bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of the interfacial activation within the Candida rugosa lipase family
Authors: Pernas María A. , Pastrana Lorenzo , Fuciños Pablo , Rúa M. Luisa
Published: January 2009

The fungus Candida rugosa produces several lipase isoenzymes and the 3D structure of three was solved (Lip1, Lip2 and Lip3). In an aqueous solution, the hydrophobic catalytic cavity of these lipases is buried under a flap that blocks the entrance of the substrate. In the hydrolysis of triacetin, the limiting step of the catalytic process was the activation of the enzyme and only the existence of the highly hydrophobic interface provided by hexane was able to shift the equilibrium towards the open conformation. In the case of Lip1, the hexane interface was crucial and once the open conformation was stabilised, Lip1 was as efficient as Lip3 for the hydrolysis of triacetin. Lip2 isoenzyme behaves more similarly to mLip3 reinforcing the higher structural and functional similarity between these isoenzymes. Inhibition experiments carried out under non‐kinetic conditions allowed to correlate the higher flexibility of the closed flap and the higher hydrophobicity of the catalytic pocket of mLip3 with the greater facility of this isoenzyme to become activated by interfaces of different chemical nature. Both factors might allow a more intense penetration of mLip3 into the interfaces. In these systems, we observed a unique behaviour of Lip2, enzyme that although in a monomeric state and provide with an analogous flap structure to that of Lip1 or Lip3 underwent a very fast activation even in the absence of supramicellar concentrations of surfactants. We determined that the inhibitor itself forms micelles and hypothesised that they might provide an adequate interface for Lip2 activation. Copyright © 2009 John Wiley & Sons, Ltd.
Drilling and installation of boreholes for permafrost thermal monitoring on Livingston Island in the maritime Antarctic
Authors: Ramos Miguel , Hasler Andreas , Vieira Gonzalo , Hauck Christian , Gruber Stephan
Published: January 2009

Three new boreholes up to 25 m deep were drilled on Mount Reina Sofía (275 m a.s.l.), Livingston Island, where previous near‐surface temperature measurements (mean annual ground temperatures of −2.1 to −2.6°C) have indicated the presence of permafrost. A thermistor chain and logging system were installed in the deepest borehole, while the others were equipped with individual miniature temperature loggers (iButtons). Initial data from the 25 m borehole indicates a permafrost body several decametres thick. Future data from these boreholes are expected to provide insight into ground temperature evolution in maritime Antarctica. Copyright © 2009 John Wiley & Sons, Ltd.
Using an F2 screen to monitor frequency of resistance alleles to Bt cotton in field populations of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)
Authors: Xu Zhiping , Liu Fengyi , Chen Jin , Huang Fangneng , Andow David A , Wang Yanhua , Zhu Yu Cheng , Shen Jinliang
Published: January 2009

BACKGROUND: In an effort to control the most devastating cotton pest, Helicoverpa armigera (Hübner), in Qiuxian County (Hebei, China), Bt cotton has been planted almost exclusively since 1998 in this area. Owing to the high insecticidal selection pressures in this region, monitoring of Bt resistance in H. armigera is necessary so that proactive actions can be implemented before field control measures fail. From 2003 to 2005, an F2 screen was conducted in order to monitor Bt resistance in H. armigera populations collected from this area.

RESULTS: The F2 screen showed that 15 out of 278 isofemale lines carried resistance alleles to Bt cotton. The resistance allele frequency in field populations of H. armigera ranged from 0.0119 to 0.0297, with an overall frequency of 0.0146 and a 95% confidence interval of 0.0084–0.0225 for the 3 year period. This value is greater than the value reported from 1999 (P < 0.05).

CONCLUSION: A fluctuating but overall increase in resistance allele frequency was detected in the field populations of H. armigera in Qiuxian County from 1999 to 2005. To prevent further increases in Bt resistance frequency in this pest, it is necessary to introduce Bt cotton expressing multiple Bt toxins and integrate this technology with other tactics for management of this key pest. Copyright © 2009 Society of Chemical Industry
Direct observation of host–guest triplet–triplet annihilation in phosphorescent solid mixed films
Authors: Reineke Sebastian , Schwartz Gregor , Walzer Karsten , Leo Karl
Published: January 2009

Triplet–triplet annihilation (TTA) between excited states of host and guest species in organic mixed films, comprising a phosphorescent heavy‐metal complex, is usually only accessed indirectly, as one is only able to monitor the radiative guest phosphorescence. We compare two different host materials, 4,4′,4″‐tris(N ‐carbazolyl)‐triphenylamine (TCTA) and 4,4′‐N,N ′‐dicarbazole‐biphenyl (CBP) in combination with the green emitter fac ‐tris(2‐phenylpyridine) iridium which differ in their triplet state energy. At excitation levels in the saturation range of guest emission, we observe increasing non‐linearities in photoluminescence transients with increasing excitation power for the CBP host material, which can directly be attributed to TTA of host and guest excited states. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pycnogenol® efficiency on glycaemia, motor nerve conduction velocity and markers of oxidative stress in mild type diabetes in rats
Authors: Jankyova S. , Kucera P. , Goldenberg Z. , Yaghi D. , Navarova J. , Kyselova Z. , Stolc S. , Klimas J. , Racanska E. , Matyas S.
Published: January 2009

The aim of this study was to describe the effects of Pycnogenol® at various doses on preprandial and postprandial glucose levels, the levels of thiobarbituric acid reactive substances (TBARs) and N‐acetyl‐β‐d‐glucosaminidase (NAGA) and on motor nerve conduction velocity (MNCV) in streptozotocin (STZ)‐induced diabetic rats. Pycnogenol® treatment (10, 20, 50 mg/kg body weight (b.w.)/day) lasted for 8 weeks after induction of diabetes.

