The evolution of parental care in insects: A test of current hypotheses.

Which sex should care for offspring is a fundamental question in evolution. Invertebrates, and insects in particular, show some of the most diverse kinds of parental care of all animals, but to date there has been no broad comparative study of the evolution of parental care in this group. Here, we test existing hypotheses of insect parental care evolution using a literature-compiled phylogeny of over 2000 species. To address substantial uncertainty in the insect phylogeny, we use a brute force approach based on multiple random resolutions of uncertain nodes. The main transitions were between no care (the probable ancestral state) and female care. Male care evolved exclusively from no care, supporting models where mating opportunity costs for caring males are reduced-for example, by caring for multiple broods-but rejecting the "enhanced fecundity" hypothesis that male care is favored because it allows females to avoid care costs. Biparental care largely arose by males joining caring females, and was more labile in Holometabola than in Hemimetabola. Insect care evolution most closely resembled amphibian care in general trajectory. Integrating these findings with the wealth of life history and ecological data in insects will allow testing of a rich vein of existing hypotheses.We thank S. T. Trumbo, D. Lukas, and T. L. Gluckman for advice and helpful comments on the manuscript; K. Isvaran, S. Qader, S. Ho, L. Revell, R. Maia, R. FitzJohn, and A. Meade for invaluable statistical advice; A. Seago, G. Dury, B. Kranz, and L. A. Mound for points of information; andO.F. Time for solving all problems. This studywas funded by BBSRC studentship 02/A1/S/8091 to JDJG. The authors declare no conflicts of interest.This is the final published version. It was first made available by Wiley at http://onlinelibrary.wiley.com/doi/10.1111/evo.12656/suppinfo

An Improved Method for the Large-Scale Processing of Woad (Isatis tinctoria) for Possible Commercial Production of Woad Indigo

The increasing use of alternative crops has meant the introduction of new technologies to process their products. In this work, an alternative method is presented for the extraction of natural indigo from woad (Isatis tinctoria) based on a technique used to extract indigo from Indigofera spp. This method does not rely on the old fermentation procedure used throughout Northern Europe and is cheap, clean and efficient. Evolved from laboratory-based tests, it involves steeping the leaves at low pH in warm water and extracting the indigo at a higher pH, followed by ultra-filtration of the product, which is then left to air-dry. Problems encountered during the development of the technique and how they were overcome are discussed. © 1998 Silsoe Research Institute

Via and embedded resistor production in low cost lithographically printed substrates

Lithographic printing of silver based conductive inks to form circuit tracking provides a very low cost, environmentally friendly method of production. It allows circuits with line widths down to 100 μm and a sheet resistance of 0.3 Ω per square to be produced at rates of up to 10000 impressions per hour. The process makes use of low capital cost equipment and has low set up costs. To date, an equally cost effective method of manufacturing vias in these circuits has not been developed. This paper proposes two new techniques for via production which are compatible with the rest of the manufacturing process. In the first technique, suitably profiled holes are laser drilled for subsequent filling as part of the lithographic printing. In the second technique laser energy is used to melt the substrate material so that it is able to mix with the conductive ink and so form a conductive path. The paper describes the proposed production techniques and discusses the factors affecting each method and in particular the substrate properties affecting production. The substrate materials considered in detail are Glossart and Teslin. The optical absorption and ablation characteristics of these materials for excimer and CO2 lasers are reported, as are the thermal diffusivities

Detecting brute-force attacks on cryptocurrency wallets

Blockchain is a distributed ledger, which is protected against malicious modifications by means of cryptographic tools, e.g. digital signatures and hash functions. One of the most prominent applications of blockchains is cryptocurrencies, such as Bitcoin. In this work, we consider a particular attack on wallets for collecting assets in a cryptocurrency network based on brute-force search attacks. Using Bitcoin as an example, we demonstrate that if the attack is implemented successfully, a legitimate user is able to prove that fact of this attack with a high probability. We also consider two options for modification of existing cryptocurrency protocols for dealing with this type of attacks. First, we discuss a modification that requires introducing changes in the Bitcoin protocol and allows diminishing the motivation to attack wallets. Second, an alternative option is the construction of special smart-contracts, which reward the users for providing evidence of the brute-force attack. The execution of this smart-contract can work as an automatic alarm that the employed cryptographic mechanisms, and (particularly) hash functions, have an evident vulnerability.Comment: 10 pages, 2 figures; published versio

