1,699 research outputs found
Three distinct mechanisms generate oxygen free radicals in neurons and contribute to cell death during anoxia and reoxygenation
No full textIschemia is a major cause of brain damage, and patient management is complicated by the paradoxical injury that results from reoxygenation. We have now explored the generation of reactive oxygen species (ROS) in hippocampal and cortical neurons in culture in response to oxygen and glucose deprivation or metabolic inhibition and reoxygenation. Fluorescence microscopy was used to measure the rate of ROS generation using hydroethidine, dicarboxyfluorescein diacetate, or MitoSOX. ROS generation was correlated with changing mitochondrial potential (rhodamine 123), [Ca2+]c (fluo-4, fura-2, or Indo-1), or ATP consumption, indicated by increased [Mg2+]c. We found that three distinct mechanisms contribute to neuronal injury by generating ROS and oxidative stress, each operating at a different stage of ischemia and reperfusion. In response to hypoxia, mitochondria generate an initial burst of ROS, which is curtailed once mitochondria depolarize or prevented by previous depolarization with uncoupler. A second phase of ROS generation that followed after a delay was blocked by the xanthine oxidase (XO) inhibitor oxypurinol. This phase correlated with a rise in [Mg2+]c, suggesting XO activation by accumulating products of ATP consumption. A third phase of ROS generation appeared at reoxygenation. This was blocked by NADPH oxidase inhibitors and was absent in cells from gp91phox–/– knock-out mice. It was Ca2+ dependent, suggesting activation by increased [Ca2+]c during anoxia, itself partly attributable to glutamate release. Inhibition of either the NADPH oxidase or XO was significantly neuroprotective. Thus, oxidative stress contributes to cell death over and above the injury attributable to energy deprivation
Aye–ay: An Anglo-Frisian Parallel
No full textThe most widespread form for neutral “yes” in the Survey of English Dialects is not yea or yes, but aye. It is used not only in the North and Midlands, but also in areas of the South of England. It is a feature of Scottish English, and is familiar from government in many English-speaking countries. We also find the aye-like ayuh in Northeast America. “Aye” appears suddenly about 1575 and is “exceedingly common” around 1600; it is initially written I and its origin, like yes, is uncertain. Ay is also found in Old Frisian, as well as Sater Frisian today (öäi, a'äi etc.). This study reviews a number of proposed etymologies, examining which can account for the occurrence or development of ay(e) in both languages. Based on a wider study of change in forms of “yes” and “no” in English, the author argues that aye–ay is a parallel development of interjection + particle. The study also suggests functional and phonological overlap with the pronominal echo I in English, but not Frisian, with the vocalic form of the pronoun and diphthongisation in the “Great Vowel Shift”, accounting for the popularity and spelling I of “aye” around 1600.</jats:p
Fucoxanthin promotes translocation and induction of glucose transporter 4 in skeletal muscles of diabetic/obese KK-Ay mice
No full textFucoxanthin (Fx) isolated from Undaria pinnatifida suppresses the development of hyperglycemia and hyperinsulinemia of diabetic/obese KK-Ay mice after two weeks of feeding 0.2% Fx-containing diet. In the soleus muscle of KK-Ay mice that were fed Fx, glucose transporter 4 (GLUT4) translocation to plasma membranes from cytosol was promoted. On the other hand, Fx increased GLUT4 expression levels in the extensor digitorum longus (EDL) muscle, although GLUT4 translocation tended to increase. The expression levels of insulin receptor (IR) mRNA and phosphorylation of Akt, which are in upstream of the insulin signaling pathway regulating GLUT4 translocation, were also enhanced in the soleus and EDL muscles of the mice fed Fx. Furthermore, Fx induced peroxisome proliferator activated receptor γ coactivator-1α (PGC-1α), which has been reported to increase GLUT4 expression, in both soleus and EDL muscles. These results suggest that in diabetic/obese KK-Ay mice, Fx improves hyperglycemia by activating the insulin signaling pathway, including GLUT4 translocation, and inducing GLUT4 expression in the soleus and EDL muscles, respectively, of diabetic/obese KK-Ay mice
Experimental method to quantify the efficiency of the first two operational stages of nanosecond dielectric barrier discharge plasma actuators
