE OF SYMBOL/SEQUENCE TCM FOR DS/SSMA SYSTEM OVER MOBILE RADIO CHANNEL
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作者 仰枫帆 毕光国 许宗泽 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期26-32,共7页
A novel kind of multidimension symbol/sequence trellis coded modulation (TCM) based on TCM of lower coding rate has been constructed. The redundancy of this new kind of TCM is provided not only by the modulated symbo... A novel kind of multidimension symbol/sequence trellis coded modulation (TCM) based on TCM of lower coding rate has been constructed. The redundancy of this new kind of TCM is provided not only by the modulated symbol sequence but also by the PN sequences for spreading spectrum as well. The performance of direct sequence spread spectrum multiple access (DS/SSMA) system with this symbol/sequence TCM over flat Rayleigh fading channel has been investigated by theoretical analysis and numerical simulation. The results obtained in this research demonstrate the performance improvements of this system in comparison with that of the DS/SSMA system with conventional TCM under the same conditions. 展开更多
关键词 TRELLIS coded modulation direct SEQUENCE spread spectrun multiple access RAYLEIGH fading channel MAXIMAL LIKELIHOOD decaling probability of bit error rate
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Intermittent Pneumatic Compression in Treatment of Chronic Venous Leg Ulcers: A Case Report and Review of Literature
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作者 Ali Kordzadeh Attila Jonas Yiannis P. Panayiotopoulos 《Case Reports in Clinical Medicine》 2014年第9期513-517,共5页
Introduction: The benefit of intermittent pneumatic compression (IPC) for the prevention of venous thromboembolism and lymphedema has been well established in the literature. Recent evidence suggests that IPC plays a ... Introduction: The benefit of intermittent pneumatic compression (IPC) for the prevention of venous thromboembolism and lymphedema has been well established in the literature. Recent evidence suggests that IPC plays a beneficial role in circulation, hemodynamic peripheral pump, intravascular coagulation and arterial skin perfusion. Despite such evidence, the use of IPC in the treatment of resistant and chronic venous leg ulcers, has received little attention in practice. Case Presentation: We would like to report the case of successfully treated chronic and bilateral venous leg ulcer in an obese patient with IPC application and a review of the literature. Results: The use of IPC as an adjuvant therapy to the traditional multilayered compression therapy permitted significant resolution of the ulcers, reduced secondary infection incidence and prevented ulcer recurrence. Conclusion: In obese, minimally mobile patients with venous ulcers not responding to the traditional multilayered compression therapy application of IPC, an adjuvant therapy is recommended. 展开更多
关键词 Intermittent Pneumatic compression (IPC) CHRONIC VENOUS LEG ULCERS Bilateral VENOUS LEG ULCER Management compression Therapy OBESE Patient Follow-Up
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A reduced computational load protein coding predictor using equivalent amino acid sequence of DNA string with period-3 based time and frequency domain analysis 被引量:1
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作者 Jayakishan K. Meher Gananath N. Dash +1 位作者 Pramod Kumar Meher Mukesh Kumar Raval 《American Journal of Molecular Biology》 2011年第2期79-86,共8页
Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein codi... Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction. 展开更多
关键词 GENOMICS Bioinformatics CODON coding region Amino Acid SEQUENCE Fourier Transform Antinotch Filter Periodicity-3 Indicator SEQUENCE
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Minimally Invasive Open Reduction and Internal Fixation for Osteoporotic Vertebral Compression Fractures: Technical Report and Mid-Term Outcomes 被引量:1
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作者 Jui-Yang Hsieh Po-Quang Chen Jyh-Horng Wang 《Open Journal of Orthopedics》 2018年第9期337-350,共14页
Background: Traditional open instrumentation may cause surgical complications due to fragile bones and induce medical comorbidities in senile patients. Vertebroplasty and kyphoplasty are palliative augmentation proced... Background: Traditional open instrumentation may cause surgical complications due to fragile bones and induce medical comorbidities in senile patients. Vertebroplasty and kyphoplasty are palliative augmentation procedures that have been associated with increased risks of cement leakage, adjacent fractures and non-union. Objective: The aim of this study was to describe a novel approach for the union of osteoporotic vertebral compression fractures with minimally invasive open reduction and internal fixation. Patients and Methods: Seven consecutive patients with intractable back pain without neurological deficits due to osteoporotic vertebral compression fractures were treated using minimally invasive fixation with intra-vertebral expandable pillars and artificial bone substitute. The clinical symptoms and image findings were recorded. Results: All of the patients reported relief of back pain, and the height of the vertebral bodies was well restored. X-ray findings obtained 2 to 4 years after the procedures showed fracture healing and favorable formation of the callus confirmed in the anterior longitudinal ligament. Conclusion: This mini-open procedure with intravertebral devices is an effective and reliable technique for osteoporotic vertebral compression fractures and may avoid complications related to traditional open spinal instrumentation procedures and augmentation with bone cement. 展开更多
