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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

How Mobile Phones Can Spark an Entrepreneurial Revolution

Choe, Alison 01 January 2017 (has links)
In the last decade, there has been an exponential rise in mobile phones in both developed and developed countries. In light of that, this paper investigates whether the expansion of such mobile networks leads to increased entrepreneurial activity. By conducting panel regressions, I find the degree to which various stages of entrepreneurial activity is affected by increased mobile phone subscription rates. I use data from 80 countries from 2007 to 2015 and parse out the different effects between developing and developed countries, and between males and females. I find that larger mobile networks encourage entrepreneurship, particularly in the early stages, with a larger benefit experienced by developed countries compared to developing countries. In addition, more females than males engage in early-stage entrepreneurship due to increased mobile phone subscription rates in developing countries. However, an opposite trend is observed in developed countries. Finally, I also consider potential implications on economic development as a result of such increased business formation.
132

Financial Crisis, Inclusion and Economic Development in the US and OIC Countries

Hossain, Shadiya T 16 December 2016 (has links)
The following dissertation contains two distinct empirical essays which contribute to the overall field of Financial Economics. Chapter 1, entitled “Financial Inclusion and Economic Development in OIC Member Countries,” examines whether the presence of Islamic finance promotes development and alleviates poverty. To do so, we estimate the influence of financial inclusion variables on development and poverty variables for OIC countries. Using data from the World Bank, we use dynamic panel analysis using methodology similar to Beck et al (2000) to study the effects of financial inclusion on economic development and use simple cross-sectional analysis similar to Beck et al (2004) to study the effects on poverty alleviation. We find that the countries with Islamic finance tend to outperform the rest of the world. We believe that the ability of financial institutions offering Shari’a compliant services to bring otherwise excluded people under the financial system plays a major role in increased development and reduced poverty in those countries. The results support our view that financial inclusion is causing development. Chapter 2 entitled, “Asymmetric Market Reactions to the 2007-08 Financial Crisis: From Wall Street to Main Street,” examines the impact of significant news events during the 2007 – 2008 financial crisis on the abnormal stock returns for portfolios of financial and real sector firms. We recognize 17 significant news events from 2007 and 2008 and create equity portfolios using daily CRSP data from January 1, 2006 to December 31, 2009. We estimate event announcement interval abnormal returns in the context of an asset pricing model similar to Fama and French (1993) and Carhart (1997). We document significant negative abnormal returns for the portfolio of non-financial firms, and the smallest firms exhibit the largest negative abnormal returns, an indication of a significant spillover of financial market news to real sector stock returns. Smaller financial firms also exhibit negative abnormal event returns, and these results are driven by broker-dealer, depository, holding-investment, and real estate firms. The results provide new evidence regarding the incorporation of news events into asset prices during financial crises.
133

Degree Matters: The Impact of a Leader’s Foreign Education on His Country’s Economic Development

Yu, Zhongyi 01 January 2017 (has links)
I analyze the correlation between a nation leader’s foreign education experience and their nation’s GDP growth and economic freedom in African, Asian, and South American countries. There is a statistically significant correlation between a leader’s foreign education and the country’s GDP growth rate, especially in Africa. Data also shows that a leader’s foreign education is positively correlated with his country’s economic freedom. Despite the fact that the regressions can only demonstrate correlation as opposed to causation relationships among variables, further analysis of the results concludes that a leader’s education and the country’s development are reciprocal. The findings of this paper shine light on future policy directions for developing countries.
134

