494 resultados para Sputter cones


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Purpose:We previously observed that anti- and pro-apoptotic genes of the Bcl-2 family were differentially expressed during the development of LCA in the Rpe65-/- mouse model (Cottet et al. 2006). Moreover, we reported that activation and translocation of pro-apoptotic Bax to the mitochondria was associated with apoptosis of rod photoreceptors as the disease progressed (Cottet et al. 2008). In this study we challenged whether disruption of the pro-apoptotic pro-apoptotic Bax protein is sufficient to protect photoreceptor cells against apoptosis. Methods:Apoptosis of photoreceptor cells was addressed by TUNEL assay on flatmounted retinas. Counting of the rod nuclei within the ONL was performed following hematoxylin/eosin histological staining of retina sections. Expression level and localization of photoreceptor gene markers were assessed by quantitative PCR and immunohistological analyses. Results:While expression of rod photoreceptor genes was decreased in Rpe65-deficient retina, expression level remained unchanged in Rpe65-/- / Bax-/- mice. Moreover, OS dysorganization and shortening as well as decrease in ONL thickness observed in diseased retina were prevented in mice lacking functional Bax protein. TUNEL assay confirmed that Bax-dependent rod photoreceptor apoptosis was abolished in Rpe65-/- / Bax-/- mice. However, early and fast degeneration of cone cells was not prevented in Rpe65-/- / Bax-/- mice, indicating that Bax-induced apoptotic pathway was not involved in the degenerating process of cones in Rpe65-deficient retina. Conclusions:Altogether, these data show for the first time that a single genetic mutation can trigger two independent apoptotic pathways in rod and cone photoreceptors in LCA disease. While pro-apoptotic Bax is essential to trigger rod photoreceptor apoptosis, early degeneration of cones is not dependent on Bax-mediated apoptotic pathway in Rpe65-deficientmice.

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The eye is a complex organ, which provides one of our most important senses, sight. The retina is the neuronal component of the eye and represents the connection with the central nervous system for the transmission of the information that leads to image processing. Retinitis pigmentosa (RP) is one of the most common forms of inherited retinal degeneration, in which the primary death of rods, resulting in night blindness, is always followed by the loss of cones, which leads to legal blindness. Clinical and genetic heterogeneity in retinitis pigmentosa is not only due to different mutations in different genes, but also to different effects of the same mutation in different individuals, sometimes even within the same family. My thesis work has been mainly focused on an autosomal dominant form of RP linked to mutations in the PRPF31 gene, which often shows reduced penetrance. Our study has led to the identification of the major regulator of the penetrance of PRPF31 mutations, the CNOT3 protein, and to the characterization of its mechanism of action. Following the same rationale of investigating molecular mechanisms that are responsible for clinical and genetic heterogeneity of retinitis pigmentosa, we studied a recessive form of the disease associated with mutations in the recently-identified gene FAMI61 A, where mutations in the same gene give rise to variable clinical manifestations. Our data have increased the knowledge of the relationship between genotype and phenotype in this form of the disease. Whole genome sequencing technique was also tested as a strategy for disease gene identification in unrelated patients with recessive retinitis pigmentosa and proved to be effective in identifying disease-causing variants that might have otherwise failed to be detected with other screening methods. Finally, for the first time we reported a choroidal tumor among the clinical manifestations of PTEN hamartoma tumor syndrome, a genetic disorder caused by germline mutations of the tumor suppressor gene PTEN. Our study has highlighted the heterogeneity of this choroidal tumor, showing that genetic and/or epigenetic alterations in different genes may contribute to the tumor development and growth. - L'oeil est un organe complexe, à l'origine d'un de nos sens les plus importants, la vue. La rétine est la composante neuronale de l'oeil qui constitue la connexion avec le système nerveux central pour la transmission de l'information et qui conduit à la formation des images. La rétinite pigmentaire (RP) est une des formes les plus courantes de dégénérescence rétinienne héréditaire, dans laquelle la mort primaire de bâtonnets, entraînant la cécité nocturne, est toujours suivie par la perte de cônes qui conduit à la cécité complète. L'hétérogénéité clinique et génétique dans la rétinite pigmentaire n'est pas seulement due aux différentes mutations dans des gènes différents, mais aussi à des effets différents de la même mutation chez des individus différents, parfois même dans la même famille. Mon travail de thèse s'est principalement axé sur une forme autosomique dominante de RP liée à des mutations dans le gène PRPF31, associées souvent à une pénétrance réduite, me conduisant à l'identification et à la caractérisation du mécanisme d'action du régulateur principal de la pénétrance des mutations: la protéine CNOT3. Dans la même logique d'étude des mécanismes moléculaires responsables de l'hétérogénéité clinique et génétique de la RP, nous avons étudié une forme récessive de la maladie associée à des mutations dans le gène récemment identifié FAMI61 A, dont les mutations dans le même gène donnent lieu à des manifestations cliniques différentes. Nos données ont ainsi accru la connaissance de la relation entre le génotype et le phénotype dans cette forme de maladie. La technique de séquençage du génome entier a été ensuite testée en tant que stratégie pour l'identification du gène de la maladie chez les patients atteints de RP récessive. Cette approche a montré son efficacité dans l'identification de variantes pathologiques qui n'auraient pu être détectées avec d'autres méthodes de dépistage. Enfin, pour la première fois, nous avons identifié une tumeur choroïdienne parmi les manifestations cliniques du PTEN hamartoma tumor syndrome, une maladie génétique causée par des mutations germinales du gène suppresseur de tumeur PTEN. Notre étude a mis en évidence l'hétérogénéité de cette tumeur choroïdienne, montrant que les altérations génétiques et/ou épigénétiques dans les différents gènes peuvent contribuer au développement et à la croissance tumorale.

