143 research outputs found
The Anglophone Problem in Cameroon: Political Representation and Socio-Economic Development
Minority group conflicts and marginalization has been a challenge to the peaceful existence and development of many African countries. This thesis is based on the topic: The Anglophone problem: Political representation and Socio-economic development. Cameroon is the case since its independence in 1960 till date. The Anglophones who form the minority claim they are marginalized by the Francophones who are the majority and the ruling group. They claim that they are not politically represented both in the Government and in decision making of the country, and also their regions, the Northwest and Southwest Provinces lag behind both in social and economic development. The origin of the Anglophone problem and ways in which the Anglophones are being marginalized is an important part of this thesis and is being looked at. Attention is also focused on what the Anglophone movements like the SCNC, AAC, and the SCYL have been doing to stop the marginalization of the Anglophones and the response of the Cameroonian Government to provide a solution to the problem. Theories based on Ethnicity, Political systems and Regional development based on social and economic development will be used to analyze the empirical material. In addition analysis of course and related literature on Cameroon will be the methodology used because of the inability to undertake field research. It is hoped that this work will contribute to a framework on which peace and development organizations can rely in the fight against minority conflict and poverty in Cameroon and Africa as a whole
Liberiaâs postwar constitution review: A tale of mistrust and uncertainty
Richard Akum and Mainlehwon Vonhmassess the proposals under consideration in Liberiaâs constitution review. This post is part of our African Elections series
BIMBINGAN TEKNIS PENGGUNAAN MIKROSKOP UNTUK MENINGKATKAN KETERAMPILAN PROSES SAINS SANTRI DI PONDOK PESANTREN DARUL AZHAR ACEH TENGGARA
This PKM technical guidance was carried out at the Darul Azhar Aceh Tenggara Islamic boarding school on Thursday, January 19 2023. All class VII students werw targeted and this activity was carried out using the ecplicit instruction method (direct teaching). Most of the students at the Darul Azhar Aceh Tenggara Islamic boarding svhol have a basic understanding of microscope increases significantly after the introduction and practice of microscopy. Only 20% of students in demonstrating being able to understand microscopy. After this activity was carried out there was an increase, namely 90% of class VII students were able to understand the use of a microscope.
Keywords: technical guidance, microscopy, process skills, scienc
Counting colorings of triangle-free graphs
By a theorem of Johansson, every triangle-free graph of maximum degree
has chromatic number at most for some
universal constant . Using the entropy compression method, Molloy proved
that one can in fact take . Here we show that for every , the number of proper -colorings of
satisfies ,
where and . Except for the term, this lower
bound is best possible as witnessed by random -regular graphs. When , our result yields the inequality , which improves
an earlier bound of Iliopoulos and yields the optimal value for the constant
factor in the exponent. Furthermore, this result implies the optimal lower
bound on the number of independent sets in due to Davies, Jenssen, Perkins,
and Roberts. An important ingredient in our proof is the counting method that
was recently developed by Rosenfeld. As a byproduct, we obtain an alternative
proof of Molloy's bound using
Rosenfeld's method in place of entropy compression.Comment: 16 p
Mechanism and synchronicity of wheat (Triticum aestivum) resistance to leaf rust (Puccinia triticina) and Russian wheat aphid (Duiraphis noxia) SA1
Wheat (Triticum aestivum and T. Durum) is an extremely important agronomic crop produced worldwide. Wheat consumption has doubled in the last 30 years with approximately 600 million tons consumed per annum. According to the International Maize and Wheat Improvement Center, worldwide wheat demand will increase over 40 percent by 2020, while land as well as resources available for the production will decrease significantly if the current trend prevails. The wheat industry is challenged with abiotic and biotic stressors that lead to reduction in crop yields. Increase knowledge of wheatâs biochemical constitution and functional biology is of paramount importance to improve wheat so as to meet with this demand. Pesticides and fungicides are being used to control biotic stress imposed by insect pest and fungi pathogens but these chemicals pose a risk to