282 research outputs found
Product Recommendations in E-commerce Systems using Content-based Clustering and Collaborative Filtering
In this report we take a new approach to product recommendation. We investigate the the possibility of using a hybrid recommender consisting of contentbased clustering and connections between clusters using collaborative filtering to make good product recommendations. The algorithm is tested on real product and purchase data from two different companies - a big online book store and a smaller online clothing store. It is evaluated both for functionality as a backfiller to other algorithms and as a strong individual algorithm. The evaluation mainly looks at the number of purchases as metric but also uses accuracy and recall as evaluation metrics. The algorithm shows some promise for using it as an individual algorithm
MÄngfaldens enfald - En diskursanalys med utgÄngspunkt i city branding av mÄngfaldsbegreppet i Malmö stads kommunikation
City branding consists of the complicated task to communicate an entire city as one single brand. The city brand must satisfy the inhabitantsâneed to feel a sense of belonging without risking excluding outsiders. The choice of words of value must reflect the populationâs characteristics, variations and capacities and at the same time be communicated consistently and coherently to stakeholders. Malmö has chosen to integrate the word "diversity" in their municipality slogan - a word that in itself might be interpreted in various ways. The paper centers around a discourse analysis of the word âdiversityâ and what meaning the word âdiversityâ acquires in Malmöâs communication and how this co-relates to city branding. The analysis showed that the word âdiversityâ was given different types of meaning depending on the context. In abstract contexts, in a discourse of success, the word had including and positive connotations. In substantial, concrete contexts â in a discourse of problems â the word âdiversityâ came to be excluding and restricted to embody solely ethnic diversity. The analysis also found that the word âdiversityâ can be interpreted either as an actuality or as something that must be accomplished. Therefore might the word âdiversityâ be the closest we can get to unite the contradicting ground principles in city branding: to create a brand that must be realistic and representative as well as desirable and attractive. The work regarding this examination paper has been divided evenly between the two co-writers.City branding bestĂ„r av den tunga uppgiften att marknadsföra en hel stad under ett enda varumĂ€rke. StadsvarumĂ€rket mĂ„ste tillfredsstĂ€lla invĂ„narnas behov av samhörighet utan att exkludera utomstĂ„ende. Valet av vĂ€rdeord mĂ„ste Ă„terspegla populationens variationer och egenskaper samtidigt som det mĂ„ste kommuniceras konsekvent och enhetligt till intressenter. Malmö stad har valt att i sin kommunslogan integrera begreppet âmĂ„ngfaldâ - ett begrepp som i sig sjĂ€lvt inbegriper ett omfattande tolkningsutrymme. Uppsatsen centreras kring en diskursanalys av mĂ„ngfaldsbegreppet som söker svar pĂ„ frĂ„gorna om vilken betydelse begreppet mĂ„ngfald ges i Malmö stads kommunikation och hur det korrelerar med city branding. Analysen fann att mĂ„ngfaldsbegreppet gavs olika innebörd i abstrakta respektive konkreta kontexter: dĂ€r begreppet fungerade som inkluderande och positivt i en abstrakt framgĂ„ngsdiskurs men exkluderande och begrĂ€nsat till etnisk mĂ„ngfald i en konkret problemdiskurs. Vidare fann analysen att mĂ„ngfald kan tolkas antingen som nĂ„got som âbara Ă€râ eller som nĂ„got som bör uppnĂ„s. MĂ„ngfaldsbegreppet blir dĂ€rför mĂ„hĂ€nda det nĂ€rmaste man kan komma att förena de motsĂ€gelsefulla grundprinciperna i city branding: att ett varumĂ€rke som mĂ„ste vara representativt och verkligt samtidigt som det mĂ„ste vara önskvĂ€rt och tydligt. Arbetet kring detta examensarbete har till lika stora delar utförts av bĂ„da författarna
Neuronal Processing of Complex Mixtures Establishes a Unique Odor Representation in the Moth Antennal Lobe
