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Summary A prospective study about the distribution and the sensitivity of 534 Gram negative bacilli isolated from urinary tract infections in office practice was done at Cotonou (Benin). Three major species were identified : Escherichia coli (36 %), Klebsiella spp (25 %), Proteus spp (13,9 %). The most of the strains presented a high level of resistance to ampicillin, cephalothine, tetracycline and cotrimoxazole, but the second and third cephalosporin generation (cefotixin, cefotaxime) were efficient against almost strains as well as imipenem, gentamicin and quinolones. The multiresistance (18 % of strains), concerned essentially Pseudomonas aeruginosa, Acinetobacter, Klebsiella and Enterobacter. Those results indicated that a periodical survey of sensibility of major pathogenic bacterial is useful of therapeutic choice and rational use of the antibiotics in office practice at Cotonou.

Objective: This study is aimed to investigate the effect of thermal cycling and microhardness on surface roughness of four different composite restorative materials. Materials and Methods: In this study Nonofilled(Ivoclar Heliomolar, 3M ESPE Filtek Supreme) and microhybrid(3M ESPE Filtek Z250, Kuraray Clearfil AP-X) composites were used. The surface roughness (Ra) was initially measured in a profilometer using a cut off 0,25mm, after 6000 and 12000 thermal cycles. In addition to microhardness of composites Vicker hardness (HV) were determined. Data were subjected to Anova and Tukey's test.(α=0,05). Results: One-way Anova indicated significant differences in Vicker hardness(HV) between four composite resins. Significant lowest HV was found for Heliomolar (HV=22); mean values were considerably lower than three composite resins. In addition to overall 6000 thermal cycles increased the surface of roughness values for all materials and there was a trend in all groups to decrease the roughness after 12000 thermal cycles. Conclusion: The material composition including type of organic matrix could be more relevant to roughness maintenance over time than the general behavior of composites based on particle fillers. Moreover, this study revealed that correlations between microhardness (HV) and surface of roughness were poor.

Understanding losses in polymer electrolyte membrane fuel cells, in the form of ohmic and mass transport, is of great importance to their commercialization. In this study, we use a spatially resolved cell consisting of 49 segments to measure the local current density distribution and high frequency resistance (HFR). A parametric study is used to investigate the effects of cell voltage, inlet relative humidity and flow rate and configuration using a three-channel serpentine flow field. We found that as the cell voltage decreased, the current density increased, while the HFR decreased. However, at a low cell voltage of 200 mV, we found the HFR to be higher than that at 500 mV. This increase is attributed to the increased electro-osmotic drag. This trend is independent of the flow configuration. Further, we found that the effect of the inlet relative humidity on the HFR highly depends on the flow configurations. Finally, a sharp decrease in the current density at some specific bend segments was observed, which correlates with lower OCV values and higher HFR values at this position.