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O artigo explora bases de sustentabilidade do valor patrimonial das chamadas culturas marginais, tomando como referente empírico as artes de musicar e de improvisar. aos preconceitos que associam a cultura popular à frivolidade se contrapõem evidências da sua criatividade. para isso, comparam-se tendências e influências musicais de um e outro lado do atlântico (portugal e brasil), na base de uma matriz partilhada de repentes e improvisações. os exemplos do fado e do samba são usados para ilustrar as variações simbólicas, no decurso do tempo, das produções culturais: dos antros de marginalidade podem emergir ícones de nacionalidade. em seguida, em um estudo de caso envolvendo jovens portugueses afrodescendentes, sem motivação extrínseca ou intrínseca para as aprendizagens do ensino formal, mostram-se reais possibilidades de emancipação através da música e da dança. finalmente, equaciona-se a possibilidade de a educação, dada a sua aposta no conhecimento, poder constituir uma importante plataforma de reconhecimento do valor patrimonial das culturas populares.

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Cone photoreceptors mediate visual acuity under daylight conditions, so loss of cone-mediated central vision of course dramatically affects the quality of life of patients suffering from retinal degeneration. Therefore, promoting cone survival has become the goal of many ocular therapies and defining the stage of degeneration that still allows cell rescue is of prime importance. Using the Rpe65(R91W/R91W) mouse, which carries a mutation in the Rpe65 gene leading to progressive photoreceptor degeneration in both patients and mice, we defined stages of retinal degeneration that still allow cone rescue. We evaluated the therapeutic window within which cones can be rescued, using a subretinal injection of a lentiviral vector driving expression of RPE65 in the Rpe65(R91W/R91W) mice. Surprisingly, when applied to adult mice (1 month) this treatment not only stalls or slows cone degeneration but, actually, induces cone-specific protein expression that was previously absent. Before the intervention only part of the cones (40% of the number found in wild-type animals) in the Rpe65(R91W/R91W) mice expressed cone transducin (GNAT2); this fraction increased to 64% after treatment. Correct S-opsin localization is also recovered in the transduced region. In consequence these results represent an extended therapeutic window compared to the Rpe65(-/-) mice, implying that patients suffering from missense mutations might also benefit from a prolonged therapeutic window. Moreover, cones are not only rescued during the course of the degeneration, but can actually recover their initial status, meaning that a proportion of altered cones in chromophore deficiency-related disease can be rehabilitated even though they are severely affected.

