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Thresholds and noise limitations of colour vision in dim light

Colour discrimination is based on opponent photoreceptor interactions, and limited by receptor noise. In dim light, photon shot noise impairs colour vision, and in vertebrates, the absolute threshold of colour vision is set by dark noise in cones. Nocturnal insects (e.g. moths and nocturnal bees) and vertebrates lacking rods (geckos) have adaptations to reduce receptor noise and use chromatic visi

The remarkable visual capacities of nocturnal insects : Vision at the limits with small eyes and tiny brains

Nocturnal insects have evolved remarkable visual capacities, despite small eyes and tiny brains. They can see colour, control flight and land, react to faint movements in their environment, navigate using dim celestial cues and find their way home after a long and tortuous foraging trip using learned visual landmarks. These impressive visual abilities occur at light levels when only a trickle of p

Labor market consequences of growing up with a sibling with type 1-diabetes

Economic research on child health and future labor market outcomes has mainly focused on children with impaired health themselves, and only recently begun to assess spillover effects for siblings. Yet, the challenge to accommodate a family's routines within the requirements of a complex and time-consuming disease is most likely to spillover on siblings. While the burden of ill health and managing

Origins of inhabitants from the 16th century Sala (Sweden) silver mine cemetery – A lead isotope perspective

Historical documents record the operation of a silver mine from the 16th century AD located near the former village of Salberget in central Sweden. The historical record describes several categories of inhabitants, including local families, workers and miners, foreign engineers and mining specialists, as well as war captives and criminals used as forced labor in the mines. A church yard in the vic

Influence of nanomechanical stress induced by ZnO nanoparticles of different shapes on the viability of cells

There is growing interest in nanostructures interacting with living organisms. However, there are still no general rules for the design of biocompatible nanodevices. Here, we present a step towards understanding the interactions between nanostructures and living cells. We study the influence of nanomechanical stress induced by zinc oxide (ZnO) nanostructures of different shapes on the viability of

The combined effect of wetting ability and durability on outdoor performance of wood : development and verification of a new prediction approach

Comprehensive approaches to predict performance of wood products are requested by international standards, and the first attempts have been made in the frame of European research projects. However, there is still an imminent need for a methodology to implement the durability and moisture performance of wood in an engineering design method and performance classification system. The aim of this stud

Mesoscale ordering in binary aqueous solvents induced by ion size asymmetry

Surprising weak assembly behavior has lately been found in binary aqueous solvents containing antagonistic salt. The underlying mechanism is still under debate, particularly the role of ion size asymmetry. Here we use small-angle X-ray scattering to study the effect of ion size asymmetry on the mesoscale ordering in a binary solvent composed of water and 2,6-dimethylpyridine with added symmetrical

An innovative approach to predict technology evolution for the desoldering of printed circuit boards : A perspective from China and America

The printed circuit boards basis of electronic equipment have seen a rapid growth in recent years and played a significant role in modern life. Nowadays, the fact that electronic devices upgrade quickly necessitates a proper management of waste printed circuit boards. Non-destructive desoldering of waste printed circuit boards becomes the first and the most crucial step towards recycling electroni

On a sharp estimate for hankel operators and Putnam's inequality

We obtain a sharp norm estimate for Hankel operators with anti-analytic symbol for weighted Bergman spaces. For the classical Bergman space, the estimate improves the corresponding classical Putnam inequality for commutators of Toeplitz operators with analytic symbol by a factor of 1/2, answering a recent conjecture by Bell, Ferguson and Lundberg. As an application, this yields a new proof of the

Newton maps as matings of cubic polynomials

In this paper, we prove existence and uniqueness of matings of a large class of renormalizable cubic polynomials with one fixed critical point and the other cubic polynomial having two fixed critical points. The resulting mating is a Newton map. Our result is the first part toward a conjecture by L. Tan, stating that all (cubic) Newton maps can be described as matings or captures.

Liver-first strategy for synchronous colorectal liver metastases : an intention-to-treat analysis

Background The liver-first strategy signifies resection of liver metastases before the primary colorectal cancer. The aim of the present study was to compare failure to complete intended treatment and survival in liver-first and classical strategies. Methods All patients with colorectal cancer and synchronous liver metastases planned for sequential radical surgery in a single institution between 2

Business Cycle Synchronization In Europe : Evidence From The Scandinavian Currency Union

In this paper we study business cycle synchronization in the three Scandinavian countries Denmark, Norway and Sweden prior to, during and after the Scandinavian Currency Union 1873–1913. We find that the degree of synchronization tended to increase during the currency union, thus supporting earlier empirical evidence. Estimates of factor models suggest that common Scandinavian shocks are important

The impact of salinity on the microbial response to drying and rewetting in soil

In saline soils, the severity of drought for the soil microbial community is exacerbated by accumulating concentrations of salts during drying. In this study we investigated how bacterial growth and respiration responses to drying-rewetting were affected by salinity. To do this, we adjusted a non-saline soil to four different salinities (0, 2, 7 and 22 mg NaCl g−1), followed by addition of plant m

Investigating solar energy potential in tropical urban environment : A case study of Dar es Salaam, Tanzania

Solar energy is considered to be an alternative sustainable energy source in the urban environment. The potential of using solar energy in urban areas is highly dependent on urban morphology which affects the level of solar irradiance received by individual buildings. Many studies focus on solar energy potential of building form in urban areas but relatively few studies examine how urban morpholog

Study on ignition and flame development in gasoline partially premixed combustion using multiple optical diagnostics

Gasoline partially premixed combustion (PPC) is a potential strategy to achieve high engine efficiency, as well as low NOx and soot emissions. But the in-cylinder combustion process of PPC is not well understood. In this paper, multiple optical diagnostics are applied to investigate the PPC ignition and flame development in a light-duty optical engine under single-injection condition. For the inje