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Littérature scientifique sur le sujet « Verità biologica »

Auteur : Grafiati
Publié le 10 mars 2023

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Articles de revues sur le sujet "Verità biologica"

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Belozorovich, Anna. « Volpi, farfalle, uccelli e un cagnolino nero : il mimetismo e la sopravvivenza sotto il regime staliniano in Vesti bianche di Vladimir Dudincev ». Altre Modernità, no 26 (29 novembre 2021) : 145–64. http://dx.doi.org/10.54103/2035-7680/16802.

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L’articolo prende in esame Vesti bianche (Belye odeždy), il secondo romanzo di Vladimir Dudincev (1918-1998), figura tragica della letteratura sovietica. Dopo Non si vive di solo pane (1957), riscuote un enorme successo ma viene costretto al silenzio a causa dello scandalo politico che ne deriva. Vesti bianche, scritto nel 1966, ma pubblicato solo vent’anni più tardi (1987), è ambientato nel pieno del lysenkoismo, la violenta repressione nei confronti della comunità scientifica che ebbe luogo tra gli anni ’40 e ’50. I suoi protagonisti sono biologi: comprendere la natura, essere in dialogo con il mondo naturale, è la loro prerogativa per ottenere dei risultati. La riflessione scientifica è puntualmente accompagnata da quella filosofica. In una intensa discussione sul rapporto tra l’uomo e la Natura, i protagonisti si schierano su differenti posizioni e sembrano “indossare” figure animali quasi con valore totemico. Le possibili configurazioni della società umana, i rapporti professionali e le esperienze individuali vengono messe in relazione con il comportamento animale. Il carattere associato a questi animali riporta sia al loro comportamento in natura sia alla simbologia ad essi legata nella tradizione popolare russa. La ricerca della verità da parte degli uomini di scienza incontra la necessità di mascheramento, parola chiave della trama. Il mimetismo è vissuto come un inganno necessario, come per mantenere la varietà biologica nel mondo naturale, così per garantire la libertà del pensiero e della ricerca scientifica in un paese paralizzato dal regime.
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Feng, Yue, Baosen Zhou, Zhen Wang, Guijuan Xu, Lili Wang, Tingting Zhang et Yanping Zhang. « Risk of Candida Infection and Serious Infections in Patients with Moderate-to-Severe Psoriasis Receiving Biologics : A Systematic Review and Meta-Analysis of Randomized Controlled Trials ». International Journal of Clinical Practice 2022 (21 septembre 2022) : 1–11. http://dx.doi.org/10.1155/2022/2442603.

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Background. Biological agents used to treat moderate-to-severe plaque psoriasis have been associated with Candida infection and other serious infections. It is, however, necessary to verify whether biologic agents increase the risk of Candida infection and serious infections and whether these risks vary among biologics. Methods. PubMed, EMBASE, and Cochrane Library were searched for eligible randomized controlled trials (RCTs) from their inception to December 2021. Results from individual RCT were pooled using Peto’s method with a fixed-effects model, and I2 was calculated to assess the heterogeneity. A Cochrane collaboration tool was used to examine bias risk, and Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) were used to assess the quality of evidence. Results. This study included 48 published articles with data from 52 RCTs involving 27297 participants. The anti-interleukin (IL)-17 agents (95% confidence interval (CI) = 1.54–3.45, P < 0.0001 ) and anti-IL-12/23 agents (95% CI = 1.69–3.83, P < 0.0001 ) were associated with an increased risk of Candida infection compared with placebos, but there was no difference in Candida infection risk between anti-IL-17 agents and tumor necrosis factor inhibitors (TNFi) (95% CI = 0.92–3.07, P = 0.09 ). There was no evidence that the biological agents increased the risk of serious infections in adult psoriasis (95% CI = 0.93–2.06, P = 0.11 ) or that the biologics differed in the risk of serious infections. Conclusions. Our results indicated that anti-IL-17 agents, especially secukinumab, were associated with the increased risk of Candida infection. The clinically used biological agents did not increase the risk of serious infections.
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Kroese, Dinant, Chanel Lau et Andre Wolterbeek. « Exploring the ZET as biological model to verify grouping of chemicals for DART ». Reproductive Toxicology 56 (août 2015) : 23. http://dx.doi.org/10.1016/j.reprotox.2015.07.051.

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Barragán, Jorge. « Hologram : Beyond Biological Aging ». Gerontology and Geriatric Medicine 8, no 5 (31 décembre 2022) : 1–4. http://dx.doi.org/10.24966/ggm-8662/100149.

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Spies, Maria. « DNA Repair : Trust but Verify ». Current Biology 23, no 3 (février 2013) : R115—R117. http://dx.doi.org/10.1016/j.cub.2012.12.019.

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Carvalho, Lídia Raquel de, Sheila Zambello de Pinho et Martha Maria Mischan. « Methods to verify parameter equality in nonlinear regression models ». Scientia Agricola 67, no 2 (avril 2010) : 218–22. http://dx.doi.org/10.1590/s0103-90162010000200014.

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In biologic experiments, in which growth curves are adjusted to sample data, treatments applied to the experimental material can affect the parameter estimates. In these cases the interest is to compare the growth functions, in order to distinguish treatments. Three methods that verify the equality of parameters in nonlinear regression models were compared: (i) developed by Carvalho in 1996, performing ANOVA on estimates of parameters of individual fits; (ii) suggested by Regazzi in 2003, using the likelihood ratio method; and (iii) constructing a pooled variance from individual variances. The parametric tests, F and Tukey, were employed when the parameter estimators were near to present the properties of linear model estimators, that is, unbiasedness, normal distribution and minimum variance. The first and second methods presented similar results, but the third method is simpler in calculations and uses all information contained in the original data.
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Migone, Paolo. « Una critica all'articolo di Manfred Pohlen "Il potere d'influenzamento dell'analista e la veritŕ del suo metodo" ». PSICOTERAPIA E SCIENZE UMANE, no 4 (décembre 2010) : 515–25. http://dx.doi.org/10.3280/pu2010-004005.

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Viene criticato l'articolo di Manfred Pohlen (2005) "Il potere d'influenzamento dell'analista e la veritŕ del suo metodo", pubblicato nel numero scorso di Psicoterapia e Scienze Umane (2010, XLIV, 3: 345-364). Alcune critiche sono le seguenti: il potere suggestivo della psicoanalisi, dimostrato anche empiricamente, era giŕ discusso da Freud e da autori successivi (si pensi ai fattori relazionali e identificatori, o al "transfert positivo irreprensibile"); una dicotomizzazione netta tra scienze naturali e scienze umane puň considerarsi datata; l'influenza del terapeuta nel guidare il paziente in senso prospettico era presente in Jung ed č stata ripresa dall'ermeneutica; la psicoanalisi come capace di attivare potenzialitŕ inespresse si sovrappone al concetto di autorealizzazione (self-actualizazion) di Rogers e in generale della psicoterapia umanistica; nella teoria dell'attaccamento di Bowlby non vi č un riduzionismo biologico ma un'enfasi sulle relazioni oggettuali; e cosě via.
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Cai, Yizhi, Brian Hartnett, Claes Gustafsson et Jean Peccoud. « A syntactic model to design and verify synthetic genetic constructs derived from standard biological parts ». Bioinformatics 23, no 20 (5 septembre 2007) : 2760–67. http://dx.doi.org/10.1093/bioinformatics/btm446.

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BAŞTUĞ, Gizem, Yasin Burak HAL, Gökhan BAKTEMUR, Mahmut YARAR, Ecem KARA et Hatıra TAŞKIN. « Effect of growing mixtures including different agricultural wastes on yield and quality of Pleurotus eryngii ». Mustafa Kemal Üniversitesi Tarım Bilimleri Dergisi 27, no 3 (1 décembre 2022) : 578–87. http://dx.doi.org/10.37908/mkutbd.1098660.

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Aims: In this study, it was aimed to determine the effects of different agricultural wastes on yield and quality of the Pleurotus eryngii culture, which has very limited production in Turkey.Methods and Results: Spawn of P. eryngii were inoculated to substrate mixtures; oak sawdust (K), 2 oak sawdust + 1 wheat bran (G1), 2 poplar sawdust + 1 wheat bran (G2), 2 wheat stalk + 1 wheat bran (G3), 1 oak sawdust + 1 poplar sawdust + 1 wheat bran (G4), 1 oak sawdust + 1 wheat stalk + 1 wheat bran (G5), 2 peanut shell + 1 wheat bran (G6), 2 corn cob + 1 wheat bran (G7), 2 vine pruning waste +1 wheat bran (G8), 1 peanut shell + 1 oak sawdust + 1 wheat bran (G9), 1 corn cob + 1 oak sawdust + 1 wheat bran (G10), 1 vine pruning waste +1 oak sawdust + 1 wheat bran (G11). As a result of the study, while the shortest mycelia development time was recorded in G6 and G9 with 17 days, the longest time was in G4 medium with 30 days. The highest and the lowest yield were obtained from G6 and G3 with 171.14 g kg-1 bag and 53.26 g kg-1 respectively. While the highest biological efficiency was found in G9 with 44.86%,the lowest value was recorded in G3 with 17.34%. Conclusions: In yield, biological efficiency and mycelia development time, G6 and G9 mediums were found to be better than the others. When considering the importance of yield, biological efficiency and mycelia development time for producers, the success of peanut shell in P. eryngii culture is noteworthy.Significance and Impact of the Study: When common peanut culture in the Çukurova Region of Türkiye is considered, it is an important result that the waste of this plant can be used in the mushroom cultivation.
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Keats, Jonathan J., Marta Chesi, W. Michael Kuehl et P. Leif Bergsagel. « A Simple and Reliable Method To Verify the Authenticity and Purity of Human Myeloma Cell Lines. » Blood 110, no 11 (16 novembre 2007) : 2485. http://dx.doi.org/10.1182/blood.v110.11.2485.2485.

