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High Capacity Spectrum Sensing Framework Based on Relay Cooperation

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China Communications 2016年第8期13卷 117-126页

作者： Wu Xuanli Han Xingling fabrice Labeau School of Electronic and Information Engineering Harbin Institute of Technology Harbin 150001 China Department of Electrical and Computer Engineering McGill University Quebec Canada

In order to reduce interference to primary users and provide better performance of detection probability and channel capacity in multi-user cooperative spectrum sensing networks, a high capacity spectrum sensing framework is proposed based on the analysis of amplification factors on the performance of detection probability and channel capacity. Thanks to the energy concentration property of chirp signals in the Fractional Fourier Transform(Fr FT) domain, sinusoidal signal and different chirp signals are utilized for primary user and cognitive users, respectively. Hence, spectrum sensing and signal transmission can be performed simultaneously in our proposed framework. Simulation results show that compared with the previous relay-based framework, the modified cooperative spectrum sensing framework can improve the detection probability significantly, and the channel capacity can also be improved. Moreover, the amplification factor can be used to realize the tradeoff between detection probability and channel capacity in our proposed framework.

关键词： cognitive radio cooperative spectrum sensing energy detection detection probability channel capacity

The biosorption of Cr（VI） ions by dried biomass obtained from a chromium-resistant bacterium

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 454-464页

作者： Paul fabrice NGUEMA Zejiao LUO Jingjing LIAN State Key Laboratory of Biogeology and Environmental Geology Ministry of Education (BGEG) School of Environmental Studies China University of Geosciences Wuhan 430074 China Schools of Earth Environment and Water Resources Yangtze University Wuhan 430100 China

The biosorption potential of many different kinds of biomaterials has been widely studied. However, there is little data on the biosorption mechanism of Cr（VI） by dried biomass. So the bio-removal of Cr（VI） ions from aqueous solutions was investigated using dried biomass from a chromium-resistant bacterium. The bacterium was isolated from dewatered sludge samples that were obtained from a sewage treatment plant. Equilibrium and kinetic experiments were performed at different metal concentra- tions, pH values, and biosorbents dosages. The biomass was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The functional groups in the Bacillus cereus biomass which may play a role in the biosorption process were identified by Fourier transform infrared spectroscopy. The biosorption process was found to be highly pH dependent and the optimum pH for the adsorption of Cr（VI） was 2.0：k0.3 at 30-4-2 ℃. The experimental data fit well with Langmuir and Freundlich models as well as a pseudo-second order kinetic model. The mechanism for the biosorption was also studied by fitting the kinetic data with an intra-particle diffusion model and a Boyd plot. External mass transfer was found to be the rate-determining step for the adsorption process. Biosorption could be an alternative mechanism besides bio-oxidation and bio-reduction for the bioremediation of heavy metals.

关键词： Bacillus cereus Pf-1 biosorption capacity,biosorbents Cr(VI) biomass

On the use of 1g physical models for ground movements and soil-structure interaction problems

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 197-211页

作者： Marwan Al Heib fabrice Emeriault Huu-Luyen Nghiem INERIS Parc technologique AlataVemeuil-En-HalatteF-60550France Universite Grenoble Alpes 3SRGrenobleF-38000France CNRS 3SRGrenobleF-38000France

The paper focusses on the use of physical modelling in ground movements(induced by underground cavity collapse or mining/tunnelling)and associated soil-structure interaction *** paper presents first an overview of using 1 g physical models to solve geotechnical problems and soil-structure interactions related to vertical ground *** the lg physical modelling application is illustrated to study the development of damage in masonry structure due to subsidence and cavity collapse.A largescale 1 g physical model with a 6 m^3 container and 15 electric jacks is presented with the use of a threedimensional(3D)image correlation *** influence of structure position on the subsidence trough is analysed in terms of crack density and damage *** obtained results can improve the methodology and practice for evaluation of damage in masonry ***,ideal physical model is difficult to ***,future improvement of physical models(analogue materials and instrumentation)could provide new opportunities for using 1 g physical models in geotechnical and soilstructure applications and research projects.