the environment and human health. To this effect, there is re-evaluation of pesticides currently in use by the Environmental Protection Agency, via mandates of the 1996 Food Quality Protection Act and those with higher perceived risks are banned. Genetic resistance is now a more environmental friendly and effective method of controlling insect pest and rust diseases of wheat than the costly spraying with pesticides and fungicides. Although, resistant cultivars effectively prevent current prevailing pathotypes of leaf rust and biotypes of Russian wheat aphid from attacking wheat, new pathotypes and biotypes of the pathogen/pest may develop and infect resistant cultivars. Therefore, breeders are continually searching for new sources of resistance. Proteomic approaches can be utilised to ascertain target enzymes and proteins from resistant lines that could be utilised to augment the natural tolerance of agronomically favourable varieties of wheat. With this ultimate goal in mind, the aim of this study was to elucidate the mechanism and synchronicity of wheat resistance to leaf rust (Puccinia triticina) and Russian wheat aphid (Duiraphis noxia) SA1. To determine the resistance mechanism of the wheat cultivars to leaf rust infection and Russian wheat aphid infestation, a proteomics approach using two-dimensional gel electrophoresis was used in order to determine the effect of RWA SA1 on the wheat cultivars proteome. Differentially expressed proteins that were up or down regulated (appearing or disappearing) were identified using PDQuestTM Basic 2-DE Gel analysis software. Proteins bands of interest were in-gel trypsin digested as per the protocol described in Schevchenko et al. (2007) and analysed using a Dionex Ultimate 3000 RSLC system coupled to an AB Sciex 6600 TripleTOF mass spectrometer. Protein pilot v5 using Paragon search engine (AB Sciex) was used for comparison of the obtained MS/MS spectra with a custom database containing sequences of Puccinia triticina (Uniprot Swissprot), Triticum aestivum (Uniprot TrEMBL) and Russian wheat aphid (Uniprot TrEMBL) as well as a list of sequences from common contaminating proteins. Proteins with a threshold of â„99.9 percent confidence were reported. A total of 72 proteins were putatively identified from the 37 protein spots excised originating from either leaf rust or Russian wheat aphid experiments. Sixty-three of these proteins were associated with wheat response to stress imposed by RWA SA1 feeding while 39 were associated with infection by Puccinia triticina. Several enzymes involved in the Calvin cycle, electron transport and ATP synthesis were observed to be differentially regulated suggesting greater metabolic requirements in the wheat plants following aphid infestation and leaf rust infection. Proteins directly associated with photosynthesis were also differentially regulated following RWA SA1 infestation and P
Functional characterization of an effector candidate of the root colonizing fungus Piriformospora indica during interaction with plants
Plants have evolved a sophisticated two-layered immune system to protect themselves from microbial invaders. However, in order to promote infection, plant associated microbes including pathogens as well as mutualists secrete molecules called effectors to suppress the plantÂs immune response. Mutualistic fungi including the arbuscular mycorrhiza (AM) Glomus intraradices and the ectomycorrhiza (ECM) Laccaria bicolor secretes effector proteins which contribute to the establishment and maintenance of mutualistic symbiosis by suppressing host immunity during root colonization.
The root endophytic fungus, Piriformospora indica is capable of colonizing the roots of a wide variety of different plant species including the monocot barley (Hordeum vulgare) and the dicot Arabidopsis thaliana and establishes mutualistic symbiosis during colonization. The colonization pattern of P. indica is mainly divided into two phases, an initial biotrophic phase and a later cell death-associated colonization phase. Colonization by the fungi which is mostly limited to the root cortex cells leads to several beneficial effects to the host such as growth promotion, increased resistance to biotic and abiotic stresses. The recently released genome of P. indica helped to identify hundreds of small secreted proteins (SSPs) coding for candidate effectors and provides an opportunity to investigate the role of these effectors during the interaction between this endophytic fungus with plants. It has been reported that P. indica actively suppresses PTI to colonize and establish a mutualistic relationship with plants. However, the deployment of effectors and their role during the interaction of P. indica with plants has not been reported.