Ein Pin-Up ist die zwei-dimensionale Darstellung einer Frau in üblicherweise erotischer Pose, wobei das Vorhandensein sowie der Grad von Erotik sich daran erkennen lassen, dass mindestens drei Kriterien, aus einer von mir erstellten Liste, für die dargestellte Frauenfigur zutreffen. Auf Basis dieser von mir persönlich formulierten Definition versuchte ich in meiner Diplomarbeit eine Reihe unterschiedlicher sozialer, politischer, wirtschaftlicher und historischer Aussagen und Merkmale aus US-amerikanischen und österreichischen Pin-Up-Bildern aus den 1930ern und 1950ern herauszufiltern und anschließend zu vergleichen, um zu zeigen, dass man auch aus einem ‚Lustbildchen’ mehr herauszulesen vermag, als nur vergangene Vorlieben. Eines meiner wichtigsten Analyseergebnisse von US-amerikanischen Pin-Ups beider Jahrzehnte ist beispielsweise, dass diese als typische Merkmale ein stets gepflegtes, adrett gekleidetes, freundlich wirkendes, gut aussehendes, junges Erscheinungsbild einer ausnahmslos weißen Frau voraussetzen, mit dramatischer Mimik und deren Weiblichkeit noch durch gewisse Attribute wie hohe Stöckelschuhe, gebogene Fußstellungen und feminine Bekleidung wie Röcke und/oder Kleider akzentuiert werden. In den 30er Jahren wurden hierbei andere, fantasievollere Motive bevorzugt. Waren in den 50ern die Thematiken eines ungeschickten Mädchens in einer misslichen Alltagssituation mit dem Frauentyp des ‚netten Mädchens von nebenan’ beliebt, lässt sich bei deren Vorgängern ein klarer Hang zu Pin-Ups erkennen, welche sich von Motiven der Femme Fatale und Szenerien aus Hollywoodfilmen inspirieren ließen. Diese dienten in ihrer Aufmachung, Pose und Motivwahl wohl zur Realitätsflucht aus einem, von der Großen Depression geprägten Alltag, sowie zur Befriedigung sexueller Gelüste. Erstaunlich ist es jedoch, dass angesichts der Weltwirtschaftskrise ein stabiles Preisniveau und eine gleichbleibende, farbenfrohe Qualität bei den veröffentlichten Pin-Ups zu verzeichnen war, welches die Wichtigkeit und Popularität der Pin-Ups in harten Zeiten betont. Werbe-Pin-Ups waren hierbei aber, aufgrund strenger Zensurbestimmungen, oftmals noch nicht sehr erotisch aufgemacht und sollten erst in den 50ern mittels der häufig angewandten Zweckentfremdung von reizvollen Pin-Ups in großer Auflage erscheinen. Dabei treten auch neue Komponenten auf, wie beispielsweise der Einsatz von Humor und kleinen storyplots. Die beigefügten Texte dienten in den USA, anders als in Österreich, nicht maßgeblich der Informationen über das Produkt oder das Pin-Up, sondern waren primär humoristische Wortspiele sowie dezente Hinweise auf die eigentlich beworbene Ware. Des Weiteren bedienen US-amerikanische Pin-Ups durchaus häufig landestypische Klischees wie beispielweise das Motiv des US-Cowgirls, was in Österreich niemals üblich war. Nackte Mädchen wurden aber, sowohl in den USA wie in Österreich, in beiden Jahrzehnten nicht oft porträtiert. In Österreich hingegen weisen die Männer-Pin-Ups der 1930er Jahre ein derartig geringes, erotisches Potenzial auf, dass sich manche nicht einmal mehr als Pin-Up kennzeichnen lassen, obwohl sie beispielsweise eine Frau in Bademode zeigten. Im Bereich der Werbe-Pin-Ups lassen sich hingegen in den 30ern einige Merkmale US-amerikanischer Pin-Ups erkennen, wie beispielsweise die Motivwahl der Femme Fatale, doch wurden diese immer stark abgemildert, um das, meist weibliche Zielpublikum nicht durch die Darstellung übermäßiger Sexualität vom Kauf des Produktes abzuschrecken. Auch die dortigen Zensurauflagen bestimmten maßgeblich den Grad des zur Schau gestellten erotischen Potenzials, allerdings konnten sich Werbekampagnen für männlich assoziierte Produkte mehr Freiheiten erlauben als Kampagnen für Frauenprodukte. Eine weitere Charakteristik aller österreichischen Werbe-Lustbilder stellt die offensichtliche Beziehung zwischen Pin-Ups und dem jeweiligen Produkt dar, da die Bewerbung von Bademoden und Unterwäsche mit hübsch anzusehenden Frauen weniger fern liegt, als etwa die Anpreisung eines Telefondienstes durch ein US-Cowgirl, welches das Produkt meistens durch das übermäßige Sex-Sells-Credo zur Nebensächlichkeit werden ließ. Österreich wirkte dieser Herabsetzung entgegen, indem hier zwei Werbe-Strategien eingesetzt wurden, welche einerseits eine sehr konservative Klientel ansprach und andererseits auch vermehrt auf Pin-Ups im Stile US-amerikanischer Vorbilder einsetzte, um jüngere und/oder modernere Kundinnen anzuwerben. In den 50er Jahren wurden zwar noch ähnliche Maßnahmen zur Entsexualsierung der Pin-Ups ergriffen, doch traten zeitgleich