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Abstract The availability of human myeloma cell lines (HMCLs) has drastically benefited out understanding of multiple myeloma (MM). They represent essential resources to the myeloma research community at large who use them to identify and more importantly validate oncogenic events in MM. Furthermore, they represent the front line tools in efforts to identify novel therapeutic agents for MM patients. However, the myeloma research community is not immune to problems of cell line contamination (mixed populations) or systemic errors where HMCLs are labeled incorrectly. As the community evolves towards the development of tailor medicine it is essential that our basic tools are both pure and correct. Otherwise, a potentially beneficial therapeutic agent designed for a specific patient subset maybe lost simply because of a simple laboratory mix-up at some point over the years. To that end we have developed a simple PCR based method that can be used to validate the purity and authenticity of HMCLs. First two reference collections of over 50 HMCL maintained at the NCI and Mayo Clinic Arizona were compared using microsatellite fingerprinting. This process identified several previously unnoticed discrepancies. First, in both labs several cell lines that reportedly originated from different patients had the same fingerprints. These include the following unexpected pairs; ANBL-6 and DP–6, CAG and ARP–1, KMS–11 and KMS–20, KMS–11 and KMS–21PE/BM, JIM3 and KPMM2. Second, both KP–6 and KAS6/1 showed a level of cross-contamination with ANBL–6. All of the discrepant cell lines were requested from the original contributor and those that were available were retested. After this step we had identified unique fingerprints for ANBL–6, DP–6, KMS–11, and KMS–20. Furthermore, pure populations of KP–6 and KAS6/1 were confirmed. However, CAG and ARP–1 still had an identical fingerprint. Since the use of microsatellite fingerprinting is an expensive task and the identification of cross-contamination is not very robust we set out to develop better method. We decided to use a simple qualitative PCR method, as the binomial presence or absence of a band makes the interpretation of the fingerprint extremely easy. Furthermore, the high sensitivity of a qualitative PCR can pick up a small amount of contamination in the culture that can be lost in microsatellite analysis. This method involves a multiplex PCR screen that simultaneously interrogates 10 regions of the human genome. The screen is divided into two reactions, one with a panel of highly polymorphic copy number variations (CNV) that are often completely absent in some individuals, and a second one based on known biologic events present in the cell lines. The integration of the results from the CNV and Biological Fingerprints will identify each HMCL as a unique entity. We validated the methodology by confirming that this qualitative screen could pick up the cross–contamination identified in the original KP–6 and KAS6/1 samples. As our understanding of myeloma increases and we strive to develop new therapies for specific biological entities it will be essential that groups confirm both the authenticity and purity of their test cultures. We hope that widespread use of this simple screening methodology will significantly improve the quality and reproducibility of assays carried out in labs around the world.
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Thèses sur le sujet "Verità biologica"

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Mendola, Angela. « L’unitarietà dello statuto successorio tra Favor Legitimitatis e verità biologica ». Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2466.

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2014 - 2015
La tesi di dottorato dal titolo “L’unitarietà dello statuto successorio tra favor legitimitatis e verità biologica” ha ripercorso, dal punto di vista storico-giuridico, la non facile relazione esistente tra filiazione in costanza di matrimonio e filiazione avvenuta al di fuori di esso, soprattutto in considerazione dei relativi profili successori. Sono state analizzate le novità introdotte dalla legge di riforma, recante “Disposizioni in materia di riconoscimento dei figli naturali”, L. n. 219/2012, e dal decreto legislativo di attuazione, n. 154/2013. In particolare, si è provveduto a rileggere criticamente quelle norme del libro II del codice civile che prevedevano un’anacronistica dicotomia, tanto formale, quanto sostanziale, tra “figli legittimi” e “figli naturali”. La ricerca ha preso le mosse dall’analisi dell’art. 2, co. I, lett. f, della precitata L. n. 219/2012, con cui il legislatore ha investito il Governo del compito di “assicurare l’adeguamento della disciplina delle successioni (…) al principio di unità dello stato di figlio (…)”. Successivamente, sono state analizzate tutte le norme del diritto successorio novellate per effetto del decreto legislativo di completamento della riforma della filiazione (D.Lgs. n. 154/2013), dal titolo “Revisione delle disposizioni vigenti in materia di filiazione, a norma dell’articolo 2 della legge 10 dicembre 2012, n. 219”. In prima istanza, si è compiuta una mera operazione di sistemazione linguistica, espungendo dagli artt. 467, 536, 538, 565, 566, 570, 573, 580, 581, 582, 583, 594, 715 e 737 c.c., le parole “legittimi” e “naturali”, optando per un semplice riferimento ai figli. Lo studio dello statuto successorio dei figli nati all’interno o al di fuori del matrimonio si è svolto ponendo lo sguardo anche agli altri ordinamenti giuridici europei. La ricerca ha posto come base di comparazione la disciplina successoria offerta dalle esperienze di civil law. Si pensi alla Ley 11/1981 spagnola, che ha provveduto ad adattare la normativa del codice civile a quella della Costituzione, nell’ottica della assoluta equiparazione tra figli. Una disamina è stata offerta anche con riguardo agli interventi del legislatore d’oltralpe, attraverso la legge 2001-1135, L. n. 2002-305, ancora per il tramite dell’Ordonnance n. 2005-759 e della legge n. 2009-61. Sono state, inoltre, esaminate le riforme tedesche del 1969, vale a dire la legge sui “figli non legittimi”, nichteheliche Kinder, e quella di riforma del diritto della filiazione del 1997 (KindRG). Sul fronte del common law, in tema di equiparazione tra tipi di filiazione, si è provveduto ad individuare, innanzitutto, il Family law Act del 1987, con cui è stata abolita anche la dicitura linguistica di illegitimate, ed il Children Act del 1989. [a cura dell'autore]
The doctoral thesis entitled “The unity of the Statute of succession between legitimitatis favor and biological truth” has retraced , from the point of historical and legal perspective , the difficult relationship between filiation in wedlock and filiation given outside of it , especially in view of its successors profiles . The changes introduced by the reform law were analyzed on “Measures regarding the recognition of illegitimate children” , Law no . 219/2012 , and the legislative decree implementing, n . 154/2013 . In particular , it was decided to critically review the provisions of Book II of the Civil Code which provided an anachronistic dichotomy, both formally, as a substantial, between “legitimate children” and “natural children”. The research was prompted by the analysis art. 2 , co . I, letter . f , of the aforementioned Law no . 219/2012 , in which the legislature has invested the government with the task of “ensuring the adaptation of the succession rules ( ... ) the principle of the child - state drives ( ... )”. Subsequently, were analyzed all the rules of succession novellate law by virtue of Legislative Decree completion of the reform of filiation (Legislative Decree . N . 154/2013) , entitled “Review of the current provisions of filiation , pursuant Article 2 of the law of 10 December 2012, n . 219”. In the first instance, it has accomplished a mere linguistic accommodation operation, expunging from Articles 467 , 536 , 538 , 565 , 566 , 570 , 573 , 580 , 581 , 582 , 583 , 594 , 715 and 737 of the Civil Code , the “legitimate” and the words “natural”, opting for a simple reference to the children. The study of the Statute of succession as children born within or outside marriage took place by placing the eye to other European legal systems. Research has set as a basis for comparing the discipline succession offered by civil law experience. Think of the Spanish Ley 11/1981, which has adapted the civil code legislation to that of the Constitution, in view of the absolute equality among children. An examination was also offered regarding the remediation of the legislature beyond the Alps, through law 2001-1135, L. n. 2002-305, again through Ordonnance n. 2005-759 and Law. 2009-61. It was also examined the German reform of 1969, namely the law on “no legitimate children”, nichteheliche Kinder, and that of the filiation of the 1997 law reform (KindRG). In terms of the common law, in terms of equivalence between types of filiation, steps were taken to identify, firstly, the Family law Act of 1987, which was also abolished the linguistic expression as illegitimate, and the Children Act 1989. [edited by author]
XIV n.s.
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Giunchedi, Diletta <1989&gt. « Le nuove forme di genitorialità tra vincoli biologici, verita legale e legami affettivi ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amsdottorato.unibo.it/9445/1/Tesi%20di%20Dottorato%20Diletta%20Giunchedi.pdf.

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Le recenti novelle e l’evoluzione delle tecniche riproduttive scientifiche hanno promosso un progressivo processo di frammentazione della figura genitoriale, che sino ad allora era considerata unitaria ed intimamente connessa all’incontro tra uomo e donna. A tale concezione unitaria del legame genitoriale corrispondeva la considerazione che la coincidenza tra vincolo genetico e verità legale fosse foriera del soddisfacimento del superiore interesse del minore. La genitorialità può ad oggi essere suddivisa tra genetica, qualora tra il genitore condivida con il figlio il medesimo patrimonio genetico; biologica, nell’accezione di gestazionale e dunque caratterizzante il rapporto tra madre e figlio; e sociale, qualora l’adulto, seppur in mancanza di un titolo legale e altrettanto di un legame di sangue con il figlio, adempie ai doveri di cura e di mantenimento propri dell’esercente la responsabilità genitoriale. A fronte della pluralità dei soggetti che latu senso possono essere considerati genitoriali in forza di una pluralità e eterogeneità di legami, l’interprete deve interrogarsi circa la effettività e la cogenza delle tradizioni definizioni di madre e di padre e soprattutto la resilienza dei criteri attributivi dello stato di filiazione.
The thesis aims to analyse the concept of parenthood, in consideration of social, scientific and statutory changes. The developments in reproductive medicine changed the way of thinking about the reproduction process. In particular, it is discussed which is the legally fair way for becoming parent(s) and for being parent(s) in itself. Legal concepts which had remained undisturbed for ages are now radically altered. Many laws regarding parenthood have been found to be inconsistent with the values arising from the more frequent reproductive and so the definition of mother. The recent statutes and the evolution of scientific reproductive techniques have promoted a progressive process of fragmentation of the parental figure, which, until then was, considered unitary and intimately linked to the encounter between man and woman. In the light of these changes, it is necessary to redefine an “untaught” (legal) concept of mother, since the intimate connection between the mother and her child through the gestational period is something connected with ‘nature’, and has never before needed to be clarified or even defined. There are three ways in which a person may be and become a parent of a child, and each of them is considered a “very significant factor” in the child’s welfare. The distinction lies in the distinguished concepts of genetic link, gestational/biological relationship and social or psychological relationship. The first one designates the parents who have generated the child, based a blood connection. Secondly, the gestational parenthood concerns conceiving and bearing the child. The third factor is the social parenthood, resulting from (the/a) day-to-day attention given to the child's needs for physical care, nourishment, comfort, affection, and stimulation.
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Lemerle, Sébastien. « In carne veritas ? : le biologisme comme phénomène éditorial en France, 1970-2000 ». Paris, EHESS, 2007. http://www.theses.fr/2007EHES0080.

