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Improved reversed phase liquid chromatographic method with pulsed electrochemical detection for tobramycin in bulk and pharmaceutical formulation

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Journal of Pharmaceutical Analysis 2013年第3期3卷 161-167页

作者： Vicky Manyanga Ehab Elkady Jos Hoogmartens Erwin adams Laboratory for Pharmaceutical Analysis Faculteit Farmaceutische Wetenschappen KU LeuvenO&N2 PB 923 Herestraat 49 B-3000 Leuven Belgium Pharmaceutical Chemistry Department Faculty of Pharmacy Cairo University Kasr El-Aini St.Cairo 11562 Egypt

Tobramycin is one of the aminoglycoside antibiotics that lack a UV absorbing chromophore. However, the application of pulsed electrochemical detection （PED） has been used successfully for the analysis of this and similar antibiotics. This work describes an improved liquid chromatographic （LC） method combined with PED, which is able to separate much more impurities than before. Using a Discovery C-18 RP column （250 mm × 4.6 mm i.d., 5 μm）, isocratic elution was carried out with a mobile phase, containing sodium sulfate （35 g/L）, sodium octanesulphonic acid （1 g/L）, tetrahydrofuran （14mL/L） and 0.2 M phosphate buffer pH 3.0 （50 mL/L）. Using these experimental conditions, the limit of quantification （LOQ, S/N= 10） was 5 ng. The linearity was examined in the range LOQ-60 μg/mL and the coefficient of determination was 0.998. The method also proved to be repeatable and the recovery was close to 100%. The influence of the different chromatographic parameters on the separation was investigated by means of an experimental design. The proposed method is useful in quality control of tobramycin drug substances and drug products.

关键词： Liquidchromatography-Pulsed electrochemicaldetection Tobramycin Aminoglycosideantibiotics

Vertical Cavity Semiconductor Optical Amplifiers:Physics and Applications

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光学学报 2003年第S1期23卷 449-450页

作者： M J adams D Alexandropoulos G Dubois A Dyson Department of Electronic Systems Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UKDepartment of Electronic Systems Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UKDepartment of Electronic Systems Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UKDepartment of Electronic Systems Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UK

A review is presented of the state-of-the-art in vertical cavity semiconductor optical amplifiers (VCSOAs), focusing in particular on recent developments in theoretical analysis, wavelengths of operation, materials sy... 详细信息

关键词： been it on Vertical Cavity Semiconductor Optical Amplifiers in VCSEL have that of for GaAs

Single point and asymmetric incremental forming

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Advances in Manufacturing 2015年第4期3卷 253-262页

作者： J. Jeswiet D. adams M. Doolan T. McAnulty P. Gupta Department of Mechanical and Materials Engineering Queen's University Kingston ON Canada Faculty of Engineering and Information Technology Australian National University Canberra Australia

This paper presents an update on single point incremental forming （SPIF） of sheet metal since 2005. It includes a description of the process with new information on the maximum forming angle, Фmax, for 5052-H32. An indepth example of the successful design and production of parts is given for industry. This includes discussion on production times and surface roughness with details that will help designers. A general design guide for users of SPIF is provided. It is based upon experience gained in the last decade. In general, materials show a trend of decreasing formability with increasing initial thickness. It is shown that for thicker sheet metal, it is recommended using large spherical tools （12.7 mm or larger）, or a large fiat-ended tool. The fiat-ended tool provides the best combination of good formability and very low surface roughness. For aluminum, galvanized steel and stainless steel, it is recommended using a fiat-ended tool. Advances in multi-pass techniques and information on successful and useful numerical models which predict forming behaviour are included. Finally, there is a discussion on future work needed in SPIF.

关键词： Single point incremental forming (SPIF) Design guide for SPIF Advances in SPIF

Security Analysis of a Privacy-Preserving Identity-Based Encryption Architecture

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Journal of Information Security 2022年第4期13卷 323-336页

作者： Carlisle adams School of Electrical Engineering and Computer Science University of Ottawa Ottawa Canada

Identity-Based Encryption (IBE) has seen limited adoption, largely due to the absolute trust that must be placed in the private key generator (PKG)—an authority that computes the private keys for all the users in the environment. Several constructions have been proposed to reduce the trust required in the PKG (and thus preserve the privacy of users), but these have generally relied on unrealistic assumptions regarding non-collusion between various entities in the system. Unfortunately, these constructions have not significantly improved IBE adoption rates in real-world environments. In this paper, we present a construction that reduces trust in the PKG without unrealistic non-collusion assumptions. We achieve this by incorporating a novel combination of digital credential technology and bilinear maps, and making use of multiple randomly-chosen entities to complete certain tasks. The main result and primary contribution of this paper are a thorough security analysis of this proposed construction, examining the various entity types, attacker models, and collusion opportunities in this environment. We show that this construction can prevent, or at least mitigate, all considered attacks. We conclude that our construction appears to be effective in preserving user privacy and we hope that this construction and its security analysis will encourage greater use of IBE in real-world environments.

