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Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David m.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi mihnea Surdu Dongyu Wang Lin Du imad el Haddad Jay G.Slowik Andre S.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

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A novel CmOS charge-pump circuit with current mode control 110mA at 2.7V for telecommunication systems

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Journal of Semiconductors 2010年第4期31卷 57-61页

作者： Salahddine Krit Hassan Qjidaa imad el Affar Yafrah Khadija Ziani messghati Yassir el-Ghzizal Faculty of Sciences Dhar el mehraz Laboratory of ElectronicSignal-Systymes and Informatic(LESSI)FesMorocco

This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSmC 0.35-μm CmOS technology and operates with a 2.7 to 3.6 V supply voltage. It has an area of 0.4 mm^2; it was designed with a frequency regulation of 1 mHz and internal current mode to reduce power consumption.

关键词： switch capacitor charge pump voltage doubler power consumption

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Epidemiology of type 2 diabetes in the middle East and North Africa:Challenges and call for action

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World Journal of Diabetes 2021年第9期12卷 1401-1425页

作者： imad m el-Kebbi Nayda H Bidikian Layal Hneiny mona Philippe Nasrallah Department of Internal medicine Division of EndocrinologyAmerican University of Beirut Medical CenterFaculty of MedicineBeirut 11072020Lebanon Department of Internal medicine Sheikh Shakhbout Medical CityAbou Dhabi 11001United Arab Emirates School of medicine American University of BeirutFaculty of MedicineBeirut 11072020Lebanon University Libraries Saab Medical LibraryAmerican University of BeirutBeirut 11072020Lebanon

Type 2 diabetes continues to be a serious and highly prevalent public health problem *** 2019,the highest prevalence of diabetes in the world at 12.2%,with its associated morbidity and mortality,was found in the middle East and North Africa *** addition to a genetic predisposition in its population,evidence suggests that obesity,physical inactivity,urbanization,and poor nutritional habits have contributed to the high prevalence of diabetes and prediabetes in the *** risk factors have also led to an earlier onset of type 2 diabetes among children and adolescents,negatively affecting the productive years of the youth and their quality of ***,efforts to control the rising prevalence of diabetes and its complications have been challenged and complicated by the political instability and armed conflict in some countries of the region and the recent coronavirus disease *** strategies,coupled with targeted interventions at the regional,national,and community levels are needed to address and curb the spread of this public health crisis.

关键词： Type 2 diabetes middle East and North Africa Epidemiology Prevalence Prediabetes Complications

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Role of urine studies in asymptomatic febrile neutropenic patients presenting to the emergency department

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World Journal of Emergency medicine 2021年第2期12卷 99-104页

作者： Hady Zgheib Aline el zakh.m Cynthia Wakil mohamad Ali Cheaito Rola Cheaito Antoine Finianos Ralphe Bou Chebl Rima Kaddoura Nader Al Souky imad el majzoub Department of Emergency medicine American University of Beirut Medical CenterBeirut 11-0236Lebanon Department of Internal medicine American University of Beirut Medical CenterBeirut 11-0236Lebanon

BACKGROUND: The role of urine studies in the detection of urinary tract infection(UTI) in febrile neutropenic patients with urinary symptoms(having a urinary catheter or having a positive urine analysis) is inarguable. However, the evidence is scarce regarding the indication for urine studies in asymptomatic(i.e., without urinary symptoms) patients with febrile neutropenia(FN) presenting to the emergency department(ED). The aim of this study is to evaluate the need for obtaining urine studies in asymptomatic febrile neutropenic ***: This was a retrospective cohort study conducted on adult cancer patients who presented to the ED with FN and had no urinary symptoms. We included all ED presentations of eligible patients between January 2013 and September 2018. Student's t-test and Wilcoxon rank-sum test were used for continuous data, while Chi-square and Fisher's exact tests were used for categorical data. Participants were divided into two groups based on their urine culture(UC) results: negative and positive UCs. Two cut-offs were used for positive UC results: ≥10~5 cfu/m L and ≥10~4 cfu/m ***: We included 284 patients in our study. The age of our patient population was 48.5±18.5 years. more than two-thirds(68.7%) of patients had severe neutropenia, while only 3.9% and 9.9% of the patients had positive UCs at ≥10~5 cfu/m L and ≥10~4 cfu/m L, respectively. UCs were expectedly positive in most patients with urinalysis(UA) abnormalities. However, 27.3% and 32.1% of patients with positive UCs at ≥10~5 cfu/m L and ≥10~4 cfu/m L respectively had a normal UA. CONCLUSIONS: In our study, the incidence of UTI in adult febrile neutropenic cancer patients who present to the ED without urinary symptoms is low. Consequently, routine urine testing may not be warranted in this population, as it adds unnecessary financial burdens on the patients and delays timely management.

