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Real time endoscopic ultrasound elastography and strain ratio in the diagnosis of solid pancreatic lesions

World Journal of Gastroenterology 2017年第32期23卷 5962-5968页

作者： Hussein Okasha Shaimaa elkholy Ramy el-Sayed Mohamed-Naguib Wifi Mohamed el-Nady walid el-nabawi Waleed A el-Dayem Mohamed I Radwan Ali Farag Yahya el-sherif Emad Al-Gemeie Ahmed Salman Mohamed el-Sherbiny Ahmed el-Mazny Reem E Mahdy Internal Medicine Department Cairo University Department of Tropical Medicine Zagazig University Internal Medicine Department Beni Suef University Tropical Medicine Department El Manial Specialized Hospital Pathology Department National Cancer InstituteCairo University Internal Medicine Department Assiut University

AIM To evaluate the accuracy of the elastography score combined to the strain ratio in the diagnosis of solid pancreatic lesions(SPL). METHODS A total of 172 patients with SPL identified by endoscopic ultrasound were enrolled in the study to evaluate the efficacy of elastography and strain ratio in differentiating malignant from benign lesions. The semi quantitative score of elastography was represented by the strain ratio method. Two areas were selected, area(A) representing the region of interest and area(B) representing the normal area. Area(B) was then divided by area(A). Sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV), and accuracy were calculated by comparing diagnoses made by elastography, strain ratio and final *** SPL were shown to be benign in 49 patients and malignant in 123 patients. elastography alone had a sensitivity of 99%, a specificity of 63%, and an accuracy of 88%, a PPV of 87% and an NPV of 96%. The best cut-off level of strain ratio to obtain the maximal area under the curve was 7.8 with a sensitivity of 92%, specificity of 77%, PPV of 91%, NPV of 80% and an accuracy of 88%. Another estimated cut off strain ratio level of 3.8 had a higher sensitivity of 99% and NPV of 96%, but with less specificity, PPV and accuracy 53%, 84% and 86%, respectively. Adding both elastography to strain ratio resulted in a sensitivity of 98%, specificity of 77%, PPV of 91%, NPV of 95% and accuracy of 92% for the diagnosis of SPL. CONCLUSION Combining elastography to strain ratio increases the accuracy of the differentiation of benign from malignant SPL.

关键词： Endoscopic Ultrasound elastography Strain Ratio Real Time Pancreatic lesions

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A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa F.Soliman Fatma E.Fadl-Allah walid el-Shafai Mahmoud I.Aly Maali Alabdulhafith Fathi E.Abd el-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of electronics and electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier Frequency Division Multiple Access(SC-FDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-FDMA systemas an adopted communication *** introduces a robust image communication framework over SC-FDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-FDMA *** linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-FDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

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Assessment of vegetation cover changes and the contributing factors in the Al-Ahsa Oasis using Normalized Difference Vegetation Index(NDVI)

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Regional Sustainability 2024年第1期5卷 42-53页

作者： walid CHOUARI Department of Geography College of ArtsKing Faisal UniversityAl-Ahsa31982Saudi Arabia Laboratory Syfacte Faculty of Arts and Humanities of SfaxUniversity of SfaxSfax1168-3000Tunisia

The abandonment of date palm grove of the former Al-Ahsa Oasis in the eastern region of Saudi Arabia has resulted in the conversion of delicate agricultural area into urban *** current state of the oasis is influenced by both expansion and degradation ***,it is important to study the spatiotemporal variation of vegetation cover for the sustainable management of oasis *** study used Landsat satellite images in 1987,2002,and 2021 to monitor the spatiotemporal variation of vegetation cover in the Al-Ahsa Oasis,applied multi-temporal Normalized Difference Vegetation Index(NDVI)data spanning from 1987 to 2021 to assess environmental and spatiotemporal variations that have occurred in the Al-Ahsa Oasis,and investigated the factors influencing these *** study reveals that there is a significant improvement in the ecological environment of the oasis during 1987–2021,with increase of NDVI values being higher than *** 2021,the highest NDVI value is generally above 0.70,while the lowest value remains largely ***,there is a remarkable increase in NDVI values between 0.20 and *** area of low NDVI values(0.00–0.20)has remained almost stable,but the region with high NDVI values(above 0.70)expands during 1987–***,this study finds that in 1987–2002,the increase of vegetation cover is most notable in the northern region of the study area,whereas from 2002 to 2021,the increase of vegetation cover is mainly concentrated in the northern and southern regions of the study *** 1987 to 2021,NDVI values exhibit the most pronounced variation,with a significant increase in the“green”zone(characterized by NDVI values exceeding 0.40),indicating a substantial enhancement in the ecological environment of the *** NDVI classification is validated through 50 ground validation points in the study area,demonstrating a mean accuracy of 92.00%in the detection of vegetation *** general,both the user’s and produce

