A decomposition analysis of the emission of CO2

In 1997 many countries, including the Netherlands, signed the Kyoto treaty. According to this protocol, the emission of CO2 in the Netherlands in the years 2008-2012 should be on average 6% below the level of 1990. However, the emission still shows an increasing pattern. Part of the increase may be compensated by supporting projects abroad, hence the goals may still be reached if domestic emission does not increase too far. All in all, it is not sure whether the Netherlands will meet the goals of this protocol. Several factors contribute to changes in the emission of CO2. The figures of CO2 emission only show the net effect. In order to see whether technological changes decreases the emission of CO2 and whether the increase in CO2 is mainly due to economic growth, this paper uses a decomposition analysis to compute the effect of these factors. In order not to complicate the analysis too much, it was decided to focus on the emissions of CO2 and ignore the other greenhouse gasses. The emission of CO2 is the most important issue, because CO2 is the most important greenhouse gas and because the emission of the other greenhouse gasses is decreasing whereas the emission of CO2 is increasing. Policy is therefore likely to be most effective if it focuses on CO2. Further, the decomposition method can only be used to analyse the emission of producers. Emission by consumers is therefore ignored.

Do Exchange Rates Move in Line With Uncovered Interest Parity?

According to uncovered interest rate Parity (UIP), the expected relative change in an exchange rate is equal to the difference between interest rates between the two currencies. Empirically, UIP is frequently rejected. In this paper, we examine whether exchange rates have at least any tendency to move in the direction predicted by UIP and whether exchange rates tend to move more in line with UIP in periods with large interest rate differentials.Exchange rates;Uncovered interest rate parity;Logit models

Spiral order by disorder and lattice nematic order in a frustrated Heisenberg antiferromagnet on the honeycomb lattice

Motivated by recent experiments on Bi$_3$Mn$_4$O$_{12}$(NO$_3$), we study a frustrated $J_1$-$J_2$ Heisenberg model on the two dimensional (2D) honeycomb lattice. The classical $J_1$-$J_2$ Heisenberg model on the two dimensional (2D) honeycomb lattice has N\'eel order for $J_2 J_1/6$, it exhibits a one-parameter family of degenerate incommensurate spin spiral ground states where the spiral wave vector can point in any direction. Spin wave fluctuations at leading order lift this accidental degeneracy in favor of specific wave vectors, leading to spiral order by disorder. For spin $S=1/2$, quantum fluctuations are, however, likely to be strong enough to melt the spiral order parameter over a wide range of $J_2/J_1$. Over a part of this range, we argue that the resulting state is a valence bond solid (VBS) with staggered dimer order - this VBS is a nematic which breaks lattice rotational symmetry. Our arguments are supported by comparing the spin wave energy with the energy of the dimer solid obtained using a bond operator formalism. Turning to the effect of thermal fluctuations on the spiral ordered state, any nonzero temperature destroys the magnetic order, but the discrete rotational symmetry of the lattice remains broken resulting in a thermal analogue of the nematic VBS. We present arguments, supported by classical Monte Carlo simulations, that this nematic transforms into the high temperature symmetric paramagnet via a thermal phase transition which is in the universality class of the classical 3-state Potts (clock) model in 2D. We discuss the possible relevance of our results for honeycomb magnets, such as Bi$_3$M$_4$O$_{12}$(NO$_3$) (with M=Mn,V,Cr), and bilayer triangular lattice magnets.Comment: Slightly revise

The macrobenthic fauna in the Dutch sector of the North Sea in 2002 and a comparison with previous data

