101 research outputs found

    Loneliness Across the Life Span

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    Most people have experienced loneliness and have been able to overcome it to reconnect with other people. In the current review, we provide a life-span perspective on one component of the evolutionary theory of loneliness—a component we refer to as the reaffiliation motive (RAM). The RAM represents the motivation to reconnect with others that is triggered by perceived social isolation. Loneliness is often a transient experience because the RAM leads to reconnection, but sometimes this motivation can fail, leading to prolonged loneliness. We review evidence of how aspects of the RAM change across development and how these aspects can fail for different reasons across the life span. We conclude with a discussion of age-appropriate interventions that may help to alleviate prolonged lonelines

    Catch comparison of pulse trawls vessels and a tickler chain beam trawler

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    Comparative fishing trials were conducted in May 2011 (week 19) on commercial beam trawlers fishing with conventional tickler chain beam trawls (on MFV GO4), pulse wings made by HFK-Engineering of Baarn, the Netherlands (MFV TX36), and pulse trawls produced by the DELMECO-Group of Goes, the Netherlands (version used on MFV TX68). The three vessels fished side-by-side as much as possible. Landings and discards of these vessels were monitored. Special emphasis was given on cod and whiting, that were dissected to study possible spinal damage. Result for TX36 and TX68 are expressed in terms of percentages of GO4. The pulse characteristics were as follows: TX36: voltage 45 V0 to peak, pulse frequency: 45 Hz, pulse duration 380 μs; electric power on single gear: 7.0 kW; TX68: voltage 50 V0 to peak, pulse frequency: 50 Hz, pulse duration 220 μs; electric power on single gear: 8.5 kW. The fuel consumption recorded over the whole week was considerably lower for the pulse trawls, i.e. on TX36 (40%) and on TX68 (54%), than for the tickler chain beam trawls used on the GO4. The net earnings (taken as gross earnings minus fuel costs) for the TX36 were almost twice as large at 186%, and for the TX68 also considerably higher at 155%. The vessels with pulse trawls caught fewer (65-69%) target species, but also less (30-50%) immature and non-target fish ('discards'), and benthic species (48-73%) than the vessel with tickler chains on these fishing grounds and in this period. The pulse gears caught fewer (19-42%) kg per hour cod than the tickler chain beam trawls, but the catches of cod on all three vessels were very small. For plaice and dab these differences were statistically proven, for brill, turbot and cod this was not the case. There was no marked difference between both pulse trawl vessels in total landings. The TX68 caught less marketable sole, but not significantly less undersized sole than the GO4. The TX36 caught less undersized sole, but here the difference in marketable fish was not significant. Catches of brill and turbot were so small that no statistically substantiated conclusion could be drawn. Only for undersized turbot the TX36 caught less. For whiting we found a demonstrable reduction in both marketable and undersized fish in both pulse fishing vessels. The TX36 caught less whiting in number per hour. The CPUEs found from the auction data and the sampled hauls correlated reasonably well for the most abundant species, such as plaice and sole. However, for less abundant species the results did not match very well, and care should be taken to increase the sampling rate in future comparative fishing studies. Spinal fracture in cod occurred under pulse stimulation but to a limited extent in both marketable and undersized fish. There is an indication that this happens slightly more on TX68 (11%) than on TX36 (7%). Whiting hardly seems to suffer any damage

