Developing Optical Coherence Tomography for the Quantitative Study of Erosive and Carious Lesions in Dental Enamel in vitro

PhDOptical Coherence Tomography (OCT) is an imaging technique that uses near infra-red light to non-invasively form cross-sectional images of specimens, in a similar way to ultrasound and RADAR. A number of research groups have used OCT to study natural and artificial carious lesions and to some extent erosive lesions. For this, a variety of in vitro models have been used. However, the exact mechanism by which these demineralised enamel lesions affect the OCT measurements is not fully understood. This remains a barrier to its adoption as both an analytical laboratory tool and a widespread technique in clinical dentistry. Therefore, the aim of this thesis was to develop an understanding of how different demineralised enamel lesions manifest in OCT measurements. This is necessary for the technique to become useful as an in vivo clinical measurement and imaging system. Consequently, this study was carried out in a controlled laboratory environment for which a novel specimen holder was designed. This mitigated against specimen movement and maintained specimen hydration, which can be a source of uncertainty in the measurements. A custom-built OCT microscope was used for this work, which enabled automation of experiments and continuous time-lapse OCT imaging over time periods of hours to several days. This enabled bovine enamel demineralisation dynamics to be captured during in vitro caries and erosion formation. The stability of the system also enabled direct comparison between the OCT measurements of the optical properties of different demineralisation models. To achieve these measurements, the OCT system was carefully characterised and compared to established profilometry measurements. Interestingly, this revealed that the experimental protocol used to obtain lesions for profilometry was not to be representative of the lesions formed and measured by OCT. This is an important point when interpreting OCT data in light of other techniques. A novel method of analysis was developed that uses longitudinal OCT image correlation to quantify early stage surface softening during erosion. By using OCT volumetric data, this technique was able to measure sub-resolution changes at the specimen surface. Early results also indicate sensitivity to remineralisation. This thesis shows that OCT is sensitive to different demineralisation models produced and measured under controlled conditions. New method of handling the data can observe changes not previously seen in OCT. However, further work is still required to understand the underlying physical changes that lead to this sensitivity in OCT.BBSRC and GSK - BBSRC Industrial CASE award BB/K501190/1)

Review the role of transovarial transmission by mosquitoes and wildlife circulation in the persistence of Rift Valley fever virus

Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic viral disease affecting domestic and wild animals as well as humans, primarily in Africa and the Arabian Peninsula, with a proven ability to emerge in new geographic areas. Despite its importance, the mechanisms for maintaining RVFV between epidemics remain unclear. This review highlights the vertical transmission of the virus in mosquitoes, the role of wildlife as a reservoir host and the impact of climate change on disease outbreaks. Field and laboratory studies show that RVFV is primarily maintained by transovarial virus transmission in mosquitoes, while wildlife, particularly ruminants, acts as a reservoir during inter-epidemic periods. Climate change promotes outbreaks by increasing populations of RVFV vectors, particularly Aedes mosquitoes, in areas where heavy precipitation, flooding and high temperatures provide conditions for infected mosquitoes to multiply

Progress and experiences of implementing an integrated disease surveillance and response system in Somalia; 2016–2023

IntroductionIn 2021, a regional strategy for integrated disease surveillance was adopted by member states of the World Health Organization Eastern Mediterranean Region. But before then, member states including Somalia had made progress in integration of their disease surveillance systems. We report on the progress and experiences of implementing an integrated disease surveillance and response system in Somalia between 2016 and 2023.MethodsWe reviewed 20 operational documents and identified key integrated disease surveillance and response system (IDSRS) actions/processes implemented between 2016 and 2023. We verified these through an anonymized online survey. The survey respondents also assessed Somalia’s IDSRS implementation progress using a standard IDS monitoring framework Finally, we interviewed 8 key informants to explore factors to which the current IDSRS implementation progress is attributed.ResultsBetween 2016 and 2023, 7 key IDSRS actions/processes were implemented including: establishment of high-level commitment; development of a 3-year operational plan; development of a coordination mechanism; configuring the District Health Information Software to support implementation among others. IDSRS implementation progress ranged from 15% for financing to 78% for tools. Reasons for the progress were summarized under 6 thematic areas; understanding frustrations with the current surveillance system; the opportunity occasioned by COVID-19; mainstreaming IDSRS in strategic documents; establishment of an oversight mechanism; staggering implementation of key activities over a reasonable length of time and being flexible about pre-determined timelines.DiscussionFrom 2016 to 2023, Somalia registered significant progress towards implementation of IDSRS. The 15 years of EWARN implementation in Somalia (since 2008) provided a strong foundation for IDSRS implementation. If implemented comprehensively, IDSRS will accelerate country progress toward establishment of IHR core capacities. Sustainable funding is the major challenge towards IDSRS implementation in Somalia. Government and its partners need to exploit feasible options for sustainable investment in integrated disease surveillance and response

Küçük ve Orta Ölçek İşletmelerin (KOBİ) performans göstergelerinin işletmelerin cirosu ekonomik büyümenin bir boyutu olarak üzerindeki etkisini.