Pycnogenol® significantly decreased elevated levels of preprandial glycaemia in treated animals at all doses. At doses of 10 mg/kg b.w./day and 20 mg/kg b.w./day it significantly decreased elevated levels of postprandial glycaemia compared with diabetic non‐treated animals. Pycnogenol® failed to induce a significant decrease of postprandial glycaemia at a dose of 50 mg/kg b.w./day.

Pycnogenol® improved significantly the impaired MNCV at doses of 10 and 20 mg/kg b.w./day compared with non‐treated animals.

The levels of TBARs were elevated in diabetic rats. The levels of NAGA increased gradually despite the treatment. Pycnogenol® failed to affect the increased levels of TBARs and NAGA.

Pycnogenol® lowered the elevated levels of glycaemia and reduced the decline in motor nerve conduction velocity in STZ‐induced diabetic rats. The effect of Pycnogenol® on postprandial glycaemic levels and MNCV was not dose‐dependent. Copyright © 2009 John Wiley & Sons, Ltd.
The specific isolation of C‐terminal peptides of proteins through a transamination reaction and its advantage for introducing functional groups into the peptide
Authors: Sonomura Kazuhiro , Kuyama Hiroki , Matsuo Ei‐ichi , Tsunasawa Susumu , Nishimura Osamu
Published: January 2009

A novel method for isolating C‐terminal peptides from proteolytic digests of proteins was developed. Proteins were digested with lysyl endopeptidase (LysC) and applied to metal‐ion‐catalyzed transamination reactions. This reaction enabled the selective conversion of an Nα‐amino group to a carbonyl group. Subsequent incubation with p‐phenylenediisothiocyanate (DITC) glass effectively scavenged the lysine‐containing N‐terminus and internal peptides. The obtained C‐terminal peptide is open to modification with reagents having virtually any type of functionality owing to the reactive α‐ketocarbonyl group. In this report, 2,4‐dinitrophenylhydrazine (DNPH) was used as an example of a nucleophile to the carbonyl group. The isolated C‐terminal peptide was modified with DNPH, which exhibited signal enhancement, and was sequenced by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS). Copyright © 2009 John Wiley & Sons, Ltd.
Crystallinity and Rheological Properties of Pregelatinized Rice Starches Differing in Amylose Content
Authors: Nakorn Kuenchan Na , Tongdang Taewee , Sirivongpaisal Piyarat
Published: January 2009

Three rice starches with different amylose contents (Glutinous: 1.4%, Jasmine: 15.0% and Chiang: 20.2%) were pregelatinized in a double drum dryer at 110, 117 and 123°C. Starch crystallinity was determined by X‐ray diffractometry and Fourier transform infrared (FTIR) spectrometry. Rheological properties were assessed by a Rapid Visco Analyser (RVA) and rheometer. Pregelatinized starches obtained from Glutinous (PGS) and Jasmine rice (PJS) gave an RVA pasting profile with cold peak viscosity. At drum temperature 110°C, PGS and PJS showed X‐ray patterns that were indicative of amorphous structures. However, pregelatinized Chiang rice starch (PCS) exhibited RVA hot peak viscosity and the presence of an amylose‐lipid complex with remaining granule structure. The PCS had a lower water absorption index (WAI) and water solubility index (WSI) than PJS and PGS. After pregelatinization at increased drum temperature (117, 123°C), the PGS had a lower WAI, whereas PCS showed an opposite trend indicating lower degree of granule disruption. In addition, the cold peak viscosity of PGS and PJS decreased with increasing drum temperature. For all drum temperatures, the apparent viscosity at 25°C for PGS and PJS decreased with increasing shear rate, indicating shear‐thinning behavior.
Physicochemical Properties of Oxidized Cassava Starch Prepared under Various Alkalinity Levels
Authors: Sangseethong Kunruedee , Lertphanich Sirithorn , Sriroth Klanarong
Published: January 2009

The physicochemical properties of hypochlorite‐oxidized cassava starch as influenced by the alkalinity levels (pH 8 to 11) during modification process were investigated. Hypochlorite oxidation generally increased the contents of carbonyl and carboxyl groups in starch but decreased starch viscosity. The formation of carbonyl and carboxyl groups was more favorable under the milder alkaline conditions (pH 8 and 9). Oxidation conducted at higher alkalinity levels produced both functional groups at a much slower rate and to a lesser extent. Starch viscosity decreased markedly with increasing reaction time. The alkalinity levels during the modification process greatly influenced the initial viscosity of the oxidized starch paste and the viscosity stability of the paste during storage. Thermal behavior studies by differential scanning calorimetry (DSC) demonstrated that oxidation decreased both gelatinization temperature and enthalpy. The decrease in gelatinization temperature was strongly related to the carboxyl group content. The more carboxyl groups the oxidized starch contained, the lower was the gelatinization temperature. Retrogradation of amylopectin tended to increase slightly after oxidation. While the light transmittance of native starch paste drastically decreased during cold storage, the changes observed in oxidized starch pastes were less pronounced and appeared to depend on carboxyl content. The results from light transmittance studies suggested that carboxyl groups introduced into the starch molecules could effectively prevent retrogradation.
Endoplasmic reticulum may not be involved in the lead‐induced apoptosis in PC 12 cells in vitro
Authors: Xu Jin , Ji Lin‐Dan , Xu Li‐Hong
Published: January 2009