Causes of death in the decade after hospitalisation for injury during adolescence: a study using linked hospital admissions and death registrations data

OBJECTIVES: To quantify risks of cause-specific death up to ten years after discharge from an emergency admission to hospital for violent, self-inflicted, or drug/alcohol-related injury, during adolescence. To compare these risks by type of original injury, and with risks after accident-related injury. APPROACH: We used admissions data for England linked to death registrations from 1997 to 2012. We identified emergency admissions for injury in 10-19y olds and categorised type of injury as either violent, self-inflicted, drug/alcohol-related, or accident-related (no record of violent, self-inflicted, or drug/alcohol-related injury, but record of an accident), using ICD-10 codes in admission records. We categorised causes of death as homicide, suicide, drug/alcohol-related, accidental (excluding drug/alcohol-related accidents), or ‘other’ (remaining causes), using ICD-9 and ICD-10 codes from death registration records. We estimated cumulative risks of cause-specific death in the ten years after discharge, by sex and type of original injury. We used time-to-event regression models to estimate risks of cause-specific death, after violent, self-inflicted or drug/alcohol-related injury (relative to those after accident-related injury), adjusted for age-group (10-15, 16-17, 18-19y) and chronic condition status (yes/no; indicated by ICD-10 codes in past year admission records), and stratified by sex. RESULTS: There were 333,009 adolescents admitted for violent, self-inflicted, or drug/alcohol-related injury (girls 181,926, boys 181,053), and 649,818 for accident-related injury (girls 166,462, boys 483,356). There were 4,782 deaths in the ten years after discharge: 2,415 after violent, self-inflicted or drug/alcohol-related injury (girls 873, boys 1,542) and 2,367 after accident-related injury (girls 439, boys 1,928). Deaths after violent, self-inflicted or drug/alcohol-related injury injury were mostly accounted for by suicide (girls 35.8% of all deaths, boys 34.2%) or drug/alcohol-related death (girls 31.7%, boys 35.6%). Risks of suicide were similar to those for drug/alcohol-related death, regardless of the type of original injury. Adjusted risks of death were 1.4 to 6.8 times greater than after accident-related injury (by cause and sex). CONCLUSION: Adolescent girls and boys discharged after violent, self-inflicted, or drug/alcohol-related injury had similar risks of suicide and drug/alcohol related death, regardless of the category of the original injury. These adolescents also had increased risks of cause-specific deaths compared to those discharged after accident-related injury. Current practice to assess and reduce risks of future harm after self-inflicted injury should be extended to adolescents discharged after violent or drug/alcohol-related injury. Preventive strategies should address risks of drug/alcohol-related death as well as risks of suicide

Male genital titillators and the intensity of post-copulatory sexual selection across bushcrickets

Animal genitalia are diverse and a growing body of evidence suggests that they evolve rapidly under post-copulatory sexual selection. This process is predicted to be more intense in polyandrous species, although there have been very few comparative studies of the relationship between the complexity of genital structures in males and measures of the degree of polyandry. In some bushcricket families, males possess sclerotised copulatory structures known as titillators, which are inserted into the female’s genital chamber and moved rhythmically. Like other genital structures, bushcricket titillators are widely used as important taxonomic characters and show considerable variation across species in structure, shape and the extent to which they are spined. Here, we examine relationships between the presence/absence of titillators, titillator complexity and both mating frequency and the degree of polyandry in bushcrickets, using phylogenetic comparative analyses. Using published sources combined with original observations, data were obtained for the mean level of polyandry, the duration of the male and female sexual refractory periods and the level of complexity of titillators. To analyse data, we fitted phylogenetic generalised least squares models. No significant relationships were found between titillator presence or complexity and either the level of polyandry, duration of the male’s sexual refractory period or the ratio of the female and male sexual refractory periods. The duration of the female’s refractory period, however, was positively associated with titillator presence and negatively associated with titillator complexity. The data therefore partially support the hypothesis that post-copulatory sexual selection drives genital evolution in this taxon