关键词 OSTEOPOROTIC VERTEBRAL compression FRACTURE MINIMALLY Invasive Spine Surgery Intra-Vertebral EXPandABLE PILLAR FRACTURE Union Bone Cement
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Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors 被引量:22
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作者 Orsolya Galamb Barbara K Barták +5 位作者 Alexandra Kalmár Zsófia B Nagy Krisztina A Szigeti Zsolt Tulassay Peter Igaz Béla Molnár 《World Journal of Gastroenterology》 SCIE CAS 2019年第34期5026-5048,共23页
Long non-coding RNAs(lncRNAs)are members of the non-protein coding RNA family longer than 200 nucleotides.They participate in the regulation of gene and protein expression influencing apoptosis,cell proliferation and ... Long non-coding RNAs(lncRNAs)are members of the non-protein coding RNA family longer than 200 nucleotides.They participate in the regulation of gene and protein expression influencing apoptosis,cell proliferation and immune responses,thereby playing a critical role in the development and progression of various cancers,including colorectal cancer(CRC).As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality,its screening and early detection are crucial,so the identification of disease-specific biomarkers is necessary.LncRNAs are promising candidates as they are involved in carcinogenesis,and certain lncRNAs(e.g.,CCAT1,CRNDE,CRCAL1-4)show altered expression in adenomas,making them potential early diagnostic markers.In addition to being useful as tissue-specific markers,analysis of circulating lncRNAs(e.g.,CCAT1,CCAT2,BLACAT1,CRNDE,NEAT1,UCA1)in peripheral blood offers the possibility to establish minimally invasive,liquid biopsy-based diagnostic tests.This review article aims to describe the origin,structure,and functions of lncRNAs and to discuss their contribution to CRC development.Moreover,our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC. 展开更多
关键词 Long NON-coding RNA COLORECTAL cancer COLORECTAL adenoma CIRCULATING long NON-coding RNAs Exosome Biomarker DIAGNOSTIC MARKER PROGNOSTIC MARKER
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Design of an adaptive precoding/STBC baseband transceiver on a reconfigurable architecture
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作者 Ye Yunfei Wu Ning +1 位作者 Ge Fen Zhou Fang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期266-272,共7页
Precoding and space-time block coding (STBC)techniques using the uniform channel decomposition (UCD)are proposed to improve the bit error rate (BER) of themultiple-antenna communication system, but at a cost of ... Precoding and space-time block coding (STBC)techniques using the uniform channel decomposition (UCD)are proposed to improve the bit error rate (BER) of themultiple-antenna communication system, but at a cost of areduced data rate. In order to achieve a higher overall systemperformance, a novel adaptive transceiver architecture whichflexibly combines both UCD and UCD + STBC technologies isproposed. The channel state information (CSI) feedback pathwas added to the precoder to select which coding method wasto be used, i.e. UCD alone or UCD + STBC. With thesmaller constellation sizes, Matlab simulation results showthat, the adaptive transceiver architecture will select the UCD-only mode under the higher SNR conditions in order to achievea higher bit rate. The UCD + STBC mode will be selectedunder the lower SNR conditions (e. g., SNR 〈 10 dB) inorder to maintain good BER performance at the cost of areduced data rate. This architecture was implemented andverified using both UMC 0.18 ASIC process technology and aXilinx xc4vlx Virtex-4 FPGA at 150 MHz. The simulationresults demonstrate that the required number of reconfigurablearithmetic unit slices grows linearly with the channel matrixsize, while the number of adder array unit and reconfigurablelogic unit slices increases slightly with the constellation size. 展开更多
关键词 PREcoding uniform channel decomposition (UCD) space-time block coding (STBC) ADAPTIVE transceiver reconfigurable BASEBand architecture
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Cross-layer design of combining AMC with HARQ in cooperative relay system with perfect and imperfect CSI
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作者 唐伦 张荣荣 陈前斌 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第4期118-128,共11页
A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay syst... A cross-layer design which combines adaptive modulation and coding (AMC) at the physical layer with a hybrid automatic repeat request (HARQ) protocol at the data link layer (LL) is presented, in cooperative relay system over Nakagami-m fading channels with perfect and imperfect channel state information (CSI). In order to maximize spectral efficiency (SE) under delay and packet error rate (PER) performance constraints, a state transition model and an optimization framework with perfect CSI are presented. Then the framework is extended to cooperative relay system with imperfect CSI. The numerical results show that the scheme can achieve maximum SE while satisfying transmitting delay requirements. Compared with the imperfect CSI, the average PER with perfect CSI is much lower and the spectral efficiency is much higher. 展开更多
关键词 COOPERATIVE relay system cross-layer design and optimization adaptive modulation and coding (AMC) hybrid automatic REPEAT request (HARQ) PERFECT channel state information(CSI) imperfect CSI
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Experiments and 3D DEM of Triaxial Compression Tests under Special Consideration of Particle Stiffness
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作者 Marx Ferdinand Ahlinhan Ernesto Houehanou +4 位作者 Marius Bocco Koube Valery Doko Quirin Alaye Nicholas Sungura Edmond Adjovi 《Geomaterials》 2018年第4期39-62,共24页
