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Polypeptide analysis for nanopore-based protein identification

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Nano Research 2022年第11期15卷 9831-9842页

作者： Mazdak Afshar Bakshloo safia Yahiaoui Fabien Piguet Manuela Pastoriza-Gallego Régis Daniel Jérôme Mathé John J.Kasianowicz Abdelghani Oukhaled CY Cergy Paris Université CNRSLAMBE95000CergyFrance UniversitéParis-Saclay Univ EvryCNRSLAMBE91025Evry-CourcouronnesFrance University of South Florida Dept.of PhysicsTampaFL 33620USA Freiburg Institute for Advanced Studies Universität FreiburgFreiburg 79104Germany

Presently,proteins are identified by cleaving them with proteases,measuring the mass to charge ratio of the fragments with a mass spectrometer,and matching the fragments to segments within known proteins in *** earlier demonstrated that a nanometer-scale pore formed by aerolysin(AeL)can discriminate between,and therefore identify,three similar size proteins from their trypsin-cleaved polypeptide *** this nanopore-protease method,the protein’s identity is instead determined from characteristic ionic current blockade patterns caused by the polypeptide fragments that enter the *** results also suggested that not all of the theoretically expected cleavage products partition into the *** better understand the mechanism by which polypeptide fragments are captured,and how different polypeptides reduce the pore’s ionic current,we studied the effects of 11 identical length polypeptides with different net charges and charge *** show that under certain experimental conditions,negative,positive,and neutral polypeptides are driven into the AeL pore by the same applied voltage *** capture rate and dwell time of polypeptides in the pore depend strongly on the ionic strength,the magnitude of the applied voltage,and the net charge and charge distribution of the *** dwell time distribution depends nonmonotonically on the applied voltage(regardless of the polymer’s net charge),and its maximum value depends on the polypeptide net charge and charge *** maximum dwell time for different polypeptides does not occur at the same applied voltage amplitude,which conceivably might complicate the detection and discrimination of some polypeptide *** additional experiments,computer simulations,and artificial intelligence research are needed to better understand how to optimize the partitioning of enzymatically cleaved fragments into the AeL nanopore,the method is still capable of accurately identifying

关键词： protein identification nanopores trypsin enzymatic degradation

Enhanced Fingerprinting Based Indoor Positioning Using Machine Learning

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Computers, Materials & Continua 2021年第11期69卷 1631-1652页

作者： Muhammad Waleed Pasha Mir Yasir Umair Alina Mirza Faizan Rao Abdul Wakeel safia Akram Fazli Subhan Wazir Zada Khan Department of Electrical Engineering National University of Sciences and TechnologyIslamabad44000Pakistan Department of Computer Engineering National University of Modern Languages(NUML)Islamabad44000Pakistan Faculty of Computing Capital University of Science and TechnologyIslamabad44000Pakistan

Due to the inability of the Global Positioning System(GPS)signals to penetrate through surfaces like roofs,walls,and other objects in indoor environments,numerous alternative methods for user positioning have been *** those,the Wi-Fi fingerprinting method has gained considerable interest in Indoor Positioning Systems(IPS)as the need for lineof-sight measurements is minimal,and it achieves better efficiency in even complex indoor *** and online are the two phases of the fingerprinting *** researchers have highlighted the problems in the offline phase as it deals with huge datasets and validation of Fingerprints without pre-processing of data becomes a *** learning is used for the model training in the offline phase while the locations are estimated in the online *** researchers have considered the concerns in the offline phase as it deals with huge datasets and validation of Fingerprints becomes an *** learning algorithms are a natural solution for winnowing through large datasets and determining the significant fragments of information for localization,creating precise models to predict an indoor *** training sets are a key for obtaining better results in machine learning ***,an existing WLAN fingerprinting-based multistory building location database has been used with 21049 samples including 19938 training and 1111 testing *** proposed model consists of mean and median filtering as pre-processing techniques applied to the database for enhancing the accuracy by mitigating the impact of environmental dispersion and investigated machine learning algorithms(kNN,WkNN,FSkNN,and SVM)for estimating the *** proposed SVM with median filtering algorithm gives a reduced mean positioning error of 0.7959 m and an improved efficiency of 92.84%as compared to all variants of the proposed method for 108703 m^(2) area.