Recent researches indicated that mitochondrial pathway might play an important role in lead‐induced apoptosis. Our previous study also found that lead could induce apoptosis in PC 12 cells, and mitochondrial pathway events were involved in this process. As lead can disturb Ca2+ homeostasis, the present study was undertaken to determine whether lead can activate key cellular events in the endoplasmic reticulum (ER) pathway, including the expressions of C/EBP homology protein (CHOP) and glucose‐regulated protein 78 (GRP78), and the activation of caspase‐12 and calpain. The results showed that lead could increase the expression of GRP78, while the expressions of CHOP and procaspase‐12 remained unchanged. Moreover, the caspase‐12 and calpain were not activated, and the ultrastructure of endoplasmic reticulum was not altered. Therefore, it suggests that lead may induce apoptosis in PC 12 cells through mitochondrial pathway, but not through the endoplasmic reticulum pathway. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010.
Effect of electron beam irradiation on the properties of ethylene‐(vinyl acetate) copolymer/natural rubber/organoclay nanocomposites
Authors: Munusamy Y. , Ismail H. , Mariatti M. , Ratnam C.T.
Published: January 2009

The effects of electron beam (EB) irradiation on the morphology, crosslink density, and tensile properties of EVA/SMR L (Standard Malaysian Rubber)/organoclay nanocomposites prepared by a melt‐blending technique were investigated. All the samples were irradiated by using a 3.0‐MeV EB apparatus with doses ranging from 50 to 200 kGy. Organoclay loading was varied from 0 to 10 phr (parts by weight per hundred parts of resin). X‐ray diffraction results and transmission electron microscopy images proved that the dispersion of organoclay in the nanocomposites was slightly improved by EB irradiation. The gel fraction yield for the nanocomposites increased with irradiation dose but decreased with organoclay loading. However, at 200 kGy, the gel fraction yield was almost the same at all organoclay loadings. Tensile strength and stress at 100% elongation increased proportionally with the irradiation dose. Elongation at break of the nanocomposites increased up to 100 kGy but then decreased at higher irradiation doses. The intercalation and exfoliation of the organoclay, the barrier effect, and the Hofmann degradation of the modification agent are the three major factors leading to the improvement of the properties of the irradiated nanocomposites. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers
A comparison of methodologies for monthly wind energy estimation
Authors: García‐Bustamante E. , González‐Rouco J. F. , Jiménez P. A. , Navarro J. , Montávez J. P.
Published: January 2009

Monthly wind energy estimations obtained by means of three different methodologies are evaluated. Hourly wind and wind power production data measured at five wind farms in the Northeast of Spain within the period spanning from June 1999 to June 2003 were employed for this purpose. One of the approaches is based on the combined contribution of the hourly wind speed frequency distribution and the corresponding power production. Several alternatives to represent the empirical wind power versus wind speed relationship are considered and their impacts on the error of monthly energy estimations assessed. Two more approaches derive monthly energy estimates directly from monthly wind values: one uses the theoretical power curve to obtain interpolated monthly wind power production values and the other consists in a simple linear regression between the observed wind speed and wind power monthly pairs, which serves as an approximation to the global power curve. The three methodologies reproduce reliably the total monthly wind energy. Results also reveal that linearity is a reasonable assumption for the relation between wind speed and power production at monthly timescales. This approach involves a simplification with respect to other standard procedures that require finer temporal resolution data. Copyright © 2009 John Wiley & Sons, Ltd.
Improved tools for efficient mapping of fission yeast genes: identification of microtubule nucleation modifier mod22‐1 as an allele of chromatin‐ remodelling factor gene swr1
Authors: Anders Andreas , Watt Stephen , Bähler Jürg , Sawin Kenneth E.
Published: January 2009

Fission yeast genes identified in genetic screens are usually cloned by transformation of mutants with plasmid libraries. However, for some genes this can be difficult, and positional cloning approaches are required. The mutation swi5‐39 reduces recombination frequency in homozygous crosses and has been used as a tool in mapping gene position (Schmidt, 1993). However, strain construction in swi5‐39‐based mapping is significantly more laborious than is desirable. Here we describe a set of strains designed to make swi5‐based mapping more efficient and more powerful. The first improvement is the use of a swi5Δ strain marked with kanamycin (G418) resistance, which greatly facilitates identification of swi5 mutants. The second improvement, which follows directly from the first, is the introduction of a large number of auxotrophic markers into mapping strains, increasing the likelihood of finding close linkage between a marker and the mutation of interest. We combine these new mapping strains with a rec12Δ‐based approach for initial mapping of a mutation to an individual chromosome. Together, the two methods allow an approximate determination of map position in only a small number of crosses. We used these to determine that mod22‐1, a modifier of microtubule nucleation phenotypes, encodes a truncation allele of Swr1, a chromatin‐remodelling factor involved in nucleosomal deposition of H2A.Z histone variant Pht1. Expression microarray analysis of mod22‐1, swr1Δ and pht1Δ cells suggests that the modifier phenotype of mod22‐1 mutants may be due to small changes in expression of one or more genes involved in tubulin function. Copyright © 2009 John Wiley & Sons, Ltd.
Coding repeat instability in the FLO11 gene of Saccharomyces yeasts
Authors: Fidalgo Manuel , Barrales Ramon R. , Jimenez Juan
Published: January 2009