In this report the results are presented of a macrobenthos survey on the Dutch Continental Shelf (DCS), carried out in spring 2001. The survey forms part of the 'Biological monitoring programme of marine waters' (MON*BIOLOGIE, generally referred to as 'BIOMON') which was initiated by the National Institute for Coastal and Marine Management (RIKZ). The purpose of the programme is to obtain insight into the year-to-year variations of the macrobenthic assemblages and to detect trend-like changes, that possibly indicate anthropogenic influences on the marine environment (e.g. eutrophication, pollution, beam-trawl fishery). Within the framework of this project fieldwork is carried out every year in spring. In 2001 the 100 BIOMON stations were sampled in the period between February 27 and April 4. On the basis of the results collected in 2001 and previous years an analysis is made of the trends and fluctuations of some selected species and of basic community attributes over the period 1986-2001. The community attributes studied were the diversity, abundance and biomass of the total macrofauna and of the 4 major taxonomic groups. Temporal variation or trends were investigated separately for each of the four subareas in the DCS i.e. the Coastal, Offshore areas, Dogger Bank and Oyster Ground.The conclusions of this study can be summarized as follows:1. The sediment composition in the four subareas was quite similar to that found in previous years. Also at most of the individual stations the median grain size and silt content of the sediment had hardly changed. There were only three stations with strong year to year differences in sediment composition. At the stations OFF 2 and OFF 6 the median grain size strongly fluctuated and at station OYS 8 the silt content. lt is suggested that these stations are situated at a sharp local gradient.2. At the community level, there were only a few slight changes compared to preceding years. In the offshore area and in the coastal area there seemed to be a tendency for increased diversity. This was not due to increased species richness but to a more even distribution in the abundance of the various species. With respect to the share of the different taxonomic groups to the total biomass, a decrease has been observed in previous years in molluscs, particularly at the Dogger Bank and in the Oyster Ground. This decrease has come to an end in 2001 and turned into an increase. Since molluscs also increased numerically, the increase in biomass is caused by higher densities rather than by a larger size of the animals.3. At the Dogger Bank a few species showed a remarkable decrease. The polychaete <i>Nephtys cirrosa</i> shows a decrease from 2000 onwards, the sand star <i>Acrocnida brachiata</i> and the bivalve <i>Mysella bidentata</i> from 1999 and the polychaete <i>Aricidea minuta</i> decreased in 1997 and has no longer been found since 1999. On the other hand the population density of the gastropod <i>Euspira nitida</i> (formerly called <i>Natica alderi</i>) had recovered from a dip in the period 1998-2000. The occurrence of <i>Ensis phaxoides</i> is new for the Dogger Bank. Further, living specimens of the bivalve <i>Gouldia minima</i> and the gastropod <i>Turbonilla pusilla</i> have not been found on the DCS before.4. In the Oyster Ground the decreasing trend that has been observed in previous years in the brittle star <i>Amphiura filiformis</i> and the polychaete <i>Nephtys hombergii</i> had turned into au increase in 2001. However, densities of <i>A. filiformis</i> were still low at the Frisian Front. There was a number of species that have not been found before during the BIOMON programma. The occurrence of the polychaete <i>Nephtys assimilis</i> is new for the Oyster Ground. The records of the polychaete <i>Sabella penicillus</i>, the bivalves <i>Montacuta tenella</i> and <i>Gari costulata</i> and the gastropods <i>Turbonilla pusilla</i> and <i>Roxania utriculus</i> are probably new to the DCS.5. In the offshore area, a slightly increasing trend that has been observed in the sea urchin <i>Echinocardium cordatum</i> in the preceding years has come to an end in 2001. In contrast, the gastropod <i>Euspira nitida</i> showed a recovery of populations from 2000 onwards. Station OFF 33 that in 2000 had shown a rich fauna that was clearly different from the other stations in the offshore area was still rich in 2001, but the fauna composition did not show 'exotic' elements.6. In the Coastal area there seemed to be a recovery of the populations of the gastropod <i>Euspira nitida</i>. After an 8 year period of very low densities the species returned at 5 stations, albeit in low numbers. The bivalve <i>Tellina fabula</i> also showed a steady increase, after a dip in the second half of the nineties. At stations where banks of <i>Spisula subtruncata</i> or <i>Ensis americanus</i> occurred, biomass values were very high

Monitoring the invertebrate benthic fauna in the Dutch sector of the North Sea 1991 - 2005: an overview

In the framework of ‘BIOMON’, a national program for biological monitoring of marine waters, the invertebrate benthic fauna of the Dutch Continental Shelf (DCS) has been monitored from 1991 onwards. The monitoring is based on a boxcore sampling program yearly carried out in spring at 100 stations on the DCS. The aim is to generate a time series that can form a basis to detect possible trends in the development of thefauna in different areas within the DCS. From the very beginnng it became clear that in the fauna of the DCS four clusters could be discerned that are geographically well defined: the Dogger Bank, the Oyster Ground, the southern offshore area and the coastal area. At the community level there were no trendwise changes over the period of monitoring. Species diversity was consistently highest at the Dogger Bank and in the Oyster Ground, on average twice as high as in the southern offshore and coastal areas. Faunal densities were generally the highest in the Oyster Ground. The highest biomass values were found in the coastal area, due to the presence of banks of bivalves (<i>Spisula subtruncata</i> and <i>Ensis americanus</i>). At the species level a few trends were observed: the disappearance of the polychaete <i>Aricidea minuta</i> from the DCS around 2000 and a dip in the densities of the brittle star <i>Amphiura filiformis</i> in the Oyster Ground during the second half of the nineties. A rather strong decrease of silt contents of the sediment in the latter area after 2001 was not reflected in a change in the abundance of one or more common species. A comparison of the monitoring data with data collected in the period 1975 – 1981 appeared to be possible for only a few (mainly mollusc) species in the Oyster Ground, but indicated that the gastropod <i>Turritella communis</i> has strongly decreased since those years whereas there was a significant increase in the abundance of several small bivalve species

Dental Practitioners' Attitudes, Subjective Norms and Intentions to Practice Atraumatic Restorative Treatment (ART) in Tanzania.