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Depuis plusieurs décennies, se développent en France de nombreuses théories sociales inspirées par les sciences biologiques. À l'étude du champ éditorial, où cette situation est particulièrement visible, il apparaît toutefois que ce phénomène résulte davantage de l'action d'intermédiaires culturels désireux de diffuser de nouvelles conceptions du savoir et de modifier les hiérarchies intellectuelles, que d'une véritable révolution dans le domaine des sciences sociales. L'essor du biologisme s'appuie sur le prestige accumulé par les sciences biologiques depuis la fin de la Seconde Guerre mondiale, ainsi que sur l'émergence d'un nouveau type d'intellectuel, le « savant ». Il repose également sur l'apport du biologisme à la critique des « philosophies du soupçon », ainsi qu'à l'affirmation du « retour du sujet» dans les années 1980. Il se manifeste par la promotion d'une ingénierie sociale biopsychologique peu soucieuse des facteurs environnementaux (sociaux,géographiques, etc. )
Numerous social theories inspired by biological sciences have been developing in France for decades. If one takes a look at the publishing field, where this development is particularly obvious, it occurs that such a phenomenon is more the result of the action of cultural go-betweens desirous of diffusing new conceptions of knowledge and modifying intellectual hierarchies, than a true revolution among the social sciences. The growth of biologism relies on the prestige accumulated by biology since World War II, as well as on the emergence of a new kind of intellectual, the « scientist ». It also rests on the contribution of biologism to the criticisms levelled at 1960's critical theories, as well as to the discussions concerning the « return of the subject » in the 1980's. It is taking shape with the promotion of a biopsychological social engineering that does not pay much attention to environmental factors (social, geographical, etc. )
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Bole, Cyprien. « Etude ostéo-morphométrique des tortues marines de la super-famille des Chelonioidea ». Paris, Muséum national d'histoire naturelle, 2010. http://www.theses.fr/2010MNHN0021.

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La taxonomie de la super-famille des Chelonioidea (toutes les tortues marines actuelles, excepté la tortue luth) a beaucoup fluctué depuis sa création en 1811 par Oppel. Si de nombreuses études ont été réalisées, concernant d’une part la description de caractères qualitatifs et quantitatifs permettant de distinguer les espèces, et d’autre part le génome, aucune n’a été véritablement menée dans l’optique de quantifier les conformations géométriques du squelette et d’exposer leurs particularités. Les crânes, les mandibules et cinq os longs de 307 spécimens des collections du Chelonian Research Institute (USA) ont été numérisés à l’aide de trois méthodologies différentes de morphométrie géométrique : positionnement de points repères 2D, positionnement de points repères 3D et relevés de contours 3D. Pour tous les spécimens, nous connaissions l’espèce, le stade de développement, la provenance et le sexe. Ainsi, nous avons pu étudier la variabilité liée à ces quatre facteurs au sein de ces structures osseuses. La morphométrie géométrique permet de faire la synthèse, à l’échelle de précision souhaitée, de la géométrie d’un objet dans sa globalité. Elle bénéficie d’un fondement mathématique rigoureux qui garantit des statistiques robustes. Plusieurs champs d’analyses ont été développés et tout particulièrement au sein du genre Chelonia où nous avons estimé, comparé et visualisé la variabilité des individus de l’Atlantique ouest, de la région Indo-Pacifique et du Pacifique aux différents stades de développement. Ces populations présentent en effet des différences importantes au niveau de la géométrie de leur squelette pouvant expliquer en partie la fluctuation de la taxonomie du genre Chelonia et la discussion du paraphylétisme de Chelonia mydas. La géométrie de tous les os étudiés est différemment corrélée avec les facteurs retenus, excepté le sexe pour lequel la variabilité des conformations semble moins structurée. Ceci permet d’envisager de nombreuses applications pratiques : amélioration des connaissances générales de la biologie de ces reptiles (le suivi satellite étant très coûteux en raison des fortes mortalités naturelles et autres), mais aussi détermination de spécimens, voire de restes archéologiques de tortues marines qui aujourd’hui ne sont pas étudiés, bien qu’il soit fréquent d’en retrouver sur des sites littoraux de nombreuses régions du monde
The taxonomy of the super-family Chelonioidea (all the extant marine turtles except the leatherback) has changed many times since its creation in 1811 by Oppel. Today numerous studies have been carried out both on the descriptive characters (qualitative and quantitative) for distinguishing species and about their genomes. But none has really been devoted to quantifying the bone’s geometrical shape and conformations that should better their knowledge. The skulls, lower jaws and five long bones of 307 specimens belonging to the Chelonian Research Institute (USA) were digitized using three different geometric morphometrics methods: 2D landmarks, 3D landmarks, 3D outlines. For each specimen, we had information about the species, stage of development, origin and sex. We studied the shape variability related to these four factors in the bony structures. Geometric morphometrics allow to synthesis the global geometry of an object. It has a rigorous mathematical background and ensures robust statistics. We tested several hypotheses, especially among the genus Chelonia where we compared and visualized the shape variability of western Atlantic, Indo-Pacific and Pacific individuals, including the three stages of development. As these populations presented significant differences in the bony structure geometry, thus may partly explain the fluctuation of the taxonomy of the genus Chelonia and the discussion of the paraphyletism of the current species Chelonia mydas. The geometry of all the bones we studied was correlated with the different factors we tested, except for the sex for which the shape variability seems to be less structured. This allows to consider several practical applications: to improve the general knowledge of the biology of these reptiles (as satellite tracking is very expensive because of the high natural level of mortality), but also to make determinations of specimens or of archaeological sea turtles remains, which are fairly frequent
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Stokke, Bård Gunnar. « Coevolutionary adaptations in avian brood parasites and their hosts ». Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-161.

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Dette prosjektet har satt søkelyset på to problemstillinger knyttet til samevolusjonen mellom parasitt og vert; 1) utvikling av vertstilpasninger som mottrekk mot tilpasninger hos parasitten, med spesiell fokus på eggtilpasninger, og 2) mekanismer som kan forklare den store variasjonen i forsvarsatferd mot kullparasittisme blant ulike verter.

1) Flere gjøk- (Cuculus canorus) stammer eller gentes har utviklet egg som er veldig like vertens egne egg, såkalt eggmimikry, for å vanskeliggjøre vertenes eggavvisning. For å svare på dette har mange verter på sin side gjort det vanskeligere for parasitten ved å utvikle en lavere variasjon i utseende mellom sine egg innen kullet (innenkull-variasjon), og en høyere variasjon mellom egg fra kull til kull (mellomkull-variasjon). Mange nordamerikanske spurvefugler blir benyttet som verter av brunhodetrupialen (Molothrus ater), men denne parasitten har ikke utviklet eggmimikry i forhold til vertseggene. Vi sammenlignet kullvariasjonen mellom spurvefugler i Europa og Nord-Amerika og fant en høyere innenkull-variasjon og en lavere mellomkull-variasjon i eggutseende hos nordamerikanske spurvefugler, selv om forskjellen i innenkull-variasjon mellom kontinentene var mindre enn forventet.Hos europeiske spurvefugler er det i tidligere eksperimenter funnet at det er en sammenheng som forventet mellom avvisningsraten overfor parasittiske ikkemimikry egg og kullvariasjonen i eggutseende. Vi fant at det ikke var noen slik sammenheng hos spurvefugler i Nord-Amerika. Resultatene gir støtte til hypotesen om at parasitter med eggmimikry utøver et betydelig seleksjonstrykk for utvikling av bestemte eggkarakterer hos sine verter.

Vi undersøkte om det var noen forskjell i innenkull-variasjon hos avvisere og akseptorer av parasittegg innen bestemte populasjoner av tre europeiske spurvefugler; rørsanger (Acrocephalus scirpaceus), bokfink (Fringilla coelebs) og munk (Sylvia atricapilla). Det ble funnet at det var en signifikant forskjell i innenkull-variasjon i eggutseende mellom avvisere og akseptorer av kunstige ikke-mimikry gjøkegg i en rørsanger-populasjon i Tsjekkia; avviserne hadde en lavere innenkull variasjon enn akseptorer av slike egg. Denne vertspopulasjonen har en intermediær avvisningsrate overfor ikke-mimikry egg. Et tilsvarende forsøk ble utført hos en bokfink-populasjon i Norge og en munk-populasjon i Tsjekkia. Begge artene er meget gode avvisere av ikke-mimikry egg, noe som indikerer at de aller fleste individer er i stand til å avvise slike egg. Vi valgte derfor å benytte egg fra artsfrender i forsøkene med disse artene. I motsetning til hos rørsangeren fant vi at det ikke var noen forskjell i innenkullvariasjon mellom akseptorer og avvisere av fremmede egg hos bokfink og munk. Hos begge artene ble det funnet at avvisningen av fremmede egg i stor grad avhenger av kontrasten (grad av mimikry) mellom egne egg og parasittegget. Dette viser at selv om individene er i stand til å avvise parasittegg, så finnes det kognitive begrensninger som medfører at egg som utseendemessig ligger under en viss terskelverdi med hensyn til likhet med egne egg vil bli akseptert. Det ble ikke funnet noen indikasjoner på at avvisningsatferden var avhengig av vertenes alder eller av kondisjonelle stimuli for noen av de tre artene. Dette kan tyde på at det er en genetisk basert kobling mellom det å kunne gjenkjenne fremmede egg og innenkull-variasjon.

2) Mange vertsarter viser ingen eller kun intermediære avvisningsrater overfor fremmede ikke-mimikry egg. En slik tilsynelatende suboptimal atferd kan skyldes at det er kostnader forbundet med avvisningen som forhindrer evolusjon av perfekt avvisningsatferd. Slike kostnader kan være feilaktig avvisning av egne egg i uparasitterte reir (gjenkjenningsfeil), eller avvisning av egne egg i tillegg til parasittegget i parasitterte reir (avvisningskostnader). Hos gjøkverter, som ved suksessfull gjøkparasittisme har en reproduktiv suksess tilnærmet lik null, vil kun gjenkjenningsfeil være kilde til et potensielt seleksjonstrykk mot utvikling av høy avvisning av fremmede egg. Vi undersøkte om slike kostnader forekommer hos bokfink og munk; to arter som antas å ha blitt benyttet av gjøken tidligere, men som i dag ikke blir regelmessig parasittert. På grunn av at avvisningsatferden opprettholdes i fravær av parasittisme, forventet vi at disse artene begår få gjenkjenningsfeil.

Undersøkelsen gav støtte til denne prediksjonen; avvisningskostnader i parasitterte reir var relativt høye, men gjenkjenningsfeil i uparasitterte reir var meget sjeldent forekommende.