    Vangstvergelijking tussen pulskorschepen en een conventioneel boomkor-vaartuig

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    In mei 2011 (week 19) werd een vergelijkende visserij uitgevoerd aan boord van de kotters GO4 (wekkerboomkorren), TX36 (HFK pulswings), en de toenmalige versie van DELMECO pulskorren gebruikt op de TX68. De schepen visten zoveel mogelijk giek-aan-giek in hetzelfde gebied. Tevens werd aandacht besteed aan mogelijk ruggengraatletsel van kabeljauw en wijting. De pulskarakteristieken waren als volgt: TX36: voltage 45 V0 tot piek, pulsfrequentie: 45 Hz, pulsduur 380 µs; elektrisch vermogen op één tuig: 7.0 kW; TX68: voltage 50 V0 tot piek, pulsfrequentie: 50 Hz, pulsduur 220 µs; elektrisch vermogen op één tuig: 8.5 kW. Het brandstofverbruik over de gehele visweek was aanzienlijk minder voor de TX36 (40%) en de TX68 (54%), dan de GO4. Voor de netto besomming (= bruto besomming – gasoliekosten) vonden we zelfs bijna een verdubbeling in efficiëntie voor de TX36 (186%), en een ruime toename voor de TX68 (155%). De schepen met pulstuigen vingen minder (65-69%) van de belangrijkste doelsoorten dan het schip met wekkerkorren op dit bestek en in deze periode, maar ook minder (30-50%) ondermaatse en niet-vermarktbare soorten vis (EN: ‘discards’) en minder bodemdieren (48-73%). De pulstuigen bleken minder (19-42%) maatse kabeljauw in kg/u te vangen dan de wekkerkor, maar de vangsten van deze soort waren voor alle schepen gering. Voor schol en schar waren de verschillen statistisch aantoonbaar, voor griet, tarbot wijting en kabeljauw niet. De pulskorschepen onderling lieten geen duidelijke verschillen in totale aanlanding zien. De TX68 bleek minder maatse tong te vangen, maar niet duidelijk minder ondermaatse tong dan de GO4. Bij de TX36 was het andersom: hier werd minder ondermaatse tong gevangen, maar het verschil in maatse vis was niet duidelijk. De vangsten van griet en tarbot waren zo gering, dat doorgaans geen statistisch onderbouwde conclusie kon worden getrokken. Alleen van ondermaatse tarbot ving de TX36 significant minder. Voor wijting vonden we wel een aanwijsbare vermindering van zowel maatse als ondermaatse vis voor de pulskorschepen. In aantal/u bleek de TX36 ook minder te vangen. Er was een redelijke overeenkomst tussen het vangstsucces (vangst per eenheid van inspanning of CPUE) berekend uit de afslaggegevens en het vangstsucces berekend uit de bemonsterde trekken voor soorten die talrijk voorkomen, zoals schol en tong. Voor minder voorkomende soorten, was de correlatie minder sterk. Dit zou voorkomen kunnen worden door meer en grotere monsters te nemen in toekomstige vangstvergelijkingen. Kabeljauw (ondermaatse en maatse vis) ondervond in de pulstuigen in beperkte mate breuk van de ruggengraat. Er is een indicatie, dat dit voor de TX68 iets meer (11%) optrad dan voor de TX36 (7%). Wijting leek nauwelijks schade te ondervinden

    Catch comparison of pulse trawls vessels and a tickler chain beam trawler

    Get PDF
    Comparative fishing trials were conducted in May 2011 (week 19) on commercial beam trawlers fishing with conventional tickler chain beam trawls (on MFV GO4), pulse wings made by HFK-Engineering of Baarn, the Netherlands (MFV TX36), and pulse trawls produced by the DELMECO-Group of Goes, the Netherlands (version used on MFV TX68). The three vessels fished side-by-side as much as possible. Landings and discards of these vessels were monitored. Special emphasis was given on cod and whiting, that were dissected to study possible spinal damage. Result for TX36 and TX68 are expressed in terms of percentages of GO4. The pulse characteristics were as follows: TX36: voltage 45 V0 to peak, pulse frequency: 45 Hz, pulse duration 380 μs; electric power on single gear: 7.0 kW; TX68: voltage 50 V0 to peak, pulse frequency: 50 Hz, pulse duration 220 μs; electric power on single gear: 8.5 kW. The fuel consumption recorded over the whole week was considerably lower for the pulse trawls, i.e. on TX36 (40%) and on TX68 (54%), than for the tickler chain beam trawls used on the GO4. The net earnings (taken as gross earnings minus fuel costs) for the TX36 were almost twice as large at 186%, and for the TX68 also considerably higher at 155%. The vessels with pulse trawls caught fewer (65-69%) target species, but also less (30-50%) immature and non-target fish ('discards'), and benthic species (48-73%) than the vessel with tickler chains on these fishing grounds and in this period. The pulse gears caught fewer (19-42%) kg per hour cod than the tickler chain beam trawls, but the catches of cod on all three vessels were very small. For plaice and dab these differences were statistically proven, for brill, turbot and cod this was not the case. There was no marked difference between both pulse trawl vessels in total landings. The TX68 caught less marketable sole, but not significantly less undersized sole than the GO4. The TX36 caught less undersized sole, but here the difference in marketable fish was not significant. Catches of brill and turbot were so small that no statistically substantiated conclusion could be drawn. Only for undersized turbot the TX36 caught less. For whiting we found a demonstrable reduction in both marketable and undersized fish in both pulse fishing vessels. The TX36 caught less whiting in number per hour. The CPUEs found from the auction data and the sampled hauls correlated reasonably well for the most abundant species, such as plaice and sole. However, for less abundant species the results did not match very well, and care should be taken to increase the sampling rate in future comparative fishing studies. Spinal fracture in cod occurred under pulse stimulation but to a limited extent in both marketable and undersized fish. There is an indication that this happens slightly more on TX68 (11%) than on TX36 (7%). Whiting hardly seems to suffer any damage