auch moderne, farbenfrohe und im Stil US-amerikanischer Pin-Ups gehaltene Bildnisse auf, welche erste Anzeichen für eine gewisse Aufgeschlossenheit gegenüber amerikanischen Produkten, Zeichenstilen, Lebensgefühlen und Marketingstrategien vermuten lässt. Dies spiegelte auch die gesellschaftliche Bipolarität zwischen Moderne/Amerikanismus und Traditionalismus wieder., A Pin-Up is characterized by a two-dimensional depiction of a usually very erotic woman. The sexual potential of this depiction composes of the accordance of three criteria from a self-made list by the author. Based on this definition I tried in my diploma thesis to extract some social, political, economical and historical knowledge and the most common characteristics of US-American and Austrian Pin-Ups from the 1930s to the 1950s to prove the deeper value of such sexy drawings. An abstract of the most important results shows that US-American Pin-Ups from the 1930s to the 1950s always depicted a young, beautiful, friendly and unexceptionally white woman, with a shining smile or pursed lips and always wearing feminine clothes such as dresses and skirts in combination with kitten-heeled shoes or elegantly bended feet. Fantastic themes based on the latest Hollywood movies were the most popular in the US to mentally flee from the hardships suffered during the Great Depression and, surely, to satisfy some sexual longings, while the Swinging Fifties brought up a new type of Pin-Up-Girl, the ‘the nice Girl next door’, who is characterized by a young girl in a difficult situation from everyday life. Interestingly enough there has never been a decline in price or quality of Pin-Up-Magazines from the 1930s to the 50s, which proves my point, that Pin-Ups were an important and much desired element to keep the morals up during financial crises and wars. However, Pin-Ups especially made for advertisements still had a long way to go into public since the morals and censorship did not loose their tight grip on the Pin-Up industry before the post-war time, which was the time of new, humorous Promotional-Pin-Ups using detailed storyplots and humorous wordplays. In addition they were often characterized by the ‘misuse’ of sexual Pin-Ups advertising for such banal products such as car spares or dentists chairs. Naturally, the Pin-Up-Girl was often more interesting to look at than the proclaimed product. In contrast, many Austrian depictions of woman in bathing clothes or underwear from the 1950s to 1930s were so unerotic, that they could not even be defined as a Pin-Up, even though some of them were clearly inspired by US-American examples. However those Pin-Ups characterized as such, were often used in advertisement, which explains why their sexual potential was often diminished to a minimum in order not to scare of or insult the, mostly female customers. The censorship at that time was as strict as in the USA, but advertisement designed for male products was granted a little more freedoms to imply sexual sub-messages than for campaigns dedicated to female clients. Portraying a woman wearing underwear or bathing clothes in a sexy pose does not seem as surprising as advertising a phone service by a sexy US-Cowgirl, which shows that Austrian commercial Pin-Ups had a far more logical relationship between the proclaimed product and the Pin-Up, than in the US, where the general credo said ‘Sex sells’. Austrian commercial companies tended to use a dual strategy during the 50s, using conservative advertisements to attract a less modern clientele and simultaneously showing new, colourful and sexy Pin-Ups Girls to fulfil the dreams and desires of a younger generation, both male and female, longing for an American Style of Life and Pin-Ups. This also proves the deeply rooted fight in the Austrian post-war society between those proclaiming modernism and Americanism and the others holding on to traditions and old morals. Last but not least there were the Pin-Ups made of Cliché-motives such as the US-Cowgirl, Indian Girls or Hampton Beach Sailor- Girls, which were much beloved in the USA for many decades but less accepted and therefore rarely used in Austria. But interestingly enough there were less naked Pin-Up Girls published in both, the USA and Austria during the 1930s to the 1950s, as one might have guessed, which might be due to the reasons of a strict censorship in the 30s and the fact being, that nudity is less suitable for the moral messages represented by a ‘nice Girl next door’ in the USA or the already less sexualised commercial campaigns and Pin-Up Magazines in Austria.

