Determinants of seasonal changes in availability of food patches for elephants (Loxodonta africana in a semi-arid African savanna

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Bruce W. Clegg

2017-06-01

Full Text Available Loss of biodiversity caused by impact of elephants (Loxodonta africana on African woodlands may require a management response, but any action should be based on an understanding of why elephants choose to utilise trees destructively. Comprehension of elephant feeding behaviour requires consideration of the relative value of the plant groups they may potentially consume. Profitability of available food is partly determined by the time to locate a food patch and, therefore, as a foundation for understanding the influence of food availability on diet selection, key controls on the density of grass, forb, and browse patches were investigated across space and time in a semi-arid African savanna. Density of food patches changed seasonally because plant life-forms required different volumes of soil water to produce green forage; and woody plants and forbs responded to long-term changes in soil moisture, while grasses responded to short-term moisture pulses. Soil texture, structure of woody vegetation and fire added further complexity by altering the soil water thresholds required for production of green forage. Interpolating between regularly-timed, ground-based measurements of food density by using modelled soil water as the predictor in regression equations may be a feasible method of quantifying food available to elephants in complex savanna environments.

Standing sedation in African elephants (Loxodonta africana) using detomidine-butorphanol combinations.

Science.gov (United States)

Neiffer, Donald L; Miller, Michele A; Weber, Martha; Stetter, Mark; Fontenot, Deidre K; Robbins, P K; Pye, Geoffrey W

2005-06-01

Standing sedation was provided for 14 clinical procedures in three African elephants (Loxodonta africana) managed by combined protected and modified-protected contact and trained through operant conditioning. An initial hand-injection of detomidine hydrochloride and butorphanol tartrate at a ratio of 1:1 on a microg:microg basis was administered intramuscularly, with a dosage range of 50-70 mg (12.9-19.7 microg/kg) for each drug. The initial injection resulted in adequate sedation for initiation and completion of eight procedures, whereas supplemental doses were required for the remaining procedures. The dosage range for the supplemental injections of each drug was 4.0-7.3 microg/kg. Initial effect was noted within 3.0-25 min (mean = 11.6 min, SD +/- 5.9 min), with maximal effect occurring at 25-30 min for those procedures not requiring supplementation. In all but one procedure, this effect was maintained until the end of the procedure, which ranged from 47 to 98 min (mean = 74.7 min, SD +/- 18.8 min). No cardiac or respiratory depression was appreciated. Recovery after administration of reversal agents was rapid and complete, ranging from 2 to 20 min (mean = 9.0 min, SD +/- 7.0 min). On the basis of the authors' experience, recommended dosage ranges for reversal agents would be intravenous yohimbine (73.4-98.5 microg/kg), intravenous naltrexone (48.9-98.5 microg/kg), and intramuscular naltrexone (73.4-98.5 microg/kg). Approximately one-third to one-half of the total naltrexone dose should be administered intravenously. Mild adverse side effects limited to the gastrointestinal tract were observed in association with five procedures including abdominal distention with or without transient anorexia. Administration of reversal agents, encouraging exercise and water consumption, and administration of flunixin meglumine were helpful in the resolution of signs. In addition to gastrointestinal signs, slight ataxia was observed before initiation of surgical stimulation

The impact of male contraception on dominance hierarchy and herd association patterns of African elephants (Loxodonta africana in a fenced game reserve

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L.S. Doughty

2014-12-01

Full Text Available Overpopulation of African elephants (Loxodonta africana in fenced reserves in South Africa is becoming increasingly problematic to wildlife managers. With growing opposition to culling and the high cost of translocation, alternative management strategies focusing on male elephants are being investigated. In this study, hormonal treatment via Gonadotropin Releasing Hormone (GnRH suppression, and surgical treatment via vasectomy were trialled. Focusing on behavioural responses, we tested the male dominance hierarchy for transitivity, and examined the rank order of individuals in relation to age and contraceptive treatment received. Additionally, we studied association patterns between males within the male population and with the female herds.Findings suggest that the treatment of one individual with GnRH suppressant is affecting the rank order of the dominance hierarchy, though it is still transitive, yet fluid (Landau’s linearity index h=0.7, as expected in a normal elephant population. Between males, association patterns were found to be weak. However, some males had relatively strong associations with the female herds, with association indices between 0.25 and 0.41. This suggests that the reduction on births is resulting in the males spending atypically large amounts of time with the female herds. The future conservation implications of this population control mechanism are discussed. Keywords: African elephant, Population control, Contraception, Social dynamics, Dominance, Association patterns

The social and ecological integration of captive-raised adolescent male African elephants (Loxodonta africana into a wild population.

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Kate Evans

Full Text Available BACKGROUND: A rapid rise in the number of captive African elephants (Loxodonta africana used in the tourism industry in southern Africa and orphaned elephants in human care has led to concerns about their long-term management, particularly males. One solution is to release them into the wild at adolescence, when young males naturally leave their herd. However, this raises significant welfare concerns: little is known about how well released elephants integrate into wild populations and whether they pose a greater threat to humans than wild elephants. We document the release of three captive-raised adolescent male African elephants in the Okavango Delta, Botswana. METHODOLOGY/PRINCIPAL FINDINGS: Despite having been part of a herd of working elephants for at least eight years, the three males progressively integrated into the complex fission-fusion society of wild bull elephants. In the three years following release, they showed no tendency to be closer to human habitation, and there were no significant differences between wild and captive-raised adolescent males in the total number of social interactions, size of ranges and habitat use. However, the captive-raised elephants sparred less and vocalised more, and spent more time alone and in smaller social groups. Thereafter the released elephants continued to expand their ranges and interact with both mixed-sex herds and males. One male was shot by farmers 94 months after release, along with ten wild elephants, on a ranch outside the protected area. CONCLUSIONS/SIGNIFICANCE: We show that captive-raised adolescent male elephants can integrate into a wild population. Long-term studies are required to determine the longevity, breeding success, and eventual fate of released male elephants, but we identified no significant short-term welfare problems for the released elephants or recipient population. Release of captive-raised mammals with complex social systems is a husbandry option that should be

Housing and Social Environments of African (Loxodonta africana and Asian (Elephas maximus Elephants in North American Zoos.

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Cheryl L Meehan

Full Text Available We evaluated 255 African (Loxodonta africana and Asian (Elephas maximus elephants living in 68 North American zoos over one year to quantify housing and social variables. All parameters were quantified for the both the day and the night and comparisons were made across these time periods as well as by species and sex. To assess housing, we evaluated not only total exhibit size, but also individual animals' experiences based on the time they spent in the unique environments into which the exhibits were subdivided. Variables developed to assess housing included measurements of area as a function of time (Total Space Experience, environment type (Indoor, Outdoor, In/Out Choice and time spent on hard and soft flooring. Over the year, Total Space Experience values ranged from 1,273 square feet to 169,692 square feet, with Day values significantly greater than Night values (p<0.001. Elephants spent an average of 55.1% of their time outdoors, 28.9% indoors, and 16% in areas with a choice between being in or out. Time spent on hard flooring substrate ranged from 0% to 66.7%, with Night values significantly greater than Day (p<0.001. Social factors included number of animals functionally housed together (Social Experience and social group characteristics such as time spent with juveniles and in mixed-sex groups. Overall Social Experience scores ranged from 1 to 11.2 and were significantly greater during the Day than at Night (p<0.001. There were few significant social or housing differences between African (N = 138 and Asian (N = 117 species or between males (N = 54 and females (N = 201. The most notable exception was Total Space Experience, with African and male elephants having larger Total Space Experience than Asian and female elephants, respectively (P-value<0.05. The housing and social variables evaluated herein have been used in a series of subsequent epidemiological analyses relating to various elephant welfare outcomes.

The mummified brain of a pleistocene woolly mammoth (Mammuthus primigenius) compared with the brain of the extant African elephant (Loxodonta africana).

Science.gov (United States)

Kharlamova, Anastasia S; Saveliev, Sergei V; Protopopov, Albert V; Maseko, Busisiwe C; Bhagwandin, Adhil; Manger, Paul R

2015-11-01

This study presents the results of an examination of the mummified brain of a pleistocene woolly mammoth (Mammuthus primigenius) recovered from the Yakutian permafrost in Siberia, Russia. This unique specimen (from 39,440-38,850 years BP) provides the rare opportunity to compare the brain morphology of this extinct species with a related extant species, the African elephant (Loxodonta africana). An anatomical description of the preserved brain of the woolly mammoth is provided, along with a series of quantitative analyses of various brain structures. These descriptions are based on visual inspection of the actual specimen as well as qualitative and quantitative comparison of computed tomography imaging data obtained for the woolly mammoth in comparison with magnetic resonance imaging data from three African elephant brains. In general, the brain of the woolly mammoth specimen examined, estimated to weigh between 4,230 and 4,340 g, showed the typical shape, size, and gross structures observed in extant elephants. Quantitative comparative analyses of various features of the brain, such as the amygdala, corpus callosum, cerebellum, and gyrnecephalic index, all indicate that the brain of the woolly mammoth specimen examined has many similarities with that of modern African elephants. The analysis provided here indicates that a specific brain type representative of the Elephantidae is likely to be a feature of this mammalian family. In addition, the extensive similarities between the woolly mammoth brain and the African elephant brain indicate that the specializations observed in the extant elephant brain are likely to have been present in the woolly mammoth. © 2015 Wiley Periodicals, Inc.

Housing and Demographic Risk Factors Impacting Foot and Musculoskeletal Health in African Elephants [Loxodonta africana] and Asian Elephants [Elephas maximus] in North American Zoos.

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Michele A Miller

Full Text Available For more than three decades, foot and musculoskeletal conditions have been documented among both Asian [Elephas maximus] and African [Loxodonta africana] elephants in zoos. Although environmental factors have been hypothesized to play a contributing role in the development of foot and musculoskeletal pathology, there is a paucity of evidence-based research assessing risk. We investigated the associations between foot and musculoskeletal health conditions with demographic characteristics, space, flooring, exercise, enrichment, and body condition for elephants housed in North American zoos during 2012. Clinical examinations and medical records were used to assess health indicators and provide scores to quantitate conditions. Using multivariable regression models, associations were found between foot health and age [P value = 0.076; Odds Ratio = 1.018], time spent on hard substrates [P value = 0.022; Odds Ratio = 1.014], space experienced during the night [P value = 0.041; Odds Ratio = 1.008], and percent of time spent in indoor/outdoor exhibits during the day [P value < 0.001; Odds Ratio = 1.003]. Similarly, the main risk factors for musculoskeletal disorders included time on hard substrate [P value = 0.002; Odds Ratio = 1.050] and space experienced in indoor/outdoor exhibits [P value = 0.039; Odds Ratio = 1.037]. These results suggest that facility and management changes that decrease time spent on hard substrates will improve elephant welfare through better foot and musculoskeletal health.

Assessment of Flooring Renovations on African Elephant (Loxodonta africana) Behavior and Glucocorticoid Response

Science.gov (United States)

Boyle, Sarah A.; Roberts, Beth; Pope, Brittany M.; Blake, Margaret R.; Leavelle, Stephen E.; Marshall, Jennifer J.; Smith, Andrew; Hadicke, Amanda; Falcone, Josephine F.; Knott, Katrina; Kouba, Andrew J.

2015-01-01

Captive African (Loxodonta africana) and Asian (Elephas maximus) elephants can experience foot pathologies and arthritis. As a preventative measure against these pathologies and to alleviate the potential discomfort due to concrete substrates, some zoological institutions have renovated elephant housing to increase the amount of natural or shock-absorbent substrates. The objective of this study was to compare behavioral (diurnal and nocturnal) and glucorticoid (e.g., serum cortisol) responses of three female African elephants before, during, and after renovation to their indoor housing floor to assess whether renovations had short-term effects on the elephants’ behavior and stress physiology. Behavioral data were collected using scan-sampling methods, and activity budgets were constructed for each of the three elephants. In addition, the duration of all lying rest activities were recorded. Weekly serum cortisol concentrations were determined with enzyme immunoassay (EIA). Overall, eating was the most prevalent behavior exhibited outdoors during the day, while resting (either in a lying or standing position) were most common during the indoor, nocturnal periods. Although variation existed among the three elephants, all three females spent significantly more time walking and less time eating during the day after the completion of the renovations. The extent to which the three elephants exhibited nocturnal lying rest behavior varied among the elephants, with the oldest elephant exhibiting the least amount (an average of 13.2 ± 2.8% of the nightly behavioral scans) compared to the two younger elephants (an average of 34.5 ± 2.1% and 56.6 ± 2.8% of the nightly behavioral scans). There was a significant increase in lying rest behavior for one elephant and standing rest for a second elephant following renovations. Baseline cortisol concentrations prior to renovations were 3.0 ± 0.4 ng/ml, 4.5 ± 0.5 ng/ml, and 4.9 ± 0.5 ng/ml for the three elephants. Cortisol

Assessment of Flooring Renovations on African Elephant (Loxodonta africana Behavior and Glucocorticoid Response.

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Sarah A Boyle

Full Text Available Captive African (Loxodonta africana and Asian (Elephas maximus elephants can experience foot pathologies and arthritis. As a preventative measure against these pathologies and to alleviate the potential discomfort due to concrete substrates, some zoological institutions have renovated elephant housing to increase the amount of natural or shock-absorbent substrates. The objective of this study was to compare behavioral (diurnal and nocturnal and glucorticoid (e.g., serum cortisol responses of three female African elephants before, during, and after renovation to their indoor housing floor to assess whether renovations had short-term effects on the elephants' behavior and stress physiology. Behavioral data were collected using scan-sampling methods, and activity budgets were constructed for each of the three elephants. In addition, the duration of all lying rest activities were recorded. Weekly serum cortisol concentrations were determined with enzyme immunoassay (EIA. Overall, eating was the most prevalent behavior exhibited outdoors during the day, while resting (either in a lying or standing position were most common during the indoor, nocturnal periods. Although variation existed among the three elephants, all three females spent significantly more time walking and less time eating during the day after the completion of the renovations. The extent to which the three elephants exhibited nocturnal lying rest behavior varied among the elephants, with the oldest elephant exhibiting the least amount (an average of 13.2 ± 2.8% of the nightly behavioral scans compared to the two younger elephants (an average of 34.5 ± 2.1% and 56.6 ± 2.8% of the nightly behavioral scans. There was a significant increase in lying rest behavior for one elephant and standing rest for a second elephant following renovations. Baseline cortisol concentrations prior to renovations were 3.0 ± 0.4 ng/ml, 4.5 ± 0.5 ng/ml, and 4.9 ± 0.5 ng/ml for the three elephants

Assessment of Body Condition in African (Loxodonta africana and Asian (Elephas maximus Elephants in North American Zoos and Management Practices Associated with High Body Condition Scores.

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Kari A Morfeld

Full Text Available Obesity has a negative effect on health and welfare of many species, and has been speculated to be a problem for zoo elephants. To address this concern, we assessed the body condition of 240 elephants housed in North American zoos based on a set of standardized photographs using a 5-point Body Condition Score index (1 = thinnest; 5 = fattest. A multi-variable regression analysis was then used to determine how demographic, management, housing, and social factors were associated with an elevated body condition score in 132 African (Loxodonta africana and 108 Asian (Elephas maximus elephants. The highest BCS of 5, suggestive of obesity, was observed in 34% of zoo elephants. In both species, the majority of elephants had elevated BCS, with 74% in the BCS 4 (40% and 5 (34% categories. Only 22% of elephants had BCS 3, and less than 5% of the population was assigned the lowest BCS categories (BCS 1 and 2. The strongest multi-variable model demonstrated that staff-directed walking exercise of 14 hours or more per week and highly unpredictable feeding schedules were associated with decreased risk of BCS 4 or 5, while increased diversity in feeding methods and being female was associated with increased risk of BCS 4 or 5. Our data suggest that high body condition is prevalent among North American zoo elephants, and management strategies that help prevent and mitigate obesity may lead to improvements in welfare of zoo elephants.

Reproductive Health Assessment of Female Elephants in North American Zoos and Association of Husbandry Practices with Reproductive Dysfunction in African Elephants (Loxodonta africana.

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Janine L Brown

Full Text Available As part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the Association of Zoos and Aquariums and applied epidemiological methods to determine what factors in the zoo environment are associated with reproductive problems, including ovarian acyclicity and hyperprolactinemia. Bi-weekly blood samples were collected from 95 African (Loxodonta africana and 75 Asian (Elephas maximus (8-55 years of age elephants over a 12-month period for analysis of serum progestogens and prolactin. Females were categorized as normal cycling (regular 13- to 17-week cycles, irregular cycling (cycles longer or shorter than normal or acyclic (baseline progestogens, <0.1 ng/ml throughout, and having Low/Normal (<14 or 18 ng/ml or High (≥14 or 18 ng/ml prolactin for Asian and African elephants, respectively. Rates of normal cycling, acyclicity and irregular cycling were 73.2, 22.5 and 4.2% for Asian, and 48.4, 37.9 and 13.7% for African elephants, respectively, all of which differed between species (P < 0.05. For African elephants, univariate assessment found that social isolation decreased and higher enrichment diversity increased the chance a female would cycle normally. The strongest multi-variable models included Age (positive and Enrichment Diversity (negative as important factors of acyclicity among African elephants. The Asian elephant data set was not robust enough to support multi-variable analyses of cyclicity status. Additionally, only 3% of Asian elephants were found to be hyperprolactinemic as compared to 28% of Africans, so predictive analyses of prolactin status were conducted on African elephants only. The strongest multi-variable model included Age (positive, Enrichment Diversity (negative, Alternate Feeding Methods (negative and Social Group Contact (positive as predictors of hyperprolactinemia. In summary, the incidence of ovarian cycle problems and hyperprolactinemia predominantly

Why do African elephants (Loxodonta africana) simulate oestrus? An analysis of longitudinal data.

Science.gov (United States)

Bates, Lucy A; Handford, Rosie; Lee, Phyllis C; Njiraini, Norah; Poole, Joyce H; Sayialel, Katito; Sayialel, Soila; Moss, Cynthia J; Byrne, Richard W

2010-04-07

Female African elephants signal oestrus via chemicals in their urine, but they also exhibit characteristic changes to their posture, gait and behaviour when sexually receptive. Free-ranging females visually signal receptivity by holding their heads and tails high, walking with an exaggerated gait, and displaying increased tactile behaviour towards males. Parous females occasionally exhibit these visual signals at times when they are thought not to be cycling and without attracting interest from musth males. Using demographic and behavioural records spanning a continuous 28-year period, we investigated the occurrence of this "simulated" oestrus behaviour. We show that parous females in the Amboseli elephant population do simulate receptive oestrus behaviours, and this false oestrus occurs disproportionately in the presence of naïve female kin who are observed coming into oestrus for the first time. We compare several alternative hypotheses for the occurrence of this simulation: 1) false oestrus has no functional purpose (e.g., it merely results from abnormal hormonal changes); 2) false oestrus increases the reproductive success of the simulating female, by inducing sexual receptivity; and 3) false oestrus increases the inclusive fitness of the simulating female, either by increasing the access of related females to suitable males, or by encouraging appropriate oestrus behaviours from female relatives who are not responding correctly to males. Although the observed data do not fully conform to the predictions of any of these hypotheses, we rule out the first two, and tentatively suggest that parous females most likely exhibit false oestrus behaviours in order to demonstrate to naïve relatives at whom to direct their behaviour.

Why do African elephants (Loxodonta africana simulate oestrus? An analysis of longitudinal data.

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Lucy A Bates

Full Text Available Female African elephants signal oestrus via chemicals in their urine, but they also exhibit characteristic changes to their posture, gait and behaviour when sexually receptive. Free-ranging females visually signal receptivity by holding their heads and tails high, walking with an exaggerated gait, and displaying increased tactile behaviour towards males. Parous females occasionally exhibit these visual signals at times when they are thought not to be cycling and without attracting interest from musth males. Using demographic and behavioural records spanning a continuous 28-year period, we investigated the occurrence of this "simulated" oestrus behaviour. We show that parous females in the Amboseli elephant population do simulate receptive oestrus behaviours, and this false oestrus occurs disproportionately in the presence of naïve female kin who are observed coming into oestrus for the first time. We compare several alternative hypotheses for the occurrence of this simulation: 1 false oestrus has no functional purpose (e.g., it merely results from abnormal hormonal changes; 2 false oestrus increases the reproductive success of the simulating female, by inducing sexual receptivity; and 3 false oestrus increases the inclusive fitness of the simulating female, either by increasing the access of related females to suitable males, or by encouraging appropriate oestrus behaviours from female relatives who are not responding correctly to males. Although the observed data do not fully conform to the predictions of any of these hypotheses, we rule out the first two, and tentatively suggest that parous females most likely exhibit false oestrus behaviours in order to demonstrate to naïve relatives at whom to direct their behaviour.

Effects of GnRH vaccination in wild and captive African Elephant bulls (Loxodonta africana on reproductive organs and semen quality.

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Imke Lueders

Full Text Available Although the African elephant (Loxodonta africana is classified as endangered by the International Union for Conservation of Nature (IUCN, in some isolated habitats in southern Africa, contraception is of major interest due to local overpopulation. GnRH vaccination has been promoted as a non-invasive contraceptive measure for population management of overabundant wildlife. We tested the efficacy of this treatment for fertility control in elephant bulls.In total, 17 male African elephants that were treated with a GnRH vaccine were examined in two groups. In the prospective study group 1 (n = 11 bulls, ages: 8-36 years, semen quality, the testes, seminal vesicles, ampullae and prostate, which were all measured by means of transrectal ultrasound, and faecal androgen metabolite concentrations were monitored over a three-year period. Each bull in the prospective study received 5 ml of Improvac® (1000 μg GnRH conjugate intramuscularly after the first examination, followed by a booster six weeks later and thereafter every 5-7 months. In a retrospective study group (group 2, n = 6, ages: 19-33 years, one examination was performed on bulls which had been treated with GnRH vaccine for 5-11 years.In all bulls of group 1, testicular and accessory sex gland sizes decreased significantly after the third vaccination. In six males examined prior to vaccination and again after more than five vaccinations, the testis size was reduced by 57.5%. Mean testicular height and length decreased from 13.3 ± 2.6 cm x 15.2 ± 2.8 cm at the beginning to 7.6 ± 2.1 cm x 10.2 ± 1.8 cm at the end of the study. Post pubertal bulls (>9 years, n = 6 examined prior to vaccination produced ejaculates with viable spermatozoa (volume: 8-175 ml, sperm concentration: 410-4000x106/ml, total motility: 0-90%, while after 5-8 injections, only 50% of these bulls produced ejaculates with a small number of immotile spermatozoa. The ejaculates of group 2 bulls (vaccinated >8 times were

Loxodonta africana (Blumenbach)

African Journals Online (AJOL)

lose-content of the diet of ruminants and non-ruminants. The elephant, like the equidae, exists on a diet with a high cellulose content, and the length of the intestinal canal from the stomach to the ..... Studies on the evolution of the ophryoscolecidae. (Ciliata:Oligotricha) III. Phylogeny of the Ophryoscolecidae based on.

Using camera traps and digital video to investigate the impact of Aethina tumida pest on honey bee (Apis mellifera adansonii reproduction and ability to keep away elephants (Loxodonta africana cyclotis in Gamba, Gabon

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Steeve Ngama

2018-06-01

Full Text Available Bees and elephant interactions are the core of a conservation curiosity since it has been demonstrated that bees, one of the smallest domesticated animals, can keep away elephants, the largest terrestrial animals. Yet, insects' parasites can impact the fitness and activity of the bees. Since their activity is critical to the repellent ability against elephants, this study assessed the impact of small hive beetles (Aethina tumida on bee (Apis mellifera adansonii reproduction and ability to keep forest elephants (Loxodonta africana cyclotis away. Because interspecies interactions are not easy to investigate, we have used camera traps and digital video to observe the activity of bees and their interactions with wild forest elephants under varying conditions of hive infestation with the small hive beetle, a common bee pest. Our results show that queen cells are good visual indicators of colony efficiency on keeping away forest elephants. We give evidences that small hive beetles are equivalently present in large and small bee colonies. Yet, results show no worries about the use of bees as elephant deterrents because of parasitism due to small hive beetles. Apis mellifera adansonii bees seem to effectively cope with small hive beetles showing no significant influence on its reproduction and ability to keep elephants away. This study also reports for the first time the presence of Aethina tumida as a constant beekeeping pest that needs to be addressed in Gabon.

Prosopis Africana SEEDS (OKPEYE)

African Journals Online (AJOL)

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Keywords: Prosopis africana, okpeye seeds, thermal heat conductivity, specific heat capacity, thermal heat diffusivity, .... 2.3 Determination of Thermal Properties of Prosopis. Africana .... and the guard ring was filled with fiber glass at both the.

The Days and Nights of Zoo Elephants: Using Epidemiology to Better Understand Stereotypic Behavior of African Elephants (Loxodonta africana and Asian Elephants (Elephas maximus in North American Zoos.

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Brian J Greco

Full Text Available Stereotypic behavior is an important indicator of compromised welfare. Zoo elephants are documented to perform stereotypic behavior, but the factors that contribute to performance have not been systematically assessed. We collected behavioral data on 89 elephants (47 African [Loxodonta africana], 42 Asian [Elephas maximus] at 39 North American zoos during the summer and winter. Elephants were videoed for a median of 12 daytime hours per season. A subset of 32 elephants (19 African, 13 Asian was also observed live for a median of 10.5 nighttime hours. Percentages of visible behavior scans were calculated from five minute instantaneous samples. Stereotypic behavior was the second most commonly performed behavior (after feeding, making up 15.5% of observations during the daytime and 24.8% at nighttime. Negative binomial regression models fitted with generalized estimating equations were used to determine which social, housing, management, life history, and demographic variables were associated with daytime and nighttime stereotypic behavior rates. Species was a significant risk factor in both models, with Asian elephants at greater risk (daytime: p<0.001, Risk Ratio = 4.087; nighttime: p<0.001, Risk Ratio = 8.015. For both species, spending time housed separately (p<0.001, Risk Ratio = 1.009, and having experienced inter-zoo transfers (p<0.001, Risk Ratio = 1.175, increased the risk of performing higher rates of stereotypy during the day, while spending more time with juvenile elephants (p<0.001, Risk Ratio = 0.985, and engaging with zoo staff reduced this risk (p = 0.018, Risk Ratio = 0.988. At night, spending more time in environments with both indoor and outdoor areas (p = 0.013, Risk Ratio = 0.987 and in larger social groups (p = 0.039, Risk Ratio = 0.752 corresponded with reduced risk of performing higher rates of stereotypy, while having experienced inter-zoo transfers (p = 0.033, Risk Ratio = 1.115 increased this risk. Overall, our results

Seed Dispersal Potential of Asian Elephants

DEFF Research Database (Denmark)

Harich, Franziska K.; Treydte, Anna Christina; Ogutu, Joseph Ochieng

2016-01-01

Elephants, the largest terrestrial mega-herbivores, play an important ecological role in maintaining forest ecosystem diversity. While several plant species strongly rely on African elephants (Loxodonta africana; L. cyclotis) as seed dispersers, little is known about the dispersal potential of As...

Comparing direct image and wavelet transform-based approaches to analysing remote sensing imagery for predicting wildlife distribution

NARCIS (Netherlands)

Murwira, A.; Skidmore, A.K.

2010-01-01

In this study we tested the ability to predict the probability of elephant (Loxodonta africana) presence in an agricultural landscape of Zimbabwe based on three methods of measuring the spatial heterogeneity in vegetation cover, where vegetation cover was measured using the Landsat Thematic Mapper

78 FR 9725 - Endangered Species; Receipt of Applications for Permit

Science.gov (United States)

2013-02-11

...-66682A The applicant requests a permit to re-export a captive-born male Asian elephant (Elephas maximus... species (Mescocapromys species), African elephant (Loxodonta Africana), Asian elephant (Elephas maximus... covers activities to be conducted by the applicant over a 5-year period Applicant: Hawthorn Corporation...

Managing African Elephant Populations: Act or let die

NARCIS (Netherlands)

Colenbrander, Ben; Gooijer, Jean de; Paling, Robert; Stout, Susanna; Stout, Tom; Allen, Twink

2004-01-01

During the last century, the number of African elephant (Loxodonta africana) declined dramatically as a result of over-hunting, poaching for ivory and, more recently, the loss of habitat area due to encroachment of the human population. In some areas, however, the trend to declining numbers was

Antioxidative, anti-inflammatory potentials and phytochemical profile of Commiphora africana (A. Rich. Engl. (Burseraceae and Loeseneriella africana (Willd. (Celastraceae stem leaves extracts

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Moussa Compaoré

2016-08-01

Conclusions: The present study may explain the effectiveness of plants in traditional medicine of Burkina Faso, singularly Commiphora africana and Loeseneriella africana. The next investigation was to sub-fractionate the methanol fraction in order to isolate new antioxidant and/or anti-inflammatory compounds.

Physico-chemical and toxicological studies on Afzelia africana seed ...

African Journals Online (AJOL)

USER

2010-03-29

Mar 29, 2010 ... Table 2. Physico-chemical characteristics of Afzelia africana seed oil*. Property .... The moisture level of the seeds of A. africana is low resulting in low acid .... Keay RWJ, Onochie CFA, Stanfield DP (1964). Nigerian Trees, 2.

Fermentation of Agave tequilana juice by Kloeckera africana: influence of amino-acid supplementations.

Science.gov (United States)

Valle-Rodríguez, Juan Octavio; Hernández-Cortés, Guillermo; Córdova, Jesús; Estarrón-Espinosa, Mirna; Díaz-Montaño, Dulce María

2012-02-01

This study aimed to improve the fermentation efficiency of Kloeckera africana K1, in tequila fermentations. We investigated organic and inorganic nitrogen source requirements in continuous K. africana fermentations fed with Agave tequilana juice. The addition of a mixture of 20 amino-acids greatly improved the fermentation efficiency of this yeast, increasing the consumption of reducing sugars and production of ethanol, compared with fermentations supplemented with ammonium sulfate. The preference of K. africana for each of the 20 amino-acids was further determined in batch fermentations and we found that asparagine supplementation increased K. africana biomass production, reducing sugar consumption and ethanol production (by 30, 36.7 and 45%, respectively) over fermentations supplemented with ammonium sulfate. Therefore, asparagine appears to overcome K. africana nutritional limitation in Agave juice. Surprisingly, K. africana produced a high concentration of ethanol. This contrasts to poor ethanol productivities reported for other non-Saccharomyces yeasts indicating a relatively high ethanol tolerance for the K. africana K1 strain. Kloeckera spp. strains are known to synthesize a wide variety of volatile compounds and we have shown that amino-acid supplements influenced the synthesis by K. africana of important metabolites involved in the bouquet of tequila. The findings of this study have revealed important nutritional limitations of non-Saccharomyces yeasts fermenting Agave tequilana juice, and have highlighted the potential of K. africana in tequila production processes.

Africana-womanism and the sexist paradox in Emeka Nwabueze's ...

African Journals Online (AJOL)

Nwabueze's The Dragon's Funeral, which examines the remote factors that triggered the Aba women's riot, sounds Africana-womanist largely because it adopts a moderate approach in reviewing the relationship between men and women in a male dominated society. Africana-womanism, isolates the black peculiarity of the ...

Why do elephants flap their ears? | Wright | African Zoology

African Journals Online (AJOL)

The blood flow in the ear of the African elephant Loxodonta africana was measured In anaesthetized animals using the dye dilution technique at the same time as the arterio-venous temperature difference. The calculated heat loss from the ear is shown to be a substantial proportion of the total metabolic heat-loss ...

Antioxidative, anti-inflammatory potentials and phytochemical profile of Commiphora africana(A. Rich.) Engl.(Burseraceae) and Loeseneriella africana(Willd.)(Celastraceae) stem leaves extracts

Institute of Scientific and Technical Information of China (English)

Moussa Compaoré; Roland Ng-Tiéro Meda; Sahabi Bakasso; Laurian Vlase; Martin Kiendrebeogo

2016-01-01

Objective: To assess the antioxidant and anti-inflammatory activities as well as to determine the flavonoids and phenolic acids content of active fractions.Methods: Two medicinal plant samples were extracted successively in Soxhlet apparatus with n-hexane, dichloromethane, acetonitrile, ethyl acetate, methanol and n-butanol. Five methods were used to evaluate the antioxidant activity. Anti-inflammatory activity was done through the inhibition of the cyclooxygenase enzymes(COX-1 and COX-2).Polyphenolic compounds were analyzed by using a spectrophotometrical and high performance liquid chromatography-mass spectrometry(HPLC-MS) methods.Results: The data showed that the stem leaves extracts of Commiphora africana and Loeseneriella africana possessed significant in vitro antioxidant and anti-inflammatory activities. Polar extracts had radical scavenging effects and they reduced iron(III). The prostaglandin production was significantly stopped by acetonitrile and methanol extracts.These biological activities were supported by some bioactive compounds quantified by using the HPLC-MS. p-Coumaric acid, ferulic acid, isoquercitrin, quercitrin, quercetin,rutin, kaempferol and apigenin were the most metabolites quantified.Conclusions: The present study may explain the effectiveness of plants in traditional medicine of Burkina Faso, singularly Commiphora africana and Loeseneriella africana.The next investigation was to sub-fractionate the methanol fraction in order to isolate new antioxidant and/or anti-inflammatory compounds.

78 FR 50083 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

Science.gov (United States)

2013-08-16

... a 5-year period. Applicant: Zoological Society of San Diego, San Diego, CA; PRT-08827B The applicant requests a permit to re-import a live female African elephant (Loxodonta africana) born in the wild for the... conducted by the applicant over a 5-year period. Applicant: Pinto Ranch, Hunt, TX; PRT-13263B The applicant...

Power, policy and the Prunus africana bark trade, 1972-2015.

Science.gov (United States)

Cunningham, A; Anoncho, V F; Sunderland, T

2016-02-03

After almost 50 years of international trade in wild harvested medicinal bark from Africa and Madagascar, the example of Prunus africana holds several lessons for both policy and practice in the fields of forestry, conservation and rural development. Due to recent CITES restrictions on P. africana exports from Burundi, Kenya and Madagascar, coupled with the lifting of the 2007 European Union (EU) ban in 2011, Cameroon's share of the global P. africana bark trade has risen from an average of 38% between 1995 and 2004, to 72.6% (658.6 metric tons) in 2012. Cameroon is therefore at the center of this international policy arena. This paper draws upon several approaches, combining knowledge in working with P. africana over a 30-year period with a thorough literature review and updated trade data with "ground-truthing" in the field in 2013 and 2014. This enabled the construction of a good perspective on trade volumes (1991-2012), bark prices (and value-chain data) and the gaps between research reports and practice. Two approaches provided excellent lenses for a deeper understanding of policy failure and the "knowing-doing gap" in the P. africana case. A similar approach to Médard's (1992) analyses of power, politics and African development was taken and secondly, studies of commodity chains that assess the power relations that coalesce around different commodities (Ribot, 1998; Ribot and Peluso, 2003). Despite the need to conserve genetically and chemically diverse P. africana, wild populations are vulnerable, even in several "protected areas" in Burundi, Cameroon, the Democratic Republic of Congo and in the forest reserves of Madagascar. Secondly, hopes of decentralized governance of this forest product are misplaced due to elite capture, market monopolies and subsidized management regimes. At the current European price, for P. africana bark (US$6 per kg) for example, the 2012 bark quota (658.675t) from Cameroon alone was worth over US$3.9 million, with the majority of

pacificus (Caridea) and Upogebia africana

African Journals Online (AJOL)

aemon pacificus and Upogebia africana in and out of .... bottom plankton samples were obtained using two 57-cm WP2 ... KAHLSICO model 005-W A 130 flowmeter. ..... Figure 7 Catch per unit effort of Pa/aemon paci/icus zoea 6 and adults.

INTEGRAÇÃO AFRICANA: DA ORGANIZAÇÃO DA UNIDADE AFRICANA À UNIÃO AFRICANA

OpenAIRE

Diallo, Alfa Oumar

2015-01-01

Desde Kwamé N´Krumah a unidade da África era um grande desejo. A Organização da Unidade Africana (OUA) servia aos olhares de alguns na pobreza moral e material do continente. Destaca-se, que dentro da OUA, alguns fundadores militavam em favor da instituição dos Estados Unidos da África enquanto que outros pregavam, ao contrário, pela fragmentação dos Estados-Nações sob uma forma organizacional. Os Estados Unidos da África certamente seriam limitados à exploração contínua deste continente, mas...

A note on the presence of the Elephant Louse Haematomyzus elephantis piaget (Mallophaga: Rhynchophthirina in the Kruger National Park

Directory of Open Access Journals (Sweden)

L.E.O Braack

1984-12-01

Full Text Available First described in 1869, this rather unusual insect has been found to be a common ectoparasite on the Indian elephant (Elephas maximus, and has been collected in low numbers from the African elephant (Loxodonta africana in nearly all of sub-saharan Africa (Ledger 1979, The arthropod parasites of vertebrates in Africa south of the Sahara (Ethiopian Region Vol. IV.

Cytotoxic glucosphingolipid from Celtis Africana.

Science.gov (United States)

Perveen, Shagufta; Al-Taweel, Areej Mohammad; Fawzy, Ghada Ahmed; El-Shafae, Azza Muhammed; Khan, Afsar; Proksch, Peter

2015-05-01

Literature survey proved the use of the powdered sun-dried bark and roots of Celtis africana for the treatment of cancer in South Africa. The aim of this study was to do further isolation work on the ethyl acetate fraction and to investigate the cytotoxic activities of the various fractions and isolated compound. Cytotoxicity of petroleum ether, chloroform, ethyl acetate, n-butanol fractions and compound 1 were tested on mouse lymphoma cell line L5178Y using the microculture tetrazolium assay. One new glucosphingolipid 1 was isolated from the aerial parts of C. africana. The structure of the new compound was determined by extensive analysis by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry. The ethyl acetate fraction and compound 1 showed strong cytotoxic activity with an EC50 value of 8.3 μg/mL and 7.8 μg/mL, respectively, compared with Kahalalide F positive control (6.3 μg/mL). This is the first report of the occurrence of a cytotoxic glucosphingolipid in family Ulmaceae.

Surgical treatment of an umbilical hernia in a free-ranging sub-adult African elephant in Samburu National Reserve, Kenya

OpenAIRE

Kaitho, Titus; Mijele,Dominic; Njoroge,Michael

2015-01-01

Domnic Mijele, Michael Njoroge, Titus Kaitho Veterinary Services Department, Species Conservation and Management Division, Kenya Wildlife Service, Nairobi, Kenya Abstract: A 10-year-old male African elephant (Loxodonta africana) at Samburu National Reserve in Northern Kenya, weighing approximately 1,600 kg, presented with an umbilical hernia in October 2013. Umbilical herniorrhaphy was carried out under field conditions. Anesthesia was induced and maintained using etorphine hydrochloride for...

Imagens e palavras: suas correspondências na arte africana

OpenAIRE

Maria Corina Rocha

2007-01-01

Esta dissertação constitui-se da pesquisa e do estudo bibliográfico sobre cultura material e arte africana tradicional, aqui entendida como a arte de origem anterior ao período da colonização européia, antes do século XIX, mas também a produzida durante este período, especificamente a arte da África central. Nossa pesquisa reflete o fato de haver no Brasil uma omissão considerável de fontes bibliográficas e de informações específicas sobre arte e cultura material africana em língua portuguesa...

