Quantification of marine benthic communities with metabarcoding

DNA metabarcoding methods have been implemented in studies aimed at detecting and quantifying marine benthic biodiversity. In such surveys, universal barcodes are amplified and sequenced from environmental DNA. To quantify biodiversity with DNA metabarcoding, a relation between the number of DNA sequences of a species and its biomass and/or the abundance is required. However, this relationship is complicated by many factors, and it is often unknown. In this study, we validate estimates of biomass and abundance from molecular approaches with those from the traditional morphological approach. Abundance and biomass were quantified from 126 samples of benthic intertidal mudflat using traditional morphological approaches and compared with frequency of occurrence and relative read abundance estimates from a molecular approach. A relationship between biomass and relative read abundance was found for two widely dispersed annelid taxa (Pygospio and Scoloplos). None of the other taxons, however, showed such a relationship. We discuss how quantification of abundance and biomass using molecular approaches are hampered by the ecology of DNA i.e. all the processes that determine the amount of DNA in the environment, including the ecology of the benthic species as well as the compositional nature of sequencing data

What works: Psychosociale dienstverlening Slachtofferhulp Nederland

Samenvatting Het doel van dit onderzoek is drieledig. Ten eerste een inventarisatie maken van de beleidstheorie van het huidige slachtofferbeleid met focus op beleid dat gericht is op de psychische gezondheid van slachtoffers. Ten tweede inzicht verkrijgen in het emotionele/psychische hulpaanbod vanuit Slachtofferhulp Nederland (SHN) aan slachtoffers van ernstige geweld- en zedendelicten (EGZ), inclusief doorverwijzing naar bijvoorbeeld psychologische zorgverlening. Tenslotte is het doel te inventariseren wat in de wetenschappelijke literatuur bekend is over het type behandeling- gericht op psychische klachten- dat effectief is voor EGZ-slachtoffers. Summary The aim of this study was to determine what type of psychosocial support is offered by Victim Support Netherlands (Slachtofferhulp Nederland; SHN) to victims of serious violent and sexual crimes (EGZ cases); together with any theories underlying its policy, and to investigate whether the support offered is in line with what is known in current scientific literature. We divided the research into a number of sub-studies, in which various methods were used: desk research; interviews with SHN employees; interviews with victims; a survey among former clients; and research in SHN's registration systems

Experimental tests of a seasonally changing visual preference for habitat in a long-distance migratory shorebird

Migratory shorebirds show highly organized seasonal cycles in physiological and morphological traits (body mass and composition, plumage, hormone levels, etc.), which in captivity is accompanied by restless behaviour at times when free-living birds would start migration. We introduce the idea that seasonally changing preference for habitat could motivate migrants to embark on migration and that this cognitive process could also guide them to seasonally appropriate places. We explored this by testing whether red knots (Calidris canutus), which also in captivity maintain marked circannual phenotypic rhythms, show evidence of seasonal change in preference for pictures of seasonally appropriate habitats. We first developed a method to verify whether red knots are able to memorize and discriminate contrasting pictures projected by LCD projectors. This was followed by two different experiments in which we tested for a seasonally changing preference for breeding or non-breeding habitat. When carried out during the pre-breeding season, the red knots are expected to prefer pictures of mudflats, their non-breeding habitat. At the start of the breeding season, they should prefer pictures of the tundra breeding habitat. We established that knots are able to distinguish and memorize projected images. We failed to demonstrate the predicted change in vision-based habitat preference, but for reasons of test design we do not interpret this as a strong rejection of the hypothesis. Instead, we suggest that experiments with greater numbers of individuals tested once, perhaps in combination with the provision of additional cues such as smells and sounds, will help the development of these ideas further

New generation hole transporting materials for perovskite solar cells: amide-based small-molecules with nonconjugated backbones

State‐of‐the‐art perovskite‐based solar cells employ expensive, organic hole transporting materials (HTMs) such as Spiro‐OMeTAD that, in turn, limits the commercialization of this promising technology. Herein an HTM (EDOT‐Amide‐TPA) is reported in which a functional amide‐based backbone is introduced, which allows this material to be synthesized in a simple condensation reaction with an estimated cost of <$5 g−1. When employed in perovskite solar cells, EDOT‐Amide‐TPA demonstrates stabilized power conversion efficiencies up to 20.0% and reproducibly outperforms Spiro‐OMeTAD in direct comparisons. Time resolved microwave conductivity measurements indicate that the observed improvement originates from a faster hole injection rate from the perovskite to EDOT‐Amide‐TPA. Additionally, the devices exhibit an improved lifetime, which is assigned to the coordination of the amide bond to the Li‐additive, offering a novel strategy to hamper the migration of additives. It is shown that, despite the lack of a conjugated backbone, the amide‐based HTM can outperform state‐of‐the‐art HTMs at a fraction of the cost, thereby providing a novel set of design strategies to develop new, low‐cost HTMs

