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Social inequalities in young people’s conduct problems: informing intervention development
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Understanding the relationship between family income and conduct problems: findings from the mental health of children and young people survey
Full text linkBackground:
Children from low-socioeconomic backgrounds exhibit more behavioural difficulties than those from more affluent families. Influential theoretical models specify family stress and child characteristics as mediating this effect. These accounts, however, have often been based on cross-sectional data or longitudinal analyses that do not capture all potential pathways, and therefore may not provide good policy guidance.
Methods:
In a UK representative sample of 2399 children aged 5–15, we tested mediation of the effect of household income on parent and teacher reports of conduct problems (CP) via unhealthy family functioning, poor parental mental health, stressful life events, child physical health and reading ability. We applied cross-lagged longitudinal mediation models which allowed for testing of reciprocal effects whereby the hypothesised mediators were modelled as outcomes as well as predictors of CP.
Results:
We found the predicted significant longitudinal effect of income on CP, but no evidence that it was mediated by the child and family factors included in the study. Instead, we found significant indirect paths from income to parental mental health, child physical health and stressful life events that were transmitted via child CP.
Conclusion:
The results confirm that income is associated with change in CP but do not support models that suggest this effect is transmitted via unhealthy family functioning, parental mental health, child physical health, stressful life events or reading difficulties. Instead, the results highlight that child CP may be a mediator of social inequalities in family psychosocial functioning
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Combustion properties of biomass residues rich in phosphorus
Full text linkTillgången på traditionella biobränslen är begränsad och därför behöver man ta fram nya, tidigare outnyttjade biobränslen för att möta de uppställda CO2 emissionsmålen av EU och det ständigt ökande energibehovet. Under de senare åren har intresset riktats mot termisk energiutvinning ur olika restfraktioner och avfall.
Vid produktion av fordonsbränsle ur biomassa är den fasta restprodukten ofta den största procesströmmen i produktionsanläggningen. En riktig hantering av restprodukterna skulle göra produktionen mera lönsam och mer ekologiskt hållbar. Ett alternativ är att genom förbränning producera elektricitet och/eller värme eftersom dessa restprodukter anses som CO2-neutrala.
Målsättningen med den här avhandlingen var att studera förbränningsegenskaperna hos några fasta restprodukter som uppstår vid framställning av förnybara fordonsbränslen. De fyra undersökta materialen är rapskaka, palmkärnskaka, torkad drank och stabiliserat rötslam. I studien används ett stort urval av undersökningsmetoder, från laboratorieskala till fullskalig förbränning, för att identifiera de huvudsakliga utmaningarna förknippade med förbränning av restprodukterna i pannor med fluidiserad bäddteknik.
Med hjälp av detaljerad bränslekarakterisering kunde restprodukterna konstateras vara en värdefull källa för värme- och elproduktion. Den kemiska sammansättningen av restprodukterna varierar stort jämfört med mera traditionellt använda biobränslen. En gemensam faktor för alla de studerade restprodukterna är en hög fosforhalt. På grund av de låga fosforkoncentrationerna i de traditionella biobränslena har grundämnet hittills inte ansetts spela någon större roll i askkemin. Experimenten visade nu att fosfor inte mera kan försummas då man studerar kemin i förbränningsprocesser, då allt flera fosforrika bränslen tränger in på energimarknaden.Perinteisten biopolttoaineiden saatavuus on rajallinen ja näin ollen tarvitaan uusia hyödyntämättömiä biopolttoaineita, jotta EU:n CO2-päästötavoitteet saavutettaisiin ja kasvava energian tarve voitaisiin tyydyttää. Viime vuosina kiinnostus on kohdistunut jätteen ja jäännösmateriaalin hyötykäytöstä energianlähteenä.
Nestemäisen biopolttoaineen valmistuksessa suurin prosessivirta tuotantolaitoksesta on usein kiinteää jäännösmateriaalia. Jäännösmateriaalin oikeanlainen hyödyntäminen parantaisi valmistuksen kannattavuutta sekä kestävää kehitystä. Vaihtoehtona on tuottaa sähköä ja lämpöä polttamalla jäännösmateriaalia, sillä se luokitellaan CO2-neutraaliksi.
