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Assessment of the carbon abatement and removal opportunities of the Arabian Gulf Countries

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Clean Energy 2021年第2期5卷 340-353页

作者： Abdulrahman Alatiq Wail Aljedani Abdullah Abussaud Omar Algarni Hélène Pilorgé Jennifer Wilcox Department of Chemical Engineering Worcester Polytechnic InstituteGoddard Hall100 Institute RoadWorcesterMA 01609USA Department of Chemical and Biomolecular Engineering University of Pennsylvania220 S.33rd StreetPhiladelphiaPA 19104USA

The Arabian Gulf Countries(AGC)are strongly reliant on the economic export of fossil fuels,while being vulnerable to climate change that is resulting in temperature increase,air pollution and sea-level rise,and threatening the health of the population and *** agreement with the paris Accords,most of the AGC have published short-term goals to reduce their carbon emissions in the coming *** relation to these goals,this study explores the potential CO_(2)reduction,avoidance and removal in the region,by comparing a business-as-usual(BAU)scenario to three decarbonization scenarios for the power *** 2018,the total greenhouse gas(GHG)emissions in the AGC were~1333 MtCO_(2)/yr and are expected to rise to 1568 MtCO_(2)/yr in 2030 following a BAU scenario,which is likely to be reduced to 1522 MtCO_(2)/yr in 2030 by following the countries’*** issued plans for the coming decades that focus on increasing the share of renewable energy in their grid *** three decarbonization scenarios presented in this study focus on supply-side technological *** retirement of the oldest natural-gas and oil power plants could lead to a total emissions reduction of~75 MtCO_(2)/yr,without accounting for the embodied carbon emissions associated with renewable *** addition,the implementation of point-source capture at power plants expected to retire in>10 years’time could avoid emissions of~240 MtCO_(2)/yr,provided the CO_(2)is permanently sequestered in appropriate geological *** region also shows high-quality solar resources and large CO_(2)-storage potential that could couple to direct air-capture plants to offset difficult-to-avoid *** last scenario has the potential to ultimately result in net negative emissions.

关键词： carbon capture CCUS direct air capture

Effects of Exhaust Gas Recirculation on the Homogeneous Charge Combustion Process of n-Heptane at Different load Conditions

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Transactions of Tianjin University 2005年第4期11卷 262-267页

作者：刘德新冯洪庆郑进才 MIllER David l CERNANSKY Nicholas P State Key laboratory of Engines School of Mechanical Engineering Tianjin University Tianjin 300072 China Department of Mechanical Engineering Drexel University Philadelphia PA19104-2875 USA

Effects of exhaust gas recirculation （EGR） on homogeneous charge combustion of n-heptane was studied through simulation and experiment. Experiments were carried out in a single cylinder, four-stroke, air cooled engine and a single cylinder, two-stroke, water cooled engine. In the four-stroke engine, experiments of the effects of EGR were examined using heated N2 addition as a surrogate for external EGR and modifying engine to increase internal EGR. The ignition timing was sensitive to EGR due to thermal and chemical effects. EGR or extra air is a key factor in eliminating knock during mid-load conditions. For higher load operation the only way to avoid knock is to control reaction timing through the use of spark ignition. Experimental and modeling results from the two-stroke engine show that auto-ignition can be avoided by increasing the engine speed. The two-stroke engine experiments indicate that high levels of internal EGR can enable spark ignition at lean conditions. At higher load conditions, increasing the engine speed is an effective method to control transition from homogeneous charge compression ignition （HCCI） operation to non-HCCI operation and successful spark ignition of a highly dilute mixture can avoid serious knock.

关键词： homogeneous charge combustion exhaust gas recirculation n-heptane auto-ignition

pancreatic head excavation for tissue diagnosis may reduce unnecessary pancreaticoduode- nectomies in the setting of chronic pancreatitis

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Hepatobiliary & pancreatic Diseases International 2017年第3期16卷 315-322页

作者： Alessandro Fancellu Giorgio C Ginesu Claudio F Feo Maria l Cossu Marco Puledda Antonio Pinna Alberto Porcu Department of Clinical and Experimental Medicine Unit of General Surgery 2 - Clinica Chirurgica University of Sassari V.le San Pietro 43 07100 Sassari Italy

