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Animal colouration is often a trade-off between background matching for camouflage from predators, and conspicuousness for communication with con- or heterospecifics. Stomatopods are marine crustaceans known to use colour signals during courtship and contests, while their overall body colouration may provide camouflage. However, we have little understanding of how stomatopods perceive these signal

Fan worms (Annelida: Sabellidae) possess compound eyes and other photoreceptors on their radiolar feeding tentacles. These eyes putatively serve as an alarm system that alerts the worm to encroaching threats, eliciting a rapid defensive retraction into their protective tube. The structure and independent evolutionary derivation of these radiolar eyes make them a fascinating target for exploring th

Stomatopod crustaceans are renowned for their elaborate visual systems. Their eyes contain a plethora of photoreceptors specialized for chromatic and polarization detection, including several that are sensitive to varying wavelength ranges and angles of polarization within the ultraviolet (UV) range (less than 400 nm). Behavioural experiments have previously suggested that UV photoreception plays

BACKGROUND: Sabellarids, also known as honeycomb or sandcastle worms, when building their tubes, produce chemical signals (free fatty acids) that are responsible for larval settlement and the formation of three-dimensional aggregations. The larval palps and the dorsal hump (becoming the median organ in adults) are presumed to participate in such a substrate selection during settlement. Notably, th

Most stomatopod crustaceans have complex retinas in their compound eyes, with up to 16 spectral types of photoreceptors, but members of the superfamily Squilloidea have much simpler retinas, thought to contain a single photoreceptor spectral class. In the Atlantic stomatopod Squilla empusa, microspectrophotometry shows that all photoreceptors absorb light maximally at 517 nm, indicating that a sin

We review the visual systems of crustacean larvae, concentrating on the compound eyes of decapod and stomatopod larvae as well as the functional and behavioral aspects of their vision. Larval compound eyes of these macrurans are all built on fundamentally the same optical plan, the transparent apposition eye, which is eminently suitable for modification into the abundantly diverse optical systems

Stomatopod crustaceans employ unique ultraviolet (UV) optical filters in order to tune the spectral sensitivities of their UV-sensitive photoreceptors. In the stomatopod species Neogonodactylus oerstedii, we previously found four filter types, produced by five distinct mycosporine-like amino acid pigments in the crystalline cones of their specialized midband ommatidial facets. This UV-spectral tun

Stomatopod crustaceans have the most complex and diverse assortment of retinal photoreceptors of any animals, with 16 functional classes. The receptor classes are subdivided into sets responsible for ultraviolet vision, spatial vision, colour vision and polarization vision. Many of these receptor classes are spectrally tuned by filtering pigments located in photoreceptors or overlying optical elem

Opsin proteins are essential molecules in mediating the ability of animals to detect and use light for diverse biological functions. Therefore, understanding the evolutionary history of opsins is key to understanding the evolution of light detection and photoreception in animals. As genomic data have appeared and rapidly expanded in quantity, it has become possible to analyse opsins that functiona

Stomatopod crustaceans possess apposition compound eyes that contain more photoreceptor types than any other animal described. While the anatomy and physiology of this complexity have been studied for more than two decades, few studies have investigated the molecular aspects underlying the stomatopod visual complexity. Based on previous studies of the structure and function of the different types

Stomatopod crustaceans have the most complex assemblage of visual receptor classes known; retinas of many species are thought to express up to 16 different visual pigments. Physiological studies indicate that stomatopods contain up to six distinct middle-wavelength-sensitive (MWS) photoreceptor classes, suggesting that no more than six different MWS opsin gene copies exist per species. However, we

In 2007, a research program was launched to provide an overview of research needs coupled to arson in Swedish schools. A total of six different Swedish universities and research institutes were involved in different projects in the ensuing research program. These projects involved both technical aspects such as fire detection and fire protection as well as sociological issues related to individual

AIM: Schizophrenia is associated with high cardiovascular mortality predominantly as a result of acute coronary syndrome (ACS). The aim of this study is to analyze time trends of coronary procedures, guideline-based therapy, and all-cause mortality in patients diagnosed with schizophrenia.METHODS AND RESULTS: This Danish nationwide register-based study analyzed 734 patients with a baseline diagnos

Denna avhandling behandlar konstruktionen satsradning. Det avser ett fall av två huvudsatser som följer varandra i samma grafiska mening utan att skiljas av konjunktion, t.ex. och eller men. Satserna kan skiljas av kommatecken men inte av något annat litet skiljetecken som semikolon eller kolon. I avhandlingen undersöks satsradning såväl teoretiskt som empiriskt med utgångspunkt i gymnasieelevers The topic of this thesis is the construction labelled satsradning in Swedish, which typically corresponds to the English term comma splice. They signify a case of two syntactically independent (main) clauses which are joined in the same orthographic sentence, without a coordinating conjunction. The two clauses can either be separated by a comma or joined together with no punctuation mark at all.Th

In this paper we introduce the notion of complex isoparametric functions on Riemannian manifolds. These are then employed to devise a general method for constructing proper r-harmonic functions. We then apply this to construct the first known explicit proper r-harmonic functions on the Lie group semidirect products Rm⋉ Rn and Rm⋉ H 2n+1, where H 2n+1 denotes the classical (2 n+ 1) -dimensional Hei

Vehicle fires in tunnels can have catastrophic consequences for the road users, the property and traffic infrastructure. To support an evacuation planning, this study simulates the fire smoke toxicity and the smoke layer of a vehicle fire in a full-size test tunnel. The three dimensional prediction of the fire smoke toxicity in the test tunnel is realized by implementing the Fractional Effective D

We study left-invariant foliations F on Riemannian Lie groups G generated by a subgroup K. We are interested in such foliations which are conformal and with minimal leaves of codimension two. We classify such foliations F when the subgroup K is one of the important SU(2)*SU(2), SU(2)*SL_2(R), SU(2)*SO(2) or SL_2(R)*SO(2). By this we yield new multi-dimensional families of Lie groups G carrying suc

Objective – Gothenburg University Library has implemented a process with the goal to combine quality assurance and strategic planning activities. The process has bottom-up and top-down features designed to generate strong staff-involvement and long-term strategic stability.Methods – In 2008 the library started implementing a system in which each library team should state a number of improvement ac

Library assessment and external intelligence is important for tracking and improving library activities. Quality assurance and strategic planning are intricate parts in sustainably developing better and more effective services. Gothenburg University Library has implemented a process with the goal to join these activities. The process has both bottom-up and top-down features designed to generate st