Animals typically perceive natural odor cues in their olfactory environment as a complex mixture of chemically diverse components. In insects, the initial representation of an odor mixture occurs in the first olfactory center of the brain, the antennal lobe (AL). The contribution of single neurons to the processing of complex mixtures in insects, and in particular moths, is still largely unknown. Using a novel multicomponent stimulus system to equilibrate component and mixture concentrations according to vapor pressure, we performed intracellular recordings of projection and interneurons in an attempt to quantitatively characterize mixture representation and integration properties of single AL neurons in the moth. We found that the fine spatiotemporal representation of 2â7 component mixtures among single neurons in the AL revealed a highly combinatorial, non-linear process for coding host mixtures presumably shaped by the AL network: 82% of mixture responding projection neurons and local interneurons showed non-linear spike frequencies in response to a defined host odor mixture, exhibiting an array of interactions including suppression, hypoadditivity, and synergism. Our results indicate that odor mixtures are represented by each cell as a unique combinatorial representation, and there is no general rule by which the network computes the mixture in comparison to single components. On the single neuron level, we show that those differences manifest in a variety of parameters, including the spatial location, frequency, latency, and temporal pattern of the response kinetics
Long working hours, anthropometry, lung function, blood pressure and blood-based biomarkers : cross-sectional findings from the CONSTANCES study
Background Although long working hours have been shown to be associated with the onset of cardiometabolic diseases, the clinical risk factor profile associated with long working hours remains unclear. We compared the clinical risk profile between people who worked long hours and those who reported being never exposed to long hours. Methods A cross-sectional study in 22 health screening centres in France was based on a random population-based sample of 75 709 participants aged 18-69 at study inception in 2012-2016 (the CONSTANCES study). The data included survey responses on working hours (never, former or current exposure to long working hours), covariates and standardised biomedical examinations including anthropometry, lung function, blood pressure and standard blood-based biomarkers. Results Among men, long working hours were associated with higher anthropometric markers (Body Mass Index, waist circumference and waist:hip ratio), adverse lipid levels, higher glucose, creatinine, white blood cells and higher alanine transaminase (adjusted mean differences in the standardised scale between the exposed and unexposed 0.02-0.12). The largest differences were found for Body Mass Index and waist circumference. A dose-response pattern with increasing years of working long hours was found for anthropometric markers, total cholesterol, glucose and gamma-glutamyltransferase. Among women, long working hours were associated with Body Mass Index and white blood cells. Conclusion In this study, men who worked long hours had slightly worse cardiometabolic and inflammatory profile than those who did not work long hours, especially with regard to anthropometric markers. In women, the corresponding associations were weak or absent.Peer reviewe
Sommarmellangrödors ogrÀsbekÀmpande egenskaper - resultat frÄn tvÄ fÀltförsök 2016
Under 2016 genomfördes tvĂ„ fĂ€ltförsök med fokus pĂ„ olika sommarmellangrödors ogrĂ€sbekĂ€mpande egenskaper samt dess biomassaproduktion. Ett av försöken var placerat pĂ„ Norra Ă
sum vid Kristianstad i SkÄne och det andra pÄ Lilla Böslid vid Laholm i Halland.
De sommarmellangrödor som hade bĂ€st ogrĂ€skonkurrerande egenskaper pĂ„ de bĂ„da försöksplatserna var oljerĂ€ttika, facelia och bovete, medan sudangrĂ€set var sĂ€mst pĂ„ att konkurrera med ogrĂ€set. PĂ„ Norra Ă
sum hade Àven hampa samt hampa i samodling med luddvicker lika bra ogrÀskonkurrerande effekt som oljerÀttika, facelia och bovete.
HĂ€lften av parcellerna gödslades med kvĂ€ve pĂ„ bĂ„da försöksplatserna. PĂ„ Norra Ă
sum var det generellt fler ogrĂ€s i de gödslade leden. FörhĂ„llandet var det motsatta pĂ„ Lilla Böslid dĂ€r ogrĂ€sfloran dominerades av Ă„kerspergel. I de gödslade leden pĂ„ Norra Ă
sum fanns det ett svagt samband mellan ogrÀsets torrvikt och sommarmellangrödornas torrvikt. Ju större sommarmellangrödans biomassa var desto lÀgre blev ogrÀsvikten.
Sommarmellangrödorna, som alla sĂ„ddes den 20 juli pĂ„ Norra Ă
sum, gav största skörden dÄ de skördades den 13 oktober (85 dagars kulturtid). SudangrÀs i kombination med luddvicker gav dock en större skörd den 7 november (110 dagars kulturtid).
I de gödslade leden pĂ„ Norra Ă
sum med 41 kg ammoniumkvÀve per ha i form av biogödsel (rötrest) gav hampa den signifikant högsta mÀngden biomassa (4,2 ton ts/ha), medan gödslat sudangrÀs resp. bovete gav den lÀgsta biomassan (2,9 ton ts/ha) i mitten av oktober. Gödslad oljerÀttika jÀmfört med ogödslad oljerÀttika ökade skörden 2,3 gÄnger, frÄn 1,4 till 3,3 ton ts/ha. I de ogödslade leden gav hampa i kombination med luddvicker den signifikant högsta skörden (3,8 ton ts/ha).
