A Model of the Irish Housing Sector

This paper presents a model of the Irish housing sector which has been created to nest within the Irish block of the ESCB multi-country model which is maintained in the Economic Analysis Research and Publications Department. The model consists of a demand and supply side and results from it are used to examine for the presence of a bubble in the Irish housing market.

Alternative Models of the Irish Supply Side

This paper is a product of the ongoing re-estimation of the Irish macro model. This is part of the EMI Multicountry Model. The paper is concerned with the estimation of a system of equations, which seek to capture the salient features of the supply-side of the Irish economy. Expressions are required for the marginal cost of production, long-run labour and capital demand. The estimated parameters from the system are then used to simulate the underlying production function thereby permitting the generation of key macroeconomic indicators such as the output gap and total factor productivity. A Cobb-Douglas approach is used initially to approximate the underlying technology within the economy. The associated factor demands with the Cobb-Douglas are easily derived and the functional form has the advantage of relative computational ease. Initial results from this approach yield very large measures of the output gap. Therefore, these results are then compared with the use of more flexible functional forms as a control or check. In particular, a translog production function approach is adopted and the consequent output gap is calculated. This output gap is then used as a benchmark for comparison. As a result, the Cobb-Douglas approach is re-visited and adjustments are made to the initial specification. The structural change witnessed by the Irish economy throughout the 1990’s is proxied for by the use of a number of different methods. It is found that by adopting a non-linear improvement in technology through time, the output gap achieved with the Cobb-Douglas approach correlates quite strongly with that from the more flexible translog form. This approach is then advocated for the macro model.

Dynamic Factor Demands in a Changing Economy: An Irish Application

In this paper, more advanced models of the Irish supply side are examined and applied. In particular, a specification of a flexible and dynamic model, which nests more traditional approaches, is adopted. The approach consists of a two-stage process. Firstly, a static translog cost function for the entire economy is specified and associated factor demands are estimated. Then a more flexible dynamic specification is presented which has as a special case the initial static specification. Standard Likelihood Ratio tests can examine the validity of the restrictions underpinning the relatively standard static specification. Estimating a dynamic flexible functional form specification of the supply side has a number of advantages over more traditional approaches such as the Cobb-Douglas. The elasticity of substitution between the factor inputs labour and capital can be determined by the data and not imposed by the researcher. Also the standard static approach to supply-side analysis assumes that producers respond instantaneously in their factor input decisions vis-à-vis changes in factor input prices. This assumption is rather unrealistic particularly given the nature of capital usage and investment. Also the differences in long and short run elasticities for factor demands are examined. The relationship between the two sets of elasticities in formalised in the Le Chatelier principle. The use of the more dynamic and flexible specification is justified in an Irish case. Input use adjustment is found to occur on a multi-period basis and not in the instantaneous fashion assumed by a static approach. The Le Chatelier principle is also observed meaning that long-run price elasticities of factor demands in absolute terms are greater than the short-run equivalents.

Efficacy of entomopathogenic nematodes for control of large pine weevil, Hylobius abietis: effects of soil type, pest density and spatial distribution

The large pine weevil Hylobius abietis (L.), LPW, is a major pest of trees in replanted coniferous forests in northern Europe. The use of entomopathogenic nematodes (EPNs) applied against developing stages for population suppression is increasingly recognized as an effective alternative to plant protection using chemical pesticides. Here, we report results from a series of trials we conducted over 2 years using two species of EPN, Steinernema carpocapsae (Weiser) and Heterorhabitis downesi (Stock, Griffin, and Burnell) with different foraging strategies. Trials were conducted at lodgepole pine sites in Ireland on both mineral and peat soil type. EPN suspension was applied to the stumps of felled pine trees, and EPN efficacy was determined afterwards by directly assessing parasitism rates after debarking one quarter of the stumps and by collecting emerging adult weevils from traps erected over other treated and control stumps. Our results suggest that both species of EPN are equally effective in suppressing LPW populations to below the current, informal thresholds of economic damage. EPN were equally efficient in controlling LPW in peat and in mineral (lithosols/regosols and acid brown earth/brown podzolics) soils. Weevil density and distribution within pine stumps in peat versus mineral sites can explain patterns of LPW parasitism and suppression. Our results also suggest that infestation level (number of weevils per stump) can be an important factor in forecasting EPN application success as there is evidence of negative density-dependent parasitism when weevil densities were high. © 2016 Springer-Verlag Berlin Heidelber

Improved crush energy absorption in 3D woven composites by pick density modification

Although 3D woven composites have exceptional out-of-plane properties, there is a lack of understanding for these materials in crash application in automotive and aerospace industries. To encourage the use of 3D wovens in crashworthy automotive structures, knowledge must be gained so that designers can adjust the highly flexible weave parameters to create tailor-made performance materials. Here we show that fabric pick density causes large changes in progressive failure modes and associated energy absorption, particularly in the dynamic regime, where the quasi-static to dynamic energy absorption loss typical of composites is completely removed. Compression and flexure properties, which are known to be linked to crash performance in composites, are also investigated for these 3D woven layer-to-layer interlock carbon-epoxy composite structures. 3D fabric preforms are manufactured in three different pick densities: 4, 10 & 16 wefts/cm. With a constant warp density of 12 warps/cm from carbon fibres. Increasing the pick density improved specific energy absorption (SEA) even in relatively inefficient progressive failure modes like folding, which has not previously observed in composite materials. SEA values up to 104 J/g (quasi-static) and 93 J/g (dynamic) are recorded. This work shows that minor weft direction (transverse) weave changes can lead to sizeable improvements in warp direction (axial) energy absorption without fundamentally redesigning the weave architecture

Chronic Lymphocytic Leukemia: Insights from Lymph Nodes & Bone Marrow and Clinical Perspectives

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by highly variable distribution of tumor mass between peripheral blood, bone marrow and lymphoid organs which is important for staging, classification and prognosis. These clinical findings with novel data about importance of B-cell receptor and its stimulation with the support of microenvironment indicate important role of tissues (lymphoid organs and bone marrow) in the pathogenesis of B-CLL. Here is presented the novel approach of simultaneous characterization of B-CLL cells form peripheral blood, bone marrow and lymph nodes by flow cytometry and immunocytochemistry, defining inter- and intraclonal diversity with respect to various molecules. These include adhesion molecules (integrins, immunoglobulins, selectins), chemokine receptors (including CXCR-4), signaling molecules and prognostic factors (CD38 and ZAP-70), proliferation and apoptosis markers (including Ki67, AgNORs with PK index, survivin, bcl-2) and therapeutic targets (CD20 and CD52) and residual hematopoietic stem cells. A number of interesting significant interactions have been discovered, pointing to the important role of neoplastic cell microenvironment. These may in addition to insights in pathogenesis and roles of different microenvironments add to diagnosis, prognosis and treatment of B-CLL patients