关键词： Security Analysis Identity-Based Encryption (IBE) Reducing Trust Preserving Privacy Honest-but-Curious Attacker Malicious Attacker

Enduring legacy of coal mining on the fungal community in a High Arctic soil after five decades

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Pedosphere 2022年第5期32卷 698-706页

作者： Dorsaf KERFAHI Kevin K.NEWSHAM Ke DONG Hokyung SONG Mark TIBBETT Jonathan M.adams School of Natural Sciences Department of Biological SciencesKeimyung UniversityDaegu 42601(Republic of Korea) NERC British Antarctic Survey Madingley RoadCambridge CB3 OET(UK) Department of Life Science Kyonggi UniversitySuwon-si 16227(Republic of Korea) School of Earth and Environmental Sciences The University of ManchesterManchester M139PL(UK) Department of Sustainable Land Management&Soil Research Center School of AgriculturePolicy and DevelopmentUniversity of ReadingReading RG66AR(UK) School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210008(China)

Mineral extraction is known to affect soil fungi in polar environments,but it is unknown how long these effects ***,by amplifying the internal transcribed spacer regions of rRNA genes in soil fungi,we compared soil fungal community in intact natural tundra with that in a nearby former coal mining area,abandoned 52 years previously,on Svalbard in the High *** with those in intact tundra,soils in the former mining area were more acidic and had lower plant *** of similar diversity in the two areas,the fungal community was dominated by Basidiomycota in the intact tundra,but by Ascomycota in the former mining *** genera formed a major part of the tundra community,but were notably less abundant in the mining *** principal variation among samples was soil ***,network connectivity analysis indicated that the fungal community in the former mining area had greater network connectivity than that in the tundra ***,the ecosystem in the former mining area has made only limited recovery towards the natural tundra state even after more than five *** is unclear whether the recovery of the fungal community is limited more by the low primary productivity,slow migration of fungi and plants,or slow changes in soil *** findings emphasize the susceptibility of polar ecosystems to disturbance,given their particularly slow recovery back towards the natural state.

关键词： abandoned mining site ectomycorrhizal fungi intact tundra mine tailings mineral extraction polar ecosystem recovery

THE FINITE ELEMENT TECHNIQUE FOR PREDICTING THE NATURAL FREQUENCIES,MODE SHAPES AND DAMPING VALUES OF FILAMENTARY COMPOSITE PLATES

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Applied Mathematics and Mechanics(English Edition) 1986年第2期7卷 197-213页

作者：林敦祥倪荣根 R.D.adams Beijing Institute of Aeronautical Materials Shanxi Institute of Mechanical Engineering University of Bristol Xi’an U. K. Beijing

This article presents the numerical method for predicting the natural frequencies,mode shapes and damping values of filamentary composite *** method is based onfinite element technique,using damped element and allowing transverse shear *** the example of this technique,the theoretical results comparing with experimentalvalues of carbon and glass fibre reinforced plastics plates(mid-plane symmetric)*** dynamic properties of these laminates are ***,a simplegraphic technique to estimate the natural frequencies and damping values is suggested.

关键词： THE FINITE ELEMENT TECHNIQUE FOR PREDICTING THE NATURAL FREQUENCIES,MODE SHAPES AND DAMPING VALUES OF FILAMENTARY COMPOSITE PLATES SDC

Volume warrants for major and minor roads left-turning traffic lanes at unsignalized T-intersections： A case study using VISSIM modelling

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第5期5卷 417-428页

作者： Eric Nyame-Baafi Charles Anum adams Kwame Kwakwa Osei Urban Roads Department Ejisu Municipal Assembly Ejisu-Ashanti Region Ghana Department of Civil Engineerin9 Kwame Nkrumah University of Science and Technology Kumasi Ghana