BACKGROUND： The necessity to obtain a tissue diagnosis of cancer prior to pancreatic surgery still remains an open debate. In fact, a non-negligible percentage of patients under- going pancreaticoduodenectomy （PD） for suspected cancer has a benign lesion at final histology. We describe an approach for patients with diagnostic uncertainty between cancer and chronic pancreatitis, with the aim of minimizing the incidence of PD for suspicious malignancy finally diagnosed as benign disease. METHODS： Eighty-eight patients （85.4%） with a clinicoradio- logical picture highly suggestive for malignancy received for- mal PD （group 1）. Fifteen patients （14.6%） in whom preopera- tive diagnosis was uncertain between pancreatic cancer and chronic pancreatitis underwent pancreatic head excavation （PHEX） for intraoperative tissue diagnosis （group 2）： those diagnosed as having cancer received PD, whereas those with chronic pancreatitis received pancreaticojejunostomy （P]）. RESUlTS： No patient received PD for benign disease. All pa- tients in group I had adenocarcinoma on final histology. Eight patients of group 2 （53.3%） received PD after intraoperative diagnosis of cancer, whereas 7 （46.7%） received PJ because no malignancy was found at introperative frozen sections. No signs of cancer were encountered in patients receiving PHEX and PJ after a median follow-up of 42 months. Overall survival did not differ between patients receiving PD for cancer in the group 1 and those receiving PD for cancer after PHEX in the group 2 （P=0.509）. CONClUSION： Although the described technique has been used in a very selected group of patients, our results suggest that PHEX for tissue diagnosis may reduce rates of unnecessary PD, when the preoperative diagnosis is uncertain between cancer and chronic pancreatitis.

关键词： pancreatic carcinoma chronic pancreatitis pancreaticoduodenectomy pancreatic head excavation

Sonicating bees demonstrate flexible pollen extraction without instrumental learning

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Current Zoology 2019年第4期65卷 425-436页

作者： Callin M. Switzer Avery l. Russell Daniel R. papaj Stacey A. Combes Robin Hopkins Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA Arnold Arboretum Harvard University Boston MA USA Department of Ecology and Evolutionary Biology University of Arizona Tucson AZ USA Department of Neurobiology Physiology and Behavior University of California at Davis Davis CA USA Department of Biology and eScience Institute University of Washington Seattle WA USA Department of Biological Sciences University of Pittsburgh Pittsburgh PA USA

Pollen collection is necessary for bee survival and important for flowering plant reproduction, yet if and how pollen extraction motor routines are modified with experience is largely unknown. Here, we used an automated reward and monitoring system to evaluate modification in a common pollen-extraction routine, floral sonication. Through a series of laboratory experiments with the bumblebee, Bombus impatiens, we examined whether variation in sonication frequency and acceleration is due to instrumental learning based on rewards, a fixed behavioral response to rewards, and/or a mechanical constraint. We first investigated whether bees could learn to adjust their sonication frequency in response to pollen rewards given only for specified frequency ranges and found no evidenee of instrumental learning. However, we found that absenee versus receipt of a pollen reward did lead to a predictable behavioral resp on se, which depe nded on bee size. Fin ally, we found some evide nee of mechanical con straints, in that flower mass affected sonication acceleration (but not frequency) through an interaction with bee size. In generalz larger bees showed more flexibility in sonication frequency and acceleration, potentially reflecting a size-based constraint on the range over which smaller bees can modify frequency and accelerati on. Overall our results show that although bees did not display instrumental learning of sonication frequency, their sonication motor routine is nevertheless flexible.

关键词： Bombus impatiens buzz pollination foraging innate behavior learned behavior Solanum

EFFECT OF Ar PRESSURE ON STRUCTURAl AND ElECTRICAl PROPERTIES OF Cu FIlMS DEPOSITED ON GlASS BY DC MAGNETRON SPUTTERING

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Acta Metallurgica Sinica(English letters) 2002年第1期15卷 39-44页

作者： P. Wu F.P. Wang l.Q. pan Y. Tian H. Qiu Department of Physics University of Science and Technology Beijing Beijing 100083China Beijing Keda-Tianyu Microelectronic Material Technology Development Co. ltd. Beijing 100083 China

Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5pa respectively. The target voltage was fixed at 500V but the target current increased from 200 to 1150mA with Ar pressure increasing. X-ray diffraction, scanning electron microscopy and atomic force microscopy were used to observe the structural characterization of the films. The resistivity of the films was measured using four-point probe technique. At all the Ar pressures, the Cu films have mixture crystalline orientations of [111], [200] and [220] in the direction of the film growth. The film deposited at lower pressure shows more [111] orientation while that deposited at higher pressure has more [220] orientation. The amount of larger grains in the film prepared at 0.5pa Ar pressure is slightly less than that prepared at 1.0pa and 1.5pa Ar pressures. The resistivities of the films prepared at three different Ar pressures represent few differences, about 3-4 times of that of bulk material. Besides the deposition rate increases with Ar pressure because of the increase in target current. The contribution of the bombardment of energetic reflected Argon atoms to these phenomena is discussed.