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Purpose: To describe the genotype/phenotype correlation associated with homozygous p.R108X mutation in the SPATA7 gene. Methods: A consanguineous nuclear family of Ethiopian origin was ascertained for genotypic and phenotypic characterization, including fundus photography, fundus autofluorescence (FAF), and full-field ERG. Molecular diagnosis was performed using a microarray. Results: Two of the 5 family members were affected with LCA. A homozygous c.322C>T (p.R108X) mutation in exon 5 of SPATA-7 was identified in both of them. The patients were 4 and 11 years old, respectively. Fundus examination revealed an unremarkable macular area, but optic nerve pallor, attenuated vascular calibre and deep retinal nummular deposits with para-arterial sparing predominant in the midperiphery. FAF showed multiples areas of hyperautofluorescence, corresponding to the deep retinal deposits. ERG was not recordable in the young patient, and showed severe rods/cones dysfunction in the older one. Conclusions: The literature describing genotype/phenotype correlation of SPATA-7 mutations in Leber congenital amaurosis (LCA) is still limited. We report the occurrence of para-arterial sparing in two sibs with SPATA7-linked LCA which may represent a clinical marker of this condition.

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O objetivo deste trabalho foi avaliar a distribuição da deposição de agrotóxicos pulverizados em duas cultivares de maçã (Malus domestica Borkh). Uma calda com traçador Rodamina B foi pulverizada, com equipamento do tipo carreta com cortina de ar, com dois tipos de calibrações. Em uma calibração foram utilizados bicos cones JA-1, JA-2 e JA-3 e na outra, bicos leque AVI 110 ISO-04 e bicos JA-1. Não houve diferenças entre as calibrações, mas a deposição nas plantas foi decrescente da região apical para a basal. Nas calibrações testadas, 25% do traçador aplicado perdeu-se no solo.

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The retinae of insectivores have been rarely studied, and their photoreceptor arrangements and expression patterns of visual pigments are largely unknown. We have determined the presence and distribution of cones in three species of shrews (common shrew Sorex araneus, greater white-toothed shrew Crocidura russula, dark forest shrew Crocidura poensis; Soricidae) and in the lesser hedgehog tenrec Echinops telfairi (Tenrecidae). Special cone types were identified and quantified in flattened whole retinae by antisera/antibodies recognizing the middle-to-long-wavelength-sensitive (M/L-)cone opsin and the short-wavelength-sensitive (S-)cone opsin, respectively. A combination of immunocytochemistry with conventional histology was used to assess rod densities and cone/rod ratios. In all four species the rods dominate at densities of about 230,000-260,000/mm2. M/L- and S-cones are present, comprising between 2% of the photoreceptors in the nocturnal Echinops telfairi and 13% in Sorex araneus that has equal diurnal and nocturnal activity phases. This suggests dichromatic color vision like in many other mammals. A striking feature in all four species are dramatically higher S-cone proportions in ventral than in dorsal retina (0.5% vs. 2.5-12% in Sorex, 5-15% vs. 30-45% in Crocidura poensis, 3-12% vs. 20-50% in Crocidura russula, 10-30% vs. 40-70% in Echinops). The functional and comparative aspects of these structural findings are discussed.