The effect of hard anodizing coated 2014-T6 aluminium alloy test samples with dissimilar mating materials on fretting fatigue was investigated. Fretting fatigue configuration involved bridge-type pads on the flat specimen. Bridge-type pads were made of AISI 4140 steel. All the fretting fatigue tests were conducted under plane bending loading with a stress ratio of R = -1. Coated and uncoated specimens were compared for microhardness, surface roughness, tangential force. The specimens were tested under both plain fatigue and fretting fatigue loading at ambient temperature. Micrographs obtained from scanning electron microscope showed that hard anodizing coating had tiny cracks through the thickness of the anodized layer. The hardness of hard anodized coating was higher than that of uncoated specimens and they also exhibited lower tangential force. However, the fretted region of the hard anodizing coated specimens was rougher than that of uncoated samples and despite lower tangential forces, fatigue lives of hard anodizing coated samples were inferior to those of uncoated samples. As the hard anodizing coating had pre-existing tiny cracks and tension residual stress, cracks propagated from the hard anodizing coating through the interface into the substrate. We conclude that these may be the main reasons for inferior fretting fatigue lives compared with uncoated samples.

But de la presentation L’amplification du gene codant pour FGFR1 par des lignees tumorales pulmonaires a ete correlee a une meilleure sensibilite aux inhibiteurs tyrosine kinase anti-FGFRs (1). Cette amplification est retrouvee dans 17 % des carcinomes epidermoides des voies aerodigestives superieures (VADS) (2), ce qui incite a determiner si cette amplification nous permettrait de selectionner les patients susceptibles de repondre a une potentielle therapie ciblant les FGFRs. Materiel et methodes Le BGJ398 est un inhibiteur tyrosine kinase specifique des FGFR1/2/3. Nous avons etudie son effet sur des lignees tumorales de carcinome epidermoide des VADS (CAL27, CAL33, HN et SCC-25) par etude de la viabilite cellulaire (WST-1) et de l’entree en apoptose (Annexine V/iodure de propidium). Les lignees HN et SCC-25 sont decrites pour presenter une amplification genique de FGFR1. Nous avons verifie la presence de cette amplification genique par hybridation in situ en fluorescence (FISH) et etudie le profil d’expression en FGFRs/FGF2 par RT-qPCR et Western Blot afin de comprendre les differences de sensibilite inter-lignees. L’association du BGJ398 avec le cisplatine a egalement ete evaluee selon la methode de Chou et Talalay permettant de definir s’il existe une synergie ou un antagonisme. Resultats Le BGJ398 presente un effet cytotoxique sur trois des quatre lignees etudiees. La concentration inhibitrice 50 (CI50) du BGJ398 sur les lignees CAL27, CAL33 et HN est de l’ordre de 4 μM alors qu’elle est superieure a 15 μM sur SCC-25. Cette derniere presente une resistance a l’apoptose alors que les taux d’apoptose apres traitement par BGJ398 sont de l’ordre de 80 % sur les lignees CAL27, CAL33 et HN. Par ailleurs, l’etude de l’association therapeutique montre un effet antagoniste entre BGJ398 et cisplatine. Conclusion L’amplification genique de FGFR1 ne semble donc pas etre un marqueur predictif de reponse au BGJ398 en ORL et l’association BGJ398/cisplatine n’est pas pertinente in vitro dans un schema de traitement concomitant.

The performance and stability of a hydrogen-driven polymer electrolyte membrane fuel cell stack (6-cell PEFC stack) are investigated with regard to pore flooding within the gas diffusion layers (GDLs). Two short stacks with various GDLs (Toray TGP-H-060 untreated and laser-perforated) were characterized at different operating conditions by several characterization techniques such as constant current load, polarization curve, chronoamperometry and chronovoltammetry. The experimental results reveal that the perforation of the cathode GDLs improves the water transport in the porous media and thus the performance as well as the stability of the operating stack in medium and high current density range. A reduced pore flooding is verified when using the customized laser-perforated GDLs. The GDL perforation has a huge potential to balance the inhomogeneous in-plane saturation conditions between the inlet and outlet area of the cell and to compensate to a certain degree the effects of temperature distribution within a stack regarding the water management.

An investigation has been carried out in order to study the fretting fatigue behavior of a 2014-T6 aluminum alloy, which has been coated with a commercial hard anodizing of approximately 20-25 mu m in thickness. The hardness (HV) was significantly improved up to about 380 after hard anodizing coating while the hardness value of original 2014-T6 was 175. Fretting reduced drastically the fatigue life of samples in both conditions, substrate and coated conditions. The application of such a coating to the substrate may increase the fretting fatigue life in comparison with the uncoated samples in low-stress region for rotating bending fatigue loading while at higher stresses the effect of anodizing is reversed. This may be result from early initiation of cracking of hard anodizing film due to high-stress concentration resulting from bulk stresses. On the other hand, the increase in fretting fatigue life in low-stress region may be probably attributed to low coefficient of friction that prevents metal-to-metal contact, which may result in higher fretting fatigue life because of retardation of crack initiation resulting from lower stress concentration compared to the substrate.

Bu çalışmada mühendisliktasarımında kullanılan klasik yöntem ile son zamanlarda yaygın bir kullanımalanı bulmaya başlayan &asılı& dayalı tasarım metodu karılaştırılmalıolarak verilmiştir. İlk olarak gerilme-dayanım yaklaşımı verilmiş ve buna bağlıolarak geliştirilen FOSM (birinci-derece ikinci moment yaklaşımı detaylı olarakanlatılmış ve bu yöntemin eksikliklerin gidermek amacıyla geliştirilen FORM(birinci-dereceden güvenilirlik yöntemi) ve SORM (ikinci-dereceden güvenilirlikyöntemi) yöntemleri verilmiştir. Bu yöntemlerden farklı olarak simülasyonadayanan Monte Carlo Simülasyonu anlatılmıştır. Verilen bu yöntemlerin uygulanışıbir örnek vasıtasıyla gösterilmiştir.&nbsp