The most common type of intersection improvement considered in Ghana is signalization. However, other actions such as the installation of left-turn lanes have been proven to improve the efficiency and safety of an intersection without the need for signalization in the short term. Warrants which guide the installation of such lanes in Ghana are adopted from elsewhere and as a result do not reflect local traffic flow conditions. This study established volume warrants based on a delay threshold to guide the installation of left- turn lanes at unsignalized T-intersections using VISSIM micro simulation tool. The VISSIM model was calibrated using traffic flow, delay, average and maximum queue length data obtained from a two-hour video recording of the case study intersection during the morning peak period. After calibration, several scenarios covering a wide range of opera- tional conditions were simulated. Using level of service （LOS） C cut off point of 25 s/veh as the maximum acceptable delay to minor road left-turning traffic, an equation y = -0.57x ＋1091 has been developed which predicts the minor road left-turn volume threshold （y） above which a minor road left-turn lane may be considered and below which a minor road left-turn lane may not be necessary for a range of major road volumes （x）. The critical delay to major road left-turning traffic was found to be 16 s/veh. Major road left-turn lane volume warrants were also determined based on this threshold delay value. The approach used in this study can serve as a guide that can be used by metropolitan and municipal road en- gineers to assess the need for left-turn lanes.

关键词： Unsignalized T-intersection Left-turn Warrants Delay Micro simulation VISSIM

Postoperative mortality and morbidity after D2 lymphadenectomy for gastric cancer:A retrospective cohort study

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World Journal of Gastroenterology 2022年第3期28卷 381-398页

作者： Giuseppe Brisinda Maria Michela Chiarello Anna Crocco Neill James adams Pietro Fransvea Serafino Vanella Abdominal Surgery Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy Department of Medical and Surgical Sciences UniversitàCattolica del Sacro CuoreRome 00168Italy General Surgery Operative Unit Azienda Sanitaria Provinciale di CrotoneOspedale San Giovanni di DioCrotone 88900Italy Endocrine Surgery Operative Unit Istituto Nazionale TumoriIRCCS Fondazione PascaleNapoli 80100Italy Health Sciences Clinical Microbiology UnitMagna Grecia UniversityCatanzaro 88100Italy Department of Emergency Surgery and Trauma Center Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy Department of General and Oncological Surgery Azienda Ospedaliera San Giuseppe MoscatiAvellino 83100Italy

BACKGROUND Surgery for gastric cancer is a complex procedure and lymphadenectomy is often *** mortality and morbidity after curative gastric cancer surgery is not *** To evaluate the factors determining mortality and morbidity in a population of patients undergoing R0 resection and D2 lymphadenectomy for gastric *** A retrospective analysis of clinical data and pathological characteristics(age,sex,primary site of the tumor,Lauren histotype,number of positive lymph nodes resected,number of negative lymph nodes resected,and depth of invasion as defined by the standard nomenclature)was conducted in patients with gastric *** each patient we calculated the Kattan’s *** arbitrarily divided the study population of patients into two groups based on the nomogram score(65 years),and number of lymph nodes retrieved(≤35 lymph nodes or>35 lymph nodes).Uni-and multivariate analysis of clinical and pathological findings were performed to identify the factors affecting postoperative mortality and *** One-hundred and eighty-six patients underwent a curative R0 resection with D2 *** mortality rate was 3.8%(7 patients);a higher mortality rate was observed in patients aged>65 years(P=0.002)and in N+patients(P=0.04).Following univariate analysis,mortality was related to a Kattan’s score≥100 points(P=0.04)and the presence of advanced gastric cancer(P=0.03).Morbidity rate was 21.0%(40 patients).Surgical complications were observed in 17 patients(9.1%).A higher incidence of morbidity was observed in patients where more than 35 lymph nodes were harvested(P=0.0005).CONCLUSION Mortality and morbidity rate are higher in N+and advanced gastric cancer *** removal of more than 35 lymph nodes does not lead to an increase in mortality.

关键词： Gastric cancer Total gastrectomy Subtotal gastrectomy Lymphadenectomy Kattan’s nomogram Mortality Postoperative complications Postoperative pancreatic fistula Hemoperitoneum Anastomotic leakage

AN ANALYSIS OF ANTONINUS PIUS’ FRONTIER POLICY IN NORTHERN BRITAIN AND ITS REPRESENTATION OF HIS PRINCIPATE

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Journal of Ancient Civilizations 2008年第1期23卷 119-137页

作者： Geoff adams

The accession of Antoninus Pius saw a distinct change in imperial frontier policy in Britain. Upon taking power, Antoninus’ representative in Britain, Q. Lollius Urbicus,1 undertook the systematic re-occupation of lo... 详细信息

关键词： AN ANALYSIS OF ANTONINUS PIUS FRONTIER POLICY IN NORTHERN BRITAIN AND ITS REPRESENTATION OF HIS PRINCIPATE