Discrete element modelling is commonly used for particle-scale modelling of granular or particulate materials. Developing a DEM model requires the determination of a number of micro-structural parameters, including th... Discrete element modelling is commonly used for particle-scale modelling of granular or particulate materials. Developing a DEM model requires the determination of a number of micro-structural parameters, including the particle contact stiffness and the particle-particle friction. These parameters cannot easily be measured in the laboratory or directly related to measurable, physical material parameters. Therefore, a calibration process is typically used to determine the values for use in simulations of physical systems. This paper focuses on how to define the particle stiffness for the discrete element modelling in order to perform realistic simulations of granular materials in the case of linear contact model. For that, laboratory tests and numerical discrete element modelling of triaxial compression tests have been carried out on two different non-cohesive soils i.e. poorly graded fine sand and gap graded coarse sand. The results of experimental tests are used to calibrate the numerical model. It is found that the numerical results are qualitatively and quantitatively in good agreement with the laboratory tests results. Moreover, the results show that the stress dependent of soil behaviour can be reproduced well by assigning the particle stiffness as a function of the particle size particularly for gap graded soil. 展开更多
关键词 GRAIN Size Dependent STIFFNESS Experiment Discrete Element Modelling TRIAXIAL compression Test Non-Cohesive SOILS Materials
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Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)
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作者 Peh Keong TEH Seyed ZEKAVAT 《International Journal of Communications, Network and System Sciences》 2009年第6期469-479,共11页
In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (a... In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas. 展开更多
关键词 Antenna Array Beam Pattern SWEEPING Transmit Diversity SPACE-TIME Block CODES and SPACE-TIME TRELLIS coding
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Modeling and Simulation of CDMA Codes in Scilab
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作者 Mouhamed Fadel Diagana Serigne Bira Gueye 《International Journal of Communications, Network and System Sciences》 2015年第7期274-281,共8页
Prior to hardware implementation, simulation is an important step in the study of systems such as Direct Sequence Code Division Multiple Access (DS-CDMA). A useful technique is presented, allowing to model and simulat... Prior to hardware implementation, simulation is an important step in the study of systems such as Direct Sequence Code Division Multiple Access (DS-CDMA). A useful technique is presented, allowing to model and simulate Linear Feedback Shift Register (LFSR) for CDMA. It uses the Scilab package and its modeling tool for dynamical systems Xcos. PN-Generators are designed for the quadrature-phase modulation and the Gold Code Generator for Global Positioning System (GPS). This study gives a great flexibility in the conception of LFSR and the analysis of Maximum Length Sequences (MLS) used by spread spectrum systems. Interesting results have been obtained, which allow the verification of generated sequences and their exploitation by signal processing tools. 展开更多
关键词 Code Division Multiple Access (CDMA) Linear Feedback Shift Register (LFSR) Maximum Length SEQUENCE (MLS) SPREAD-SPECTRUM SCILAB Xcos Direct SEQUENCE Spread Spectrum (DSSS)
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Low-Velocity Impact and Compression after Impact(CAI)Behaviors of Carbon-Aramid/Epoxy Hybrid Braided Composite Laminates
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作者 CAO Hongxue SUN Ying +2 位作者 TANG Mengyun DING Xu CHEN Li 《Journal of Donghua University(English Edition)》 EI CAS 2020年第1期17-27,共11页
Low-velocity impact and in-plane axial compression after impact(CAI)behaviors of carbon-aramid/epoxy hybrid braided composite laminates were investigated experimentally.The following three different types of carbon-ar... Low-velocity impact and in-plane axial compression after impact(CAI)behaviors of carbon-aramid/epoxy hybrid braided composite laminates were investigated experimentally.The following three different types of carbon-aramid/epoxy hybrid braided composite laminates were produced and tested:(a)inter-hybrid laminates,(b)sandwich-like inter-hybrid laminates,and(c)unsymmetric-hybrid laminates.At the same time,carbon/epoxy braided composite laminates were used for comparisons.Impact properties and impact resistance were studied.Internal damages and damage mechanisms of laminates were detected by ultrasonic C-scan and B-scan methods.The results show that the ductility index(DI)values of three kinds of hybrid laminates aforementioned are 37%,4%and 120%higher than those of carbon/epoxy laminates,respectively.The peak load of inter-hybrid laminates is higher than that of sandwich-like inter-hybrid laminates and unsymmetric-hybrid laminates.The average damage area and dent depths of inter-hybrid laminates are 64%and 69%smaller than those of carbon/epoxy laminates.Those results show that carbon-aramid/epoxy hybrid braided composite laminates could significantly improve the impact properties and toughness of non-hybrid braided composite laminates. 展开更多
关键词 COMPOSITE braided COMPOSITE carbon/epoxy carbon-aramid/epoxy hybrid laminated COMPOSITE low-velocity IMPACT in-plane axial compression compression after impact(CAI)
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