Hydrogen isotopic composition of sediment cores from a transect off western Africa

The hydrogen isotopic composition of plant leaf-wax n-alkanes (dDwax) is a novel proxy for estimating dD of past precipitation (dDp). However, vegetation life-form and relative humidity exert secondary effects on dDwax, preventing quantitative estimates of past dDp. Here, we present an approach for removing the effect of vegetation-type and relative humidity from dDwax and thus for directly estimating past dDp. We test this approach on modern day (late Holocene; 0-3 ka) sediments from a transect of 9 marine cores spanning 21°N-23°S off the western coast of Africa. We estimate vegetation type (C3 tree versus C4 grass) using d13C of leaf-wax n-alkanes and correct dDwax for vegetation-type with previously-derived apparent fractionation factors for each vegetation type. Late Holocene vegetation-corrected dDwax (dDvc) displays a good fit with modern-day dDp, suggesting that the effects of vegetation type and relative humidity have both been removed and thus that dDvc is a good estimate of dDp. We find that the magnitude of the effect of C3 tree - C4 grass changes on dDwax is small compared to dDp changes. We go on to estimate dDvc for the mid-Holocene (6-8 ka), the Last Glacial Maximum (LGM; 19-23 ka) and Heinrich Stadial 1 (HS1; 16-18.5 ka). In terms of past hydrological changes, our leaf-wax based estimates of dDp mostly reflect changes in wet season intensity, which is complementary to estimates of wet season length based on leaf-wax d13C.

Africa, ca. 1865 (Image 1 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Stanford's library map of Africa, constructed by A. Keith Johnston. It was published by Edward Stanford ca. 1865. Scale 1:5,977,382. This layer is image 1 of 4 total images of the four sheet source map, representing the southwest portion of the map. Covers also a small portion of Europe and the Middle East. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Sinusoidal projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, selected buildings and historical points of interest, territorial boundaries, shoreline features, and more. Relief shown by hachures. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Africa, ca. 1865 (Image 2 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Stanford's library map of Africa, constructed by A. Keith Johnston. It was published by Edward Stanford ca. 1865. Scale 1:5,977,382. This layer is image 2 of 4 total images of the four sheet source map, representing the southeast portion of the map. Covers also a small portion of Europe and the Middle East. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Sinusoidal projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, selected buildings and historical points of interest, territorial boundaries, shoreline features, and more. Relief shown by hachures. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Africa, ca. 1865 (Image 3 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Stanford's library map of Africa, constructed by A. Keith Johnston. It was published by Edward Stanford ca. 1865. Scale 1:5,977,382. This layer is image 3 of 4 total images of the four sheet source map, representing the northeast portion of the map. Covers also a small portion of Europe and the Middle East. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Sinusoidal projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, selected buildings and historical points of interest, territorial boundaries, shoreline features, and more. Relief shown by hachures. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Africa, ca. 1865 (Image 4 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Stanford's library map of Africa, constructed by A. Keith Johnston. It was published by Edward Stanford ca. 1865. Scale 1:5,977,382. This layer is image 4 of 4 total images of the four sheet source map, representing the northwest portion of the map. Covers also a small portion of Europe and the Middle East. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Sinusoidal projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, railroads, selected buildings and historical points of interest, territorial boundaries, shoreline features, and more. Relief shown by hachures. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

The capitals of the globe : the political, commercial, artistic and sacred capitals of Europe, Asia, Africa, North America, South America and the West Indies with graphic and accurate descriptions of all their wonders, shrines, traditions, sensations and treasures ; their political and commercial importance ; their religious, artistic and climatic attractions ; their geographical positions, physical features, history, population, industries, trade, traffic, currency, communications and hotels : the manners and customs of the inhabitants-types and costumes together with every information how to reach them, how to travel, and what it costs : superbly and profusely illustrated with engravings and color maps /

pt. 1. The capitals of Europe -- pt. 2. The capitals of Asia -- pt. 3. The capitals of Africa -- pt. 4. The capitals of North America -- pt. 5. The capitals of Central America, South America and the West Indes.