ÖZET Doktora Tezi ÖN ŞEKİL DEĞİŞTİRME İLE OLUŞTURULAN ARTIK GERİLMELERİN YORULMA DAVRANIŞI ÜZERİNE ETKİSİNİN İNCELENMESİ Recep Sadeler Atatürk Üniversitesi Fen Bilimleri Enstitüsü Makine Mühendisliği Anabilim Dalı Danışman : Doç.Dr. Adnan Özel Mühendislik malzemelerinin yorulma davranışları üzerinde artık gerilmelerin dikkate değer bir etkisi vardır. Orta ve yüksek sertlikli malzemelerin yüzey bölgelerinde mekanik, termik, veya termokimyasal işlemler ile oluşturulan bası artık gerilmeleri, dinamik yüklemeye maruz malzemelerde yorulma özelliklerini geliştirebilir. Bu çalışmada, iki farklı ısıl işlem uygulanmış AISI 4140 ( normalizasyon ve yağda- soğutulup-temperleme ) çeliğinden imal edilmiş farklı çentik yarıçaplarına ( r=l, 1.5 ve 2mm ) sahip numunelerde, ön şekil değiştirme işlemi ile oluşturulan bası artık gerilmesinin yorulma özellikleri üzerindeki etkisi araştırılmıştır. Yorulma deneyleri döner eğilmeli test ( R=-l ) cihazında gerçekleştirilmiştir. Söz konusu yöntem ile oluşturulan bası artık gerilmelerinin çentik bölgesindeki dağılımı geliştirilen sonlu eleman yöntemi ( SEY ) ile belirlenmiştir. SEY çözümünden elde edilen artık gerilme sonuçları, ANSYS 5.7 ile karşılaştırılmış ve sonuçların oldukça uyumlu olduğu saptanmıştır. Çentik bölgesinde artık gerilmelerin bir konsantrasyon etkisi gösterdiği, bu etkinin malzeme geometrisine ilaveten malzemenin mukavemetine de bağlı olduğu, bu bölgedeki artık gerilme dağılımından belirlenmiştir. Gerilme değişiminin söz konusu olduğu çentik civarında, ön şekil değiştirme ile oluşturulan bası artık gerilmelerinin yorulma ömrü üzerinde en büyük etkiye sahip olduğu saptanmıştır. Malzemenin sertliği, akma mukavemeti, çentik etkisi ve seçilen ön yükleme oranı (yükleme genliğine) gibi parametrelerin, bası artık gerilmesinin söz konusu etkisini değiştirme yeteneğine sahip önemli değişkenler olduğu saptanmıştır. Metallografik incelemeler için optik mikroskop, SEM ( taramalı elektron mikroskobu ), ve X-ışınları yansıması yöntemleri kullanılmıştır. 2002, 137 sayfa Anahtar kelimeler : Yorulma, artık gerilmeler, sonlu eleman yöntemi ABSTRACT Ph.D.Thesis THE INVESTIGATION OF EFFECT OF RESIDUAL STRESSES INDUCED BY PRE-STRAINING ON FATIGUE BEHAVIOUR Recep Sadeler Atatürk University Institute of Applied Science Department of Mechanical Engineering Supervisor : Doç.Dr. Adnan Özel Residual stresses have significant effects on the fatigue behaviors of engineering materials. The compressive residual stresses which are induced on the surface region of the materials with medium and high hardness by mechanical, thermal and thermo- chemical processes may improve the fatigue properties of the materials subjected to dynamic loadings. In this study, the effect of the compressive residual stresses on the fatigue properties are investigated in the samples with different radius (r =1, 1.5 and 2 mm) manufactured from AISI 4140 steel for which two different heat treatments (normalized and oil quenched-tempered) were applied. The fatigue tests are carried out at the rotating bending (R=-l) test machine. The distribution of the compressive residual stresses induced by the process mentioned in the notch region is determined by the Finite Element Method ( SEY ) developed by the author. The results of the residual stress are compared with that of ANSYS 5.7, and it is found that the results are quite coincident. It is observed from the distribution of the compressive residual stress in the notch that the residual stress exhibits a concentration effect in the notch region, which is dependent on the material strength as well as the material geometry. In the vicinity of the notch subjected to the stress gradient it is also determined that the compressive residual stresses induced by pre-straining have the most significant effect on the fatigue life. The parameters such as the hardness of the material, the yielding stress, the notch effect and the selected stress amplitude are appeared as the important parameters that have the ability of changing the mentioned effect of the compressive residual stress. Optic microscope, SEM (Scanning Electron Microscope) and X-ray are used for the metallographic studies. 2002, 137 pages Keywords : Fatigue, residual stresses, finite element method 138