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Pathogenesis in the Rpe65(-/-) mouse model of Leber's congenital amaurosis (LCA) is characterized by a slow and progressive degeneration of the rod photoreceptors. On the opposite, cones degenerate rapidly at early ages. Retinal degeneration in Rpe65(-/-) mice, showing a null mutation in the gene encoding the retinal pigment epithelium 65-kDa protein (Rpe65), was previously reported to depend on continuous activation of a residual transduction cascade by unliganded opsin. However, the mechanisms of apoptotic signals triggered by abnormal phototransduction remain elusive. We previously reported that activation of a Bcl-2-dependent pathway was associated with apoptosis of rod photoreceptors in Rpe65(-/-) mice during the course of the disease. In this study we first assessed whether activation of Bcl-2-mediated apoptotic pathway was dependent on constitutive activation of the visual cascade through opsin apoprotein. We then challenged the direct role of pro-apoptotic Bax protein in triggering apoptosis of rod and cone photoreceptors.Quantitative PCR analysis showed that increased expression of pro-apoptotic Bax and decreased level of anti-apoptotic Bcl-2 were restored in Rpe65(-/-)/Gnat1(-/-) mice lacking the Gnat1 gene encoding rod transducin. Moreover, photoreceptor apoptosis was prevented as assessed by TUNEL assay. These data indicate that abnormal activity of opsin apoprotein induces retinal cell apoptosis through the Bcl-2-mediated pathway. Following immunohistological and real-time PCR analyses, we further observed that decreased expression of rod genes in Rpe65-deficient mice was rescued in Rpe65(-/-)/Bax(-/-) mice. Histological and TUNEL studies confirmed that rod cell demise and apoptosis in diseased Rpe65(-/-) mice were dependent on Bax-induced pathway. Surprisingly, early loss of cones was not prevented in Rpe65(-/-)/Bax(-/-) mice, indicating that pro-apoptotic Bax was not involved in the pathogenesis of cone cell death in Rpe65-deficient mice.This is the first report, to our knowledge, that a single genetic mutation can trigger two independent apoptotic pathways in rod and cone photoreceptors in Rpe65-dependent LCA disease. These results highlight the necessity to investigate and understand the specific death signaling pathways committed in rods and cones to develop effective therapeutic approaches to treat RP diseases.

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Purpose: C57/Bl6, Cpfl1-/- (Cone photoreceptors function loss 1; pure rod function), Gnat1alpha-/- (rod alpha-transducin; pure cone function) and Rpe65-/-;Rho-/- double knock-out mice were studied in order to distinguish the respective contributions of the different photoreceptor (PR) systems that enable light perception and mediate a visual reflex in adult Rpe65-/- mice using a simple behavioural procedure. Methods: Visual function was estimated using a rotating automatized optomotor drum covered with vertical black and white stripes at spatial frequencies of 0.025 to 0.5 cycles per degree (cpd) in both photopic and scotopic conditions. To evaluate the contribution as well as the light intensity threshold of each PR system, we tested the mouse strains with different luminances. Results: Stripe rotation elicits head movements in wild-type (WT) animals in photopic and scotopic conditions depending on the spatial frequency, whereas Cpfl1-/- mice show a reduced activity in the photopic condition and Gnat1alpha-/- mice an almost absent response in the scotopic condition. Interestingly, a robust visual response is obtained with Rpe65-/- knockout mice at 0.075 cpd and 0.1 cpd in the photopic condition. The residual rod function in the Rpe65-/- animals was demonstrated by testing Rpe65-/-;Rho-/- mice that present no response in photopic conditions. Conclusions: The optomotor test is a simple method to estimate the visual function, and to evaluate the respective contributions of rod and cone systems. Using this test, we demonstrate that in Rpe65-/- mice, devoid of functional cones and of detectable 11-cis-retinal protein, rods mimic in part the cone function by mediating vision in photopic conditions.