    Vangstvergelijking tussen pulskorschepen en een conventioneel boomkor-vaartuig

    Get PDF
    In mei 2011 (week 19) werd een vergelijkende visserij uitgevoerd aan boord van de kotters GO4 (wekkerboomkorren), TX36 (HFK pulswings), en de toenmalige versie van DELMECO pulskorren gebruikt op de TX68. De schepen visten zoveel mogelijk giek-aan-giek in hetzelfde gebied. Tevens werd aandacht besteed aan mogelijk ruggengraatletsel van kabeljauw en wijting. De pulskarakteristieken waren als volgt: TX36: voltage 45 V0 tot piek, pulsfrequentie: 45 Hz, pulsduur 380 µs; elektrisch vermogen op één tuig: 7.0 kW; TX68: voltage 50 V0 tot piek, pulsfrequentie: 50 Hz, pulsduur 220 µs; elektrisch vermogen op één tuig: 8.5 kW. Het brandstofverbruik over de gehele visweek was aanzienlijk minder voor de TX36 (40%) en de TX68 (54%), dan de GO4. Voor de netto besomming (= bruto besomming – gasoliekosten) vonden we zelfs bijna een verdubbeling in efficiëntie voor de TX36 (186%), en een ruime toename voor de TX68 (155%). De schepen met pulstuigen vingen minder (65-69%) van de belangrijkste doelsoorten dan het schip met wekkerkorren op dit bestek en in deze periode, maar ook minder (30-50%) ondermaatse en niet-vermarktbare soorten vis (EN: ‘discards’) en minder bodemdieren (48-73%). De pulstuigen bleken minder (19-42%) maatse kabeljauw in kg/u te vangen dan de wekkerkor, maar de vangsten van deze soort waren voor alle schepen gering. Voor schol en schar waren de verschillen statistisch aantoonbaar, voor griet, tarbot wijting en kabeljauw niet. De pulskorschepen onderling lieten geen duidelijke verschillen in totale aanlanding zien. De TX68 bleek minder maatse tong te vangen, maar niet duidelijk minder ondermaatse tong dan de GO4. Bij de TX36 was het andersom: hier werd minder ondermaatse tong gevangen, maar het verschil in maatse vis was niet duidelijk. De vangsten van griet en tarbot waren zo gering, dat doorgaans geen statistisch onderbouwde conclusie kon worden getrokken. Alleen van ondermaatse tarbot ving de TX36 significant minder. Voor wijting vonden we wel een aanwijsbare vermindering van zowel maatse als ondermaatse vis voor de pulskorschepen. In aantal/u bleek de TX36 ook minder te vangen. Er was een redelijke overeenkomst tussen het vangstsucces (vangst per eenheid van inspanning of CPUE) berekend uit de afslaggegevens en het vangstsucces berekend uit de bemonsterde trekken voor soorten die talrijk voorkomen, zoals schol en tong. Voor minder voorkomende soorten, was de correlatie minder sterk. Dit zou voorkomen kunnen worden door meer en grotere monsters te nemen in toekomstige vangstvergelijkingen. Kabeljauw (ondermaatse en maatse vis) ondervond in de pulstuigen in beperkte mate breuk van de ruggengraat. Er is een indicatie, dat dit voor de TX68 iets meer (11%) optrad dan voor de TX36 (7%). Wijting leek nauwelijks schade te ondervinden

    Investigating hyper-vigilance for social threat of lonely children

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    The hypothesis that lonely children show hypervigilance for social threat was examined in a series of three studies that employed different methods including advanced eye-tracking technology. Hypervigilance for social threat was operationalized as hostility to ambiguously motivated social exclusion in a variation of the hostile attribution paradigm (Study 1), scores on the Children’s Rejection-Sensitivity Questionnaire (Study 2), and visual attention to socially rejecting stimuli (Study 3). The participants were 185 children (11 years-7 months to 12 years-6 months), 248 children (9 years-4 months to 11 years-8 months) and 140 children (8 years-10 months to 12 years-10 months) in the three studies, respectively. Regression analyses showed that, with depressive symptoms covaried, there were quadratic relations between loneliness and these different measures of hypervigilance to social threat. As hypothesized, only children in the upper range of loneliness demonstrated elevated hostility to ambiguously motivated social exclusion, higher scores on the rejection sensitivity questionnaire, and disengagement difficulties when viewing socially rejecting stimuli. We found that very lonely children are hypersensitive to social threat