关键词： Indoor positioning system fingerprinting received signal strength indicator mean position error support vector machine

The Prospect of Ethical Consulting

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Journal of Modern Accounting and Auditing 2014年第10期10卷 1021-1029页

作者： Luu Yin safia Wemah University for Development Studies Navrongo Ghana University for Development Studies Tamale Ghana

Ethical consulting is a critical professional activity that is very critical to the very survival of the corporate world and is thus likely to boom within the shortest possible time in the future. This predictive statement is based on the consequential effect of the bankruptcy of Ertron and WorldCom and its aftermath legislature, Sarbanes-Oxley Act （Lander, 2004）. The main issues boarder on how ethics influence organizations＇ operations and to what extend these influences can be coded and managed to enhance objectivity and minimize fraud. The methodology applied in this paper was an exploratory approach under the qualitative design. It encapsulates a thorough review of literature on the subject matter and draws inferences to address the research objectives. It was found that ethical consulting was possible and consultants venturing into the area need to be strategically diversified to enable them to design and develop customized ethical codes for the heterogeneous clientele with appropriate supporting monitoring and compliance procedures.

关键词： ethics compliance gatekeeper consultancy

多种信号途径介导花生四烯酸与5-羟色胺在促人类血小板凝集中的协同作用(英文)

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Acta Pharmacologica Sinica 2003年第10期24卷 8-14+110页

作者： Sheikh Arshad SAEED,Huma RASHEED,Anwar-ul-Hassan gilani Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan

AIM: To examine the signalling mechanisms involved in the synergistic interaction of 5-hydroxytryptamine （5-HT） and arachidonic acid （AA） in human platelet aggregation. METHODS: Blood was obtained from healthy human subjects, mixed with 3.8% sodium citrate （9:1）, and centrifuged to prepare platelet rich plasma （PRP）. Aggregation was monitored using a Dual-channel Lumi-aggregometer. The agonist-induced influx of Ca2+was measured using Fura-2 AM. TXA2formation was studied using radiochemical method. RESULTS: Subthreshold concentration of 5-HT （2μmol/L） potentiated the effect of low dose of AA （0.2 mmol/L） in human platelets. This synergistic effect was blocked by 5-HT2receptor antagonist (methysergide IC50=5.2 nmol/L; cyproheptadine IC50=0.6 nmol/L), and thromboxane A2receptor antagonist (SQ 29 548; IC50=30 nmol/L), showing that the effect is receptor-mediated. To examine the down-stream signalling pathways, we found that such an interaction was inhibited by calcium channel blockers (d

关键词：血清素花生四烯酸类血小板聚集环氧化酶抑制剂美舍吉特塞庚啶血栓烷A2 磷脂酶C 钙药物协同作用

Radiological Effectual and Mineral Salts Measurements of Sandstone Used in the Construction from Al Wajh, Al Ula and North Al Ula, Az Zabirah-Saudi Arabia

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Journal of Geoscience and Environment Protection 2022年第9期10卷 84-95页

作者： safia H. Q. Hamidalddin Physics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

