Development and application of a sensitive, high precision weighing lysimeter for use in greenhouses

A high precision weighing lysimeter for measuring evapotranspiration in greenhouses was developed. The instrument has a measurement of sensitivity of one part in 106, that is one order of magnitude better than any other so far described in the literature. With it, evaporation rates in a greenhouse, even at night, can be measured on a one minute time scale. Development and construction of the instrument are described and measurements of the transpiration of a tomato crop in a greenhouse are used to demonstrate its capabilities

Quantitative estimation of plant characteristics using spectral measurement: A survey of the literature

There are no author-identified significant results in this report

The Investment Casualties of War: Global Impacts of Armed Conflict on Foreign Direct Investment Inflows

Abstract: Involvement in the outbreak of an armed conflict can present a variety of potential risks to an involved nation’s economy. In this paper I examine if one one of those risks, specifically that a new war could scare away foreign investment actually occurs and whether the intensity of the conflict increases or lessens the potential impact. Using ordinary least squares on panel data from 1966 to 2015, I examine the short and long term impacts of armed conflict on global foreign direct investment (FDI) inflows using two measures of conflict intensity: Large conflicts or ‘wars’, with 1000 or more battle-related deaths and small conflicts, between 25-999 battle related deaths in a given year. Throughout the sample, I find that large conflicts are associated with a strong and negative relationship with FDI inflows associated with a conflict’s onset and end. First, I find a consistent and large negative impact on FDI inflows into an involved country associated with the outbreak of a new large conflict in the year after a conflict’s start. Additionally, once a large conflict does end, it takes approximately 3 years before FDI inflow levels return to positive levels. In order to asses long term impacts on FDI inflows, I test a third model examining conflict frequency by country, using the total number of conflicts that occur in 1, 5, 10, and 25 year periods. Surprisingly, the total amount of conflicts that occur in a country over time regardless of intensity does not seem to hold a statistically significant impact on FDI inflows, reflecting what is likely a rather short term impact of armed conflict on the investment decisions of foreign firms and investors

Engaging communities, experiential learning and a classroom in the real world

Conference Theme: New Approaches in Teaching and Learning at Tertiary LevelAs part of curriculum reform at The University of Hong Kong, one of the key aspects is the implementation of experiential learning. By taking students out of the classroom into the real world, the traditional construct of problem-based learning, in which each problem proceeds an expected answer, is reversed. Introducing students in undergraduate education to complex situations with uncertain outcomes leads to a shift in educational priorities, a deeper understanding of the nature of inquiry, and the attainment of a wide variety of tools for knowledge acquisition. This paper presents three distinct courses in the Faculty of Architecture, each of which implemented a different aspect of experiential learning. The first course introduced students to an urgent contemporary issue in the local community and allowed them to actively provoke positive change through design research and community engagement. In the second course, students participated in the design and physical renovation of a 300-year old bridge in China. The third course was a multi-disciplinary design studio based upon the rebuilding of a traditional Chinese village. All three courses engaged students in novel situations with ill-defined problems and allowed them to confront the complexities involved in the application of theoretical ideas to make actual impact in the real world. This paper presents the approach and methodologies of the three courses’ in their collaboration with local communities’ to raise their awareness, enable their participation, and improve their lives. It concludes with a reflection on the challenges of achieving and assessing the stated learning outcomes and several lessons for future iterations of this type of curricular approach.postprin

Strain-induced kinetics of intergrain defects as the mechanism of slow dynamics in the nonlinear resonant response of humid sandstone bars

A closed-form description is proposed to explain nonlinear and slow dynamics effects exhibited by sandstone bars in longitudinal resonance experiments. Along with the fast subsystem of longitudinal nonlinear displacements we examine the strain-dependent slow subsystem of broken intergrain and interlamina cohesive bonds. We show that even the simplest but phenomenologically correct modelling of their mutual feedback elucidates the main experimental findings typical for forced longitudinal oscillations of sandstone bars, namely, (i) hysteretic behavior of a resonance curve on both its up- and down-slopes, (ii) linear softening of resonant frequency with increase of driving level, and (iii) gradual recovery (increase) of resonant frequency at low dynamical strains after the sample was conditioned by high strains. In order to reproduce the highly nonlinear elastic features of sandstone grained structure a realistic non-perturbative form of strain potential energy was adopted. In our theory slow dynamics associated with the experimentally observed memory of peak strain history is attributed to strain-induced kinetic changes in concentration of ruptured inter-grain and inter-lamina cohesive bonds causing a net hysteretic effect on the elastic Young's modulus. Finally, we explain how enhancement of hysteretic phenomena originates from an increase in equilibrium concentration of ruptured cohesive bonds that are due to water saturation.Comment: 5 pages, 3 figure

Predicting Recurrent Venous Thromboembolism in Patients With Deep-Vein Thrombosis: Development and Internal Validation of a Potential New Prediction Model (Continu-8).

Background: Previous prediction models for recurrent thromboembolism (VTE) are often complicated to apply and have not been implemented widely. Aim: To develop and internally validate a potential new prediction model for recurrent VTE that can be used without stopping anticoagulant treatment for D-dimer measurements in patients with provoked and unprovoked DVT. Methods: Cohort data of 479 patients treated in a clinical care pathway at Maastricht University Medical Center were used. Predictors for the Cox proportional hazards model (unprovoked DVT, male gender, factor VIII levels) were derived from literature and using forward selection procedure. The scoring rule was internally validated using bootstrapping techniques and the predictive ability was compared to existing prediction models. Results: Patients were followed for a median of 3.12 years after stopping anticoagulation treatment (IQR 0.78, 3.90). Sixty-four of 479 patients developed recurrent VTE (13%). The scoring rule consisted of unprovoked DVT (yes: 2 points), male sex (yes: 1 point), and factor VIII > 213 % (yes: 2 points) and was categorized into three groups [i.e., low risk (score 0), medium risk (scores 1, 2, or 3) and high risk (scores 4 and 5)]. The concordance statistic was 0.68 (95% CI: 0.61, 0.75). Conclusion: The discriminative ability of the new Continu-8 score was adequate. Future studies shall verify this score in an independent setting without stopping anticoagulation treatment