En hypotese ("spatiell habitat-struktur hypotesen") basert på metapopulasjonsdynamikk og med vekt på karakteristikker vedrørende vertsartenes hekkebiotop ble framsatt for å forklare de store variasjonene i avvisning hos europeiske spurvefugler. Hypotesen bygger på at gjøken benytter de verter som hekker nær utkikkspunkter for parasitten, dvs. nær trær. Arter som hekker både nær og langt fra trær er de beste gjøkvertene, i og med at genflyt fra uparasitterte populasjoner vil forhindre utvikling av perfekt avvisning i parasitterte populasjoner. Arter som alltid hekker nær trær har høye avvisningsrater fordi få eller ingen populasjoner har unnsluppet parasittering, og det har derfor vært sterk seleksjon for utvikling av vertsforsvar. Data for gjøkverter i Europa gav god støtte til hypotesen. Grad av parasitt eggmimikry og parasitteringsrater er høyest hos de vertsarter som kan hekke både langt fra trær og nær trær, noe som tyder på at gjøken har størst suksess hos slike arter.


This thesis deals with two topics in the coevolution between brood parasites and their hosts: 1) evolution of host adaptations against parasite egg mimicry, and 2) sources that could explain the considerable variation in rejection behaviour found among various passerines.

1) Several common cuckoo (Cuculus canorus) tribes or gentes in Europe have evolved eggs that are remarkably similar to the host eggs in both size and appearance (i.e. egg mimicry). To counter this adaptation in the parasite, hosts can produce eggs with similar appearance within clutches (low intraclutch variation) as well as eggs with diverging appearance between different clutches (high interclutch variation). Many North American passerines are utilised as hosts by the brown-headed cowbird (Molothrus ater). However, this parasite generally lays non-mimetic eggs. As predicted, we found that European passerines had a lower intraclutch variation and a higher interclutch variation in egg appearance than North American passerines.

However, the difference in intraclutch variation between the continents was less than expected. A relationship has previously been found among European passerines between the rejection rate of non-mimetic eggs and clutch variation in egg appearance, and this is thought to reflect the stage in the coevolution between parasite and host. We found no evidence of such patterns among North American species. These results provide support for the hypothesis that specific host clutch variation is a counteradaptation against parasite egg mimicry.

We investigated whether there was any difference in clutch variation between acceptors and rejecters of parasitic eggs within populations of three European passerines; reed warblers (Acrocephalus scirpaceus), chaffinches (Fringilla coelebs), and blackcaps (Sylvia atricapilla). In a Czech reed warbler population with an intermediate rejection rate of non-mimetic cuckoo eggs, it was found that rejecters had a statistically significant lower intraclutch variation than acceptors of such eggs. Age or conditional stimuli did not seem to have any influence on the rejectionbehaviour. A similar experiment was carried out in a Norwegian chaffinch population and a Czech blackcap population, which, however, were experimentally parasitised with foreign conspecific eggs because they are both very good rejecters of nonmimetic parasitic eggs. We found no difference in intraclutch variation among acceptors and rejecters of foreign eggs in chaffinches and blackcaps. However, it was found that the rejection of conspecific eggs greatly depends upon the contrast (i.e. mimicry) between the parasitic and their own eggs. It therefore seems that even though individuals have the ability to reject foreign eggs, limitations in their cognitive system entails that parasitic eggs that are too similar to the host eggs will be accepted. We also looked for potential effects of age on rejection behaviour and intraclutch variation, but no relationship between these variables was found. The results indicate that in these three species both rejection behaviour and clutch variation are more or less innate features, and also that there is a genetically based linkage between recognition of odd eggs and intraclutch variation in egg appearance.

2) Many hosts of brood parasites show no or only intermediate rejection rates of foreign non-mimetic eggs. Evolution of proper rejection behaviour could be prevented by costs related to egg rejection. Important in this respect are erroneous rejection of their own eggs in non-parasitised nests (recognition errors) and rejection of their own eggs in addition to the parasitic egg in parasitised clutches (rejection costs). Because successful cuckoo parasitism usually is detrimental to the breeding success of the host, only recognition errors are believed to be important as an opposing selective pressure against proper host defence in cuckoo hosts. We examined whether such costs exist in chaffinches and blackcaps. These species maintain a high rejection rate of foreign eggs, even though they are not currently used as hosts by the cuckoo. We therefore predicted that recognition errors should be absent or at least rare in these species. We found support for this prediction; rejection costs were relatively high but recognition errors were at best rare events.

In another investigation, we proposed a hypothesis (the "spatial habitat structure hypothesis") based upon metapopulation dynamics and characteristics concerning host breeding habitats to explain the variation in rejection behaviour found among European passerines. This hypothesis is based upon the fact that the cuckoo, as well as other avian brood parasites, needs access to vantage points in trees to monitor host nests, and thus only species breeding near trees are available as hosts. Our results were very much in accordance with this hypothesis. Species that breed both near and far away from trees are the best cuckoo hosts, because gene flow from non-parasitised populations breeding far from trees will prevent the evolution of proper rejection behaviour in parasitised populations breeding near trees. However, species that always breed near trees have high rejection rates because the majority of the populations have been utilised as hosts, and thus there has been a strong selection for the evolution of host defences. Furthermore, the level of parasite egg mimicry and the level of parasitism was found to be highest among hosts breeding both near and far away from trees, indicating that the cuckoo is most successful when utilising such species as hosts.


Paper VI is not included as a paper in this thesis, but is included as the introduction.
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Gagnon, Karine. « Dissémination et établissement de l'algue verte envahissante Codium fragile dans les herbiers marins ». Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27097/27097.pdf.

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Ouedraogo, Moussa. « Etude du rôle de la boucle C-terminale des récepteurs NPY Y1 et Y2 : Couplage biologique et séquences de régulation du trafic intracellulaire des récepteurs ». Université Louis Pasteur (Strasbourg) (1971-2008), 2006. http://www.theses.fr/2006STR13031.

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Le neuropeptide Y est une neurohormone impliquée dans de nombreuses fonctions physiologiques et états pathologiques. Il active différents récepteurs Y1, Y2, Y4 et Y5, tous couplés négativement à l'adénylyl cyclase via la protéine Gi/o. Les mécanismes de régulation de l'activation de ces récepteurs sont très peu documentés. Le laboratoire a montré que le récepteur Y1 est internalisé et recyclé à la membrane en réponse à l'activation par l'agoniste. Ceci n'est pas observé pour les récepteurs Y2, Y4, Y5. Il est alors d'un apport fondamental de comprendre les bases structurales de l'internalisation rapide du récepteur Y1 notamment à travers l'évaluation de l'importance de la boucle C-terminale dans la signalisation et le processus d'endocytose. Nous avons généré des récepteurs par mutation ponctuelle ou troncations progressives du domaine C-terminale de Y1 et des chimères par l'échange du domaine C-terminal entre les récepteurs Y1 et Y2. Ces récepteurs sont tous fusionnés à l'EGFP à l'extrémité N-terminale. Ils ont été transfectés dans des cellules HEK293. Nous avons ensuite caractérisé la fonctionnalité et analysé le profil de trafic intracellulaire des récepteurs. Nos résultats montrent que la boucle C-terminale du récepteur Y1 est critique pour l'endocytose du récepteur stimulé par l’agoniste mais n'est pas indispensable à son couplage à l’adénylyl cyclase et à sa désensibilisation. L'endocytose du récepteur Y1 stimulé par l’agoniste est sous le contrôle de deux motifs localisés sur les boucles C-terminale et i2. Le récepteur Y2 qui n’est pas internalisé dans les mêmes conditions possède uniquement le motif présent dans le domaine C-terminal. Par ailleurs, la troncation des 27 ou 32 derniers acides aminés du domaine C-terminal a permis de mettre en évidence une internalisation constitutive du récepteur qui est inexistante sur le récepteur Y1 natif. Elle serait due au motif consensus YXX démasqué par la troncation et/ou au changement conformationnel du récepteur
Neuropeptide (NPY) is a neurohormone involved in many physiological functions and pathophysiological states. NPY activates various receptors Y1, Y2, Y4 and Y5. All are seven transmembrane domains receptors negatively coupled to the adenylyl cyclase via a Gi/o protein. The regulation of the activity of NPY receptors is not well documented. Recent study in the laboratory showed that the Y1 receptor is internalized and recycled to cell membrane upon agonist stimulation. Surprisingly, we did not observe internalization of the other Y2, Y4, Y5 receptors under the same conditions. It is therefore crucial to understand structural bases of the rapid internalization of the Y1 receptors by evaluating the importance of the C-terminal loop in the process of receptor endocytosis. To do so, we generated receptors punctually mutated or progressively deleted amino acids from its C-terminal tail and chimeric receptors resulting from the exchange of C-terminal tails between Y1 and Y2 receptors. All constructs were coupled to the EGFP in N-terminal and transfected in HEK 293 cells. We thereafter checked their functionality and analyzed the intracellular profile of receptors trafficking. Data showed that the C-terminal tail of the Y1 receptor is critical for receptor internalization mediated by the NPY but neither essential to its coupling with the adenylyl cyclase nor the receptor desensitization. The internalization induced by the agonist requires the presence of two motifs located on the C-terminal domain and i2 loop of the Y1 receptor. The Y2 receptor which is not internalized present only one of them localized in the C-terminal domain. In addition, deletion of the 27 or the last 32 amino acids of the C-terminal tail showed a constitutive endocytosis of the receptor which is not present in wild-type Y1 receptor. This tonic regulation of the truncated receptors would be due to the consensus motif YXX uncovered by truncation and/or to a conformational change of the receptor
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Dufrénoy, Pierrick. « Valorisation en synthèse organique d'éco-catalyseurs hétérogènes régénérables à partir de matériaux verts cultivés sur des sols contaminés ». Thesis, Normandie, 2018. http://www.theses.fr/2018NORMLH30/document.