Tämän tutkielman tavoitteena oli selvittää nestemäisen biopolttoaineen valmistuksessa syntyvän neljän eri kiinteän jäännösmateriaalin polttokäyttäytymistä. Tutkitut jäännösmateriaalit olivat: rapsikakku, palmunydinkakku, tislaussakka sekä viemäriliete. Tutkimuksessa käytettiin monia eri tutkimusmenetelmiä, aina laboratoriolaitteista pienikokoiseen polttolaitokseen. Täten pystyttiin kartoittamaan mahdolliset haasteet, joita kohdataan kyseessä olevien jäännösmateriaalien leijupetipoltossa.
Tarkan polttoainekarakterisoinnin ansiosta pystyttiin todentamaan, että jäännösmateriaalit ovat arvokas lähde energian- ja sähköntuotantoon. Jäännösmateriaalien kemiallinen koostumus eroaa suuresti perinteisistä biopolttoaineista. Yhdistävänä tekijänä kyseisillä jäännösmateriaaleilla oli korkea fosforipitoisuus. Perinteisillä biopolttoaineilla on alhainen fosforipitoisuus ja näin ollen fosforin merkitystä tuhkakemiaan ei ole pidetty oleellisena. Tulokset osoittavat, että fosforin merkitystä ei voida vähätellä tutkittaessa kemiaa polttoprosesseissa, fosforirikkaiden polttoaineiden yleistyessä energiamarkkinoilla.The currently-used sources of biomass are limited so new ones are required in order to
meet the European Union target and to satisfy the constantly-increasing demand for
energy. This is why energy recovery from residues or waste derived fuels has been given
considerable attention over recent years.
The residues generated during the production of biofuels for transportation are often the
main stream from the production plant. Proper allocation of the residues could
significantly improve the sustainability of the production process resulting in high
greenhouse gas emission savings and improvement in their profitability. Energy recovery
could be one application, among others, for the residues.
The objective of this study was to investigate the combustion behaviour of four residues
from the production of biofuels for transportation. The residues of interest were: rapeseed
cake, palm kernel cake, dried distillers’ grains with solubles, and fermented sewage
sludge. A wide range of methods of laboratory to semi-industrial scale was applied in
order to define the main challenges related to the fluidized bed combustion of these
residues.
All residues were characterized by means of laboratory methods. The residues differ
substantially in their composition compared to more traditional biomass fuels. Their
common property is a high concentration of phosphorus. Until recently, phosphorus was
considered a negligible element for ash chemistry due to its low concentrations.
Rapeseed cake was further studied, as an example of phosphorus-rich fuel, during benchscale
bubbling fluidized bed (BFB) and semi-industrial scale circulating fluidized bed (CFB)
combustion experiments. Rapeseed cake, with phosphorus and alkali metals dominating
its ash chemistry, led to defluidization at approximately 800 C. Bed sintering during
fluidized bed combustion of pure rapeseed cake followed a non-reactive mechanism. This
mechanism is controlled by the stickiness of fuel-derived ash particles. Entrained fine
rapeseed cake ash particles also aggravated deposit formation. In order to improve the
problematic behaviour two strategies were used: co-combustion and the use of
limestone. Three different base fuels were used: bark, wood, and coal.
Co-firing of rapeseed cake with a minimum of 60 wt% of bark in a bench-scale BFB reactor
increased the defluidization temperatures compared to the pure rapeseed cake case. This
was correlated with the increase of the Ca/P molar, which increased with a higher
proportion of bark in the fuel mixture. During co-firing with wood in a semi-industrial
scale CFB combustor, the addition of limestone was found to be necessary in order to
improve the bed sintering tendency of the fuel mixture.
Co-firing of rapeseed cake with coal in a semi-industrial CFB combustor did not show any
significant operational problems. Therefore co-combustion with coal is considered to be
one of the strategies to improve combustion of phosphorus-rich biomass.
The experimental work in this study revealed that phosphorus has a role during
combustion which cannot be neglected when phosphorus-rich fuels are entering the
energy market. Challenges during fluidized bed combustion of the residues were defined
and countermeasures were investigated.ei tietoa saavutettavuudest
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