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Quantum Interferometry for Different Energy Landscapes in a Tuneable Josephson Junction Circuit

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Journal of Applied Mathematics and Physics 2020年第11期8卷 2569-2600页

作者： Pernel Nguenang michael nana jipdi Patrick Louodop Martin Tchoffo Lukong Cornelius Fai Hilda A. Cerdeira Research Unit Condensed Matter Electronics and Signal Processing Université de Dschang Dschang Cameroon Department of Physics Higher Teacher Training College University of Bamenda Bambili Cameroon Sã o Paulo State University (UNESP) Instituto de Física Teórica Barra Funda S&#227 o Paulo Brazil Centre d’études et de Recherches en Agronomie et en Biodiversité Faculté d’Agronomie et des Sciences Agricoles University of Dschang Dschang Cameroon

This paper presents a simple Josephson-junction circuit with two parameters (inductance and capacitance) which can be tuned to represent different energy landscapes with different physical properties. By tuning this quantum circuit through external accessible elements we can move from two to three and more energy levels depending on the parameter setting. The inductance, the capacitance as well as the external voltage (driving terms) condition the number of relevant energy levels as well as the model to be used. We show that the quantized circuit represents a multi-state system with tunneling induced by the Landau-Zener and Landau-Zener-Stückelberg transition. The special cases of single crossing and multi-crossing models are thoroughly studied and the transition probability is obtained in each case. It is proven that, the crossing time as well as the relaxation time affect drastically the transition probability;the system mimics a single passage for short relaxation and a multiple passage problem for large relaxation. The nonlinearity of energy levels modifies the transition probability and the derived adiabatic parameters help to redefine the Landau-Zener probability. The observed constructive and destructive interferences are parametrically conditioned by the initial condition set by the inductive branch. Moreover, the total population transfers as well as the complete blockage of the system are obtained in a permissible range of parameters only by changing the values of the inductance. Therefore, the system models a controllable level-crossing where the additional branches (inductive and capacitive) help in designing the number of states, the type of interferometry as well as the control of states occupation.

关键词： Josephson Junction Tuneable Josephson Junction Energy Landscapes Quantum Interferometry

Interactive effects of water stress and powdery mildew(Blumeria graminis)on the alkaloid production of Achnatherum inebrians infected by Epichlo?endophyte

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Science China(Life Sciences) 2018年第7期61卷 864-866页

作者： nana Li Chao Xia Rui Zhong Yawen Ju Zhibiao Nan michael J Christensen Xingxu Zhang State Key Laboratory of Grassland Agro-ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of AgricultureCollege of Pastoral Agricultural Science and TechnologyLanzhou UniversityLanzhou 730020China AgResearch Grasslands'Research CentrePrivate Bag 11-008Palmerston North 4442New Zealand

Dear Editor,Achnatherum inebrians,also known as drunken horse grass（DHG）,is a toxic perennial bunch grass that can be infected by Epichloegansuensis or ***（Chen et al.,2015）.It is well known that Epichloefungal endophytes can protect their host plants from herbivores by producing different classes of alkaloids.A recent trial demonstrated that sheep exhibited notable toxicity symptoms by directly feeding with endophyte-infected（E＋）***（Liang et al.,2017）.

关键词：寄生植物感染生产应力和交互草食动物水碱

Disinfection byproducts and halogen-specific total organic halogen speciation in chlorinated source waters——The impact of iopamidol and bromide

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Journal of Environmental Sciences 2020年第3期32卷 90-101页

作者： nana Osei B.Ackerson Hannah K.Liberatore michael J.Plewa Susan D.Richardson Thomas A.Ternes Stephen E.Duirk Department of Civil Engineering University of AkronAkronOH 44325USA Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC 29208USA Department of Crop Sciences and Safe Global Water Institute University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Federal Institute of Hydrology(BfG) D-56068 KoblenzGermany