Fetal skeletal imaging using 3D ultrasound and the impact of maternal vitamin D

Ioannou, Christos January 2012 (has links)
Background: Previous research suggests that vitamin D deficiency during pregnancy may be associated with suboptimal fetal growth, but direct evidence is lacking. Our objectives were 1) to develop a method for measurement of the fetal sphenoidal fontanelle area (FA) and femur volume (FV) using 3D ultrasound; 2) to create normal charts for FA and FV; and 3) to correlate FA and FV with maternal vitamin D concentration. Methods: FA measurement in 3D was evaluated in vitro and in vivo. Different segmentation methods for FV measurement were explored. A novel FV method was described which consists of three linear measurements and a volume equation; this was validated in vitro and also by comparing FV measured sonographically to the true volume assessed by computed tomography (CT), in 6 cases following pregnancy termination. A cohort of 868 uncomplicated pregnancies was selected on the basis of strict inclusion criteria; participants underwent serial ultrasound scans for FV and multilevel modeling was used for the creation of a “prescriptive” FV chart. Finally, a different cohort of 357 healthy pregnant women had serum vitamin D levels and FV ultrasound at 34 weeks gestation and dual emission x-ray absorptiometry (DEXA) of their neonates in order to investigate the prenatal determinants of fetal bone mass. Results: FA measurement was accurate in vitro, but unreliable in vivo and was therefore abandoned. A novel FV method had excellent agreement with CT and superior repeatability compared with segmentation-based methods. A normal FV chart was created and the regression equations for the median and percentile values were presented. Vitamin D demonstrated a significant correlation with FV. Conclusions: FV is a reliable sonographic marker of skeletal growth. Maternal vitamin D deficiency is associated with reduced FV. This finding has public health implications as reduced bone mass may increase the lifetime risk of osteoporosis, through fetal programming.
135

Efeitos do uso da Cannabis sativa durante a gestação sobre o desenvolvimento pulmonar: estudo experimental em camundongos / Effects of Cannabis sativa during gestation on lung development: an experimental study in mice

Belotti, Luciano 19 June 2019 (has links)
A Cannabis sativa é a droga ilícita usada com maior frequência por gestantes. O Delta9-tetrahidrocanabinol é o canabinóide principal responsável pelos efeitos psicoativos agindo principalmente nos receptores canabinóides 1 no cérebro. O consumo de Cannabis durante a gestação pode afetar o sistema endocanabinóide causando impactos na fase implantacional e no desenvolvimento fetal. Além disso, o Delta9- tetrahidrocanabinol é uma substância que pode atravessar a barreira feto-placentária e estar presente no leite materno. Sabe-se, no entanto, que qualquer estímulo ou insulto em um período crítico de desenvolvimento embrionário-fetal pode representar consequências mais tarde na vida. A fumaça de Cannabis contém elementos tóxicos prejudiciais semelhantes aos da fumaça de cigarro, logo o uso crônico de Cannabis tem sido associado a efeitos deletérios sobre o sistema respiratório. Embora vários estudos abordarem os efeitos da exposição à Cannabis sativa, escassos são aqueles que estudam a exposição gestacional e seus efeitos na prole. Além disso, os efeitos da Cannabis sativa sobre o desenvolvimento pulmonar são pouco conhecidos. O objetivo deste estudo é analisar os efeitos do uso da Cannabis sativa no desenvolvimento pulmonar da prole de camundongos, cujas mães foram expostas no período de gestação e analisar os efeitos no próprio tecido pulmonar dessas mães. Camundongos fêmeas grávidas (BALB/c) com aproximadamente 3 meses foram expostas à fumaça de Cannabis sativa ou ar filtrado por um período de 13 dias. Após as exposições os pulmões e os fetos das fêmeas grávidas foram coletados e o perfil inflamatório pulmonar avaliado no lavado broncoalveolar. As análises morfologia tecidual foram conduzidas e avaliadas utilizando os parâmetros estereológicos do volume pulmonar total, volume total e densidade de volume dos compartimentos pulmonares (parênquima pulmonar, vias aéreas, vasos sanguíneos, espaços aéreos alveolares, septos alveolares, áreas de superfície total e densidade de superfície dos alvéolos). Adicionalmente foram incluídas as análises de dissector físico para a estimativa de volume médio alveolar, densidade numérica e o número total de alvéolos para as proles com 20 e 60 dias de idade. As análises estereológicas das fêmeas grávidas mostraram um aumento significativo no volume total pulmonar, no volume total dos septos e no volume total dos espaços aéreos alveolares, quando comparados com as fêmeas grávidas expostas ao ar filtrado (grupo controle). Nos fetos com 18 dias de idade gestacional, houve uma diminuição significativa no volume total pulmonar, no volume total e na densidade de volume de sacos alveolares, no volume total e na densidade de volume de mesênquima, quando comparados com o grupo controle. Na prole com 20 dias de idade, houve um aumento no volume total, na densidade de volume e de superfície das vias aéreas, quando comparados com o grupo controle. Na prole com 60 dias de idade, houve um aumento no volume total do espaço aéreo alveolar, na densidade de volume do espaço aéreo alveolar, na densidade de superfície dos septos alveolares e na estimativa do número total de alvéolos, quando comparados com o grupo controle. Já os parâmetros de densidade de volume dos septos alveolares, área de superfície total dos septos alveolares e espessura dos septos alveolares, mostraram-se diminuídas quando comparados com o grupo controle. Os resultados mostraram que a exposição à fumaça de Cannabis é capaz de induzir alterações morfológicas no tecido pulmonar de camundongos (BALB/c) fêmeas grávidas e nas suas respectivas proles / Cannabis sativa is the illicit drug most frequently used by pregnant women. Delta9-tetrahydrocannabinol is the main cannabinoid responsible for psychoactive effects and acts mainly on the cannabinoid 1 receptors in the brain. Cannabis use during pregnancy can affect the endocannabinoid system causing impacts on the implantation phase and fetal development. In addition, Delta9-tetrahydrocannabinol is a substance that can cross the fetal-placental barrier and be present in breast milk. It is known, however, that any stimulus or insult in a critical period of embryonic-fetal development can have consequences later in life. Cannabis smoke contains harmful toxic elements similar to those of cigarette smoke, so chronic use of Cannabis has been associated with deleterious effects on the respiratory system. Although several studies address the effects of exposure to Cannabis sativa, few are those who study gestational exposure and its effects on offspring. In addition, the Cannabis sativa effects on lung development are poorly understood. The aim of this study is to analyze the effects of Cannabis sativa on the mice offspring lung development whose mothers were exposed during the gestation period and to analyze the effects on the lung tissue of these mothers. Pregnant female mice (BALB / c) with approximately 3 months were exposed to Cannabis sativa smoke or filtered air for 13 days. After the exposures the lungs and fetuses of the pregnant females were collected and the lung inflammatory profile evaluated in the bronchoalveolar lavage. The tissue morphology analyzes were conducted and evaluated using the stereological parameters of total lung volume, total volume and volume density of lung compartments (lung parenchyma, airways, blood vessels, alveolar air spaces, alveolar septa, total surface areas and alveoli surface density). In addition, physical dissector analyzes were used to estimate the mean alveolar volume, numerical density and the total number of alveoli for offspring at 20 and 60 days of age. Stereological analyzes of pregnant females showed a significant increase in total lung volume, total septal volume and alveolar air spaces total volume when compared to pregnant females exposed to filtered air (control group). In fetuses with 18 days gestational age, there was a significant decrease in total lung volume, total volume and volume density of saccules, total volume and volume density of mesenchymal stroma when compared to the control group. In the 20-day-old offspring, there was an increase in total volume, volume density and surface density of airway when compared to the control group. In the 60-day-old offspring, there was an increase in total alveolar airspace volume, alveolar airspace volume density, alveolar septal surface density, and total alveolar number estimation, as compared to the control group. The alveolar septa volume density, alveolar septa total surface area and alveolar septa thickness were decreased when compared to the control group. The results showed that exposure to Cannabis smoke is able to induce morphological changes in the lung tissue of pregnant (BALB / c) mice and their respective offspring
136