In Saccharomyces yeasts, the FLO11 gene encodes an adhesin involved in filamentation, invasive growth, flocculation and adherence to solid surfaces. In wild Saccharomyces flor yeasts, a particularly expanded FLO11 allele also confers to these yeasts the ability to float under stressing liquid environments. We report here that, under optimal laboratory conditions, the repeats domain of the FLO11 gene in these wild yeasts is extremely unstable. Changes in length in the FLO11 coding repeats domain affected Flo11p‐associated functions but, interestingly, some of these functions were affected more than others. Therefore, length variations in this single gene provide a combinatorial diversity, which may contribute to a very rapid adaptation to fluctuating environments. Functional analysis of contracted alleles indicated that buoyancy was not associated to FLO11 length. In contrast, this property depended on the different types of repetitive units found in this gene. Thus, not only variations in the number of intragenic repeats but also the abundance and/or distribution of the different repetitive units may have phenotypic and evolutionary implications. Copyright © 2009 John Wiley & Sons, Ltd.
Flocculation in Saccharomyces cerevisiae is repressed by the COMPASS methylation complex during high‐gravity fermentation
Authors: Dietvorst Judith , Brandt Anders
Published: January 2009

The significance of COMPASS on silencing of the FLO and MAL genes, located close to telomeres, was studied in different Saccharomyces cerevisiae strains that fermented high concentrations of maltose (20%) with different efficiency. In one particular fast maltose‐fermenting yeast strain, with constitutive expression of FLO11, the expression of FLO1, FLO5 and FLO9 was induced during fermentation of high concentrations of maltose or glucose. In another strain the expression of mainly FLO1 was induced. Mutants of these strains with a defective COMPASS, however, formed very large aggregates of cells earlier in the fermentation and more pronounced than the wild‐type. The formation of the large flocs was dependent on calcium ions and was inhibited by mannose. The flocculation displayed by mutants defective in COMPASS was due to increased amounts of FLO1, FLO5 and FLO9 transcripts. COMPASS‐mediated silencing of the MAL genes was detected at the later stages of fermentation in strains that fermented high concentrations of maltose slowly and incompletely, while silencing was not detectable in strains that fermented maltose fast. Thus, COMPASS, in addition to the MAL genes, is also involved in silencing the expression of the FLO1, FLO5 and FLO9 genes. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of the S288c genetic background and common auxotrophic markers on mitochondrial DNA function in Saccharomyces cerevisiae
Authors: Young M. J. , Court D. A.
Published: January 2009

Saccharomyces cerevisiae is a valuable model organism for the study of eukaryotic processes. Throughout its development as a research tool, several strain backgrounds have been utilized and different combinations of auxotrophic marker genes have been introduced into them, creating a useful but non‐homogeneous set of strains. The ade2 allele was used as an auxotrophic marker, and for ‘red–white’ screening for respiratory competence. his3 alleles that influence the expression of MRM1 have been used as selectable markers, and the MIP1[S] allele, found in the commonly used S228c strain, is associated with mitochondrial DNA defects. The focus of the current work was to examine the effects of these alleles, singly and in combination, on the maintenance of mitochondrial function. The combination of the ade2 and MIP1[S] alleles is associated with a slight increase in point mutations in mitochondrial DNA. The deletion in the his3Δ200 allele, which removes the promoter for MRM1, is associated with loss of respiratory competence at 37 °C in the presence of either MIP1 allele. Thus, multiple factors can contribute to the maintenance of mitochondrial function, reinforcing the concept that strain background is an important consideration in both designing experiments and comparing results obtained by different research groups. Copyright © 2009 John Wiley & Sons, Ltd.
Type of activity and fitness benefits as moderators of the effect of physical activity on affect in advanced age: a review
Authors: Netz Yael
Published: January 2009