Global data for ecology and epidemiology: a novel algorithm for temporal Fourier processing MODIS data

Background. Remotely-sensed environmental data from earth-orbiting satellites are increasingly used to model the distribution and abundance of both plant and animal species, especially those of economic or conservation importance. Time series of data from the MODerate-resolution Imaging Spectroradiometer (MODIS) sensors on-board NASA's Terra and Aqua satellites offer the potential to capture environmental thermal and vegetation seasonality, through temporal Fourier analysis, more accurately than was previously possible using the NOAA Advanced Very High Resolution Radiometer (AVHRR) sensor data. MODIS data are composited over 8- or 16-day time intervals that pose unique problems for temporal Fourier analysis. Applying standard techniques to MODIS data can introduce errors of up to 30% in the estimation of the amplitudes and phases of the Fourier harmonics. Methodology/Principal Findings. We present a novel spline-based algorithm that overcomes the processing problems of composited MODIS data. The algorithm is tested on artificial data generated using randomly selected values of both amplitudes and phases, and provides an accurate estimate of the input variables under all conditions. The algorithm was then applied to produce layers that capture the seasonality in MODIS data for the period from 2001 to 2005. Conclusions/Significance. Global temporal Fourier processed images of 1 km MODIS data for Middle Infrared Reflectance, day- and night-time Land Surface Temperature (LST), Normalised Difference Vegetation Index (NDVI), and Enhanced Vegetation Index (EVI) are presented for ecological and epidemiological applications. The finer spatial and temporal resolution, combined with the greater geolocational and spectral accuracy of the MODIS instruments, compared with previous multi-temporal data sets, mean that these data may be used with greater confidence in species' distribution modelling

Clustering and the hyperbolic geometry of complex networks

Clustering is a fundamental property of complex networks and it is the mathematical expression of a ubiquitous phenomenon that arises in various types of self-organized networks such as biological networks, computer networks or social networks. In this paper, we consider what is called the global clustering coefficient of random graphs on the hyperbolic plane. This model of random graphs was proposed recently by Krioukov et al. as a mathematical model of complex networks, under the fundamental assumption that hyperbolic geometry underlies the structure of these networks. We give a rigorous analysis of clustering and characterize the global clustering coefficient in terms of the parameters of the model. We show how the global clustering coefficient can be tuned by these parameters and we give an explicit formula for this function.Comment: 51 pages, 1 figur

Exploring the experiences of social workers in working with children suspected of having fetal alcohol spectrum disorders

Fetal alcohol spectrum disorder (FASD) is one outcome from prenatal alcohol exposure. Social workers are likely to encounter children with the condition, due to the greater likelihood of prenatal alcohol exposure among children in social services settings. This study explores the experiences of social workers in working with children suspected of having FASD and the support offered to social workers, the children and their families. Semi-structured interviews followed by qualitative framework analysis were conducted with seven child and family social workers along with one child protection solicitor who had experience of handling FASD cases. The two main themes that emerged from the data were a lack of knowledge about FASD and the paucity of diagnosis. Lack of knowledge among the social workers was linked to difficulty in managing children suspected to have the condition, feelings of frustration and normalisation of challenging behaviours. The paucity of diagnosis led to an under-emphasis of FASD in assessments, a dearth of specialist services and confusion about its specific effects in contexts of multiple substance misuse and harmful socio-environmental factors. The need for increased FASD awareness within social services and the development of FASD-targeted support for children and families is highlighted. Social workers would benefit from the inclusion of FASD-focused training in their curricula and professional development plans. Improving the diagnostic capacities of health institutions would address the paucity of diagnosis and raise the profile of FASD, especially in the social services setting