From stability to insurgency: The root and proximate causes of the September 2002 civil war in Côte d'Ivoire

This dissertation was an analysis of the root and proximate causes of the September 2002 civil war in Côte d’Ivoire. The central question of this study was: Why did Côte d’Ivoire, which was relatively stable under President Houphouët-Boigny, suddenly begin to experience political violence in the 1990s and an explosion in 2002? Côte d’Ivoire was an interesting case because it was stable for a long period of time, apparently making it an infertile ground for conflict. It was also interesting for comparative purposes because of the fact that several states in West Africa (for instance, Benin, Togo, and Ghana) have experienced military coups but not have civil wars. Finally, this case was an opportunity to revisit the debate on the causes of civil wars in the African context. Chapter one has outlined the entire dissertation project and contextualized the analysis that follows in the subsequent chapters. Chapter two has reviewed the literature on civil wars in general, identified the different types of civil wars, and the type the Ivoiran war is. Chapter three has examined the domestic and international political economy as a source of the civil violence in Côte d’Ivoire. Chapter four has examined the role of ethnicity and region as identities of the war, while chapter five has analyzed the role of the foreign relations in the civil war, as well as the regional political context. Chapter six has distinguished between the root and proximate causes of the Ivoirian civil war, made judgments about the relative weight of the various causes, and the extent to which the weight of the causes can be measured. The study found that the “Ivoirité” was the most important trigger of the civil war in Côte d’Ivoire. The overall conclusion of my dissertation was that the September 2002 crisis in that country was a political crisis which occured in the context of a political reform. It first started with succession problems in 1993 followed by the controversial elections in 1995 and 2000. Later, this electoral politics spread beyond electoral issues, namely citizenship matters.

From Stability to Insurgency: The Root and Proximate Causes of the September 2002 Civil War in Cote d'Ivoire

This dissertation was an analysis of the root and proximate causes of the September 2002 civil war in Côte d’Ivoire. The central question of this study was: Why did Côte d’Ivoire, which was relatively stable under President Houphouët-Boigny, suddenly begin to experience political violence in the 1990s and an explosion in 2002? Côte d’Ivoire was an interesting case because it was stable for a long period of time, apparently making it an infertile ground for conflict. It was also interesting for comparative purposes because of the fact that several states in West Africa (for instance, Benin, Togo, and Ghana) have experienced military coups but not have civil wars. Finally, this case was an opportunity to revisit the debate on the causes of civil wars in the African context. Chapter one has outlined the entire dissertation project and contextualized the analysis that follows in the subsequent chapters. Chapter two has reviewed the literature on civil wars in general, identified the different types of civil wars, and the type the Ivoiran war is. Chapter three has examined the domestic and international political economy as a source of the civil violence in Côte d’Ivoire. Chapter four has examined the role of ethnicity and region as identities of the war, while chapter five has analyzed the role of the foreign relations in the civil war, as well as the regional political context. Chapter six has distinguished between the root and proximate causes of the Ivoirian civil war, made judgments about the relative weight of the various causes, and the extent to which the weight of the causes can be measured. The study found that the “Ivoirité” was the most important trigger of the civil war in Côte d’Ivoire. The overall conclusion of my dissertation was that the September 2002 crisis in that country was a political crisis which occured in the context of a political reform. It first started with succession problems in 1993 followed by the controversial elections in 1995 and 2000. Later, this electoral politics spread beyond electoral issues, namely citizenship matters.

Economic Development and Mass Poverty in Africa: Assessment of the Nigerian Experience

The forces surrounding the emerging economies of underdeveloped world, especially Africa has practically stifled its economic progress, growth, development and sustainability. This economic condition brings to the fore the massive onslaught of rural/urban poverty which the African continent grapples with since the post-world war II era to date. The economic misfortunes and incidence of mass poverty in Africa, vis-à-vis Nigeria is used as a point of departure in this study. The paper underscores the ideological and philosophical undertone of international capital manifesting in form of colonialism and imperialism as a major character in the historical process of underdevelopment and mass poverty in peripheral states of Africa, Asia and Latin America, respectively. Of particular interest in this study is the activities of domestic bourgeoisie elite class who have vigorously displayed some degree of lack of much needed vision and abject lack of desires to draw up workable plans to redeem the battered image of African/ Nigerian economic misfortunes. This state of affairs has practically engendered economic underdevelopment, misery and disturbing levels of poverty in the nation-state system. The paper concludes with the forward towards realizing the vision 20-20-20 objectives in the 21t century and beyond.