This study aimed to review studies exploring the effect of physical activity on affect in advanced age with a special focus on the moderating role of fitness improvement and mode of exercise and to examine those studies in relation to the potential mechanisms for explaining the physical activity–affect relationship. Studies were assembled through a computer search of online psychological, medical, and exercise science databases. Randomized controlled studies having as their purpose the examination of physical activity effects on affect, with a mean sample population age of at least 50 years, were included. Thirty-nine studies were collated and divided into three groups: those applying aerobic activity, those applying strength training, and those applying non-specific physical activity. The main finding was that aerobic exercise and aerobic fitness do not moderate the effect of physical activity on affect. While fewer than 50% of the aerobic studies reporting fitness improvement also reported improvement in affect, over 50% of the strength training studies and of the non-specific exercise studies reported improvement in affect. Theories with a physiological orientation claiming that aerobic fitness is the mediator between physical activity and affect are not supported, whereas theories with a psychological orientation maintaining that alterations in affect are not dependent on physiological alterations do receive support. It is argued that the differentiation between physiologically and psychologically oriented theories is arbitrary. It is recommended that the relationship between physical activity and affect be explored further, embracing a psychophysiological perspective in which the psychological and physiological perspectives are complementary.
Double In Situ Approach for the Preparation of Polymer Nanocomposite with Multi-functionality
Authors: Wang De-Yi , Song Yan-Peng , Wang Jun-Sheng , Ge Xin-Guo , Wang Yu-Zhong , Stec Anna A , Richard Hull T
Published: January 2009

A novel one-step synthetic route, the double in situ approach, is used to produce both TiO2nanoparticles and polymer (PET), and simultaneously forming a nanocomposite with multi-functionality. The method uses the release of water during esterification to hydrolyze titanium (IV) butoxide (Ti(OBu)4) forming nano-TiO2in the polymerization vessel. This new approach is of general significance in the preparation of polymer nanocomposites, and will lead to a new route in the synthesis of multi-functional polymer nanocomposites.
Analysis of the nucleoside triphosphatase, RNA triphosphatase, and unwinding activities of the helicase domain of dengue virus NS3 protein
Authors: Wang Chun-Chung , Huang Zhi-Shun , Chiang Pei-Ling , Chen Chien-Tsun , Wu Huey-Nan
Published: January 2009

The helicase domain of dengue virus NS3 protein (DENV NS3H) contains RNA‐stimulated nucleoside triphosphatase (NTPase), ATPase/helicase, and RNA 5′‐triphosphatase (RTPase) activities that are essential for viral RNA replication and capping. Here, we show that DENV NS3H unwinds 3′‐tailed duplex with an RNA but not a DNA loading strand, and the helicase activity is poorly processive. The substrate of the divalent cation‐dependent RTPase activity is not restricted to viral RNA 5′‐terminus, a protruding 5′‐terminus made the RNA 5′‐triphosphate readily accessible to DENV NS3H. DENV NS3H preferentially binds RNA to DNA, and the functional interaction with RNA is sensitive to ionic strength.
Cell surface sialylation and fucosylation are regulated by the cell recognition molecule L1 via PLCγ and cooperate to modulate embryonic stem cell survival and proliferation
Authors: Li Ya-Li , Wu Guang-Zhi , Zeng Li , Dawe Gavin S. , Sun Li , Loers Gabriele , Tilling Thomas , Cui Shu-sen , Schachner Melitta , Xiao Zhi-Cheng
Published: January 2009

Cell surface glycosylation patterns are markers of cell type and status. However, the mechanisms regulating surface glycosylation patterns remain unknown. Using a panel of carbohydrate markers, we have shown that cell surface sialylation and fucosylation are upregulated in L1‐transfected embryonic stem cells (L1‐ESCs). Consistently, the mRNA levels of sialyltransferase ST6Gal1 and ST3Gal4, and fucosyltransferase FUT9 were significantly increased in L1‐transfected ESCs. Activation of L1 signaling promoted cell survival and inhibited cell proliferation. ShRNAs knocking down FUT9, ST6Gal1 and ST3Gal4 blocked these effects. A phospholipase Cγ (PLCγ) inhibitor and shRNA reduced ST6Gal1, ST3Gal4 and FUT9 mRNA levels in the L1‐ESCs. Thus, embryonic stem cell surface sialylation and fucosylation are regulated via PLCγ by L1, with which they cooperate to modulate cell survival and proliferation.
The Kenya Maasai and the protest phenomenon, 1900–1960
Authors: King Kenneth
Published: January 2009

This article is concerned to show some of the dimensions of political activity amongst the Kenya Maasai in the first half of this century. Primarily, the focus is not on the ‘traditional’ Maasai, but on the small but not insignificant educated group who, despite the restrictions of the Maasai Reserve, participated in the growth of Kenya's modern African politics. Certain crucial events in East Africa—the circumcision crisis, independency in church and school, and the search for higher education—are shown to have important Maasai counterparts. At the same time, some of the stubbornest administrative and missionary problems presented in the development of Maasailand are examined within a historical perspective, and with the aid of Maasai oral materials where possible.
The Compatibility of the Slave and Palm oil Trades in the Bight of Biafra
Authors: Northrup David
Published: January 2009

The rise of the legitimate trade in palm oil in the nineteenth century is often described as following (or due to) a decline in the overseas slave trade. In fact in the most important oil producing region, the Bight of Biafra, the palm oil trade expanded well in advance of any decline in the slave trade and the suppression of the slave trade occasioned no marked increase in the rate of palm oil export growth. It would appear that the direct and indirect effects of the slave trade in this region had created economic conditions which enabled its small farmers to respond so rapidly to external demand for palm oil. The failure to understand the relationship between the slave and the palm oil trades is a result of misunderstanding the relationship between these oil producers and the coastal middlemen.
The Relevance of Spatial Analysis for African Economic History: the Sierra Leone–Guinea System
Authors: Howard Allen M.
Published: January 2009