No full textA method to quantify the efficiency of the first two operational stages of a nanosecond dielectric barrier discharge (ns-DBD) plasma actuator is proposed. The method is based on the independent measurements of the energy of electrical pulses and the useful part of the energy which heats up the gas in the discharge region. Energy input is calculated via a back current shunt technique as the difference between the energy given and the energy reflected back. The ratio of the difference of the latter two quantities and the energy input gives the electrical efficiency (η E) of a ns-DBD. The extent of the energy deposited is estimated via Schlieren visualizations and infrared thermography measurements. Then, the ideal power flux obtained if all the inputted energy was converted into heat is calculated. Transient surface temperature was measured via infrared thermography and used to solve a 1D inverse heat transfer problem in a direction normal to the surface. It gives as output the actual power flux. The estimated ratio between the two power fluxes represents a quantification of the mechanical fluid efficiency (η FM) of a ns-DBD plasma actuator. Results show an inverse proportionality between η E, and η FM, and the thickness of the barrier. The efficiency of the first two operational stages of a ns-DBD is further defined as η = η E centerdot η FM
Population health and status of epidemiology: WHO European Region I
No full textBackground This article of the International Epidemiological Association commissioned paper series stocktakes the population health and status of epidemiology in 21 of the 53 countries of the WHO European Region. By United Nations geographical classification, these countries belong to Eastern Europe, Western Asia and South-Central Asia. Methods Published data were used to describe population health indicators and risk factors. Epidemiological training and research was assessed based on author knowledge, information searches and E-mail survey of experts. Bibliometric analyses determined epidemiological publication outputs. Results Between-country differences in life expectancy, amount and profile of disease burden and prevalence of risk factors are marked. Epidemiological training is affected by ongoing structural reforms of educational systems. Training is advanced in Israel and several Eastern European countries. Epidemiological research is mainly university-based in most countries, but predominantly conducted by governmental research institutes in several countries of the former Soviet Union. Funding is generally external and limited, partially due to competition from and prioritization of biomedical research. Multiple relevant professional societies exist, especially in Poland, the Czech Republic and Hungary. Few of the region's 39 epidemiological academic journals have international currency. The number of epidemiological publications per population is highest for Israel and lowest for South-Central Asian countries. Conclusions Epidemiological capacity will continue to be heterogeneous across the region and depend more on countries' individual historical, social, political and economic conditions and contexts than their epidemiologists' successive efforts. National and international research funding, and within- and between-country collaborations should be enhanced, especially for South-Central Asian countries
The Jewish imaginary of political Islamic though in Turkey the sample of Milli Görüş movement
No full textIn this thesis, it?s aimed to discuss the Jewish Imaginary of Milli Görüş Movement. At first we have to say that, if we literally translate the word ?milli? as ?national?, it will cause some misunderstandings. We can translate the concept of ?milli?, as ?religious?. We can find this concept (Bakara, 2/120, 135; Nisa, 4/125 etc? verses of Koran). It?s possible to describe shortly the ?Milli Görüş Movement?, a whole organization including the political parties, educational establishments, press, and labor unions, under the leadership of Necmettin Erbakan (the late president).In this thesis at first it?s examined the Jews in Islamic History and geography. The Jews from viewpoint of Christians and the other non-Muslim publics is another subject of this thesis.Arabs and other Muslim groups, the Jewish Imaginary of Turks, including Nationalists, Communists, and Left wings are some parts of contents of this study. At last the Jewish Imaginary of Milli Görüş Movement is the main subject of this thesis.We have interviewed with some important members of administrative committee of Milli Görüş, including the late president, the founder leader of this movement, Necmettin