Meyvecilikte seyreltme, meyve kalitesini artırmak amacıyla tatbik edilen kültürel işlemlerden birisidir. Golden ve Starking Delicious elma çeşitlerinde 1995-96 yıllarında, Tortum (Erzurum)'da yürütülen bu çalışmada, bazı seyreltme uygulamalarının meyve seyrelme oranı, meyvenin bazı fiziksel ve kimyasal özellikleri üzerine olan etkileri incelenmiştir. Her iki yılda da bütün uygulamalar kontrole göre meyve seyrelme oranını artırmıştır. Hem Golden, hem de Starking Delicious elma çeşitlerinde elle seyreltme uygulamalarının % 90'lık dozu en yüksek seyrelmeyi sağlamıştır. Kimyasal uygulamalarda ise Golden Delicious'ta 10 ppm NAA (1. yıl % 89.03, 2. yıl % 88.17), 40 ppm NAAm (1. yıl % 87.60, 2. yıl % 88.12), Starking Delicious'ta ise 40 ppm NAA (1. yıl % 86.84, 2. yıl % 88.86) ve 20 ppm NAAm (ilk yıl % 89.77, ertesi yıl % 80.74)'in nispeten yüksek düzeyde seyreltici etki yaptıkları tespit edilmiştir. Seyreltme uygulamaları kontrole göre meyve ağırlığı, meyve hacmi, meyve boyu ve meyve çapında artış meydana getirmiştir. Golden Delicious'ta 1995-1996 yıllarında doza göre değişmekle birlikte meyve ağırlığında % 56 - 78, meyve hacminde % 49 - 61, meyve boyunda % 13 - 30, meyve çapında % 26 - 26 arasında; Starking Delicious'ta ise meyve ağırlığında % 57 - 80, meyve hacminde % 96 - 64, meyve boyunda % 14 - 28, meyve çapında da % 8 - 18 düzeylerinde bir artışın meydana geldiği saptanmıştır. Her iki çeşitte de, seyreltme uygulamaları sonucunda, meyvenin bazı kimyasal özellikleri (SÇKM, pH, titre edilebilir asit, toplam şeker, indirgen şeker) kontrolden istatistiki olarak farklı bulunmuştur. Golden Delicious çeşidinde 1995 ve 1996 yıllarında sırasıyla SÇKM'nin % 12.43 - 14.91 ve % 12.25 - 14.34; pH'nın 2.97 - 3.34 ve 3.00 - 3.41; titre edilebilir asit içeriğinin % 0.19 - 1.05 ve % 0.32 - 0.79; toplam şeker % 8.72 - 12.09 ve % 10.39 - 11.95; indirgen şekerin de % 7.17 - 8.00 ve % 8.31 -10.03 arasında değiştiği belirlenmiştir. Starking Delicious'ta ise SÇKM'de % 50'lik elle seyreltme (% 15.10 ve % 13.85); pH'da 40 ppm'lik NAAm (3.37 ve 3.87); titre edilebilir asitte 10 ppm'lik NAA (% 0.64 ve % 0.52); toplam şekerde 10 ppm'lik NAAm (% 11.47 ve % 11.24); indirgen şekerde ise 10 ppm'lik NAAm (% 8.39 ve % 8. 14) 'in her iki yılda da kontrole göre daha iyi sonuçlar verdiği ortaya çıkarılmıştır. Ayrıca seyreltme uygulamalarında, meyve büyüme hızının kontrolden daha iyi olduğu saptanmıştır. Thining of fruit is one of the important cultural method to increase quality of fruit in fruit culture. This study was undertaken to determine the effects of some thining methods on ratio of fruit thining, physical and chemical characteristics of fruit of Golden and Starking apple varieties in 1995 and 1996. Ratio of thining increased with all thining application when compare to control in both of the years. The highest thining levels were obtained with 90 % of hand thining application in Golden and Starking Delicious varieties in two years. Application of 10 ppm and 40 ppm of NAA on Golden Delicious increased thining ratio as 89.03 % and 87.60 % in the first year and 88.17 % and 88. 12 % in the second year, respectively. Also, application of 40 ppm and 20 ppm of NAA on Starking Delicious increased levels thining as 86.84 % and 89.77 % in the first year and 88.86 % and 84.74 % in the second year, respectively. Fruit weight, fruit volume, fruit lenght and fruit size increased with thining application compared to control. Their values were as fallows; 56-78 % fruit weight, 49-61 % fruit volume, 13-30 % fruit lenght and 26-26 % fruit size in Golden Delicious and 57-80 % fruit weight, 96-64 % fruit volume, 14-28 fruit lenght and 8-18 % fruit size in Starking Delicious based on applying of different doses in 1995 and 1996 there were statistically difference about some chemical characteristics of fruit such as TSS, pH, titrable acidy, total sugar and induced sugar when compare to control depend on thining applications both of the cultivars. TSS, pH, titrable acidity, total sugar and induced sugar ranged 12.43- 14.91 % and 12.25-14.34 %, 2.97-3.34 and 3.00-3.41; 6.19-1.05 % and 0.32-0.79 %, 8.72-12.09 % and 39. 11-1 1.95 %; 7.17-8.00 % and 8.31-10.03 % in Golden Delicious in 1995 and 1996, respectively. In Starking Delicious, chemical characteristics values were higher than control in both of the years. The characteristics were as fallows; 18. 10-13.85 TSS at 50 % of hand thining, 3.37-3.87 pH at 40 ppm of NAA, 0.64-0.52 % titrable acidity at 10 ppm at NAA, 11.47 -1 1.24 % total sugar at 10 ppm of NAA, 839-8.14 % in duced sugar at 10 ppm of NAA applications. In addition, fruit applied thining developed well when compared to control. 59