This article suggests ways in which a spatial perspective is relevant to questions of African economic history prior to formal colonization. Aspects of spatial analysis can help to identify and compare economically dynamic centres and subregions and to understand the qualities of regional and inter-regional systems. Spatial analysis can also illuminate various economic relationships between Africa and Europe; thus it is relevant to such issues as African adaptation to ‘legitimate’ trade and economic dependency. Among the main concepts discussed are central place theory, ‘growth centres’, port gateways, and dendritic marketing systems. The article focuses upon the Sierra Leone–Guinea plain and the larger Sierra Leone–Guinea inter-regional commercial system during the second half of the nineteenth century. Brief comparisons are made with other areas.
Ano Asemã: Mythe et histoire
Authors: Perrot Claude-H.
Published: January 2009

LES Anyi-Ndényé se trouvent à la bordure occidentale du monde akan, dont ils font partie. La langue qu'ils parlent, l'anyi, est différent du twi (ashanti etc.) et fort proche de la langue du Sefwi (Sayie) et de 1'Aowin (ou Awowin), provinces limitrophes du Ghana occidental. Cependant leur langage tambouriné utilise le twi et la majeure partie du vocabulaire politique, définissant le pouvoir et ses détenteurs, provient directement du twi, langue qui n'est connue aujourd'hui que d'une minorité.
The 1912 Wankie Colliery strike
Authors: Van Onselen Charles
Published: January 2009

The strike at the Wankie Colliery in 1912 offers the labour historian of central Africa an opportunity to explore in some depth the economic and social context of an African response within a colonial industry. The system of cheap labour at Wankie periodically combined with severe production pressures to produce outbreaks of scurvy amongst the African miners. In normal years, workers alleviated the need for nutritious food by scouring the surrounding countryside but this was not possible in a drought year. Under drought conditions the outbreak of scurvy, limited access to alternative food resources and the maldistribution of rations within the compound all assumed increased importance. The policies and practices of the acting compound manager and his black compound staff served further to exacerbate tensions in the Wankie compound and precipitate a strike.

Although the strike at Wankie offers further evidence of worker consciousness in early Rhodesian industry the events in the compound should not be interpreted as a sign of real or potential African radicalism. Closer examination of the African responses at Wankie reveal the essentially conservative nature of many of the demands made by the workers. It seems possible that in Rhodesia the power of the state over a colonial political economy and the repressive nature of the compound system combined to inhibit more radical responses. At Wankie, workers questioned the functioning of a repressive system, not the system itself. In many respects events at Wankie were typical of the Rhodesian mining industry and as such the strike serves to illustrate the vulnerable class position of African workers in a colonial economy.
The Italo-Ethiopian conflict: A case study in British West African response to crisis diplomacy in the 1930s
Authors: Asante S. K. B.
Published: January 2009

This article attempts to examine the reaction of the anti-colonial nationalists in British West Africa to the diplomacy of their ruling colonial power with regard to the Italo-Ethiopian crisis of 1935–6. This reaction was largely influenced by the nationalists' claim to special relationship with Britain and their firm belief not only in British power but also in the British ‘gospel of equity and fair-play’. Consequently, when Britain and France, because of their obsession with the need for security, failed to protect the territorial integrity and political independence of the symbolic and sole surviving black empire of Ethiopia, these race- conscious nationalists rashly concluded that there was a concerted plot among the whites against the black race. This belief was reinforced first by the refusal of Britain and France to supply arms to Ethiopia during the conflict; secondly, by the infamous Hoare–Laval peace pact of December 1935, which would have compromised Ethiopia's independence had it been implemented; and thirdly, by British recognition of the Italian conquest of Ethiopia. Disenchantment with the League of Nations, coupled with the disillusionment with the diplomacy of the colonial powers during the crisis, led the articulate nationalists to begin seriously to reconsider their relationship with Britain and the whole doctrine of the ‘civilising mission’. Their nationalism shifted from the idea of working within the trusteeship concept to a more militant anti-white pan-Africanism.
Caudatum sorghums and speakers of Chari-Nile languages in Africa
Authors: Stemler A. B. L. , Harlan J. R. , Dewet J. M. J.
Published: January 2009

Our study of caudatum sorghums in Africa and the ethnography, history, and archaeology of regions where caudatum sorghums are grown has led us to the following conclusions.

The distributions of caudatum sorghums and Chari-Nile-speaking peoples coincide so closely that a causal relationship seems probable.

Caudatum sorghums appear to be a product of selection by Chari-Nile-speaking peoples for a hardy crop which will produce a large amount of grain under adverse conditions with a minimum amount of care. Caudatums can produce grain in spite of either droughts or heavy rains during the growing season and can produce grain in places where no other indigenous African crop can grow.

Caudatum may be a relatively new race of sorghum. Available evidence indicates it was developed some time after about 350 A.D. and before about 900 A.D., the date for caudatum found at Daima mound, south of Lake Chad.

By about 1000 A.D. caudatum was probably being grown in many parts of the savanna belt stretching from the eastern shores of Lake Chad to southwestern Ethiopia. This is assuming that the evidence of caudatum culture at Daima is indicative of a general phenomenon occurring in a region with close intercultural contacts.