Neurodevelopmental delays in children with perinatally acquired human immunodeficiency virus infection, with respect to antiretroviral therapy initiation and virological suppression

Strehlau, Renate January 2013 (has links)
A research report submitted to the Faculty of Health Sciences, the University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Medicine in Child Health Neurodevelopment Johannesburg, 2013 / Human Immunodeficiency Virus (HIV) infection in infancy may influence the developing brain and lead to adverse neurodevelopmental consequences. We aim to describe the neurodevelopmental characteristics of a cohort of young children infected with HIV prior to antiretroviral therapy (ART) initiation and after achieving viral suppression. A retrospective analysis of data collected as part of a randomised equivalence trial between April 2005 and May 2009, at a hospital in Johannesburg, South Africa. 195 HIV-infected children under 2 years of age were assessed. A simple, inexpensive screening questionnaire (Ages and Stages Questionnaire - ASQ) was used to identify neurodevelopmental delays. The ASQ was administered prior to ART initiation, and again after viral suppression on a protease inhibitor-based regimen had been achieved. Median age pre-ART was 8.8 months (range 2.2 - 24.9), 53.9% were male. Mean time to viral suppression was 9.4 months (range 5.9 - 14.5) and the ASQ was administered to 108 caregivers at this time. Compared to pre-ART, at viral suppression, there was significant reduction in the proportion of children failing the gross motor (31.5% vs. 13%, p<0.01), fine motor (21.3% vs. 10.2%, p=0.02), problem solving (26.9% vs. 9.3%, p<0.001) and personal social (17.6% vs. 7.4%, p=0.02) domains. The proportion of children failing the communication domain was similar at each time point (14.8% vs. 12%, p=0.61). At time of viral suppression 10.2% failed at least one of the five domains. Achieving viral suppression on ART resulted in significant improvements in the neurodevelopmental function of young HIV-infected children, however, neurodevelopmental problems still persisted in a large proportion. Appropriate screening for neurodevelopmental delay and timely referral could help improve outcomes.
137