Slutsatsen frĂ„n försöken under 2016 med sommarmellangrödors ogrĂ€sbekĂ€mpande egenskaper Ă€r följande: OljerĂ€ttika, facelia, bovete och hampa samt hampa i kombination med luddvicker har förutsĂ€ttningar att konkurrera bra mot ogrĂ€s pĂ„ lĂ€ttare sandjord. Detta under förutsĂ€ttning att mellangrödorna etablerar sig bra och att de har en god tillvĂ€xt under sommaren och hösten. Gödsling av sommarmellangrödorna med ca 40 resp. ca 50 kg kvĂ€ve per ha resulterade generellt i fler ogrĂ€s pĂ„ Norra Ă
sum, och fÀrre pÄ Lilla Böslid dÀr ogrÀsfloran dominerades av Äkerspergel. Detta resultat visar att ytterligare försök med sommarmellangrödors ogrÀskonkurrerande egenskaper behöver genomföras för att fastslÄ gödslingens pÄverkan pÄ ogrÀseffekten och mellangrödans biomassaproduktion under olika ÄrsmÄner, markförhÄllanden etc
Influence of ghrelin on the central serotonergic signaling system in mice
AbstractThe central ghrelin signaling system engages key pathways of importance for feeding control, recently shown to include those engaged in anxiety-like behavior in rodents. Here we sought to determine whether ghrelin impacts on the central serotonin system, which has an important role in anxiety. We focused on two brain areas, the amygdala (of importance for the mediation of fear and anxiety) and the dorsal raphe (i.e. the site of origin of major afferent serotonin pathways, including those that project to the amygdala). In these brain areas, we measured serotonergic turnover (using HPLC) and the mRNA expression of a number of serotonin-related genes (using real-time PCR). We found that acute central administration of ghrelin to mice increased the serotonergic turnover in the amygdala. It also increased the mRNA expression of a number of serotonin receptors, both in the amygdala and in the dorsal raphe. Studies in ghrelin receptor (GHS-R1A) knock-out mice showed a decreased mRNA expression of serotonergic receptors in both the amygdala and the dorsal raphe, relative to their wild-type littermates. We conclude that the central serotonin system is a target for ghrelin, providing a candidate neurochemical substrate of importance for ghrelin's effects on mood
Integrating multiple dimensions of ecological stability into a vulnerability framework
Ecological stability encompasses multiple dimensions of functional and compositional responses to environmental change. Though no single stability dimension used in isolation can fully reflect the overall response to environmental change, a common vulnerability assessment that integrates simultaneously across multiple stability components is highly desirable for ecological risk assessment. We develop both functional and compositional counterparts of a novel, integrative metric of overall ecological vulnerability (OEV). We test the framework with data from a modularized experiment replicated in five lakes over two seasons, examining functional and compositional responses to both pulse and press disturbances across three trophic groups. OEV is measured as the area under the curve integrated over the entire observation period, with the curve delimiting the difference between the disturbance treatment and undisturbed parallel controls, expressed either as the log response ratio of biomass (functional OEV) or community dissimilarity index (compositional OEV). Both, functional and compositional OEV correlated negatively with functional and compositional 'resistance', 'temporal stability' and 'final/extent of recovery' following both pulse and press disturbances, though less so with 'resilience' following a pulse disturbance. We also found a positive correlation between functional and compositional OEV, which reveals the potential to also evaluate the intricate linkage between biodiversity and functional change. Our findings demonstrate that OEV comprises a robust framework to: (a) capture simultaneously multiple functional and compositional stability components, and (b) quantify the functional consequences of biodiversity change. Our results provide the basis for an overarching framework for quantifying the overall vulnerability of ecosystems to environmental change, opening new possibilities for ecological risk assessment and management. Synthesis. Ecological stability comprises multiple dimensions that together encapsulate how ecosystems respond to environmental change. Considering these multiple aspects of stability simultaneously often poses a problem in environmental assessments, which frequently require overarching indicators of risk or vulnerability. While an analysis of multiple dimensions allows for deeper exploration of mechanisms, here we develop and test a new univariate indicator that integrates stability aspects under a broad range of disturbance regimes. Using a modularized experiment in Swedish lakes, we show that this integrative measure captures multiple stability dimensions reflecting compositional and functional vulnerability and their relationships between them
Long working hours, anthropometry, lung function, blood pressure and blood-based biomarkers: Cross-sectional findings from the CONSTANCES study