This study investigated the speciation of halogen-specific total organic halogen and disinfection byproducts(DBPs) upon chlorination of natural organic matter(NOM) in the presence of iopamidol and bromide(Br^-).Experiments were conducted with low bromide source waters with different NOM characteristics from Northeast Ohio,USA and varied spiked levels of bromide(2-30 μmol/L) and iopamidol(1-5 μmol/L).Iopamidol was found to be a direct precursor to trihalomethane(THM) and haloacetic acid formation,and in the presence of Br^-favored brominated *** concentration and speciation of DBPs formed were impacted by iopamidol and bromide concentrations,as well as the presence of *** iopamidol increased the concentration of iodinated DBPs(iodo-DBPs) and THMs ***,as Br^-concentrations increased,the concentrations of nonbrominated iodo-and chloro-DBPs decreased while brominated-DBPs *** of the concentration of either iopamidol or bromide,bromochloroiodomethane(CHBrClI) was the most predominant iodo-DBP formed except at the lowest bromide concentration *** relevant concentrations of iopamidol(1 μmol/L) and bromide(2 μmol/L),significant quantities of highly toxic iodinated and brominated DBPs were ***,the rapid oxidation and incorporation of bromide appear to inhibit iodoDBP formation under conditions relevant to drinking water treatment.

关键词： Iopamidol Total organic halogen(TOX) Disinfection byproducts(DBPs) Chlorine Natural organic matter(NOM) pH

Impact of chlorine exposure time on disinfection byproduct formation in the presence of iopamidol and natural organic matter during chloramination

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Journal of Environmental Sciences 2019年第4期31卷 204-214页

作者： nana Osei B.Ackerson Alexis H.Killinger Hannah K.Liberatore Thomas A.Ternes michael J.Plewa Susan D.Richardson Stephen E.Duirk Department of Civil Engineering University of Akron Department of Chemistry and Biochemistry University of South Carolina Federal Institute of Hydrology (BfG) Department of Crop Sciences and Safe Global Water Institute and NSF Science and Technology Center of Advanced Materials for the Purification of Water with Systems University of Illinois at Urbana-Champaign

Chloramines,in practice,are formed onsite by adding ammonia to chlorinated drinking water to achieve the required *** regulated disinfection byproducts(DBPs)are reduced during chloramine disinfection,other DBPs such as iodinated(iodo-)DBPs,that elicit greater toxicity are *** objective of this study was to investigate the impact of prechlorination time on the formation of both halogen-specific total organic halogen(TOX)and iodo/chlorinated(chloro-)DBPs during prechlorination/chloramination in source waters(SWs)containing iopamidol,an X-ray contrast *** SW(BSW)and Cleveland SW(CSW)containing iopamidol were prechlorinated for 5–60 min and afterwards chloraminated for 72 hr with ammonium *** contact time(CCT)did not significantly impact total organic iodine(TOI)concentrations after prechlorination or *** of total organic chlorine(TOCl)formed during prechlorination did not significantly change regardless of pH and prechlorination time,whileTOClappearedtodecreaseafter 72 ***(CHCl_2I)formation during prechlorination did not exhibit any significant trends as a function of p H or CCT,but after chloramination,significant increases were observed at pHs 6.5 and 7.5 with respect to ***-HAAs were not formed during prechlorination but were detected after *** quantities of chloroform(CHCl_3)and trichloroacetic acid(TCAA)were formed during prechlorination but formation ceased upon ammonia ***,prechlorination studies should measure TOX and DBP concentrations prior to ammonia addition to obtain data regarding the initial conditions.

关键词： Prechlorinaton Iopamidol Monochloramine Disinfection byproducts(DBPs) Total organic chlorine(TOCl) Total organic iodine(TOI)

Anion cascade reactions Ⅲ:Synthesis of 3-isoquinuclidone bridged polycyclic lactams

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Chinese Chemical Letters 2024年第2期35卷 426-430页

作者： Zhiguo Zhang Bingbing Shi Xiyang Cao nana Ma Hao Wu Xingjie Zhang Guisheng Zhang Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Centre of Henan Province for Green Manufacturing of Fine ChemicalsNMPA Key Laboratory for Research and Evaluation of Innovative DrugSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China

Bridged polycyclic lactams are important structural units in organic functional materials,natural products,and pharmaceuticals.A flexible and efficient anion cascade reaction was developed for the preparation of bridged polycyclic lactams from readily available malonamides and 1,4‑*** highly substituted bridged polycyclic lactams were synthesized in good to excellent yields by tandem nucleophilic sequences in the presence of t BuOK in commercially available EtOH solvent at 60℃.Notably,the simple reactions can be run on a gram ***,bis-michael addition reaction and hemiaminalization reactions are involved in the tandem transformation.