Differential expression of microRNAs in mouse pain models

Background: MicroRNAs (miRNAs) are short non-coding RNAs that inhibit translation of target genes by binding to their mRNAs. The expression of numerous brain-specific miRNAs with a high degree of temporal and spatial specificity suggests that miRNAs play an important role in gene regulation in health and disease. Here we investigate the time course gene expression profile of miR-1, -16, and -206 in mouse dorsal root ganglion (DRG), and spinal cord dorsal horn under inflammatory and neuropathic pain conditions as well as following acute noxious stimulation. Results: Quantitative real-time polymerase chain reaction analyses showed that the mature form of miR-1, -16 and -206, is expressed in DRG and the dorsal horn of the spinal cord. Moreover, CFA-induced inflammation significantly reduced miRs-1 and -16 expression in DRG whereas miR-206 was downregulated in a time dependent manner. Conversely, in the spinal dorsal horn all three miRNAs monitored were upregulated. After sciatic nerve partial ligation, miR-1 and -206 were downregulated in DRG with no change in the spinal dorsal horn. On the other hand, axotomy increases the relative expression of miR-1, -16, and 206 in a time-dependent fashion while in the dorsal horn there was a significant downregulation of miR-1. Acute noxious stimulation with capsaicin also increased the expression of miR-1 and -16 in DRG cells but, on the other hand, in the spinal dorsal horn only a high dose of capsaicin was able to downregulate miR-206 expression. Conclusions: Our results indicate that miRNAs may participate in the regulatory mechanisms of genes associated with the pathophysiology of chronic pain as well as the nociceptive processing following acute noxious stimulation. We found substantial evidence that miRNAs are differentially regulated in DRG and the dorsal horn of the spinal cord under different pain states. Therefore, miRNA expression in the nociceptive system shows not only temporal and spatial specificity but is also stimulus-dependent.

Structure of an Odorant-Binding Protein from the Mosquito Aedes aegypti Suggests a Binding Pocket Covered by a pH-Sensitive ""Lid""

Background: The yellow fever mosquito, Aedes aegypti, is the primary vector for the viruses that cause yellow fever, mostly in tropical regions of Africa and in parts of South America, and human dengue, which infects 100 million people yearly in the tropics and subtropics. A better understanding of the structural biology of olfactory proteins may pave the way for the development of environmentally-friendly mosquito attractants and repellents, which may ultimately contribute to reduction of mosquito biting and disease transmission. Methodology: Previously, we isolated and cloned a major, female-enriched odorant-binding protein (OBP) from the yellow fever mosquito, AaegOBP1, which was later inadvertently renamed AaegOBP39. We prepared recombinant samples of AaegOBP1 by using an expression system that allows proper formation of disulfide bridges and generates functional OBPs, which are indistinguishable from native OBPs. We crystallized AaegOBP1 and determined its three-dimensional structure at 1.85 angstrom resolution by molecular replacement based on the structure of the malaria mosquito OBP, AgamOBP1, the only mosquito OBP structure known to date. Conclusion: The structure of AaegOBP1 (= AaegOBP39) shares the common fold of insect OBPs with six alpha-helices knitted by three disulfide bonds. A long molecule of polyethylene glycol (PEG) was built into the electron-density maps identified in a long tunnel formed by a crystallographic dimer of AaegOBP1. Circular dichroism analysis indicated that delipidated AaegOBP1 undergoes a pH-dependent conformational change, which may lead to release of odorant at low pH (as in the environment in the vicinity of odorant receptors). A C-terminal loop covers the binding cavity and this ""lid"" may be opened by disruption of an array of acid-labile hydrogen bonds thus explaining reduced or no binding affinity at low pH.

The Mesozoic and Cenozoic motion of Adria (central Mediterranean): a review of constraints and limitations

This paper presents kinematic analysis on the motion of Adria, which is the continental mass that bridges Africa and Europe in the central Mediterranean. Palaeomagnetic data show a general coherence between the motion of Adria and Africa since the Late Paleozoic. This mutual motion, for the period from 120 Ma and the present, is verified by comparing inferred palaeolatitudes from relatively stable parts of Adria (Apulia, Gargano, Istria, and the Southern Alps) and the Hyblean Plateau, with latitudinal changes that are calculated from the motion of Africa with respect to hotspots. Additional constraints on the motion of Adria are provided from the Late Paleozoic-Early Mesozoic passive margin of Adria in the Ionian Sea. The seismic structure of the floor of the Ionian Sea resembles the structure of the oceanic crust in marginal back-arc basins, suggesting that it formed as a small ocean basin. Furthermore, the Ionian lithosphere in the Calabrian arc has been subjected to rapid rollback, which commonly occurs only when the subducting slab is made of oceanic lithosphere. This oceanic domain marks the Pennian-Triassic to Jurassic plate boundary between Adria and Africa, suggesting that a small amount of independent motion between Adria and Africa took place at that time. Since the Jurassic, Adria and Africa have shared a relatively coherent motion path. (C) 2004 Lavoisier SAS. All rights reserved.