关键词： Subsidence Physical modelling Geotechnical problems Soil-structure interaction

Laparoscopic Appendectomies at Brazzaville University Hospital

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Surgical Science 2024年第4期15卷 183-194页

作者： Murielle Etiennette Julie Note Madzele Pierlesky Elion Ossibi Bhodeho Medi Monwongui Didace Massamba Miabaou Giresse Bienvenu Tsouassa Wa Ngono Prude Pertinie Avala Gilles Niengo Outsouta Noé Henschel Motoula Latou Carmich Nzaka Moukala Cédrick Du Bonheur Alima Koya Gilbert fabrice Otiobanda Digestive Surgery Department Brazzaville University Hospital Brazzaville Republic of the Congo Faculty of Health Sciences Marien Ngouabi University Brazzaville Republic of the Congo General Intensive Care Unit Brazzaville University Hospital Brazzaville Republic of the Congo

Introduction: Acute appendicitis represents an urgent surgical condition, requiring the removal of the vermiform appendix. Laparoscopy is the standard surgical approach. This study aimed to outline the epidemiological, clinical, therapeutic, and outcome characteristics of patients undergoing laparoscopic surgery for acute appendicitis. Patients and Methods: A descriptive, retrospective analysis was carried out in the Emergency and Digestive Surgery departments of the University Hospital Center of Brazzaville, spanning two years from January 1, 2021, to December 31, 2022. The study included all patients who underwent laparoscopic surgery for non-complicated acute appendicitis. Results: The study included 12 cases of non-complicated acute appendicitis treated with urgent laparoscopy. The mean age of the patients was 37 ± 8.9 years, with a sex ratio of 0.7. The predominant symptom leading to consultation was pain in the right iliac fossa, with an average time to consultation of 6.4 ± 5.7 hours. Patient histories included diabetes in one case, obesity in two cases, and one case of prior abdominoplasty. During surgery, a phlegmonous appendix was observed in nine patients. The average duration of hospital stay was 3.6 ± 1.3 days, with all patients experiencing uncomplicated recoveries. Conclusion: The practice of emergency laparoscopic appendectomy is still relatively infrequent in our setting and presents an ongoing challenge.

关键词： Acute Appendicitis Appendectomy Laparoscopy Emergency

Effect of Biostimulants Based on Natural Products on the Growth and Nutritional Value of Bean (Phaseolus vulgaris L.)

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American Journal of Plant Sciences 2024年第7期15卷 492-518页

作者： Aimé Giresse Tzeuton Flore Eliane Eyenga Arouna Meshuneke Gaston Mbang Elock fabrice Damien Wassom Walter Jospin Timma Kom Marie Paule Djam Kengoum Erica Cabrelle Damtse Damtse Landry Silatsa Fotsing William Asah Che Marlyne Josephine Mananga Nicolas Niemenak Cécile Annie Ewané Laboratory of Plant Physiology and Biochemistry Higher Teachers Training College University of Yaound 1 Yaound Cameroon Department of Biochemistry Faculty of Sciences University of Yaound 1 Yaound Cameroon Laboratory of Food Sciences and Metabolism University of Yaoundé 1 Yaoundé Cameroon Laboratory of Phytoprotection and Valorisation of Genetic Resources of the Biotechnology Centre University of Yaound 1 Yaound Cameroon Department of Biological Sciences Higher Teachers Training College University of Yaound 1 Yaound Cameroon

Beans (Phaseolus vulgaris L.) are widely grown in Cameroon and play a key role in the fight against food insecurity, malnutrition and poverty. However, its cultivation encounters problems due to abiotic and biotic stresses, which leads to the use of synthetic fertilizers and pesticides, which cause significant damage to the environment and human health due to the presence of synthetics residues in the seeds, pods and in the leaves that are eaten. Promoting the use of natural products is becoming a necessity for organic and eco-responsible agriculture that limits contamination problems and improves people’s purchasing power. This study aims to assess the effect of biostimulants based on natural products on the growth and nutritional value of common bean (Phaseolus vulgaris L.). Bean seedlings from white variety (MEX-142) and red variety (DOR-701) were treated every seven days in the field from their pre-emergence, emergence and growth to their maturation under a randomized block experimental design. Six treatments and three repetitions with the biostimulants based on natural products and controls were thus performed and the agromorphological parameters were measured. After 120 days, the contents of growth biomarkers and defense-related enzymes were evaluated in leaves, while the contents of macromolecules, minerals and antinutrients were evaluated in seeds. These biostimulants significantly increased (P P < 0.0001) of antinutrients including oxalates, phytates, tannins and saponins in seeds compared to controls (T+ and T−). Treatment with biostimulants, in particular BS4, improves the performance of bean plants in the field as well as the biofortification of seeds regardless of the variety.