Intestinal protozoa of the African elephant Loxodonta africana ...

African Journals Online (AJOL)

The digestive tract of 15 elephants from South Africa and two from Zaïre were sampled in order to determine the identity, density and population composition of the intestinal protozoa. The following orders were represented: Gymnostomatida, Trichostomatida and Entodiniomorphida. Altogether 17 species were identified, ...

Use of wood anatomy to identify poisonous plants: Charcoal of Spirostachys africana

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Sandra J. Lennox

2015-03-01

Full Text Available Spirostachys africana Sond. (tamboti/tambotie is a woodland tree that is often found near water. It has a poisonous and purgative latex. The archaeological site of Sibudu, a rock shelter in KwaZulu-Natal, has evidence, from well-preserved charcoal and seeds, of past environments and wood use from approximately 77–38 thousand years ago (ka. As their uses and environmental indicators are different, it is critical to confidently distinguish among the three anatomically similar woods of the Euphorbiaceae: Spirostachys africana, Sclerocroton integerrimus and Shirakiopsis elliptica. A detailed anatomical study of reference and archaeological charcoal shows that xylem vessel width increases proportionally as vessel frequency decreases, from Spirostachys africana, Sclerocroton integerrimus to Shirakiopsis elliptica. Crystals of calcium oxalate are present in ray cells of Spirostachys africana, whereas silica bodies are present in ray cells of Sclerocroton integerrimus and Shirakiopsis elliptica. Using these features, the presence of Spirostachys africana was confirmed amongst hearth charcoal of the Spotty Camel layer, with an age of approximately 58 ka and of the Mottled Deposit occupational layer, with an age of approximately 49 ka. The presence of this charcoal, collected from ancient fireplaces or sieved from surrounding sediments, implies that people at Sibudu understood and used this poisonous tree to their advantage. We are encouraged in this view by the presence of many Cryptocarya woodii leaves found on the surface of 77-ka sedge bedding at Sibudu (Wadley L et al., Science. 2011;334:1388–1391. Cryptocarya woodii has insecticidal and larvacidal properties and members of the Laurel family are well known for their medicinal properties.

Age group estimation in free-ranging African elephants based on acoustic cues of low-frequency rumbles

OpenAIRE

Stoeger, Angela S.; Zeppelzauer, Matthias; Baotic, Anton

2014-01-01

Animal vocal signals are increasingly used to monitor wildlife populations and to obtain estimates of species occurrence and abundance. In the future, acoustic monitoring should function not only to detect animals, but also to extract detailed information about populations by discriminating sexes, age groups, social or kin groups, and potentially individuals. Here we show that it is possible to estimate age groups of African elephants (Loxodonta africana) based on acoustic parameters extracte...

ConsciÃncia Corporal e Ancestralidade Africana: Conceitos SociopoÃticos Produzidos por Pessoas de Santo

OpenAIRE

Norval Batista Cruz

2009-01-01

Este estudo apresenta os conceitos sociopoÃticos produzidos por uma comunidade de terreiro de candomblÃ, Ilà Axà Omo TifÃ, localizada no bairro de Jangurussu, na periferia de Fortaleza-Ce. O tema gerador da pesquisa à consciÃncia corporal e ancestralidade africana. Noto que, apesar dos terreiros de candomblÃ, em principio estarem mais conectados com a cultura de matriz africana, nem sempre se encontra uma prÃtica de consciÃncia corporal associada à ancestralidade africana e Ãs vezes, hà uma d...

Effect of supplementation of African breadfruit (Treculia africana ...

African Journals Online (AJOL)

African breadfruit (Treculia africana) hulls were supplemented at different levels with other organic food processing wastes (orange, plantain, cassava and soybean). Optimum supplementation of 40:60 (breadfruit hulls to each waste) was obtained. Proximate and mineral composition of the unsupplemented and the ...

SPATIAL VARIABILITY IN THE MUDPRAWN UPOGEBIA AFRICANA ...

African Journals Online (AJOL)

A nested sampling design was used to examine the variability in density, biomass, sex ratio and size of the estuarine mudprawn Upogebia africana in six estuaries on the south-east coast of South Africa. The objectives were to test the general hypothesis that there is variability in these variables at the scales of regions, ...

Afzelia africana , A Novel Non Starch Polysaccharide, Raised ...

African Journals Online (AJOL)

The effects o vegetable flour prepared from indigenous plant Afzelia africana, a legume, on the fasting plasma cholesterol and triglyceride levels of rats were investigated. Chemical analysis indicated that Afzelia flour contained significant amount of non-starch polysaccharides (NSP). The flour of Afzelia was incorporated ...

in-vitro antimicrobial properties of aspilla africana (compositae).

African Journals Online (AJOL)

Dr Olaleye

The in vitro anti-microbial activity of the petroleum ether, chloroform and methanol extracts of Aspilia africana. (Compositae) was studied. The bacterial used for the antimicrobial analysis consisted of 3 clinical strains of. Staphylococcus aureus, Bacillus subtilis, 2 clinical strains of Escherichia coli and Pseudomonas ...

Determinants of elephant distribution at Nazinga Game Ranch, Burkina Faso

Science.gov (United States)

Jenks, Jonathan A.; Klaver, Robert W.; Wicks, Zeno W.

2007-01-01

We used seasonal ground total counts and remote sensing and GIS technology to relate elephant (Loxodonta africana africana) distribution at Nazinga Game Ranch to environmental and anthropogenic factors. Variables used in analyses were normalized difference vegetation index, elevation, stream density, density of poaching and human illegal activities, distance to dams, distance to rivers, distance to roads, and distance to poaching risk. Contrary to our expectation, road traffic did not disturb elephants. Strong negative relationships were documented between elephant abundance and stream density, distance to dams, and poaching density. Density of poaching and other human illegal activities explained 81%, vegetation greenness 6%, and stream density 3% of the variation in elephant density. Elephant distribution represented a survival strategy affected by poaching, food quality and abundance, and water availability. 

Assessment of Toxicity Profile of Lasianthera Africana Leaf ...

African Journals Online (AJOL)

ALICE

2015-04-15

Apr 15, 2015 ... intraperitoneal, intravenous or intramuscular routes of .... Effect of oral administration of doses of Lasianthera africana leaf extract on body weight of normal rat ... drinking water and treated with metformin (anti-diabetic drug) at a dose level ... glucometer (One Touch Ultra 2 Blood Glucose Monitoring System,.

In-vitro antimicrobial properties of Aspilla africana (compositae ...

African Journals Online (AJOL)

... more active than the soxhlet extracts. Only the cold petroleum ether extract showed a good activity against both C. albicans and A. flavus. The phytochemical screening for the whole plat of A. africana revealed the presence of alkaloids, saponin glycosides and tannins but absence of steroidal nucleus and anthraquinone.

Socio-economic contribution of African breadfruit ( Treculia africana ...

African Journals Online (AJOL)

The Non-Timber Forest Products (NTFPs) the conserve are gathered for household consumption and commercial uses; they have formed an inherent part of rural ... the level of income generation, processing, distribution of sales as well as the importance of Treculia africana to food security in Southeastern, Nigeria in 2015.

Clinical and Parasitological Effects of Aspilia africana (Pers.)

African Journals Online (AJOL)

Department of Pharmacy, Makerere University

extract possessed in vitro antiplasmodial activity (IC50 30µg/ml) but no remarkable cytotoxicity. The A. africana preparation shows potential ... procedure employed by the traditional healers. For this purpose 5-10 tablespoonfuls of .... alkaloids, tannins and traces of essential oils. 1 - cpm in treated in untreated cultures x 100 ...

Allelochemicals Effect of Aqueous Leachate from Oudneya Africana R

African Journals Online (AJOL)

nesrine

2014-03-05

Mar 5, 2014 ... This present study was conducted to investigate the possible allelopathic effect of Oudneya africana. (donor species) on Bromus tectorum (weed species) and Triticum aestivum (cv. Sahel1; crop species) through germination bioassay experiment. B. tectorum is a winter annual grass that grows in winter.

Analgesic and anti-inflammatory effects of the methanol stem bark extract of Prosopis africana.

Science.gov (United States)

Ayanwuyi, Lydia O; Yaro, Abdullahi H; Abodunde, Olajumoke M

2010-03-01

Prosopis africana (Guill. & Perr.) Taub. (Mimosoideae) is a shrub used for menstrual and general body pain in Nupe land in north central Nigeria. In this study, the methanol extract of the stem bark of Prosopis africana (at doses of 62.5, 125, and 250 mg/kg) was evaluated for analgesic and anti-inflammatory activities using acetic acid-induced writhing assay and carrageenan-induced inflammation in rats. The extract significantly (P acetic acid-induced writhing with the highest activity observed at the highest dose, 250 mg/kg (76.89%) comparable to that of piroxicam (83.16%) the standard agent used. In the carrageenan-induced inflammation assay, the extract showed significant anti-inflammatory activity (P screening revealed the presence of flavonoids, saponins, carbohydrates, cardiac glycosides, tannins, and alkaloids. The oral median lethal dose was found to be 3807.9 mg/kg in mice and > 5000 mg/kg in rats. This study supports the folkloric claim of the use of Prosopis africana in the management of pain.

Allelotoxicity of Oudneya africana R. Br. aqueous leachate on ...

African Journals Online (AJOL)

This present study was conducted to investigate the possible allelopathic effect of Oudneya africana (donor species) on Bromus tectorum (weed species) and Triticum aestivum (cv. Sahel1; crop species) through germination bioassay experiment. B. tectorum is a winter annual grass that grows in winter wheat and other ...

The Africana world

DEFF Research Database (Denmark)

It is 127 years since the Scramble for Africa divided up the continent, imposing borders that have led to conflict rather than peace and stability. It is 100 years since the African National Congress (ANC) was founded as the first African liberation movement with pan-African roots. It is nearly 50...... engagements with Africa's rich cultural heritage, its lingering contemporary challenges, its multifaceted systems of knowledge and its future in the exciting context of the twenty-first century. Africana World: From Fragmentation to Unity and Renaissance is put together in order to help develop the study...... and knowledge of African liberation across the continent and the diaspora. This first volume launches a new book series, following the Scramble for Africa conferences held every May to commemorate the founding of the OAU, which will be published annually to support the scholarly study of African unity...

Antimicrobial, Antioxidant, and Wound Healing Properties of Kigelia africana (Lam. Beneth. and Strophanthus hispidus DC.

Directory of Open Access Journals (Sweden)

Christian Agyare

2013-01-01

Full Text Available Microbial infections of various types of wounds are a challenge to the treatment of wounds and wound healing. The study was to investigate antimicrobial and antioxidant properties of methanol leaf and stem bark extracts of Kigelia africana and methanol leaf and root extracts of Strophanthus hispidus and also to determine wound healing properties of the extracts. The antimicrobial activities of the methanol extracts were determined against two Gram-positive and two Gram-negative bacteria and a fungus using agar diffusion and micro-dilution methods. The antioxidant activity was determined using 1,1-diphenyl-2-picryl–hydrazyl (DPPH method. The influence of the extracts on rate of wound closure was investigated using the excision wound model and histopathological investigation of treated and untreated wound tissues performed. The MICs of leaf extract of K. africana against test organisms were 2.5–7.5 mg/mL and stem bark extract were 2.25–7.5 mg/mL. The leaf extract of S. hispidus had MIC range of 2.5–7.5 mg/mL and 2.5–10 mg/mL for root extract. The IC50 of leaf and stem bark extracts of K. africana were 56.9 and 13.7 μg/mL, respectively and leaf and root of S. hispidus were 49.8 and 45.1 μg/mL, respectively. K. africana extracts (7.5% w/w showed significant ( wound contraction at day 7 with 72% of wound closure whiles significant ( wound contractions were observed on day 11 for stem bark of K. africana, leaf and root extracts of S. hispidus. Wound tissues treated with the extracts showed improved collagenation, re-epitheliazition and rapid granulation formation compared with untreated wound tissues. The extracts were found to contain alkaloids, saponins, tannins, flavonoids, carbohydrates, and sapogenetic glycosides. The HPLC finger-printing of the extracts were developed. The leaf, stem bark and root extracts of K. africana and S. hispidus exhibited antimicrobial, antioxidant, and enhanced wound healing properties and these

Antidiarrheal activity of methanolic extract of the root bark of Cordia africana.

Science.gov (United States)

Asrie, Assefa Belay; Abdelwuhab, Mohammedbrhan; Shewamene, Zewdneh; Gelayee, Desalegn Asmelashe; Adinew, Getnet Mequanint; Birru, Eshetie Melese

2016-01-01

An ethnobotanical study in Agew-Awi and Amhara peoples in northwest Ethiopia reported that Cordia africana is used traditionally in the treatment of liver disease, amebiasis, stomachache, and diarrhea. The root and root bark are reported to be used in the treatment of diarrhea. Therefore, this study was intended to evaluate the antidiarrheal effect of C. africana against castor oil-induced diarrhea in mice. The antidiarrheal effect of the plant was tested on castor oil-induced diarrhea in mice (23-25 g) of either sex. Number of diarrheic defecations, intestinal length traveled by the charcoal meal, and weight of intestinal fluid were taken as important parameters to evaluate the antidiarrheal activity of the plant extract. In preliminary phytochemical screening tests, the methanolic extract of C. africana was found to contain phenols, flavonoids, terpenoids, and saponins. Reduction in the number of diarrheic drops was observed in groups of mice that received 200 mg/kg ( P <0.05) and 400 mg/kg ( P <0.01) of the extract compared to the negative controls. The percent inhibition of intestinal fluid accumulation was 26.83%, 46.34%, and 53.66% at the doses of 100, 200, and 400 mg/kg of the extract, respectively. Relative to the negative control group, the mean percent of intestinal length moved by the charcoal meal was decreased by 24.41%, 39.89%, and 51.66% in groups of mice given 100, 200, and 400 mg/kg of the plant extract, respectively. To iterate the finding, the root bark extract of C. africana was found to be effective in preventing castor oil-induced diarrhea and intestinal motility in a dose-dependent manner. This reveals that the plant material has promising antidiarrheal activity as it is claimed in traditional medical practice.

New Sulphated Flavonoids from Tamarix africana and Biological Activities of Its Polar Extract.

Science.gov (United States)

Karker, Manel; De Tommasi, Nunziatina; Smaoui, Abderrazak; Abdelly, Chedly; Ksouri, Riadh; Braca, Alessandra

2016-10-01

The phytochemical investigation of Tamarix africana Poir. (Tamaricaceae) shoot polar extract afforded three new sulphated flavonoids, (2 S ,4 R )-5,7,4'-trihydroxyflavan-4-ol 5,7-disulphate ( 1 ), (2 S )-5,7,4'-trihydroxyflavan 7- O -sulphate ( 2 ), and (2 S )-naringenin 4'- O -sulphate ( 3 ), together with ten known compounds. Their structures were determined by spectroscopic methods including 1D and 2D NMR analysis and HRMS. Biological activities of the polar extract of T. africana shoots related to its phenolic content were also investigated. A high total phenolic content (151.1 mg GAE/g) was found in the methanol shoot extract, which exhibits strong antioxidant activities using the oxygen radical absorbance capacity method and a skin cell-based assay. Moreover, the shoot extract showed significant anti-inflammatory activity, reducing nitric oxide release by 53.5 % at 160 µg/mL in lipopolysaccharide-stimulated RAW 264.7 macrophages. Finally, T. africana shoot extract inhibited the growth of A-549 lung carcinoma cells, with an IC 50 value of 34 µg/mL. Georg Thieme Verlag KG Stuttgart · New York.

El conflicto de Darfur: un reto para la credibilidad de la Unión Africana

Directory of Open Access Journals (Sweden)

María Ángeles Alaminos

2008-01-01

Full Text Available En el caso de la crisis de Darfur la Unión Africana esperaba conseguir su primer éxito a nivel internacional en la pacificación de un conflicto africano; el conflicto de Darfur ha supuesto un reto para su credibilidad. La Misión de la Unión Africana en Sudán (AMIS intentó poner fin a la crisis, pero los recursos limitados, tanto económicos como humanos fueron incapaces de frenarla. La protección de tres millones y medio de personas en situación de riesgo en Darfur ha constituido un desafío para la UA y una prueba de la efectividad de su misión AMIS. La Unión Africana quiere demostrar su valía como organización, su potencial en el desarrollo de acciones concretas, su preponderancia como actor en el ámbito africano y su relevancia como actor internacional.

empirical study of the characteristics of afzelia africana seed under

African Journals Online (AJOL)

HP

significant probably because of the thick seed coat. True density did not show a consistent variation with change in moisture content. 3.2 Mechanical Properties. The mechanical properties study was conducted using the data obtained from the compressive loading of the. Afzelia Africana seeds in a monsan to tensiometer.

Kinetics of saponification of Treculia africana oil using a locally ...

African Journals Online (AJOL)

The investigation on the saponification of Treculia africana (breadfruit) oil using a locally obtained alkaline (Ngu) extracted from the burnt female inflorescence of oil palm bunch using kinetic approach proved successful and showed a high probability of producing good quality toilet soap. The result obtained revealed that ...

Improvement of growth, fermentative efficiency and ethanol tolerance of Kloeckera africana during the fermentation of Agave tequilana juice by addition of yeast extract.

Science.gov (United States)

Díaz-Montaño, Dulce M; Favela-Torres, Ernesto; Córdova, Jesus

2010-01-30

The aim of this work was to improve the productivity and yield of tequila fermentation and to propose the use of a recently isolated non-Saccharomyces yeast in order to obtain a greater diversity of flavour and aroma of the beverage. For that, the effects of the addition of different nitrogen (N) sources to Agave tequilana juice on the growth, fermentative capacity and ethanol tolerance of Kloeckera africana and Saccharomyces cerevisiae were studied and compared. Kloeckera africana K1 and S. cerevisiae S1 were cultured in A. tequilana juice supplemented with ammonium sulfate, diammonium phosphate or yeast extract. Kloeckera africana did not assimilate inorganic N sources, while S. cerevisiae utilised any N source. Yeast extract stimulated the growth, fermentative capacity and alcohol tolerance of K. africana, giving kinetic parameter values similar to those calculated for S. cerevisiae. This study revealed the importance of supplementing A. tequilana juice with a convenient N source to achieve fast and complete conversion of sugars in ethanol, particularly in the case of K. africana. This yeast exhibited similar growth and fermentative capacity to S. cerevisiae. The utilisation of K. africana in the tequila industry is promising because of its variety of synthesised aromatic compounds, which would enrich the attributes of this beverage. (c) 2009 Society of Chemical Industry.

Biodiesel from the seed oil of Treculia africana with high free fatty acid content

Energy Technology Data Exchange (ETDEWEB)

Adewuyi, Adewale [Redeemer' s University, Department of Chemical Sciences, Faculty of Natural Sciences, Redemption City, Ogun State (Nigeria); Oderinde, Rotimi A.; Ojo, David F.K. [University of Ibadan, Industrial Unit, Department of Chemistry, Ibadan, Oyo State (Nigeria)

2012-12-15

Oil was extracted from the seed of Treculia africana using hexane. The oil was characterized and used in the production of biodiesel. Biodiesel was produced from the seed oil of T. africana using a two-step reaction system. The first step was a pretreatment which involved the use of 2 % sulfuric acid in methanol, and secondly, transesterification reaction using KOH as catalyst. Saponification value of the oil was 201.70 {+-} 0.20 mg KOH/g, free fatty acid was 8.20 {+-} 0.50 %, while iodine value was 118.20 {+-} 0.50 g iodine/100 g. The most dominant fatty acid was C18:2 (44 %). The result of the method applied showed a conversion which has ester content above 98 %, flash point of 131 {+-} 1.30 C, and phosphorus content below 1 ppm in the biodiesel. The biodiesel produced exhibited properties that were in agreement with the European standard (EN 14214). This study showed that the high free fatty acid content of T. africana seed oil can be reduced in a one-step pretreatment of esterification reaction using H{sub 2}SO{sub 4} as catalyst. (orig.)

Patch-occupancy survey of elephant (Loxodonta africana surrounding Livingstone, Zambia

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David A. Youldon

2017-01-01

Full Text Available Wild elephants represent the biggest human–wildlife conflict issue in Livingstone, Zambia. However, little is known about their movements. This survey investigated elephants’ habitat use outside a core protected and fenced zone that forms part of Mosi-oa-Tunya National Park, Zambia. Using ‘patch-occupancy’ methodology, indications of elephant presence (feeding behaviour, dung and tracks were surveyed. The survey aimed to assist proposed future monitoring exercises by defining the geographical extent that should be considered to improve accuracy in species abundance estimates. Results were supplemented using collected indications of elephant presence from prior monitoring exercises, and during this survey. Elephant presence was confirmed up to 8 km from the boundary of the protected core habitat, focussed in: (1 an unfenced zone of the national park, (2 along a road leading from the national park to the Dambwa Forest to the north and (3 along two rivers located to the west (Sinde River and east (Maramba River of the core area. Detection probability of elephant presence was high using these methods, and we recommend regular sampling to determine changes in habitat use by elephants, as humans continue to modify land-use patterns. Conservation implications: Identification of elephant ranging behaviour up to 8 km outside of the Mosi-oa-Tunya National Park in southern Zambia will assist in managing human– elephant conflict in the area, as well as in assessing this seasonal population’s abundance.

Morphological aspects and composition of African elephant (Loxodonta africana ivory

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E.J. Raubenheimer

1999-07-01

Full Text Available This study was aimed at determining the origin of the diamond shaped pattern and composition of ivory of the African elephant. Fragments of ivory and tusks were obtained through the National Parks Board from the Kruger Park, Addo Elephant Park, Kaokoveld, Caprivi, Etosha, Kavango and Tembe Elephant Park. Polished surfaces were prepared in different planes and examined with light and electron microscopical techniques. Analyses of the inorganic composition were performed using atomic absorption spectrophotometry, ion selective electrodes and inductively coupled optical emission spectroscopy. The total amino acid composition was determined with the aid of an amino acid analyser. Morphological investigations showed the distinctive diamond shaped pattern of ivory to be caused by the sinusoidal surface to pulpal course followed by odontoblastic tubules. This course is the result of pressure which builds up between tightly packed odontoblasts on their centripetal course along an ever decreasing pulpal circumference during formation of ivory. A total of 17 elements were detected in the inorganic fraction of ivory, some in concentrations as low as 0.25 ^g/g. The concentrations of calcium, magnesium, fluoride, cobalt and zinc showed statistically significant differences (P < 0.007 between selected regions and may prove valuable in distinguishing chemically between ivory from different geographical locations. The organic content of ivory showed 17 amino acids in varying concentrations. The possible causes of these variations are discussed.

Uncommon mandibular osteomyelitis in a cat caused by Nocardia africana.

Science.gov (United States)

de Farias, Marconi Rodrigues; Werner, Juliana; Ribeiro, Márcio Garcia; Rodigheri, Sabrina Marin; Cavalcante, Carolina Zaghi; Chi, Kung Darh; Condas, Larissa Anuska Zeni; Gonoi, Tohru; Matsuzama, Tetsuhiro; Yazama, Katsukiyo

2012-12-06

Nocardiosis is an unusual infection in companion animals characterized by suppurative to pyogranulomatous lesions, localized or disseminated. Cutaneous-subcutaneous, pulmonary and systemic signs are observed in feline nocardiosis. However, osteomyelitis is a rare clinical manifestation in cats. Nocardia cyriacigeorgica (formerly N. asteroides sensu stricto), Nocardia brasiliensis, Nocardia otitidiscaviarum, and Nocardia nova are the most common pathogenic species identified in cats, based on recent molecular classification (16S rRNA gene). The present report is, to our knowledge, the first case of mandibular osteomyelitis in a cat caused by Nocardia africana, diagnosed based upon a combination of methods, including molecular techniques. A one-year-old non-neutered female cat, raised in a rural area, was admitted to the Companion Animal Hospital-PUCPR, São José dos Pinhais, State of Paraná, Brazil, with a history a progressive facial lesion, difficulty apprehending food, loss of appetite, apathy and emaciation. Clinical examination showed fever, submandibular lymphadenitis, and a painless, 8 cm diameter mass, which was irregularly-shaped, of firm consistency, and located in the region of the left mandible. The skin around the lesion was friable, with diffuse inflammation (cellulitis), multiple draining sinuses, and exudation of serosanguinous material containing whitish "sulfur" granules.Diagnosis was based initially in clinical signs, microbiological culture, cytological, and histopathological findings, and radiographic images. Molecular sequencing of 16S rRNA of isolate allowed diagnosis of Nocardia africana. Despite supportive care and antimicrobial therapy based on in vitro susceptibility testing the animal died. The present report describes a rare clinical case of feline osteomyelitis caused by Nocardia africana, diagnosed based upon a combination of clinical signs, microbiological culture, cytological and histopathological findings, radiographic images, and

In Vivo Hypoglycemic Effect of Kigelia africana (Lam): Studies With Alloxan-Induced Diabetic Mice.

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Njogu, Stephen M; Arika, Wycliffe M; Machocho, Alex K; Ngeranwa, Joseph J N; Njagi, Eliud N M

2018-01-01

The claims by the traditional herbal medicine practitioners that Kigelia africana has bioactivity against several diseases, including diabetes mellitus, were investigated in this study. Type I diabetes mellitus was induced in mice by intraperitoneal administration of alloxan monohydrate followed by treatment with the therapeutic doses of the aqueous and ethyl acetate leaf extract of K africana to the experimentally diabetic mice. The treatment effects were compared with the normal control, diabetic control, and diabetic control rats treated with a standard antidiabetic drugs (insulin administered intraperitoneally at 1 IU/kg body weight in 0.1 mL physiological saline or glibenclamide administered orally at 3 mg/kg body weight in 0.1 mL physiological saline). Phytochemical composition of the leaf extract was assessed using standard procedures and mineral elements assessed using atomic absorption spectrophotometry and total reflection X-ray fluorescence system. Oral and intraperitoneal administration of the aqueous and ethyl acetate leaf extract caused a statistically significant dose-independent reduction in plasma glucose level in alloxan-induced diabetic mice. The observed hypoglycemic activity of this plant extract could be attributed to the observed phytochemicals and trace elements, which have been associated with exhibiting antidiabetic properties. Therefore, the data appear to support the hypoglycemic effects of K africana validating its folkloric usage.

Complete mitochondrial genome and phylogeny of Pleistocene mammoth Mammuthus primigenius.

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Evgeny I Rogaev

2006-03-01

Full Text Available Phylogenetic relationships between the extinct woolly mammoth (Mammuthus primigenius, and the Asian (Elephas maximus and African savanna (Loxodonta africana elephants remain unresolved. Here, we report the sequence of the complete mitochondrial genome (16,842 base pairs of a woolly mammoth extracted from permafrost-preserved remains from the Pleistocene epoch--the oldest mitochondrial genome sequence determined to date. We demonstrate that well-preserved mitochondrial genome fragments, as long as approximately 1,600-1700 base pairs, can be retrieved from pre-Holocene remains of an extinct species. Phylogenetic reconstruction of the Elephantinae clade suggests that M. primigenius and E. maximus are sister species that diverged soon after their common ancestor split from the L. africana lineage. Low nucleotide diversity found between independently determined mitochondrial genomic sequences of woolly mammoths separated geographically and in time suggests that north-eastern Siberia was occupied by a relatively homogeneous population of M. primigenius throughout the late Pleistocene.

Una valoración de la geografía y la diáspora africana

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Judith A. Carney

2006-01-01

Full Text Available El estudio de la diáspora Africana se ha vuelto un area vibrante de investigación y enseñanza en los años recientes a través de las disciplinas. Sin embargo, hay muy pocas contribuciones geográficas. Este artículo busca invertir esta tendencia. Se revisa el trabajo relevante de geógrafos en el Atlántico Negro para identificar temas prometedores para la investigación futura. La dispersión de plantas Africanas y el papel de los esclavos en establecer estas plantas es especialmente prometedor. Esta dirección de investigación clarifica los componentes Africanos de Intercambio Colombino mientras llama la atención sobre la importancia de la subsistencia en el negocio transatlántico de esclavos y la economía de las plantaciones. Las comidas básicas de origen Africano sirvieron a la subsistencia y a la memoria. Plantas Africanas figuran de manera prominente en los caminos de la comida en la diáspora, las practicas litúrgicas de las religiones Afro-sincréticas, y en las historias orales de Maroon.

Effect of Methanol extract of Kigelia africana on Sperm Motility and ...

African Journals Online (AJOL)

The fertility activities of the fruit of Kigelia africana Lam. Benth. Family Bignoniaceae, a medicinal plant used in south eastern Nigeria by local traditional healers for treatment of fertility abnormalities especially in male and female adults has been carried out. The research revealed that male rats treated with the methanol ...

Age profiles in elephant and mammoth bone assemblages

Science.gov (United States)

Haynes, Gary

1985-11-01

Age profiles of modern African elephant ( Loxodonta africana) populations are significantly affected by drought conditions that cause local die-offs. Subadult animals die in proportions that may be nearly twice what is recorded in live populations. Such biasing of death sample age profiles might also have occurred during late Pleistocene die-offs of Mammuthus. This comparative study of modern and fossil proboscidean age structures supports a tentative interpretation that late Pleistocene extinction of Mammuthus (at least in the southwestern United States) resulted from severe drought conditions, at which Clovis hunters were witnesses, but not necessarily frequent participants.

Differentiation in a geographical mosaic of plants coevolving with ants: phylogeny of the Leonardoxa africana complex (Fabaceae: Caesalpinioideae) using amplified fragment length polymorphism markers.

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Brouat, C; McKey, D; Douzery, E J P

2004-05-01

Comprising four allopatric subspecies that exhibit various grades of ant-plant interactions, from diffuse to obligate and symbiotic associations, the Leonardoxa africana complex (Fabaceae, Caesalpinioideae) provides a good opportunity to investigate the evolutionary history of ant-plant mutualisms. A previous study of the L. africana complex based on chloroplast DNA noncoding sequences revealed a lack of congruence between clades suggested by morphological and plastid characters. In this study, we analysed phylogenetic relationships within the L. africana complex using a Bayesian probability approach on amplified fragment length polymorphism markers. The results reported permit partial validation of the four subspecies of L. africana previously defined by morphological and ecological markers. Incongruences between phylogenies based on chloroplast DNA and amplified fragment length polymorphism markers are discussed in the light of morphological and ecological data, and confronted with hypotheses of convergence, lineage sorting and introgression.

Use patterns, use values and management of Afzelia africana Sm. in Burkina Faso: implications for species domestication and sustainable conservation.

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Balima, Larba Hubert; Nacoulma, Blandine Marie Ivette; Ekué, Marius Rodrigue Mensah; Kouamé, François N'Guessan; Thiombiano, Adjima

2018-03-27

The lack of literature on the interactions between indigenous people and the valuable agroforestry trees hinder the promotion of sustainable management of plant resources in West African Sahel. This study aimed at assessing local uses and management of Afzelia africana Sm. in Burkina Faso, as a prerequisite to address issues of domestication and sustainable conservation. One thousand forty-four peoples of seven dominant ethnic groups were questioned in 11 villages through 221 semi-structured focus group interviews. The surveys encompassed several rural communities living around six protected areas along the species distribution range. Questions refer mainly to vernacular names of A. africana, locals' motivations to conserve the species, the uses, management practices and local ecological knowledge on the species. Citation frequency was calculated for each response item of each questionnaire section to obtain quantitative data. The quantitative data were then submitted to comparison tests and multivariate statistics in R program. A. africana is a locally well-known tree described as a refuge of invisible spirits. Due to this mystery and its multipurpose uses, A. africana is conserved within the agroforestry systems. The species is widely and mostly used as fodder (87.55%), drugs (75.93%), fetish or sanctuary (70.95%), food (41.49%), and raw material for carpentry (36.19%) and construction (7.05%). While the uses as fodder, food and construction involved one organ, the leaves and wood respectively, the medicinal use was the most diversified. All tree organs were traditionally used in 10 medical prescriptions to cure about 20 diseases. The species use values differed between ethnic groups with lower values within the Dagara and Fulani. The findings reveal a total absence of specific management practices such as assisted natural regeneration, seeding, or transplantation of A. africana sapling. However, trees were permanently pruned and debarked by local people

Uncommon mandibular osteomyelitis in a cat caused by Nocardia africana

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de Farias Marconi

2012-12-01

Full Text Available Abstract Background Nocardiosis is an unusual infection in companion animals characterized by suppurative to pyogranulomatous lesions, localized or disseminated. Cutaneous-subcutaneous, pulmonary and systemic signs are observed in feline nocardiosis. However, osteomyelitis is a rare clinical manifestation in cats. Nocardia cyriacigeorgica (formerly N. asteroides sensu stricto, Nocardia brasiliensis, Nocardia otitidiscaviarum, and Nocardia nova are the most common pathogenic species identified in cats, based on recent molecular classification (16S rRNA gene. The present report is, to our knowledge, the first case of mandibular osteomyelitis in a cat caused by Nocardia africana, diagnosed based upon a combination of methods, including molecular techniques. Case presentation A one-year-old non-neutered female cat, raised in a rural area, was admitted to the Companion Animal Hospital-PUCPR, São José dos Pinhais, State of Paraná, Brazil, with a history a progressive facial lesion, difficulty apprehending food, loss of appetite, apathy and emaciation. Clinical examination showed fever, submandibular lymphadenitis, and a painless, 8 cm diameter mass, which was irregularly-shaped, of firm consistency, and located in the region of the left mandible. The skin around the lesion was friable, with diffuse inflammation (cellulitis, multiple draining sinuses, and exudation of serosanguinous material containing whitish “sulfur” granules. Diagnosis was based initially in clinical signs, microbiological culture, cytological, and histopathological findings, and radiographic images. Molecular sequencing of 16S rRNA of isolate allowed diagnosis of Nocardia africana. Despite supportive care and antimicrobial therapy based on in vitro susceptibility testing the animal died. Conclusion The present report describes a rare clinical case of feline osteomyelitis caused by Nocardia africana, diagnosed based upon a combination of clinical signs, microbiological

Evaluation of the effects of Olea europaea L. subsp. africana (Mill.) P.S. Green (Oleaceae) leaf methanol extract against castor oil-induced diarrhoea in mice.

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Amabeoku, George J; Bamuamba, Kapinga

2010-03-01

Olea europaea L. subsp. africana (Mill.) P.S. Green is widely used in South Africa by traditional medicine practitioners to treat diarrhoea. However, little is known scientifically about this South African species in the treatment of diarrhoea. The main aim of the study therefore was to investigate the antidiarrhoeal effect of the leaf methanol extract of the plant species in mice. The antidiarrhoeal activity of the leaf methanol extract of O. europaea subsp. africana was studied using a castor oil-induced diarrhoeal test. The antipropulsive activity of the plant extract was also investigated using the charcoal meal transit test. Standard methods were used to investigate the acute toxicity and effect of O. europaea subsp. africana on castor oil-induced intraluminal fluid accumulation. Leaf methanol extract of O. europaea subsp. africana and loperamide, a standard antidiarrhoeal drug, significantly reduced the number of diarrhoeal episodes induced by castor oil, significantly decreased the stool mass, significantly delayed the onset of the diarrhoea and protected the animals against castor oil-induced diarrhoea. Both O. europaea subsp. africana and loperamide significantly decreased the gastrointestinal transit of charcoal meal and castor oil-induced intraluminal fluid accumulation in mice. The LD50 value was found to be 3475 mg/kg (p.o.). The results obtained suggest that the leaf methanol extract of O. europaea subsp. africana has an antidiarrhoeal property and that, given orally, it may be non-toxic and/or safe in mice.

Ovulation, pregnancy, placentation and husbandry in the African elephant (Loxodonta africana)

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Allen, W.R

2006-01-01

The African elephant reproduces so efficiently in the wild that overpopulation is now a serious problem in some game parks in Zimbabwe, Botswana and South Africa. The female reaches puberty between 10 and 12 years of age in the wild and, when in captivity, shows oestrous cycles of 14–15 weeks duration. She readily conceives a singleton in the wild yet her uterus has the capacity for twins. She shows a gestation length of 22 months and, in the wild, shows a population density and feed dependent intercalving interval of 4–8 years. The trophoblast erodes the lumenal epithelium of the endometrium and stimulates upgrowths of blood vessel-containing stromal villi, which develop eventually into the broad, tightly folded lamellae of the zonary, endotheliochorial placenta. Significant quantities of leaked maternal erythrocytes and ferric iron are phagocytosed by specialized trophoblast cells in the haemophagous zones at the lateral edges of the placental band. Although the placenta itself is endocrinologically inert, the foetal gonads, which enlarge greatly during the second half of pregnancy can synthesize 5α-dihydryoprogesterone and other 5α pregnane derivatives from cholesterol and pregnenolone. These products may synergize with progestagens secreted by the 2–8 large corpora lutea which are always present in the maternal ovaries throughout gestation to maintain the pregnancy state. PMID:16627297

Ovulation, pregnancy, placentation and husbandry in the African elephant (Loxodonta africana)

OpenAIRE

Allen, W.R

2006-01-01

The African elephant reproduces so efficiently in the wild that overpopulation is now a serious problem in some game parks in Zimbabwe, Botswana and South Africa. The female reaches puberty between 10 and 12 years of age in the wild and, when in captivity, shows oestrous cycles of 14–15 weeks duration. She readily conceives a singleton in the wild yet her uterus has the capacity for twins. She shows a gestation length of 22 months and, in the wild, shows a population density and feed dependen...

Gc-ms, hplc profiling, antioxidant, antimicrobial and cytotoxicity studies of malcolmia africana leaves

International Nuclear Information System (INIS)

Bokhari, T.H.; Rasool, N.; Riaz, M.; Riaz, M.

2014-01-01

Plants are known to be the richest source of natural antioxidant and antimicrobial properties. The use of herbs and medicinal plants as the first medicines is a universal phenomenon. The present study was carried out to examine the antioxidant, antimicrobial and cytotoxicity potential Malcolmia africana leaves extract, fraction, essential oil and fixed oil. The whole plant was extracted with absolute methanol and further fractionated with increasing polarity based absolute solvents. Different fractions were taken by solvent extraction method and their antimicrobial activities were determined. The IC50 and % inhibition by linoleic acid oxidation was evaluated for the antioxidant studies. The cytotoxicity of the plant extract and fractions were assayed against human blood erythrocytes (RBCs). The DPPH scavenging and linoleic acid oxidation assays were carried out. Qualitative and quantitative analysis of secondary metabolites was also carried out. The presence of phenolics was also studied by HPLC. The GC-MS analysis of Malcolmia africana essential oil and fixed oil was also carried out. (author)

Comparative study of the chemical composition and mineral element content of Artocarpus heterophyllus and Treculia africana seeds and seed oils.