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Les activités des anciennes industries métallurgiques spécialisées dans la production et la transformation de plomb, de zinc ou d’autres métaux ont engendré une pollution métallique importante des sols selon la localisation de ces derniers. Des études actuelles proposent ainsi des solutions de requalification de ces sols via des processus de phytoremédiation afin de valoriser au maximum les plantes cultivées sur ces sols contaminés. Ce projet de thèse a ainsi été réalisé dans le but de valoriser des écocatalyseurs hétérogènes régénérables. Ces derniers sont obtenus à partir des plantes cultivées sur des sols contaminés dans la synthèse organique pour la production de composés à haute valeur ajoutée. Les sols contaminés utilisés dans ce projet proviennent de la région Hauts-de-France (Auby et Noyelles-Godault). Dans cette optique, quatre types de réactions ont été testés pour valider l’efficacité et la recyclabilité des écocatalyseurs : La réaction d’aminolyse, La réaction de Friedel-Crafts, La transformation d’aza-Michael, et enfin La réaction de transestérificationDes écocatalyseurs riches en zinc (EcoZn), obtenus à partir de la biomasse végétale de ray-grass (Lolium perenne L.), ont été caractérisés par des méthodes physico-chimiques puis validités leurs critères d’efficacité et de recyclabilité. Ceux-ci ont ainsi permis de synthétiser plusieurs séries de composés à activité anti-inflammatoires connus (piroxicam, méloxicam, idrocilamide) et de nouveaux, des inhibiteurs de la farnésyltransférase (à visée anticancéreuse ou pour combattre des maladies orphelines telles que la progéria) ou encore de découvrir un nouvel accepteur d’aza-Michael
The activities of the former metallurgy industries specialized in the production and processing of lead, zinc or other metals have resulted in significant metallic pollution of soils depending on their location. Current studies propose solutions for the requalification of these soils through the phytoremediation processes in order to maximize the value of plants grown on these contaminated soils. This PhD thesis project was thus realized with the aim of valorizing regenerative heterogeneous ecocatalysts. The latter were obtained from the plants cultivated on contaminated soils in organic synthesis for the production of high value added molecules. The contaminated soils used in this project came from the Hauts-de-France region (Auby and Noyelles-Godault). In this light, four types of reactions have been tested to validate the efficiency and recyclability of ecocatalysts: The aminolysis reaction The Friedel-Crafts reaction The aza-Michael transformation The transesterification reactionThe zinc-rich ecocatalysts (EcoZn), obtained from the plant biomass of ryegrass (Lolium perenne L.), were characterized by physicochemical methods and validated their efficiency and recyclability criteria. The latter were successfully used to reach various series of compounds with anti-inflammatory activity known (piroxicam, meloxicam, idrocilamide) and new, inhibitors of farnesyltransferase (for anticancer purpose or to fight orphan diseases such as progeria) or to discover a new aza-Michael acceptor
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Niez, Benjamin. « Acclimatation de l'arbre aux flexions répétées et conséquences sur le comportement mécanique et les propriétés hydrauliques du bois vert : Biologie végétale ». Thesis, Université Clermont Auvergne‎ (2017-2020), 2018. http://www.theses.fr/2018CLFAC046/document.

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Les arbres, enracinés au sol, adaptent leur développement à leur environnement fluctuant et en particulier aux conditions mécaniques imposées en permanence par le vent. Les tempêtes des dernières décennies ont mis en lumière le rôle majeur, pour la survie à long-terme des arbres, du processus d’acclimatation aux contraintes mécaniques dues au vent. Au premier ordre, le vent exerce principalement des efforts de flexion répétés sur les branches et tiges des arbres qui tendent à osciller pendant les épisodes venteux. Ces flexions entrainent une modification de la croissance des arbres en hauteur, en diamètre ou au niveau du système racinaire mais également la formation d’un bois à l’anatomie et aux propriétés particulières ; lequel est désigné par le terme « bois de flexion ». Au cours de ces travaux de thèse, nous avons développé des dispositifs expérimentaux originaux nous permettant, d’une part, d’appliquer des traitements de flexions unidirectionnelles répétées sur des tiges de jeunes peupliers, en contrôlant l’amplitude des déformations appliquées à la tige, et d’autre part, de contrôler différents niveaux de stress hydrique. Les suivis de croissance pendant une saison de végétation complète ont montré que l’acclimatation mécanique des arbres est un processus qui, bien que très couteux en matière de construction de biomasse, s’avère primordial et se met en place même lors de conditions de stress hydrique sévère. De plus, nous avons pu démontrer que l’augmentation de biomasse liée à cette acclimatation s’effectue principalement dans les zones où les déformations tissulaires sont les plus fortes ; conduisant ainsi à des géométries de sections particulières qui accroissent considérablement la rigidité de flexion des tiges. Une modélisation mécanique par éléments finis a aussi permis de révéler que ces configurations issues de l’acclimatation conduisent à une meilleure répartition des contraintes mécaniques, en abaissant en particulier l’intensité des contraintes maximales de compression subies par le bois. Afin de descendre dans les échelles spatiales, nous avons développé des outils et des méthodes de caractérisation originaux qui ont permis de mesurer, au niveau tissulaire, l’impact des différents types de sollicitations (compression et/ou traction répétées), engendrées au cours d’une flexion de tige, sur les propriétés hydrauliques et mécaniques du bois vert ; tant du point de vue des propriétés usuelles (comportement élastique, conduction hydraulique) que du point de vue des fonctions de sécurité (rupture, sensibilité à la cavitation, …). Nous avons alors pu mettre en évidence le comportement singulier du bois formé sous sollicitations de compressions répétées qui montre en particulier une nette augmentation de sa capacité à subir des déformations importantes avec un endommagement très réduit. L’ensemble des résultats expérimentaux et de modélisation aux échelles tissulaires comme de l’organe entier, indique que les acclimatations de la croissance secondaire et des propriétés intrinsèques du matériau bois procurent un bénéfice mécanique pour la pérennité de l’arbre dans son environnement venteux fluctuant
Trees, anchored in the ground, adjust their development to their fluctuating environment and particularly to the mechanical conditions daily imposed by wind. Storms of last decades enlightened that acclimation of trees to mechanical stresses due to wind is a vital requirement for their long-term survival. Wind mainly leads to repeated bending of the branches and stems of trees that swing during windy events. These bending cause a modulation of trees growth in height, in diameter or at the level of the root system but also imply the formation of a wood with specific anatomy and properties; this wood was defined as “Flexure wood”. In our work, we developed original experimental setups in order to apply a treatment of repeated unidirectional bending to the stem of young poplars, while controlling the magnitude of the strains applied to the stem. The setup controlled different levels of hydric stress too. The monitoring of the growth during a growing season showed that the mechanical acclimation is a process that, although costly in terms of biomass construction, turns out to be essential and takes place even under severe hydric stress. Besides, we demonstrated that the increase of biomass, linked to this acclimation, is mainly provided in the areas where tissue strains are the highest; leading to specific cross-section geometries that considerably increase the stem bending rigidity. A mechanical modelling using Finite Elements also enlightens that these configurations, due to acclimation, lead to a better distribution of mechanical stresses, especially by decreasing the intensity of maximal compressive stresses endured by wood. In order to investigate the microscopic scale, original experimental devices were developed at the tissue scale to measure the effect of different mechanical stresses (repeated compression and/or tension), applied by stem bending, on the hydraulic and mechanical properties of green wood; as much in terms of usual properties (elastic behaviour, hydraulic conduction) as in terms of security functions (rupture, sensibility to cavitation, …). Thus, we enlighten the specific behaviour of wood formed under repeated compressive stresses that shows a significant increase of its ability to withstand high levels of strains with a very reduced damaging. The whole experimental and modelling results, as much at the tissue scale as at the tree scale, points out that the acclimations of secondary growth and wood properties provide a mechanical benefit for tree sustainability in its fluctuating windy environment
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Carpentier, Emilie. « EP1 et PME1 : deux protéines pariétales à motif RGD, quels rôles chez le lin ? » Rouen, 2005. http://www.theses.fr/2005ROUES025.

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Chez les animaux, l'adhérence cellulaire dépend d'interactions intégrines/protéines de matrice extracellulaire via un motif RGD. Chez les plantes, les mécanismes d'adhérence sont méconnus, bien que certaines protéines possèdent le motif RGD. Nous avons caractérisé 2 protéines pariétales de lin possédant ce motif. La première, une pectine méthylestérase (PME), catalyse la dé-méthylation des pectines. PME1 est maturée au cours de sa sécrétion et une fois mise en place dans la paroi de cals la surexprimant. Son pro-peptide n'a pas d'impact sur sa localisation. La seconde, EP1, glycoprotéine homologue aux Extracellular Protein, présente des similarités avec les lectines à mannose dans sa région N-terminale. In vitro, EP1 recombinante permet l'adhérence de cellules animales sans qu'elles forment de pseudopodes. De plus, la régulation positive de son expression par l'acide salicylique implique cette protéine dans la réponse aux pathogènes
In animals, cellular adhesion was widely studied, particularly interactions between integrins and extracellular matrix proteins, via the RGD motif. In plants, mechanisms involved in adhesion are still unknown, although some proteins contain a RGD motif. We characterized 2 flax cell wall proteins with this motif. The first one, a pectin methylesterase (PME) catalyzes the pectin de-methylation. PME1 is matured during its secretion and after its deposition in wall of callus overexpressing this protein. Its pro-peptide has no impact on its cell wall localization. The second one EP1, glycoprotein homologous to the Extracellular Protein shares, in N-terminal region, similarities with mannose lectins. In vitro, recombinant EP1 allows cells to adhere but not to spread like they do with adhesion proteins as fibronectin. Finally, the positive regulation of its expression by salicylic acid suggests that this protein is involved in the pathogen response
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Livres sur le sujet "Verità biologica"

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Capanna, E. Il tempo e la verità : Una breve storia della biologia. Roma : Casa editrice Università La Sapienza, 2006.

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Mantovani, Ferrando, et Ugo Ricci. La prova del DNA per la ricerca della verità : Aspetti giuridici, biologici e probabilistici. Milano : Giuffrè, 2006.

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Johnson, Art. Results of sampling to verify 303(d) metals listings for selected Washington State rivers and creeks. Olympia, Washington : Washington State Department of Ecology, 2002.

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Roose, Morgan. Results of sampling to verify 303(d) listings for chemical contaminants in shellfish from Dyes Inlet and Port Washington Narrows. Olympia, Wash : Environmental Assessment Program, 2002.

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Santos, Daniela Copetti, Josiane Fiss Lopes, Cátia Roberta de Souza Schernn, Juliane Ditz Knob, Fabiani Machado, Larissa Lunardi, Giustina Luisa Rozek Sirena, Maiara Ilisa Fauth, Juliane Oberoffer Santos da Rosa et Francieli Anelise Schmidt. Guia ilustrativo de sinais em Libras para o ensino de Biologia. Brazil Publishing, 2021. http://dx.doi.org/10.31012/978-65-5016-357-0.