The large number of varieties of caudatum in the Republic of the Sudan suggests that caudatum sorghums have been grown in the Sudan for a relatively long time and may have been developed there.

A caudatum and cattle-based economy has probably been an important factor in making possible the present level of occupation of regions now inhabited by Chari-Nile-speaking peoples.

On the basis of oral histories and archaeological remains of people in northern East Africa, we have concluded that caudatum-based agriculture was probably introduced to Uganda and Kenya no later than the period from 1500–1800 A.D., when the Luo occupied the areas in which they live at the present. However, it is not unlikely that caudatums were introduced more than once as various Chari-Nile-speaking groups made their way into East Africa.
The Kisra legend and the distortion of historical tradition
Authors: Stevens Phillips
Published: January 2009

The presence of the ‘Kisra legend’ in certain western Sudanic societies has long puzzled historians and anthropologists. Attempts by many to explain the phenomenon have been seen as unsatisfactory. In Section I of this study we noted the fact that the Arabic Kasra or Kesra, having been derived from the title of one or the other of two Persian kings of the sixth and seventh centuries, denotes, in von Grunebaum's phrase, ‘a truly royal style of life’. The profound influences of Perso-Arabic elements on many cultures of the southern and western Sudan, even before the spread of Islam in these areas, strongly suggests the possibility that, rather than by any specific migration, the idea of ‘Kisra’ was borne across the Sahara, to the areas where it took root in the form of the Kisra legends. When the geographical situation of those societies having fully-developed Kisra legends is considered, noting that the most detailed and strongly held legends obtain among societies who were constantly threatened by others who were recognized as technologically, and possibly felt as culturally, superior, and among whom the Kisra idea also existed, the origins and distribution of such legends becomes more plausibly explainable. It has been suggested that, through a selective altering of historical tradition, over time, societies who felt so threatened were able to (1) assert their equality to, if not superiority over, the threatening power; (2) justify their successful maintenance of independence in spite of this threat; and/or (3) thus re-establish a basis for societal unity.
The vanishing Mpongwe: European contact and demographic change in the Gabon River
Authors: Patterson K. David
Published: January 2009

A drastic decline of aboriginal populations has been an important by-product of European commercial and imperial expansion in many parts of the world. Europeans have been aware of this phenomenon from the early days of Spanish exploration and conquest when Fray Bartolome de las Casas deplored the rapid collapse of Indian populations in the Caribbean. The problem still seemed acute in the nineteenth century. For example, the young Charles Darwin, describing the decline of the Australian Aborigines, placed most of the blame on alcoholism, introduced diseases, and the loss of hunting grounds. But these factors did not fully explain what appeared to be the impending extinction of a variety of peoples. ‘Besides these several evident causes of destruction,’ he wrote,

there appears to be some more mysterious agency at work. Wherever the European has trod, death seems to pursue the aboriginal. We may look to the wide extent of the Americas, Polynesia, the Cape of Good Hope, and Australia, and we find the same result.
Akan stool succession under colonial rule—continuity or change?
Authors: Henige David
Published: January 2009

This paper argues that interpretations which would view pre-colonial Akan political life as ‘normative’ and structured may be incorrect, at least in so far as stool succession is concerned. Contemporaneous evidence for this early period is at best sparse and at worst simply non-existent and seldom allows even tentative hypotheses. Rather, it is necessary to infer past practices from more recent data, whether this be observation of present behaviour or recent testimony about the past. In this case I have used the testimony presented at various stool and jurisdictional disputes during the colonial period for which records survive. These are generally, of course, ex parte statements and can be used only with caution. However, there is a surprising consensus throughout these records that both the principles and the patterns of stool succession and paramountcy in the pre-colonial period were variegated and even extemporaneous although, not surprisingly, there is much dispute about the reasons for this. On balance, this testimony suggests that a re-interpretation of early Akan political culture using a wider range of evidence is desirable.

Although this implies that the impact of colonial ‘indirect’ rule was not as profound as has often been supposed, I have not discussed this problem directly except as it bears on the quality of the data. Nor have I attempted to analyse the day-to-day dynamics of political life, either for the earlier period (which would be impossible on the evidence) or for the colonial period (which would be irrelevant for comparison). Nevertheless, within the restricted compass of stool succession and paramountcy the argument here is that colonial rule involved little fundamental change from earlier practices. If anything, it probably served to delimit a greater range of previous options by seeking to codify them.
Aspects of Turkana Leadership during the Era of Primary Resistance
Authors: Lamphear John
Published: January 2009

After a considerable period of conflict with nineteenth-century traders, hunters and ‘explorers’, the Turkana of northwestern Kenya actively resisted the occupation of their country by the Imperial forces of British East Africa and Uganda during the second and third decades of the twentieth century. At first, this primary resistance was largely in the hands of war-leaders, notably Ebei, the most important military leader of the southern sections. Bitterness engendered by Hut Taxes and other unpopular British policies led to the brief ascendancy of Koletiang, an influential southern diviner, until he was imprisoned in 1911. Again the resistance leadership fell to the military until especially brutal ‘punitive actions’ in 1915 had the effect of consolidating resistance in the north. At this point, Lowalel, another powerful diviner, became the spiritual patron of the war-leaders and their followers, reaffirming the close co-operation which traditionally had existed between religious and military leaders in Turkana society. So charismatic and innovative was Lowalel's leadership that he amassed armies several thousand strong and was joined by other peoples including the Merille and Dongiro, as well as by the forces of the Ethiopian Empire, in resisting the extension of British colonial rule.
The Ashanti Kings in the Eighteenth Century: A Revised Chronology
Authors: Priestley Margaret , Wilks Ivor
Published: January 2009