关键词： Adult Cancer Emergency department Febrile neutropenia Urine testing

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Dynamic evaluation of jack-up platform structure under wave, wind, earthquake and tsunami loads

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Journal of Ocean Engineering and Science 2022年第1期7卷 41-57页

作者： Zaid mohammed Ghazi imad Shakir Abbood Farzad Hejazi Department of Civil Engineering Universiti Putra MalaysiaMalaysia Engineering Affairs Department Sunni Endowment DiwanBaghdadIraq

Nowadays,the demand for using jack-up platforms to carry out a large percentage of deep-water oil and gas exploration is steadily *** response of jack-up platforms to the severe dynamic loads that may be encountered during the structure life is not examined ***,this study attempts to investigate the response of jack-up platforms performance under the effect of dynamic loads due to wave,wind,earthquake and tsunami forces using the finite element method for two models with the lowest and highest hull *** jack-up platform is located in the Gulf of *** ac-celerations are applied to the model in high and moderate seismic *** addition,tsunami waves are applied to the platform in three different directions at 0°,45°and 90°.This study utilised Airy’s linear wave approach to assess the surface elevations and wave *** reference wind velocity is 10 knots at 10 m over the mean water *** indicate that the dynamic response of the structure is affected by the height of the platform and by the increase of the platform hull *** combination of the el-Centro earthquake,dead and live loads provides the major impact on the platform at the lowest(70 m)and highest(85 m)hull *** comparison of all result proves that the jack-up platform hull under high earthquake intensity and tsunami waves with 45°has experienced maximum ***,raising the deck will increase the response of the dynamic load and displacements but will negatively affect the platform.

关键词： Offshore structures Earthquake Dynamic excitation Jack-up platform Tsunami Seismic zone

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Distribution and variability of deformed wing virus of honeybees （Apis mellifera） in the middle East and North Africa

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Insect Science 2017年第1期24卷 103-113页

作者： Nizar Jamal Haddad Adjlane Noureddine Banan Al-Shagour Wahida Loucif-Ayad mogbel A. A. el-Niweiri Eman Anaswah Wafaa Abu Hammour Dany el-Obeid Albaba imad mohamed A. Shebl Abdulhusien Sehen Almaleky Abdullah Nasher Nagara Walid mohamed Fouad Bergigui Orlando Yanez Joachim R. de miranda Bee Research Department National Center for Agriculture Research and Extension Baq'a Jordan Department of Biology M'hamed Bougare University of Boumerdes ENS Kouba Algeries Laboratory of Applied Animal Biology University Badji-Mokhtar Annaba Algeria Department of Bee Research Environment Natural Resources and Desertification Research Institute National Centre for Research Khartoum Sudan Faculty of Agriculture and Veterinary Sciences Lebanese University Beirut Lebanon West Bank State of Palestine HalhuI-Hebron District Palestine Department of Plant Protection Suez Canal University Ismailia Egypt Extension Department Qadysia Govemate Agricultural Directorate Iraq Department of Plant Protection Sana'a University Sane'a Yemen National Federation of Tunisian beekeepers Tunis Tunisia Ruchers el Bakri Hay Assalam-Sidi Slimane Rabat Morocco Institute of Bee Health Vetsuisse Faculty University of Bern Bern Switzerland Department of Ecology Swedish University of Agricultural Sciences Uppsala Sweden

Three hundred and eleven honeybee samples from 12 countries in the middle East and North Africa （mENA）（Jordan, Lebanon, Syria, Iraq, Egypt, Libya, Tunisia, Algeria, morocco, Yemen, Palestine, and Sudan） were analyzed for the presence of deformed wing virus （DWV）. The prevalence of DWV throughout the mENA region was pervasive, but variable. The highest prevalence was found in Lebanon and Syria, with prevalence dropping in Palestine, Jordan, and Egypt before increasing slightly moving westwards to Algeria and morocco Phylogenetic analysis of a 194 nucleotide section of the DWV Lp gene did not identify any significant phylogenetic resolution among the samples, although the sequences did show consistent regional clustering, including an interesting geographic gradient from morocco through North Africa to Jordan and Syria. The sequences revealed several clear variability hotspots in the deduced amino acid sequence, which furthermore showed some patterns of regional identity. Furthermore, the sequence variants from the middle East and North Africa appear more numerous and diverse than those from Europe.

关键词： Apis mellifera deformed wing virus middle East North Africa prevalence variability

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