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SUMMARY The ability of neuronal processes to find their way along complex paths and to establish appropriate connections depends on continual rearrangements of the cytoskeletal components. The regulation of microtubules plays an important role for morphological changes underlying nevrite outgrowth, axonal elongation, and growth cone steering. SCG10 (superior cervical ganglion clone 10) is a neuronal growthassociated protein developmentally regulated and highly enriched in the neuronal growth cones. SCG10 presents a microtubule destabilizing activity that could participate to the regulation of microtubule dynamics and thus explain microtubule behaviors in the growth cone during axonal elongation and turning. It is here suggested that a tight control of the opposite effects on microtubules of SCG10 and the stabilizing microtubule-associated protein MAP1B allows a fine tuning of cytoskeletal rearrangement and may provide the required microtubule dynamic instability to promote axonal growth. Moreover, antibodyblockade of SCG10 function, that leads to growth cone pauses similar as those triggered by the guidance molecule EphB, and the modulation of SCG10 activity by the Rho GTPase Rnd1 suggest a potential role for SCG10 in the signal transduction pathways of extracellular guidance cues. The identification of the active zone protein Bassoon as a potential interaction partner for the SCG10-related protein NPC2, using atomic force microscopy as well as COS-7 and neuronal cell cultures, also gives new insights for a role of this protein family into the processes of synapse genesis or plasticity. Finally, SCG10 mutant mice generated by gene targeting and expressing a soluble form of the protein have been characterized during early postnatal development and in the adulthood. Due to the deletion of its membrane binding domain, SCG10 specific subcellular targeting to growth cones is compromised and results in impairments of motor and coordination development. Further histological analysis in the sciatic nerve reveal that these symptoms are associated with neurodegenerative signs. RESUME Une navigation correcte des prolongements cellulaires neuronaux leur permettant de former des connections appropriées repose sur de continuels réarrangements des constituants de leur cytosquelette. La régulation des microtubules joue notamment un rôle important dans les changements morphologiques qui accompagnent la croissance axonale et les réorientations du cône de croissance. SCG10 (superior cervical ganglion clone 10) est une protéine étroitement associée à la croissance neuronale, hautement régulée durant le développement et abondante au niveau du cône de croissance. SCG10 présente une activité déstabilisatrice sur les microtubules qui pourrait permettre une régulation des paramètres dynamiques propres aux microtubules et ainsi expliquer leur comportement durant la navigation du cône de croissance. Il est ici proposé qu'un contrôle précis des effets opposés de SCG10 et d'une autre protéine stabilisante associée aux microtubules (MAP1 B) permette un réglage fin des réarrangements du cytosquelette et puisse ainsi produire l'instabilité dynamique nécessaire à la croissance anale. Par ailleurs, le blocage de la fonction de SCG10 par un anticorps spécifique, conduisant à des pauses du cônes de croissance similaires à celles provoquées par la molécule de guidage EphB, ainsi que la modulation de l'activité de SCG10 par la Rho GTPase Rnd1 suggèrent une potentielle implication de SCG10 dans les voies de transduction des signaux provenant de molécules de guidage extracellulaires. L'identification d'une interaction de la protéine synaptique Bassoon avec la protéine NPC2 apparentée à SCG10, au moyen de la microscopie à force atomique et dans des cultures de cellules neuronales et COS-7, ouvre des perspectives concernant ces protéines dans la formation et la plasticité synaptiques. Finalement, des souris mutantes pour SCG10 produites par ciblage de gène et exprimant une forme soluble de la protéine ont été caractérisées durant la phase précoce du développement et à l'âge adulte. La délétion du domaine permettant l'ancrage de SCG10 aux membranes compromet sa sub-localisation au niveau du cône de croissance et résulte en l'apparition de troubles moteurs et de la coordination. Des analyses histologiques complémentaires au niveau du nerf sciatique montrent que ces symptômes sont associés avec des signes neurodégénératifs.

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Part 6 of the Manual on Uniform Traffic Control Devices (MUTCD) describes several types of channelizing devices that can be used to warn road users and guide them through work zones; these devices include cones, tubular markers, vertical panels, drums, barricades, and temporary raised islands. On higher speed/volume roadways, drums and/or vertical panels have been popular choices in many states, due to their formidable appearance and the enhanced visibility they provide when compared to standard cones. However, due to their larger size, drums also require more effort and storage space to transport, deploy and retrieve. Recent editions of the MUTCD have introduced new devices for channelizing; specifically of interest for this study is a taller (>36 inches) but thinner cone. While this new device does not offer a comparable target value to that of drums, the new devices are significantly larger than standard cones and they offer improved stability as well. In addition, these devices are more easily deployed and stored than drums and they cost less. Further, for applications previously using both drums and tall cones, the use of tall cones only provides the ability for delivery and setup by a single vehicle. An investigation of the effectiveness of the new channelizing devices provides a reference for states to use in selecting appropriate traffic control for high speed, high volume applications, especially for short term or limited duration exposures. This study includes a synthesis of common practices by state DOTs, as well as daytime and nighttime field observations of driver reactions using video detection equipment. The results of this study are promising for the day and night performance of the new tall cones, comparing favorably to the performance of drums when used for channelizing in tapers. The evaluation showed no statistical difference in merge distance and location, shy distance, or operating speed in either daytime or nighttime conditions. The study should provide a valuable resource for state DOTs to utilize in selecting the most effective channelizing device for use on high speed/high volume roadways where timely merging by drivers is critical to safety and mobility.

