Interface-induced magnetism in perovskite quantum wells

We investigate the angular dependence of the magnetoresistance of thin (< 1 nm), metallic SrTiO3 quantum wells epitaxially embedded in insulating, ferrimagnetic GdTiO3 and insulating, antiferromagnetic SmTiO3, respectively. The SrTiO3 quantum wells contain a high density of mobile electrons (~7x10^14 cm^-2). We show that the longitudinal and transverse magnetoresistance in the structures with GdTiO3 are consistent with anisotropic magnetoresistance, and thus indicative of induced ferromagnetism in the SrTiO3, rather than a nonequilibrium proximity effect. Comparison with the structures with antiferromagnetic SmTiO3 shows that the properties of thin SrTiO3 quantum wells can be tuned to obtain magnetic states that do not exist in the bulk material.Comment: Accepted for publication as a Rapid Communication in Physical Review

Fate mapping identifies the origin of SHF/AHF progenitors in the chick primitive streak

Heart development depends on the spatio-temporally regulated contribution of progenitor cells from the primary, secondary and anterior heart fields. Primary heart field (PHF) cells are first recruited to form a linear heart tube; later, they contribute to the inflow myocardium of the four-chambered heart. Subsequently cells from the secondary (SHF) and anterior heart fields (AHF) are added to the heart tube and contribute to both the inflow and outflow myocardium. In amniotes, progenitors of the linear heart tube have been mapped to the anterior-middle region of the early primitive streak. After ingression, these cells are located within bilateral heart fields in the lateral plate mesoderm. On the other hand SHF/AHF field progenitors are situated anterior to the linear heart tube, however, the origin and location of these progenitors prior to the development of the heart tube remains elusive. Thus, an unresolved question in the process of cardiac development is where SHF/AHF progenitors originate from during gastrulation and whether they come from a region in the primitive streak distinct from that which generates the PHF. To determine the origin and location of SHF/AHF progenitors we used vital dye injection and tissue grafting experiments to map the location and ingression site of outflow myocardium progenitors in early primitive streak stage chicken embryos. Cells giving rise to the AHF ingressed from a rostral region of the primitive streak, termed region ‘A’. During development these cells were located in the cranial paraxial mesoderm and in the pharyngeal mesoderm. Furthermore we identified region ‘B’, located posterior to ‘A’, which gave rise to progenitors that contributed to the primary heart tube and the outflow tract. Our studies identify two regions in the early primitive streak, one which generates cells of the AHF and a second from which cardiac progenitors of the PHF and SHF emerge.Esther Camp, Susanne Dietrich, Andrea Münsterber

How accurate are commercial-real-estate appraisals? evidence from 25 years of NCREIF sales data

In this study, we provide new evidence on the performance measurement and reporting of commercial real estate returns. We do so by examining the accuracy of commercial-real-estate appraisals that occurred prior to the sale of properties from the NCREIF National Property Index (“NPI”) during 1984 – 2010, a period which spans two up-and-down cycles of the market. We find that, on average, appraisals are more than 12% above, or below, subsequent sales prices that take place two quarters following the appraisal. Even in a portfolio context, allowing for offsetting positive and negative differences, appraisals are off by an average of 4% – 5 % of value, even after adjusting for capital appreciation during those two quarters. We also provide new evidence regarding how, and by how much, appraised values lag behind sales prices. We find that appraisals appear to lag the true sales prices, falling significantly below in hot markets and remaining significantly above in cold markets. This new evidence provides guidance to investors, regulators and others about how to interpret real-estate indices like the NPI that are based upon appraised values, in both a rising and falling market. Finally, we find that this “appraisal error” is largely systematic; we can explain more than half of the variation in the signed percentage difference in sales price and appraised value. Hence, appraisal errors are not due solely to property-specific heterogeneity.appraisal; commercial real estate; commingled real estate fund; NCREIF; real estate

Resistant barley varieties may facilitate control of Ramularia leaf spot

Ramularia leaf spot (RLS) is widely present in Denmark nowadays and has the potential to reach severity levels high enough to cause economic damage. The results of multi-location surveys and field trials of several years suggest that varietal resistance can be an efficient means for controlling RLS. The spring barley cultivars most affected by RLS possess mlo-resistance against powdery mildew while the least affected ones do not. Other mildew resistances as well as varietal susceptibility to other foliar diseases were not clearly related to the RLS reaction pattern of neither spring- nor winter barley cultivars. Promising RLS resistance donors may be the spring barleys Power, Helium, Isabella, Nathalie, Cruiser and Isotta and the winter barleys Lonni, followed by Chess, Lomerit, Nobilia, and Carola. However, more work is needed to develop reliable methods for efficient RLS resistance testing and to determine the nature and genetic basis of RLS resistance and its relation to varietal resistances against other diseases