Science.gov (United States)

Ajayi, Ibironke Adetolu

2008-07-01

A comparative study of Artocarpus heterophyllus and Treculia africana seeds, both of Moraceae family, was carried out to establish their chemical compositions and evaluate their mineral element content in order to investigate the possibility of using them for human and or animal consumption and also to examine if there is a relationship between the properties of these seeds. A. heterophyllus and T. africana are rich in protein; their protein contents are higher than those from high protein animal sources such as beef and marine fishes. Both seeds have high carbohydrate content and could act as source of energy for animals if included in their diets. The oil contents of the seeds are 11.39% and 18.54% for A. heterophyllus and T. africana, respectively. The oils are consistently liquid at room temperature. The results of the physicochemical properties of the two seeds are comparable to those of conventional oil seeds such as groundnut and palm kernel oils and could be useful for nutritional and industrial purposes. The seeds were found to be good sources of mineral elements. The result revealed potassium to be the prevalent mineral elements which are 2470.00 ppm and 1680.00 ppm for A. heterophyllus and T. africana, respectively followed by sodium, magnesium and then calcium. They also contain reasonable quantity of iron, in particular A. heterophyllus 148.50 ppm.

ANALGESIC ACTIVITY OF PET ETHER, AQUEOUS, AND HYDRO-ETHANOLIC LEAF EXTRACTS OF ASPILIA AFRICANA (PERS) C.D. ADAMS (ASTERACEAE) IN RODENTS

OpenAIRE

Koffuor George Asumeng; Ameyaw Elvis Ofori; Oppong Kyekyeku James; Amponsah Kingsley Isaac; Sunkwa Andrews; Semenyo Samuella Afriyie

2013-01-01

Traditionally, Aspilia africana is used in the management of pain in Ghana and most parts of West Africa. This study therefore investigated the analgesic effect of the petroleum ether, aqueous, and hydro-ethanolic leaf extracts of Aspilia africana using rodent models. Preliminary phytochemical screening was done on all the extracts, which showed the presence of alkaloids, flavonoids, saponins, tannins, glycosides, phytosterols and terpenoids. The extracts (40-400 mg/kg p.o.) were administered...

Comparative study of physicochemical analysis of prosopis africana seeds fermented with different starter cultures

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G. P. Oyeyiola

2017-01-01

Full Text Available Prosopis africana (African mesquite is one of the lesser known legume seed crops in Nigeria, which in a fermented state, gives a food condiment. Because of its rich protein content (about 34%, efforts are made to utilize some lesser known legumes to improve the nutritional status of the people. This study was carried out by fermenting Prosopis africana seeds with mono and mixed cultures of bacterial isolates to produce a local condiment called Okpehe. Standard AOAC methods were used to determine the pH, total sugar and crude protein content of the fermented seeds. During the production of Okpehe with mono cultures of bacteria, the pH ranged between 6.80 and 8.92; total sugar between 10.2 and 7.5 mg/g, and crude protein between 34.62 and 41.25%. In the mixed culture inoculated samples, the pH increased from 7.00 to 8.92; total sugar decreased from 9.4 to 7.4 mg/g, while the crude protein increased (35.02 - 44.61% significantly (p < 0.05 as the fermentation progressed. The highest crude protein content of 44.61% was obtained with the combination of Bacillus subtilis and Bacillus licheniformis, while the lowest protein content referred to the combination of Bacillus megaterium and Bacillus pumilus. The result of this study showed that Prosopis africana seeds could be utilized for the production of Okpehe using mixed cultures of B. subtilis and B. licheniformis, so as to increase the protein intake of the populace.

A Review of the Potential of Phytochemicals from Prunus africana (Hook f. Kalkman Stem Bark for Chemoprevention and Chemotherapy of Prostate Cancer

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Richard Komakech

2017-01-01

Full Text Available Prostate cancer remains one of the major causes of death worldwide. In view of the limited treatment options for patients with prostate cancer, preventive and treatment approaches based on natural compounds can play an integral role in tackling this disease. Recent evidence supports the beneficial effects of plant-derived phytochemicals as chemopreventive and chemotherapeutic agents for various cancers, including prostate cancer. Prunus africana has been used for generations in African traditional medicine to treat prostate cancer. This review examined the potential roles of the phytochemicals from P. africana, an endangered, sub-Saharan Africa plant in the chemoprevention and chemotherapy of prostate cancer. In vitro and in vivo studies have provided strong pharmacological evidence for antiprostate cancer activities of P. africana-derived phytochemicals. Through synergistic interactions between different effective phytochemicals, P. africana extracts have been shown to exhibit very strong antiandrogenic and antiangiogenic activities and have the ability to kill tumor cells via apoptotic pathways, prevent the proliferation of prostate cancer cells, and alter the signaling pathways required for the maintenance of prostate cancer cells. However, further preclinical and clinical studies ought to be done to advance and eventually use these promising phytochemicals for the prevention and chemotherapy of human prostate cancer.

Potentials of leaves of Aspilia africana (Compositae in wound care: an experimental evaluation

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Akah PA

2007-07-01

Full Text Available Abstract Background The potentials of the leaves of the haemorrhage plant, Aspilia africana C. D Adams (Compositae in wound care was evaluated using experimental models. A. africana, which is widespread in Africa, is used in traditional medicine to stop bleeding from wounds, clean the surfaces of sores, in the treatment of rheumatic pains, bee and scorpion stings and for removal of opacities and foreign bodies from the eyes. The present study was undertaken to evaluate the potentials for use of leaves of this plant in wound care. Methods The effect of the methanol extract (ME and the hexane (HF and methanol (MF fractions (obtained by cold maceration and graded solvent extraction respectively on bleeding/clotting time of fresh experimentally-induced wounds in rats, coagulation time of whole rat blood, growth of microbial wound contaminants and rate of healing of experimentally-induced wounds in rats were studied as well as the acute toxicity and lethality (LD50 of the methanol extract and phytochemical analysis of the extract and fractions. Results The extract and fractions significantly (P ME>HF. Also, the extract and fractions caused varying degrees of inhibition of the growth of clinical isolates of Pseudomonas fluorescens and Staphylococcus aureus, as well as typed strains of Ps. aeruginosa (ATCC 10145 and Staph. aureus (ATCC 12600, and reduced epithelialisation period of wounds experimentally-induced in rats. Acute toxicity and lethality (LD50 test in mice established an i.p LD50 of 894 mg/kg for the methanol extract (ME. Phytochemical analysis revealed the presence of alkaloids, saponins, tannins, flavonoids, resins, sterols, terpenoids and carbohydrates. Conclusion The leaves of A. africana possess constituents capable of arresting wound bleeding, inhibiting the growth of microbial wound contaminants and accelerating wound healing which suggest good potentials for use in wound care.

Antidiarrheal activity of methanolic extract of the root bark of Cordia africana

OpenAIRE

Asrie, Assefa Belay; Abdelwuhab, Mohammedbrhan; Shewamene, Zewdneh; Gelayee, Desalegn Asmelashe; Adinew, Getnet Mequanint; Birru, Eshetie Melese

2016-01-01

Assefa Belay Asrie, Mohammedbrhan Abdelwuhab, Zewdneh Shewamene, Desalegn Asmelashe Gelayee, Getnet Mequanint Adinew, Eshetie Melese Birru Department of Pharmacology, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia Abstract: An ethnobotanical study in Agew-Awi and Amhara peoples in northwest Ethiopia reported that Cordia africana is used traditionally in the treatment of liver disease, amebiasis, stomachache...

Liberation Through Education: Teaching #BlackLivesMatter in Africana Studies

OpenAIRE

Danielle M. Wallace

2016-01-01

This paper is based on teaching about #BlackLivesMatter in Africana Studies in two seminar courses during the Spring of 2015 and 2016, respectively. Guided by a pedagogy grounded in the belief that education can be a tool of social justice, arguments are made for how to frame discussions of #BlackLivesMatter in regard to the socio-historical circumstances that inform and shape the modern day movement. In addition, suggestions are made for including a discussion of the tradition of activism wi...

Vegetative Propagation Trial of Prosopis africana (Guill. et Perr.) Taub. by Air Layering under Sudano-Sahelian Climate in the South-Central Niger

OpenAIRE

Abdou, Laouali; Karim, Saley; Habou, Rabiou; Mahamane, Ali

2015-01-01

Prosopis africana is a species of great socioeconomic importance but threatened with extinction in Niger because of overuse and regeneration problem. This study, conducted in the Maradi (Niger) area, precisely at El Gueza in the south of Gazaoua department, aims to evaluate the vegetative propagation capacity of P. africana by air layering under the Sudano-Sahelian climate of the south-central Niger. A ring of bark was taken on each selected branch and the wound was covered with a black plast...

Prunus africana (Hook.f.) Kalkman: the overexploitation of a medicinal plant species and its legal context.

Science.gov (United States)

Bodeker, Gerard; van 't Klooster, Charlotte; Weisbord, Emma

2014-11-01

The linkage between herbal medicines and the sustainability of medical plants from which they are manufactured is increasingly being understood and receiving attention through international accords and trade labeling systems. However, little attention is paid to the fair trade aspects of this sector, including the issue of benefit-sharing agreements with traditional societies whose knowledge and resources are being exploited for commercial herbal medicine development and production. This article examines the case of Prunus africana (Hook.f.) Kalkman, from equatorial Africa. While the conservation and cultivation dimension of the trade in P. africana has been much discussed in literature, no research appears to have focused on the traditional resource rights and related ethical dimensions of this trade in traditional medicine of Africa. Serving as a cautionary tale for the unbridled exploitation of medicinal plants, the history of P. africana extraction is considered here in the context of relevant treaties and agreements existing today. These include the Nagoya Protocol, a supplementary agreement to the Convention on Biological Diversity, the Trade-Related Aspects of Intellectual Property Rights agreement from the World Trade Organization, and two African regional frameworks: the Swakopmund Protocol and the Organisation Africaine de la Propriété Intellectuelle Initiative. In the context of strengthening medicinal plant research in Africa, a novel international capacity-building project on traditional medicines for better public health in Africa will be discussed, illustrating how access and benefit sharing principles might be incorporated in future projects on traditional medicines.

Antibacterial, antifungal and antioxidant activity of Olea africana against pathogenic yeast and nosocomial pathogens.

Science.gov (United States)

Masoko, Peter; Makgapeetja, David M

2015-11-17

Olea africana leaves are used by Bapedi people to treat different ailments. The use of these leaves is not validated, therefore the aim of this study is to validate antimicrobial properties of this plant. The ground leaves were extracted using solvents of varying polarity (hexane, chloroform, dichloromethane (DCM), ethyl acetate, acetone, ethanol, methanol, butanol and water). Thin layer chromatography (TLC) was used to analyse the chemical constituents of the extracts. The TLC plates were developed in three different solvent systems, namely, benzene/ethanol/ammonium solution (BEA), chloroform/ethyl acetate/formic acid (CEF) and ethyl acetate/methanol/water (EMW). The micro-dilution assay and bioautography method were used to evaluate the antibacterial activity of the extracts against Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus and the antifungal activity against Candida albicans and Cryptococcus neoformans. Methanol was the best extractant, yielding a larger amount of plant material whereas hexane yielded the least amount. In phytochemical analyses, more compounds were observed in BEA, followed by EMW and CEF. Qualitative 2, 2- diphenylpacryl-1-hydrazyl (DPPH) assay displayed that all the extracts had antioxidant activity. Antioxidant compounds could not be separated using BEA solvent system while with CEF and EMW enabled antioxidant compounds separation. The minimum inhibitory concentrations (MIC) values against test bacteria ranged between 0.16 and 2.50 mg/mL whereas against fungi, MIC ranged from 0.16 to 0.63 mg/mL. Bioautography results demonstrated that more than one compound was responsible for antimicrobial activity in the microdilution assay as the compounds were located at different Rf values. The results indicate that leaf extracts of Olea africana contain compounds with antioxidant, antibacterial and antifungal activities. Therefore, further studies are required to isolate the active compounds and perform

Nuclear microprobe studies of elemental distributions in dormant seeds of Burkea africana

Science.gov (United States)

Witkowski, E. T. F.; Weiersbye-Witkowski, I. M.; Przybyłowicz, W. J.; Mesjasz-Przybyłowicz, J.

1997-07-01

Seed nutrient stores are vital post-germination for the establishment of seedlings in harsh and unpredictable environments. Plants of nutrient-poor environments allocate a substantial proportion of total acquired nutrients to reproduction (i.e. seeds). We propose that differential allocation of mineral resources to specific seed tissues is an indication of a species germination and establishment strategy. Burkea africana Hook is a leguminous tree typical of broad-leaved nutrient-poor savannas in southern Africa. Elemental distributions in dormant B. africana seed structures were obtained using the true elemental imaging system (Dynamic Analysis) of the NAC Van de Graaff nuclear microprobe. Raster scans of 3.0 MeV protons were complemented by simultaneous BS and PIXE point analyses. Mineral nutrient concentrations varied greatly between seed tissues. Elevated levels of metals known to play an important role as plant enzyme co-factors were found in the seed lens and embryonic axis. Distributions of most of these metals (Ca, Mn, Fe and Zn, but not K or Cu) were positively correlated with embryonic P distribution, and probably represent phytin deposits. The distribution of metals within seed structures is 'patchy' due to their complexation with P as electron-dense globoid phytin crystals, which constrains the interpretation of PIXE point analyses.

EVALUATION OF CEMENT-BONDED PARTICLE BOARD PRODUCED FROM AFZELIA AFRICANA WOOD RESIDUES

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OLUFEMI A. SOTANNDE

2012-12-01

Full Text Available The study was design to evaluate the physical and mechanical properties of cement-bonded particleboards produced from Afzelia africana wood residues. The production variables investigated were three wood particle types (flakes, flake-sawdust mix and sawdust, three chemical accelerators (CaCl2, MgCl2 and AlCl3 and four wood-cement ratios (1:2.0, 1:2.5, 1:3.0 and 1:3.5. The accelerators were based on 2% by weight of cement used. The boards produced were subjected to physical tests such as density, percentage water absorption and thickness swelling. Mechanical properties evaluated were modulus of rupture, internal bonding strength and compressive strength. The results revealed that the type of particle used, wood-cement ratio and chemical additives had a marked influence on the physical and mechanical properties of the boards (p < 0.05. From quality view point, flake-sawdust composite ranked best while flake boards ranked least. Similarly, CaCl2 had the best influence on the setting of the boards followed by MgCl2 and AlCl3. Finally, it has been shown that particle boards that satisfied the BISON type HZ requirement and ISO 8335 can be produced from Afzelia africana particularly at wood-cement of 1:2.5 and above.

Basic Density and Strength Properties Variations in Cordia Africana (Lam) Grown Under Agroforestry in Arumeru, Tanzania

NARCIS (Netherlands)

Mahonge, C.P.I.

2007-01-01

Variations in basic density and strength properties of Cordia africana (lam) grown under agroforestry in Arumeru district Arusha Tanzania were determined. Tree sampling procedure and data collection based on standard methods (ISO 3129.of 1975). The main results indicated that basic density increased

Characterization of casein and alpha lactalbumin of African elephant (Loxodonta africana) milk.

Science.gov (United States)

Madende, M; Osthoff, G; Patterton, H-G; Patterton, H E; Martin, P; Opperman, D J

2015-12-01

The current research reports partial characterization of the caseins and α-lactalbumin (α-LA) of the African elephant with proposed unique structure-function properties. Extensive research has been carried out to understand the structure of the casein micelles. Crystallographic structure elucidation of caseins and casein micelles is not possible. Consequently, several models have been developed in an effort to describe the casein micelle, specifically of cow milk. Here we report the characterization of African elephant milk caseins. The κ-caseins and β-caseins were investigated, and their relative ratio was found to be approximately 1:8.5, whereas α-caseins were not detected. The gene sequence of β-casein in the NCBI database was revisited, and a different sequence in the N-terminal region is proposed. Amino acid sequence alignment and hydropathy plots showed that the κ-casein of African elephant milk is similar to that of other mammals, whereas the β-casein is similar to the human protein, and displayed a section of unique AA composition and additional hydrophilic regions compared with bovine caseins. Elephant milk is destabilized by 62% alcohol, and it is speculated that the β-casein characteristics may allow maintenance of the colloidal nature of the casein micelle, a role that was previously only associated with κ-casein. The oligosaccharide content of milk was reported to be low in dairy animals but high in some other species such as humans and elephants. In the milk of the African elephant, lactose and oligosaccharides both occur at high levels. These levels are typically related to the content of α-LA in the mammary gland and thus point to a specialized carbohydrate synthesis, where the whey protein α-LA plays a role. We report the characterization of African elephant α-LA. Homology modeling of the α-LA showed that it is structurally similar to crystal structures of other mammalian species, which in turn may be an indication that its functional properties, such as lactose synthesis, should not be impaired. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Corrosion Inhibition of Aluminium by Treculia Africana Leaves Extract in Acid Medium

OpenAIRE

Ejikeme, P.M.; Umana, S.G.; Onukwuli, O.D.

2012-01-01

The inhibitive effect of Treculia Africana leaves extract (TALE) in the corrosion of aluminium in HCl solution was studied using weight loss and thermometric methods at 30-60 °C. The results showed that TALE acted as a corrosion inhibitor of aluminium in HCl. Inhibition efficiency increased with increase in TALE concentration, but decreased with increase in temperature. TALE interaction with the metal surface was found to obey Freundlich and El-Awady adsorption isotherms. The obtained heats o...

Cinco dificultades para construir la historia de la filosofía africana

OpenAIRE

de Diego González, Antonio

2013-01-01

Desde la teoría postcolonial se han cuestionado los modelos de historia de las ideas impuestos por el africanismo y el orientalismo. Diferentes teóricos africanos –Bachir Diagne, Mundimbe, Wiredu o Kete Asante– han formulado diversas soluciones para superar las dificultades. Este trabajo explora las principales dificultades y las propuestas para elaborar una historia de la filosofía africana. The postcolonial theory was questioning the patterns of History of Ideas imposed by Orientalism an...

As literaturas africanas de língua portuguesa

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Pires Laranjeira

2000-03-01

Full Text Available O autor traça o percurso genérico das literaturas africanas de língua portuguesa, nos últimos ISO a nos, mostrando como os movimentos, revistas e obras se foram pautando, cada vez mais intensamente, pela busca da identidade própria, autonômica, nacional, dentro da língua comum e de heranças culturais diversas. De entre essas heranças, destacam-se o Modernismo, o Neo-rea lismo, a Negritude ou o romance social do Nordeste brasileiro. Mas, fundamentalmente, as literaturasafri canas formaram-se como nacionais, antes da nacionalidade, através de uma retórica e uma imagética que enfa tizavam o concreto, o social, a história e o político.

Proteomic analysis of a pleistocene mammoth femur reveals more than one hundred ancient bone proteins

DEFF Research Database (Denmark)

Cappellini, Enrico; Jensen, Lars Juhl; Szklarczyk, Damian Milosz

2012-01-01

We used high-sensitivity, high-resolution tandem mass spectrometry to shotgun sequence ancient protein remains extracted from a 43 000 year old woolly mammoth (Mammuthus primigenius) bone preserved in the Siberian permafrost. For the first time, 126 unique protein accessions, mostly low-abundance......We used high-sensitivity, high-resolution tandem mass spectrometry to shotgun sequence ancient protein remains extracted from a 43 000 year old woolly mammoth (Mammuthus primigenius) bone preserved in the Siberian permafrost. For the first time, 126 unique protein accessions, mostly low......-abundance extracellular matrix and plasma proteins, were confidently identified by solid molecular evidence. Among the best characterized was the carrier protein serum albumin, presenting two single amino acid substitutions compared to extant African (Loxodonta africana) and Indian (Elephas maximus) elephants. Strong...

Cephaloleia sp. Cerca a Vagelineata Pic*, una Plaga de la Palma Africana

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Urueta Sandino Eduardo

1972-08-01

Full Text Available Cephalolia sp. y Cephaloleila sp, se han empleado como sinónimos del género Cepaloleia sp. (Lepesme. 1947. Se sabe que los estados de larva y adulto atacan el follaje de la palma africana (Elaeis guineensis Jacq. trayendo muchas veces como consecuencia secamientos en los folíolos o su invasión por hongos. En Colombia el Cephaloleia próximo a vagelineata Pic se presenta en la zona de Urabá y posiblemente en el Departamento de Santander.

The effects of smoke derivatives on in vitro seed germination and development of the leopard orchid Ansellia africana

Czech Academy of Sciences Publication Activity Database

Papenfus, H. B.; Naidoo, D.; Pošta, Martin; Finnie, J. F.; van Staden, J.

2016-01-01

Roč. 18, č. 2 (2016), s. 289-294 ISSN 1435-8603 Institutional support: RVO:61388963 Keywords : Ansellia africana * developmental rate index * germination rate index * karrikinolide * leopard orchid * smoke-water * trimethylbutenolide Subject RIV: CC - Organic Chemistry Impact factor: 2.106, year: 2016

How immunocontraception can contribute to elephant management in small, enclosed reserves: Munyawana population as a case study.

Science.gov (United States)

Druce, Heleen C; Mackey, Robin L; Slotow, Rob

2011-01-01

Immunocontraception has been widely used as a management tool to reduce population growth in captive as well as wild populations of various fauna. We model the use of an individual-based rotational immunocontraception plan on a wild elephant, Loxodonta africana, population and quantify the social and reproductive advantages of this method of implementation using adaptive management. The use of immunocontraception on an individual, rotational basis stretches the inter-calving interval for each individual female elephant to a management-determined interval, preventing exposing females to unlimited long-term immunocontraception use (which may have as yet undocumented negative effects). Such rotational immunocontraception can effectively lower population growth rates, age the population, and alter the age structure. Furthermore, such structured intervention can simulate natural process such as predation or episodic catastrophic events (e.g., drought), which regulates calf recruitment within an abnormally structured population. A rotational immunocontraception plan is a feasible and useful elephant population management tool, especially in a small, enclosed conservation area. Such approaches should be considered for other long-lived, social species in enclosed areas where the long-term consequences of consistent contraception may be unknown.

How immunocontraception can contribute to elephant management in small, enclosed reserves: Munyawana population as a case study.

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Heleen C Druce

Full Text Available Immunocontraception has been widely used as a management tool to reduce population growth in captive as well as wild populations of various fauna. We model the use of an individual-based rotational immunocontraception plan on a wild elephant, Loxodonta africana, population and quantify the social and reproductive advantages of this method of implementation using adaptive management. The use of immunocontraception on an individual, rotational basis stretches the inter-calving interval for each individual female elephant to a management-determined interval, preventing exposing females to unlimited long-term immunocontraception use (which may have as yet undocumented negative effects. Such rotational immunocontraception can effectively lower population growth rates, age the population, and alter the age structure. Furthermore, such structured intervention can simulate natural process such as predation or episodic catastrophic events (e.g., drought, which regulates calf recruitment within an abnormally structured population. A rotational immunocontraception plan is a feasible and useful elephant population management tool, especially in a small, enclosed conservation area. Such approaches should be considered for other long-lived, social species in enclosed areas where the long-term consequences of consistent contraception may be unknown.

Development of the tush and tusk and tusklessness in African elephant (Loxodonta africana

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E.J. Raubenheimer

2000-07-01

Full Text Available The embryologic development of the tush and tusk of the African elephant was studied by means of serial histologic sections prepared from elephant embryos with masses varying between Ig and 240 g. Statistics on tusklessness obtained during a four year population control programme in the Kruger National Park were analysed and compared with those reported in other elephant reserves in Southern Africa. Maxillae of eight elephant embryos, the maternal histories of which were available in six cases, were radiographed, dissected and examined microscopically. This study has shown that the tush and tusk develop from one tooth germ in a deciduous to permanent tooth relationship. Tusklessness was found to be unilateral or bilateral and associated with either the absence or presence of a tush. The possible causes of the differences in the frequency of bilateral tusklessness in different elephant populations are discussed.

COMADRE

DEFF Research Database (Denmark)

Salguero-Gómez, Roberto; Jones, Owen; Archer, C. Ruth

2016-01-01

exists for databases on population dynamics spanning the rich diversity of the animal kingdom. This information is fundamental to our understanding of the conditions that have shaped variation in animal life histories and their relationships with the environment. Furthermore, an animal population...... schedules of reproduction and mortality determine its invasive potential, and its risk of local extinction, which are at the core of conservation biology. 2.Matrix population models (MPMs) are among the most widely used demographic tools by animal ecologists. MPMs project population dynamics in terms...... of reproduction, mortality, and development over the entire life cycle. The results of MPMs have direct biological interpretations, facilitating comparisons among animal species as different as Caenorhabditis elegans, Loxodonta africana and Homo sapiens. 3.Thousand of animal demographic records exist in the form...

COMADRE - A global data base of animal demography

DEFF Research Database (Denmark)

Salguero-Gómez, Roberto; Jones, Owen R.; Archer, C. Ruth

2016-01-01

spanning the rich diversity of the animal kingdom world-wide. This information is fundamental to our understanding of the conditions that have shaped variation in animal life histories and their relationships with the environment, as well as the determinants of invasion and extinction. Matrix population...... models (MPMs) are among the most widely used demographic tools by animal ecologists. MPMs project population dynamics based on the reproduction, survival and development of individuals in a population over their life cycle. The outputs from MPMs have direct biological interpretations, facilitating...... comparisons among animal species as different as Caenorhabditis elegans, Loxodonta africana and Homo sapiens. Thousands of animal demographic records exist in the form of MPMs, but they are dispersed throughout the literature, rendering comparative analyses difficult. Here, we introduce the COMADRE Animal...

Phytochemical screening by LC-MS and LC-PDA of ethanolic extracts from the fruits of Kigelia africana (Lam.) Benth.

Science.gov (United States)

Costa, Rosaria; Albergamo, Ambrogina; Pellizzeri, Vito; Dugo, Giacomo

2017-06-01

Kigelia africana is a tree native to Africa, with a local employment in numerous fields, ranging from traditional medicine to cosmetics and religious rituals. Parts of the plant generally used are stem bark, fruits, roots and leaves. The fruits, which have a singular 'sausage' shape, are widely exploited by local folk, in particular for applications/products involving genito-urinary apparatus of both human genders. The scope of this work was to make a consistent chemical investigation on this plant species, in order to clarify and increase the information at present available in literature. To this aim, ethanolic extracts of K. africana fruits were analysed by high-performance liquid chromatography with photodiode array (HPLC-PDA) and electrospray-mass spectrometry (HPLC-ESI-MS) detection, revealing the presence of polyphenols and iridoids. The two detection systems used along with standard co-injection and comparison with previous reports, led to the identification and quantification of six phenolic compounds and three iridoids.

Composición de los subproductos de la industrialización de la Palma Africana utilizados en la alimentación animal en Costa Rica

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Emilio Vargas

2003-01-01

Full Text Available Se determinó la composición nutricional y variabilidad de la harina de coquito de palma africana extraída por solvente (HCPAS, la harina de coquito de palma africana de extracción mecánica (HCPAM, el coquito integral de la palma africana (CIPA, la grasa cruda de la palma africana (GCPA y los ácidos grasos libres de la palma africana (AGLPA. Los resultados indicaron que la HCPAS y la HCPAM producidas en Costa Rica tienen una composición nutricional semejante a la reportada en la literatura internacional, excepto por un mayor contenido de grasa residual, con valores de 3,3 y 13,2% para los productos locales en comparación con 1,75 y 10,94% para los producidos en otros países. Asimismo, se observó una mayor variabilidad en el contenido de fibra y grasa de los productos locales. El CIPA es un material con un alto contenido de grasa (46-49%; 8-9% de proteína cruda y 10- 12% de fibra; lo cual lo convierte en un producto de un alto potencial nutricional. Los valores de energía digestible en cerdos fueron de 3000, 3215 y 4780 Kcal kg-1 de MS para la HCPAS, HCPAM y el CIPA, respectivamente. En aves la energía metabolizable aparente fue de 1399, 1789 y 4230 Kcal kg-1 de MS. La GCPA y los AGLPA mostraron una composición típica de ácidos grasos para estos materiales, con una relación ácidos grasos insaturados y ácidos grasos saturados de 1,01 y 0,78, respectivamente. El contenido de energía digestible de la GCPA en cerdos fue de 8064 Kcal kg-1 de MS y la energía metabolizable aparente en aves fue de 8615 Kcal kg-1 de MS. En los AGLPA, los valores observados fueron de 6859 y 5068 Kcal kg-1 de MS. Se sugiere valores de los niveles por utilizar en la formulación de raciones para diferentes especies de animales de esos subproductos.

Prevalence of Candida albicans, Candida dubliniensis and Candida africana in pregnant women suffering from vulvovaginal candidiasis in Argentina.

Science.gov (United States)

Mucci, María Josefina; Cuestas, María Luján; Landanburu, María Fernanda; Mujica, María Teresa

Vulvovaginal candidiasis (VVC) is a vulvovaginitis commonly diagnosed in gynecology care. In recent years, the taxonomy of the most important pathogenic Candida species, such as Candida albicans have undergone significant changes. This study examined the prevalence of C. albicans, Candida africana, and Candida dubliniensis in vaginal specimens from 210 pregnant women suffering from vulvovaginitis or having asymptomatic colonization. Phenotypic and molecular methods were used for the identification of the species. During the studied period, 55 isolates of Candida or other yeasts were obtained from specimens collected from 52 patients suffering from vulvovaginitis (24.8%). C. albicans was the predominant Candida species in 42 isolates (80.7%), either alone or in combination with other species of the genus (5.7%, n=3). Additionally, nine isolates of C. albicans (50%) were obtained from asymptomatic patients (n=18). C. dubliniensis was the causative agent in 2 (3.8%) cases of VVC, and was also isolated in one asymptomatic patient. Molecular assays were carried out using specific PCR to amplify the ACT1-associated intron sequence of C. dubliniensis. The amplification of the HWP1 gene also correctly identified isolates of the species C. albicans and C. dubliniensis. No C. africana was isolated in this work. Some C. albicans isolates were either homozygous or heterozygous at the HWP1 locus. The distribution of heterozygous and homozygous C. albicans isolates at the HWP1 locus was very similar among patients suffering from VVC and asymptomatic patients (p=0.897). The presence of C. albicans and C. dubliniensis, and the absence of C. africana in pregnant is noteworthy. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

BEHAVIOR OF CÓRDIA AFRICANA (Cordia africana Lam. CULTIVATED IN SOIL CONTAMINATED BY HEAVY METALS AND TREATED WITH AMENDMENT MATERIALS

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Ana Carolina Callegario Pereira

2013-08-01

Full Text Available http://dx.doi.org/10.5902/1980509810544This study aimed to evaluate the remediation of two soils contaminated with heavy metals from soil excavations, located near the port of Itaguaí, through the techniques of chemical immobilization and phytostabilization using the species Cordia africana. The data were collected in the ore courtyard from ‘Companhia Siderúgica Nacional’ (CSN, in the port of Itaguaí, Rio de Janeiro state. In order to reduce the solubility of heavy metals present in these substrates, two industrial waste products produced by CSN were used as ameliorating products, the steelmaking slag and the mill scale, in different concentrations. The plant species was considered with potential to be used in programs of phytostabilization, due to its heavy metal tolerance studied and to high accumulation of such elements in roots and stem. In the substrate of low combination, the lowest accumulation of Zinc and Cadmium in stems and leaves occurred with the use of 4% of soothing. In the substrate of high accumaltion it was 6%.

Mitochondrial DNA analysis of two southern African elephant populations

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M.F. Essop

1996-08-01

Full Text Available The modern view is that there are at most only two valid forms of the African elephant namely Loxodonta qfricana africana, the bush elephant, and L.a. cyclotis, the forest elephant (Ansell 1974; Meester et al. 1986. The Knysna elephant which was also described as a separate sub-species is now almost extinct. Plans to augment the remnant population by introducing other animals must take into account the taxonomic questions and issue of conserving elephant gene pools (Greig 1982a. Mitochondrial DNA (mtDNA restriction fragment-size comparisons were performed on specimens from the Kruger National Park and the Addo Elephant National Park. If the Addo population's results are extrapolated to the Knysna population, it may be concluded that there is no genetic evidence for the Kruger and Knysna elephant populations to be considered as different sub-species.

Spotted hyaenas Crocuta crocuta prey on new-born elephant calves in Hwange National Park, Zimbabwe

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Julia Salnicki

2001-07-01

Full Text Available Spotted hyaena Crocuta crocuta are known to be opportunists and to have a varied diet including mammals, reptiles and birds. Prey most often hunted are medium sized ungulates but spotted hyaenas will on occasion take larger species such as giraffe Giraffa camelopardalis and zebra Equus burchellii. They are also known to hunt whichever species are most abundant and will vary their prey seasonally. In this study spotted hyaenas were observed to take an unusual prey species in the form of elephant calves (Loxodonta africana. On a number of occasions hyaenas were observed feeding on or killing newborn and very young elephant calves. These observations were made whilst the authors were conducting research on spotted hyaena ecology in the woodlands of Hwange National Park, Zimbabwe and were made during the dry season between September and November 1999.

Measuring positive and negative affect in the voiced sounds of African elephants (Loxodonta africana).

Science.gov (United States)

Soltis, Joseph; Blowers, Tracy E; Savage, Anne

2011-02-01

As in other mammals, there is evidence that the African elephant voice reflects affect intensity, but it is less clear if positive and negative affective states are differentially reflected in the voice. An acoustic comparison was made between African elephant "rumble" vocalizations produced in negative social contexts (dominance interactions), neutral social contexts (minimal social activity), and positive social contexts (affiliative interactions) by four adult females housed at Disney's Animal Kingdom®. Rumbles produced in the negative social context exhibited higher and more variable fundamental frequencies (F(0)) and amplitudes, longer durations, increased voice roughness, and higher first formant locations (F1), compared to the neutral social context. Rumbles produced in the positive social context exhibited similar shifts in most variables (F(0 )variation, amplitude, amplitude variation, duration, and F1), but the magnitude of response was generally less than that observed in the negative context. Voice roughness and F(0) observed in the positive social context remained similar to that observed in the neutral context. These results are most consistent with the vocal expression of affect intensity, in which the negative social context elicited higher intensity levels than the positive context, but differential vocal expression of positive and negative affect cannot be ruled out.

Secondary Metabolites from Jacaranda Mimosifolia and Kigelia Africana (Bignoniaceae and Their Anticandidal Activity

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Lazare Sidjui Sidjui

2014-05-01

Full Text Available From the stem barks of Jacaranda mimosifolia benzoic acid (1, 1-naphthaleneacetic acid, 5-carboxy- 1,2,3,4,4a,7,8,8a-octahydro-1,2,4a-trimethyl-[1S-(1α,2β,4aβ,8aα] ( 2, betulinic acid ( 3, lupeol (4 and ursolic acid (5 were isolated. Similarly, lapachol (6, dehydro-α-lapachone (7, 2- acetylfuro-1, 4-naphthoquinone (8, p-coumaric acid (9, caffeic acid (10, nonacosanoic acid, 2-(4-hydroxyphenylethyl ester (11, β-sitosterol (12, kigelinol (13, oleanolic acid (14, β-friedelinol (15, pomolic acid (16, and kojic acid (17 were isolated from the stem barks of Kigelia africana. All the isolated compounds were characterized by using spectroscopic methods especially 1D and 2D NMR and ESI mass spectrometry and comparison with literature data. To the best of our knowledge, compounds 1, 2, 3 and 5, and compounds 11, 14, 15 and 16 were isolated for the first time from Jacaranda mimosifolia and Kigelia africana, respectively. All these compounds were screened for anticandidal activity by agar diffusion method and microbroth dilution technique on four Candida albicans strains (ATCCL26, ATCC12C, ATCCP37039, and ATCCP37037. Among them, compounds 9, 10, and 17 exhibited the highest anticandidal activity that varied between the microbial species (MIC= 0.01 ± 0.00 − 0.03 ± 0.00 mg/mL on C. albicans ATCCL26, ATCCP37037, ATCCP37039 and ATCC12C strains. Compound 17 was likely the most active against the four Candida albicans strains (MIC= 0.01 ± 0.00 − 0.02 ± 0.00 mg/mL.

Studies on the biocidal and cell membrane disruption potentials of stem bark extracts of Afzelia africana (Smith

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DAVID A AKINPELU

2009-01-01

Full Text Available We had recently reported antibacterial activity in the crude extract of the stem bark of Afzelia africana (Akinpelu et al., 2008. In this study, we assessed the biocidal and cell membrane disruption potentials of fractions obtained from the crude extract of the plant. The aqueous (AQ and butanol (BL fractions exhibited appreciable antibacterial activities against the test bacteria. The minimum inhibitory concentrations of the AQ and BL fractions ranged between 0.313 and 2.5 mg/ml, while their minimum bactericidal concentrations varied between 0.625 and 5.0 mg/ml. Also, the AQ fraction killed about 95.8% of E. coli cells within 105 min at a concentration of 5 mg/ml, while about 99.1% of Bacillus pumilus cells were killed by this fraction at the same concentration and exposure time. A similar trend was observed for the BL fraction. At a concentration of 5 mg/ml, the butanol fraction leaked 9.8 μg/ml of proteins from E. coli cells within 3 h, while the aqueous fraction leaked 6.5 μg/ml of proteins from the same organisms at the same concentration and exposure time. We propose that the stem bark of Afzelia africana is a potential source of bioactive compounds of importance to the pharmaceutical industry.

Evaluation of CAMP-Like Effect, Biofilm Formation, and Discrimination of Candida africana from Vaginal Candida albicans Species

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Keyvan Pakshir

2017-01-01

Full Text Available Candida africana as a species recovered from female genital specimens is highly close to C. albicans. The present study was conducted to discriminate C. africana from presumptive vaginal C. albicans strains by molecular assay and evaluate their hemolysin activity, biofilm formation, and cohemolytic effect (CAMP with vaginal bacterial flora. A total of 110 stock vaginal C. albicans isolates were examined by HWP1 gene amplification. Hemolysin activity and the ability of biofilm formation were evaluated by blood plate assay and visual detection methods, respectively. Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus agalactiae were used to evaluate the CAMP-like effects in Sabouraud blood agar media. Based on the size of the amplicons (941 bp, all isolates were identified as C. albicans. All samples were able to produce beta-hemolysin. Moreover, 69 out of 110 of the isolates (62.7% were biofilm-positive, 54 out of 110 Candida isolates (49% demonstrated cohemolytic effects with S. agalactiae, and 48 out of 110 showed this effect with S. aureus (43.6%. All isolates were CAMP-negative with S. epidermidis. We detected all isolates as Candida albicans and almost half of the isolates were CAMP-positive with S. aureus and S. agalactiae, suggesting that these bacteria increase the pathogenicity of Candida in vaginal candidiasis.