The activity concentrations of natural radionuclides 226Ra, 232Th and 40K, were measured in (16) sandstone samples collected from two regions of Saudi Arabia, Region 1 (Al Wajh on Red Sea coast and Al Ula north-East of Medina), Region 2 (North of Al Ula and Az Zabirah, North-West of Hail) by (HPGe gamma spectrometer). The activity concentration average values of the radionuclides 226Ra, 232Th, and 40K in the sandstone samples (Region 1) ranged from 10.97 ± 0.43, 27.68 ± 0.37 and 64.56 ± 0.74 Bq/kg respectively. These values are less than the international values reported by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2000), in (Region 2), average values ranged from 2465.49 ± 0.00, 2042.00 ± 0.00 and 2259.65 ± 0.64 Bq/kg respectively. These values are higher than the values reported by (UNSCEAR, 2000). Average values of radium equivalent activity Raeq (Bq/Kg), absorbed dose rate D (nGy/h), annual effective radiation dose Deff (mSv/y), External index (Hex) and Internal index (Hin) were in (region 1) 21.13, 27.22, 11.75, 0.07 and 0.10 respectively, in (region 2) 5775.19, 1787.78, 846.58, 11.57 and 15.64 respectively. These results are lower (except annual effective radiation dose) in (region 1) and higher in (region 2) than the world recommended values by (UNSCEAR, 2000). Also, samples were analyzed by Atomic Absorption spectrometer (AAS) for Al, Ca, Fe, K, Mg and Bi in % elements concentrations. Average value in (region 1) (Al Wajh and Al Ula) are 4.42, 0.41, 1.37, 0.04 and 0.03, (in region 2) (N. Al Ula and Az Zabirah) are 12.50, 10.05, 1.01, 1.19, 0.04 respectively. Classifications of sandstone depend on the content of these elements. These results are important for the safety of dwellers and user of sandstone in constructions.

关键词： Gamma Spectrometer AA Spectrometer Natural Radioactivity Chemical Elements

A Study of Chemical, Mineral Compositions (of Some Metals) and Natural Radioactivity in Porcelain and Ceramic Dinner Ware

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Journal of Geoscience and Environment Protection 2020年第11期8卷 209-221页

作者： safia H. Q. Hamidalddin Physics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

Fifteen Porcelain and Ceramic Dinner Wares samples (collected from local commercial suppliers—Jeddah Saudi Arabia) were studied applying X-Ray Diffraction and Atomic Absorption techniques were used to study the Chemical, Mineral, Compositions Concentrations (of Some Metals). In addition, the Natural Radioactivity measurements of 226Ra, 232Th and 40K, was used by a high-purity germanium (HPGe) detector. X-ray diffraction results showed that the major mineral constituents of 15 samples were quartz (SiO2) (except one), minor and trace elements vary from sample to sample. Atomic absorption spectroscopy results of the concentrations for (Al, Pb, Bi, U, Th and K) in (ppm) showed that Al2O average was 10.3 (ppm) (10%) less than the acceptable value. PbO, its average was 1.65 ppm which was slightly greater than the allowed value 1.35 ppm. Bi concentrations for all samples were lower than (DL 238U, 232Th and 40 K were (83.83, 91.05 and 751.07) Bq/kg dry. The radium equivalent activity concentration Raeq (Bq/kg) (302.61) was less than recommended value (370), gamma dose rate D (nGy/h) average (140.15) was much higher than the recommended value (60) (UNSCEER). Deff (mSv/year) and Hix were below the published admissible limit ≤ 1 and the risk is negligible. This study offers needed information for consumers at exposure risk and is useful to be found in terms of radiation protection.

关键词： X-Ray Diffraction Atomic Absorption Gamma-Ray Spectroscopy Natural Radioactivity Dinnerware

60 Golden Years of New China

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Voice of Friendship 2009年第Z1期 21-24页

作者： Syed Ali Nawaz gilani

Today is October 1, 2009, a day of joy and happiness for the People’s Republic of China and friends of China around the world to mark the 60th founding anniversary of the People’s Republic. In the past 60 years

关键词： Golden founding happiness friends Republic diploma

CITIUS,ALTIUS,FORTIUS…BEIJING

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Voice of Friendship 2008年第5期 9-10,7页

作者： Syed Ali Nawaz gilani

The dawn of August 8th, 2008 will witness thegr and opening ceremony of the 29th Olympics in Beijing. The world’s most prestigious mega sporting event where athletes & delegations from

关键词： Olympics ceremony witness BEIJING party sports qua

Improving the Texture Spectrum Model Using a Compact Texture Unit Descriptor

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通讯和计算机（中英文版） 2013年第2期10卷 234-251页

作者： Abdelmounaime safia Dong-Chen He Centre for Research and Applications in Remote Sensing Sherbrooke University Sherbrooke 2500 Canada