Erbakan. Conducting the poll is another source of information of this study. The concepts of Judaism, Jews, Anti-Semitism, Zionism, Christian Jews and Promised Land are also discussed in this thesis.The Milli Görüş is a dynamic Movement, not because its internal condition but also because of Turkey?s special conditions, it?s difficult to line of this movement. Some parties of this movement have banned through the extraordinary or the Constitutional courts of Turkey. As a result of this situation, cleavage of these parties is an inevitable manner.There are some different parties, including the government party AKP and the two others, that growth from Milli Görüş in Turkey.Today, it?s very difficult to determine which party and which party?s members are the real representatives the Milli Görüş. Not only in Turkey but also in European countries, there are many institutions belong to this movement.Doktora tezi olarak hazırlanan bu çalışmada, Türkiye'de son yarım yüzyılda genelde muhafazakâr kesimin desteklediği ve batılılar tarafından `Siyasal İslam' olarak adlandırılan Milli Görüş hareketinin, Yahudiler hakkındaki kanaatleri incelenmeye çalışılmıştır. Dinler Tarihi alanında tez olarak hazırladığımız bu çalışma sosyoloji, tarih, siyaset ve uluslararası ilişkiler gibi disiplinleri yakından ilgilendirmektedir. Çalışmamız bu alanların tümüyle bir şekilde alışveriş içine girmiş ve bu alanlara katkı yapmayı hedeflemiştir. Bununla beraber bu katkıların en önemlisi, çalışmanın bu alanda ülkemizdeki pek çok tartışmaya bilimsel bir alt yapı oluşturmasıdır. Bu yüzden çalışmamızda objektif ve bilimsel kriterlere uyulmaya gayret edilmiştir. Birinci bölümde, etraflıca anlaşılması için Yahudilik ve Yahudi tarihi hakkında bilgiler verilmiştir. Türkiye'de son yüzyıldaki Yahudilerle ilgili kanaatlerin değişmesinde son derece önemli olan Siyonizm ideolojisi, İsrail ve İsrail devletinin uygulamalarından kısaca bahsedilmiştir. İkinci bölümde, Milli Görüş hareketinin kurucusu Necmeddin Erbakan'ın hayatı ve kişiliği ile birlikte, hareketin tarihi süreci ve kurulduğu günden beri oluşturduğu kurumlar belirtilmeye çalışılmıştır. Bu noktada, hareketin ortaya çıkmasından günümüze kadar geçirdiği evreler dikkate alınarak, Erbakan'ın kişiliği ve fikirlerinin belirleyiciliği, Yahudilik ve dünyayı algılamadaki etkisinin boyutu ortaya konulmaya çalışılmıştır.Üçüncü bölümde, konunun daha iyi anlaşılması için genelde dünyada, özelde Milli Görüş hareketinde Yahudilerle ilgili kanaatleri belirleyen alanlar incelenmeye çalışılmıştır. Yine bu bölümde başta Erbakan olmak üzere parti yöneticileri ile yapılan görüşmeler, basında çıkan yazılar ve ropörtajlardan istifade edilmeye çalışılmıştır. Bu konudaki kanaatler mümkün olduğunca çeşitlendirilmeye çalışılarak farklı görüşler aktarılmış ve genel kanaat bulunmaya çalışılmıştır. Konunun daha iyi anlaşılmasına katkı sağlamak için Milli Görüş hareketinin dünyayı nasıl algıladığı, nasıl bir perspektifle olayları değerlendirdiği, bu tür bir perspektifin konuyla ilgili nasıl bir tesir bıraktığı değerlendirilmeye çalışılmıştır. Araştırmamızın son bölümünde ise hareketin mensuplarıyla yapılan anketler değerlendirilmiştir
Sequence effects in categorization of simple perceptual stimuli
No full textCategorization research typically assumes that the cognitive system has access to a (more or less noisy) representation of the absolute magnitudes of the properties of stimuli and that this information is used in reaching a categorization decision. However, research on identification of simple perceptual stimuli suggests that people have very poor representations of absolute magnitude information and that judgments about absolute magnitude are strongly influenced by preceding material. The experiments presented here investigate such sequence effects in categorization tasks. Strong sequence effects were found. Classification of a borderline stimulus was more accurate when preceded by a distant member of the opposite category than by a distant member of the same category. It is argued that this category contrast effect cannot be accounted for by extant exemplar or decision-bound models of categorization. The effect suggests the use of relative magnitude information in categorization. A memory and contrast model illustrates how relative magnitude information may be used in categorization
Evaluierung von sechs Fotofallenmodellen hinsichtlich der Eignung für Fang-Wiederfang Methoden beim Eurasischen Luchs (Lynx lynx)