关键词： Normalized Difference Vegetation Index(NDVI) Vegetation cover Ecological environment Land use and land cover(LULC) Urban expansion Al-Ahsa Oasis

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Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance

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Chinese Journal of Chemical Engineering 2024年第4期68卷 241-252页

作者： Yunyu Guo Yiran Wang Shu Zhang Yi Wang Song Hu Jun Xiang walid Nabgan Xun Hu School of Material Science and Engineering University of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China Departament d'Enginyeria Química Universitat Rovira i VirgiliTarragona 43007Spain

Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic ***,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam *** results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic *** converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high *** high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts.

关键词： Steam reforming Acetic acid Ni/biochar catalyst Property of coke Reaction intermediates

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Soil erosion susceptibility mapping of Hangu Region,Kohat Plateau of Pakistan using GIS and RS-based models

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Journal of Mountain Science 2024年第8期21卷 2547-2561页

作者： Fakhrul ISLAM Liaqat Ali WASEEM Tehmina BIBI Waqar AHMAD Muhammad SADIQ Matee ULLAH walid SOUFAN Aqil TARIQ Department of Geology Khushal Khan Khattak UniversityKarak 27200Pakistan Department of Geography Government College University FaisalabadPunjab 38000Pakistan Institute of Geology The University of Azad Jammu&KashmirMuzaffarabad 13100Pakistan Department of Earth Sciences Changan UniversityXi’an 710003China NCEG University of PeshawarPeshawar 25120Pakistan Faculty of Earth Sciences Geography and AstronomyUniversity of ViennaVienna 1090Austria Plant Production Department College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia Department of Wildlife Fisheries and AquacultureCollege of Forest ResourcesMississippi State UniversityMS 39762USA

Soil erosion is a crucial geo-environmental hazard worldwide that affects water quality and agriculture,decreases reservoir storage capacity due to sedimentation,and increases the danger of flooding and ***,this study uses geospatial modeling to produce soil erosion susceptibility maps(SESM)for the Hangu region,Khyber Pakhtunkhwa(KPK),*** Hangu region,located in the Kohat Plateau of KPK,Pakistan,is particularly susceptible to soil erosion due to its unique geomorphological and climatic ***,the Hangu region is characterized by a combination of steep slopes,variable rainfall patterns,diverse land use,and distinct soil types,all of which contribute to the complexity and severity of soil erosion *** factors necessitate a detailed and region-specific study to develop effective soil conservation *** this research,we detected and mapped 1013 soil erosion points and prepared 12 predisposing factors(elevation,aspect,slope,Normalized Differentiate Vegetation Index(NDVI),drainage network,curvature,Land Use Land Cover(LULC),rainfall,lithology,contour,soil texture,and road network)of soil erosion using GIS ***,GIS-based statistical models like the weight of evidence(WOE)and frequency ratio(FR)were applied to produce the SESM for the study *** SESM was reclassified into four classes,i.e.,low,medium,high,and very high *** results of WOE for SESM show that 16.39%,33.02%,29.27%,and 21.30%of areas are covered by low,medium,high,and very high zones,*** contrast,the FR results revealed that 16.50%,24.33%,35.55%,and 23.59%of the areas are occupied by low,medium,high,and very high ***,the reliability of applied models was evaluated using the Area Under Curve(AUC)*** validation results utilizing the area under curve showed that the success rate curve(SRC)and predicted rate curve(PRC)for WOE are 82%and 86%,respectively,while SRC and PRC for FR are 85%and 96%,res

关键词： Soil erosion Geospatial technology Statistical models Hangu Pakistan

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