Çarpışma konusu her zaman malzeme ve yapılardaki dalga yayılmasını ihtiva eder. Düşük çarpma hızlarında sadece elastik dalgalar oluştuğu için, gerilmeler malzemenin akma gerilmesinin altodadır. Yüksek çarpma hızlarında gerilmeler akma gerilmesini aşacak ve elastik dalgalara ilaveten elastik olmayan dalgalarda oluşacaktır. Taylor çarpma (impact ) testi modern mekanikte üzerinde en çok çalışılan konulardan biri olup, bu işlemde silindirik eleman rijid bir hedefe yüksek bir hız ile çarptırılır. Tepkinin fiziksel yapısını seçilen l/d oram ve çarpma hızı belirleyecektir. Bu çalışmada ANSYS 5.0 A kullanılarak, Al, X12CrNi 18 -8 paslanmaz çelik ve Cu'dan imal edilmiş silindirik elemanların, her bir işlemde geometrilerinin (l/d oram) sabit, çarpma hızlarının değiştiği kabul edilerek, kalıcı şekil değiştirmeler ve gerilme dağılımları analiz edilmiştir. The study of impact phenomena invariably involves the propagation of stress waves in materials and structures. At low impact velocities, stresses may be below the yield strength of the material so that only elastic stress waves are generated. In the case of high velocity impacts, stresses will exceed the yield strength and inelastic waves as well as elastic waves will be generated.. Taylor impact test is one of the most thoroughly studied problems in modern mechanics. In this process, a cylindrical projectile is striked with a high velocity to a rigid boundary. The physics of the response will be governed by choice of 1/d ratio and striking velocity. In this study, deformation and stresses distribution was analysed by using ANSYS 5.0 for the cylinders fabricated from aluminium, stainless steel, copper which was assumed that 1/d ratio is constant as striking velocities are verified. 92

Eleven antibiotics were tested against 1,194 Gram negative bacilli isolated from urinary tract infections at the National University Hospital Center at Cotonou. Among the betalactams tested, only cefotaxime remained active against most of the bacteria tested: 90% of the strains of Escherichia coli and 75% of the strains of Enterobacter cloacae were sensitive. Ampicilline, on the other hand, had lost its activity even on strains which are usually the most susceptible. Thirteen percent of the E. coli strains were sensitive. This reduction in antibiotic activity against bacterial strains in Cotonou, which concerned to various degrees the tetracyclines, chloramphenicol, cotrimoxazole, is less pronounced for the amino-sides (gentamicine and netilmicine), and the quinolones of which nalidixique acid was active against 83.9% of the strains of E. coli. The low frequency of isolation of wild type strains (sensitive to betalactams) is probably the consequence of strong selection pressure due to a massive, and uncontrolled use of antibiotics in Cotonou.

gamma delta T cells bearing V gamma 9 T cell receptors from unexposed Caucasian donors make large responses to Plasmodium falciparum in vitro. This finding, together with observations of others showing high levels of V gamma 9+ T cells in the blood of infected non-immune individuals, led us to hypothesize that the response of these cells might contribute to the pathology of P. falciparum malaria. Acquisition of immunity to disease in people naturally exposed to infection may therefore be due in part to down-regulation or alteration of the function of gamma delta T cells. Supporting this view, and in contrast to infection in non-immune individuals, V gamma 9+ T cells are not elevated in peripheral blood of children or adults living in an endemic area despite constant exposure to P. falciparum. After in vitro stimulation with P. falciparum, however, the expansion of V gamma 9+ cells from the African donors is of similar magnitude to that observed for non-exposed Europeans. Thus, although these cells are not elevated in peripheral blood, they are still able to respond to P. falciparum antigens. In adult European donors the major gamma delta T cell population in peripheral blood is V gamma 9+ (approximately 70% of all gamma delta cells), whereas in the majority of adult Africans V delta 1+ V gamma 9- T cells predominated (approximately 70% of total gamma delta cells).

We studied the prevalence of human onchocerciasis in four geographically different regions of the southern part of Benin in West Africa. In a total of thirteen villages 1596 individuals were examined for clinical and parasitological signs of onchocerciasis. Prevalence of microfilariae of Onchocerca volvulus in skin snips was 29% in region I (lower Oueme river), 64% in region II (Mono river), 56% in region III (upper Oueme river) and 70% in region IV (Okpara river). Based on endemicity criteria of the WHO regions II and IV were found to be hyperendemic, region III mesoendemic and region I hypoendemic for onchocerciasis. The community microfilarial load ranged from 4 mf/mg skin in the hypoendemic region to 10.5 mf/mg skin in the hyperendemic regions. The prevalence of nodules was 21% in region I, 30% in region II, 17% in region III and 41% in region IV. The overall prevalence of chronic onchocercal dermatitis was 12%. Of 689 individuals infected with O. volvulus 388 were treated with a single dose of ivermectin.