    Adolescent Loneliness and Social Skills:Agreement and Discrepancies Between Self-, Meta-, and Peer-Evaluations

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    Contains fulltext : 160961.pdf (publisher's version ) (Open Access)Lonely adolescents report that they have poor social skills, but it is unknown whether this is due to an accurate perception of a social skills deficit, or a biased negative perception. This is an important distinction, as actual social skills deficits require different treatments than biased negative perceptions. In this study, we compared self-reported social skills evaluations with peer-reported social skills and meta-evaluations of social skills (i.e., adolescents' perceptions of how they believe their classmates evaluate them). Based on the social skills view, we expected negative relations between loneliness and these three forms of social skills evaluations. Based on the bias view, we expected lonely adolescents to have more negative self- and meta-evaluations compared to peer-evaluations of social skills. Participants were 1342 adolescents (48.64 % male, M age = 13.95, SD = .54). All classmates rated each other in a round-robin design to obtain peer-evaluations. Self- and meta-evaluations were obtained using self-reports. Data were analyzed using polynomial regression analyses and response surface modeling. The results indicated that, when self-, peer- and meta-evaluations were similar, a greater sense of loneliness was related to poorer social skills. Loneliness was also related to larger discrepancies between self- and peer-evaluations of loneliness, but not related to the direction of these discrepancies. Thus, for some lonely adolescents, loneliness may be related to an actual social skills deficit, whereas for others a biased negative perception of one's own social skills or a mismatch with the environment may be related to their loneliness. This implies that different mechanisms may underlie loneliness, which has implications for interventions.11 p

    Mouse Protocadherin-1 gene expression is regulated by cigarette smoke exposure in vivo

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    Protocadherin-1 (PCDH1) is a novel susceptibility gene for airway hyperresponsiveness, first identified in families exposed to cigarette smoke and is expressed in bronchial epithelial cells. Here, we asked how mouse Pcdh1 expression is regulated in lung structural cells in vivo under physiological conditions, and in both short-term cigarette smoke exposure models characterized by airway inflammation and hyperresponsiveness and chronic cigarette smoke exposure models. Pcdh1 gene-structure was investigated by Rapid Amplification of cDNA Ends. Pcdh1 mRNA and protein expression was investigated by qRT-PCR, western blotting using isoform-specific antibodies. We observed 87% conservation of the Pcdh1 nucleotide sequence, and 96% conservation of the Pcdh1 protein sequence between men and mice. We identified a novel Pcdh1 isoform encoding only the intracellular signalling motifs. Cigarette smoke exposure for 4 consecutive days markedly reduced Pcdh1 mRNA expression in lung tissue (3 to 4-fold), while neutrophilia and airway hyperresponsiveness was induced. Moreover, Pcdh1 mRNA expression in lung tissue was reduced already 6 hours after an acute cigarette-smoke exposure in mice. Chronic exposure to cigarette smoke induced loss of Pcdh1 protein in lung tissue after 2 months, while Pcdh1 protein levels were no longer reduced after 9 months of cigarette smoke exposure. We conclude that Pcdh1 is highly homologous to human PCDH1, encodes two transmembrane proteins and one intracellular protein, and is regulated by cigarette smoke exposure in vivo

    Trajectories of Early Adolescent Loneliness: Implications for Physical Health and Sleep

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    The current study examines the relationship between prolonged loneliness, physical health, and sleep among young adolescents (10–13 years; N = 1214; 53% girls). Loneliness was measured at 10, 12 and 13 years of age along with parent-reported health and sleep outcomes. Using growth mixture modelling, 6 distinct trajectories were identified: ‘low increasing to high loneliness’ (n = 23, 2%), ‘high reducing loneliness’ (n = 28, 3%), ‘medium stable loneliness’ (n = 60, 5%), ‘medium reducing loneliness’ (n = 185, 15%), ‘low increasing to medium loneliness’ (n = 165, 14%), and ‘low stable loneliness’ (n = 743, 61%). Further analyses found non-significant differences between the loneliness trajectories and parent-report health and sleep outcomes including visits to health professionals, perceived general health, and sleep quality. The current study offers an important contribution to the literature on loneliness and health. Results show that the relationship may not be evident in early adolescence when parent reports of children’s health are used. The current study highlights the importance of informant choice when reporting health. The implications of the findings for future empirical work are discussed
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