The impact of changing agricultural policies on Libyan agricultural performance

Before the discovery of oil, the Libyan economy was characterized by its dependence on the agricultural sector. Oil was discovered in Libya in the late nineteen-fifties. High oil revenues provided an appropriate environment for the financing of all development projects, including agricultural projects. Although the agricultural sector in Libya has the financial and natural potential to make the agricultural sector more effective, it is confronted by many challenges that prevent its effective development. The Libyan government in the nineteenseventies and the nineteen-eighties formulated policies for agricultural development through a set of medium-term plans (Three-year Plan 1973-1975, Five-year Plan 1976/1980 and Five-year Plan 1981-1986). However, by the middle of the nineteen-eighties there was a change in the mechanism of these programmes and plans, to a series of annual policies. The main aim of this study was to investigate the impact of changing agricultural policy approaches on Libyan agricultural performance. A mixed methods approach was adopted that rested on the triangulation of data from stakeholders (farmers and agricultural policy-makers) and policy documents relating to the performance of the Libyan agricultural sector. The findings indicated that the performance of the agricultural sector in the period of medium term plans, achieved higher contributions to the GDP. The performance of the agricultural sector declined when policies were developed on an annual basis and the government withdrew its subsidies for the sector. The distinguishing feature of the two approaches to agricultural policies in Libya is their diverse impact on the performance of the agricultural sector. In addition, the decline of oil prices in the eighties was the main reason behind the change in approach to policy. The main contributory value of this research is that it provides for the first time an in-depth understanding of how changing policies impact on the performance of the agricultural sector in Libya. It does this by drawing attention to the consideration of the impact of policy changes on agricultural sector development. The research generates findings that are transferable to other developing countries especially those in northern Africa with economies similar to that of Libya; it also provides an opportunity for further research into other internal and external factors that impact on policy and agricultural development, especially in oil producing countries in Africa

Prognostic value of estimated glomerular filtration rate in hospitalised older patients (over 65) with COVID-19: a multicentre, European, observational cohort study

Background: The reduced renal function has prognostic significance in COVID-19 and it has been linked to mortality in the general population. Reduced renal function is prevalent in older age and thus we set out to better understand its effect on mortality. Methods: Patient clinical and demographic data was taken from the COVID-19 in Older People (COPE) study during two periods (February–June 2020 and October 2020–March 2021, respectively). Kidney function on admission was measured using estimated glomerular filtration rate (eGFR). The primary outcomes were time to mortality and 28-day mortality. Secondary outcome was length of hospital stay. Data were analysed with multilevel Cox proportional hazards regression, and multilevel logistic regression and adjusted for individual patient clinical and demographic characteristics. Results: One thousand eight hundred two patients (55.0% male; median [IQR] 80 [73–86] years) were included in the study. 28-day mortality was 42.3% (n = 742). 48% (n = 801) had evidence of renal impairment on admission. Using a time-to-event analysis, reduced renal function was associated with increased in-hospital mortality (compared to eGFR ≥ 60 [Stage 1&2]): eGFR 45–59 [Stage 3a] aHR = 1.26 (95%CI 1.02–1.55); eGFR 30–44 [Stage 3b] aHR = 1.41 (95%CI 1.14–1.73); eGFR 1–29 [Stage 4&5] aHR = 1.42 (95%CI 1.13–1.80). In the co-primary outcome of 28-day mortality, mortality was associated with: Stage 3a adjusted odds ratio (aOR) = 1.18 (95%CI 0.88–1.58), Stage 3b aOR = 1.40 (95%CI 1.03–1.89); and Stage 4&5 aOR = 1.65 (95%CI 1.16–2.35). Conclusion: eGFR on admission is a good independent predictor of mortality in hospitalised older patients with COVID-19 population. We found evidence of a dose-response between reduced renal function and increased mortality

An investigation of the effectiveness of multimedia characteristics on CAD learning performance

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

On the relation between Ni4Ti3-precipitation in Ni-rich NiTi shape memory alloys (during aging and creep) and martensitic transformations

The influence of aging and creep on the martensitic transformation of a Ti-50.7 at.%Ni shape memory alloy was investigated. The particle precipitation which occurs during aging of the solution annealed and water quenched material at 500°C is strongly affected by the presence of small external stresses (pre-loads). Stress free aging results in local precipitation near grain boundaries while aging under a small pre-load (2 MPa) results in a homogeneous precipitation of particles. The corresponding microstructures are associated with specific types of DSC charts. As compared to the solution annealed material, the material after 11 hours of creep (530°C, 120 MPa) and after stress free aging for 11 hours at 530°C exhibit an 18°C increase in phase transition temperatures. The accumulated creep strain influences the shape, spatial distribution and volume fraction of Ni$_4$Ti$_3$ precipitates; it does not strongly affect the transformation behavior. This experimental result is discussed in terms of the counteracting effects of Ni-depletion due to the precipitation of Ni$_4$Ti$_3$ particles and the formation of a dislocation substructure. Dynamic precipitation moreover has an effect on the shape of creep curves, which exhibit sharp creep rate minima at small creep strains

Effects of multimedia characteristics on novice CAD learners practice performance

Based on the assumption that providing information using multiple modalities improves learners' performance, the teaching of computer-aided design (CAD) in the built environment is increasingly shifting from printed material to a multimedia approach. Yet, the evidence base suggests that presenting information by using multiple modalities does not always enhance learning. This paper reports on an empirically based study that sought to determine under which conditions architectural engineering students benefit most from multimedia CAD learning. It investigated the effects of multimedia on novice CAD learners' practice performance (time and accuracy). One hundred and one students were randomly assigned to four groups to undertake specific CAD learning tasks, with different treatments; media mode (printed-text vs. audio) and the visual mode (static-illustration vs. animation). The results indicated that the audio mode shortened learning time much more than the text mode. Conversely, the text mode enhanced CAD design accuracy, in comparison with the audio mode with the illustration mode alone. In addition, the animation mode improved design accuracy with text and audio significantly more than with illustration visual mode. The animation mode increased the learning time considerably with the text mode. The implications of the design of CAD instructional materials for architectural engineering education are examined. © 2012 Copyright Taylor and Francis Group, LLC

Influence of precipitation and dislocation substructure on phase transformation temperatures in a Ni-rich NiTi-shape memory alloy

The present work studies the influence of different thermo mechanical treatments on phase transformation and creep of a Ti-50.7at%Ni shape memory alloy. Thermo-mechanically processed, solution annealed, tempered and pre-crept material states show different phase transformation behaviour. Precipitation of Ti3Ni4 particles can rationalize a 20°C increase in phase transition temperatures. Changes of dislocation density and subgrain size also have a systematic but small effect on the martensitic transformation. There is a strong influence of small preloads on the shape of individual creep curves in the early stages of creep which is associated with the precipitation of Ti3Ni4