In this study, PIIN_08944, an effector candidate of P. indica was functionally characterized in- planta. PIIN_08944 encode a 120 amino acid protein with a predicted 23 amino acid N-terminal signal peptide. Expression profile analysis revealed that PIIN_08944 was induced in in-vitro germinated P. indica chlamydospore as well as in-planta during colonization of Arabidopsis roots by P. indica. To investigate the functional role of PIIN_08944 in mutualistic symbiosis, transgenic P. indica with reduced production or complete loss of PIIN_08944 were generated. RNAi silencing as well as deletion of the gene coding for PIIN_08944 by homologous recombination resulted in delayed colonization of Arabidopsis roots by P. indica. On the hand transgenic Arabidopsis and barley plants expressing PIIN_08944 show enhanced colonization by P. indica compared to wild type. Heterologous expression of PIIN_08944 in barley suppresses flg22 and chitin triggered ROS production. Meanwhile expression of PIIN_08944 in Arabidopsis interfered with the transcription of marker genes for PTI, AtWRKY22 and salicylic acid, CBP60g. However, the expression of PIIN_08944 in Arabidopsis and barley did not affect the plantÂs response to the necrotrophic fungal pathogens Botrytis cinerea and Fusarium graminearum respectively. Yeast two hybrid screen revealed that PIIN_08944 interacts with CSN5A and CSN5B, components COP9 signalosome protein complex, in Arabidopsis and N. benthamiana and with SINA3, a member of the SEVEN IN ABSENTIA family of E3 protein ligase in tobacco. Subcellular localization assays performed on N. benthamiana leaves revealed that CSN5A, CSN5B and PIIN_08944 localized to the nucleus and cytoplasm. In summary, the fact that PIIN_08944 targets the evolutionarily conserved eukaryotic proteins, CSN5A and CSN5B and interfere with basal defense, indicate that P. indica has evolved strategies involving the use of effectors as general compatibility determinants to establish and/or maintain a mutualistic relationship during interaction with plants. Moreover, this might further explain the capability of P. indica to colonize a multitude of different plant species.Pflanzen haben im Laufe der Evolution ein zweischichtiges Immunsystem entwickelt, um sich von mikrobiellen Eindringlingen zu schĂŒtzen. Auf der anderen Seite können Mikroben einschlieĂlich Krankheitserreger sowie Mutualisten so genannte Effektor-MolekĂŒle sekretieren, um eine Infektion zu fördern und eine Immunantwort der Pflanze zu unterdrĂŒcken. Mutualistische Pilze, einschlieĂlich der arbuskulĂ€ren Mykorrhiza (AM) Glomus intraradices und der Ektomykorrhiza (ECM) Laccaria bicolor, sekretieren Effektor-Proteine, um WirtsimmunitĂ€t bei Wurzelbesiedlung zu underdrĂŒcken und somit dienen diese Effektoren zur Etablierung und dem Erhalt der mutualistischen Symbiose.
Der Wurzel endophytische Pilz Piriformospora indica ist fĂ€hig Wurzeln einer Vielzahl von verschiedenen Pflanzenarten, einschlieĂlich der monokotylen Gerste (Hordeum vulgare) und dem zweikeimblĂ€ttrigen Arabidopsis thaliana, zu kolonisieren und etabliert eine mutualistischen Symbiose. Die Besiedlung Strategie von P. indica wird hauptsĂ€chlich in zwei kolonisierungs Phasen unterteilt. Einer ersten biotrophen und einer spĂ€teren Zelltod-assoziierten Phase. Die Kolonisierung durch den Pilz, die meist auf die Wurzel Cortex Zellen begrenzt ist, fĂŒhrt zu mehreren positiven Effekten auf den Wirt, wie Wachstumsförderung und erhöhte Resistenz gegen biotische und abiotische Stressfaktoren. Das kĂŒrzlich veröffentlichte Genom von P. indica zeigte hunderte von kleinen sekretierten Proteine (SSP), welche Effektor Kandidaten kodieren. Dies bietet die Möglichkeit, die Rolle dieser Effektoren bei der Interaktion zwischen endophytischen Pilz und Wirtspflanze zu untersuchen. Es wurde bereits berichtet, dass P. indica aktiv PTI unterdrĂŒckt um den Wirt zu kolonisieren. Allerdings ist der genaue Einsatz der Effektoren und deren Rolle bei der Wechselwirkung zwischen P. indica und den Wirtspflanzen noch nicht bekannt.