关键词： Anion cascade reactions 3-Isoquinuclidone Bridged polycyclic lactams Bis-michael addition reaction Hemiaminalization

Analysis of Public Sentiment regarding COVID-19 Vaccines on the Social Media Platform Reddit

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Journal of Computer and Communications 2024年第2期12卷 80-108页

作者： Lucien Dikla Ngueleo Jules Pagna Disso Armel Ayimdji Tekemetieu Justin Moskolaï Ngossaha michael nana Kameni African Institute for Mathematical Sciences (AIMS)/AIMS-Cameroon Limbe Cameroon Department of Mathematics and Computer Science Faculty of Science University of Douala Douala Cameroon WMG (Warwick Manufacturing Group) University of Warwick Coventry UK School of Information Studies McGill University Montreal Canada

This study undertakes a thorough analysis of the sentiment within the r/Corona-virus subreddit community regarding COVID-19 vaccines on Reddit. We meticulously collected and processed 34,768 comments, spanning from November 20, 2020, to January 17, 2021, using sentiment calculation methods such as TextBlob and Twitter-RoBERTa-Base-sentiment to categorize comments into positive, negative, or neutral sentiments. The methodology involved the use of Count Vectorizer as a vectorization technique and the implementation of advanced ensemble algorithms like XGBoost and Random Forest, achieving an accuracy of approximately 80%. Furthermore, through the Dirichlet latent allocation, we identified 23 distinct reasons for vaccine distrust among negative comments. These findings are crucial for understanding the community’s attitudes towards vaccination and can guide targeted public health messaging. Our study not only provides insights into public opinion during a critical health crisis, but also demonstrates the effectiveness of combining natural language processing tools and ensemble algorithms in sentiment analysis.

关键词： COVID-19 Vaccine TextBlob Twitter-RoBERTa-Base-Sentiment Sentiment Analysis Latent Dirichlet Allocation

Traditional Use of Medicinal Plants Confirmed by the Baka in Southern and Eastern Cameroon

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Journal of Biosciences and Medicines 2024年第8期12卷 76-106页

作者： Natacha nana Afiong Pascal Billong Fils Karelle Kouetchua Guekam Eloge Kambale Muhesi Eva Avila Martin Guillermo Ros Brull Julia E. Fa Stephan michael Funk Evariste Fongnzossie Fedoung Jean Lagarde Betti Department of Biology and Physiology of Plant Organisms University of Douala Douala Cameroon Zerca y lejos ONGD Madrid Spain Department of Natural Sciences School of Science and the Environment Manchester Metropolitan University Manchester UK Center for International Forestry Research (CIFOR) CIFOR Headquarters Bogor Indonesia Nature Heritage Jersey Channel Islands Manchester UK Laboratory of Forest Resources and Wood Valorization Training Unit in Engineering Sciences Post Graduate School of Fundamental and Applied Sciences University of Douala Douala Cameroun Department of Wood Sciences Higher Institute of Agriculture Wood Water resources and Environment University of Ber-toua Bertoua Cameroon

