1,721,036 research outputs found

    Is mood associated with perception of recovery? Preoperative depression versus postoperative delirium after cardiac surgery

    No full text
    The author alone is responsible for the Invited Commentary, which does not necessarily reflect the policy of the Journal

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Get PDF
    The 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

    Get PDF
    “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

    Get PDF
    We 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

    Dispelling the Myths Behind First-author Citation Counts

    Get PDF
    We 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

    Author Index

    No full text
    Nao informado

    Esialtistavan raajaiskemian aivoja suojaavat vaikutukset sydän- ja aorttakirurgiassa : Kokeellinen tutkimus porsailla

    No full text
    AbstractOpen aortic arch surgery almost always requires a bloodless operating field which necessitates the use of hypothermic circulatory arrest. Hypothermic circulatory arrest is a technique where the core temperature of a patient is lowered so that the systemic blood circulation can be stopped momentarily. This can cause unwanted damage to the brain. The risk for neurological impairment is at its highest when corrective surgery has to be performed in emergency situations. This highlights the need for additional neuroprotective methods. Our research group has used a porcine model described in this thesis for about 12 years in various setups to study many neuroprotective hypotheses. We have tested and researched surgical and CPB strategies that could be useful in a HCA and aortic arch reconstruction setting. In this thesis we have combined both chronic surviving animal data with acute experiments and aim to shed light on the mechanisms and efficacy of RIPC as neuroprotective method. In our experimental model, RIPC provided a mitigation of inflammatory response and cerebral injury after prolonged HCA. In general, the collected data showed homogeneity as similar biochemical results were seen in study I and II. Also interestingly, study III and IV possibly shed some light as to the mechanisms of the neuroprotective effect seen in Study II. These results seem to corroborate each other in a logical way. In study I which was acute experiment we saw faster EEG recovery rates in the intervention group. Additionally we recorded beneficial biochemical changes from samples that were collected from the brain. In our chronic study, were the animals were followed for a 7 day period after hypothermic circulatory arrest, we saw a statistically significant neuroprotective effect of remote ischemic preconditioning. In studies III and IV we attempted to shed light on the mechanisms. Study III revealed that an altered oxygen usage profile during hypothermic circulatory arrest and recovery phase might have a role in the neuroprotection. In study IV we saw a reduced microcirculatory leukocyte accumulation in cerebrocortical vessels was noted using an intravital microscope. The intravital microscope also provided results that indicated a difference in the redox state of the mitochondria via NAD+/NADH autofluorescence measurements. TiivistelmäSydän- ja aorttakirurgiassa tarvitaan jossain tilanteissa täysin veretöntä leikkausaluetta. Verettömän leikkausalueen saavuttamiseksi joudutaan joskus turvautumaan potilaan elimistön jäähdytyksen jälkeiseen verenkierron pysäytykseen. Tämän menetelmän haittana on kuitenki aivokudokselle aiheutuva hapenpuute ja tästä mahdollisesti seuraava vaurioituminen. Vaurioitumisen riski on korkeimillaan erityisesti päivystyksellisissä tilanteissa. Tämän tutkimuksen tavoitteena on ollut selvittää, onko esialtistavalla raajaiskemialla kykyä suojata aivokudosta hapenpuutostilanteissa. Tutkimusryhmämme on viimeisen 12 vuoden aikana tutkinut sianporsailla eri keinoja, joilla voitaisiin parantaa aivojen suojausta sydän- ja aorttakirurgian aikana. Esialtistava raajaiskemia toteutetaan kiristämällä mansetti eläimen oikean takajalan ympärille. Tämän jälkeen mansetti täytetään viiden minuutin välein neljästi. Täyttökertojen välissä pidettään viiden minuutin tauko, jolloin mansetti on avatuna ja jalan verenkierto palautuu normaaliksi. Ensimmäisessä tutkimuksessamme totesimme, että esialtistava raajiskemia vaikuttaa aivojen sähkökäyrän toipumista nopeuttavasti. Toisessa tutkimuksessamme seurasimme koe-eläimiä seitsemän päivän ajan kokeen jälkeen. Tämän tutkimuksen yhteydessä toteutessa aivokudoksen mikroskooppiananalyysissä havaitsimme, että raajaiskemia vaikutti suojaavan aivokudosta hapenpuutteen aiheuttamilta aivovaurioilta. Kolmanessa tutkimuksessa selvitimme, että raajaiskemia vaikuttaa aivojen happipitoisuuteen sekä verenkierron pysäytyksen aikana että toipumisvaiheessa. Viimeisessä tutkimuksessa kuvasimme aivojen pintaverisuonia mikroskoopilla. Seurasimme kokeessa valkosolujen käyttäytymistä aivokudoksessa käyttäen fluoresoivia lääkeaineita. Havaitsimme, että raajaiskemiaryhmässä valkosoluja oli aivokudoksen pintaverisuonissa merkittävästi vähemmän. Lisäksi samalla menetelmällä tutkimme sitruunahappokiertoon osallistuvan NAD+/NADH parin suhteita autofluoresenssi