In Benin, women's social status determines the number of births. In fact, a woman's attitude towards procreation hinges on her educational and social status. An average pregnancy rate of 7 and an illiteracy rate of 75% accounts for the limited interest in contraceptive use in Benin. It appears, therefore, that people have not clearly grasped the importance of family planning. The key to birth spacing is to promote education, especially education of youth and women. Policymakers and opinion leaders have a big role to play in sensitizing the population to adjusting procreation to available resources, to curb irresponsible sex behavior, and to assure human development and potential. Thus, women in Benin will be able to free themselves from sociocultural constraints based on traditional values which do not always favor their full potential. This shift in attitude at the national level will curb child mortality, maternal mortality, malnutrition, preventable deaths, prostitution, sexually transmitted disease, and AIDS. Therefore, responsible family planning thrusts itself as one of the most effective and accessible methods to assure a quality life today and tomorrow. The Benin Association for the Promotion of the Family is open every day providing counseling and direction, loans for family planning services, and provision of contraceptive methods. Legal provisions, especially adoption of text popularizing family planning activities, contribute greatly to the success of all development partners in Benin intervening in the field of demographic planning. This act will mark a decisive turning point in the fight for economic, cultural, and social progress.

The authors are reporting results from rotavirus research in diarrhoeal stools among 220 children under 5 years of age in Cotonou C.N.H.U. (Bénin). Among them, 64 (29%) are rotavirus carriers.

During the studies on malaria chemoresistance, we noted great variations in parasite density of Plasmodium falciparum between screening in the morning and final selection in the afternoon, in asymptomatic people. To better understand this phenomenon, we conducted a study in october 1987 on primary school children in a village near the city of Bobo-Dioulasso, at the peak malaria prevalence. We performed 3 blood-smears at 8 a.m., 2 p.m. and 8 p.m., on Day 0 and Day 4, to an initial number of 86 children, aged from 6 to 9 years. By the end of the study 44 children remained who fulfilled the inclusion criteria Among them 35 showed a parasitaemia on Day 0 and 9 remained negative. On Day 4, 28 were positive and 16 remained negative. Of the 35 children positive at entry to the study 16 remained continuously positive, the others were negative on at least one occasion. Of the 28 children positive on Day 4, 14 remained continuously positive. For the 16 people with a parasitaemia continuously positive on Day 0.7 (43.7 p. cent) became spontaneously negative on Day 4. But considering the small size of our sample, the analysis of the nycthemeral variation and of the variation between the two days did not show a significant difference. Further studies involving a greater number of blood-smears during a longer period and concerning more people, should be conducted. The possibility of spontaneous negativation of the parasitaemia without drug absorption shows that there are some cases of false malaria chemosensitivity that are declared when the in vivo tests are not coupled with in vitro tests.

To define the clinical spectrum of loiasis more precisely and to begin to assess the immunologic basis for the difference in clinical manifestations between visitors to endemic areas and natives of these areas, 51 West African patients with loiasis were evaluated and compared with 42 infected expatriates. Microfilaremia was present in 90% and Calabar swellings in only 16% of the endemic patients. Conversely, only 10% of the expatriates were microfilaremic while 95% complained of Calabar swellings. The endemic population showed significantly decreased levels of peripheral blood eosinophils, parasite-specific IgG, and lymphocyte proliferation to parasite antigens compared with the nonendemic population. These findings support the hypothesis that differences in the modulation of the immune response to parasite antigen are responsible for the observed differences in clinical presentation between expatriate and endemic populations with loiasis.

In the coastal area of Benin, where chloroquine resistant Plasmodium falciparum strains occur, 152 children in the Guezo military camp (Cotonou) and 448 children in a fishermen village (Ekpe), on the southern bank of lake Nokoue, are examined. The falciparum malaria infected children (29 and 135 respectively) have received 35 mg/kg body weight of amodiaquine (Flavoquine) divided in three consecutive daily doses. Only one child among the 69 treated having a parasitemia higher than 1,000/mm3 failed to be cured. The amodiaquine tolerance is excellent for, respectively, 64% and 72% of the children. Minor side-effects are rapidly regressive. The frequency of conjonctival hyperhemia as an amodiaquine side-effect is nevertheless relatively high (14.7%) in the children regularly treated with this drug, e.g. those of the military camp, while it is rare (0.8%) in others, e.g. in the fishermen village children where amodiaquine is unusual as an antimalarial medicine.