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The use of LIBRAS (Brazilian Sign Language) during the classes helps in the learning of deaf students. By creating an illustrative Handbook we seek to facilitate the learning of the deaf student and advise teachers in the area of Biological Sciences. After the preparation of this material we verify how essential it is that other students have access to it, seeking to disseminate it.
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Haghi, A. K., et Ravindra S. Shinde. Modern Green Chemistry and Heterocyclic Compounds : Molecular Design, Synthesis, and Biological Evaluation. Apple Academic Press, Incorporated, 2020.

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Haghi, A. K., et Ravindra S. Shinde. Modern Green Chemistry and Heterocyclic Compounds : Molecular Design, Synthesis, and Biological Evaluation. Apple Academic Press, Incorporated, 2020.

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Haghi, A. K., et Ravindra S. Shinde. Modern Green Chemistry and Heterocyclic Compounds : Molecular Design, Synthesis, and Biological Evaluation. Apple Academic Press, Incorporated, 2020.

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Haghi, A. K., et Ravindra S. Shinde. Modern Green Chemistry and Heterocyclic Compounds : Molecular Design, Synthesis, and Biological Evaluation. Apple Academic Press, Incorporated, 2020.

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Modern Green Chemistry and Heterocyclic Compounds : Molecular Design, Synthesis, and Biological Evaluation. Apple Academic Press, Incorporated, 2020.

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Chapitres de livres sur le sujet "Verità biologica"

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Ramalakshmi, N., S. Arunkumar et Sakthivel Balasubramaniyan. « QSAR and Lead Optimization ». Dans Advances in Medical Technologies and Clinical Practice, 80–100. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-7326-5.ch004.

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There are many diseases for which suitable drugs have not been identified. As the population increases and the environment gets polluted, new infections are reported. Random screening of synthesized compounds for biological activity is time consuming. QSAR has a prominent role in drug design and optimization. It is derived from the correlation between the physicochemical properties and biological activity. QSAR equations are generated using statistical methods like regression analysis and genetic function approximation. Both 2D parameters and 3D parameters are involved in generating the equation. Among several QSAR equations generated, the best ones are selected based on statistical parameters. Validation techniques usually verify the predictive power of generated QSAR equations. Once the developed QSAR model is validated to be good, the results of that model may be applied to predict the biological activity of newer analogues. This chapter illustrates the various steps in QSAR and describes the significance of statistical parameters and software used in QSAR.
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Torrecillas Paula Lico, Diego. « The Biological and Structural Organization of the Squid Brain ». Dans Animal Models and Experimental Research in Medicine [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.107217.

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Marine invertebrate models (squid, sepia, and octopus) made important contributions to description mammals’ nervous system. Being a very simple nervous system relatively easy to be manipulated experimentally and visualized by simple microscope or magnifying glass, the giant synapses at stellate ganglion and the large synaptosomes prepared from the squid photoreceptor neurons served as an attractive model to Histology and Anatomy studies. This sophisticated nervous system has elucidated synaptic transmission in detail with their numerous proteins at presynaptic terminal, synaptic vesicle biogenesis, neurotransmitter secretion, vesicle recycling and, allowed the study of postsynaptic complex with their membranes receptors. However, there are few studies with biochemical and molecular approaches, which lead to a better understanding of their physiological functions and verify operation of such nervous system.
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Cabral-Miramontes, Juan, Pamela Dorantes-Alvarado et Elva Aréchiga-Carvajal. « Standard Analytical Techniques and de novo Proposals for Successfull Soil Biodegradation Process Proposals ». Dans Biodegradation - New Insights [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.109861.

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The contamination of water, air, and soil represent a serious problem worldwide. Therefore, it is a priority to reduce the levels of cytotoxic in the environment caused by human activities that generate chronic degenerative diseases. For example, soil contamination caused by oil and derivatives removed with biotechnological products based on biological systems of microorganisms with physiological and molecular mechanisms that allow them to carry out effective bioremediation processes, reducing the concentration of polluting hydrocarbons. The main obstacle is validating the biodegradation efficiency of chemical compounds by bacterial consortia; therefore, it is vital to adapt or develop analytical strategies to verify heavy-end reduction for each type of biological system used in remediation. This chapter describes the techniques and their adaptations for oil degradation and their derivatives promoted by microorganisms. As the limits of the methods vary within the parameters determined by international norms and laws, we compare conventional and new-generation proposals to adjust to probe biotechnological products based on consortia of biodiverse microorganisms that significantly degrade petroleum fractions.
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Kamal, Md Sarwar, Mohammad Ibrahim Khan, Kaushik Dev, Linkon Chowdhury et Nilanjan Dey. « An Optimized Graph-Based Metagenomic Gene Classification Approach ». Dans Data Analytics in Medicine, 1168–92. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1204-3.ch059.

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Biological interaction mainly depends on the interactions of various genes and genomes. To identify actual meaning of interactions we have to find out the facts and reasons for these interactions. Gene analysis allows to verify such environment. Gene annotation means to identify the exon regions in metagenomic samples. The de Bruijn graph plays significant role in gene prediction and next generation sequencing (NGS). Apart from that, Eular Path of de Bruijn graph introduced generalized gene annotation for translational and splicing signals, exon introns separation and coding regions. set of graph reduction rules have used to build a de Bruijn graph. Accurate solution for large scale sequencing, trims space complexity and generates optimal gene annotation have tested.
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Scott, Daniel. « Animal models of psychosis ». Dans Psychotic Disorders, sous la direction de Stefan Leucht, Andrea Cipriani et Toshi A. Furukawa, 496–506. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780190653279.003.0055.

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The creation of a valid animal model is of crucial importance to the study of the biological mechanisms underlying disease pathophysiology. This becomes difficult when studying psychiatric illness, most especially psychosis, as humans’ mental state is a strictly internally experienced phenomenon, and thus the biological readout of these conditions is often a behavioral assessment. Therefore, when designing appropriate animal model systems and behavioral assessments for the study of psychiatric illness, it is necessary that appropriate measures be taken to ensure the systems and tasks used fulfill rigorous demands of validity. This chapter discusses different forms of validity, expanding on the classical validity measures of face, predictive, and construct validity. Specific examples of behavioral assessments and animal preparations that adhere to these specific definitions of validity are presented. These include specific experimental paradigms that can be similarly assessed in humans with psychosis and animal models, methods to create an animal preparation based on known psychosis triggers and risk factors, and pharmacological means to demonstrate relevance to the human condition. The chapter argues for a systematic approach to design, verify, and validate an animal model system for research into psychosis specifically, and other psychiatric disorders more generally, based on these different classes of validity.
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Basit, S. Asif. « Artificial Intelligence in Business Processes ». Dans Handbook of Research on Digital Transformation, Industry Use Cases, and the Impact of Disruptive Technologies, 205–30. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-7712-7.ch012.

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The aim of this chapter is to establish that the principles used by neural networks can be applied to business process management. The similarity between artificial neurons and business processes, and hence between neural networks and process landscapes, will be demonstrated. This novel approach leads to an emphasis on process interactions and their effect on actions as a major governing factor in controlling process outputs. Stigmergic interaction in biological systems is explored in the context of business processes, and its potential to understand process interaction is investigated. In order to verify the use of stigmergy in business environments, a pilot study is described in which shop floor business processes in a retailing environment are observed and described using a stigmergic framework. Establishing the viability of using stigmergic interaction to control process actions and outputs is the first step towards designing neural process networks.
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Hamouda, Ragaa A., Nada M. Doleib et Muhammad A. Abuelmagd. « Scaling Up and Harvesting of Algae ». Dans Handbook of Research on Algae as a Sustainable Solution for Food, Energy, and the Environment, 197–227. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-2438-4.ch008.

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The scaling up and increment of the algal cultures cultivation process is a complex task that requires experienced staff. Some parameters such as biomass yield, biomass productivity, and specific growth should be calculated using the findings of laboratory scale that might be relevant for large-scale production as it provides a baseline to visualize and to verify production balance-related problems in the algal production system. The main goal of scale-up is to increase the production quantities with comparable or higher productivity and product quality. The harvesting process of the algal biomass represents a major hindrance in microalgae industry as it is approximately ranged from 20 to 30% of the total cost of the cultivation. There are many harvesting techniques such as physical, chemical, biological methods, and magnetic particle facilitated separation. This chapter has summarized the research progress in algal scaling up by optimizing different parameters such as light, temperature, nutrients, and strain selection.
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Ang, Li-Minn, Kah Phooi Seng et Christopher Wing Hong Ngau. « Biologically Inspired Components in Embedded Vision Systems ». Dans Computer Vision, 458–93. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-5204-8.ch018.

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Biological vision components like visual attention (VA) algorithms aim to mimic the mechanism of the human vision system. Often VA algorithms are complex and require high computational and memory requirements to be realized. In biologically-inspired vision and embedded systems, the computational capacity and memory resources are of a primary concern. This paper presents a discussion for implementing VA algorithms in embedded vision systems in a resource constrained environment. The authors survey various types of VA algorithms and identify potential techniques which can be implemented in embedded vision systems. Then, they propose a low complexity and low memory VA model based on a well-established mainstream VA model. The proposed model addresses critical factors in terms of algorithm complexity, memory requirements, computational speed, and salience prediction performance to ensure the reliability of the VA in a resource constrained environment. Finally a custom softcore microprocessor-based hardware implementation on a Field-Programmable Gate Array (FPGA) is used to verify the implementation feasibility of the presented model.
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Smith, Alexandra K. « Imaging Nanostucture ». Dans Edible Nanostructures, 210–29. The Royal Society of Chemistry, 2014. http://dx.doi.org/10.1039/bk9781849738958-00210.

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Food structure is based on a system of molecules that provide form and function. A better understanding of the arrangement of the underlying molecules that contribute to the macromolecular structure of natural foods leads to the ability to create novel food products. Microscopes give us the opportunity to image the basic architectural molecules and are tools that contribute to research into food structure. Imaging of food at a nanostructure level is possible by the use of the transmission electron microscope, the scanning electron microscope, and the atomic force microscope. The ability of these instruments to provide nanostructure resolution is based on design principles, and the quality of the preparation of the sample. The critical objective of sample preparation is to maintain the original properties of the biological material, whether it is native tissue or a complex emulsion. Only when the sample is prepared without distortion can the interpretation be considered valid. The researcher must understand the opportunities and limitations that come with each imaging method. Cryo-preparation methods are preferred for food imaging applications because freezing preserves water, fat, and air and the distribution of these constituents, which are major components in most food systems. Imaging methods must be complemented with other scientific methods to verify interpretation and eliminate bias. Correlated microscopy techniques are recommended.
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« Aquatic Stewardship Education in Theory and Practice ». Dans Aquatic Stewardship Education in Theory and Practice, sous la direction de Amy Grack Nelson et Jenifer Matthees. American Fisheries Society, 2007. http://dx.doi.org/10.47886/9781888569902.ch4.