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Purpose: We previously demonstrated efficient retinal rescue of RPE65 mouse models (Rpe65-/- (Bemelmans et al, 2006) and Rpe65R91W/R91W mice) using a HIV1-derived lentiviral vector encoding for the mouse RPE65 cDNA. In order to optimize a lentiviral vector as an alternative tool for RPE65-derived Leber Congenital Amaurosis clinical trials, we evaluated the efficiency of an integration-deficient lentiviral vector (IDLV) encoding the human RPE65 cDNA to restore retinal function in the Rpe65R91W/R91W mice. Methods: An HIV-1-derived lentiviral vector expressing either the hrGFPII or the human Rpe65 cDNA under the control of a 0.8 kb fragment of the human Rpe65 promoter (R0.8) was produced by transient transfection of 293T cells. A LQ-integrase mutant was used to generate the IDLV vectors. IDLV-R0.8-hRPE65 or hrGFPII were injected subretinally into 1 month-old Rpe65R91W/R91W mice. Functional rescue was assessed by ERG (1 and 3 months post-injection) and cone survival by immunohistology. Results: An increased light sensitivity was detected by scotopic ERG in animals injected with IDLV-R0.8-hRPE65 compared to hrGFPII-treated animals or untreated mice. However the improvement was delayed compared to integration-proficient LV and observed at 3 months but not 1 month post-injection. Immunolabelling of cone markers showed an increased number of cones in the transduced area compared to control groups. Conclusions: The IDLV-R0.8-hRPE65 vectors allow retinal improvement in the Rpe65R91W/R91W mice. Both rod function and cone survival were demonstrated even if there is a delay in the rescue as assessed by scotopic ERG. Integration-deficient vectors minimize insertional mutagenesis and thus are safer candidates for human application. Further experiments using large animals are now needed to validate correct gene transfer and expression of the RPE65 gene as well as tolerance of the vector after subretinal injection before envisaging a clinical trial application.

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SCG10 is a neuron-specific, membrane-associated protein that is highly concentrated in growth cones of developing neurons. Previous studies have suggested that it is a regulator of microtubule dynamics and that it may influence microtubule polymerization in growth cones. Here, we demonstrate that in vivo, SCG10 exists in both phosphorylated and unphosphorylated forms. By two-dimensional gel electrophoresis, two phosphoisoforms were detected in neonatal rat brain. Using in vitro phosphorylated recombinant protein, four phosphorylation sites were identified in the SCG10 sequence. Ser-50 and Ser-97 were the target sites for protein kinase A, Ser-62 and Ser-73 for mitogen-activated protein kinase and Ser-73 for cyclin-dependent kinase. We also show that overexpression of SCG10 induces a disruption of the microtubule network in COS-7 cells. By expressing different phosphorylation site mutants, we have dissected the roles of the individual phosphorylation sites in regulating its microtubule-destabilizing activity. We show that nonphosphorylatable mutants have increased activity, whereas mutants in which phosphorylation is mimicked by serine-to-aspartate substitutions have decreased activity. These data suggest that the microtubule-destabilizing activity of SCG10 is regulated by phosphorylation, and that SCG10 may link signal transduction of growth or guidance cues involving serine/threonine protein kinases to alterations of microtubule dynamics in the growth cone.