A influência da obstrução das vias aéreas superiores na determinação do tipo facial / The influence of the obstruction of the superior airway in the determination of the facial type

Freire-Maia, Belini Augusto Villalba 16 April 2010 (has links)
O objetivo neste trabalho foi de analisar a geometria nasal, a nasofaringe e a orofaringe, em crianças respiradoras orais com indicação de cirurgia desobstrutiva das vias aéreas superiores, e verificar a existência de uma possível influência direta da respiração na determinação do tipo facial. Foram avaliadas 657 crianças e, dentre elas, foram selecionadas 75, que se submeteram a avaliação otorrinolaringológica por meio de exames clínico, de radiografia cavum e/ou nasofibroscopia, e com as quais ficaram evidenciadas as obstruções das vias aéreas superiores com indicação cirúrgica. Ao final 41 crianças (21 do gênero masculino e 20 do feminino), entre 6,16 e 14,66 anos de idade, brasileiras, leucodermas, sem história de tratamento ortodôntico ou otorrinolaringológico cirúrgico (remoção de tonsilas faringeanas, palatinas, ou estruturas internas da cavidade nasal), aceitaram participar do estudo. Foram obtidas telerradiografias em norma lateral para a determinação do tipo facial e realizado o exame de rinometria acústica para a obtenção da área transversal mínima da cavidade nasal. A análise estatística dos dados (ANOVA, Razão de Verossimilhanças, análises de variâncias com medidas repetidas com dois fatores, comparações múltiplas de Bonferroni, teste Kruskal- Wallis; com nível de significância de 5%) e a interpretação dos resultados obtidos não mostraram diferença estatisticamente significativa na área total em MCA1 e MCA2 entre os tipos faciais (p > 0,05). Além disso, a obstrução das tonsilas faringeanas e palatinas avaliadas separadamente ou combinadas não variou estatisticamente segundo os tipos faciais (p = 0,582 para tonsila faringeana e p = 0,733 para tonsila palatina; e p = 0,925 quando combinadas). Conclui-se que, no presente estudo, não foi encontrada evidência de que a obstrução das vias aéreas superiores tenha influência determinante na definição do tipo facial. / The objective of this paper was to analyze the nasal geometry, the nasopharynx and the oropharynx in oral breathing children with indication for surgery clearence upper airway, in order to verify the existence of a possible direct influence of breathing in the determination of the facial type. A group of 657 children was evaluated and, among them, 75 were selected for otorhinolaryngologic evaluation through clinical exams, cavum radiography and/or nasal endoscopy , when the obstruction of the upper airway with surgical indication has been confirmed. From this subgroup, 41 children agreed to participate in the study (21 males: 20 females), with ages between 6,16 and 14,66 years, brazilians, whites, with no history of orthodontic treatment nor otorhinolaryngologic surgery (removal of the pharyngeal or palatine tonsils or internal structures of the nasal cavity). Radiographs were taken in lateral norm for the determination of the facial type and the acoustic rhinometry exam was performed for the determination of the nasal minimal transversal area. The statistical analyses of the data were made with the variance analysis (ANOVA), likelihood ratio test, analyses of variance with measures repeated with two factors, Bonferroni multiple comparisons, and Kruskal-Wallis test. The significance level was chosen as 0.05. No statistically significant difference was detected in the total area in MCA1 and MCA2 between the facial types. Besides that, the obstruction of the pharyngeal or palatine tonsils, taken separately or in combination, did not vary statistically according to the facial pattern (p = 0.582 for pharyngeal tonsil; p = 0.733 for palatine tonsil; and p = 0.925 when combined). Therefore, in the present study, no evidence has been found that the obstruction of the superior airway has determinant influence in the determination of the facial type.
138