In studying the early history of the West African states, one of the difficulties encountered is that of establishing a reasonably precise framework of chronology. Eighteenth-century Ashanti, however, would appear to be an exception to this in that the reigns of its kings are dated, although with some degree of variation, in all the standard works dealing with the area. Their authors, from this point of view, have followed either Thomas Edward Bowdich or Joseph Dupuis, both of whom were in Kumasi, the Ashani capital, in the early part of the nineteenth century. In their treatment of traditions and customs, the writings of Bowdich and Dupuis are of great interest and value; the chronologies of the two authors, however, although they contain major differences, can in neither case be regarded as reliable. Fortunately there are in existence written records, hitherto little used, which make it possible to draw up a new and amended chart of the reigns of the eighteenth-century kings, and which furthermore give rise to interesting questions. These are the records of the various European companies engaged in trade on the coast, notably the English Royal African Company (1672–1750), its successor the Company of Merchants trading to Africa (1750–1821), and the second Dutch West Indies Company (1674–1791). Their agents in the forts and settlements were much interested in local developments especially in so far as trade might be beneficially or adversely affected. As a part of their duties, they kept diaries of events and dispatched reports, often of a very detailed nature, to their Companies in London and Amsterdam.
The Archives of Tropical Africa: A Reconnaissance
Authors: Curtin Philip D.
Published: January 2009

As African governments have become richer of late, they have become more interested in their past, and the outside world has become more conscious that there is an African past worth investigating. Out of all these tendencies, colonial governments and newly-independent states alike have begun to put their government documents in order and to open them for historical research. This process of creating regular archives in tropical Africa has moved fast in the last decade, and it is time to begin assessing the consequences—in terms of documents now physically available, and with a view to their possible value as sources for African history.
Ife and its Archaeology
Authors: Willett Frank
Published: January 2009

No general account of the archaeology of Ife has ever been published, although the demand for such an account has been increasing with the growing interest in the art of Ife. This paper attempts to fill the gap by providing a survey of the investigations which have been conducted there. The reader is also referred to a paper by William Fagg and the present author which attempts to summarize the reliable factual knowledge about Ancient Ife, inferring from the archaeological finds evidence of the materials which have not survived. So far as possible repetition here of material contained in that paper is avoided. Moreover, since the archaeologist who works on ethnohistoric problems has other means of investigation than the pick and shovel, this paper will refer to ethnographic accounts as well as to excavations.
The Peoples of Angola in the Seventeenth Century According to Cadornega
Authors: Childs Gladwyn Murray
Published: January 2009

There are a number of accounts of the strange world of Africa as seen by adventurers, explorers, missionaries, soldiers, and traders in the sixteenth, seventeenth, and eighteenth centuries. By piecing together their accounts we can get quite a good picture of the African lands and peoples which they visited. There was only one, however, who attempted to put down a connected history of what took place in Angola during the first century of its history, i.e. beginning with the founding of Luanda in 1576.
Notes on Negro American Influences on the Emergence of African Nationalism
Authors: Shepperson George
Published: January 2009

The claims of no people…are respected by any nation until they are presented in a national capacity. (Martin R. Delany,The Condition, Elevation, Emigration and Destiny of the Colored People of the United States, Politically Considered, Philadelphia, 1852, p. 210.)

…it is not so muchAfro-Americansthat we want asAfricans. (Casely Hayford,Ethiopia Unbound, London, 1911, p. 173.)

…on us too depends in a large degree the attitude of Europe towards the teeming millions of Asia and Africa. (William Edward Burghardt Du Bois, ‘The Present Outlook for the Dark Races of Mankind’,African Methodist Episcopal Church Review, Philadelphia, XVI, 1900, pp. 102–3.)
Field Histories among the Hausa
Authors: Smith M. G.
Published: January 2009

This paper gives an account of field methods used to study the history of Zaria emirate, Northern Nigeria, in 1950. Similar methods were later used in historical studies of Bornu, Sokoto, Kano, Katsina, Daura and Maradi. I hope this procedure may be helpful elsewhere, and to illustrate it shall describe the original inquiry at Zaria, results of which have already been published.
Historical Aspects of Genealogies in Northern Somali Social Structure
Authors: Lewis I. M.
Published: January 2009

Few anthropologists, I think, would question that the use of oral tradition as a historical source in tribal studies requires a knowledge of the part tradition plays in the society in which it occurs. Most would agree that oral tradition does not have a universal validity—it is not equally ‘true’ or equally ‘false’ in all tribal societies. Rather its historical content, where unequivocal historical evidence is lacking, has to be evaluated in the light of the contemporary social situations to which it is related. Since Malinowski, many anthropologists have tended to the view that traditions about the past express the reality of the present more than they record what actually happened in the past. Legends about the past, indeed, have often been described as ‘charters’ validating the present by attributing a respectable antiquity to its origins.