ilmiöllä. Autofluorensenssi tutkimuksen tulokset viittaavat siihen, että mitokondrioiden hapetus/pelkistys kyky oli parempi raajaiskemia ryhmässä. Kokeissamme esialtistava raajaiskemia vähensi tulehdussolujen määrää aivokudoksessa sekä vähensi aivovauriota hapenpuutteen jälkeen. Academic dissertation to be presented with the assent of the Doctoral Training Committee of Health and Biosciences of the University of Oulu for public defence in Auditorium 1 of Oulu University Hospital, on 7 June 2013, at 12 noonAbstract Open aortic arch surgery almost always requires a bloodless operating field which necessitates the use of hypothermic circulatory arrest. Hypothermic circulatory arrest is a technique where the core temperature of a patient is lowered so that the systemic blood circulation can be stopped momentarily. This can cause unwanted damage to the brain. The risk for neurological impairment is at its highest when corrective surgery has to be performed in emergency situations. This highlights the need for additional neuroprotective methods. Our research group has used a porcine model described in this thesis for about 12 years in various setups to study many neuroprotective hypotheses. We have tested and researched surgical and CPB strategies that could be useful in a HCA and aortic arch reconstruction setting. In this thesis we have combined both chronic surviving animal data with acute experiments and aim to shed light on the mechanisms and efficacy of RIPC as neuroprotective method. In our experimental model, RIPC provided a mitigation of inflammatory response and cerebral injury after prolonged HCA. In general, the collected data showed homogeneity as similar biochemical results were seen in study I and II. Also interestingly, study III and IV possibly shed some light as to the mechanisms of the neuroprotective effect seen in Study II. These results seem to corroborate each other in a logical way. In study I which was acute experiment we saw faster EEG recovery rates in the intervention group. Additionally we recorded beneficial biochemical changes from samples that were collected from the brain. In our chronic study, were the animals were followed for a 7 day period after hypothermic circulatory arrest, we saw a statistically significant neuroprotective effect of remote ischemic preconditioning. In studies III and IV we attempted to shed light on the mechanisms. Study III revealed that an altered oxygen usage profile during hypothermic circulatory arrest and recovery phase might have a role in the neuroprotection. In study IV we saw a reduced microcirculatory leukocyte accumulation in cerebrocortical vessels was noted using an intravital microscope. The intravital microscope also provided results that indicated a difference in the redox state of the mitochondria via NAD+/NADH autofluorescence measurements.Tiivistelmä Sydän- ja aorttakirurgiassa tarvitaan jossain tilanteissa täysin veretöntä leikkausaluetta. Verettömän leikkausalueen saavuttamiseksi joudutaan joskus turvautumaan potilaan elimistön jäähdytyksen jälkeiseen verenkierron pysäytykseen. Tämän menetelmän haittana on kuitenki aivokudokselle aiheutuva hapenpuute ja tästä mahdollisesti seuraava vaurioituminen. Vaurioitumisen riski on korkeimillaan erityisesti päivystyksellisissä tilanteissa. Tämän tutkimuksen tavoitteena on ollut selvittää, onko esialtistavalla raajaiskemialla kykyä suojata aivokudosta hapenpuutostilanteissa. Tutkimusryhmämme on viimeisen 12 vuoden aikana tutkinut sianporsailla eri keinoja, joilla voitaisiin parantaa aivojen suojausta sydän- ja aorttakirurgian aikana. Esialtistava raajaiskemia toteutetaan kiristämällä mansetti eläimen oikean takajalan ympärille. Tämän jälkeen mansetti täytetään viiden minuutin välein neljästi. Täyttökertojen välissä pidettään viiden minuutin tauko, jolloin mansetti on avatuna ja jalan verenkierto palautuu normaaliksi. Ensimmäisessä tutkimuksessamme totesimme, että esialtistava raajiskemia vaikuttaa aivojen sähkökäyrän toipumista nopeuttavasti. Toisessa tutkimuksessamme seurasimme koe-eläimiä seitsemän päivän ajan kokeen jälkeen. Tämän tutkimuksen yhteydessä toteutessa aivokudoksen mikroskooppiananalyysissä havaitsimme, että raajaiskemia vaikutti suojaavan aivokudosta hapenpuutteen aiheuttamilta aivovaurioilta. Kolmanessa tutkimuksessa selvitimme, että raajaiskemia vaikuttaa aivojen happipitoisuuteen sekä verenkierron pysäytyksen aikana että toipumisvaiheessa. Viimeisessä tutkimuksessa kuvasimme aivojen pintaverisuonia mikroskoopilla. Seurasimme kokeessa valkosolujen käyttäytymistä aivokudoksessa käyttäen fluoresoivia lääkeaineita. Havaitsimme, että raajaiskemiaryhmässä valkosoluja oli aivokudoksen pintaverisuonissa merkittävästi vähemmän. Lisäksi samalla menetelmällä tutkimme sitruunahappokiertoon osallistuvan NAD+/NADH parin suhteita autofluoresenssi ilmiöllä. Autofluorensenssi tutkimuksen tulokset viittaavat siihen, että mitokondrioiden hapetus/pelkistys kyky oli parempi raajaiskemia ryhmässä. Kokeissamme esialtistava raajaiskemia vähensi tulehdussolujen määrää aivokudoksessa sekä vähensi aivovauriota hapenpuutteen jälkeen

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

    No full text
    We 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
    corecore