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GENDER EMPOWERMENT: EFFECTS OF GODS, GEOGRAPHY, AND GDP¦Fenley, M., & Antonakis, J.¦ABSTRACT¦We examined the determinants of women's empowerment in the economy and political leadership in 178 countries. Given the androcentric nature of most religions, we hypothesized that high degrees of country-level theistic belief create social conditions that impede the progression of women to power. The dependent variable was the Gender Empowerment index of the United Nations Development Program, which captures the participation of women in political leadership, management, and their share of national income. Controlling for GDP per capita as well as the fixed-effects of the dominant type of religion and legal origin and instrumenting all endogenous variables with geographic or historical variables, our results show that atheism has a significant positive effect on gender empowerment. These results are driven by the rule of law, which in addition to being a catalyst for economic development, appears to crowd-out the informal regulation of behavior due to religious norms.¦DEVELOPING WOMEN LEADERS: COMPARING A TRANSFORMATIONAL AND A CHARISMATIC LEADERSHIP INTERVENTION¦Fenley, M., Jacquart, P., & Antonakis, J.¦ABSTRACT¦Along with a gender imbalance in leadership role occupancy, most leadership interventions have been conducted with samples of men. We conducted an experiment wherein we assigned female participants (n = 38, mean age = 35 years) to one of two conditions: Transformational (i.e., "standard") leadership training or charismatic leadership training. The two interventions were essentially equivalent, except that we also focused on developing the "charismatic leadership tactics" (e.g., rhetorical skills) of participants in the charismatic condition. After the interventions, we randomly assigned participants into problem-solving teams that required extensive interaction. Each team had an equal number of participants having received transformational training or charismatic training. At the end of the team exercises, participants rated each of their team members on a leadership prototypicality measure. Results indicated that those who received charismatic training scored higher (a) on prototypicality (standardized  = .42) and (b) on a test of declarative knowledge of charismatic rhetorical strategies (i.e., a manipulation check, standardized  = .76). Furthermore, the score on the test fully mediated the effect of the treatment on prototypicality (standardized indirect  = .32). We discuss the importance and practical implications of these results.¦CHANGING ATTITUDES TOWARDS WOMEN IN A MALE SEX-TYPE WORK ENVIRONMENT: EVIDENCE FROM A FIELD EXPERIMENT IN EUROPEAN ATHLETICS¦Fenley, M.¦ABSTRACT¦Most sports organizations have a similar gender gap in leadership as do the majority of non-sport organizations. Women's careers sputter somewhere at coaching level positions and few women obtain top leadership positions. Greater awareness of gender inequalities in general, and in leadership in particular, could decrease gender discrimination and increase women's presence at upper levels. The goal of this study was to evaluate the impact of an intervention using an online gender awareness exercise. Participants (n = 1,001 participants, n = 32 countries) were randomly assigned to one of eight conditions in a 2 (a discriminating perspective-taking story or a non-discriminating perspective-taking story) by 2 (gender quiz or no gender quiz) by 2 (diversity quiz or no diversity quiz) factorial design. The results show that the online perspective taking exercise changed initial sexist attitudes. Participants having taken a diversity quiz had less sexist attitudes (as measured by the Modern- and Old-fashioned sexism scale) than did participants who did not take the diversity quiz (irrespective of perspective-taking story). The combination of having taken a diversity quiz with a gender quiz had the biggest impact on attitudes for the non-discriminating story.

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1. Costs of reproduction lie at the core of basic ecological and evolutionary theories, and their existence is commonly invoked to explain adaptive processes. Despite their sheer importance, empirical evidence for the existence and quantification of costs of reproduction in tree species comes mostly from correlational studies, while more comprehensive approaches remain missing. Manipulative experiments are a preferred approach to study cost of reproduction, as they allow controlling for otherwise inherent confounding factors like size or genetic background. 2. Here, we conducted a manipulative experiment in a Pinus halepensis common garden, removing developing cones from a group of trees and comparing growth and reproduction after treatment with a control group. We also estimated phenotypic and genetic correlations between reproductive and vegetative traits. 3. Manipulated trees grew slightly more than control trees just after treatment, with just a transient, marginally non-significant difference. By contrast, larger differences were observed for the number of female cones initiated 1 year after treatment, with an increase of 70% more cones in the manipulated group. Phenotypic and genetic correlations showed that smaller trees invested a higher proportion of their resources in reproduction, compared with larger trees, which could be interpreted as an indirect evidence for costs of reproduction. 4. Synthesis. This research showed a high impact of current reproduction on reproductive potential, even when not significant on vegetative growth. This has strong implications for how we understand adaptive strategies in forest trees and should encourage further interest on their still poorly known reproductive life-history traits.