No full textDigital outdoor cameras are increasingly used in wildlife research because they allow species inventories, population estimates, and behavior or activity observations. Which camera model is suitable and practical depends on environmental conditions, focus species and specific scientific questions posed. Here we focused on testing cameras appropriate for elusive species that can be identified visually owing to individual coat patterns. Specifically the camera should be adequate for calculating the minimum population of Eurasian Lynx (Lynx lynx) during a systematic monitoring with camera traps. Therefore we tested six digital camera models with regard to trigger speed and the image quality necessary for visual identification of pacing lynx on trails. The decision if a camera model is adequate for the scientific goal was regulated due to priority levels under laboratory conditions. Only one camera model proved to be suitable for camera-trap monitoring. Our practical camera test can be used to evaluate newer models of digital cameras as they become available. This application opens an avenue for a non-invasive population monitoring of rare and elusive species in a low mountain range area.Digitale Fotofallen werden weltweit in der Wildtierforschung eingesetzt. Die Einsatzgebiete sind vielfältig, sie reichen von Artenbestandsaufnahmen und Populationsschätzungen über die Verhaltensforschung bis hin zu Aktivitätsanalysen. Das jeweilig eingesetzte Kameramodell muss an die Aufnahmesituation und die Zielsetzung der Analyse angepasst sein. Das Ziel unseres Fotofallentests war es, ein Modell zu finden, welches für die visuelle Identifizierung von Fellmustern des Eurasischen Luchses geeignet ist. Die Fotofalle soll in einem systematischen Monitoring für die minimale Anzahl der im Gebiet vorkommenden Luchse und deren Populationsschätzung mit Fang-Wiederfang Methoden eingesetzt werden können. Bei dem Test von sechs Fotofallenmodellen, fiel das Hauptaugenmerk auf die Auslösegeschwindigkeit und die Bildqualität welche die nötigen Faktoren für die Sicherstellung der visuellen Identifikation von schreitenden Luchsen am Wildwechsel darstellen. Zur Entscheidungsfindung der Eignung eines Fotofallenmodells für die Fragestellung definierten wir Prioritätslevel unter Laborbedingungen. Es stellte sich heraus, dass nur ein Fotofallenmodell die Ansprüche erfüllte. Der praktische Fotofallentest kann für neuerscheinende Fotofallenmodelle adaptiert werden. Diese Anwendung eröffnet die Möglichkeit für ein nicht invasives Monitoring in Mittelgebirgslandschaften
SARS-CoV-2 lineage dynamics in England from September to November 2021: high diversity of Delta sub-lineages and increased transmissibility of AY.4.2
No full textBackground: Since the emergence of SARS-CoV-2, evolutionary pressure has driven large increases in the transmissibility of the virus. However, with increasing levels of immunity through vaccination and natural infection the evolutionary pressure will switch towards immune escape. Genomic surveillance in regions of high immunity is crucial in detecting emerging variants that can more successfully navigate the immune landscape. Methods: We present phylogenetic relationships and lineage dynamics within England (a country with high levels of immunity), as inferred from a random community sample of individuals who provided a self-administered throat and nose swab for rt-PCR testing as part of the REal-time Assessment of Community Transmission-1 (REACT-1) study. During round 14 (9 September–27 September 2021) and 15 (19 October–5 November 2021) lineages were determined for 1322 positive individuals, with 27.1% of those which reported their symptom status reporting no symptoms in the previous month. Results: We identified 44 unique lineages, all of which were Delta or Delta sub-lineages, and found a reduction in their mutation rate over the study period. The proportion of the Delta sub-lineage AY.4.2 was increasing, with a reproduction number 15% (95% CI 8–23%) greater than the most prevalent lineage, AY.4. Further, AY.4.2 was less associated with the most predictive COVID-19 symptoms (p = 0.029) and had a reduced mutation rate (p = 0.050). Both AY.4.2 and AY.4 were found to be geographically clustered in September but this was no longer the case by late October/early November, with only the lineage AY.6 exhibiting clustering towards the South of England. Conclusions: As SARS-CoV-2 moves towards endemicity and new variants emerge, genomic data obtained from random community samples can augment routine surveillance data without the potential biases introduced due to higher sampling rates of symptomatic individuals. © 2022, The Author(s)
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