关键词： Phaseolus vulgaris L. Biostimulants Biofortification Growth and Defense Biomarkers Nutritional Value

Rib Osteosynthesis for Sub-Acute Management of a Flail Chest in a Tertiary Centre in a Low-Middle Income Country of Sub-Saharan Africa: Case Report at Douala Laquintinie Hospital

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Open Journal of Thoracic Surgery 2024年第1期14卷 1-16页

作者： fabrice Stéphane Arroye Betou Nyankoue Mebouinz Ferdinand Guy Aristide Bang Kobe Folkabo Zephany Banga Nkomo Douglas Moussa Seck Diop Abdoul Lahad Mbeng Marcella Derboise Christelle Biyouma Noel Essomba Souleyman Diatta Handy Eone Daniel Arthur Essomba Hassan Ndiaye Maurice Aurelien Sosso Department of Surgery and Specialties Faculty of Medicine and Biomedical Sciences (FMBS) University of Yaoundé (UYI) Yaoundé Cameroon Department of Surgery and Affiliated Disciplines Douala Laquintinie Hospital Douala Cameroon Department of Surgery and Specialties Yaoundé General Hospital Yaoundé Cameroon Department of Surgery and Specialties Faculty of Medicine and Pharmaceutical Sciences (FMPS) University of Dschang Dschang Cameroon Service de Chirurgie Thoracique et Cardiovasculaire Centre Hospitalier Universitaire de Fann Faculté de Médecine de Pharmacie et d’Odontologie Université de Cheikh Anta Diop Dakar Sénégal UFR des Sciences de la Santé Ziguinchor Sénégal

Background: Costal fracture surgical is still a debate, therefore we shall select between early and delay surgical management. Case Report: We are reporting two cases of post road traffic clash delay ribs fractures osteosynthesis involving a 63-year-old man with multistage fractures on the left and pulmonary pinning of one of the costal arches, complicated by a homolateral haemothorax and a 41-year-old man with a bilateral flail chest. Conclusion: The simple postoperative course and the immediate postoperative improvement in the patient’s clinical respiratory condition enabled us to discuss the time frame for management, in this case the indication for early or later surgery.

关键词： Flail Chest Fixation Plate Rib Fracture Osteosynthesis

Estimation of the Lyman-α signal of the EFILE diagnostic under static or radiofrequency electric field in vacuum

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Plasma Science and Technology 2018年第7期20卷 1-6页

作者： Carlo POGGI Theo GUILLAUME fabrice DOVEIL Laurence CHIERIGIER-KOVACIC Consorzio RFX Corso Stati UnitiI-35127 PadovaItaly Aix-Marseille Universite CNRSPIIM UMR 7345F-13397 Marseille Cedex 20France

The electric field induced Lyman-a emission diagnostic aims to provide a non intrusive and precise measurement of the electric field in plasma, using a beam of hydrogen atoms prepared in the metastable 2s state. The metastable particles are obtained by means of a proton beam extracted from a hydrogen plasma source, and neutralised by interaction with vaporised caesium. When a 2s atom enters a region where an electric field is present, it undergoes a transition to the 2p state （Stark mixing）. It then quickly decays to the ground level, emitting Lyman-a radiation, which is collected by a photomultiplier. The 2s → 2p transition rate is proportional to the square of the magnitude of the electric field, and depends on the field oscillation frequency （with peaks around l GHz）. By measuring the intensity of the Lyman-a radiation emitted by the beam it is possible to determine the magnitude of the field in a defined region. In this work, an analysis of the behaviour of the diagnostic under static or radiofrequency electric field is presented. Electric field simulations obtained with a finite element solver of Maxwell equations, combined with theoretical calculations of the Stark mixing transition rate, are used to develop a model for the interpretation of photomultiplier data. This method shows good agreement with experimental results for the static field case, and allows to measure the field magnitude for the oscillating case.