Measuring Foregone Direct Benefits of Irrigation Water Transfers: The Effect of Model Specification

Crop Production/Industries, Resource /Energy Economics and Policy,

Does School Autonomy Make Sense Everywhere? Panel Estimates from PISA

Decentralization of decision-making is among the most intriguing recent school reforms, in part because countries went in opposite directions over the past decade and because prior evidence is inconclusive. We suggest that autonomy may be conducive to student achievement in well-developed systems but detrimental in low-performing systems. We construct a panel dataset from the four waves of international PISA tests spanning 2000-2009, comprising over one million students in 42 countries. Relying on panel estimation with country fixed effects, we identify the effect of school autonomy from within-country changes in the average share of schools with autonomy over key elements of school operations. Our results show that autonomy affects student achievement negatively in developing and low-performing countries, but positively in developed and high-performing countries. These results are unaffected by a wide variety of robustness and specification tests, providing confidence in the need for nuanced application of reform ideas.

Der Einfluss von Blütenduftstoffen auf die Oviposition der Rosskastanienminiermotte Cameraria ohridella

The larval stages of Cameraria ohridella develop mining in leaves of the horse chestnut tree Aesculus hippocastanum. The insect establishes three generations in Central Europe. During the appearance of the first generation the horse chestnut trees bloom. Further on, parallel to the flying time of all generations other plant species bloom. The olfactory detection of flower odour compounds and the influence on oviposition of C. ohridella were examined using trace analytical and electrophysiological methods as well as bioassays.Die Larven von Cameraria ohridella (Lepidoptera, Gracillariidae) entwickeln sich als Minierer in den Blättern der gemeinen Rosskastanie, Aesculus hippocastanum. In Mitteleuropa können drei Faltergenerationen ausgebildet werden, wobei die erste während der Blütezeit der Wirtspflanze A. hippocastanum fliegt. Der Schmetterlingsstrauch Buddleja davidii blüht von Sommer bis Herbst während der Flugzeit der zweiten und dritten Generation. Die großen Blütenstände locken zahlreiche Insekten an, die den Nektar als Nahrung nutzen. Mit Hilfe von Spurenanalytischen und elektrophysiologischen Methoden (GC-MS, EAG) sowie Verhaltensversuchen wurde der Einfluss von Blütendüften auf die Oviposition der Rosskastanienminiermotte untersucht. Der Blütenduft von A. hippocastanum und B. davidii unterschied sich in der Komposition emittierter Komponenten. C. ohridella war in der Lage, Blütendüfte zu detektieren. Die untersuchten Blütenduftstoffkomponenten beeinflussten die Oviposition der Miniermotten. Benzaldehyd, Linalool und (E)-&#946;-Caryophyllen wurden von Rosskastanienblüten emittiert und steigerten die Oviposition auf den Blättern. Benzylalkohol wurde nicht von der Rosskastanie abgegeben und reduzierte im Gegensatz zu den anderen Duftstoffkomponenten die Eiablage. Der Blütenduft der Rosskastanie kann Faltern der ersten Generation bei der Wirtspflanzensuche helfen. In Zweifachwahltests mit getopften Rosskastaniensämlingen und blühendem Sommerflieder wurden die Blätter der Wirtspflanze bei der Eiablage bevorzugt. Aber auch auf den Blättern des Sommerflieders konnten abgelegte Eier gezählt werden. Bei alleinigem Angebot (Einfachwahltest) stieg die Anzahl der abgelegten Eier auf dem blühenden Sommerflieder. Falter der dritten Generation, die im Herbst auf eine starke Blattverbräunung der Wirtspflanze A. hippocastanum durch Minierfraß treffen und dort keine grünen Blattbereiche mehr finden, suchen auf anderen Wirtspflanzen einen geeigneten Eiablageplatz. Dabei können Blütenduftstoffkomponenten die Oviposition der Motten beeinflussen