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Overlapping and specific patterns of GDNF, c-ret and GFRα mRNA expression in the developing chicken retina

GDNF and the GDNF receptors, c-Ret, GFRα1 and 2 mRNA is expressed in the developing chicken retina. GDNF labelling was mainly found in embryonic day 4-5 retina but weak labelling could also be found over scattered retinal cells at later stages. c-ret labelling was found over ganglion cells, amacrine and horizontal cells; the preferred GDNF receptor (GFRα1) over amacrine and horizontal cells; and t

Volcanic influence on centennial to millennial Holocene Greenland temperature change

Solar variability has been hypothesized to be a major driver of North Atlantic millennial-scale climate variations through the Holocene along with orbitally induced insolation change. However, another important climate driver, volcanic forcing has generally been underestimated prior to the past 2,500 years partly owing to the lack of proper proxy temperature records. Here, we reconstruct seasonall

Lag truncation and the local asymptotic distribution of the ADF test for a unit root

The issue of lag selection in ADF unit root testing is important, even asymptotically, for if the number of lags is not allowed to increase at a certain rate the test might not be correctly sized. However, size control is not the only concern. Indeed, simulations have repeatedly shown how increasing lag lengths tend to be associated with reductions in power, thus adding to the well-known low power

Ökad tillgänglighet med följsam logistik

Logistik är ett ämnesområde som får allt större betydelse i allt fler branscher. Logistik sägs ha initierats av Napoleon då han utförde militära insatser på 1800-talet. För att klara matförsörjningen för sina militärer och för att underhålla den utrustning som fördes med trupperna så var han tvungen att ta med smeder, kockar och andra hantverkare som kunde försörja trupperna med mat och återställa

'This Is The Hell That I Have Heard Of' : Some Dialectical Images in Fossil Fuel Fiction

How can the realities of global warming be made visible in literary texts? After the rise of 'cli-fi', it might be time to return to a trove of literature written long before the discoveries of climate science: fiction about fossil fuels. It is filled with premonitions of disasters, such as extreme heat and terrible storms. Focusing on two texts - Ghassan Kanafani's Men in the Sun and Joseph Conra

Analysis of slab heating characteristics in a reheating furnace

For a reheating furnace, an analysis of thermal efficiency depends on precise investigations of the combustion and flow characteristics inside a furnace. Especially, the flow field of the hot gas has significant influence on heating slabs. The slabs are heated up to the temperature over 1500. K, and then they are transported to the rolling mill. The heating efficiency is affected by many factors,

Managing agricultural change for biodiversity conservation in a Mediterranean upland

In Europe, land use changes follow public policies, and particularly the Common Agricultural Policy. To predict the effect of policies on agricultural practices, landscape, and ultimately biodiversity, requires understanding of the interactions between social, economic and ecological dynamics at regional scale. We studied by means of prospective scenarios the possible effects of agricultural chang

Modelling invasibility in endogenously oscillating tree populations : Timing of invasion matters

The timing of introduction of a new species into an ecosystem can be critical in determining the invasibility (i.e. the sensitivity to invasion) of a resident population. Here, we use an individual-based model to test how (1) the type of competition (symmetric versus asymmetric) and (2) seed masting influence the success of invasion by producing oscillatory dynamics in resident tree populations. W

Roller coaster loop shapes revisited

In 'Rollercoaster loop shapes', (Pendrill 2005 Phys. Educ. 40 517) the author started from the observation that although textbook loops are often circular, real rollercoaster loops are not. In this paper the mathematical description of various possible loop shapes, as well as their riding properties was discussed and also how a study of loop shapes can be used in physics education.

Liquid in accelerated motion

What happens to a liquid in a swing or a loop? Accelerated motions leadto effects that may seem surprising. Consider a liquid in a glass placed ona wooden triangle, in turn attached to a string and moving fast in circle a vertical plane. The surface of the water remains parallel to the bottom of the glass—and orthogonal to the string—as long as gravity and the tension in the string are the only fo

Municipal governance and sustainability : The role of local governments in promoting transitions

This research addresses local governance for building energy efficiency. In order to turn an increasingly proactive environmental policy agenda at subnational levels into practice, local governments experiment with new forms of governance. One important policy area in this regard is building energy use, often addressed through urban development projects. Such initiatives provide important insight

The rate of joint replacement in osteoarthritis depends on the patient's socioeconomic status : a cohort study of 71,380 patients

Background and purpose - Assessment of potential disparities in access to care is a vital part of achieving equity in health and healthcare. We have therefore studied the effect of socioeconomic status (SES) on the rates of knee and hip replacement due to osteoarthritis. Methods - This was a cohort study in Skåne, Sweden. We included all residents aged ≥ 35 years with consultations between 2004 an