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<i>Abstract</i>.—MinnAqua, a program of the Minnesota Department of Natural Resources’ (DNR) Division of Fish and Wildlife, educates the state’s youth about angling and aquatic resources. In 2001, MinnAqua began developing a leaders’ guide so educators could carry out MinnAqua activities in their own setting. As part of the development process, a formative evaluation was undertaken to answer two questions: (a) to what extent are MinnAqua’s rewrite guidelines addressed in individual lessons and the leaders’ guide as a whole?, and (b) to what extent does the leaders’ guide meet the educational needs of intended users in both formal and informal education settings? Evaluative feedback was gathered from a variety of individuals over two stages of data collection, with revisions occurring after each stage. During stage one, formal and informal educators pilot tested lessons in their respective educational settings and provided input through surveys, critiques, and focus groups. DNR Fisheries staff also critiqued lessons to ensure the scientific accuracy of the biological information. Stage two involved instructional design experts verifying educational content in the lessons, educational outreach partners commenting on how the leaders’ guide could be used to support their outreach efforts, and an accessibility expert determining how to adapt MinnAqua lessons for use with individuals with physical disabilities. The evaluation results were used to verify the incorporation of the rewrite guidelines, identify ways to strengthen the extent to which the guidelines were addressed, and modify the leaders’ guide to more fully meet educators’ needs.
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Actes de conférences sur le sujet "Verità biologica"

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Piovesan, Davide, et Michael J. Panza. « A Dissipative String Model for Human Tendons ». Dans ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-34304.

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This work presents an analytical modelling of a tendon driven system. We modelled the tendon as a continuum string using physiologically plausible value for the intrinsic characteristics of biological tissues to verify the system’s stability. We used Poincare’s sections to verify the types of attractors the system has and proved that the system is non-chaotic in a large range of physiologically plausible excitation frequencies. This work is relevant for understanding the control of force and movement as a function of the muscle contraction. Wide applications can also be found as a guideline for the design of artificial muscles and cable driven robots.
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Edelmann, Martin, Thomas Meier, Markus Rupp et Kathia Vilpoux. « Laser induced temperature distribution in cell layers ». Dans European Conference on Biomedical Optics. Washington, D.C. : Optica Publishing Group, 2001. http://dx.doi.org/10.1364/ecbo.2001.4433_10.

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Thermal stimulation of single cells and cell layers is used for investigations of temperature associated processes like necrosis or apoptosis. Simulations of temperature distributions in layered structures on various substrates are presented. In order to verify the simulations a diode pumped IR-cw laser system was developed. The TEM00 output beam at a wavelength of 2.8 µm was focused on biological material to compare visible effects with the calculations.
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Elcin, Huseyn. « FUNCTION AND SAFETY EVALUATION OF 3D TECHNOLOGY TO PREPARE BONE REPAIR BIOMATERIALS ». Dans International Trends in Science and Technology. RS Global Sp. z O.O., 2021. http://dx.doi.org/10.31435/rsglobal_conf/28022021/7433.

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PLGA/HA composite biomaterials are prepared, and 3D printing technology is used to make bone scaffolds that can be implanted in the body. Its performance is tested by in vitro physical and biological methods, and its safety is evaluated by animal experiments. Methods: 3D printing technology was used to print the PLGA/HA composite three-dimensional stent biomaterial, and the tensile strength and bending strength of the stent material were tested with reference to GB/T1040 and GB/T9341 to verify its ability to support the proliferation and differentiation of hMSC. The biological evaluation standard (GB/T16886) evaluates the biocompatibility and biosafety of scaffoldmaterials in vitro and in vivo. Results: The porous 3D scaffold made of PLGA/HA composite material was successfully fabricated; the mechanical tensile strength and flexuralstrength of the composite material were 38 MPa and 42 MPa respectively, which were5.35 times and 5.25 times that of normal human cartilage; in vitro cell test It is proved that the 3D scaffold can support the proliferation and differentiation of hMSC into chondrocytes. The results of the biosafety test show that the scaffold meets the national medical device biological evaluation standards.
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Neumann, Laurie. « Synthesis of 5,15-A2BC-Type Porphyrins to Modify a Field-Effect Transistor for Detection of Gram-Negative Bacteria ». Dans SurfCoat Korea and Graphene Korea 2021 International Joint Virtual Conferences. Setcor Conferences and Events, 2021. http://dx.doi.org/10.26799/cp-surfcoat-graphene-korea-2021/2.

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Current biological sensing technologies of bacteria are time consuming, labor intensive and thus expensive. Furthermore, their accuracy and reproducibility could be improved. Conventional electrical measurement methods might combine high sensitive sensing systems with biological requirements. A promising approach is the trapping of bacteria on the surface of the gate-electrode of a modified field-effect transistor (FET) using porphyin based self-assembled monolayers (SAMs). 5,15-A2BC-type porphyrins were synthesized originating from a 5,15-diphenylporphyrin with the functionality to connect to a gold surface. The SAM formation on the surface of the gold electrode was proven by well-established analytical methods. In this work a synthesis route is presented for a linker which is attached to a peptide or cysteine group for trapping of Gram-negative bacteria. Fluorescence lifetime imaging microscopy (FLIM) measurements of porphyrin-stained bacteria were performed to verify the linkage ability.
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Luppi, Michael, Hao Gao, Ahsan Choudhury, Warren Hopkins, Saroj Das, Michele Pinelli et Quan Long. « Assessment of Structure Distortion of Paraffin Wax Histology Section of Human Carotid Atherosclerotic Plaque Specimen ». Dans ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206691.

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Paraffin wax histology analysis is treated as a golden standard to verify biological tissue microstructure. To generate a histology section, the tissue is subject to a sequence of dehydration processes to remove water from the tissue and replace it by wax to maintain the internal tissue structure. This process normally generates significant shrinkage in the specimen [1], adding uncertainties on quantifying region sizes based on histology sections, such as the area of lipid region, fibrous cap thickness (FCT) in human arterial plaque specimens.
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Zhou, Jack G., Alan Ostrow et Parkson Lee-Gau Chong. « Concurrent Design, Analysis and Prototype of a High Pressure Optical Cell for Physico-Chemical Studies of Biological Systems ». Dans ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0004.

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Abstract The commercially available high pressure optical cells, used in biological research, can only satisfy a limited range of experimental requirements. Current high pressure cell designs only allow for the measurement of single samples, thus limiting the data which researchers can obtain. We present a new design which enables users to introduce a second component to the original sample, while both components are under high pressure. This allows researchers to observe initial molecular interactions at high pressure via fiber optics and record data which was previously unobtainable. The design innovation which distinguishes the high pressure optical cell from existing models is the introduction of a laser-activated stopper system, which separates the two biological samples until the experimenter is ready to mix them. Concurrent Engineering methodologies and tools were used in conjunction with theoretical analysis to develop this innovative system. A high pressure cell prototype was built to further verify the new design and explore new challenges.
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Moreno, Andre, Kimberly Masiero Cola, Larissa Heberle et Marcelo Moreno. « RELATIONSHIP BETWEEN IMMUNOHISTOCHEMICAL CHARACTERIZATION AND FORM OF DIAGNOSIS OF BREAST CANCER ». Dans Scientifc papers of XXIII Brazilian Breast Congress - 2021. Mastology, 2021. http://dx.doi.org/10.29289/259453942021v31s1008.

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Introduction: Breast cancer is the most incident neoplasia among Brazilian women. According to immunogenetic characteristics, it is possible to verify that malignant breast neoplasms with greater biological activity would be those classified as luminary B, HER2+ and triple-negative, and that the one with the lowest biological activity would be the luminal subtype A. Thus, a mammography would be more likely to detect cancers with a low degree of biological characteristics such as “luminal A”. On the other hand, mammary carcinomas with greater potential for systemic dissemination show faster growth in the breast parenchyma and are detected predominantly by self-examination. Knowledge of this difference in the clinical behavior of mammary malignant neoplasms is important for the diagnosis of “interval” breast cancers, that is, breast cancer that appears in the period between the performance of annual screening mammograms. Objectives: Verify the relationship between immunohistochemical characterization of malignant breast neoplasms and the finding that motivated the medical consultation, in women with breast cancer and residents of Western Santa Catarina, Brazil. Methods: Observational, cross-sectional study, which included women diagnosed with breast cancer and treated at an oncology referral center in the city of Chapecó, state of Santa Catarina, Brazil, from January 2000 to December 2016. Patients that presented medical records whose main complaint was towards the diagnosis of breast cancer were included (example: nodule diagnosed by imaging exams, self-examination, clinical examination). Besides this, the breast injury related to this complaint should have been breast cancer diagnosed by an anatomopathological examination and an immunohistochemistry study. The project was developed in accordance to CEP/UNOCHAPECO no. 1819869. Results: Data from 209 patients were analyzed, from which 83 (39.7%) cases of breast cancer were detected by a mammography examination; 115 (55%) cases by breast self-examination and 11 (5.2%) cases by other forms of examination, which included clinical breast examination done by a doctor, magnetic resonance imaging and ultrasound. The luminal A immunohistochemical profile was more prevalent among patients who underwent breast cancer detection through mammography (62.6%). There was a correlation between lymph node invasion and the screening method, in which 78.6% of cancers detected by self-examination showed expansion to lymph nodes, while those detected by mammography presented an invasion rate of 45.7% (p=0.002). Conclusions: Breast cancer with immunohistochemical characterization, related to greater biological activity, were most often detected by self-examination, while neoplasms with indolent development were diagnosed predominantly by mammography.
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Honarmandi, Peyman. « Fabrication of Single-Crystal Nanospherical Hydroxyapatite Powder for Biomedical Applications ». Dans ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13326.