Evaluation of CAMP-Like Effect, Biofilm Formation, and Discrimination of Candida africana from Vaginal Candida albicans Species

Science.gov (United States)

Bordbar, Mahboubeh; Nouraei, Hasti; Khodadadi, Hossein

2017-01-01

Candida africana as a species recovered from female genital specimens is highly close to C. albicans. The present study was conducted to discriminate C. africana from presumptive vaginal C. albicans strains by molecular assay and evaluate their hemolysin activity, biofilm formation, and cohemolytic effect (CAMP) with vaginal bacterial flora. A total of 110 stock vaginal C. albicans isolates were examined by HWP1 gene amplification. Hemolysin activity and the ability of biofilm formation were evaluated by blood plate assay and visual detection methods, respectively. Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus agalactiae were used to evaluate the CAMP-like effects in Sabouraud blood agar media. Based on the size of the amplicons (941 bp), all isolates were identified as C. albicans. All samples were able to produce beta-hemolysin. Moreover, 69 out of 110 of the isolates (62.7%) were biofilm-positive, 54 out of 110 Candida isolates (49%) demonstrated cohemolytic effects with S. agalactiae, and 48 out of 110 showed this effect with S. aureus (43.6%). All isolates were CAMP-negative with S. epidermidis. We detected all isolates as Candida albicans and almost half of the isolates were CAMP-positive with S. aureus and S. agalactiae, suggesting that these bacteria increase the pathogenicity of Candida in vaginal candidiasis. PMID:29318048

DE MANDELA À ZUMA: A IMPORTÂNCIA DO ATLÂNTICO SUL NA POLÍTICA EXTERNA SUL-AFRICANA

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Anselmo Otavio

2017-09-01

Full Text Available O artigo busca compreender a importância do Atlântico Sul na política externa sul-africana pós-apartheid. Baseando-se em ampla bibliografia relacionada ao tema, busca-se defender a hipótese de que o aumento do interesse pelo Atlântico Sul em verdade é resultado da valorização por parte da África do Sul das relações Sul-Sul.

Elephants - a conservation overview

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H.S. Riddle

2010-01-01

Full Text Available Loss of habitat is one of the most significant problems facing elephants worldwide, leading to clashes over resources between wildlife and humans where elephants receive the largest part of blame - defined as Human Elephant Conflict (HEC. The sub-Saharan region of Africa contains an approximate population of 500,000 elephants that occupy 37 range countries. The African Elephant (Loxodonta africana is categorized as Vulnerable in the Red List of Threatened Species; they are listed there as two distinct subspecies: the Savanna Elephant (L. a. africana and the Forest Elephant (L. a. cyclotis. The Red List of Threatened Species categorizes the Asian Elephant (Elephas maximus as endangered, and today they are found in 13 range states. The Asian Elephant population is estimated to be 30,000 to 50,000 with approximately 60% of the population being present in India. Due to threats of poaching, the elephant ivory debate has been an important part of recent meetings of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES as Parties have debated proposals for one-time sales of legal government stockpiles of elephant tusks. To maintain elephant populations into the future, long-term and large-scale planning is necessary to ensure adequate space and protection for elephants and people living in elephant habitats.

Complete genome sequence of the halophilic bacterium Spirochaeta africana type strain (Z-7692T) from the alkaline Lake Magadi in the East African Rift

Energy Technology Data Exchange (ETDEWEB)

Liolios, Konstantinos [U.S. Department of Energy, Joint Genome Institute; Abt, Birte [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Scheuner, Carmen [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Teshima, Hazuki [Los Alamos National Laboratory (LANL); Held, Brittany [Los Alamos National Laboratory (LANL); Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Nolan, Matt [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Deshpande, Shweta [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Pagani, Ioanna [U.S. Department of Energy, Joint Genome Institute; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Mavromatis, K [U.S. Department of Energy, Joint Genome Institute; Mikhailova, Natalia [U.S. Department of Energy, Joint Genome Institute; Huntemann, Marcel [U.S. Department of Energy, Joint Genome Institute; Pati, Amrita [U.S. Department of Energy, Joint Genome Institute; Chen, Amy [U.S. Department of Energy, Joint Genome Institute; Palaniappan, Krishna [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Rohde, Manfred [HZI - Helmholtz Centre for Infection Research, Braunschweig, Germany; Tindall, Brian [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Bristow, James [U.S. Department of Energy, Joint Genome Institute; Eisen, Jonathan [U.S. Department of Energy, Joint Genome Institute; Markowitz, Victor [U.S. Department of Energy, Joint Genome Institute; Hugenholtz, Philip [U.S. Department of Energy, Joint Genome Institute; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute

2013-01-01

Spirochaeta africana Zhilina et al. 1996 is an anaerobic, aerotolerant, spiral-shaped bacte- rium that is motile via periplasmic flagella. The type strain of the species, Z-7692T, was iso- lated in 1993 or earlier from a bacterial bloom in the brine under the trona layer in a shallow lagoon of the alkaline equatorial Lake Magadi in Kenya. Here we describe the features of this organism, together with the complete genome sequence, and annotation. Considering the pending reclassification of S. caldaria to the genus Treponema, S. africana is only the second 'true' member of the genus Spirochaeta with a genome-sequenced type strain to be pub- lished. The 3,285,855 bp long genome of strain Z-7692T with its 2,817 protein-coding and 57 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.

Caprellidae (Crustacea: Peracarida: Amphipoda) from the Red Sea and Suez Canal, with the redescription of Metaprotella africana and Paradeutella multispinosa.

Science.gov (United States)

Zeina, Amr F; Guerra-García, José M

2016-04-06

The Caprellidae from the Red Sea are reviewed based on the literature data and new collections from the Hurghada coasts. So far, only six valid species has been reported from the Red Sea and Suez Canal: Caprella equilibra Say, 1818, Hemiaegina minuta Mayer, 1890, Metaprotella africana Mayer, 1903, Paracaprella pusilla Mayer, 1890 and Paradeutella multispinosa Schellenberg, 1928 and Pseudocaprellina pambanensis Sundara Raj, 1927. The type material of M. africana (deposited in the Muséum nacional d'Histoire naturelle, Paris) and Paradeutella multispinosa (deposited in the Museum für Naturkunde, Berlin) are redescribed and illustrated in detail. P. pambanensis and H. minuta were the most abundant species in the collections along the northern coast. Most of the sampling effort has been focused on algae from shallow waters; additional substrates such as sediments, hydroids and coral rubble, especially from areas deeper than 15 meters should be explored. The number of caprellid species in the Red Sea is low compared to adjacent waters, as the Mediterranean Sea. However, further research and more extensive caprellid collections should be conducted along the coasts of Saudi Arabia, Yemen, Sudan and Eritrea, which are still unexplored.

Vegetative Propagation Trial of Prosopis africana (Guill. et Perr. Taub. by Air Layering under Sudano-Sahelian Climate in the South-Central Niger

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Laouali Abdou

2015-01-01

Full Text Available Prosopis africana is a species of great socioeconomic importance but threatened with extinction in Niger because of overuse and regeneration problem. This study, conducted in the Maradi (Niger area, precisely at El Gueza in the south of Gazaoua department, aims to evaluate the vegetative propagation capacity of P. africana by air layering under the Sudano-Sahelian climate of the south-central Niger. A ring of bark was taken on each selected branch and the wound was covered with a black plastic filled with a damp mixture of soil and wood debris. The chosen parameters are the diameter class and the position on the branch. In all, 60 branches were treated and followed for 130 days: 28.33% produced shoots and there was no significant difference between the diameter classes and between the positions. These results show that propagating trees of the species by air layering is possible and this technique can be used to multiply and keep this species, which will reduce the regeneration problem linked to a low seed germination rate.

Development of the tush and tusk and tusklessness in African elephant (Loxodonta africana)

OpenAIRE

E.J. Raubenheimer

2000-01-01

The embryologic development of the tush and tusk of the African elephant was studied by means of serial histologic sections prepared from elephant embryos with masses varying between Ig and 240 g. Statistics on tusklessness obtained during a four year population control programme in the Kruger National Park were analysed and compared with those reported in other elephant reserves in Southern Africa. Maxillae of eight elephant embryos, the maternal histories of which were available in six case...

Surgical treatment of an umbilical hernia in a free-ranging sub-adult African elephant in Samburu National Reserve, Kenya

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Mijele D

2015-05-01

Full Text Available Domnic Mijele, Michael Njoroge, Titus Kaitho Veterinary Services Department, Species Conservation and Management Division, Kenya Wildlife Service, Nairobi, Kenya Abstract: A 10-year-old male African elephant (Loxodonta africana at Samburu National Reserve in Northern Kenya, weighing approximately 1,600 kg, presented with an umbilical hernia in October 2013. Umbilical herniorrhaphy was carried out under field conditions. Anesthesia was induced and maintained using etorphine hydrochloride for 3 hours during the surgery. This case report details both the surgical and anesthetic procedure carried out to correct the hernia, and the eventual successful recovery of the elephant from anesthesia. However, the elephant died weeks after the surgery and a postmortem could not reveal the cause of death because predators had scavenged the carcass. The challenges of the surgical procedure and outcome including possible causes of death are highlighted in this report. Keywords: African elephant, general anesthesia, etorphine hydrochloride, local anesthesia Lignocaine + adrenaline, umbilical herniorrhaphy

Consumo da costa africana: comunicações entre os portos turísticos sul-africanos do oceano Índico

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Pamila Gupta

2015-12-01

Full Text Available Do início até meados do século XX, os cruzeiros turísticos ao longo da costa sul-africana eram uma atividade de lazer popular, empreendida pelas elites (brancas europeias (predominantemente os britânicos, americanas e sul-africanas, com paradas que incluíam diversas cidades portuárias do oceano Índico, como Cidade do Cabo e Durban, na África do Sul, e Lourenço Marques e Beira, no Moçambique português. Considerando as cidades portuárias anteriormente mencionadas como cidades-gêmeas em relação aos seus entrelaçados passados coloniais e turísticos e como funcionando dentro de um “corredor cultural” regional distinto (NUTALL, 2009 da África do Sul, este artigo explora uma série de portos de lazer interligados via cruzeiros de passageiros. A base da minha navegação histórica são os anuários de turismo produzidos pelas companhias de cruzeiro marítimo Union-Castle Line e serviço Round África em 1939 e 1949, respectivamente. A justificativa é que esses guias de viagem servem como entrada ao microcosmo cosmopolita de barcos de cruzeiro, o que os torna inestimáveis para entender a história do lazer (concomitantemente aos bens de consumo e publicidade relacionados na África do Sul.

One bis-indole alkaloid-voacamine from Voacanga africana Stapf: biological activity evaluation of PTP1B in vitro utilizing enzymology method based on SPRi expriment.

Science.gov (United States)

Wang, Yan-Qiu; Li, Hong-Xiang; Liu, Xiao-Chun; Zhao, Jin-Shuang; Liu, Rong-Qiang; Huai, Wen-Ying; Ding, Wei-Jun; Zhang, Tian-E; Deng, Yun

2018-05-31

One known bis-indole alkaloid-voacamine was isolated from Voacanga africana Stapf and Surface Plasmon Resonance imaging (SPRi) exprement showed that this alkaloid could be combine with Protein Tyrosine Phosphatase1B (PTP1B). Then the PTP1B activity inhibition experiment display that the compound showed an outstanding promoting activity to PTP1B.

Functional and anti-nutritional properties, in-vitro protein digestibility and amino acid composition of dehulled afzelia africana seeds

International Nuclear Information System (INIS)

Ogungbenle, H.N.; Omaejalile, M.

2010-01-01

Analysis of Afzelia africana seed flour showed that the seeds possessed high water absorption capacity (128.31%), good oil absorption capacity (588.49%) and fairly good emulsion property (35.25%). However, it had the Least gelation concentration (6 .00% w/v) and foaming properties ( 8.00%,3 .00%). Anti-nutritional factors were very low, with the highest being phytate (13.59/o) and tannin the least (0.43%). Total amino acid composition was 796.6 mg/g protein. Essentiaal amino acids (48.5%)w ere in high proportion with in-vitro digestibility of 71.5%. (author)

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana.

Science.gov (United States)

Baines, Lydia; Morgan, Eric R; Ofthile, Mphoeng; Evans, Kate

2015-04-01

It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%), and nematode (77%) and trematode (24%) eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685) than in all-male groups (529, sd 468). Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1-15 months. Possible reasons for associations between other factors and infection levels are discussed.

Occurrence and seasonality of internal parasite infection in elephants, Loxodonta africana, in the Okavango Delta, Botswana

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Lydia Baines

2015-04-01

Full Text Available It is known from studies in a wide range of wild and domestic animals, including elephants, that parasites can affect growth, reproduction and health. A total of 458 faecal samples from wild elephants were analysed using a combination of flotation and sedimentation methods. Coccidian oocysts (prevalence 51%, and nematode (77% and trematode (24% eggs were found. Species were not identified, though trematode egg morphology was consistent with that of the intestinal fluke Protofasciola robusta. The following factors were found to have a significant effect on parasite infection: month, year, sex, age, and group size and composition. There was some evidence of peak transmission of coccidia and nematodes during the rainy season, confirmed for coccidia in a parallel study of seven sympatric domesticated elephants over a three month period. Nematode eggs were more common in larger groups and nematode egg counts were significantly higher in elephants living in maternal groups (mean 1116 eggs per gram, standard deviation, sd 685 than in all-male groups (529, sd 468. Fluke egg prevalence increased with increasing elephant age. Preservation of samples in formalin progressively decreased the probability of detecting all types of parasite over a storage time of 1–15 months. Possible reasons for associations between other factors and infection levels are discussed.

Géneros narrativos nas literaturas africanas de língua portuguesa – entre a tradição africana e o “cânone ocidental”

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Inocência Mata

2015-11-01

Full Text Available Depois do golpe de Estado em Portugal, a 25 de Abril de 1974, começámos, nos países africanos ainda colónias de Portugal, a estudar os “nossos” escritores. Andava eu ainda no liceu e naquele tempo não me lembro de termos estudado autores brasileiros e muito menos africanos. Por isso, na altura, uma questão que me intrigou q uando tive contacto com os primeiros textos africanos, foi a palavra estória – em vez de conto – para referir narrativas curtas. Primeiro pensei tratar-se de mais um “africanismo” (explicação então em voga para qualquer “desvio”; depois, quando fui aprofundando o estudo das literaturas africanas, na Faculdade de Letras da Universidade de Lisboa, como aluna do Professor Manuel Ferreira, esta questão nunca foi referida como “problema” e, por isso, a designação “naturalizou-se”… Até que me tornei estudiosa dessas literaturas, já então conhecedora da presença do termo na literatura brasileira.

Impact of fresh and saline water flooding on leaf gas exchange in two Italian provenances of Tamarix africana Poiret.

Science.gov (United States)

Abou Jaoudé, R; de Dato, G; Palmegiani, M; De Angelis, P

2013-01-01

In Mediterranean coastal areas, changes in precipitation patterns and seawater levels are leading to increased frequency of flooding and to salinization of estuaries and freshwater systems. Tamarix spp. are often the only woody species growing in such environments. These species are known for their tolerance to moderate salinity; however, contrasting information exists regarding their tolerance to flooding, and the combination of the two stresses has never been studied in Tamarix spp. Here, we analyse the photosynthetic responses of T. africana Poiret to temporary flooding (45 days) with fresh or saline water (200 mm) in two Italian provenances (Simeto and Baratz). The measurements were conducted before and after the onset of flooding, to test the possible cumulative effects of the treatments and effects on twig aging, and to analyse the responses of twigs formed during the experimental period. Full tolerance was evident in T. africana with respect to flooding with fresh water, which did not affect photosynthetic performances in either provenance. Saline flooding was differently tolerated by the two provenances. Moreover, salinity tolerance differently affected the two twig generations. In particular, a reduction in net assimilation rate (-48.8%) was only observed in Baratz twigs formed during the experimental period, compared to pre-existing twigs. This reduction was a consequence of non-stomatal limitations (maximum carboxylation rate and electron transport), probably as a result of higher Na transport to the twigs, coupled with reduced Na storage in the roots. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

Effet de prétraitements des semences sur la germination de Prosopis africana (Guill., Perrot. et Rich. Taub., (Césalpiniacées

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M'po Ifonti M'po

2009-01-01

Full Text Available Effect of Seed Treatments on the Germination of Iron Tree Prosopis africana (Guill., Perrot. et Rich. Taub. The effect of four seed treatments (i soaking in concentrate sulphuric acid for 15 mn, (ii soaking in hot water at 100 oC for 3 mm followed by in immersion into tap water for 24 hours, (iii scarification with razor blade (iv no treatment on the germination of Prosopis africana seeds was evaluated on two types of growing substrate: erosion sand and ferrallitic soil. Non treated seeds gave the highest rates of germination on the two types of growing substrate (100% on erosion sand and 89% on ferrallitic soil and by much longer duration of germination compared to treated seeds (46 days on erosion sand and 42 days on ferrallitic soil. Overall, germination is better (rates and speed on erosion sand. Treatments of the seeds in concentrate sulphuric acid are prejudicial to the survival of the embryo and yield low germination rates (30% on erosion sand and 20% on ferrallitic soil. Scarification by razor blade and soaking in hot water at 100 oC gave the highest germination rate (85%, 18 days after sowing on erosion sand and allowed to accelerate the germination. Because of their simplicity and their low cost, these two seed treatments can be recommended for planters and the use of erosion sand for the sowing.

Monitoring and controlling ovarian activity in elephants.

Science.gov (United States)

Thitaram, Chatchote; Brown, Janine L

2018-03-15

Both Asian (Elephas maximus) and African (Loxodonta africana) elephants are important keystone, umbrella and flagship species. Paradoxically, world population numbers of both species are declining in many of their natural ranges due mainly to poaching, while over population of elephants in some areas is resulting in serious human-elephant conflict, and modifications of natural habitats that impact biodiversity. Understanding mechanisms of reproductive control is vital to effective population management, and for that reason significant advances have been made in endocrine and ultrasonographic monitoring techniques, particularly in studies of elephants ex situ. However, there remains a need to develop new methods to control ovarian activity, both for enhancing and inhibiting reproduction, to maintain population numbers at levels that ensure species survival and their ability to safely cohabitate with humans and other species. We present an overview of reproductive monitoring methods and how they have contributed to our knowledge of elephant reproductive biology, as well as their application for in situ and ex situ conservation purposes. Copyright © 2017 Elsevier Inc. All rights reserved.

Continent-wide survey reveals massive decline in African savannah elephants.

Science.gov (United States)

Chase, Michael J; Schlossberg, Scott; Griffin, Curtice R; Bouché, Philippe J C; Djene, Sintayehu W; Elkan, Paul W; Ferreira, Sam; Grossman, Falk; Kohi, Edward Mtarima; Landen, Kelly; Omondi, Patrick; Peltier, Alexis; Selier, S A Jeanetta; Sutcliffe, Robert

2016-01-01

African elephants (Loxodonta africana) are imperiled by poaching and habitat loss. Despite global attention to the plight of elephants, their population sizes and trends are uncertain or unknown over much of Africa. To conserve this iconic species, conservationists need timely, accurate data on elephant populations. Here, we report the results of the Great Elephant Census (GEC), the first continent-wide, standardized survey of African savannah elephants. We also provide the first quantitative model of elephant population trends across Africa. We estimated a population of 352,271 savannah elephants on study sites in 18 countries, representing approximately 93% of all savannah elephants in those countries. Elephant populations in survey areas with historical data decreased by an estimated 144,000 from 2007 to 2014, and populations are currently shrinking by 8% per year continent-wide, primarily due to poaching. Though 84% of elephants occurred in protected areas, many protected areas had carcass ratios that indicated high levels of elephant mortality. Results of the GEC show the necessity of action to end the African elephants' downward trajectory by preventing poaching and protecting habitat.

Continent-wide survey reveals massive decline in African savannah elephants

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Michael J. Chase

2016-08-01

Full Text Available African elephants (Loxodonta africana are imperiled by poaching and habitat loss. Despite global attention to the plight of elephants, their population sizes and trends are uncertain or unknown over much of Africa. To conserve this iconic species, conservationists need timely, accurate data on elephant populations. Here, we report the results of the Great Elephant Census (GEC, the first continent-wide, standardized survey of African savannah elephants. We also provide the first quantitative model of elephant population trends across Africa. We estimated a population of 352,271 savannah elephants on study sites in 18 countries, representing approximately 93% of all savannah elephants in those countries. Elephant populations in survey areas with historical data decreased by an estimated 144,000 from 2007 to 2014, and populations are currently shrinking by 8% per year continent-wide, primarily due to poaching. Though 84% of elephants occurred in protected areas, many protected areas had carcass ratios that indicated high levels of elephant mortality. Results of the GEC show the necessity of action to end the African elephants’ downward trajectory by preventing poaching and protecting habitat.

Well-Being Impacts of Human-Elephant Conflict in Khumaga, Botswana: Exploring Visible and Hidden Dimensions

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Allison L Mayberry

2017-01-01

Full Text Available High densities of wild African savannah elephants (Loxodonta africana combined with widespread human land-use have increased human-elephant conflict in northern Botswana. Visible impacts (e.g. crop/property damage, injury/fatality of elephants on human well-being are well documented in scholarly literature while hidden impacts (e.g. emotional stress, restricted mobility are less so. This research uses qualitative methods to explore human experiences with elephants and perceived impacts of elephants on human well-being. Findings reveal participants are concerned about food insecurity and associated visible impacts of elephant crop raids. Findings also reveal participants are concerned about reduced safety and restricted mobility as hidden impacts threatening livelihoods and everyday life. Both visible and hidden impacts of elephants contribute to people's negative feelings towards elephants, as does the broader political context. This research emphasises the importance of investigating both visible and hidden impacts of elephants on human well-being to foster holistic understanding of human-elephant conflict scenarios and to inform future mitigation strategies.

Antioxidant activity of ethanolic extract of inflorescence of Ormenis Africana in vitro and in cell cultures

Science.gov (United States)

2011-01-01

Background The antioxidant potency of the hydroethanolic extract of Ormenis Africana (HEOA), Asteraceae was evaluated with regards to total polyphenol, flavonoid and anthocyanins content. Antioxidant activity has been assessed chemically and biologically. First, the free radical scavenging ability of HEOA was evaluated using two commonly in vitro tests: ABTS and DPPH radicals. Then, the protection effect of this extract against oxidative stress was conducted in HeLa cells treated with Fe2+ or H2O2. Oxidative stress was evaluated by measuring the lipid peroxidation levels (TBARs and DC) and the antioxidant enzymes activities (catalase and Superoxide dismutase). Cytotoxic effect of HEOA was prealably determined against HeLa cell line by MTT assay. Results HEOA contain considerable levels of antioxidant compound as evidenced by high amount of polyphenols (312.07 mg GAE/g dray matter), flavonoids (73.72 ± 1.98 mg QE/g dray matterl) and anthocyanins (0.28 ± 0.09 mg Cy-3-glu E/g dray matter). DPPH and ABTS assays showed a high antioxidant activity (IC50 = 24 μg/ml; TEAC = 2.137 mM) which was comparable to BHT. In biological system, HEOA exhibited a 50% cytotoxic concentration evaluated as 16.52 μg/ml. Incubation of HeLa cell line with no cytotoxic concentrations resulted in a remarkable protection from oxidative stress induced by Fe2+ or H2O2 which was evidenced by a decrease of MDA and CD levels as well as a diminution of antioxidant enzymes activities (Catalase and SOD) as compared to cells treated with Fe2+ or H2O2 alone. Conclusion The hydroethanolic extract of O. Africana could thus be considered as a source of potential antioxidants. The results of this study will promote the reasonable usage of this plant in food and pharmacy industries as well as in alternative medicine and natural therapy. PMID:21575256

Isolation of a Novel Fusogenic Orthoreovirus from Eucampsipoda africana Bat Flies in South Africa

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Petrus Jansen van Vuren

2016-02-01

Full Text Available We report on the isolation of a novel fusogenic orthoreovirus from bat flies (Eucampsipoda africana associated with Egyptian fruit bats (Rousettus aegyptiacus collected in South Africa. Complete sequences of the ten dsRNA genome segments of the virus, tentatively named Mahlapitsi virus (MAHLV, were determined. Phylogenetic analysis places this virus into a distinct clade with Baboon orthoreovirus, Bush viper reovirus and the bat-associated Broome virus. All genome segments of MAHLV contain a 5' terminal sequence (5'-GGUCA that is unique to all currently described viruses of the genus. The smallest genome segment is bicistronic encoding for a 14 kDa protein similar to p14 membrane fusion protein of Bush viper reovirus and an 18 kDa protein similar to p16 non-structural protein of Baboon orthoreovirus. This is the first report on isolation of an orthoreovirus from an arthropod host associated with bats, and phylogenetic and sequence data suggests that MAHLV constitutes a new species within the Orthoreovirus genus.

Evaluación agronómica y nutricional del pasto estrella africana (cynodon nlemfuensis En la zona de monte verde, puntarenas, Costa Rica. II. valor nutricional

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Luis Villalobos

2014-01-01

Full Text Available Se analizó el valor nutricional del pasto estrella africana ( Cynodon nlemfuensis a lo largo de 2 años en muestreos bimensuales, en 4 fincas comerciales de ganado lechero ubicadas en los cantones de Tilarán y Central (latitud 10°20’ N, longitud 84°50’, altitud 800 a 1200 msnm de las provincias de Guanacaste y Puntarenas, respectivamente. Las muestras se recolectaron en el aparto siguiente a ser pastoreado y se utilizó una altura de cosecha de 10 cm, para simular el pastoreo que hacen los animales. La composición nutricional promedio para los 2 años de evalua - ción fue de 23,57% MS, 20,27% PC, 2,67% EE, 10,97% cenizas, 64,21% FDN, 34,95% FDA, 4,06% lignina y 68,02% DIVMS y su contenido energético para las variables de TND, ED, EM, EN L (3X y EN G fue 61,37%; 2,71; 2,05; 1,25 y 0,78 Mcal.kg -1 de MS, respectivamente. El valor nutricional del pasto estrella africana varió a lo largo del año como resultado de la climatología de la zona de Monteverde, siendo las fincas con influencia de la vertiente del Pacífico las de menor afectación en la calidad del forraje. El pasto estrella africana mostró un contenido de PC superior a lo reportado para dicha especie y, en general, para pastos tropicales, por lo cual no es limitante para la producción láctea, y la suplementación del ganado lechero en la zona debe utilizar fuentes que permitan una utiliza - ción eficiente del N soluble a nivel ruminal. La rotación del pasto estrella cada 25 días debe ser flexible para permitir, en conjunto con programas de fertilización, optimizar la productividad de las pasturas y su persistencia.

El proyecto político afroperuano: ¿La reivindicación de una diáspora africana sin África?; O projeto político afro-peruano: A reivindicação de uma diáspora africana sem África?; The Afro-Peruvian Political Project: The claim of an African diaspora without Africa?

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Juan Enrique Pozada Pineda

2015-07-01

Full Text Available Resumen: Cuando nos referimos a los términos “diáspora africana”, “afrodescendencia” o “afrodescendientes”, inevitablemente debemos hacer referencia a África. En función a ello, África, podría entenderse como la raíz y el origen de estas tres dimensiones identitarias. En el caso del Perú, específicamente con el proyecto político étnico enarbolado por las organizaciones de derechos civiles afroperuanas y por algunas entidades del Estado especializadas en “lo afroperuano”, las reivindicaciones de una afrodescendencia o pertenencia a una diáspora africana, no suelen dirigirse a África, sino a sus pares afrodescendientes más próximos. Esto como si el Océano Atlántico fuese un gran abismo entre dos mundos muy distintos: el afrodescendiente y el africano. El presente trabajo pretende dar un acercamiento a esta realidad, en donde las luchas por la reivindicación de una diáspora africana se presentan sin África, sin lo africano, desarraigadas de su raíz, aunque sí, con un “África” imaginada, más “cercana” y menos “extraña”.   Palabras clave: Afroperuanos, diáspora, africanidades, proyectos identitarios, afrodescendencia.       Resumo: Quando nos referimos     aos termos "diáspora africana", "afrodescendência" ou "afrodescendentes", inevitavelmente devemos fazer referência à África. Em função disso, se podia entender a África como a raiz e origem destas três dimensões identitárias. No caso do Perú, especificamente com o projeto étnico-político elaborado pelas organizações de direitos civis afro- peruanas e por algumas entidades do Estado especializadas no "afroperuano", as reivindicações de uma afrodescendência ou pertença a uma diáspora africana, normalmente não para dirigir-se a África, se não a seus pares afrodescendentes     mais próximos. Isto como se o oceano Atlântico fosse um grande abismo entre dois mundos distintos: o do afrodescendente e o do africano. O

Fine-scale genetic structure and cryptic associations reveal evidence of kin-based sociality in the African forest elephant.

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Schuttler, Stephanie G; Philbrick, Jessica A; Jeffery, Kathryn J; Eggert, Lori S

2014-01-01

Spatial patterns of relatedness within animal populations are important in the evolution of mating and social systems, and have the potential to reveal information on species that are difficult to observe in the wild. This study examines the fine-scale genetic structure and connectivity of groups within African forest elephants, Loxodonta cyclotis, which are often difficult to observe due to forest habitat. We tested the hypothesis that genetic similarity will decline with increasing geographic distance, as we expect kin to be in closer proximity, using spatial autocorrelation analyses and Tau K(r) tests. Associations between individuals were investigated through a non-invasive genetic capture-recapture approach using network models, and were predicted to be more extensive than the small groups found in observational studies, similar to fission-fusion sociality found in African savanna (Loxodonta africana) and Asian (Elephas maximus) species. Dung samples were collected in Lopé National Park, Gabon in 2008 and 2010 and genotyped at 10 microsatellite loci, genetically sexed, and sequenced at the mitochondrial DNA control region. We conducted analyses on samples collected at three different temporal scales: a day, within six-day sampling sessions, and within each year. Spatial autocorrelation and Tau K(r) tests revealed genetic structure, but results were weak and inconsistent between sampling sessions. Positive spatial autocorrelation was found in distance classes of 0-5 km, and was strongest for the single day session. Despite weak genetic structure, individuals within groups were significantly more related to each other than to individuals between groups. Social networks revealed some components to have large, extensive groups of up to 22 individuals, and most groups were composed of individuals of the same matriline. Although fine-scale population genetic structure was weak, forest elephants are typically found in groups consisting of kin and based on matrilines

Antibacterial activity of crude methanolic extract and various fractions of Vitex agnus castus and Myrsine africana against clinical isolates of Methicillin Resistant Staphylococcus aureus.

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Ahmad, Bashir; Hafeez, Nabia; Ara, Gulshan; Azam, Sadiq; Bashir, Shumaila; Khan, Ibrar

2016-11-01

Staphylococcus aureus is a nosocomial pathogen that resides in the soft tissues causing many diseases. The current study was conducted to determine the prevalence of Methicillin Resistant S. aureus (MRSA) in ear discharge and pus of patients and antibacterial activity of crude methanolic extract (Cr. MeOH Ext.) and various fractions of M. Africana and V. agnus castus against clinical isolates of MRSA. A total of 40 samples were collected from ear, nose and throat (ENT) outpatient department and wards of Khyber Teaching Hospital (KTH), Peshawar. Out of 40 samples, 36 (90%) samples showed growth on Mannitol Salt Agar (MSA) media out of which 9(25%) were MRSA and the remaining 27(75%) were methicillin susceptible S. aureus (MSSA). A good antibacterial activity was observed for the Cr. MeOH Ext. (76.1%) and ethyl acetate (EtOAc) fraction of V. agnus castus against S11 (71.4%). The n-hexane fraction also showed good antibacterial effect (70%) against S 26 . The chloroform (CHCl3), butanol (BuOH) and aqueous fractions of M. africana showed good antibacterial activity against S 11 (71.4%), S32 (70%) and S 26 (75%), respectively. The above results revealed that the selected plants can be further utilized for isolation of the active ingredients as the crude extracts were found good for inhibition of MRSA.

Aspects of elephant behavior, ecology, and interactions with humans

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O'Connell, Caitlin Elizabeth

This dissertation is comprised of two chapters relating to the acoustic behavior of elephants, their surrounding ecology and interactions with humans. The first chapter investigates the seismic aspects of Asian elephant (Elephus maximus) acoustic communication. The second chapter is comprised of a synthesis of two separate studies conducted on the African elephant (Loxodonta africana) in Namibia, both in Etosha National Park and the Caprivi region. The two studies were combined and published in Biological Conservation as one large study on aspects of the economic and social impacts of elephant/human conflict and experiments conducted to reduce conflict. In chapter one, seismic and acoustic data were recorded simultaneously from Asian elephants during periods of vocalizations and locomotion. Acoustic and seismic signals from rumbles were highly correlated at near and far distances and were in phase near the elephant and were out of phase at an increased distance from the elephant. Data analyses indicated that elephant generated signals associated with rumbles and "foot stomps" propagated at different velocities in the two media, the acoustic signals traveling at 309 m/s and the seismic signals at 248--264 m/s. Both types of signals had predominant frequencies in the range of 20 Hz. Seismic signal amplitudes considerably above background noise were recorded at 40 m from the generating elephants for both the rumble and the stomp. Seismic propagation models suggest that seismic waveforms from vocalizations are potentially detectable by instruments at distances of up to 16 km, and up to 32 km for locomotion generated signals. Thus, if detectable by elephants, these seismic signals could be useful for long distance communication. In chapter two, the economic impact of elephants, Loxodonta africana , and predators, particularly lions, Panthera leo, on rural agriculturists in the Kwando region of the East Caprivi, Namibia was assessed from the years 1991 to 1995. Elephants

Calorific value of Prosopis africana and Balanites aegyptiaca wood: Relationships with tree growth, wood density and rainfall gradients in the West African Sahel

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Montes, Carmen Sotelo; Weber, John C. [World Agroforestry Centre (ICRAF), Sahel Office, B.P. E 5118 Bamako (Mali); Silva, Dimas Agostinho da; Bolzon de Muniz, Graciela Ines [Universidade Federal do Parana (UFPR), Av. Lothario Meissner, 900, CEP.: 80270-170-Curitiba (Brazil); Garcia, Rosilei A. [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Instituto de Florestas, Departamento de Produtos Florestais, BR 465, km 07, 23890-000, Seropedica, Rio de Janeiro (Brazil)

2011-01-15

Prosopis africana and Balanites aegyptiaca are native tree species in the West African Sahel and provide wood for fuel, construction and other essential products. A provenance/progeny test of each species was established at one relatively dry site in Niger, and evaluated at 13 years. Gross calorific value of the wood was determined for a random sample of trees in each test: gross CV and CVm{sup 3} = gross calorific value in MJ kg{sup -1} and MJ m{sup -3}, respectively. The major objectives were to determine if gross CV was positively correlated with wood density and tree growth, and if gross CV and/or CVm{sup 3} varied with rainfall gradients in the sample region. Provenances were grouped into a drier and more humid zone, and correlations were computed among all trees and separately in each zone. Results indicated that gross CV was not significantly correlated with density in either species. Gross CV was positively correlated with growth of P. africana (but not B. aegyptiaca) only in the drier zone. Gross CVm{sup 3} was positively correlated with growth of both species, and the correlations were stronger in the drier zone. Multiple regressions with provenance latitude, longitude and elevation indicated that provenance means for gross CV increased, in general, from the drier to the more humid zones. Regressions with gross CVm{sup 3} were not significant. Results are compared with earlier research reports from the provenance/progeny tests and with other tropical hardwood species; and practical implications are presented for tree improvement and conservation programs in the region. (author)

Rhythm experience and Africana culture trial (REACT!): A culturally salient intervention to promote neurocognitive health, mood, and well-being in older African Americans.

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Lukach, Alexis J; Jedrziewski, M Kathryn; Grove, George A; Mechanic-Hamilton, Dawn J; Williams, Shardae S; Wollam, Mariegold E; Erickson, Kirk I

2016-05-01

The Rhythm Experience and Africana Culture Trial (REACT!) is a multi-site randomized controlled intervention study designed to examine the efficacy of using African Dance as a form of moderate-intensity physical activity to improve cognitive function in older African Americans. African Americans are almost two times more likely than Caucasians to experience cognitive impairment in late adulthood. This increased risk may be attributed to lower level and quality of education, lower socioeconomic status, and higher prevalence of vascular diseases, type 2 diabetes, hypertension, and obesity, all of which are recognized as risk factors for dementia. Fortunately, interventions targeting cardiovascular health (i.e., physical activity) are associated with improved neurocognitive function and a reduced risk for dementia, so African Americans may be particularly suited for interventions targeting cardiovascular health and cognitive function. Here, we describe a randomized intervention protocol for increasing physical activity in older (65-75years) African Americans. Participants (n=80) at two study locations will be randomized into one of two groups. The treatment group will participate in African Dance three times per week for six months and the control group will receive educational training on Africana history and culture, as well as information about health behaviors, three times per week for six months. If successful, the REACT! study may transform community interventions and serve as a platform and model for testing other populations, age groups, and health outcomes, potentially identifying novel and creative methods for reducing or eliminating health disparities. Copyright © 2016 Elsevier Inc. All rights reserved.

Effet du biotope sur la diversité floristique et le polymorphisme phénotypique des groupements à Tamarix africana Poir. dans les zones arides de la région de Khenchela (Est Algerien

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Khabtane Abdelhamid

2012-12-01

Full Text Available RESUME Le genre Tamarix (Tamaricaceae regroupe plus de 80 espèces, parmi eux le Tamarix africana Poir. qui représente une très grande ubiquité en Algérie, soit du point de vue climatique (humidité et sécheresse, édaphique (sols salés et calcaires; où il représente l’espèce  à caractère typique des plantes thermo xérophytes. Pour contribuer à la connaissance de cette espèce et de son comportement nous avons essayé de suivre le comportement  phytosociologique ainsi que sa variabilité morphologique (l’hauteur, le recouvrement basale, nombre des ramifications à la base.. dans trois biotopes, extrêmement différents du point de vue climatique et édaphique,  dans les zones steppiques arides de la région de Khenchela (Est Algérien et qui sont  choisis  selon un transect Nord - Sud. Les résultats révèlent que les groupements à Tamarix africana Poir. représentent une richesse floristique importante, qui se diffère d’un site à l’autre, avec un polymorphisme phénotypique adaptée aux conditions spécifiques à chacun des trois sites et qui lui permet d’être l’espèce à forme arbustive  la plus adaptée pour la réhabilitation des écosystèmes dégradés dans les zones de transitions Désert-NordMots clés Tamarix africana P. - ubiquité- thermo xérophytes-  régions arides- halophytes- polymorphisme phénotypique

Dietary management, husbandry, and body weights of African elephants (Loxodonta africana) during successful pregnancies at Disney's Animal Kingdom.

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Sullivan, Kathleen; Kerr, Katherine; Wanty, Rachel; Amaral, Bryan; Olea-Popelka, Francisco; Valdes, Eduardo

2016-11-01

Successful pregnancy in African elephants is influenced by biological and environmental factors. For managed elephants many of these factors are set directly or indirectly by their human care takers, including nutrition and husbandry. While African elephants often struggle to conceive and produce healthy offspring under human care, Disney's Animal Kingdom (DAK) has effectively managed six gestations to fruition in three cows. Despite differences between mothers in terms of BW and growth curves during gravidity, each pregnancy successfully resulted in the birth of a healthy calf. Body weight (BW) gain during pregnancy ranged from 245 to 558 kg. Obesity in elephants is associated with increased occurrence of dystocia and mortality of the fetus and mother, hence understanding normal weight gains is an integral concept. Diet (dry matter basis) included high levels of fiber throughout pregnancies (60-70% neutral detergent fiber), vitamin E supplementation (116-214 mg/kg diet of alpha-tocopherol), as well as low levels of starch (2.5-5.1%) and crude fat (1.9-2.4%). Caretaker directed exercise during pregnancy at DAK served to prevent ventral edema, and increase muscle tone to prepare cows for parturition. Demonstrating techniques for effective care of pregnant females, as well as normal growth curves and fluctuations under ex situ conditions are necessary for future positive outcomes. Ensuring reproductive success through proper husbandry and nutrition are a key to long-term conservation of elephants. Zoo Biol. 35:574-578, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Tuberculosis serosurveillance and management practices of captive African elephants (Loxodonta africana) in the Kavango-Zambezi Transfrontier Conservation Area.