In dieser Studie wurde der Effektor Kandidat von P. indica PIIN_08944 funktionell in- planta charakterisiert. PIIN_08944 kodiert ein 120 AminosĂ€uren langes Protein mit einem prognostizierten 23 AminosĂ€uren N-terminales Signalpeptid. Expressionsanalysen ergaben, dass in vitro PIIN_08944 in gekeimten P. indica Chlamydospore sowie in planta wĂ€hrend der Kolonisation von Arabidopsis Wurzeln, erhöht induziert ist. Um die FunktinalitĂ€t des PIIN_08944 in der mutualistischen Symbiose zu untersuchen, wurde transgener P. indica mit reduzierten Produktions oder vollstĂ€ndigen Verlust des PIIN_08944 hergestellt. RNAi-Silencing sowie Deletion von PIIN_08944 gene durch homologe Rekombination fĂŒhrte zu einer verzögerten Besiedlung von P. indica an Arabidopsis Wurzeln. Auf der anderen Seite zeigen transgene Arabidopsis und Gerste Pflanzen, die PIIN_08944 exprimieren, verbesserte Besiedlung mit P. indica im Vergleich zum Wildtyp. Die heterologe Expression von PIIN_08944 in Gerste unterdrĂŒckt flg22- und Chitin- ausgelöste ROS-Produktion. Wohingegen Expression von PIIN_08944 in Arabidopsis suppremiert die Transkription von Markergenen fĂŒr PTI, AtWRKY22 und SalicylsĂ€ure, CBP60g. Die Expression von PIIN_08944 in Arabidopsis und Gerste hatte jedoch keinen Einfluss auf die Verteidigungsantwort der Pflanze gegen die nekrotrophen Pilzerreger Botrytis cinerea und Fusarium graminearum. Yeast two hybrid Screening ergab, dass PIIN_08944 mit CSN5A und CSN5B Komponent COP9 Signalosom Proteinkomplex, in Arabidopsis und N. tabaccum und mit SINA3, ein Mitglied der SEVEN IN ABSENTIA Familie E3-Protein-Ligase, in Tabak interagiert. SubzellulĂ€re Lokalisierungs assays an N. benthamiana BlĂ€ttern zeigten eine Lokalisation von CSN5A, CSN5B und PIIN_08944 im Zellkern und im Cytoplasma. Zusammenfassend zeigt diese Studie, dass PIIN_08944 als Effektor auf die evolutionĂ€r konservierte eukaryotischen Proteinen, CSN5A und CSN5B abzielt und somit die basale Abwehr der Wirtspflanze stört. Dadurch wird gezeigt, dass P. indica Effektoren als allgemeine KompatibilitĂ€ts Determinanten zur Etablierung und / oder zum Erhalt einer mutualistischen Beziehung innerhalb der Interaktion mit Pflanzen gebraucht. AuĂerdem könnte dies erlĂ€utern, wie es P. indica befĂ€higt eine Vielzahl von verschiedenen Pflanzenarten zu besiedeln
Diseño del sistema de mandos de vuelo para una cabina de DC9
This Project develops the design and implementation of a mechanical and electronic flight controls system, to enable a flight simulation in a real McDonell Douglas DC-9-34 cabin using the real airplane flight controls. At first are shown the objectives and requirements to be achieved with the project implementation. Then it is performed an study of the airplane to know more about the real flight controls operation, which are inoperative for having only the front fuselage section. Being a project with a practical part, the working environment develops in the fuselage, therefore the different workspaces are described. The current airplane condition and flight control mechanical systems are analized before starting design development. The design of the new system is based on two characteristic points for theoretical development. The data acquisition point, corresponding to mechanical part ant the sensor that performs reading of data system, corresponding to electronic part. With the previous analysis of the aircraft, choosing the data acquisition point and sensor type, the final design is developed to use like a roadmap for practice implementation in the airplane. At last describe in detail the implementation process of the new flight control system in the airplane. The movement transmission of cabin flight controls is done with mechanical control cable system, this is the movement data acquisition point of flight controls. Data sensing of cable system movement is done with a potentiometer sensor. Then the output signal of sensors may be transformed and adapted for use in a flight simulation
Informal ordering, authority and control: borderland dynamics and postwar statebuilding in Liberia
Sharing Dreams, Strengthening Visions: The Right to Self-Determination as a Resource for JustPeace
The question of self-determination has re-entered the center stage of world affairs in the 21st century. While the right of self-determination in the 20th century was for most part clothed in legal language and reduced to a privilege of 'State-determination,' the events that the world has witnessed in Kosovo, South Sudan, Egypt, Libya, Burma, Syria over the last ten years indicate the peoples' increasing desire to recover their self-determining capacities. These emerging trends have created conditions for the 21st century to be a century of 'peoples-determination' that is based on their values, dreams and imagination. The primary reason for this research study comes from the awareness that an unrepresented peoples' perspective is largely missing from existing literature on self-determination affecting their future. This research will strengthen it by providing a perspective that critically analyzes the State system which has denied the right to self-determination of all peoples. This denial has been the source of protracted and violent conflicts; and by equating the language of self-determination to secession and State sovereignty, it has affectively reduced the capacity of self-determination as a resource for JustPeace
Evaluation of the quality of the communication and emotional support during the donation procedure : the use of the donor family questionnaire (DFQ)
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