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The competence and compatibility of biomaterials is always challenging and demanding in biotech industries. Hydroxyapatite (HAp) is a useful biomaterial for biological applications due to its especial properties. In this paper, a dry mechanochemical process is introduced to produce hydroxyapatite nanoparticles. Structural and morphological properties of HAp powder are studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the single-crystal HAp nanospherical particles are successfully produced during milling process. Two different metallic and polymeric vials are applied and the results are compared for both vials. The results verify that the HAp nanoparticles are single crystal and their sizes are in the ranges of 12–24 nm.
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Miles, Robin, Phil Belgrader, Kerry Bettencourt, Julie Hamilton et Shanavaz Nasarabadi. « Dielectrophoretic Manipulation of Particles for Use in Microfluidic Devices ». Dans ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-0311.

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Abstract Amplification and hybridization of DNA are commonly used techniques to verify the presence of a specific DNA sequence in a test sample. Automatic sample handling to concentrate and purify a sample prior to amplification is desirable to increase the sensitivity of the test, to reduce the possibility of sample contamination such as inhibitors and to reduce reagent use. This paper explores the use of the dielectrophoretic force to manipulate DNA, Bacillus globigii spores and Erwinia herbicola bacteria to provide both concentration and purification as part of the sample handling functions in biological assay equipment. It was found that typical microfabricated structures with electrode gaps of 30μm operating at 5V could achieve very effective concentration of these particles.
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Fang, Yang, et Xiaobo Tan. « Design and Modeling of a Petal-Shape, Conjugated Polymer-Actuated Micropump ». Dans ASME 2008 Dynamic Systems and Control Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/dscc2008-2278.

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Conjugated polymers are emerging actuation materials for biomimetic robots and biomedical devices. Most previous research has been focused on the configurations of cantilever beams and linear extenders. However, the diaphragm configuration is needed in many potential applications, such as micro pumps for drug delivery and chemical/ biological analysis. In this paper the design of a conjugated polymer pumping diaphragm is investigated theoretically and experimentally. A petal-shape design is proposed to alleviate the edge constrains. Transfer function models from the actuation voltage to the diaphragm curvature and to the flow rate are obtained. Experiments are conducted to verify the effectiveness of the models. The transfer function models facilitate design optimization and the use of feedback control tools in dealing with the complicated behavior of conjugated polymer actuators.
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Rapports d'organisations sur le sujet "Verità biologica"

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Kularatne, Dhanushka N., Subhrajit Bhattacharya et M. Ani Hsieh. Computing Energy Optimal Paths in Time-Varying Flows. Drexel University, 2016. http://dx.doi.org/10.17918/d8b66v.

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Autonomous marine vehicles (AMVs) are typically deployed for long periods of time in the ocean to monitor different physical, chemical, and biological processes. Given their limited energy budgets, it makes sense to consider motion plans that leverage the dynamics of the surrounding flow field so as to minimize energy usage for these vehicles. In this paper, we present two graph search based methods to compute energy optimal paths for AMVs in two-dimensional (2-D) time-varying flows. The novelty of the proposed algorithms lies in a unique discrete graph representation of the 3-D configuration space spanned by the spatio-temporal coordinates. This enables a more efficient traversal through the search space, as opposed to a full search of the spatio-temporal configuration space. Furthermore, the proposed strategy results in solutions that are closer to the global optimal when compared to greedy searches through the spatial coordinates alone. We demonstrate the proposed algorithms by computing optimal energy paths around the Channel Islands in the Santa Barbara bay using time-varying flow field forecasts generated by the Regional Ocean Model System. We verify the accuracy of the computed paths by comparing them with paths computed via an optimal control formulation.
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Ghanim, Murad, Joe Cicero, Judith K. Brown et Henryk Czosnek. Dissection of Whitefly-geminivirus Interactions at the Transcriptomic, Proteomic and Cellular Levels. United States Department of Agriculture, février 2010. http://dx.doi.org/10.32747/2010.7592654.bard.

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Our project focuses on gene expression and proteomics of the whitefly Bemisia tabaci (Gennadius) species complex in relation to the internal anatomy and localization of expressed genes and virions in the whitefly vector, which poses a major constraint to vegetable and fiber production in Israel and the USA. While many biological parameters are known for begomovirus transmission, nothing is known about vector proteins involved in the specific interactions between begomoviruses and their whitefly vectors. Identifying such proteins is expected to lead to the design of novel control methods that interfere with whitefly-mediated begomovirus transmission. The project objectives were to: 1) Perform gene expression analyses using microarrays to study the response of whiteflies (B, Q and A biotypes) to the acquisition of begomoviruses (Tomato yellow leaf curl (TYLCV) and Squash leaf curl (SLCV). 2) Construct a whitefly proteome from whole whiteflies and dissected organs after begomovirus acquisition. 3) Validate gene expression by q-RTPCR and sub-cellular localization of candidate ESTs identified in microarray and proteomic analyses. 4) Verify functionality of candidate ESTs using an RNAi approach, and to link these datasets to overall functional whitefly anatomical studies. During the first and second years biological experiments with TYLCV and SLCV acquisition and transmission were completed to verify the suitable parameters for sample collection for microarray experiments. The parameters were generally found to be similar to previously published results by our groups and others. Samples from whole whiteflies and midguts of the B, A and Q biotypes that acquired TYLCV and SLCV were collected in both the US and Israel and hybridized to B. tabaci microarray. The data we analyzed, candidate genes that respond to both viruses in the three tested biotypes were identified and their expression that included quantitative real-time PCR and co-localization was verified for HSP70 by the Israeli group. In addition, experiments were undertaken to employ in situ hybridization to localize several candidate genes (in progress) using an oligonucleotide probe to the primary endosymbiont as a positive control. A proteome and corresponding transcriptome to enable more effective protein identification of adult whiteflies was constructed by the US group. Further validation of the transmission route of begomoviruses, mainly SLCV and the involvement of the digestive and salivary systems was investigated (Cicero and Brown). Due to time and budget constraints the RNAi-mediated silencing objective to verify gene function was not accomplished as anticipated. HSP70, a strong candidate protein that showed over-expression after TYLCV and SLCV acquisition and retention by B. tabaci, and co-localization with TYLCV in the midgut, was further studies. Besides this protein, our joint research resulted in the identification of many intriguing candidate genes and proteins that will be followed up by additional experiments during our future research. To identify these proteins it was necessary to increase the number and breadth of whitefly ESTs substantially and so whitefly cDNAs from various libraries made during the project were sequenced (Sanger, 454). As a result, the proteome annotation (ID) was far more successful than in the initial attempt to identify proteins using Uniprot or translated insect ESTs from public databases. The extent of homology shared by insects in different orders was surprisingly low, underscoring the imperative need for genome and transcriptome sequencing of homopteran insects. Having increased the number of EST from the original usable 5500 generated several years ago to >600,000 (this project+NCBI data mining), we have identified about one fifth of the whitefly proteome using these new resources. Also we have created a database that links all identified whitefly proteins to the PAVEdb-ESTs in the database, resulting in a useful dataset to which additional ESTS will be added. We are optimistic about the prospect of linking the proteome ID results to the transcriptome database to enable our own and other labs the opportunity to functionally annotate not only genes and proteins involved in our area of interest (whitefly mediated transmission) but for the plethora of other functionalities that will emerge from mining and functionally annotating other key genes and gene families in whitefly metabolism, development, among others. This joint grant has resulted in the identification of numerous candidate proteins involved in begomovirus transmission by B. tabaci. A next major step will be to capitalize on validated genes/proteins to develop approaches to interfere with the virus transmission.
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Shmulevich, Itzhak, Shrini Upadhyaya, Dror Rubinstein, Zvika Asaf et Jeffrey P. Mitchell. Developing Simulation Tool for the Prediction of Cohesive Behavior Agricultural Materials Using Discrete Element Modeling. United States Department of Agriculture, octobre 2011. http://dx.doi.org/10.32747/2011.7697108.bard.

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The underlying similarity between soils, grains, fertilizers, concentrated animal feed, pellets, and mixtures is that they are all granular materials used in agriculture. Modeling such materials is a complex process due to the spatial variability of such media, the origin of the material (natural or biological), the nonlinearity of these materials, the contact phenomenon and flow that occur at the interface zone and between these granular materials, as well as the dynamic effect of the interaction process. The lack of a tool for studying such materials has limited the understanding of the phenomena relevant to them, which in turn has led to energy loss and poor quality products. The objective of this study was to develop a reliable prediction simulation tool for cohesive agricultural particle materials using Discrete Element Modeling (DEM). The specific objectives of this study were (1) to develop and verify a 3D cohesionless agricultural soil-tillage tool interaction model that enables the prediction of displacement and flow in the soil media, as well as forces acting on various tillage tools, using the discrete element method; (2) to develop a micro model for the DEM formulation by creating a cohesive contact model based on liquid bridge forces for various agriculture materials; (3) to extend the model to include both plastic and cohesive behavior of various materials, such as grain and soil structures (e.g., compaction level), textures (e.g., clay, loam, several grains), and moisture contents; (4) to develop a method to obtain the parameters for the cohesion contact model to represent specific materials. A DEM model was developed that can represent both plastic and cohesive behavior of soil. Soil cohesive behavior was achieved by considering tensile force between elements. The developed DEM model well represented the effect of wedge shape on soil behavior and reaction force. Laboratory test results showed that wedge penetration resistance in highly compacted soil was two times greater than that in low compacted soil, whereas DEM simulation with parameters obtained from the test of low compacted soil could not simply be extended to that of high compacted soil. The modified model took into account soil failure strength that could be changed with soil compaction. A three dimensional representation composed of normal displacement, shear failure strength and tensile failure strength was proposed to design mechanical properties between elements. The model based on the liquid bridge theory. An inter particle tension force measurement tool was developed and calibrated A comprehensive study of the parameters of the contact model for the DEM taking into account the cohesive/water-bridge was performed on various agricultural grains using this measurement tool. The modified DEM model was compared and validated against the test results. With the newly developed model and procedure for determination of DEM parameters, we could reproduce the high compacted soil behavior and reaction forces both qualitatively and quantitatively for the soil conditions and wedge shapes used in this study. Moreover, the effect of wedge shape on soil behavior and reaction force was well represented with the same parameters. During the research we made use of the commercial PFC3D to analyze soil tillage implements. An investigation was made of three different head drillers. A comparison of three commonly used soil tillage systems was completed, such as moldboard plow, disc plow and chisel plow. It can be concluded that the soil condition after plowing by the specific implement can be predicted by the DEM model. The chisel plow is the most economic tool for increasing soil porosity. The moldboard is the best tool for soil manipulation. It can be concluded that the discrete element simulation can be used as a reliable engineering tool for soil-implement interaction quantitatively and qualitatively.
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