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Rosen, L E; Hanyire, T G; Dawson, J; Foggin, C M; Michel, A L; Huyvaert, K P; Miller, M A; Olea-Popelka, F J

2018-04-01

Transfrontier conservation areas represent an international effort to encourage conservation and sustainable development. Their success faces a number of challenges, including disease management in wildlife, livestock and humans. Tuberculosis (TB) affects humans and a multitude of non-human animal species and is of particular concern in sub-Saharan Africa. The Kavango-Zambezi Transfrontier Conservation Area encompasses five countries, including Zimbabwe, and is home to the largest contiguous population of free-ranging elephants in Africa. Elephants are known to be susceptible to TB; thus, understanding TB status, exposure and transmission risks to and from elephants in this area is of interest for both conservation and human health. To assess risk factors for TB seroprevalence, a questionnaire was used to collect data regarding elephant management at four ecotourism facilities offering elephant-back tourist rides in the Victoria Falls area of Zimbabwe. Thirty-five working African elephants were screened for Mycobacterium tuberculosis complex antibodies using the ElephantTB Stat-Pak and the DPP VetTB Assay for elephants. Six of 35 elephants (17.1%) were seropositive. The risk factor most important for seropositive status was time in captivity. This is the first study to assess TB seroprevalence and risk factors in working African elephants in their home range. Our findings will provide a foundation to develop guidelines to protect the health of captive and free-ranging elephants in the southern African context, as well as elephant handlers through simple interventions. Minimizing exposure through shared feed with other wildlife, routine TB testing of elephant handlers and regular serological screening of elephants are recommended as preventive measures. © 2017 Blackwell Verlag GmbH.

Information content and acoustic structure of male African elephant social rumbles.

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Stoeger, Angela S; Baotic, Anton

2016-06-08

Until recently, the prevailing theory about male African elephants (Loxodonta africana) was that, once adult and sexually mature, males are solitary and targeted only at finding estrous females. While this is true during the state of 'musth' (a condition characterized by aggressive behavior and elevated androgen levels), 'non-musth' males exhibit a social system seemingly based on companionship, dominance and established hierarchies. Research on elephant vocal communication has so far focused on females, and very little is known about the acoustic structure and the information content of male vocalizations. Using the source and filter theory approach, we analyzed social rumbles of 10 male African elephants. Our results reveal that male rumbles encode information about individuality and maturity (age and size), with formant frequencies and absolute fundamental frequency values having the most informative power. This first comprehensive study on male elephant vocalizations gives important indications on their potential functional relevance for male-male and male-female communication. Our results suggest that, similar to the highly social females, future research on male elephant vocal behavior will reveal a complex communication system in which social knowledge, companionship, hierarchy, reproductive competition and the need to communicate over long distances play key roles.

Conservation challenge: human-herbivore conflict in Chebera Churchura National Park, Ethiopia.

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Datiko, Demeke; Bekele, Afework

2013-12-01

An investigation on human-herbivore conflict was carried out in CCNP between 2011 and 2012 in seven randomly selected villages (Chebera, Serri, Yora, Shita, Delba, Chuchra, Chewda) around the Park. A total of 312 household samples were identified for interview. Group discussion and field observation were also carried out. Among the respondents, the majority (83.9%) faced crop damage. African elephant (Loxodonta africana), Hippopotamus (Hippopotamus amphibious), African buffalo (Syncerus caffer), Desert warthog (Phacochoerus aethiopicus), Wild pig (Sus scrofa), Porcupine (Hystrix cristata), Vervet monkey (Cercopithecus aethiops) and Anubis baboon (Papio anubis) were identified as the most problematic animals in the area. However, buffalo, monkey and warthog were considered as the notorious pest. Crop damage and threats to human safety were the major problems encountered resulting in conflict between human and wildlife. Most respondents had a negative attitude towards the problem-posing animals. This will lead to a change in public attitude from one that supports wildlife conservation to sees wild herbivores as a threat and a potential negative consequence for wildlife conservation. Active measures have to be implemented to solve the problems and safeguard the future of the wildlife management in the park.

Movements and corridors of African elephants in relation to protected areas

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Douglas-Hamilton, I.; Krink, T.; Vollrath, F.

2005-04-01

Understanding how mammals satisfy their need for space in fragmenting ecosystems is crucial for ecosystem conservation. Using state-of-the-art global positioning system (GPS) technology we tracked 11 focal African elephants (Loxodonta africana) in Kenya at 3-hourly fix intervals and collected between 34 and 406 days per individual. Our recordings gave a high spatio-temporal resolution compared to previous studies and allowed novel insights into range use. The actual ranges of the tracked elephants are smaller than usually represented. Moreover, the ranges in our sample were complex and not confined to officially designated protected areas, except where fenced. All the unfenced elephants in our sample had distinct `home sectors' linked by `travel' corridors. Within each home sector the elephants concentrated in favourite `core zones'. Such core zones tended to lie in protected areas whereas corridors typically crossed unprotected range. Elephants moved significantly faster along corridors than elsewhere in their range, which suggests awareness of danger outside the protected area. We conclude that understanding the complex use of an animal's range is crucial for conservation planning aiming to balance animal interests with those of human beings that co-habit in their range.

Evolutionary and demographic processes shaping geographic patterns of genetic diversity in a keystone species, the African forest elephant (Loxodonta cyclotis).

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Ishida, Yasuko; Gugala, Natalie A; Georgiadis, Nicholas J; Roca, Alfred L

2018-05-01

The past processes that have shaped geographic patterns of genetic diversity may be difficult to infer from current patterns. However, in species with sex differences in dispersal, differing phylogeographic patterns between mitochondrial (mt) and nuclear (nu) DNA may provide contrasting insights into past events. Forest elephants ( Loxodonta cyclotis ) were impacted by climate and habitat change during the Pleistocene, which likely shaped phylogeographic patterns in mitochondrial (mt) DNA that have persisted due to limited female dispersal. By contrast, the nuclear (nu) DNA phylogeography of forest elephants in Central Africa has not been determined. We therefore examined the population structure of Central African forest elephants by genotyping 94 individuals from six localities at 21 microsatellite loci. Between forest elephants in western and eastern Congolian forests, there was only modest genetic differentiation, a pattern highly discordant with that of mtDNA. Nuclear genetic patterns are consistent with isolation by distance. Alternatively, male-mediated gene flow may have reduced the previous regional differentiation in Central Africa suggested by mtDNA patterns, which likely reflect forest fragmentation during the Pleistocene. In species like elephants, male-mediated gene flow erases the nuclear genetic signatures of past climate and habitat changes, but these continue to persist as patterns in mtDNA because females do not disperse. Conservation implications of these results are discussed.

Evaluación agronómica y nutricional del pasto EStrella africana (Cynodon nlemfuensis en la zona de monteverde, puntarenas, Costa Rica. I. DISPONIBILIDAD DE BIOMASA Y FENOLOGÍA

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Luis Villalobos

2013-01-01

Full Text Available Se evaluó la disponibilidad de biomasa y la fenología del pasto estrella africana (Cynodon nlemfuensis a lo largo de 2 años en muestreos bimensuales, en 4 fincas comerciales de ganado lechero ubicadas en los cantones de Tilarán y Central (latitud 10°20’ N, longitud 84°50’ O,altitud 800 a 1200 msnm de las provincias de Guanacaste y Puntarenas, respectivamente. La disponibilidad de materia seca pre-pastoreo y laedad fenológica promedio fueron 4484 kg.ha-1. corte-1 y 7,36 hojas verdes por rebrote, respec- tivamente. La composición botánica promediode las pasturas fue 86,81% estrella, 2,52% otrasgramíneas, 1,39% leguminosas, 1,53% malezas y 7,75% material senescente. La disponibilidad de biomasa fue mayor en las fincas con influencia climática del Oceano Pacífico y su producción disminuyó en los meses de mayor precipitación. La edad fenológica del pasto estrella africana se ubica entre 6 y 8 hojas verdes por rebrote, lo cual permite una adecuada recuperación del pasto, y disminuyó en los meses con excesos deprecipitación.

Evaluation of Antibacterial and Antioxidant Activity of Leaves, Fruit and Bark of Kigelia Africana

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Fatima, I.; Shabir, S.; Bano, S.

2016-01-01

In vitro antibacterial activity of extracts was tested against six bacterial strains viz. Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Citrobacter amalonaticus by agar-disc diffusion method. Ethanol and n-hexane were used as negative control and oxytetracycline was used as a positive control. Ethanolic and aqueous extracts of bark and leaves of Kigelia africana showed remarkable activity against various bacterial strains as compared to n-hexane. S. aureus and E. coli were proved as highly sensitive strains while K. pneumonia was the resistant strain as the extracts formed no inhibition zone against it. The percentage of antioxidant activity of different parts of Kigelia was assessed by DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical assay. Quercetin was used as a standard antioxidant which showed 93.6 percent inhibition. Kigelia bark extract showed good antioxidant activity i.e., 67.33 percent inhibition, fruit extract possess moderate antioxidant activity i.e., 62.66 percent inhibition while leaves showed the poor antioxidant activity i.e., 59.66 percent DPPH inhibition respectively. Overall, the comparative analysis revealed that bark extract exhibited the most remarkable antibacterial as well as antioxidant activity as compared to leaves and fruit extracts. (author)

The hypolipidemic effects of Afzelia africana in type II diabetic patients in Nigeria.

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Nwosu, M C; Odenigbo, U M; Odenigbo, U C

2006-01-01

The projected rise in the world prevalence of diabetes mellitus poses new challenges in poor countries. Soluble fibre incorporation into the diet of diabetic patients has been shown to reduce the glyceamia and lipaemia of diabetes mellitus. The hypolipidemic effect of soluble fibre supplementation using the seed of locally available legume tree plant--Afzelia africana was studied in 13 Nigerian patients with type 2 diabetes mellitus. The subjects were randomly selected from the out patient diabetes mellitus clinic of Nnamdi Azikiwe University Teaching Hospital, Nnewi. They were fed with unsupplemented and supplemented standardized diet for the first 2 days and subsequent 4 days respectively. The fibre supplementation was prepared and incorporated into the meal portions according to previously described technique and acceptability study. The fasting serum levels of TC, TG, HDL-C, LDL-C and HDL/TC ratio were estimated before and after the unsupplemented and fibre supplemented meals. The data obtained were analyzed using paired t-test. The correlation between the total energy requirement and the reduction in TC, pre and post fibre supplemented meals were determined using the linear coefficients. The results showed a significant reduction (P 0.05). The exploitation and incorporation of this source of soluble fibre in diabetic diets reduced the lipaemia of diabetes mellitus.

Evaluación del cuesco de palma africana y del carbón del cerrejón para producir carbón activado

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Anundo Polanía León

2010-05-01

Full Text Available Se produjeron carbones activados a partir de carbón de El Cerrejón y del Cuesco de Palma Africana mediante activación con vapor de agua y KOH, a 700 y 800 ó 900°C variando la relación activante/carbonizado y el tiempo de activación. Los tiempos de activación a los que se desarrolla mayor área superficial son mucho más cortos con el vapor de agua que con el KOH. Al activar con este último se obtienen valores de área superficial similares errlas dos materias primas, según la temperatura de trabajo, mientras que la activación con vapor de agua, presenta características totalmente diferentes. La activación del Cuesco de Palma Africana con KOH, produce carbones esencialmente microporosos, mientras que con vapor de agua, produce carbones activados con una apreciable mesoporosidad favorecida por el incremento de la temperatura. La activación del carbón de El Cerrejón con KOH o vapor de agua produce carbones activados microporosos. En líneas generales se puede decir que el tipo de textura porosa obtenida en la producción de un carbón activado, es función no sólo de los agentes activantes utilizados, sino también del tipo u origen de la materia prima, mientras que la calidad del carbón activado, (área superficial total, es función del tiempo y de la temperatura de activación, al menos con los materiales de partida usados en este trabajo.

Development of a novel set of EST-SSR markers and cross-species amplification in Tamarix africana (Tamaricaceae).

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Terzoli, Serena; Beritognolo, Isacco; Sabatti, Maurizio; Kuzminsky, Elena

2010-06-01

Tamarix plants are resistant to abiotic stresses and have become invasive in North America. Their taxonomy is troublesome, and few molecular makers are available to enable species identification or to track the spread of specific invasive genotypes. Transcriptome sequencing projects offer a potential source for the development of new markers. • Thirteen polymorphic simple sequence repeats (SSRs) markers derived from Expressed Sequence Tags (ESTs) from Tamarix hispida, T. androssowii, T. ramosissima, and T. albiflonum were identified and screened on 24 samples of T. africana to detect polymorphism. The number of alleles per locus ranged from two to eight, with an average of 4.3 alleles per locus, and the mean expected heterozygosity was 0.453. • Amplification products of these 13 loci were also generated for T. gallica. These new EST-SSR markers will be useful in genetic characterization of Tamarix, as additional tools for taxonomic clarification, and for studying invasive populations where they are a threat.

COMPORTAMENTO DA Cordia africana Lam. CULTIVADA EM SOLO CONTAMINADO POR METAIS PESADOS E TRATADO COM MATERIAIS AMENIZANTES

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Ana Carolina Callegario Pereira

2013-01-01

Full Text Available This study aimed to evaluate the remediation of two soils contaminated with heavy metals from soil excavations, located near the port of Itaguaí, through the techniques of chemical immobilization and phytostabilization using the species Cordia africana. The data were collected in the ore courtyard from ‘Companhia Siderúgica Nacional’ (CSN, in the port of Itaguaí, Rio de Janeiro state. In order to reduce the solubility of heavy metals present in these substrates, two industrial waste products produced by CSN were used as ameliorating products, the steelmaking slag and the mill scale, in different concentrations. The plant species was considered with potential to be used in programs of phytostabilization, due to its heavy metal tolerance studied and to high accumulation of such elements in roots and stem. In the substrate of low combination, the lowest accumulation of zinc and cadmium in stems and leaves occurred with the use of 4% of soothing. In the substrate of high accumaltion it was 6%.

Effects of daily management changes on behavioral patterns of a solitary female African elephant (Loxodonta africana) in a zoo.

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Koyama, Nao; Ueno, Yoshikazu; Eguchi, Yusuke; Uetake, Katsuji; Tanaka, Toshio

2012-07-01

This study investigated the effects of changes in daily management on behavior of a solitary female elephant in a zoo. The activity budget and space utilization of the subject and the management changes were recorded for 1 year after the conspecific male died. The observation days could be categorized into five clusters (C1-C5) by the characteristic behavioral pattern of each day. C1 had the highest percentage of resting of all clusters, and was observed after the loss of the conspecific and the beginning of use of the indoor exhibition room at night. C2, which had the highest percentage of stereotypy of any cluster, was observed after the beginning of habituation to the indoor exhibition room. Also, when the time schedule of management was changed irregularly, the subject frequently exhibited stereotypic pacing (C2, C4). The subject tended to rest when exhibiting lameness in the left hind limb (C3). In C5, activity reached a high level when she could utilize a familiar place under a stable management schedule. These results indicate that management changes affected the mental stability of an elephant in the early stage of social isolation. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.

Fine-scale genetic structure and cryptic associations reveal evidence of kin-based sociality in the African forest elephant.

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Stephanie G Schuttler

Full Text Available Spatial patterns of relatedness within animal populations are important in the evolution of mating and social systems, and have the potential to reveal information on species that are difficult to observe in the wild. This study examines the fine-scale genetic structure and connectivity of groups within African forest elephants, Loxodonta cyclotis, which are often difficult to observe due to forest habitat. We tested the hypothesis that genetic similarity will decline with increasing geographic distance, as we expect kin to be in closer proximity, using spatial autocorrelation analyses and Tau K(r tests. Associations between individuals were investigated through a non-invasive genetic capture-recapture approach using network models, and were predicted to be more extensive than the small groups found in observational studies, similar to fission-fusion sociality found in African savanna (Loxodonta africana and Asian (Elephas maximus species. Dung samples were collected in Lopé National Park, Gabon in 2008 and 2010 and genotyped at 10 microsatellite loci, genetically sexed, and sequenced at the mitochondrial DNA control region. We conducted analyses on samples collected at three different temporal scales: a day, within six-day sampling sessions, and within each year. Spatial autocorrelation and Tau K(r tests revealed genetic structure, but results were weak and inconsistent between sampling sessions. Positive spatial autocorrelation was found in distance classes of 0-5 km, and was strongest for the single day session. Despite weak genetic structure, individuals within groups were significantly more related to each other than to individuals between groups. Social networks revealed some components to have large, extensive groups of up to 22 individuals, and most groups were composed of individuals of the same matriline. Although fine-scale population genetic structure was weak, forest elephants are typically found in groups consisting of kin and

História e Cultura Afro-Brasileira e Africana na Educação Básica da Paraíba

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Waldeci Ferreira Chagas

2017-01-01

Full Text Available Neste artigo discute-se sobre o ensino de história e cultura afro-brasileira e africana em escolas públicas da Paraíba. Nele analisam-se as experiências desenvolvidas por trinta docentes que atuam na educação básica e em escolas públicas municipais localizadas em cidades de três mesorregiões da Paraíba: litoral, agreste e brejo. Para a realização da análise, recorreu-se aos projetos desenvolvidos e executados pelos docentes, através dos quais foi discutido o conteúdo, a metodologia, os recursos didáticos e a relação entre a execução desses projetos e a efetivação da educação para as relações étnico-raciais.

Pedagogias do corpo na educação da dança de matriz africana em Salvador, BA, Brasil: perspectivas e tensões do projeto emancipatório

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Echeverry Zambrano, Claudia Del Pilar

2013-01-01

212 f. Esta tese, resultado de uma pesquisa de caráter etnográfico e bibliográfico, analisa as pedagogias usadas na educação do corpo, dentro da proposta das danças de matriz africana, que são praticadas em ambientes escolares em Salvador, Bahia, Brasil. O estudo faz uma ênfase na descrição das perspectivas e desafios que esta educação enfrenta na atualidade como projeto corporal emancipador e reestruturador das representações sobre o corpo negro, historicamente configuradas no marco moder...

Hilos descoloniales. Trans-localizando los espacios de la diáspora africana

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Agustín Lao-Montes

2007-01-01

Full Text Available Este artículo desarrolla un argumento teórico y metodológico sobre cómo analizar y transformar la modernidad capitalista a partir de una conceptualización de la diáspora africana como categoría geo-histórica clave que significa, por un lado un proceso de larga duración dentro del cual se constituyen sujetos históricos, expresiones culturales, corrientes intelectuales y movimientos sociales; por otro lado una condición moderna/colonial tanto de opresión (en todas sus dimensiones: culturales, socio-económicas, políticas, epistémicas y existenciales como de agencia histórica y auto-desarrollo de los sujetos de la Africanía moderna; y tercero como un proyecto descolonizador de liberación que se afirma y articula en el accionar de los sujetos, pueblos y movimientos afrodiaspóricos. Eel artículo esboza una genealogía de las diásporas afroamericanas tanto en su pluralidad como en sus vínculos, enfocándose en las diásporas afro-latinas. Como uno de los hitos principales de la perspectiva afrodiaspórica descolonizadora que se elabora en el trabajo, se establece un diálogo político epistémico entre el «feminismo de las mujeres de color» con la teoría y la crítica de la modernidad a partir del concepto de colonialidad del poder

Specialised use of working memory by Portia africana, a spider-eating salticid.

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Cross, Fiona R; Jackson, Robert R

2014-03-01

Using expectancy-violation methods, we investigated the role of working memory in the predatory strategy of Portia africana, a salticid spider from Kenya that preys by preference on other spiders. One of this predator's tactics is to launch opportunistic leaping attacks on to other spiders in their webs. Focussing on this particular tactic, our experiments began with a test spider on a ramp facing a lure (dead prey spider mounted on a cork disc) that could be reached by leaping. After the test spider faced the lure for 30 s, we blocked the test spider's view of the lure by lowering an opaque shutter before the spider leapt. When the shutter was raised 90 s later, either the same lure came into view again (control) or a different lure came into view (experimental: different prey type in same orientation or same prey type in different orientation). We recorded attack frequency (number of test spiders that leapt at the lure) and attack latency (time elapsing between shutter being raised and spiders initiating a leap). Attack latencies in control trials were not significantly different from attack latencies in experimental trials, regardless of whether it was prey type or prey orientation that changed in the experimental trials. However, compared with test spiders in the no-change control trials, significantly fewer test spiders leapt when prey type changed. There was no significant effect on attack frequency when prey orientation changed. These findings suggest that this predator represents prey type independently of prey orientation.

Analyzing Vegetation Change in an Elephant-Impacted Landscape Using the Moving Standard Deviation Index

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Timothy J. Fullman

2014-01-01

Full Text Available Northern Botswana is influenced by various socio-ecological drivers of landscape change. The African elephant (Loxodonta africana is one of the leading sources of landscape shifts in this region. Developing the ability to assess elephant impacts on savanna vegetation is important to promote effective management strategies. The Moving Standard Deviation Index (MSDI applies a standard deviation calculation to remote sensing imagery to assess degradation of vegetation. Used previously for assessing impacts of livestock on rangelands, we evaluate the ability of the MSDI to detect elephant-modified vegetation along the Chobe riverfront in Botswana, a heavily elephant-impacted landscape. At broad scales, MSDI values are positively related to elephant utilization. At finer scales, using data from 257 sites along the riverfront, MSDI values show a consistent negative relationship with intensity of elephant utilization. We suggest that these differences are due to varying effects of elephants across scales. Elephant utilization of vegetation may increase heterogeneity across the landscape, but decrease it within heavily used patches, resulting in the observed MSDI pattern of divergent trends at different scales. While significant, the low explanatory power of the relationship between the MSDI and elephant utilization suggests the MSDI may have limited use for regional monitoring of elephant impacts.

Allometry in dinosaurs and mammals

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Lee, Scott

2015-03-01

The proportions of the leg bones change as the size of an animal becomes larger since the mass of the animal increases at a faster rate than the cross-sectional area of its leg bones. For the case of elastic similarity (in which the longitudinal stress in the legs remains constant in animals of all sizes), the diameter d and length L of the femur should be related as d = A L3/2. For geometric similarity (in which all dimensions are scaled by the same factor), d = A L. For animals with femora longer than 20 cm, we find the power law relationship to be d = A Lb with b = 1.13 +/- 0.06 for extant mammals (the largest mammal being Loxodonta africana with a 1.00-m-long femur) and b = 1.18 +/- 0.02 for dinosaurs (the largest dinosaur being Brachiosaurus brancai with a 2.03-m-long femur). These data show that extinct dinosaurs and extant animals scale in the same basic manner. The large sauropods (with femora twice as long as found in elephants) scale in a manner consistent with extrapolation of the scaling shown by extant mammals. These results argue that extinct dinosaurs moved in a manner very similar to extant mammals.

Stable isotope series from elephant ivory reveal lifetime histories of a true dietary generalist.

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Codron, Jacqueline; Codron, Daryl; Sponheimer, Matt; Kirkman, Kevin; Duffy, Kevin J; Raubenheimer, Erich J; Mélice, Jean-Luc; Grant, Rina; Clauss, Marcus; Lee-Thorp, Julia A

2012-06-22

Longitudinal studies have revealed how variation in resource use within consumer populations can impact their dynamics and functional significance in communities. Here, we investigate multi-decadal diet variations within individuals of a keystone megaherbivore species, the African elephant (Loxodonta africana), using serial stable isotope analysis of tusks from the Kruger National Park, South Africa. These records, representing the longest continuous diet histories documented for any extant species, reveal extensive seasonal and annual variations in isotopic--and hence dietary--niches of individuals, but little variation between them. Lack of niche distinction across individuals contrasts several recent studies, which found relatively high levels of individual niche specialization in various taxa. Our result is consistent with theory that individual mammal herbivores are nutritionally constrained to maintain broad diet niches. Individual diet specialization would also be a costly strategy for large-bodied taxa foraging over wide areas in spatio-temporally heterogeneous environments. High levels of within-individual diet variability occurred within and across seasons, and persisted despite an overall increase in inferred C(4) grass consumption through the twentieth century. We suggest that switching between C(3) browsing and C(4) grazing over extended time scales facilitates elephant survival through environmental change, and could even allow recovery of overused resources.

Chromosome painting among Proboscidea, Hyracoidea and Sirenia: Support for Paenungulata (Afrotheria, Mammalia) but not Tethytheria

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Pardini, A.T.; O'Brien, P. C. M.; Fu, B.; Bonde, R.K.; Elder, F.F.B.; Ferguson-Smith, M. A.; Yang, F.; Robinson, T.J.

2007-01-01

Despite marked improvements in the interpretation of systematic relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea, Sirenia and Proboscidea), remain ambiguous. The combination of a rapid radiation, a deep divergence and an extensive morphological diversification has resulted in a limited phylogenetic signal confounding resolution within this clade both at the morphological and nucleotide levels. Cross-species chromosome painting was used to delineate regions of homology between Loxodonta africana (2n = 56), Procavia capensis (2n=54), Trichechus manatus latirostris (2n = 48) and an outgroup taxon, the aardvark (Orycteropus afer, 2n = 20). Changes specific to each lineage were identified and although the presence of a minimum of 11 synapomorphies confirmed the monophyly of Paenungulata, no change characterizing intrapaenungulate relationships was evident. The reconstruction of an ancestral paenungulate karyotype and the estimation of rates of chromosomal evolution indicate a reduced rate of genomic repatterning following the paenungulate radiation. In comparison to data available for other mammalian taxa, the paenungulate rate of chromosomal evolution is slow to moderate. As a consequence, the absence of a chromosomal character uniting two paenungulates (at the level of resolution characterized in this study) may be due to a reduced rate of chromosomal change relative to the length of time separating successive divergence events. ?? 2007 The Royal Society.

Prenatal passive transfer of maternal immunity in Asian elephants (Elephas maximus).

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Nofs, Sally A; Atmar, Robert L; Keitel, Wendy A; Hanlon, Cathleen; Stanton, Jeffrey J; Tan, Jie; Flanagan, Joseph P; Howard, Lauren; Ling, Paul D

2013-06-15

Asian (Elephas maximus) and African (Loxodonta africana) elephants exhibit characteristics of endotheliochorial placentation, which is common in carnivore species and is associated with modest maternal to fetal transplacental antibody transfer. However, it remains unknown whether the bulk of passive immune transfer in elephants is achieved prenatally or postnatally through ingestion of colostrum, as has been documented for horses, a species whose medical knowledgebase is often extrapolated for elephants. To address this issue, we took advantage of the fact that many zoo elephants are immunized with tetanus toxoid and/or rabies vaccines as part of their routine health care, allowing a comparison of serum antibody levels against these antigens between dams and neonates. Serum samples were collected from 3 newborn Asian elephant calves at birth (before ingestion of colostrum); 2-4 days after birth; and 2-3 months of age. The findings indicate that the newborns had anti-tetanus toxoid and anti-rabies titers that were equivalent to or higher than the titers of their dams from birth to approximately 3 months of age, suggesting that the majority of maternal-to-fetal transfer is transplacental and higher than expected based on the architecture of the Asian elephant placenta. Copyright © 2013 Elsevier B.V. All rights reserved.

Influence of dominance status on adrenal activity and ovarian cyclicity status in captive African elephants.

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Proctor, Christine M; Freeman, Elizabeth W; Brown, Janine L

2010-01-01

The North American African (Loxodonta africana) elephant population is not self-sustaining, in part because of a high rate of abnormal ovarian activity. About 12% of adult females exhibit irregular cycles and 31% do not cycle at all. Our earlier work revealed a relationship between dominance status and ovarian acyclicity, with dominant females being more likely to not cycle normally. One theory is that dominant females may be expending more energy to maintaining peace within the captive herd than for supporting reproduction. The goal of this study was to determine if there was a relationship among dominance status, serum cortisol concentrations, and ovarian acyclicity. We hypothesized that adrenal glucocorticoid activity would be increased in dominant, noncycling elephants as compared with subdominant individuals. Blood samples were collected weekly over a 2-year period in 81 females of known dominance and cyclicity status, and analyzed for cortisol. Based on a path analysis model (Reticular Action Model Or Near Approximation [RAMONA]), noncycling, dominant African elephant females did not have higher mean serum cortisol concentrations, or exhibit more variability (i.e., coefficient of variation, standard deviation) in cortisol secretion. This study suggests that alterations in adrenal activity are not related to dominance status nor contribute directly to acyclicity in captive African elephants.

Analysis of essential oils from Voacanga africana seeds at different hydrodistillation extraction stages: chemical composition, antioxidant activity and antimicrobial activity.

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Liu, Xiong; Yang, Dongliang; Liu, Jiajia; Ren, Na

2015-01-01

In this study, essential oils from Voacanga africana seeds at different extraction stages were investigated. In the chemical composition analysis, 27 compounds representing 86.69-95.03% of the total essential oils were identified and quantified. The main constituents in essential oils were terpenoids, alcohols and fatty acids accounting for 15.03-24.36%, 21.57-34.43% and 33.06-57.37%, respectively. Moreover, the analysis also revealed that essential oils from different extraction stages possessed different chemical compositions. In the antioxidant evaluation, all analysed oils showed similar antioxidant behaviours, and the concentrations of essential oils providing 50% inhibition of DPPH-scavenging activity (IC50) were about 25 mg/mL. In the antimicrobial experiments, essential oils from different extraction stages exhibited different antimicrobial activities. The antimicrobial activity of oils was affected by extraction stages. By controlling extraction stages, it is promising to obtain essential oils with desired antimicrobial activities.

Toxicological parameters of albino rats fed with extruded snacks from Aerial yam (Dioscoria bulbifera) and African breadfruit seed (Treculia africana).

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Olatoye, Kazeem K; Arueya, Gibson L

2018-01-01

In this study, safety of novel food from aerial yam and Treculia africana , underutilized food materials with high-nutritive value and health benefits were investigated. Animal experiment involving the use of thirty (30) male albino rats was conducted for 28 days.Thereafter, rats in all groups were sacrificed and blood samples collected for biochemical analysis and hematological assay. Some vital organs were harvested and used for histological analysis. Biochemical and hematological parameters were not significantly p  ≤ .05 different among the treatment and controls. However there was an increase in monocytes, which is a reflection of immune boosting potential of the novel snack. No significant pathological changes were observed in liver and kidney of rats fed with this snack. Rats showed no signs of toxicity within the study period. These findings suggest that product may be safe and useful as an Immune adjuvant.

Representações da História e cultura Afro-Brasileira e Africana nos documentos escolares de uma escola de Ensino Fundamental do Paraná

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Sandra Aparecida Batista

2017-05-01

Full Text Available Diante da grande diversidade étnico-racial e dos conflitos e tensões em torno das representações da História e Cultura Afro-Brasileira e africana, o objeto de estudo desta pesquisa são as representações que se refletem nos documentos escolares, Projeto Político Pedagógico (PPP, Proposta Pedagógica Curricular (PPC e Plano de Trabalho Docente (PTD que sistematizam a organização didática pedagógica de uma escola do Ensino Fundamental do estado do Paraná. Partimos de algumas indagações que são discutidas ao longo do texto, a saber: o que são representações, conteúdos da disciplina de História isentos ou repletos de representações, e por fim a análise dos documentos escolares e dos respectivos conteúdos da disciplina de História referente às Séries Finais do Ensino Fundamental, considerando que os mesmos são permeados de representações. O estudo aponta que as representações denominadas de hegemônicas, advindas da classe dominante branca com um discurso preconceituoso e estereotipado foram sendo substituídas por representações anti-hegemônicas, que versam sobre o reconhecimento e valorização da História e Cultura Afro-Brasileira e Africana, tendo a Lei 10 639/03 um papel importante neste sentido. Por sua vez, alerta que não se trata de uma perspectiva homogeneizadora e uniformizadora, ou de transição curricular do protagonismo branco e europeu para o negro e africano, mas de uma visão plural, dinâmica e contextualizada da temática.

Plantas de la Diáspora Africana en la botánica americana de la fase Colonial

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Judith Carney

2003-12-01

botany.//Las plantaciones revolucionarias y los intercambios ecológicos que acompañaron la expansión marítima europea después de 1492 son muy apreciados en la actualidad. De igual manera lo son los significados de las nuevas plantas dentro de la sociedad europea en tanto que modificaron preferencias culinarias, la economía y el comercio incluso más allá de las fronteras del viejo continente. El papel del maíz amerindio y de la mandioca en África occidental ha recibido una amplia atención así como el arroz asiático dentro de la región. Pero la literatura sobre el intercambio de alimentos sigue siendo muy escasa en cuanto a la difusión de plantas africanas y a las vías mediante las que dicha dispersión fue posible. Para estudiar este problema es necesario atender al comercio de esclavos y a la forma en la que éstos pudieron establecer preferencias alimentarias en las Américas. Este ensayo examina las plantas de origen africano que se convirtieron en productos esenciales dentro de las economías en la era de las plantaciones esclavistas. Tres centros de domesticación agrícola en el África Subsahariana contribuyeron a la diversidad de recursos que ayudaron a la subsistencia de millones y que fueron llevadas más allá del Atlántico debido al comercio de esclavos. La plantación de dichos productos se llevó a cabo en las Américas gracias a los “jardines botánicos” de los desposeídos: los campos de subsistencia de las plantaciones, jardines, patios y en parcelas agrícolas de las comunidades mulatas. Al llamar la atención sobre la Diáspora africana de plantas se abre la posibilidad de comprender los sistemas de conocimiento africanos. La expresión de dichos sistemas se refleja en las relaciones de poder prevalecientes, en las preferencias de alimentos, la identidad cultural, y las luchas por el proceso de trabajo.Al mostrar las plantas africanas establecidas en América, este trabajo busca corregir las distorsiones en las narrativas del

Fabricación de adoquines para uso en vías peatonales, usando cuesco de palma africana

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Jorge Elías Buzón Ojeda

2010-01-01

Full Text Available Con el fin de mejorar la calidad de vida en sectores vulnerables de la sociedad, las investigaciones actuales han centrado sus esfuerzos en desarrollar no solo técnicas y procesos novedosos de construcción, sino que han reorientado sus esfuerzos en crear materiales de construcción no convencionales, que ayuden a rebajar costos y propicien el de la industria de la construcción. Actualmente las plantas productoras de aceite que usan la palma africana como materia prima enfrentan un grave problema, al no saber qué hacer con el desecho final del proceso de producción del aceite. Este desecho posee características mecánicas interesantes: una alta dureza, alta resistencia al desgaste y bajo peso o poca densidad. Estas características la han sabido aprovechar los cultivadores e industriales, pues en lugar de llevar este excedente a botaderos, lo arrojan sobre las vías internas de las plantaciones como material base o capa de rodadura, mejorando así la movilidad de las mismas. Este artículo presenta los satisfactorios resultados parciales de la investigación, que nos motivan a continuar trabajando en este tema.

Pequeños productores, reestructuración y expansión de la palma africana en Chiapas

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Héctor B. Fletes Ocón

2013-01-01

Full Text Available En el contexto del dinamismo y contradicciones del sector agroalimentario, en la actualidad los pequeños productores son impulsados a emprender una reestructuración de sus prácticas productivas, a través de la plantación de cultivos orientados a biocombustibles, como el de la palma africana. En este artículo se analizan los procesos de reestructuración productiva, promovida por corpora-ciones de distinto origen y por el Estado, y las acciones realizadas por pequeños productores en un municipio con alta marginación, localizado en una región agroexportadora de Chiapas. Se revisan las contradicciones sociales y ambientales de este cambio y sus implicaciones a futuro, en términos del desarrollo agrícola y alimentario nacional. La expansión de este cultivo acentúa las desigualdades sociales, degrada los recursos naturales, utiliza mucha energía fósil, impulsa la concentración de la tierra, debilita los sistemas locales de provisión de alimentos y reduce los márgenes del valor generado en la cadena agroalimentaria para los pequeños productores.

Propuesta metodológica para la gestión formativa socio-cultural profesional en las universidades africanas

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MsC. Moussa Moustapha

2015-10-01

Full Text Available En la actualidad, para un desarrollo económico, social, cultural, político y profesional sustentable en los países subdesarrollados, es imprescindible que sus instituciones de la educación superior, como entidades sociales, tengan sus propios modelos pedagógicos y metodológicos, conforme a las realidades de sus contextos. Ello le permite no solamente jugar su rol social, involucrándose más en el desarrollo y transformación de su contexto, sino encausar una formación de profesionales que trascienden su tiempo, comprometidos, auténticos, flexibles, competitivos y orgullosos de sus tradiciones y costumbres.En el presente trabajo, proponemos una metodología de gestión formativa socio-cultural profesional para las universidades africanas, cuyo objetivo es contextualizar los procesos universitarios africanos. Ella es premisa de una valoración científica de los realidades socio-culturales contextuales, que desde sus raíces humanistas, ancestrales, milenarias y sus riquezas como potencialidades socio-culturales asienten el desarrollo de una identidad y autenticidad formativa profesional y un desarrollo cultural universitaria para el empoderamiento del proceso.

Paz y seguridad humana en África: una visión desde la Unión Africana

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Jerónimo Delgado

2009-11-01

Full Text Available En este artículo se analizan las diferentes iniciativas que ha tenido el continente africano en materia de solución de conflictos y consolidación de la paz desde la perspectiva de la seguridad humana. En la primera parte, se identifican los componentes de la seguridad humana y los factores de inseguridad a los que se exponen los individuos en África, para luego examinar los avances del marco legal de la Unión Africana en la prevención de conflictos con énfasis en la seguridad de los individuos.La segunda parte contiene un estudio de las medidas enmarcadas dentro de la seguridad humana con las que cuentan los estados africanos y la comunidad internacional para la adecuada protección de los individuos, mientras se da un acercamiento entre las partes del conflicto para alcanzar el fin de las hostilidades. Finalmente, se afirma que África reconoce que la seguridad de sus ciudadanos es viable si se entienda que ésta es una responsabilidad compartida por todo el continente, en donde el individuo juega un papel central.

Evaluation of Demographics and Social Life Events of Asian (Elephas maximus and African Elephants (Loxodonta africana in North American Zoos.

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Natalia A Prado-Oviedo

Full Text Available This study quantified social life events hypothesized to affect the welfare of zoo African and Asian elephants, focusing on animals that were part of a large multi-disciplinary, multi-institutional elephant welfare study in North America. Age was calculated based on recorded birth dates and an age-based account of life event data for each elephant was compiled. These event histories included facility transfers, births and deaths of offspring, and births and deaths of non-offspring herd mates. Each event was evaluated as a total number of events per elephant, lifetime rate of event exposure, and age at first event exposure. These were then compared across three categories: species (African vs. Asian; sex (male vs. female; and origin (imported vs. captive-born. Mean age distributions differed (p<0.05 between the categories: African elephants were 6 years younger than Asian elephants, males were 12 years younger than females, and captive-born elephants were 20 years younger than imported elephants. Overall, the number of transfers ranged from 0 to 10, with a 33% higher age-adjusted transfer rate for imported African than imported Asian elephants, and 37% lower rate for imported females than males (p<0.05. Other differences (p<0.05 included a 96% higher rate of offspring births for captive-born females than those imported from range countries, a 159% higher rate of birthing event exposures for captive-born males than for their imported counterparts, and Asian elephant females being 4 years younger than African females when they produced their first calf. In summarizing demographic and social life events of elephants in North American zoos, we found both qualitative and quantitative differences in the early lives of imported versus captive-born elephants that could have long-term welfare implications.