关键词： electric field measurement electromagnetic simulations Stark effect plasma diagnostics

Stimulatory Effect of Tithonya diversifolia-by Products on Plantain Banana Vivoplants in Nursery (A Review)

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American Journal of Plant Sciences 2024年第9期15卷 726-745页

作者： Cécile Annie Ewané Arouna Meshuneke Gaston Elock Mbang fabrice Damien Wassom William Asah Che Glen Takang Beyang Craftsman Ndula Ndula-Nan Landry Fotsing Silatsa Jospin Walter Kom Timma Marie-Paule Kengoum Djam Rosine Arckange Barakielle Bindzi Abah Nicolas Niemenak Department of Biochemistry Faculty of Science University of Yaounde 1 Yaounde Cameroon Laboratory of Biochemistry and Vegetal Physiology of Higher Teachers Training College University of Yaounde 1 Yaounde Cameroon Laboratory of Phytoprotection and Valorisation of Genetic Resources of The Biotechnology Centre University of Yaounde 1 Yaounde Cameroon Department of Biological Science Higher Teachers Training College University of Yaounde 1 Yaounde Cameroon

Plantain banana is an important cash crop that serves as stable food for millions of people around the world and contributes to income generation. Indeed, they provide a major staple food crop for millions of people and play an important role in the social fabric of many rural communities. Plantain banana cultivation encounters major problem of seedlings unavailability that are essential for the creation of new plantations, as well as parasitic constraints. Mycosphaerella fijiensis is the main pathogen attack constraints of banana plant responsible of black Sigatoka disease, and viruses, which can severely reduce the photosynthetic leaf area, leading to banana production losses of more than 80% in plantations with soil fertility problems. The repeated use of synthetic input is the origin of contamination to the environment, different pollution sources of plants and human health, as well as resistance to some strains of pathogens and plant fertilization problems over time. Recent works carried out in nursery have shown that vivoplants of plantains treated with biostimulants based on natural products notably Tithonia diversifolia biopromote good growth and less susceptibility to M. fijiensis. Indeed, an increase in agromorphological characteristics, good accumulation of growth and defense biomarkers was also observed. In this context, Tithonia diversifolia is shown to be involved in the stimulatory effect mechanism of growth promotion and defensive reaction of plantain vivoplants against various pathogens and it is suggested to be acting as a vital stimulator. This article reviews the current state of knowledge on plantain banana cultivation constraints and on the potential of Tithonia diversifolia in relation with its different stimulatory effects on plantain vivoplants.

关键词： Tithonia diversifolia Plantain Banana Black Sigatoka Disease Growth Biopromotion Bioprotection Induced Resistance Biofungicidal Effect

Observation of supersymmetric pseudo-Landau levels in strained microwave graphene

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Light(Science & Applications) 2020年第1期9卷 611-617页

作者： Matthieu Bellec Charles Poli Ulrich Kuhl fabrice Mortessagne Henning Schomerus Institut de Physique de Nice(INPHYNI) Universite Cote d’AzurCNRS06108 NiceFrance Department of Physics Lancaster UniversityLancaster LA14YBUK

Using an array of coupled microwave resonators arranged in a deformed honeycomb lattice,we experimentally observe the formation of pseudo-Landau levels in the whole crossover from vanishing to large pseudomagnetic field *** result is achieved by utilising an adaptable setup in a geometry that is compatible with the pseudo-Landau levels at all field *** adopted approach enables us to observe the fully formed flat-band pseudo-Landau levels spectrally as sharp peaks in the photonic density of states and image the associated wavefunctions spatially,where we provide clear evidence for a characteristic nodal structure reflecting the previously elusive supersymmetry in the underlying low-energy *** particular,we resolve the full sublattice polarisation of the anomalous 0th pseudo-Landau level,which reveals a deep connection to zigzag edge states in the unstrained case.

关键词： microwave strained Landau