The aim of this study was to describe the attitude and subjective norm of dental practitioners towards practicing the atraumatic restorative treatment (ART) in Tanzania. A pre-tested questionnaire on attitudes and subjective norms to practice ART was mailed to all 147 dental practitioners working in the regional and district government clinics. The independent variables were: gender, working experience, qualification and ever heard of ART. The dependent variables were: attitude, subjective norm and intention to practice ART. Chi-square tests and multiple regression analysis were used to test for effects between independent and dependent variables. Significance level was set at 5%. A total of 138 practitioners returned completed questionnaires. More experienced dental practitioners encountered moderate social pressure than less experienced dental practitioners, who met strong social pressure (p=0.045). A total of 73.2% of dental practitioners felt that ART was worth introducing in Tanzania, 92.8% recommended ART training for all dental practitioners and 97.8% recommended inclusion of ART in dental curricula. Positive attitude, strong subjective norm and high intention to practice ART were recorded in 76.3%, 28.1% and 90.6% of the practitioners, respectively. Only subjective norm had a statistically significant influence on the intention to practice ART (p<0.0001). The results indicated that dental practitioners were willing to have ART introduced in Tanzania and had positive attitudes towards practicing this technique. Nevertheless, their intention to perform ART was strongly influenced by social pressures. Therefore, in order to have a successful introduction of ART in Tanzania, people who matter in the daily practice of dental practitioners need to accept and appraise the ART approach positively

NGC 3310, a galaxy merger?

The HI structure and kinematics of the peculiar starburst galaxy NGC 3310 (Arp 217, UGC 5786) are discussed. New evidence bearing on the origin of the starburst is presented. The bulk of HI coincides with the bright optical disk and shows differential rotation. Its velocity dispersion is, however, unusually large for a spiral galaxy (up to 40 km/s), suggesting that the disk is highly perturbed as already indicated by optical emission line spectroscopy. There are, in addition, two prominent HI tails, one extending to the north-west and the other, somewhat patchy, to the south. These HI tails, the perturbed kinematics and the peculiar optical morphology strongly suggest a recent merger between two gas-rich galaxies. This seems to have been a major merger in which most of the gas in the inner parts has been preserved in neutral atomic form and either one of the progenitor disks has survived or a new disk has formed.Comment: 10 pages, 11 figures, accepted for publication in A&

Longitudinal flow evolution and turbulence structure of dynamically similar, sustained, saline density and turbidity currents

Experimental results are presented concerning flow evolution and turbulence structure of sustained saline and turbidity flows generated on 0°, 3°, 6°, and 9° sloping ramps that terminate abruptly onto a horizontal floor. Two-component velocity and current density were measured with an ultrasonic Doppler velocity profiler and siphon sampler on the slope, just beyond the slope break and downstream on the horizontal floor. Three main factors influence longitudinal flow evolution and turbulence structure: sediment transport and sedimentation, slope angle, and the presence of a slope break. These controls interact differently depending on flow type. Sediment transport is accompanied by an inertial fluid reaction that enhances Reynolds stresses in turbidity flows. Thus turbidity flows mix more vigorously than equivalent saline density flows. For saline flows, turbulent kinetic energy is dependent on slope, and rapid deceleration occurs on the horizontal floor. For turbidity flows, normalized turbulent kinetic energy increases downstream, and mean streamwise deceleration is reduced compared with saline flows. The slope break causes mean bed-normal velocity of turbidity flows to become negative and have a gentler gradient compared with other locations. A reduction of peak Reynolds normal stress in the bed-normal direction is accompanied by an increase in turbulent accelerations across the rest of the flow thickness. Thus the presence of particles acts to increase Reynolds normal stresses independently of gradients of mean velocity, and sediment transport increases across the break in slope. The experiments illustrate that saline density currents may not be good dynamic analogues for natural turbidity currents

The matrix-F prior for estimating and testing covariance matrices

The matrix-F distribution is presented as prior for covariance matrices as an alternative to the conjugate inverted Wishart distribution. A special case of the univariate F distribution for a variance parameter is equivalent to a half-t distribution for a standard deviation, which is becoming increasingly popular in the Bayesian literature. The matrix-F distribution can be conveniently modeled as a Wishart mixture of Wishart or inverse Wishart distributions, which allows straightforward implementation in a Gibbs sampler. By mixing the covariance matrix of a multivariate normal distribution with a matrix-F distribution, a multivariate horseshoe type prior is obtained which is useful for modeling sparse signals. Furthermore, it is shown that the intrinsic prior for testing covariance matrices in non-hierarchical models has a matrix-F distribution. This intrinsic prior is also useful for testing inequality constrained hypotheses on variances. Finally through simulation it is shown that the matrix-variate F distribution has good frequentist properties as prior for the random effects covariance matrix in generalized linear mixed models