Tez (yüksek lisans) - Anadolu ÜniversitesiAnadolu Üniversitesi, Sosyal Bilimler Enstitüsü, Arkeoloji Anabilim DalıKayıt no: 434726Bu çalışma, küçük ve örta ölçek işletmelerin (KOBİ) performans göstergelerinin Borama'daki yerel kaynaklardan daha etkin yararlanmayı ve sosyal ekonomik durumu iyileştirmesi nedeniyle ekonomik büyümenin bir boyutu olarak işletmelerin cirosu üzerindeki etkisini ele almaktadır. Borama'da KOBİ'lerin performansını etkileyen güçlükler, özellikle de hükümetin ve ilgili kurumların politika oluştururken özen göstermedikleri durumlar bu çalışmada ayrıca incelenmiştir. Bu kurumların ülkede bir KOBİ politikası bulunmayışı konusunda hassasiyet göstermedikleri görülmüştür. Finansal sorunlar ve devlet desteğinin olmayışı KOBİ'lerin performansını artırmalarını engelleyerek Borama ekonomisine katkıda bulunmalarını mümkün kılmamaktadır. Bu nedenle, çalışmada belirtilen hususlarla ilgili olarak, Borama'da faaliyet gösteren 211 adet KOBİ'den elde edilen birincil verilerle, performans göstergelerinin ekonomik büyümenin bir boyutu olarak işletmelerin cirosu üzerindeki etkisi araştırılmıştır. Ana değişkenlerin demografik özelikleri, KOBİ'lerin performansı, finansman kaynakları ve karşılaştıkları zorlukları anlayabilmek için tanımlayıcı istatistikler kullanılmıştır. Çalışmada, ana değişkenler arasındaki ilişki yönü ve gücünü belirtilmek için regresyon ve korelasyon analizleri kullanılmıştır. Analiz sonuçları, KOBİ'lerin performans göstergelerinden kârlılık ve girişimciliğin KOBİ'lerin cirosu üzerinde olumsuz etkisi olduğunu göstermektedir. Ayrıca, yatırım, istihdam ve altyapının gelişiminin ise olumlu etkisi bulunduğu görülmüştür. Bu nedenle, çalışmada elde edilen sonuçlardan yola çıkarak devletin Borama'da ve tüm ülkede KOBİ'lerin gelişmesine daha fazla önem vermesi gerekmektedir

TOPLUMSAL KALKINMA BAĞLAMINDA FEDERALİZMİN FIRSAT VE ZORLUKLARI: SOMALİ ÖRNEĞİ

This working paper outlines the opportunities and challenges of federalism and community development in Somalia. In 2004 Somali clan elders and politicians considered adopting federalism as the new system of government and by 2012, Somalia adopted federalism and established four states: Jubaland, Galmudug, Hirshabelle, and the Southwest States, in addition to the previously established states Puntland and Somaliland. This paper focuses on how federalism affects community development in Somalia and identifies opportunities and challenges of federalism for community development. Federalism has offered opportunities with significant improvement in security, economic improvement, a better education system, a healthcare system, power distribution, political stability, and women’s and youth’s empowerment. However, it thus poses challenges which are border conflicts, power disputes, the exploitation of natural resources, and minority injustice. The method used for this research is a survey data analysis.Bu araştırma, Somali’de Federalizmden kaynaklı fırsat ve zorlukların toplumsal kalkınma özelinde incelenmesi hakkında yazılmıştır. 2004'te Somalili klan büyükleri ve politikacılar federalizmi yeni hükümet sistemi olarak benimsemeyi kanaatindeydiler ve 2012'de Somali federalizmi benimseyerek daha önceden kurulmuş olan Puntland ve Somaliland eyaletlerine ek olarak dört eyalet kurdu. Bu eyaletler: Jubaland, Galmudug, Hirshabelle ve Güney Batı Eyaletleriydi. Bu makale, federalizmin Somali'de toplumsal kalkınmayı nasıl etkilediğine odaklanmakta ve federalizmin toplumsal kalkınma açısından meydana getirdiği fırsatları ve zorlukları değerlendirmektedir. Federalizm, ekonominin büyümesi, toplumsal güvenliği, eğitim ve sağlık sisteminin gelişimi, kadınların ve gençlerin toplumsal hayata daha çok katılması, güç dağılımının dengelenmesi ve siyasi istikrarın sağlanması gibi fırsatlar sunmuş olsa da bunların yanı sıra sınır çatışmaları, güç anlaşmazlıkları, doğal kaynakların sömürülmesi ve azınlık adaletsizlikleri gibi zorluklar da doğurmuş olmaktadır. Bu araştırma için kullanılan metodoloji anketlerden sağlanan verilerin analiz edilmesi şeklindedir

Silica-Supported Alginates From Djiboutian Seaweed as Biomass-Derived Materials for Efficient Adsorption of Ni(II)

International audienceThe development of environmentally friendly, reusable and highly performant adsorbent materials for the removal of heavymetal ions is a big challenge in the field of wastewater treatment. Therefore, in this study, ecofriendly composite materialsbased on alginates extracted from Sargassum sp (Alg.S) and Turbunaria (Alg.T) and supported on different silica parti-cles were prepared and used as adsorbents for Ni(II) ions removal from aqueous solutions. These composites efficientlyextract Ni(II) ions, i.e. the optimal adsorption amount of Ni 2+ reaches 251 mg.g−1 at pH 5 for one composite, surpassingthe adsorption capacities of other adsorbents reported so far in the literature. The kinetic data fit well with a pseudo-secondorder model. Furthermore, the adsorption in a binary system containing both Ni(II) and Pb(II) was also studied. The effectof pH, concentration, and other parameters on the adsorption capacity as well as on kinetics were systematically examined.These results demonstrate that ours composites show great potential as low-cost bio-adsorbents to remove Ni(II) ions fromaqueous solutions