Background Although long working hours have been shown to be associated with the onset of cardiometabolic diseases, the clinical risk factor profile associated with long working hours remains unclear. We compared the clinical risk profile between people who worked long hours and those who reported being never exposed to long hours.Methods A cross-sectional study in 22 health screening centres in France was based on a random population-based sample of 75 709 participants aged 18â69 at study inception in 2012â2016 (the CONSTANCES study). The data included survey responses on working hours (never, former or current exposure to long working hours), covariates and standardised biomedical examinations including anthropometry, lung function, blood pressure and standard blood-based biomarkers.Results Among men, long working hours were associated with higher anthropometric markers (Body Mass Index, waist circumference and waist:hip ratio), adverse lipid levels, higher glucose, creatinine, white blood cells and higher alanine transaminase (adjusted mean differences in the standardised scale between the exposed and unexposed 0.02â0.12). The largest differences were found for Body Mass Index and waist circumference. A doseâresponse pattern with increasing years of working long hours was found for anthropometric markers, total cholesterol, glucose and gamma-glutamyltransferase. Among women, long working hours were associated with Body Mass Index and white blood cells.Conclusion In this study, men who worked long hours had slightly worse cardiometabolic and inflammatory profile than those who did not work long hours, especially with regard to anthropometric markers. In women, the corresponding associations were weak or absent.</div
Identification of nine sequence types of the 16S rRNA genes of Campylobacter jejuni subsp. jejuni isolated from broilers
<p>Abstract</p> <p>Background</p> <p>Campylobacter is the most commonly reported bacterial cause of enteritis in humans in the EU Member States and other industrialized countries. One significant source of infection is broilers and consumption of undercooked broiler meat. <it>Campylobacter jejuni </it>is the <it>Campylobacter </it>sp. predominantly found in infected humans and colonized broilers. Sequence analysis of the 16S rRNA gene is very useful for identification of bacteria to genus and species level. The objectives in this study were to determine the degree of intraspecific variation in the 16S rRNA genes of <it>C. jejuni </it>and <it>C. coli </it>and to determine whether the 16S rRNA sequence types correlated with genotypes generated by PFGE analysis of <it>Sma</it>I restricted genomic DNA of the strains.</p> <p>Methods</p> <p>The 16S rRNA genes of 45 strains of <it>C. jejuni </it>and two <it>C. coli </it>strains isolated from broilers were sequenced and compared with 16S rRNA sequences retrieved from the Ribosomal Database Project or GenBank. The strains were also genotyped by PFGE after digestion with <it>Sma</it>I.</p> <p>Results</p> <p>Sequence analyses of the 16S rRNA genes revealed nine sequence types of the <it>Campylobacter </it>strains and the similarities between the different sequence types were in the range 99.6â99.9%. The number of nucleotide substitutions varied between one and six among the nine 16S rRNA sequence types. One of the nine 16S rRNA sequence profiles was common to 12 of the strains from our study and two of these were identified as <it>Campylobacter coli </it>by PCR/REA. The other 10 strains were identified as <it>Campylobacter jejuni</it>. Five of the nine sequence types were also found among the <it>Campylobacter </it>sequences deposited in GenBank. The three 16S rRNA genes in the analysed strains were identical within each individual strain for all 47 strains.</p> <p>Conclusion</p> <p><it>C. jejuni </it>and <it>C. coli </it>seem to lack polymorphisms in their 16S rRNA gene, but phylogenetic analysis based on 16S rRNA sequences was not always sufficient for differentiation between <it>C. jejuni </it>and <it>C. coli</it>. The strains were grouped in two major clusters according to 16S rRNA, one cluster with only <it>C. jejuni </it>and the other with both <it>C. jejuni </it>and <it>C. coli</it>. Genotyping of the 47 strains by PFGE after digestion with <it>Sma</it>I resulted in 22 subtypes. A potential correlation was found between the <it>Sma</it>I profiles and the 16S rRNA sequences, as a certain <it>Sma</it>I type only appeared in one of the two major phylogenetic groups.</p
Capability in research on cognition and well-being in ageing and retirement
In this chapter, we outline our thoughts on capability in relation to previous and ongoing research projects conducted by the Adult Development and Ageing (ADA-Gero) Research Group located at the Department of Psychology, University of Gothenburg, Sweden. More specifically, we relate our research on cognitive ageing and subjective well-being to the overarching capability framework implemented as a theoretical platform in the AgeCap research consortium
- âŠ