The role of heart rate levels in the intergenerational transmission of crime

Several prospective multigenerational studies have shown that crime runs in the family, while empirical research on the biological causes of crime has also established that low heart rate is related to antisocial behavior. This study examines whether the intergenerational transmission of crime is moderated or mediated by a low heart rate of the son. Prospectively collected conviction data on 794 men from three consecutive generations of the Dutch Transfive dataset is used. Heart rates were measured around age 18, during the medical examination prior to the mandatory military service in the Dutch army. All analyses were conducted separately for violent and non-violent crime. Both paternal violence and low heart rate levels are associated with increased violent offending. Intergenerational transmission of violence was only found among families in which the son had a low heart rate, although the degree of transmission did not differ significantly from families in which the son had a high heart rate. No support was found for a mediating influence of low heart rates of criminals’ offspring on the intergenerational transmission of crime and violence. The results from this study underline the importance to focus on the interaction between biological risk factors and psychosocial risk factors for criminal behaviorFdR – Publicaties niet-programma gebonde

Cholestase bij pasgeborenen als gevolg van parenterale voeding

Toediening van totale parenterale voeding (TPN) aan pasgeborenen is geassocieerd met het ontstaan van cholestase. Ondanks intensief onderzoek zijn de pathofysiologische mechanismen slechts gedeeltelijk opgehelderd. In dit artikel wordt ingegaan op de huidige inzichten in de risicofactoren die geassocieerd zijn met TPN-cholestase bij pasgeborenen, de specifieke bestanddelen en deficiënties van TPN die cholestase kunnen veroorzaken, de mogelijke relatie met de ‘fysiologische cholestase van de pasgeborene’, die de pasgeborene kwetsbaarder maakt voor potentieel hepatotoxische stoffen, en de transportsystemen in de levercelmembraan die betrokken zijn bij galvorming. De hypothese dat ‘cholestatische galzuren’ een rol spelen in de etiologie van TPN-cholestase en de therapeutische mogelijkheden worden besproken.Administration of total parenteral nutrition (TPN) to neonates is associated with the occurrence of cholestasis. Despite intensive research, the pathophysiological mechanisms have not been elucidated. In this review we describe the present insights into the risk factors for the development of TPN-associated cholestasis, the specific components or lack of components (deficiencies) in TPN that can cause cholestasis, the possible correlation with 'physiologic cholestasis of the neonate', which makes the infant more susceptible for potentially hepatotoxic compounds, and the transport systems in the liver cell membrane which are involved in bile formation. The hypothesis that 'cholestatic bile salts' play a role in the etiology of TPN-related cholestasis and the therapeutic options will be discussed.</p

New generation hole transporting materials for perovskite solar cells: amide-based small-molecules with nonconjugated backbones

State‐of‐the‐art perovskite‐based solar cells employ expensive, organic hole transporting materials (HTMs) such as Spiro‐OMeTAD that, in turn, limits the commercialization of this promising technology. Herein an HTM (EDOT‐Amide‐TPA) is reported in which a functional amide‐based backbone is introduced, which allows this material to be synthesized in a simple condensation reaction with an estimated cost of &lt;$5 g−1. When employed in perovskite solar cells, EDOT‐Amide‐TPA demonstrates stabilized power conversion efficiencies up to 20.0% and reproducibly outperforms Spiro‐OMeTAD in direct comparisons. Time resolved microwave conductivity measurements indicate that the observed improvement originates from a faster hole injection rate from the perovskite to EDOT‐Amide‐TPA. Additionally, the devices exhibit an improved lifetime, which is assigned to the coordination of the amide bond to the Li‐additive, offering a novel strategy to hamper the migration of additives. It is shown that, despite the lack of a conjugated backbone, the amide‐based HTM can outperform state‐of‐the‐art HTMs at a fraction of the cost, thereby providing a novel set of design strategies to develop new, low‐cost HTMs