Evaluación de Varios Insecticidas para el Control del Cephaloleiaspcerca avagelineataPic, Plaga de la Palma Africana

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Urueta Sandino Eduardo

1974-04-01

Full Text Available Resumen. Se efectuaron varios ensayos para determinar el efecto de carbofuran 1.0, 1.5 y 2. 0 kg I. A./ha; carbaril 1.5 y 2. 0 kg I. A. /ha; lindano 1.0 y 1.5 kg I. A. /ha; diazinon 0.5 lt I. A./ha; dicrotofos 0. 5 lt I. A. /ha; fosfamidon 0.6 lt. I. A/ha; y fention 0.5 lt I. A./ha, sobre adultos y larvas de Cephaloleiasp. cerca avagelineataPic., una plaga de la palma africana en Colombia. Todos los insecticidas fueron efectivos para controlar larvas de Cephaloleiasp. en cogollos, hasta por periodos de más de 30 días. El carbofuran 2.0 kg I. A./ha carbaril 2.0 kg l . A./ha y lindano 1. 5 kg I.A. /hafueron los productos más eficientes para controlar adultos de Cephaloleia. sp. protegiendo por 15 días las hojas más jóvenes. Dicrotofos 0.5 lt I. A./ha; diazinon0.5 lt l. A./ha; fention 0.5 itI. A./ha y fosfamidon 0.6 lt I. A/ha, aparentemente no fueron efectivos para controlar las formas adultas de Cephaloleiasp. Ninguno de los insecticidas fue fitotóxico para la palma africana. /Abstract. Several tests were carried out to determine the effectiveness of carbofuran 1. 0, 1.5 and 2.0 kg A.I./ha; carbaryl 1.5, 2.0 kg. A.I./ha; lindane 1.0, 1.5 kg. A.I./ha; phosphamidon 0.6 lt. A.I./ha; fenthion 0.5 lt. A.I./ha; dicrotophos 0.5 lt. A.I /ha; diazinon 0.5 lt. A.I./ha on larvae and adults of Cephaloleia. sp. near vagelineata Pic a Chrysomelidae that affects young oil palm (Elaeisguineensis leaves in Colombia. All of these insecticides controlled well Cepbaloleia sp. larvae for periods over a month. carbofuran 2 kg. A.I./ha; carbaryl 2kg. A.I./ha and lindane 1.5 kg. A. I./ha gave the best control of Cephaloleia. sp. adults, protecting young oil palm leaves up to 15 days. Dicrotophos 0.5 lts. A.I./ha; fenthion 0.5 lt. A. I./ha; phosphamidon 0.6 lt. A.I./ha; diazinon 0.5 lt. A.I./ha; apparently were not effective to control adults of Cephaloleia sp. None of the insecticides tested showed to be phytotoxic to the oil palm.

Matrices coloniales y diásporas africanas: Hacia una investigación de las culturas negra y mulata en la Nueva Granada

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Rafael Antonio Díaz Díaz

2003-12-01

estará definido por la teoría de la cultura colonial. Posteriormente, me concentraré en el campo de las etapas transatlánticas como una escena fluida para la Diáspora africana y trataré de recuperar la dimensión africana de ésta.

Complexity, adaptations and variations in the secondary insemination system of female Dermanyssina mites (Acari: Anactinothrichida: Gamasida): the case of Afrocypholaelaps africana.

Science.gov (United States)

Di Palma, A; Seeman, O D; Alberti, G

2017-07-01

Gamasine mites, mainly of the taxon Dermanyssina, possess a secondarily evolved insemination system (sperm access system), of which there are two, generally recognized, structurally different types, the laelapid- and the phytoseiid-type. The ultrastructure of the female sperm access system in Afrocypholaelaps africana is described. It consists of paired insemination pores, opening between the bases of legs three and four, and paired cuticle-lined tubules that converge into a large, sack-like spermatheca, remarkably cuticle-lined as well. The entire spermatheca and part of the tubules are embedded in a peculiar syncytial tissue where numerous sperm cells are present. The general organization of this insemination system is of the laelapid-type. However, it presents striking structural differences, compared with the systems described in Varroa destructor and Hattena cometis, the other gamasine mites having a laelapid-type system studied ultrastructurally until now. The functional morphology, complexity and variations of the sperm access system in Dermanyssina are discussed and correlated with the evolutionary biology of the group.

Autoras africanas: A favor de las mujeres=African authors: In favor of women

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Socorro Suárez Lafuente

2017-06-01

Full Text Available Resumen: La cultura occidental produce binomios de poder fuertemente inscritos en el lenguaje y el imaginario colectivo. Las subversiones aparecen primero en la zona dominante, como el feminismo, que se extiende, posteriormente, a otros feminismos, igualmente lógicos y reivindicativos, pero con menos capacidad de visibilización en un mundo globalizado. Las mujeres de grupos minorizados que han conseguido acceder a la educación han levantado sus voces y utilizado su potencial creativo a favor de las silenciadas de su cultura, a las que no alcanzaban el feminismo blanco occidental. Amma Darko, Bessie Head y Chimamanda Ngozi Adichie son algunos de los nombres que encabezan un movimiento africano feminista, que prioriza la libertad individual de las mujeres y les hace sentirse orgullosas de ser africanas.   Abstract Western culture produces binaries of power that are deeply inscribed both in language and in the collective imaginarium. Subversions tend to appear in the more affluent class, as is the case with feminism, which later extend to other feminisms, equally important and vindicatory, but with fewer opportunities to become visible within a globalized world. Many women from minoritized groups have had access to education, have been able to use their creative force and have become the voice of many silent women who were not included in the successive waves of Western feminisms. Amma Darko, Bessie Head and Chimamanda Ngozi Adichie are but a few names at the forefront of African feminism, a movement that fights for the individual rights of women and makes them feel proud of their Africanism.

Avaliação nutricional da grama-estrela cv. Africana para vacas leiteiras em condições de pastejo Nutritional analysis of stargrass cv. Africana for dairy cattle under rotational grazing

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Maurício Gomes Favoreto

2008-02-01

Full Text Available Objetivou-se avaliar nutricionalmente a grama-estrela (Cynodon nlemfuensis cv. Africana utilizada sob pastejo rotacionado por vacas leiteiras. Dez vacas mestiças foram manejadas em 2 ha de grama-estrela e divididas em 11 piquetes/ha. O período de pastejo foi de três dias e os 30 subseqüentes foram destinados à recuperação da pastagem. Durante o período experimental, os animais foram ordenhados duas vezes ao dia e receberam suplementação com 2 kg de concentrado. Amostras representativas do pasto ingeridas (extrusa foram colhidas para determinação de sua composição nutricional. O consumo de matéria seca (MS pelos animais foi estimado utilizando-se cromo e a MS indigestível como indicadores externo e interno. O desempenho individual das vacas foi avaliado pela produção de leite diária e pela pesagem dos animais. A dinâmica da matéria alimentar foi estimada com base nas técnicas in vitro gravimétricas, de produção cumulativa de gases da fermentação microbiana e da estimativa da cinética de passagem das fases sólida e líquida. A quantidade de energia líquida total (ELt, em MJ/dia, atendeu à demanda energética exigida pelos animais. Os valores de proteína metabolizável (PM preditos corresponderam ao suprimento de 91% da PM exigida por esses animais. As predições das exigências em macrominerais atenderam apenas 75% do Ca exigido, mas atenderam às exigências dos demais macrominerais. A grama-estrela atende à demanda energética nutricional de mantença e produção de 11,7 kg de leite por dia. Nas circunstâncias estudadas, é necessário suplementar nutrientes que complementem a PM e Ca não atendidos completamente. O teor e as características cinéticas da fibra não causam repleção ruminal e restrição sobre o consumo de vacas leiteiras em pastejo.An nutritional analysis of stargrass cv. Africana fed dairy cattle under rotational grazing was evaluated in this research. Ten Holstein-Zebu crossbred cows were

The ties that bind: genetic relatedness predicts the fission and fusion of social groups in wild African elephants.

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Archie, Elizabeth A; Moss, Cynthia J; Alberts, Susan C

2006-03-07

Many social animals live in stable groups. In contrast, African savannah elephants (Loxodonta africana) live in unusually fluid, fission-fusion societies. That is, 'core' social groups are composed of predictable sets of individuals; however, over the course of hours or days, these groups may temporarily divide and reunite, or they may fuse with other social groups to form much larger social units. Here, we test the hypothesis that genetic relatedness predicts patterns of group fission and fusion among wild, female African elephants. Our study of a single Kenyan population spans 236 individuals in 45 core social groups, genotyped at 11 microsatellite and one mitochondrial DNA (mtDNA) locus. We found that genetic relatedness predicted group fission; adult females remained with their first order maternal relatives when core groups fissioned temporarily. Relatedness also predicted temporary fusion between social groups; core groups were more likely to fuse with each other when the oldest females in each group were genetic relatives. Groups that shared mtDNA haplotypes were also significantly more likely to fuse than groups that did not share mtDNA. Our results suggest that associations between core social groups persist for decades after the original maternal kin have died. We discuss these results in the context of kin selection and its possible role in the evolution of elephant sociality.

Large herbivores that strive mightily but eat and drink as friends.

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de Boer, W F; Prins, H H T

1990-02-01

Grazing in patches of Cynodon dactylon and of Sporobolus spicatus by four large herbivores, and the interaction between these sedentary herbivores was studied in Lake Manyara National Park, northern Tanzania. The herbivores were the African buffalo, Syncerus caffer; the African elephan, Loxodonta africana; the Burchell's zebra, Equus burchelli; and the wildebeest, Connochaetus taurinus. Four different hypotheses of the interactions between the herbivores were tested, viz., increased predator detection/protection through association of species, facilitation of the food intake through the influence of other species, use by other species of the food manipulation strategy of buffalo, and interspecific competition for food. On the level of a single day, zebra and wildebeest were symbiotic, which could have been caused by an increased chance of predator detection. A similar association between buffalo and wildebeest or zebra was also detected on C. dactylon grasslands. There was no indication of facilitation between any of the herbivores. Buffalo had a despotic relationship with elephant, that is the elephant's consumption was lowered when buffalo had visited a patch prior to their arrival. When elephant and buffalo arrived at the same time there appeared to be scramble competition between them.Habitat overlap was calculated for four pairs of species. In conjunction with the analyses of the patch visits, it was concluded that a small overlap was associated with interspecific competition and a large habitat overlap was associated with symbiosis.

Poaching and human encroachment reverse recovery of African savannah elephants in south-east Angola despite 14 years of peace

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Chase, Michael J.; Griffin, Curtice R.

2018-01-01

With populations of African savannah elephants (Loxodonta africana) declining across the continent, assessing the status of individual elephant populations is important for conservation. Angola’s elephant population represents a key linkage between the larger populations of Namibia and Botswana. Elephants in Angola were decimated during the 1975–2002 Angolan civil war, but a 2005 survey showed that populations were recolonizing former habitats. Between 2005 and 2015, no research was permitted on elephants in Angola, but elsewhere in Africa many elephant populations experienced a poaching crisis. In 2015, we were able to resume elephant research in Angola. We used aerial surveys and satellite monitoring of collared elephants to determine the current status of elephant populations in Angola and to learn how human populations may be affecting elephant habitat usage. The aerial survey revealed a population of 3,395 ± SE of 797 elephants, but populations had declined 21% from the 2005 estimate. The high number of carcasses observed on the survey suggests that populations may have increased after the 2005 survey but were declining rapidly as of 2015. Satellite-collared elephants avoided areas elephants from preferred habitats near rivers. Taken together, these results suggest that Angola’s elephant population is experiencing intense poaching and may be losing habitat to human settlements. Without action to conserve their populations, Angola’s elephants face an uncertain future. PMID:29538387

Migración africana y formación social en las Américas, 1500-2000

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Moya, José C.

2012-08-01

Full Text Available Around 11 million Africans reached the New World between 1500 and 1866 in what constitutes the first massive transoceanic migration in the history of humanity. This article approaches that movement from the perspective of the history of migrations and socio-racial formations in the Americas. The first part establishes the origins, timing, and geographic distribution of the arrivals using a database with information on some 35,000 slave ship voyages. We go on to analyze how this determined the demographic impact, socio-economic development, African cultural presence, adaptation and acculturation strategies, and the construction of racial taxonomies and identities in the receiving regions.

Unos 11 millones de africanos llegaron al Nuevo Mundo entre 1500 y 1866 en lo que constituye la primera migración masiva transoceánica en la historia de la humanidad. Este artículo estudia ese movimiento desde la perspectiva de la historia de las migraciones y formaciones socio-raciales en las Américas. La primera parte establece el origen, ritmo temporal y distribución geográfica de las llegadas empleando una base de datos que contiene información sobre unos 35.000 viajes de barcos negreros. Sobre esta base, se analiza el impacto demográfico, el desarrollo socioeconómico, la presencia cultural africana, las estrategias de adaptación y aculturación, y la construcción de taxonomías e identidades raciales en las regiones receptoras.

A cidade africana contemporânea de origem portuguesa: São Tomé pré e pós-independência The contemporary African city of Portuguese origin: Sao Tome pre and post-independence

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Teresa Madeira da Silva

2012-12-01

Full Text Available A cidade de São Tomé foi território português desde as primeiras ocupações até 1975 (data de sua independência,tendo, nesse tempo, crescido segundo os princípios do urbanismo de origem portuguesa. Para além da cidade planeada e consolidada, construída no período de ocupação colonial, a cidade desenvolveu, sobretudo no período pós-independência, um outro tipo de estrutura sem planeamento. À semelhança de outras cidades africanas de origem portuguesa, essa nova estrutura localiza-se na periferia do centro urbano. Este artigo apresenta dois argumentos. O primeiro considera que a cidade de São Tomé apresenta uma estrutura dual, tal como outras cidades africanas: uma zona central planeada, construída no período da ocupação colonial (pré-independência, e outra, periurbana, constituída essencialmente por habitações resultantes da expansão habitacional do centro urbano e com certas características semirrurais: vivendas associadas a espaços de produção agrícola familiar. O segundo argumento refere que tanto a estrutura central planeada, desenvolvida no período colonial, como a estrutura periférica não planeada, desenvolvida posteriormente,têm, na sua origem e desenvolvimento, a procura de relações com o território e, tanto numa como noutra,reconhecem-se estruturas urbanas adaptadas às condições locais.

Caracterización estructural por adsorción y difracción de rayos X de monolitos de carbón activado a partir de cáscara de coco y cuesco de palma africana

OpenAIRE

Vargas Delgadillo, Diana; Giraldo-Gutiérrez, Liliana; Moreno-Piraján, Juan

2009-01-01

Se prepararon monolitos de carbón activado tipo disco utilizando como precursores por separado cáscara de coco y cuesco de palma africana mediante la activación química con ácido fosfórico, utilizando diferentes concentraciones, sin el uso de ningún aglomerante. Se presentan el rendimiento del proceso, así como los parámetros estructurales determinados por adsorción de N2 a 77 K y CO2 a 273 K, y se comparan con algunos parámetros cristalográficos determinados por difracción de rayos X. Se obt...

Geografías urbanas: representación e identidad en la literatura africana en español

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M’bare N’gom

2012-12-01

Full Text Available Este trabajo estudia las representaciones de las geografías urbanas y sus problemáticas en la literatura africana de expresión castellana. Para tal efecto propone la representación de las realidades urbanas como espacios de experiencias de vida heterogéneas, ya sean culturales, políticas o de renegociación de identidad. Igualmente examina cómo esa geografía urbana se configura como espacio que se presta a la articulación de una multitud de discursos y reinterpretaciones de la realidad urbana y urbanística, que obligan en este caso al sujeto migrante africano a embarcarse en un proceso de reterritorialización desde la transterritorialidad del desplazamiento, como estrategia de supervivencia en ese espacio ajeno y dislocado que es la ciudad.This study explores the representations of urban geography and its problematic in African literature in Spanish. It intends to examinate the representation of urban realities as spaces of heterogeneous experiences, be they cultural, political, or renegociation of identity. Along those lines, this study will discuss how urban geography becomes a space that allows a multitude of negociations, as well as the articulation of a variety of discourses and reinterpretations of urban and urbanistic reality that oblige the African migrant subject, in this case, to engage in a process of reterritorialization from the transterritoriality of displacement, as a strategy for survival in an alien and dislocated space such as the City.

Producción de biomasa y costos de producción de pastos estrella africana (Cynodon nlemfuensis, kikuyo (Kikuyuocloa clandestina y ryegrass perenne (Lolium perenne en lecherías de Costa Rica

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Luis Villalobos

2013-01-01

Full Text Available Se evaluó la producción de biomasa, los costos de producción y el costo del kilogramo de materia seca en los pastos kikuyo (Kikuyuocloa clandestina, ryegrass perenne (Lolium perenne y estrella africana (Cynodon nlemfuensis, a lo largo de un año, en 8 fincas comerciales ubicadas en las provincias de Cartago (2, San José (2 y Alajuela (4. La producción de biomasa promedio por ciclo para los 3 pastos fue de 3395 kg.ha-1 MS; la producción anual se ve influenciada por los días de recuperación de cada especie, mostrando valores de 40 170, 38 731 y 28 995 kg.ha-1 de MS para los pastos estrella africana, kikuyo y ryegrass perenne, respectivamente. La producción de biomasa varía durante el año y en las épocas de mayor producción de esa biomasa, los animales tienen un menor aprovechamiento de la pastura en términos porcentuales, debido a que la carga animal, los períodos de permanencia y las áreas de pastoreo no se ajustan a la disponibilidad de forraje. Los costos anuales de mano de obra, insumos y tierra promedio fueron de 72.433, 505.515 y 18.760 colones.ha-1, respectiva- mente; siendo los insumos el rubro con un peso relativo mayor en la estructura de costos de las fincas en pastoreo. Los costos del kg de MS producido y consumido, para los 3 pastos evaluados, fueron de 16,6 y 44,4 colones respectivamente, siendo el aprovechamiento que los animales hacen de las pasturas el determinante del costo del material consumido. Las fincas con mayor inversión anual en pasturas, mostraron un mayor retorno en kg.ha-1 leche.

Elephant population growth in Kruger National Park, South Africa, under a landscape management approach

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Sam M. Ferreira

2017-08-01

Full Text Available South African National Parks (SANParks manage landscapes rather than numbers of elephants (Loxodonta africana to mitigate the effects that elephants may have on biodiversity, tourism and stakeholder conservation values associated with protected areas. This management philosophy imposes spatial variability of critical resources on elephants. Restoration of such ecological processes through less intensive management predicts a reduction in population growth rates from the eras of intensive management. We collated aerial survey data since 1995 and conducted an aerial total count using a helicopter observation platform during 2015. A minimum of 17 086 elephants were resident in the Kruger National Park (KNP in 2015, growing at 4.2% per annum over the last generation of elephants (i.e. 12 years, compared to 6.5% annual population growth noted during the intensive management era ending in 1994. This may come from responses of elephants to density and environmental factors manifested through reduced birth rates and increased mortality rates. Authorities should continue to evaluate the demographic responses of elephants to landscape scale interventions directed at restoring the limitation of spatial variance in resource distribution on elephant spatiotemporal dynamics and the consequences that may have for other conservation values. Conservation implications: Conservation managers should continue with surveying elephants in a way that allows the extraction of key variables. Such variables should focus on measures that reflect on how theory predicts elephants should respond to management interventions.

HONGOS MICORRÍCICO-ARBUSCULARES EN LA PRODUCCIÓN DE VIOLETA AFRICANA EN UN SISTEMA DE MANEJO TRADICIONAL

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Ramón Zulueta-Rodríguez

2013-01-01

Full Text Available Se determinó el efecto de la inoculación de violeta africana ( Saintpaulia ionantha Wendl. con hongos micorrícico-arbusculares (HMA en un vivero comercial bajo el sistema de cultivo del productor. Se probaron dos presentaciones del inóculo, raíces frescas (IT e inoculante encapsulado en perlas de alginato de calcio (IE. Los tratamientos establecidos fueron plantas inoculadas con cada uno de los inóculos (IT e IE, plantas fertilizadas sin inocular (F, plantas inoculadas + fertilizante (IT+F e IE+F y plantas testigo (T. Las variables evaluadas 90 y 180 días después de la inoculación (DDI fueron área foliar, número de hojas, de botones florales y de flores, así como la longitud de raíz colonizada, peso seco de pecíolos, hojas y raíces al final del experimento (180 DDI. El análisis estadístico indicó diferencias altamente significativas entre los tratamientos a los 90 DDI para área foliar, número de botones florales y de flores (ANOVA, P ≤ 0.01, respuesta que prevaleció hasta los 180 DDI con respecto a las plantas testigo (ANOVA, P ≤ 0.01. En general, la interacción de los HMA con el fertilizante promovió una floración prematura, lo cual indica que el uso de estos microorganismos puede considerarse una alterna - tiva biotecnológica factible de incorporar en estos sistemas de producción.

BREADFRUIT (Treculia africana MARKETING ACTIVITIES AND RETURNS IN AHIAZU MBAISE LOCAL GOVERNMENT AREA, OF IMO STATE, NIGERIA

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Ogbonna Christopher EMEROLE

2013-12-01

Full Text Available This study on marketing of breadfruits (Treculia africana and returns was done in Ahiazu Mbaise local Government area of Imo State, Nigeria. The specific objectives of the study were to describe socio-economic characteristics of respondents (sellers and buyers of African breadfruit; identify value-chain activities available in processing and its storage in compliance with consumers’ order and preferences; determine factors influencing decision to supply African breadfruit; and constraints with its post-harvest management in the study area. Three-stage random sampling technique was used in selecting locations and respondents through which eighty (80 farm households who gather/harvest, process and sell breadfruits were selected and interviewed with structured questionnaire. Data collected were analyzed using descriptive statistics, and probit regression model. Result revealed that 65.80% of the respondents were females and 81.20% of them were married with mean household size of 9 members. Their literacy level was high as 97.6% of them had at least primary education. Predominant marketing activities were fruit gathering/harvesting, processing, storage and packaging, transportation, and sales. Socio-economic factors of gender, household size, income, level of education, years of farming experience and labour significantly influenced supply of breadfruits to consumers with challenges of seasonal scarcity, and tedious methods of processing deterring the enterprise in the area. We recommended provision of credit support to enable fruit gatherers purchase and use shelling machines and good storage facilities to smooth any fluctuations in supplies during off-seasons and help fight overdependence of households on roots and tubers.

Applying network theory to animal movements to identify properties of landscape space use.

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Bastille-Rousseau, Guillaume; Douglas-Hamilton, Iain; Blake, Stephen; Northrup, Joseph M; Wittemyer, George

2018-04-01

Network (graph) theory is a popular analytical framework to characterize the structure and dynamics among discrete objects and is particularly effective at identifying critical hubs and patterns of connectivity. The identification of such attributes is a fundamental objective of animal movement research, yet network theory has rarely been applied directly to animal relocation data. We develop an approach that allows the analysis of movement data using network theory by defining occupied pixels as nodes and connection among these pixels as edges. We first quantify node-level (local) metrics and graph-level (system) metrics on simulated movement trajectories to assess the ability of these metrics to pull out known properties in movement paths. We then apply our framework to empirical data from African elephants (Loxodonta africana), giant Galapagos tortoises (Chelonoidis spp.), and mule deer (Odocoileous hemionus). Our results indicate that certain node-level metrics, namely degree, weight, and betweenness, perform well in capturing local patterns of space use, such as the definition of core areas and paths used for inter-patch movement. These metrics were generally applicable across data sets, indicating their robustness to assumptions structuring analysis or strategies of movement. Other metrics capture local patterns effectively, but were sensitive to specified graph properties, indicating case specific applications. Our analysis indicates that graph-level metrics are unlikely to outperform other approaches for the categorization of general movement strategies (central place foraging, migration, nomadism). By identifying critical nodes, our approach provides a robust quantitative framework to identify local properties of space use that can be used to evaluate the effect of the loss of specific nodes on range wide connectivity. Our network approach is intuitive, and can be implemented across imperfectly sampled or large-scale data sets efficiently, providing a

Relações comerciais e diplomáticas Anglo-africanas durante a expedição ao Níger de 1854

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Alexsander Lemos de Almeida Gebara

2016-08-01

Full Text Available Resumo O artigo procura compreender a expedição britânica nos rios Niger e Benue em 1854 num contexto de transformação nas relações políticas e econômicas da Grã Bretanha com o interior da África Ocidental. Tal empreendimento ficou marcado pela ausência de mortes por febres tropicais e deixou vários registros, dentre eles relatos de viagem e a correspondência entre seus agentes e o Foreign Office e o Colonial Office que compõe o corpo de fontes deste artigo. Especial atenção é dedicada aos termos e formas das trocas comerciais realizadas com os africanos diretamente ao longo da viagem e às condições nas quais estes relacionamentos foram estabelecidos. Assim, procura-se por um lado, compreender a expedição como parte de um de um processo de ampliação da presença europeia no interior e, por outro lado, refletir sobre as estratégias africanas em diálogo com as transformações econômicas na bacia Atlântica em meados do século XIX.

CARBÓN ACTIVADO: EFECTO DEL LAVADO CON ÁCIDO SULFÚRICO DEL PRECURSOR LIGNOCELULÓSICO, CUESCO DE PALMA AFRICANA, SOBRE LOS PROCESOS DE CARBONIZACIÓN Y ACTIVACIÓN.

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Luisa Fernanda Navarrete

2008-03-01

Full Text Available Se realizan lavados controlados durante diferentes periodos de tiempo, 6 y 12 horas, con soluciones diluidas de ácido sulfúrico, 2, 5 y 10%, sobre el precursor lignocelulósico cuesco de palma africana, consiguiendo reducir en más del 50% el contenido de cenizas de dicho material, en las que los componentes inorgánicos, principalmente elementos como hierro y aluminio, influyen notablemente en lareacción de gasificación con CO2 durante la activación física.Se determinan las entalpías de inmersión en las muestras con mayor grado de activación con resultados que se encuentran entre el 2 y 10 J.g-1, y se comparan con los obtenidos para carbones activados resultantes de lavar el material de partida con agua en los mismos períodos de tiempo.

Estimating variation in stomatal frequency at intra-individual, intra-site, and inter-taxonomic levels in populations of the Leonardoxa africana (Fabaceae) complex over environmental gradients in Cameroon

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Finsinger, Walter; Dos Santos, Thibaut; McKey, Doyle

2013-07-01

Variation of stomatal frequency (stomatal density and stomatal index) includes genetically-based, potentially-adaptive variation, and variation due to phenotypic plasticity, the degree of which may be fundamental to the ability to maintain high water-use efficiency and thus to deal with environmental change. We analysed stomatal frequency and morphology (pore length, pore width) in leaves from several individuals from nine populations of four sub-species of the Leonardoxa africana complex. The dataset represents a hierarchical sampling wherein factors are nested within each level (leaves in individuals, individuals in sites, etc.), allowing estimation of the contribution of different levels to overall variation, using variance-component analysis. SI showed significant variation among sites ("site" is largely confounded with "sub-species"), being highest in the sub-species localized in the highest-elevation site. However, most of the observed variance was accounted for at intra-site and intra-individual levels. This variance could reflect great phenotypic plasticity, presumably in response to highly local variation in micro-environmental conditions.

Toward sustainable harvesting of Africa's largest medicinal plant ...

African Journals Online (AJOL)

Global demand for treating prostate disorders with Prunus africana bark extract has made P. africana Africa's largest medicinal plant export. Unsustainable harvesting practices can lead to local extirpations of this multipurpose tree. Survey research targeting P. africana harvesters in a Tanzania forest reserve revealed that ...

Identification of high-efficiency 3′GG gRNA motifs in indexed FASTA files with ngg2

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Elisha D. Roberson

2015-11-01

Full Text Available CRISPR/Cas9 is emerging as one of the most-used methods of genome modification in organisms ranging from bacteria to human cells. However, the efficiency of editing varies tremendously site-to-site. A recent report identified a novel motif, called the 3′GG motif, which substantially increases the efficiency of editing at all sites tested in C. elegans. Furthermore, they highlighted that previously published gRNAs with high editing efficiency also had this motif. I designed a Python command-line tool, ngg2, to identify 3′GG gRNA sites from indexed FASTA files. As a proof-of-concept, I screened for these motifs in six model genomes: Saccharomyces cerevisiae, Caenorhabditis elegans, Drosophila melanogaster, Danio rerio, Mus musculus, and Homo sapiens. I also scanned the genomes of pig (Sus scrofa and African elephant (Loxodonta africana to demonstrate the utility in non-model organisms. I identified more than 60 million single match 3′GG motifs in these genomes. Greater than 61% of all protein coding genes in the reference genomes had at least one unique 3′GG gRNA site overlapping an exon. In particular, more than 96% of mouse and 93% of human protein coding genes have at least one unique, overlapping 3′GG gRNA. These identified sites can be used as a starting point in gRNA selection, and the ngg2 tool provides an important ability to identify 3′GG editing sites in any species with an available genome sequence.

Skeletal pathology and variable anatomy in elephant feet assessed using computed tomography

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Sophie Regnault

2017-01-01

Full Text Available Foot problems are a major cause of morbidity and mortality in elephants, but are underreported due to difficulties in diagnosis, particularly of conditions affecting the bones and internal structures. Here we evaluate post-mortem computer tomographic (CT scans of 52 feet from 21 elephants (seven African Loxodonta africana and 14 Asian Elephas maximus, describing both pathology and variant anatomy (including the appearance of phalangeal and sesamoid bones that could be mistaken for disease. We found all the elephants in our study to have pathology of some type in at least one foot. The most common pathological changes observed were bone remodelling, enthesopathy, osseous cyst-like lesions, and osteoarthritis, with soft tissue mineralisation, osteitis, infectious osteoarthriti, subluxation, fracture and enostoses observed less frequently. Most feet had multiple categories of pathological change (81% with two or more diagnoses, versus 10% with a single diagnosis, and 9% without significant pathology. Much of the pathological change was focused over the middle/lateral digits, which bear most weight and experience high peak pressures during walking. We found remodelling and osteoarthritis to be correlated with increasing age, more enthesopathy in Asian elephants, and more cyst-like lesions in females. We also observed multipartite, missing and misshapen phalanges as common and apparently incidental findings. The proximal (paired sesamoids can appear fused or absent, and the predigits (radial/tibial sesamoids can be variably ossified, though are significantly more ossified in Asian elephants. Our study reinforces the need for regular examination and radiography of elephant feet to monitor for pathology and as a tool for improving welfare.

When elephants fall asleep: A literature review on elephant rest with case studies on elephant falling bouts, and practical solutions for zoo elephants.

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Schiffmann, Christian; Hoby, Stefan; Wenker, Christian; Hård, Therese; Scholz, Robert; Clauss, Marcus; Hatt, Jean-Michel

2018-05-01

Little attention has been paid to the resting and sleeping behavior of zoo elephants so far. An important concern is when elephants avoid lying down, due to degenerative joint and foot disease, social structure, or stressful environmental changes. Inability or unwillingness to lie down for resting is an important welfare issue, as it may impair sleep. We emphasize the importance of satisfying rest in elephants by reviewing the literature on resting behavior in elephants (Loxodonta africana and Elephas maximus) as well as the documentation of four cases from European zoos and our own direct observations in a zoo group of four female African elephants during 12 entire days. The common denominator in the case reports is the occurrence of a falling bout out of a standing position subsequently to a cessation of lying rest for different periods of time. Although well-known in horses as "episodic collapse" or "excessive drowsiness," this syndrome has not been described in elephants before. To enable its detection, we recommend nocturnal video monitoring for elephant-keeping institutions. The literature evaluation as well as own observational data suggest an inverse relationship between lying rest and standing rest. Preventative measures consist of enclosure modifications that facilitate lying rest (e.g., sand hills) or standing rest in a leaning position as a substitute. Anecdotal observations suggest that the provision of appropriate horizontal environmental structures may encourage safe, sleep-conducive standing rest. We provide drawings on how to install such structures. Effects of providing such structures should be evaluated in the future. © 2018 Wiley Periodicals, Inc.

Complex vibratory patterns in an elephant larynx.

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Herbst, Christian T; Svec, Jan G; Lohscheller, Jörg; Frey, Roland; Gumpenberger, Michaela; Stoeger, Angela S; Fitch, W Tecumseh

2013-11-01

Elephants' low-frequency vocalizations are produced by flow-induced self-sustaining oscillations of laryngeal tissue. To date, little is known in detail about the vibratory phenomena in the elephant larynx. Here, we provide a first descriptive report of the complex oscillatory features found in the excised larynx of a 25 year old female African elephant (Loxodonta africana), the largest animal sound generator ever studied experimentally. Sound production was documented with high-speed video, acoustic measurements, air flow and sound pressure level recordings. The anatomy of the larynx was studied with computed tomography (CT) and dissections. Elephant CT vocal anatomy data were further compared with the anatomy of an adult human male. We observed numerous unusual phenomena, not typically reported in human vocal fold vibrations. Phase delays along both the inferior-superior and anterior-posterior (A-P) dimension were commonly observed, as well as transverse travelling wave patterns along the A-P dimension, previously not documented in the literature. Acoustic energy was mainly created during the instant of glottal opening. The vestibular folds, when adducted, participated in tissue vibration, effectively increasing the generated sound pressure level by 12 dB. The complexity of the observed phenomena is partly attributed to the distinct laryngeal anatomy of the elephant larynx, which is not simply a large-scale version of its human counterpart. Travelling waves may be facilitated by low fundamental frequencies and increased vocal fold tension. A travelling wave model is proposed, to account for three types of phenomena: A-P travelling waves, 'conventional' standing wave patterns, and irregular vocal fold vibration.

Vertical Transmission of Social Roles Drives Resilience to Poaching in Elephant Networks.

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Goldenberg, Shifra Z; Douglas-Hamilton, Iain; Wittemyer, George

2016-01-11

Network resilience to perturbation is fundamental to functionality in systems ranging from synthetic communication networks to evolved social organization [1]. While theoretical work offers insight into causes of network robustness, examination of natural networks can identify evolved mechanisms of resilience and how they are related to the selective pressures driving structure. Female African elephants (Loxodonta africana) exhibit complex social networks with node heterogeneity in which older individuals serve as connectivity hubs [2, 3]. Recent ivory poaching targeting older elephants in a well-studied population has mirrored the targeted removal of highly connected nodes in the theoretical literature that leads to structural collapse [4, 5]. Here we tested the response of this natural network to selective knockouts. We find that the hierarchical network topology characteristic of elephant societies was highly conserved across the 16-year study despite ∼70% turnover in individual composition of the population. At a population level, the oldest available individuals persisted to fill socially central positions in the network. For analyses using known mother-daughter pairs, social positions of daughters during the disrupted period were predicted by those of their mothers in years prior, were unrelated to individual histories of family mortality, and were actively built. As such, daughters replicated the social network roles of their mothers, driving the observed network resilience. Our study provides a rare bridge between network theory and an evolved system, demonstrating social redundancy to be the mechanism by which resilience to perturbation occurred in this socially advanced species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synergistic effect of sodium and yeast in improving the efficiency of DSSC sensitized with extract from petals of Kigelia Africana

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Shalini, S.; Balasundaraprabhu, R.; Satish Kumar, T.; Sivakumaran, K.; Kannan, M. D.

2018-05-01

TiO2 nanostructures with two different dopants, sodium and yeast have been successfully synthesized by hydrothermal method. Doping sodium is found to extend the absorbance of TiO2 into the visible region as well as it acts as mordant in fixing and improving the absorption of dye. Yeast, as a dopant, can help in absorption of more anthocyanins from the natural dye extract by TiO2 and also aids in retaining the colour of the dye and increases the stability of the dye at varying pH. Anthocyanins are the major class of pigment present in the newly addressed maroon, velvety and trumpet shaped flower "Kigelia Africana". X-ray diffraction analysis revealed the formation of rutile phase for all the samples. Field Emission Scanning Electron microscopy images revealed the formation of nanorods and nanoflowers with change in dopant as well as their concentration. The photoelectric conversion efficiency of DSSC with undoped TiO2 photoelectrode is 0.87% and DSSC with 6% Na doped TiO2 photoelectrode is 1.56%. The efficiency of DSSC with 6% Na+6% yeast doped TiO2 photoelectrode is found to increase from 2.09% (DSSC with 6% Na+4% yeast doped TiO2 photoelectrode) to 2.31% on varying the dopant concentration. Doping is also found to increase the dye absorption and superior charge transport efficiency which in turn helps to improve the performance of DSSC.