关键词： Cu film DC magnetron sputtering deposition Ar pressure structure reststivity

Pharmacological applications of a novel neoepitope antibody to a modified amyloid precursor protein-derived beta-secretase product

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Protein & Cell 2011年第7期2卷 573-584页

作者： Guoxin Wu Sethu Sankaranarayanan Donna l.Montgomery Adam J.Simon Zhiqiang An Mary J.Savage Department of Neurology Merck Research LaboratoryWest PointPA 19486USA Department of Biologics Research Merck Research LaboratoryWest PointPA 19486USA

We have previously described a novel artificial NFEVβ-secretase(BACE1)cleavage site,which when introduced into the amyloid-βprecursor protein(APP),significantly enhances APP cleavage by BACE1 in in vitro and cellular *** this study,we describe the identification and characterization of a single chain fragment of variable region(scFv),specific to the EV neo-epitope derived from BACE1 cleavage of the NFEV-containing peptide,and its conversion to *** the scFv displayed on phage and EV-IgG1 show exquisite specificity for binding to the EV neoepitope without cross-reactivity to other NFEV containing peptides or WT-APP KMDA cleavage ***-IgG1 can detect as little as 0.3 nmol/l of the EV ***-IgG1 antibody was purified,conjugated with alkaline phosphatase and utilized in various biological *** the BACE1 enzymatic assay using NFEV substrate,a BACE1 inhibitor MRK-3 inhibited cleavage with an IC50 of 2.4 nmol/l with excellent *** an APP_NFEV stable SH-SY5Y cellular assay,the EC_(50) for inhibition of EV-Aβ peptide secretion with MRK-3 was 236 nmol/l,consistent with values derived using an EV polyclonal *** an APP_NFEV knock-in mouse model,both Aβ_EV40 and Aβ_EV42 peptides in brain homogenate showed excellent gene dosage *** conclusion,the EV neoepitope specific monoclonal antibody is a novel reagent for BACE1 inhibitor discovery for both in vitro,cellular screening assays and in vivo biochemical *** methods described herein are generally applicable to novel synthetic substrates and enzyme targets to enable robust screening platforms for enzyme inhibitors.

关键词： scFv antibody BACE1 amyloid-βprecursor protein(APP) immunoassay

国民教育经济意义的数量化——试算我国教育的经济效益

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西南师范学院学报(自然科学版) 1984年第3期 64-71页

作者：蒲心文西南师范学院教育系

国民教育经济意义的数量化,既从历史的角度对教育的经济价值进行了定性的论证,更从国内、外采用复杂劳动简化法,和教育投资收益率概算法,把教育具有的经济价值进行了定量的论证.概算出:(1)我国1952年—1978年教育对国民收入增长的贡献为... 详细信息

国民教育经济意义的数量化,既从历史的角度对教育的经济价值进行了定性的论证,更从国内、外采用复杂劳动简化法,和教育投资收益率概算法,把教育具有的经济价值进行了定量的论证.概算出:(1)我国1952年—1978年教育对国民收入增长的贡献为8.3％;(2)四川省绵竹县1982年农民身上积累的教育潜力,对当年农业总产值的贡献为15％;(3)重庆第二钢铁厂1981年的职工教育投资,到1983年的纯收益为投资的2.79倍.这些定性、定量的论证,对于国家计划经济、编制财政预算,合理分配教育投资和固定资产的投资有一定参考意义.