Modulation of B-1 and B-2 kinin receptors expression levels in the hippocampus of rats after audiogenic kindling and with limbic recruitment, a model of temporal lobe epilepsy

Epileptic seizures are hypersynchronous, paroxystic and abnormal neuronal discharges. Epilepsies are characterized by diverse mechanisms involving alteration of excitatory and inhibitory neurotransmission that result in hyperexcitability of the central nervous system (CNS). Enhanced neuronal excitability can also be achieved by inflammatory processes, including the participation of cytokines, prostaglandins or kinins, molecules known to be involved in either triggering or in the establishment of inflammation. Multiple inductions of audiogenic seizures in the Wistar audiogenic rat (WAR) strain are a model of temporal lobe epilepsy (TLE), due to the recruitment of limbic areas such as hippocampus and amygdata. In this study we investigated the modulation of the B-1 and B-2 kinin receptors expression levels in neonatal WARs as well as in adult WARs subjected to the TLE model. The expression levels of pro-inflammatory (IL-1 beta) and anti-inflammatory (IL-10) cytokines were also evaluated, as well as cyclooxygenase (COX-2). Our results showed that the B-1 and B-2 kinin receptors mRNAs were up-regulated about 7- and 4-fold, respectively, in the hippocampus of kindled WARs. On the other hand, the expressions of the IL-1 beta, IL-10 and COX-2 were not related to the observed increase of expression of kinin receptors. Based on those results we believe that the B, and B2 kinin receptors have a pivotal role in this model of TLE, although their participation is not related to an inflammatory process. We believe that kinin receptors in the CNS may act in seizure mechanisms by participating in a specific kininergic neurochemical pathway. (c) 2007 Elsevier B.V. All rights reserved.

Analysis of the sequence and expression of a second putative acetylcholinesterase cDNA from organophosphate-susceptible and organophosphate-resistant cattle ticks

The cattle tick, Boophilus microplus, is a major pest of cattle in Australia, Central and South America, and parts of Africa and Asia. Control of ticks with organophosphates (OPs) and carbamates, which target acetylcholinesterases (AChE), led to evolution of resistance to these pesticides. Alleles at the locus studied here, AChE2, from OP-susceptible female ticks from Australia and Mexico differed at 46 of 1689 nucleotide positions (20 putative amino acid differences) whereas alleles from three strains of OP-resistant ticks from Australia differed with the allele from the Australian susceptible ticks at six to 13 nucleotide positions (three to six putative amino acid differences). However, the role, if any, of these polymorphisms in the OP-resistance phenotype is unknown. Certainly none of the polymorphisms correspond to sites in ACK that are involved in catalysis or binding of acetylcholine in other organisms. Both of the AChE loci of B. microplus, AChE1 and AChE2, are apparently expressed in synganglia; AChE1 is also expressed in salivary glands and ovaries, in OP-susceptible and OP-resistant ticks. This seems to contradict studies of enzyme kinetics, which indicated that only one form of AChE was present in the synganglia, the site of the action of OPs, in this species of tick. (C) 2002 Elsevier Science Ltd. All rights reserved.

The road to rulership : Henry Tudor, King of England

At the close of the Wars of the Roses, a new dynasty was founded by a man lacking a prince’s education; moreover, his weak claim to the throne of England gave rise to a set of serious problems. These two crucial, interrelated elements are central in Francis Bacon’s biographical account of Henry VII. The literal road leading Richmond from exile to victory in Bosworth Field, in 1485, is eventually transformed into a metaphoric path that prefigures the long, deep process of learning undertaken during his 24-year reign. This fundamental process carried out by the king will be approached mainly through the passages focused on the Lambert Simnell/Perkin Warbeck affairs, the most difficult probelms the monarch had to face in a time and in a kingdom of many uncertainties. The Simnell/Warbeck menaces embodied Henry Tudor’s greatest dilemmas, continually emphasised in Bacon’s work – the essence of legitimacy and the essence of royalty.