The limitations of biomedecine to provide effective solutions to certain pandemics has led many people to turn to alternative therapies. These palliative solutions, particularly phytomedecines, are much sought after for disease prevention and treatment. The Baka, a group of forest-dwelling people, hold knowledge on how wild plants can be effective in treating many illnesses. However, the greatest challenge for the identification of traditional medicines depends on the veracity of the information provided during ethnobotanic surveys by user populations. The present study describes forest plants used by the Baka and confirmed by them as being employed for traditional medicine. We carried out ethnobotanical surveys between 2019 and 2021 in 221 households within four districts of the Eastern and Southern Region of Cameroon. We used indices of significant use and performance applied to all mentioned species, alongside searches in the literature. The statistical tools used to distinguish the different groups/districts is Pearson’s X2 test. A total of 378 plant species were identified of 270 genera and 85 families. Ethnobotanical indices allowed to identify the most confirmed and efficient plants for several health problems. A pairwise comparison of these indices showed a significant correlation with a p-value < 2.2e-16 and a dissimilarity distance less than 0.5. Some plants selected are widely cited in other regions and/or countries for the same health problems. The presence of active molecules responsible for their biological activity was also proven, justifying their use in traditional medicine. This paper examines the potential to enhance the value of Cameroon’s pharmacopeia by integrating various ethnobotanical indices. It aims to discover new therapeutic molecules and develop improved traditional products from the diverse plant species documented. The findings indicate opportunities to advance both local and global healthcare solutions.

关键词： Confirmed Plants Import-Substitution Improved Traditional Medicine (ITM) Sustainable Development Goals Therapeutic Molecules

Management of Retroperitoneal Liposarcoma: A Case Report

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Surgical Science 2016年第8期7卷 361-367页

作者： Joseph Yorke Pius Agbenorku Roland Awoonor-Williams michael Offoe Adinku Eseenam Anita Agbeko Joseph Yaw Manu Kodwo Aboagye Addae Papa Kwesi Sonsomir Fiifi Yankson Dorcas Ahulu Daniel Anning Gyawu nana Esi Abeduwa Abaidoo Dennis Afful-Yorkee Department of Surgery School of Medical Sciences College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana Directorate of Anaesthesia and Intensive Care Komfo Anokye Teaching Hospital Kumasi Ghana Reconstructive Plastic Surgery & Burns Unit Department of Surgery School of Medical Sciences College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana General Surgery Unit Directorate of Surgery Komfo Anokye Teaching Hospital Kumasi Ghana School of Medical Sciences College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana

Retroperitoneal liposarcoma is a rare malignant tumour with an incidence of 2.5 per million people annually. It is the most common type of all the retroperitoneal malignant tumours. Early diagnosis of the tumour is difficult because of absence of specific clinical presentation. Symptoms would only occur if the tumour exhibits pressure on the surrounding organs. It usually occurs between the fourth to sixth decades of life affecting both genders equally. Histological subtypes include: well-differentiated, poorly differentiated, myxoid, round cell and pleomorphic. Radiological imaging useful in diagnosis include: ultrasonography, computed tomography and magnetic resonance imaging. Complete surgical resection of the tumour and the adjacent viscera involved or organs remained the mainstay of treatment. Radiotherapy plays a role in reducing the risk of recurrence but its effect on the overall survival of patients is not known. The case presented is a 48-year-old male patient with retroperitoneal liposarcoma, treated by complete surgical resection of the tumour and right hemicolectomy and currently on follow-up for possible recurrence.

关键词： Retroperitoneal Liposarcoma Surgical Resection Malignant Tumour

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创业邦 2014年第11期 98-98页

作者： michael Hess nana

前段时间,我约见一位员工做中期业绩评估。我挺兴奋,因为我准备给她个大惊喜——大幅加薪以回馈她担负额外责任的辛劳。对企业主而言,给员工加薪是（至少应该是）最愉快的事之一,我整个星期都在期待这一刻的到来。评估结束后我告诉了她... 详细信息

前段时间,我约见一位员工做中期业绩评估。我挺兴奋,因为我准备给她个大惊喜——大幅加薪以回馈她担负额外责任的辛劳。对企业主而言,给员工加薪是（至少应该是）最愉快的事之一,我整个星期都在期待这一刻的到来。评估结束后我告诉了她新的薪资水平,她却面无表情地回复道：＂我以为早该加薪了。＂

关键词：薪资水平复道业绩评估最佳决策对我说现金流警兆现金损失细微差别我自己