关键词：投资收益率国民经济综合经济经济效益劳动简化法国民经济净产值经济收入国民收入工作量劳动量数量化试算

Prevalence of hepatocarcinoma-related hepatitis B virus mutants in patients in grey zone of treatment

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World Journal of Gastroenterology 2019年第38期25卷 5883-5896页

作者： Ana Isabel Gil-García Antonio Madejón Irene Francisco-Recuero Ana lópez-lópez Emiliana Villafranca Miriam Romero Araceli García Antonio Olveira Rocío Mena Juan Ramón larrubia Javier García-Samaniego Hepatology Unit Hospital Universitario La PazMadrid 28046Spain Centro de Investigación Biomédica en Red Instituto de Salud Carlos IIIMadrid 28029Spain Instituto de Investigación del Hospital Universitario la paz Madrid 28046Spain Biochemistry Department Faculty of MedicineUniversidad Autónoma de MadridMadrid 28029Spain Instituto de Genética Médica y Molecular Hospital Universitario La PazMadrid 28046Spain Translational Hepatology Unit Hospital General Universitario de GuadalajaraGuadalajara 19002Castilla-La ManchaSpain

BACKGROUND Antiviral treatment of patients with chronic hepatitis B(CHB)in the grey zone of treatment comands risk management in order to optimize the health *** this sense,the identification of HBV mutants related with an increased risk of hepatocellular carcinoma(HCC)could be useful to identify subpopulations with potential indication of antiviral *** To analyze the prevalence/persistence of hepatitis B virus(HBV)preS and basal core promoter(BCP)/precore/core variants associated to HCC development in CHB patients in the grey *** Work was designed as a longitudinal retrospective study,including 106 plasma samples from 31 patients with CHB in the grey zone of treatment:Hepatitis B e antigen negative,HBV-DNA levels between 12-20000 IU/ml,normal or discordant transaminase levels during follow up and mild/moderate necroinflammatory activity in liver biopsy or Fibroscan(up to 9.5 kpa).Serum HBVDNA was tested using the Abbott Real Time HBV Assay and the BCP/precore/core and the hepatitis B surface antigen(HBsAg)coding regions were analyzed in positive samples by PCR/bulk-sequencing to identify the HCCrelated HBV *** High-risk HCC related mutants were detected in 24(77%)patients:19(61%)in the BCP/precore/core,and 7(23%)in the HBsAg coding region(2 preS1 and 5 preS2 deletions).The prevalence of preS deletions was genotype-dependent:3/5(60%)patients with preS2 deletions and 1/2 with preS1 deletions were infected with the HBV-E *** HBV-E was the most prevalent in sub-Saharan patients,a correlation between preS deletions and ethnicity was also found:6/8(75%)sub-Saharan vs 1/19(5%)Caucasian patients had preS deletions(P=0.00016).Remarkably,this correlation was maintained in those patients infected with HBV-A,a minor genotype in sub-Saharan patients:2/2 patients infected with HBV-A from West Africa vs 0/6 of Caucasian origin had preS *** HCC related variants were the major strains and persisted over time(up to 48 mo).pa

关键词： Hepatitis B virus Hepatocellular carcinoma PreS deletions Hepatitis B virus treatment Grey zone

Treatment of inflammatory bowel disease:A review of medical therapy

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World Journal of Gastroenterology 2008年第3期14卷 354-377页

作者： patricia l Kozuch Stephen B Hanauer Division of Gastroenterology and Hepatology Department of Medicine Thomas Jefferson University Hospital Philadelphia PA United States University of Chicago Hospitals Department of Medicine Section of Gastroenterology and Nutrition Chicago IL 60637 United States

Crohn’s disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal tract. While a cure remains elusive, both can be treated with medications that induce and maintain remission. With the recent advent of therapies that inhibit tumor necrosis factor (TNF) alpha the overlap in medical therapies for UC and CD has become greater. Although 5-ASA agents have been a mainstay in the treatment of both CD and UC, the data for their efficacy in patients with CD, particularly as maintenance therapy, are equivocal. Antibiotics may have a limited role in the treatment of colonic CD. Steroids continue to be the first choice to treat active disease not responsive to other more conservative therapy; non- systemic steroids such as oral and rectal budesonide for ileal and right-sided CD and distal UC respectively are also effective in mild-moderate disease. 6-mercaptopurine (6-MP) and its prodrug azathioprine are steroid-sparing immunomodulators effective in the maintenance of remission of both CD and UC, while methotrexate may be used in both induction and maintenance of CD. Infliximab and adalimumab are anti-TNF agents approved in the US and Europe for the treatment of Crohn's disease, and infliximab is also approved for the treatment of UC.

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Medical therapy