Control Químico de la Mosca de los Establos, Stomoxys Calcitrans (L y Otros Insectos Asociados con Estipes de Palma Africana en Descomposición

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Ureta Sandino Eduardo

1972-12-01

Full Text Available En ensayos para determinar el efecto del diazinon 1% I.A. (ingrediente activo; bromophos 1 % I.A.; dieldrin 0.5% I.A., 2% I.A. y methomyl 0.1 % I.A. sobre larvas de Stomoxys calcilrans y otros insectos asociados con tipes de palma africana (Elaeis guineensis en descomposición, se encontró que los tratamientos con diazinon 1% I.A. y bromophos 1% I.A. fueron los más efectivos para impedir la proliferación en éstos de las larvas de Slomoxys calcilralls. Ambos insecticidas protegieron eficientemente los estipes por lo menos durante dos semanas. El dieldrin al 0.5% I. A. y 2% I. A., aunque inferior al bromophos 1% I.A. y al diazinon 1% I.A. también fue efectivo para impedir la proliferación de larvas de la mosca en los troncos de palma africana en descomposición. El tratamiento con methomyl 0.1 % I. A. al parecer no impidió la multiplicación de las larvas en los estipes, según pudo observarse en muestras tomadas a las dos semanas de haber sido aplicado el producto. El diazinon 1% I.A: bromophos 1 % I.A.; dieldrin 0.5% I.A. y 2% I.A., aparentemente fueron eficaces para controlar los adultos de Limnobaris calandriformis y Metamasius hemipterus, los cuales eran atraídos en grandes cantidades a los trozos de tallo de palma recién rajada, así como también impidieron la proliferación en éstos de las larvas de los dípteros Ormidea obesa y Hermelia sp./Abstract Several tests were carried out to determine the effectiveness of diazinon 1% I.A., bromophos 1% I.A., dieldrin 0.5 and 2% I.A., and methomyl 0.1 % on larvae of the stable fly, Stomoxys calcitrans, and other insects associated with dead trunks of the oil palm (Elaeis guineesis.The results showed by the author indicate that diazinon and bromophos were the most effective materials tested. Both insecticides protected well the dead trunks for at least two weeks. Dieldrin (both doses although less efficient than diazinon, was also effective in preventing the development of great numbers of

SETTING HEALTH PRIORITIES IN RESEARCH: AN AFRICAN PERSPECTIVE ESTABLECIMIENTO DE PRIORIDADES DE SALUD EN INVESTIGACIÓN: UNA PERSPECTIVA AFRICANA ESTABELECIMENTO DE PRIORIDADES DE SAÚDE NA PESQUISA: UMA PERSPECTIVA AFRICANA

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Angela Amondi Wasunna

2004-01-01

édicas diseñadas para mejorar la salud y, en la mayoría de los casos, requiere participación de seres humanos como sujetos de investigación. Éstos no pueden, sin embargo, verse en aislamiento; son parte de una comunidad, lo que implica una pregunta: ¿cómo se benefician las comunidades con la investigación que tiene lugar en ellas? En el mundo de la ética de la investigación se ha convertido en un mantra decir que las comunidades deben beneficiarse con los resultados positivos de la investigación. Esta norma ética es importante; sin embargo, mi artículo se enfoca en la participación de la comunidad antes de que se realice la investigación. Usando ejemplos de África como casos, examinaré hasta qué punto se incluye a las comunidades al establecer la agenda de investigación en salud, y si se les consulta al fijar prioridades. Puede que la investigación que se realiza en varias comunidades africanas responda a sus necesidades de salud; sin embargo, ¿cuán prioritarios son estos problemas para cada comunidad? ¿Son postergadas otras necesidades importantes de salud? Mientras que se ha dicho mucho sobre proveer tratamiento para la comunidad entera después de que la investigación ha demostrado ser eficaz, no se ha dicho lo suficiente sobre quién decide cuál investigación es importante para la comunidad antes de que se realiceAtualmente se realiza muita pesquisa biomédica e epidemiológica na África que é tanto horizontal (envolvendo pesquisadores locais e instituições regionais de pesquisa como vertical (envolvendo patrocinadores e colaboradores internacionais. A pesquisa é o caminho necessário para se conquistar inovações biomédicas para melhorar a saúde e, na maioria dos casos, exige a participação de seres humãos como sujeitos de pesquisa. Estes não podem ser vistos isoladamente, são parte de uma comunidade, o que implica um questionamento: que benefícios a pesquisa traz para a comunidade? No mundo da ética da pesquisa se transformou um

O dom e a iniciação revisitados: o dado e o feito em religiões de matriz africana no brasil

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Marcio Goldman

2012-08-01

Full Text Available Partindo da conhecida oposição entre o que derivaria do "dom" e o que derivaria da "iniciação" nas religiões de matriz africana no Brasil, este trabalho visa, em um primeiro movimento, demonstrar etnograficamente que esse dualismo oculta um triadismo. O desdobramento da análise etnográfica levará, contudo e em seguida, à substituição desse triadismo por um modelo simultaneamente unitário e múltiplo. Neste, a "participação", em seus múltiplos sentidos, deverá ter um lugar ao lado do "dom" e da "iniciação", e as três categorias deverão ser entendidas como atualizações de um princípio subjacente único.Beginning with the known opposition between that which derives from the "gift" and that which derives from "initiation" in African-oriented religions in Brazil, this work aims to ethnographically demonstrate that said dualism actually conceals a triadism. The unfolding of ethnographic analysis in the article will, however, lead us to replace this triadism with a model that is simultaneously unified and multiple. In this, "participation" (in its multiple meanings should have a place next to the "gift" and "initiation" and the three categories should be construed as updates of a single under-lying principle.

Benefits conferred by "timid" ants: active anti-herbivore protection of the rainforest tree Leonardoxa africana by the minute ant Petalomyrmex phylax.

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Gaume, Laurence; McKey, Doyle; Anstett, Marie-Charlotte

1997-10-01

In this study, we demonstrate that an important benefit provided by the small host-specific ant Petalomyrmex phylax to its host plant Leonardoxa africana is efficient protection against herbivores. We estimate that in the absence of ants, insect herbivory would reduce the leaf area by about one-third. This contributes considerably to the fitness of the plant. Our estimates take into account not only direct damage, such as removal of leaf surface by chewing insects, but also the effects of sucking insects on leaf growth and expansion. Sucking insects are numerically predominant in this system, and the hitherto cryptic effects of ant protection against the growth-reducing effects of sucking insects accounted for half of the total estimated benefit of ant protection. We propose that the small size of workers confers a distinct advantage in this system. Assuming that resource limitation implies a trade off between size and number of ants, and given the small size of phytophagous insects that attack Leonardoxa, we conclude that fine-grained patrolling by a large number of small workers maximises protection of young leaves of this plant. Since herbivores are small and must complete their development on the young leaves of Leonardoxa, and since a high patrolling density is required for a fine-grained search for these enemies, numerous small ants should provide the most effective protection of young leaves of Leonardoxa. We also discuss other factors that may have influenced worker size in this ant.

Attending to detail by communal spider-eating spiders.

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Jackson, Robert R; Nelson, Ximena J

2012-07-01

Communal predators may often need to make especially intricate foraging decisions, as a predator's success may depend on the actions of its neighbours. Here,we consider the decisions made by Portia africana, a jumping spider (Salticidae) that preys on other spiders, including Oecobius amboseli (Oecobiidae), a small prey spider that lives under small sheets of silk (nests) on the walls of buildings. P. africana juveniles settle near oecobiid nests and then ambush oecobiids as they leave or enter the nest. Two or more P. africana juveniles sometimes settle at the same nest and, when an oecobiid is captured, the P. africana juveniles may share the meal. We investigated the joining decisions made by naïve P. africana juveniles. Experiments were based on using lures (dead spiders positioned in lifelike posture) arranged in a series of 17 different scenes defined by the presence/absence of a nest, the lure types present and the configuration of the lures and the nest. Our findings imply that P. africana juveniles make remarkably precise predatory decisions, with the variables that matter including whether a nest is present, the identity of spiders inside and outside a nest and how spiders are positioned relative to each other and the nest.

Adaptación de la metodología de cálculo de huella ecológica para los cultivos de palma africana usando sistemas de información geográfica: estudio de caso Puerto Wilches Santande

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Claudia Ramírez Cano

2014-06-01

Full Text Available En el municipio de Puerto Wilches el monocultivo de palma africana actualmente es un eje trasversal de la economía, modificando la diversidad de los ecosistemas y cultivos tradicionales de la zona. Por lo cual, el objetivo de esta investigación es medir y evaluar los impactos de los cultivos de palma africana en el lapso de 1987 a 2010 adaptando la metodología desarrollada por Mathis Wackernagel y William Rees y algunos aportes de los desarrollos realizados por Juan Luis Doménech, aunando a estos tecnología satelital e indicadores de biocapacidad y déficit ecológico para conocer los requerimientos de espacios y recursos naturales necesarios para la producción de los derivados de la palma. El análisis de la época arrojó para el año 1987 un indicador de huella ecológica con un valor de 1.255 ha/pc, biocapacidad del cultivo 0.470 ha/pc, déficit ecológico correspondiente a -0.785 ha/pc; se estima un valor del 16 % en cuanto a la producción y uso de recursos. Con relación a los indicadores de sostenibilidad, en 2010 se obtuvieron valores de huella ecológica de 5.492 ha/pc, biocapacidad 1.454 ha/pc y déficit ecológico de -4.038 ha/pc, cifras que evidencian los efectos originados por la implementación del monocultivo en la zona, que para la fecha aumento en un 63 % la producción y uso de recursos naturales. Por lo anterior, es necesario y urgente elaborar e implementar políticas de planificación territorial así como alternativas de producción económica para mejorar la calidad ambiental y social del municipio, deteniendo la acelerada antropización de la región.

Enriching the captive elephant population genetic pool through artificial insemination with frozen-thawed semen collected in the wild.

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Hildebrandt, T B; Hermes, R; Saragusty, J; Potier, R; Schwammer, H M; Balfanz, F; Vielgrader, H; Baker, B; Bartels, P; Göritz, F

2012-10-01

The first successful AI in an elephant was reported in 1998, using fresh semen. Since then almost 40 calves have been produced through AI in both Asian and African elephants worldwide. Following these successes, with the objective of enriching the captive population with genetic material from the wild, we evaluated the possibility of using frozen-thawed semen collected from wild bulls for AI in captivity. Semen, collected from a 36-yr-old wild African savanna elephant (Loxodonta africana) in South Africa was frozen using the directional freezing technique. This frozen-thawed semen was used for four inseminations over two consecutive days, two before and two after ovulation, in a 26-yr-old female African savanna elephant in Austria. Insemination dose of 1200 × 10(6) cells per AI with 61% motility resulted in pregnancy, which was confirmed through ultrasound examination 75, 110 and 141 days after the AI procedure. This represents the first successful AI using wild bull frozen-thawed semen in elephants. The incorporation of AI with frozen-thawed semen into the assisted reproduction toolbox opens the way to preserve and transport semen between distant individuals in captivity or, as was done in this study, between wild and captive populations, without the need to transport stressed or potentially disease-carrying animals or to remove animals from the wild. In addition, cryopreserved spermatozoa, in combination with AI, are useful methods to extend the reproductive lifespan of individuals beyond their biological lifespan and an important tool for genetic diversity management and phenotype selection in these endangered mammals. Copyright © 2012 Elsevier Inc. All rights reserved.

Using Poaching Levels and Elephant Distribution to Assess the Conservation Efficacy of Private, Communal and Government Land in Northern Kenya.

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Ihwagi, Festus W; Wang, Tiejun; Wittemyer, George; Skidmore, Andrew K; Toxopeus, Albertus G; Ngene, Shadrack; King, Juliet; Worden, Jeffrey; Omondi, Patrick; Douglas-Hamilton, Iain

2015-01-01

Efforts to curb elephant poaching have focused on reducing demand, confiscating ivory and boosting security patrols in elephant range. Where land is under multiple uses and ownership, determining the local poaching dynamics is important for identifying successful conservation models. Using 2,403 verified elephant, Loxodonta africana, mortality records collected from 2002 to 2012 and the results of aerial total counts of elephants conducted in 2002, 2008 and 2012 for the Laikipia-Samburu ecosystem of northern Kenya, we sought to determine the influence of land ownership and use on diurnal elephant distribution and on poaching levels. We show that the annual proportions of illegally killed (i.e., poached) elephants increased over the 11 years of the study, peaking at 70% of all recorded deaths in 2012. The type of land use was more strongly related to levels of poaching than was the type of ownership. Private ranches, comprising only 13% of land area, hosted almost half of the elephant population and had significantly lower levels of poaching than other land use types except for the officially designated national reserves (covering only 1.6% of elephant range in the ecosystem). Communal grazing lands hosted significantly fewer elephants than expected, but community areas set aside for wildlife demonstrated significantly higher numbers of elephants and lower illegal killing levels relative to non-designated community lands. While private lands had lower illegal killing levels than community conservancies, the success of the latter relative to other community-held lands shows the importance of this model of land use for conservation. This work highlights the relationship between illegal killing and various land ownership and use models, which can help focus anti-poaching activities.

Inferring ecological and behavioral drivers of African elephant movement using a linear filtering approach.

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Boettiger, Alistair N; Wittemyer, George; Starfield, Richard; Volrath, Fritz; Douglas-Hamilton, Iain; Getz, Wayne M

2011-08-01

Understanding the environmental factors influencing animal movements is fundamental to theoretical and applied research in the field of movement ecology. Studies relating fine-scale movement paths to spatiotemporally structured landscape data, such as vegetation productivity or human activity, are particularly lacking despite the obvious importance of such information to understanding drivers of animal movement. In part, this may be because few approaches provide the sophistication to characterize the complexity of movement behavior and relate it to diverse, varying environmental stimuli. We overcame this hurdle by applying, for the first time to an ecological question, a finite impulse-response signal-filtering approach to identify human and natural environmental drivers of movements of 13 free-ranging African elephants (Loxodonta africana) from distinct social groups collected over seven years. A minimum mean-square error (MMSE) estimation criterion allowed comparison of the predictive power of landscape and ecological model inputs. We showed that a filter combining vegetation dynamics, human and physical landscape features, and previous movement outperformed simpler filter structures, indicating the importance of both dynamic and static landscape features, as well as habit, on movement decisions taken by elephants. Elephant responses to vegetation productivity indices were not uniform in time or space, indicating that elephant foraging strategies are more complex than simply gravitation toward areas of high productivity. Predictions were most frequently inaccurate outside protected area boundaries near human settlements, suggesting that human activity disrupts typical elephant movement behavior. Successful management strategies at the human-elephant interface, therefore, are likely to be context specific and dynamic. Signal processing provides a promising approach for elucidating environmental factors that drive animal movements over large time and spatial

Elephant Management in North American Zoos: Environmental Enrichment, Feeding, Exercise, and Training.

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Greco, Brian J; Meehan, Cheryl L; Miller, Lance J; Shepherdson, David J; Morfeld, Kari A; Andrews, Jeff; Baker, Anne M; Carlstead, Kathy; Mench, Joy A

2016-01-01

The management of African (Loxodonta africana) and Asian (Elephas maximus) elephants in zoos involves a range of practices including feeding, exercise, training, and environmental enrichment. These practices are necessary to meet the elephants' nutritional, healthcare, and husbandry needs. However, these practices are not standardized, resulting in likely variation among zoos as well as differences in the way they are applied to individual elephants within a zoo. To characterize elephant management in North America, we collected survey data from zoos accredited by the Association of Zoos and Aquariums, developed 26 variables, generated population level descriptive statistics, and analyzed them to identify differences attributable to sex and species. Sixty-seven zoos submitted surveys describing the management of 224 elephants and the training experiences of 227 elephants. Asian elephants spent more time managed (defined as interacting directly with staff) than Africans (mean time managed: Asians = 56.9%; Africans = 48.6%; pyear of age for both species. Enrichment, feeding, and exercise programs were evaluated using diversity indices, with mean scores across zoos in the midrange for these measures. There were an average of 7.2 feedings every 24-hour period, with only 1.2 occurring during the nighttime. Feeding schedules were predictable at 47.5% of zoos. We also calculated the relative use of rewarding and aversive techniques employed during training interactions. The population median was seven on a scale from one (representing only aversive stimuli) to nine (representing only rewarding stimuli). The results of our study provide essential information for understanding management variation that could be relevant to welfare. Furthermore, the variables we created have been used in subsequent elephant welfare analyses.

Department of Zoological Sciences, Addis Ababa Univer

African Journals Online (AJOL)

USER

2016-12-02

Dec 2, 2016 ... unprecedented negative effects thereby exasperating natural disasters which ultimately will cause a negative .... such farms there is substantial activity in animal husbandry. .... capensis, Prunus africana, Cordia africana, and ...

Comparative Evaluation of the Nutrients and Phytochemical ...

African Journals Online (AJOL)

Materials and Methods: The leaves (Ocimum gratissmium and Lasianthera africana) were randomly obtained from Umuahia Main Market and Uyo Central Market, respectively. ... Keywords: Phytochemicals, Ocimum gratissmium, Lasianthera africana proximate composition, mineral composition, Beta-carotene, Vitamin C ...

Antimicrobial activity and probable mechanisms of action of medicinal plants of Kenya: Withania somnifera, Warbugia ugandensis, Prunus africana and Plectrunthus barbatus.

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Peter G Mwitari

Full Text Available Withania somnifera, Warbugia ugandensis, Prunus africana and Plectrunthus barbatus are used traditionally in Kenya for treatment of microbial infections and cancer. Information on their use is available, but scientific data on their bioactivity, safety and mechanisms of action is still scanty. A study was conducted on the effect of organic extracts of these plants on both bacterial and fungal strains, and their mechanisms of action. Extracts were evaluated through the disc diffusion assay. Bacteria and yeast test strains were cultured on Mueller-Hinton agar and on Sabouraud dextrose agar for the filamentous fungi. A 0.5 McFarland standard suspension was prepared. Sterile paper discs 6 mm in diameter impregnated with 10 µl of the test extract (100 mg/ml were aseptically placed onto the surface of the inoculated media. Chloramphenicol (30 µg and fluconazole (25 µg were used as standards. Discs impregnated with dissolution medium were used as controls. Activity of the extracts was expressed according to zone of inhibition diameter. MIC was determined at 0.78-100 mg/ml. Safety studies were carried using Cell Counting Kit 8 cell proliferation assay protocol. To evaluate extracts mechanisms of action, IEC-6 cells and RT-PCR technique was employed in vitro to evaluate Interleukin 7 cytokine. Investigated plants extracts have both bactericidal and fungicidal activity. W. ugandensis is cytotoxic at IC50200 µg/ml. Fractions from W. ugandensis and W. somnifera too demonstrated antimicrobial activity. Mechanisms of action can largely be attributed to cytotoxicity, Gene silencing and immunopotentiation. Use of medicinal plants in traditional medicine has been justified and possible mechanisms of action demonstrated. Studies to isolate and characterize the bioactive constituents continue.

Telling Tales of War to Teens: Ignacio Martínez de Pisón's Una guerra africana and Morocco as "Open Wound" in the Spanish National Imaginary

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Silvia Bermúdez

2006-01-01

Full Text Available Exactly ten years after its traumatic defeat in the Spanish-American War of 1898, Spain appeared to find some compensation for the loss of its last colonies by undertaking the invasion of Morocco in 1908. The enterprise proved difficult when the forces of Abd-el-Krim defeated the Spanish army in the summer of 1921. This terrible loss was metaphorized as an "open wound" and entered the collective imagination by becoming a theme in novels such as José Díaz Fernández's El blocao (1928, Ramón Sender's Imán (1930, and Arturo Barea's series La forja de un rebelde (1941-1944. Known as the "Disaster of Annual," the defeat appeared to be almost forgotten until a series of narratives in the late twentieth and early twenty-first centuries obsessively returned to this particular moment of Spanish history. I focus on how one such narrative, Martínez de Pisón's Una guerra africana (2000, revisits this war as adolescent literature ("novelas juveniles" and within the literary genre of the "novels of the War in Africa," and by so doing, contributes to the articulation of a Spanish collective identity with the historical memory of the feared Moroccan Other.

Analysis of Price Variation and Market Integration of Prosopis ...

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Analysis of Price Variation and Market Integration of Prosopis Africana (guill. ... select five markets based on the presence of traders selling the commodity in the markets ... T- test result showed that Prosopis africana seed trade is profitable and ...

Em torno das "Diretrizes curriculares nacionais para a educação das relações étnico-raciais e para o ensino de história e cultura afro-brasileira e africana": uma conversa com historiadores

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Martha Abreu

2008-06-01

Full Text Available A partir do crescimento do interesse de professores e secretarias de educação na organização de políticas de combate ao racismo, este artigo procura discutir e apresentar alguns subsídios para a implementação das "Diretrizes curriculares nacionais para o ensino das relações étnico-raciais e de história e cultura afro-brasileira e africana", aprovadas em 2004. Entendemos as "Diretrizes" como uma importante estratégia pedagógica para levar à escola, pela primeira vez, a discussão das relações raciais no Brasil, tantas vezes silenciada ou desqualificada pelas avaliações de que o Brasil era uma democracia racial. Demos especial atenção aos limites e possibilidades de trabalho com os conceitos de cultura afro-brasileira e identidade negra.

2018-04-26T17:44:52Z https://www.ajol.info/index.php/all/oai oai:ojs ...

African Journals Online (AJOL)

article/31203 2018-04-26T17:44:52Z ajtcam:ART Acute And Subacute Toxicity Of Aspilia Africana Leaves Taziebou, LC Etoa, F-X Nkegoum, B Pieme, CA Dzeufiet, DPD Aspilia Africana, Asteraceae, toxicities, dose responsiveness. This study was ...

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African Journals Online (AJOL)

article/84776 2018-04-27T07:42:46Z jard:ART Nutritional Composition of the Flour of African Breadfruit (Treculia africana) Seeds Testa Adeyeye, EI Adesina, JA Chemical composition of the African breadfruit (Treculia africana) seeds testa was ...

Effect of domestic cooking on the starch digestibility, predicted glycemic indices, polyphenol contents and alpha amylase inhibitory properties of beans (Phaseolis vulgaris) and breadfruit (Treculia africana).

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Chinedum, E; Sanni, S; Theressa, N; Ebere, A

2018-01-01

The effect of processing on starch digestibility, predicted glycemic indices (pGI), polyphenol contents and alpha amylase inhibitory properties of beans (Phaseolis vulgaris) and breadfruit (Treculia africana) was studied. Total starch ranged from 4.3 to 68.3g/100g, digestible starch ranged from 4.3 to 59.2 to 65.7g/100g for the raw and processed legumes; Resistance starch was not detected in most of the legumes except in fried breadfruit and the starches in both the raw and processed breadfruit were more rapidly digested than those from raw and cooked beans. Raw and processed breadfruit had higher hydrolysis curves than raw and processed beans with the amylolysis level in raw breadfruit close to that of white bread. Raw beans had a low glycemic index (GI); boiled beans and breadfruit had intermediate glycemic indices respectively while raw and fried breadfruit had high glycemic indices. Aqueous extracts of the food samples had weak α-amylase inhibition compared to acarbose. The raw and processed legumes contained considerable amounts of dietary phenols and flavonoids. The significant correlation (r=0.626) between α-amylase inhibitory actions of the legumes versus their total phenolic contents suggests the contribution of the phenolic compounds in these legumes to their α-amylase inhibitory properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Julie N. Udensi Ph.D, Prof (Mrs) Virgina W. Dike EXTENT OF ...

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Keyword: Africana, University Libraries, Post Graduate, Students, Lecturers. ... Africa is endowed with diversity of culture which is the major source ofAfricana, however ... agricultural communication (theses) also buttressed this stating that African .... important role in the effective planning and management of any information.

Metabolic health assessment of zoo elephants: Management factors predicting leptin levels and the glucose-to-insulin ratio and their associations with health parameters.

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Kari A Morfeld

Full Text Available Screening for metabolic-related health problems can enhance animal welfare, so the purpose of this study was to conduct the first metabolic health assessment of zoo elephants and use epidemiological methods to determine how factors in the captive environment were associated with metabolic hormone concentrations. In addition, we examined relationships between metabolic status and several fitness parameters: foot health, musculoskeletal health, reproductive cyclicity, and body condition. Two blood samples were collected 2 weeks apart from 87 Asian (Elephas maximus and 105 African (Loxodonta africana elephants managed by zoos accredited by the Association of Zoos and Aquariums for analysis of serum leptin, insulin, glucose and the glucose-to-insulin ratio (G:I. In females, mean (± SD leptin concentrations and the G:I were lower (P0.05. As mean leptin concentration increased there was an increase in the odds of a female being non-cycling (P = 0.0083. The G:I was associated inversely with body condition (P = 0.0002; as the G:I increased there was a decreased risk of BCS = 4 or 5 as compared to the ideal, or BCS = 3. Neither leptin nor G:I were predictive of foot or musculoskeletal health scores. Factors related to walking and feeding practices were most influential in predicting metabolic status, whereas social and housing factors showed smaller, but significant effects. The metabolic health benefits of walking were detected if the time spent in staff-directed walking was 7 hours or more per week. The most protective feeding practices included implementing a random rather than predictable feeding schedule and limiting the number of methods presentation methods. Results indicate that leptin levels and G:I can be used as predictors of both ovarian cycle function and body condition, and are affected by zoo management in elephants.

Impacts of ungulates on the demography and diversity of small mammals in central Kenya.

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Keesing, Felicia

1998-09-01

The impacts of ungulates on small mammals in an East African savanna habitat were investigated by monitoring the population and community responses of small mammals on replicated 4-ha plots from which ungulates had been excluded. The dominant small mammal in this habitat is the pouched mouse, Saccostomusmearnsi, a medium-sized murid rodent. Eight other small mammal species, including Arvicanthis sp., Mus sp., Mastomys sp., Dendromus sp., Crocidura sp., and, rarely, Tatera sp., Aethomys sp., and Acomys sp., were also captured. The dominant ungulates are elephant (Loxodonta africana), giraffe (Giraffa camelopardalis), Grevy's and common zebra (Equus grevyi and E. burchelli), buffalo (Syncerus cafer), eland (Taurotragus oryx), Grant's gazelle (Gazella granti), and domestic cattle. Within 1 year, S. mearnsi populations had responded dramatically to the exclusion of large mammals by a two-fold increase in density, a difference that was maintained through pronounced seasonal fluctuations in the second year. Though individual pouched mice showed no significant differences in their use of space with and without ungulates, male S. mearnsi maintained significantly higher body weights in the absence of ungulates, indicating that habitat quality had increased. One other species, Mastomys sp., also increased in the absence of ungulates. Overall, the small mammal community maintained relatively constant species diversity on the plots to which ungulates did not have access. On the plots to which ungulates did have access, on the other hand, there was a rapid 75% decrease in diversity in the control plots during one trapping session. Ungulates are most likely affecting small mammals through their effects on food quality, since there were no detectable differences in their exposure to predators, as determined by vegetative cover, in the absence of ungulates. These results demonstrate that ungulates can have strong and rapid impacts on small mammal abundance and diversity in East

Interspecific interference competition at the resource patch scale: do large herbivores spatially avoid elephants while accessing water?

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Ferry, Nicolas; Dray, Stéphane; Fritz, Hervé; Valeix, Marion

2016-11-01

Animals may anticipate and try to avoid, at some costs, physical encounters with other competitors. This may ultimately impact their foraging distribution and intake rates. Such cryptic interference competition is difficult to measure in the field, and extremely little is known at the interspecific level. We tested the hypothesis that smaller species avoid larger ones because of potential costs of interference competition and hence expected them to segregate from larger competitors at the scale of a resource patch. We assessed fine-scale spatial segregation patterns between three African herbivore species (zebra Equus quagga, kudu Tragelaphus strepsiceros and giraffe Giraffa camelopardalis) and a megaherbivore, the African elephant Loxodonta africana, at the scale of water resource patches in the semi-arid ecosystem of Hwange National Park, Zimbabwe. Nine waterholes were monitored every two weeks during the dry season of a drought year, and observational scans of the spatial distribution of all herbivores were performed every 15 min. We developed a methodological approach to analyse such fine-scale spatial data. Elephants increasingly used waterholes as the dry season progressed, as did the probability of co-occurrence and agonistic interaction with elephants for the three study species. All three species segregated from elephants at the beginning of the dry season, suggesting a spatial avoidance of elephants and the existence of costs of being close to them. However, contrarily to our expectations, herbivores did not segregate from elephants the rest of the dry season but tended to increasingly aggregate with elephants as the dry season progressed. We discuss these surprising results and the existence of a trade-off between avoidance of interspecific interference competition and other potential factors such as access to quality water, which may have relative associated costs that change with the time of the year. © 2016 The Authors. Journal of Animal Ecology �

DUST-BATHING BEHAVIORS OF AFRICAN HERBIVORES AND THE POTENTIAL RISK OF INHALATIONAL ANTHRAX.

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Barandongo, Zoe R; Mfune, John K E; Turner, Wendy C

2018-01-01

:  Anthrax in herbivorous wildlife and livestock is generally assumed to be transmitted via ingestion or inhalation of Bacillus anthracis spores. Although recent studies have highlighted the importance of the ingestion route for anthrax transmission, little is known about the inhalational route in natural systems. Dust bathing could aerosolize soilborne pathogens such as B. anthracis, exposing dust-bathing individuals to inhalational infections. We investigated the potential role of dust bathing in the transmission of inhalational anthrax to herbivorous wildlife in Etosha National Park, Namibia, an area with endemic seasonal anthrax outbreaks. We 1) cultured soils from dust-bathing sites for the presence and concentration of B. anthracis spores, 2) monitored anthrax carcass sites, the locations with the highest B. anthracis concentrations, for evidence of dust bathing, including a site where a zebra died of anthrax on a large dust bath, and 3) characterized the ecology and seasonality of dust bathing in plains zebra ( Equus quagga), blue wildebeest ( Connochaetes taurinus), and African savanna elephant ( Loxodonta africana) using a combination of motion-sensing camera traps and direct observations. Only two out of 83 dust-bath soils were positive for B. anthracis, both with low spore concentrations (≤20 colony-forming units per gram). We also detected no evidence of dust baths occurring at anthrax carcass sites, perhaps due to carcass-induced changes in soil composition that may deter dust bathing. Finally, despite observing some seasonal variation in dust bathing, preliminary evidence suggests that the seasonality of dust bathing and anthrax mortalities are not correlated. Thus, although dust bathing creates a dramatic cloud of aerosolized soil around an individual, our microbiologic, ecologic, and behavioral results in concert demonstrate that dust bathing is highly unlikely to transmit inhalational anthrax infections.

Freezing African elephant semen as a new population management tool.

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Robert Hermes

Full Text Available BACKGROUND: The captive elephant population is not self-sustaining and with a limited number of breeding bulls, its genetic diversity is in decline. One way to overcome this is to import young and healthy animals from the wild. We introduce here a more sustainable alternative method - importation of semen from wild bulls without removing them from their natural habitat. Due to the logistics involved, the only practical option would be to transport cryopreserved sperm. Despite some early reports on African elephant semen cryopreservation, the utility of this new population management tool has not been evaluated. METHODOLOGY/PRINCIPAL FINDINGS: Semen was collected by electroejaculation from 14 wild African savanna elephant (Loxodonta africana bulls and cryopreserved using the directional freezing technique. Sperm treatments evaluated included the need for centrifugation, the use of hen or quail yolk, the concentration of glycerol (3%, 5% or 7% in the extender, and maintenance of motility over time after thawing. Our results suggest that dilution in an extender containing hen yolk and 7% glycerol after centrifugation best preserved post-thaw sperm motility when compared to all other treatments (P≤0.012 for all. Using this approach we were able to achieve after thawing (mean ± SD 54.6±3.9% motility, 85.3±2.4% acrosome integrity, and 86.8±4.6% normal morphology with no decrease in motility over 1 h incubation at 37°C. Sperm cryopreserved during this study has already lead to a pregnancy of a captive female elephant following artificial insemination. CONCLUSIONS/SIGNIFICANCE: With working techniques for artificial insemination and sperm cryopreservation of both African and Asian elephants in hand, population managers can now enrich captive or isolated wild elephant populations without removing valuable individuals from their natural habitat.

Detusking fence-breaker elephants as an approach in human-elephant conflict mitigation.

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Mutinda, Matthew; Chenge, Geoffrey; Gakuya, Francis; Otiende, Moses; Omondi, Patrick; Kasiki, Samuel; Soriguer, Ramón C; Alasaad, Samer

2014-01-01

Human-elephant conflict (HEC) is a recurring problem that appears wherever the range of elephants and humans overlap. Different methods including the use of electric fences are used worldwide to mitigate this conflict. Nonetheless, elephants learn quickly that their tusks do not conduct electricity and use them to break down fences (fence-breakers). In Lewa Wildlife Conservancy, Kenya, destructive elephants (Loxodonta africana) were monitored between 2010 and 2013. The fence-breaking rate reached four incidents (fence-breaking) per elephant per 100 days. Ten bull males and 57 females were identified as fence-breakers. The bulls were involved in 85.07% and the females in 14.93% of incidents. The Kenya Wildlife Service approved detusking (partial cutting of tusks) in four of the 10 fence-breakers as a way of preventing them from breaking down fences, thereby mitigating HEC in the Conservancy. The result of the detusking was a drastic six-fold reduction in damage to fences (range: 1.67 to 14.5 times less fence-breaking) by the four worst fence-breaker elephants, because with trimmed tusks elephants lack the tools to break down fences. Detusking could not totally eliminate fence destruction because, despite lacking their tools, elephants can still destroy fences using their heads, bodies and trunks, albeit less effectively. On the other hand, apart from inherent aesthetic considerations, the detusking of elephants may have certain negative effects on factors such as elephants' social hierarchies, breeding, mate selection and their access to essential minerals and food. Elephant detusking seems to be effective in drastically reducing fence-breaking incidents, nonetheless its negative effects on behaviour, access to food and its aesthetical consequences still need to be further studied and investigated.

Detusking fence-breaker elephants as an approach in human-elephant conflict mitigation.

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Matthew Mutinda

Full Text Available Human-elephant conflict (HEC is a recurring problem that appears wherever the range of elephants and humans overlap. Different methods including the use of electric fences are used worldwide to mitigate this conflict. Nonetheless, elephants learn quickly that their tusks do not conduct electricity and use them to break down fences (fence-breakers.In Lewa Wildlife Conservancy, Kenya, destructive elephants (Loxodonta africana were monitored between 2010 and 2013. The fence-breaking rate reached four incidents (fence-breaking per elephant per 100 days. Ten bull males and 57 females were identified as fence-breakers. The bulls were involved in 85.07% and the females in 14.93% of incidents. The Kenya Wildlife Service approved detusking (partial cutting of tusks in four of the 10 fence-breakers as a way of preventing them from breaking down fences, thereby mitigating HEC in the Conservancy. The result of the detusking was a drastic six-fold reduction in damage to fences (range: 1.67 to 14.5 times less fence-breaking by the four worst fence-breaker elephants, because with trimmed tusks elephants lack the tools to break down fences. Detusking could not totally eliminate fence destruction because, despite lacking their tools, elephants can still destroy fences using their heads, bodies and trunks, albeit less effectively. On the other hand, apart from inherent aesthetic considerations, the detusking of elephants may have certain negative effects on factors such as elephants' social hierarchies, breeding, mate selection and their access to essential minerals and food.Elephant detusking seems to be effective in drastically reducing fence-breaking incidents, nonetheless its negative effects on behaviour, access to food and its aesthetical consequences still need to be further studied and investigated.

Preliminary validation of assays to measure parameters of calcium metabolism in captive Asian and African elephants in western Europe.

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van Sonsbeek, Gerda R; van der Kolk, Johannes H; van Leeuwen, Johannes P T M; Schaftenaar, Willem

2011-05-01

Hypocalcemia is a well known cause of dystocia in animals, including elephants in captivity. In order to study calcium metabolism in elephants, it is of utmost importance to use properly validated assays, as these might be prone to specific matrix effects in elephant blood. The aim of the current study was to conduct preliminary work for validation of various parameters involved in calcium metabolism in both blood and urine of captive elephants. Basal values of these parameters were compared between Asian elephants (Elephas maximus) and African elephants (Loxodonta africana). Preliminary testing of total calcium, inorganic phosphorus, and creatinine appeared valid for use in plasma and creatinine in urine in both species. Furthermore, measurements of bone alkaline phosphatase and N-terminal telopeptide of type I collagen appeared valid for use in Asian elephants. Mean heparinized plasma ionized calcium concentration and pH were not significantly affected by 3 cycles of freezing and thawing. Storage at 4 °C, room temperature, and 37 °C for 6, 12, and 24 hr did not alter the heparinized plasma ionized calcium concentration in Asian elephants. The following linear regression equation using pH (range: 6.858-7.887) and ionized calcium concentration in heparinized plasma was utilized: iCa(7.4) (mmol/l) = -2.1075 + 0.3130·pH(actual) + 0.8296·iCa(actual) (mmol/l). Mean basal values for pH and plasma in Asian elephant whole blood were 7.40 ± 0.048 and 7.49 ± 0.077, respectively. The urinary specific gravity and creatinine concentrations in both Asian and African elephants were significantly correlated and both were significantly lower in Asian elephants. © 2011 The Author(s)

Determining Connections between the Daily Lives of Zoo Elephants and Their Welfare: An Epidemiological Approach.

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Cheryl L Meehan

Full Text Available Concerns about animal welfare increasingly shape people's views about the acceptability of keeping animals for food production, biomedical research, and in zoos. The field of animal welfare science has developed over the past 50 years as a method of investigating these concerns via research that assesses how living in human-controlled environments influences the behavior, health and affective states of animals. Initially, animal welfare research focused on animals in agricultural settings, but the field has expanded to zoos because good animal welfare is essential to zoos' mission of promoting connections between animals and visitors and raising awareness of conservation issues. A particular challenge for zoos is ensuring good animal welfare for long-lived, highly social species like elephants. Our main goal in conducting an epidemiological study of African (Loxodonta africana and Asian (Elephas maximus elephant welfare in 68 accredited North American zoos was to understand the prevalence of welfare indicators in the population and determine the aspects of an elephant's zoo environment, social life and management that are most important to prevent and reduce a variety of welfare problems. In this overview, we provide a summary of the findings of the nine papers in the collection titled: Epidemiological Investigations of North American Zoo Elephant Welfare with a focus on the life history, social, housing, and management factors found to be associated with particular aspects of elephant welfare, including the performance of abnormal behavior, foot and joint problems, recumbence, walking rates, and reproductive health issues. Social and management factors were found to be important for multiple indicators of welfare, while exhibit space was found to be less influential than expected. This body of work results from the largest prospective zoo-based animal welfare study conducted to date and sets in motion the process of using science-based welfare

Understanding tourists' preference for mammal species in private protected areas: is there a case for extralimital species for ecotourism?

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Kristine Maciejewski

Full Text Available Private Protected Areas (PPAs often use wildlife-based ecotourism as their primary means of generating business. Achieving tourist satisfaction has become a strong driving goal in the management of many PPAs, often at the expense of biodiversity. Many extralimitral species, those which historically did not occur in an area, are stocked in PPAs with the intention of increasing ecotourism attractions. Even though the ecological and economic costs of stocking these species are high, the social benefits are not understood and little information exists globally on the ecotourism role of extralimital species. This study assessed the value of stocking extralimital species using questionnaire-based surveys and observing tourists in Shamwari Private Game Reserve in the Eastern Cape Province of South Africa. No difference was found between indigenous and extralimital species with regards to the tourists' weighted scoring system, average amount tourists were willing to pay, total viewing time, average viewing time or the likelihood of stopping to view species when encountered on game drives. During game drives a strong preference was found for the elephant (Loxodonta africana, lion (Panthera leo, leopard (Panthera pardus and cheetah (Acynonix jubatus. With the exception of the cheetah, these species are all members of the "big five" and are indigenous. Species availability and visibility, however, may influence the amount of time tourists spend at an animal sighting. Our analysis suggests that certain extralimital species (typically larger and charismatic species contribute to tourist satisfaction, while particularly the smaller extralimital species add little to the game viewing experience, but add to the costs and risks of the PPAs. We recommend that extralimital species introductions for ecotourism purposes should be approached with caution with regards to the risks to the sustainability of PPAs.

The role of foraging behaviour in the sexual segregation of the African elephant.

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Shannon, Graeme; Page, Bruce R; Duffy, Kevin J; Slotow, Rob

2006-11-01

Elephants (Loxodonta africana) exhibit pronounced sexual dimorphism, and in this study we test the prediction that the differences in body size and sociality are significant enough to drive divergent foraging strategies and ultimately sexual segregation. Body size influences the foraging behaviour of herbivores through the differential scaling coefficients of metabolism and gut size, with larger bodied individuals being able to tolerate greater quantities of low-quality, fibrous vegetation, whilst having lower mass-specific energy requirements. We test two distinct theories: the scramble competition hypothesis (SCH) and the forage selection hypothesis (FSH). Comprehensive behavioural data were collected from the Pongola Game Reserve and the Phinda Private Game Reserve in South Africa over a 2.5-year period. The data were analysed using sex as the independent variable. Adult females targeted a wider range of species, adopted a more selective foraging approach and exhibited greater bite rates as predicted by the body size hypothesis and the increased demands of reproductive investment (lactation and pregnancy). Males had longer feeding bouts, displayed significantly more destructive behaviour (31% of observations, 11% for females) and ingested greater quantities of forage during each feeding bout. The independent ranging behaviour of adult males enables them to have longer foraging bouts as they experience fewer social constraints than females. The SCH was rejected as a cause of sexual segregation due to the relative abundance of low quality forage, and the fact that feeding heights were similar for both males and females. However, we conclude that the differences in the foraging strategies of the sexes are sufficient to cause spatial segregation as postulated by the FSH. Sexual dimorphism and the associated behavioural differences have important implications for the management and conservation of elephant and other dimorphic species, with the sexes effectively

Trophy Hunting and Sustainability: Temporal Dynamics in Trophy Quality and Harvesting Patterns of Wild Herbivores in a Tropical Semi-Arid Savanna Ecosystem.