O papel da dopplervelocimetria do ducto venoso de 11 a 13 6/7 semanas no rastreamento de anomalias cromossômicas, malformações estruturais e prognóstico fetal / The role of ductus venosus assessment in chromosomal abnormalities, structural defects and fetal prognosis at 11 to 13 6/7 weeks\' gestation

Toyama, Julio Mitsutomo 23 June 2004 (has links)
Objetivos: avaliar a contribuição do fluxo anormal no ducto venoso de 11 a 13 6/7 semanas no rastreamento de anomalias cromossômicas, defeitos estruturais e prognóstico gestacional. Método: 1221 gestações únicas foram submetidas a Dopplervelocimetria do ducto venoso após o rastreamento pela translucência nucal (TN). Resultados: os defeitos cromossômicos foram diagnosticados em 22 fetos. O fluxo no ducto venoso estava anormal em 84 fetos, a TN estava acima do 95o percentil em 160 casos e ambos marcadores estiveram anormais em 41 fetos. A sensibilidade, especificidade, valores preditivos positivo e negativo para defeitos cariotípicos corresponderam respectivamente a 86,4%, 86,9%, 11,9% e 99,7% considerando a TN aumentada, 68,2%, 96,9%, 31,3%, 99,3% para anomalias do fluxo do ducto venoso e 68,2%, 97,6%, 36,6%, 99,3% analisando ambos os marcadores. Investigando malformações estruturais, esses valores foram de 43,8%, 92,9%, 8,3%, 99,1% para uma TN aumentada, 25%, 92,6%, 4,8%, 98,8% para anomalias do fluxo do ducto venoso e 25%, 97,9%, 15,4%, 98,9% para ambos os marcadores. Nos casos com TN aumentada, a proporção de nascidos vivos morfológica e cariotipicamente normais diminui de 93,8% nos fetos com fluxo no ducto venoso normal para 77,3%, quando anormal. Conclusão: a avaliação do ducto venoso de 11 a 13 6/7 semanas de gestação pode ser utilizada no rastreamento de anomalias cromossômicas fetais e pode ajudar a reduzir a taxa de falso-positivo quando combinado com a medida da TN. Em fetos com TN aumentada o fluxo anormal no ducto venoso aumenta a probabilidade de resultados gestacionais adversos / Objective: To evaluate the association between abnormal ductus venosus at 11 - 13 6/7 weeks\' gestation and chromosomal abnormalities, structural defects and fetal outcome. Methods: Ductus venosus waveform (DVFVW) and nuchal translucency (NT) thickness were prospectively evaluated in 1221 singleton pregnancies. Results: The DVFVW was abnormal in 84 cases, NT was above the 95th centile in 160 cases and both markers were observed in 41 fetuses. Chromosomal defects were diagnosed in 22 fetuses. The sensitivity, specificity and positive predictive values for an abnormal karyotype were respectively 86.4%, 86.9%, 11.9% for an increased NT; 68.2%, 96.9%, 31.3% for DVFVW abnormalities and 68.2%, 97.6%, 36.6% for both markers. Regarding structural defects, this values were 43.8%, 92.9%, 8.3% for an abnormal NT, 25%, 92.6%, 4.8% for DVFVW abnormalities and 25%, 97.9%, 15.4% for both. Considering those cases of unexplained fetal demise, the percentages were 44.4%, 85.9%, 5% for NT abnormalities, 22.2%, 92.6%, 4.8% for an abnormal DVFVW and 22.2%, 98%, 15.4% for both. In cases with increased NT measurement, the percentage of livebirths with normal karyotype and no major fetal structural defects decreased from 93.8% in normal DVFVW fetuses to 77.3%, when abnormal. Conclusion: Ductus venosus assessment at 11 - 13 6/7 weeks\' gestation is useful in screening for fetal chromosomal abnormalities and may help to reduce the false-positive rate when combining with NT thickness measurement. Abnormal DVFVW is also associated with an increase of adverse perinatal outcome in fetuses with enlarged NT. However, the value of DVFVW assessment in cases with normal NT measurement is unclear
139

Desenvolvimento financeiro, crescimento e desigualdade nos estados brasileiros / Financial development, growth and unequality in the Brazilian states

Zara, Thaís Marzola 10 November 2006 (has links)
Este trabalho tem como objetivo investigar a relação entre desenvolvimento financeiro e crescimento, bem como desenvolvimento financeiro e desigualdade, numa análise regional, para estados brasileiros. Utilizando a metodologia empregada na literatura empírica internacional, as conclusões obtidas são de que: a) o acesso ao crédito é uma das variáveis importantes para a explicação do crescimento estadual e da desigualdade na distribuição de renda; b) o tamanho do crédito em si aparece como relevante para a explicação do crescimento, mas, quando controlados os efeitos das características próprias de cada estado, esta relação deixa de ser significante; e c) o tamanho do crédito está negativamente relacionado à desigualdade de renda, isto é, mais crédito corresponde a pior distribuição. Este último resultado é contra-intuitivo e são sugeridas duas explicações para isso. A primeira razão possível é de que o crédito possa estar sendo capturado pelas camadas de maior renda / empresas de maior porte, não chegando às classes de menor renda / micro e pequenas empresas, o que acentuaria o quadro de má distribuição de renda. O acesso ao crédito, ao contrário, melhora a distribuição de renda. Além disso, é possível que, como uma parte importante do crédito é direcionada pelo governo, este pode estar deliberadamente enviando mais recursos aos estados inicialmente mais desiguais, o que explicaria o resultado de que mais crédito está associado a mais desigualdade. / This paper?s goal is to investigate the relationship between financial development and growth and between financial development and wealth distribution, using a regional approach, through Brazilian states. Using the methodological approach common to the international empiric literature, the conclusions are: a) access to credit is one of the relevant variables when explaining the states growth and the uneven wealth distribution; b) size of credit itself appears to be relevant when explaining growth, however, when discounting the states fixed effects, the relationship ceases to be significant; and c) credit size is negatively related to the wealth distribution, meaning that more credit is linked to a more uneven wealth distribution. This last result is not expected and there are two suggested reasons for it. The first one is that the credit is being captured by the richer lays of population / bigger firms, and it is not being able to reach the poorest lays / smaller firms, thus enhancing the unequal distribution. Credit access, on the other hand, improves the wealth distribution. Besides, it is possible that since a great credit share is directed by the government, it could be intentionally sending more resources to the more uneven states, explaining how more credit could be associated with more inequality.
140

Evolution, variabilité et développement de la mandibule chez les hominidés : intérêt d'une approche structurale centrée sur le canal mandibulaire / Evolution, variability and development of the mandible in hominids : utility of an integrative method based on the mandibular canal

Curien, Rémi 29 October 2010 (has links)
La mandibule est constituée d'unités distinctes intégrées autour d'un tuteur, le nerf alvéolaire inférieur dont l'artefact osseux est le canal mandibulaire. Une étude de la variabilité, de l'évolution et du développement de la mandibule chez les hominidés est donc menée selon une méthodologie distinguant les unités mandibulaires tout en les articulant autour du canal mandibulaire.L'étude porte sur 453 mandibules, représentant les genres actuels Homo, Pan, et Gorilla ainsi que certaines espèces fossiles de la lignée humaine. Les mesures sont effectuées numériquement sur des photographies sagittales standardisées de mandibules. Le protocole a été validé statistiquement. La variabilité globale chez les hominidés, le développement puis la variabilité interspécifique sont analysés.La méthodologie employée procure un gain d'acuité sur le développement mandibulaire et en permet la modélisation. La mandibule subit non pas une évolution globale, mais en mosaïque. Notre méthode permet de distinguer une mandibule antérieure et une mandibule postérieure reliées par l'axe neural. Notre travail confirme le rôle primordial de l'axe neural dans la variabilité mandibulaire. Ses implications phylogénétiques, adaptationnelles et développementales sont envisagées / The mandible is composed of distinct units integrated into a single bone around the director axis of the mandibular nerve which osseous artefact is the mandibular canal.Our study of the evolution and development of the mandible in hominids use a method that permits the study of the individual developments in these sub-units, with the mandibular canal as reference system. 453 mandibles of the genera Homo, Pan, Gorilla and some fossil hominid species are studied. Our protocol is based on standardized digital photographs. Its validity is statistically verified. Global variability in hominids, development and interspecific variability are analyzed.Our methodology provides improved perspicacity concerning the phenomena at work during the mandibular development and allows it to be modeled. The evolution of the mandible is not global but follows a ?mosaic? pattern. We differentiate an anterior mandible and a posterior mandible linked by the neural axis.Our work confirms the primordial, central and leading role of the mandibular nerve in mandibular development. The phylogenetic, adaptational, developmental and therapeutic implications are discussed

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