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Muposhi, Victor K; Gandiwa, Edson; Bartels, Paul; Makuza, Stanley M; Madiri, Tinaapi H

2016-01-01

The selective nature of trophy hunting may cause changes in desirable phenotypic traits in harvested species. A decline in trophy size of preferred species may reduce hunting destination competitiveness thus compromising the sustainability of trophy hunting as a conservation tool. We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of Cape buffalo (Syncerus caffer), African elephant (Loxodonta africana), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. To analyse the effect of year, area and age on the trophy size, quota size and offtake levels, we used linear mixed models. One sample t-test was used to compare observed trophy size with Safari Club International (SCI) minimum score. Trophy sizes for Cape buffalo and African elephant were below the SCI minimum score. Greater kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015. Age at harvest for Cape buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of African elephant and Greater kudu declined whilst the quota size did not change between 2004 and 2015. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004-2015. The trophy size and harvesting patterns in these species pose a conservation and management dilemma on the sustainability of trophy hunting in this area. We recommend: (1) temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, and (2) introduction of variable trophy fee pricing system based on trophy size.

Animal perception of seasonal thresholds: changes in elephant movement in relation to rainfall patterns.

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Birkett, Patricia J; Vanak, Abi T; Muggeo, Vito M R; Ferreira, Salamon M; Slotow, Rob

2012-01-01

The identification of temporal thresholds or shifts in animal movement informs ecologists of changes in an animal's behaviour, which contributes to an understanding of species' responses in different environments. In African savannas, rainfall, temperature and primary productivity influence the movements of large herbivores and drive changes at different scales. Here, we developed a novel approach to define seasonal shifts in movement behaviour by examining the movements of a highly mobile herbivore (elephant; Loxodonta africana), in relation to local and regional rainfall patterns. We used speed to determine movement changes of between 8 and 14 GPS-collared elephant cows, grouped into five spatial clusters, in Kruger National Park, South Africa. To detect broad-scale patterns of movement, we ran a three-year daily time-series model for each individual (2007-2009). Piecewise regression models provided the best fit for elephant movement, which exhibited a segmented, waveform pattern over time. Major breakpoints in speed occurred at the end of the dry and wet seasons of each year. During the dry season, female elephant are constrained by limited forage and thus the distances they cover are shorter and less variable. Despite the inter-annual variability of rainfall, speed breakpoints were strongly correlated with both local and regional rainfall breakpoints across all three years. Thus, at a multi-year scale, rainfall patterns significantly affect the movements of elephant. The variability of both speed and rainfall breakpoints across different years highlights the need for an objective definition of seasonal boundaries. By using objective criteria to determine behavioural shifts, we identified a biologically meaningful indicator of major changes in animal behaviour in different years. We recommend the use of such criteria, from an animal's perspective, for delineating seasons or other extrinsic shifts in ecological studies, rather than arbitrarily fixed definitions

Elephant Management in North American Zoos: Environmental Enrichment, Feeding, Exercise, and Training.

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Brian J Greco

Full Text Available The management of African (Loxodonta africana and Asian (Elephas maximus elephants in zoos involves a range of practices including feeding, exercise, training, and environmental enrichment. These practices are necessary to meet the elephants' nutritional, healthcare, and husbandry needs. However, these practices are not standardized, resulting in likely variation among zoos as well as differences in the way they are applied to individual elephants within a zoo. To characterize elephant management in North America, we collected survey data from zoos accredited by the Association of Zoos and Aquariums, developed 26 variables, generated population level descriptive statistics, and analyzed them to identify differences attributable to sex and species. Sixty-seven zoos submitted surveys describing the management of 224 elephants and the training experiences of 227 elephants. Asian elephants spent more time managed (defined as interacting directly with staff than Africans (mean time managed: Asians = 56.9%; Africans = 48.6%; p<0.001, and managed time increased by 20.2% for every year of age for both species. Enrichment, feeding, and exercise programs were evaluated using diversity indices, with mean scores across zoos in the midrange for these measures. There were an average of 7.2 feedings every 24-hour period, with only 1.2 occurring during the nighttime. Feeding schedules were predictable at 47.5% of zoos. We also calculated the relative use of rewarding and aversive techniques employed during training interactions. The population median was seven on a scale from one (representing only aversive stimuli to nine (representing only rewarding stimuli. The results of our study provide essential information for understanding management variation that could be relevant to welfare. Furthermore, the variables we created have been used in subsequent elephant welfare analyses.

Trophy Hunting and Sustainability: Temporal Dynamics in Trophy Quality and Harvesting Patterns of Wild Herbivores in a Tropical Semi-Arid Savanna Ecosystem.

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Victor K Muposhi

Full Text Available The selective nature of trophy hunting may cause changes in desirable phenotypic traits in harvested species. A decline in trophy size of preferred species may reduce hunting destination competitiveness thus compromising the sustainability of trophy hunting as a conservation tool. We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015 of Cape buffalo (Syncerus caffer, African elephant (Loxodonta africana, greater kudu (Tragelaphus strepsiceros and sable (Hippotragus niger in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. To analyse the effect of year, area and age on the trophy size, quota size and offtake levels, we used linear mixed models. One sample t-test was used to compare observed trophy size with Safari Club International (SCI minimum score. Trophy sizes for Cape buffalo and African elephant were below the SCI minimum score. Greater kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015. Age at harvest for Cape buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of African elephant and Greater kudu declined whilst the quota size did not change between 2004 and 2015. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004-2015. The trophy size and harvesting patterns in these species pose a conservation and management dilemma on the sustainability of trophy hunting in this area. We recommend: (1 temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, and (2 introduction of variable trophy fee pricing system based on trophy size.

Animal perception of seasonal thresholds: changes in elephant movement in relation to rainfall patterns.

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Patricia J Birkett

Full Text Available BACKGROUND: The identification of temporal thresholds or shifts in animal movement informs ecologists of changes in an animal's behaviour, which contributes to an understanding of species' responses in different environments. In African savannas, rainfall, temperature and primary productivity influence the movements of large herbivores and drive changes at different scales. Here, we developed a novel approach to define seasonal shifts in movement behaviour by examining the movements of a highly mobile herbivore (elephant; Loxodonta africana, in relation to local and regional rainfall patterns. METHODOLOGY/PRINCIPAL FINDINGS: We used speed to determine movement changes of between 8 and 14 GPS-collared elephant cows, grouped into five spatial clusters, in Kruger National Park, South Africa. To detect broad-scale patterns of movement, we ran a three-year daily time-series model for each individual (2007-2009. Piecewise regression models provided the best fit for elephant movement, which exhibited a segmented, waveform pattern over time. Major breakpoints in speed occurred at the end of the dry and wet seasons of each year. During the dry season, female elephant are constrained by limited forage and thus the distances they cover are shorter and less variable. Despite the inter-annual variability of rainfall, speed breakpoints were strongly correlated with both local and regional rainfall breakpoints across all three years. Thus, at a multi-year scale, rainfall patterns significantly affect the movements of elephant. The variability of both speed and rainfall breakpoints across different years highlights the need for an objective definition of seasonal boundaries. CONCLUSIONS/SIGNIFICANCE: By using objective criteria to determine behavioural shifts, we identified a biologically meaningful indicator of major changes in animal behaviour in different years. We recommend the use of such criteria, from an animal's perspective, for delineating seasons or

Habitat Heterogeneity Variably Influences Habitat Selection by Wild Herbivores in a Semi-Arid Tropical Savanna Ecosystem.

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Victor K Muposhi

Full Text Available An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats.

Legal ivory trade in a corrupt world and its impact on African elephant populations.

Science.gov (United States)

Bennett, Elizabeth L

2015-02-01

Illegal hunting of African elephants (Loxodonta africana) for ivory is causing rapid declines in their populations. Since 2007, illegal ivory trade has more than doubled. African elephants are facing the most serious conservation crisis since 1989, when international trade was banned. One solution proposed is establishment of a controlled legal trade in ivory. High prices for ivory mean that the incentives to obtain large quantities are high, but the quantity of tusks available for trade are biologically constrained. Within that context, effective management of a legal ivory trade would require robust systems to be in place to ensure that ivory from illegally killed elephants cannot be laundered into a legal market. At present, that is not feasible due to corruption among government officials charged with implementing wildlife-related legislation. With organized criminal enterprises involved along the whole commodity chain, corruption enables the laundering of illegal ivory into legal or potentially legal markets. Poachers and traffickers can rapidly pay their way out of trouble, so the financial incentives to break the law heavily outweigh those of abiding by it. Maintaining reliable permitting systems and leak-proof chains of custody in this context is challenging, and effective management breaks down. Once illegal ivory has entered the legal trade, it is difficult or impossible for enforcement officers to know what is legal and illegal. Addressing corruption throughout a trade network that permeates countries across the globe will take decades, if it can ever be achieved. That will be too late for wild African elephants at current rates of loss. If we are to conserve remaining wild populations, we must close all markets because, under current levels of corruption, they cannot be controlled in a way that does not provide opportunities for illegal ivory being laundered into legal markets. © 2014 Society for Conservation Biology.

Understanding Tourists’ Preference for Mammal Species in Private Protected Areas: Is There a Case for Extralimital Species for Ecotourism?

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Maciejewski, Kristine; Kerley, Graham I. H.

2014-01-01

Private Protected Areas (PPAs) often use wildlife-based ecotourism as their primary means of generating business. Achieving tourist satisfaction has become a strong driving goal in the management of many PPAs, often at the expense of biodiversity. Many extralimitral species, those which historically did not occur in an area, are stocked in PPAs with the intention of increasing ecotourism attractions. Even though the ecological and economic costs of stocking these species are high, the social benefits are not understood and little information exists globally on the ecotourism role of extralimital species. This study assessed the value of stocking extralimital species using questionnaire-based surveys and observing tourists in Shamwari Private Game Reserve in the Eastern Cape Province of South Africa. No difference was found between indigenous and extralimital species with regards to the tourists’ weighted scoring system, average amount tourists were willing to pay, total viewing time, average viewing time or the likelihood of stopping to view species when encountered on game drives. During game drives a strong preference was found for the elephant (Loxodonta africana), lion (Panthera leo), leopard (Panthera pardus) and cheetah (Acynonix jubatus). With the exception of the cheetah, these species are all members of the “big five” and are indigenous. Species availability and visibility, however, may influence the amount of time tourists spend at an animal sighting. Our analysis suggests that certain extralimital species (typically larger and charismatic species) contribute to tourist satisfaction, while particularly the smaller extralimital species add little to the game viewing experience, but add to the costs and risks of the PPAs. We recommend that extralimital species introductions for ecotourism purposes should be approached with caution with regards to the risks to the sustainability of PPAs. PMID:24505426

Elevated elephant density does not improve ecotourism opportunities: convergence in social and ecological objectives.

Science.gov (United States)

Maciejewski, Kristine; Kerley, Graham I H

2014-07-01

In order to sustainably conserve biodiversity, many protected areas, particularly private protected areas, must find means of self-financing. Ecotourism is increasingly seen as a mechanism to achieve such financial sustainability. However, there is concern that ecotourism operations are driven to achieve successful game-viewing, influencing the management of charismatic species. An abundance of such species, including the African elephant (Loxodonta africana), has been stocked in protected areas under the assumption that they will increase ecotourism value. At moderate to high densities, the impact of elephants is costly; numerous studies have documented severe changes in biodiversity through the impacts of elephants. Protected areas that focus on maintaining high numbers of elephants may therefore face a conflict between socioeconomic demands and the capacity of ecological systems. We address this conflict by analyzing tourist elephant-sighting records from six private and one statutory protected area, the Addo Elephant National Park (AENP), in the Eastern Cape Province of South Africa, in relation to elephant numbers. We found no relationship between elephant density and elephant-viewing success. Even though elephant density in the AENP increased over time, a hierarchical partitioning analysis indicated that elephant density was not a driver of tourist numbers. In contrast, annual tourist numbers for the AENP were positively correlated with general tourist numbers recorded for South Africa. Our results indicate that the socioeconomic and ecological requirements of protected areas in terms of tourism and elephants, respectively, converge. Thus, high elephant densities and their associated ecological costs are not required to support ecotourism operations for financial sustainability. Understanding the social and ecological feedbacks that dominate the dynamics of protected areas, particularly within private protected areas, can help to elucidate the management

Understanding tourists' preference for mammal species in private protected areas: is there a case for extralimital species for ecotourism?

Science.gov (United States)

Maciejewski, Kristine; Kerley, Graham I H

2014-01-01

Private Protected Areas (PPAs) often use wildlife-based ecotourism as their primary means of generating business. Achieving tourist satisfaction has become a strong driving goal in the management of many PPAs, often at the expense of biodiversity. Many extralimitral species, those which historically did not occur in an area, are stocked in PPAs with the intention of increasing ecotourism attractions. Even though the ecological and economic costs of stocking these species are high, the social benefits are not understood and little information exists globally on the ecotourism role of extralimital species. This study assessed the value of stocking extralimital species using questionnaire-based surveys and observing tourists in Shamwari Private Game Reserve in the Eastern Cape Province of South Africa. No difference was found between indigenous and extralimital species with regards to the tourists' weighted scoring system, average amount tourists were willing to pay, total viewing time, average viewing time or the likelihood of stopping to view species when encountered on game drives. During game drives a strong preference was found for the elephant (Loxodonta africana), lion (Panthera leo), leopard (Panthera pardus) and cheetah (Acynonix jubatus). With the exception of the cheetah, these species are all members of the "big five" and are indigenous. Species availability and visibility, however, may influence the amount of time tourists spend at an animal sighting. Our analysis suggests that certain extralimital species (typically larger and charismatic species) contribute to tourist satisfaction, while particularly the smaller extralimital species add little to the game viewing experience, but add to the costs and risks of the PPAs. We recommend that extralimital species introductions for ecotourism purposes should be approached with caution with regards to the risks to the sustainability of PPAs.

Sunbirds hover at flowers of Salvia and Lycium | Wester | Ostrich ...

African Journals Online (AJOL)

Here I present detailed observations of foraging behaviour in two sunbird species (Malachite Sunbird Nectarinia famosa and Southern Double-collared Sunbird Cinnyris chalybeus) at flowers of three Salvia species (Salvia africana-lutea, S. lanceolata and S. africana-caerulea; Lamiaceae) and one natural hybrid as well as ...

The immunotoxicity of Dicerothamnus rhinocerotis and Galenia ...

African Journals Online (AJOL)

This paper describes the immunotoxicity of extracts of D. rhinocerotis and G. africana on mouse spleenocytes. Spleen cell cultures were prepared and exposed to varying concentrations of D. rhinocerotis and G. africana. Control cultures were exposed to the DMSO vehicle only. Results obtained showed that both D.

In vitro antimicrobial and phytochemical properties of crude extract ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... concentration of 25 mg/ml against twenty-one of the bacterial isolates, ... Key words: Afzelia africana, antimicrobial, phytochemical properties, ... A. africana mixed with millet beer has been found to ..... effects, cytostatic and antioxidant properties (Hodek et .... Role of plant polyphenols in genomic stability.

Combining ability of elephant grass based on nutritional characters

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Vanessa Quitete Ribeiro da Silva

2014-03-01

Full Text Available The objective of the work was to evaluate the effects of general combining ability (CGC of the parents and specific combining ability (CEC in the elephant grass hybrids by diallel analysis adapted to partial diallel crosses based on nutritional characters. Sixteen hybrids and eight parents in a randomized block design with three replications were evaluated. The study considered percentage of dry matter (%DM, ash (%ASH, crude protein (%CP and neutral detergent fiber (NDF. There were significant differences among genotypes for the traits evaluated, with a predominance of dominance gene effect. Based on CGC, the best parents were Taiwan A-144, Vruckwona Africana e Taiwan A-146. The best intersections based on CEC were Taiwan A-144 x Taiwan A-146, Vruckwona Africana x Taiwan A-146, Vruckwona Africana x Mercker S.E.A., Vruckwona Africana x Napier nº2 e Pusa Napier nº2 x Mercker Santa Rita.

HPLC quantification of phenolic content and assessment of ...

African Journals Online (AJOL)

The study was aimed at evaluating the toxicological and antioxidant activities of Antiaris africana Engl. (family Moraceae), that is used in Nigeria and other West Africa countries as a panacea for the treatment of several ailments. The methanolic extract of A. africana (MEA) obtained was analysed for antioxidant activities in ...

Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana) treated with a gonadotropin-releasing hormone (GnRH) vaccine for inducing anoestrus.

Science.gov (United States)

Benavides Valades, Gabriela; Ganswindt, Andre; Annandale, Henry; Schulman, Martin L; Bertschinger, Henk J

2012-08-25

In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH) vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Between May 2009-June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM) on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa) 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP) vaccine for four years (2004-2007). All 12 monitored females (8 treated and 4 controls) showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces) were significantly higher (Pelephants. These results indicate that irregular oestrous cycles occur amongst free-ranging elephants and are not restricted to elephants in captivity. The relationship between ecological conditions and endocrine activity were confirmed. Free-ranging female elephants were observed to not cycle continuously throughout the year in the absence of adult bulls.

Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana treated with a gonadotropin-releasing hormone (GnRH vaccine for inducing anoestrus

Directory of Open Access Journals (Sweden)

Benavides Valades Gabriela

2012-08-01

Full Text Available Abstract Background In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Methods Between May 2009 - June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP vaccine for four years (2004-2007. Results All 12 monitored females (8 treated and 4 controls showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces were significantly higher (P Conclusions The GnRH vaccination protocol failed to induce anoestrus in the treated female elephants. These results indicate that irregular oestrous cycles occur amongst free-ranging elephants and are not restricted to elephants in captivity. The relationship between ecological conditions and endocrine activity were confirmed. Free-ranging female elephants were observed to not cycle continuously throughout the year in the absence of adult bulls.

Evaluation of hypoglycaemic and hypolipidaemic effects of aqueous ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-04

Aug 4, 2008 ... effects of aqueous ethanolic extracts of Treculia africana ... Plasma sugar contents were analyzed from the blood collected from the tail vein at 30, 60 and 120 min intervals .... This measures the body's ability to metabolize carbohydrates and produce .... vation supported the local use of the T. africana and B.

Author Details

African Journals Online (AJOL)

Asiegbu, CP. Vol 10, No 1&2 (2009) - Articles Continuous-flow depulping machine for Treculia Africana Abstract PDF · Vol 10, No 1-2 (2011) - Articles Continuous-Flow Depulping Machine for Treculia Africana Abstract PDF. ISSN: 1596-292X. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for ...

Phylogenetic relationships in the genus Leonardoxa (Leguminosae: Caesalpinioideae) inferred from chloroplast trnL intron and trnL-trnF intergenic spacer sequences.

Science.gov (United States)

Brouat, Carine; Gielly, Ludovic; McKey, Doyle

2001-01-01

The African genus LEONARDOXA: (Leguminosae: Caesalpinioideae) comprises two Congolean species and a group of four mostly allopatric subspecies principally located in Cameroon and clustered together in the L. africana complex. LEONARDOXA: provides a good opportunity to investigate the evolutionary history of ant-plant mutualisms, as it exhibits various grades of ant-plant interactions from diffuse to obligate and symbiotic associations. We present in this paper the first molecular phylogenetic study of this genus. We sequenced both the chloroplast DNA trnL intron (677 aligned base pairs [bp]) and trnL-trnF intergene spacer (598 aligned bp). Inferred phylogenetic relationships suggested first that the genus is paraphyletic. The L. africana complex is clearly separated from the two Congolean species, and the integrity of the genus is thus in question. In the L. africana complex, our data showed a lack of congruence between clades suggested by morphological and chloroplast characters. This, and the low level of molecular divergence found between subspecies, suggests gene flow and introgressive events in the L. africana complex.

The in-vitro antimicrobial activities of some medicinal plants from Cameroon.

Science.gov (United States)

Gangoué-Piéboji, J; Pegnyemb, D E; Niyitegeka, D; Nsangou, A; Eze, N; Minyem, C; Mbing, J Ngo; Ngassam, P; Tih, R Ghogomu; Sodengam, B L; Bodo, B

2006-04-01

The antimicrobial activities of 10 plant species (Voacanga africana, Crepis cameroonica, Plagiostyles africana, Crotalaria retusa, Mammea africana, Lophira lanceolata, Ochna afzelii, Ouratea elongata, Ou. flava and Ou. sulcata), each of which is currently used in the traditional medicine of Cameroon, were investigated in vitro. The activities of a methanol extract of each plant were tested, in disc-diffusion assays, against 37 reference or laboratory strains of seven species of microorganism (Staphylococcus aureus, S. epidermidis, Enterococcus hirae, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans). The minimal inhibitory concentrations of each extract were then estimated, against each of the more susceptible microorganisms (i.e. those giving an inhibition zone measuring at least 9 mm in diameter in the disc-diffusion assays), by agar dilution. Although, in the disc-diffusion assays, each of the 10 methanol extracts investigated displayed some degree of antimicrobial activity against at least one species of microorganism, no activity against the Gram-negative bacteria (Es. coli, K. pneumoniae and Ps. aeruginosa) was observed. The extract with the greatest antimicrobial activity was that of Pl. africana (Euphorbiaceae).

In Vitro Antibacterial Potential of Extracts of Sterculia africana, Acacia sieberiana, and Cassia abbreviata ssp. abbreviata Used by Yellow Baboons (Papio cynocephalus for Possible Self-Medication in Mikumi National Park, Tanzania

Directory of Open Access Journals (Sweden)

Irene Kirabo

2018-01-01

Full Text Available The animals in general and nonhuman primates in particular self-medication has been widely reported; however, little is still known about the pharmacological activity of the extracts present in their daily diet. The in vitro antibacterial activity of the stem, root bark, and leaf extracts of three selected plants on which yellow baboons feed in unusual manner in Mikumi National Park, Tanzania, was evaluated. Crude plant extracts were tested against Gram positive and Gram negative bacteria of medical and veterinary importance employing a modified agar well diffusion method and Minimum Inhibitory Concentration (MIC technique. The lowest MIC value for Gram positive strains was 0.31 mg/ml demonstrated by Cassia abbreviata ssp. abbreviata against Staphylococcus aureus (ATCC 25923. The highest susceptibility to the ethanol plant extracts was exhibited by Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus, examples of microbes that affect both human and nonhuman primates. These findings demonstrate that the plant extracts from Sterculia africana, Acacia sieberiana, and Cassia abbreviata ssp. abbreviata have antibacterial activity and may be used as feed for their prophylactic benefits. Remarkably, the lowest MIC of 0.16 mg/ml was only 16-fold weaker than Gentamicin, a standard drug.

QUAFRINOIC ACIDS: TWO NEW TRITERPENIODS FROM ...

African Journals Online (AJOL)

From the stem bark of Quassia africana, two new triterpenoids with the ursolic acid skeleton, characterized as 3-oxo-urs-12-en-27a, 28di-oic acid and its dihydro derivative, 3β-urs-12-en-27α, 28di-oic acid have been isolated. The structures were determined using spectroscopic techniques. KEY WORDS: Quassia africana; ...

Development and evaluation of a threshing machine for Prosopis ...

African Journals Online (AJOL)

A decorticating machine for Prosopis Africana was developed, tested and evaluated. Prosopis Africana is popular in the Sub-Saharan Africa, with all the parts of the tree useful for medicinal purposes. This study focuses on the threshing of the pod to obtain the seed, which is the most widely used of the parts of the Prosopis ...

Large herbivores that strive mightily but eat and drink as friends

NARCIS (Netherlands)

Boer, de W.F.; Prins, H.H.T.

1990-01-01

Grazing in patches of Cynodon dactylon and of Sporobolus spicatus by four large herbivores, and the interaction between these sedentary herbivores was studied in Lake Manyara National Park, northern Tanzania. The herbivores were the African buffalo, Syncerus caffer; the African elephan, Loxodonta

821-IJBCS-Article-Dr Fatimata Niang-Diop

African Journals Online (AJOL)

DR GATSING

Contraintes de régénération naturelle de Prosopis africana : facteurs affectant la germination des graines ... Prosopis africana fait partie des espèces ligneuses confrontées à un problème de régénération naturelle dans la forêt de Fathala. In situ, une ..... et les expose à certains risques tels que l'infestation et la prédation ...

Using genetic profiles of African forest elephants to infer population structure, movements, and habitat use in a conservation and development landscape in Gabon

NARCIS (Netherlands)

Eggert, L. S.; Buij, R.; Lee, M. E.; Campbell, P.; Dallmeier, F.; Fleischer, R. C.; Alonso, A.; Maldonado, J. E.

Conservation of wide-ranging species, such as the African forest elephant (Loxodonta cyclotis), depends on fully protected areas and multiple-use areas (MUA) that provide habitat connectivity. In the Gamba Complex of Protected Areas in Gabon, which includes 2 national parks separated by a MUA

using genetic profiles of african forest elephants to infer population structure, movements, and habitat use in a conservation and development landscape in gabon

NARCIS (Netherlands)

Eggert, L.S.; Buij, R.; Lee, M.E.; Campbell, P.; Dallmeier, F.; Fleischer, R.C.; Alonso, A.; Maldonado, J.

2014-01-01

Conservation of wide-ranging species, such as the African forest elephant (Loxodonta cyclotis), depends on fully protected areas and multiple-use areas (MUA) that provide habitat connectivity. In the Gamba Complex of Protected Areas in Gabon, which includes 2 national parks separated by a MUA

Resolution of the type material of the Asian elephant, Elephas maximus Linnaeus, 1758 (Proboscidea, Elephantidae)

DEFF Research Database (Denmark)

Cappellini, Enrico; Gentry, A.; Palkopoulou, E.

2014-01-01

.maximus, a complete foetus preserved in ethanol, is actually an African elephant, genus Loxodonta. We further discovered that an additional E.maximus syntype, mentioned in a description by John Ray (1693) cited by Linnaeus, has been preserved as an almost complete skeleton at the Natural History Museum...

COMADRE: a global data base of animal demography.

Science.gov (United States)

Salguero-Gómez, Roberto; Jones, Owen R; Archer, C Ruth; Bein, Christoph; de Buhr, Hendrik; Farack, Claudia; Gottschalk, Fränce; Hartmann, Alexander; Henning, Anne; Hoppe, Gabriel; Römer, Gesa; Ruoff, Tara; Sommer, Veronika; Wille, Julia; Voigt, Jakob; Zeh, Stefan; Vieregg, Dirk; Buckley, Yvonne M; Che-Castaldo, Judy; Hodgson, David; Scheuerlein, Alexander; Caswell, Hal; Vaupel, James W

2016-03-01

The open-data scientific philosophy is being widely adopted and proving to promote considerable progress in ecology and evolution. Open-data global data bases now exist on animal migration, species distribution, conservation status, etc. However, a gap exists for data on population dynamics spanning the rich diversity of the animal kingdom world-wide. This information is fundamental to our understanding of the conditions that have shaped variation in animal life histories and their relationships with the environment, as well as the determinants of invasion and extinction. Matrix population models (MPMs) are among the most widely used demographic tools by animal ecologists. MPMs project population dynamics based on the reproduction, survival and development of individuals in a population over their life cycle. The outputs from MPMs have direct biological interpretations, facilitating comparisons among animal species as different as Caenorhabditis elegans, Loxodonta africana and Homo sapiens. Thousands of animal demographic records exist in the form of MPMs, but they are dispersed throughout the literature, rendering comparative analyses difficult. Here, we introduce the COMADRE Animal Matrix Database, an open-data online repository, which in its version 1.0.0 contains data on 345 species world-wide, from 402 studies with a total of 1625 population projection matrices. COMADRE also contains ancillary information (e.g. ecoregion, taxonomy, biogeography, etc.) that facilitates interpretation of the numerous demographic metrics that can be derived from its MPMs. We provide R code to some of these examples. We introduce the COMADRE Animal Matrix Database, a resource for animal demography. Its open-data nature, together with its ancillary information, will facilitate comparative analysis, as will the growing availability of databases focusing on other aspects of the rich animal diversity, and tools to query and combine them. Through future frequent updates of COMADRE, and

Recumbence Behavior in Zoo Elephants: Determination of Patterns and Frequency of Recumbent Rest and Associated Environmental and Social Factors.

Directory of Open Access Journals (Sweden)

Matthew R Holdgate

Full Text Available Resting behaviors are an essential component of animal welfare but have received little attention in zoological research. African savanna elephant (Loxodonta africana and Asian elephant (Elephas maximus rest includes recumbent postures, but no large-scale investigation of African and Asian zoo elephant recumbence has been previously conducted. We used anklets equipped with accelerometers to measure recumbence in 72 adult female African (n = 44 and Asian (n = 28 elephants housed in 40 North American zoos. We collected 344 days of data and determined associations between recumbence and social, housing, management, and demographic factors. African elephants were recumbent less (2.1 hours/day, S.D. = 1.1 than Asian elephants (3.2 hours/day, S.D. = 1.5; P < 0.001. Nearly one-third of elephants were non-recumbent on at least one night, suggesting this is a common behavior. Multi-variable regression models for each species showed that substrate, space, and social variables had the strongest associations with recumbence. In the African model, elephants who spent any amount of time housed on all-hard substrate were recumbent 0.6 hours less per day than those who were never on all-hard substrate, and elephants who experienced an additional acre of outdoor space at night increased their recumbence by 0.48 hours per day. In the Asian model, elephants who spent any amount of time housed on all-soft substrate were recumbent 1.1 hours more per day more than those who were never on all-soft substrate, and elephants who spent any amount of time housed alone were recumbent 0.77 hours more per day than elephants who were never housed alone. Our results draw attention to the significant interspecific difference in the amount of recumbent rest and in the factors affecting recumbence; however, in both species, the influence of flooring substrate is notably important to recumbent rest, and by extension, zoo elephant welfare.

Systematic review on the conservation genetics of African savannah elephants.

Science.gov (United States)

Zacarias, Daniel; Bini, Luis Mauricio; Loyola, Rafael

2016-01-01

In this paper we review the conservation genetics of African savannah elephants, aiming to understand the spatio-temporal research trends and their underlying factors. As such, we explore three questions associated to the conservation genetics and molecular ecology of these elephants: (1) what are the research trends concerning the conservation genetics of Loxodonta africana ? (2) Do richer countries conduct more research on the genetics of African elephants? (3) Which attributes influence where scholars conduct their research? We examined available peer-reviewed publications from 1993 to 2014 in complementary online databases, including the ISI/Web of Science (WoS), Scopus and Google Scholar (GS), and searched for publications in scientific journals as well as in the reference section of these publications. We analyzed the annual trend of publications in this field of research, including the number of authors, levels of collaboration among authors, year of publication, publishing journal and the countries from where genetic samples were collected. Additionally, we identified main research clusters, authors, and institutional collaborations, based on co-citation and co-occurrence networks. We found that during the study period there was a positive trend in the number of publications and a reduction in the number of authors per paper. Twenty-five countries contributed, with the majority of publications authored by researchers in the USA, Kenya and South Africa. The majority of samples were collected in Kenya, Tanzania and South Africa. Research outputs are associated with the existence of long-term conservation/research projects and research potential as measured by the literacy rate and the number of higher education institutions in a country. Five research clusters were identified, focusing on the origin and evolution of the species, methodological issues and the relatedness among elephant species. Research in this field should be expanded to additional countries

Host specificity and basic ecology of Mammomonogamus (Nematoda, Syngamidae) from lowland gorillas and forest elephants in Central African Republic

Czech Academy of Sciences Publication Activity Database

Červená, B.; Vallo, P.; Pafčo, B.; Jirků-Pomajbíková, Kateřina; Jirků, Miloslav; Petrželková, Klára Judita; Todd, A.; Turkalo, A. K.; Modrý, David

2017-01-01

Roč. 144, č. 8 (2017), s. 1016-1025 ISSN 0031-1820 Institutional support: RVO:60077344 Keywords : 18S rDNA * cox1 * Dzanga-Sangha Protected Areas * haplotype * interspecies transmission * Loxodonta cyclotis * Gorilla gorilla gorilla Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.713, year: 2016

Explicación de las disparidades raciales en la salud neonatal en Brasil

Directory of Open Access Journals (Sweden)

Kwame A. Nyarko

2014-04-01

Full Text Available OBJETIVOS: Buscamos cuantificar la manera en que los efectos socioeconómicos, demográficos, geográficos y de atención de salud explican las disparidades raciales en las tasas de bajo peso al nacer y prematuridad en Brasil. MÉTODOS: Utilizamos una muestra de 8 949 niños nacidos entre 1995 y el 2009 en 15 ciudades y 7 provincias de Brasil. Nos centramos en las disparidades en la prevalencia de bajo peso al nacer (< 2 500 g y prematuridad (< 37 semanas de gestación en recién nacidos de ascendencia solo africana o mezclada con otras ascendencias y de ascendencia solo europea. Usamos un modelo de descomposición para cuantificar la contribución de los factores conceptualmente pertinentes a esas disparidades. RESULTADOS: El modelo permitió explicar entre 45% y 94% de las disparidades en cuanto al bajo peso al nacer y entre 64% y 94% de las disparidades en cuanto a la prematuridad entre los grupos de ascendencia africana y de ascendencia europea. Las diferencias en el uso de atención prenatal y en la ubicación geográfica fueron los factores más importantes, seguidos por las diferencias socioeconómicas. El modelo permitió explicar la mayoría de las disparidades en los recién nacidos de ascendencia africana mezclada y parte de las disparidades en los de ascendencia solo africana. CONCLUSIONES: En las políticas públicas para mejorar la salud infantil se deben abordar las diferencias en cuanto a la atención prenatal y la ubicación geográfica a fin de reducir las disparidades en materia de salud entre los recién nacidos de ascendencia africana y los de ascendencia europea en Brasil.

Evolution of finger millet: evidence from random amplified polymorphic DNA.

Science.gov (United States)

Hilu, K W

1995-04-01

Finger millet (Eleusine coracana ssp. coracana) is an annual tetraploid member of a predominantly African genus. The crop is believed to have been domesticated from the tetraploid E. coracana ssp. africana. Cytogenetic and isozyme data point to the allopolyploid nature of the species and molecular information has shown E. indica to be one of the genomic donors. A recent isozyme study questioned the proposed phylogenetic relationship between finger millet and its direct ancestor subspecies africana. An approach using random amplified polymorphic DNA (RAPD) was employed in this study to examine genetic diversity and to evaluate hypotheses concerning the evolution of domesticated and wild annual species of Eleusine. Unlike previous molecular approaches, the RAPD study revealed genetic diversity in the crop. The pattern of genetic variation was loosely correlated to geographic distribution. The allotetraploid nature of the crop was confirmed and molecular markers that can possibly identify the other genomic donor were proposed. Genotypes of subspecies africana did not group closely with those of the crop but showed higher affinities to E. indica, reflecting the pattern of similarity revealed by the isozyme study. The multiple origin of subspecies africana could explain the discrepancy between the isozyme-RAPD evidence and previous information. The RAPD study showed the close genetic affinity of E. tristachya to the E. coracana--E. indica group and understood the distinctness of E. multiflora.

La literatura autobiográfica africana escrita por mujeres: contratos de lectura. The African autobiographical literature written by women: reading contracts

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Elena Cuasante

2014-11-01

Full Text Available El presente trabajo parte de la idea de que el estudio de los géneros literarios exige considerar no solo los rasgos formales del texto, sino también las diferentes modalidades contractuales susceptibles de aparecer en su recepción. Dicho de otro modo, un texto solo se integra en un género de escritura concreto cuando es reconocido como tal por parte del destinatario, operación que, aunque comporta ciertos conocimientos teóricos, es de carácter pragmático. El lector será quien, de manera individual, y apoyándose en todos los datos que tiene a su alcance, decida el modo de lectura que le resulta más apropiado. En este trabajo intentaremos ilustrar este proceso analizando un corpus de textos autobiográficos pertenecientes a la primera generación de escritoras africanas de expresión francesa, elección que pretende satisfacer al mismo tiempo los criterios de cohesión (todas las escritoras comparten un mismo contexto socio-histórico y de representatividad, pues pensamos que nuestras conclusiones son trasladables a otros corpus similares, en particular a los que se derivan de las denominadas “literaturas emergentes”. This paper is based on the idea that the study of literary genres needs to take into consideration not only the formal features of the text but also the different contractual modalities which might appear in their reception. In other words, a text is only part of a specific writing genre when it is recognized as such by the addressee, operation which, although entailing certain theoretical knowledge, has a pragmatic character. It will be the reader who, individually and relying on all the data at his disposal, will decide the reading process which he finds more appropriate. In this paper we will try to show this process by analysing a corpus of autobiographical texts written by the first generation of African French-speaking female writers, a choice which aims to meet at the same time the criteria of cohesion (all the

Mutualism, hybrid inviability and speciation in a tropical ant-plant.

Science.gov (United States)

Léotard, G; Saltmarsh, A; Kjellberg, F; McKey, D

2008-07-01

Although biotic interactions are particularly intricate in the tropics, few studies have examined whether divergent adaptations to biotic interactions lead to speciation in tropical organisms. Ant-plant mutualisms are widespread in the tropics. Within Leonardoxa africana, two subspecies present contrasting defences against herbivores. Young leaves of subsp. africana are defended by mutualistic ants, whereas subsp. gracilicaulis satiates herbivores by synchronized leaf production. Subsp. africana possesses hollow internodes and many large foliar nectaries, housing and feeding ants. We detected no genetic introgression between the two subspecies in the contact zone between them. F1 hybrids were present. They were intermediate in phenotype, expressing reduced, nonfunctional but costly myrmecophilic traits. However, they suffered more herbivory than their parents. Hybrids remained small, failing to reach reproductive size, probably due to their maladapted defence phenotype. Hence, there could be a direct link between adaptation to mutualism and reproductive isolation: biotic interactions could be a driver of tropical diversity.

Indications of progressive desiccation of the Transvaal Lowveld over the past 100 years, and implications for the water stabilization programme in the Kruger National Park

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U. De V. Pienaar

1985-11-01

Full Text Available All available rainfall statistics recorded for the Kruger National Park area since 1907, coupled with an analysis of all the historical climatological data on hand, appear to confirm the quasi-twenty-year rainfall oscillation in precipitation pattern for the summer rainfall area. This was first pointed out by Tyson & Dyer (1975. The dendrochronological data obtained by Hall (1976 from a study of growth rings of a very old yellowwood tree (Podocarpus falcatus in Natal, also appear to indicate a superimposed, long-term (80-100 years pattern of alternate below- average and above-average rainfall periods. The historical data relating to climate in the park, during the past century or two, seem to bear out such a pattern. If this can be confirmed, it will be an enormous aid not only in wildlife-management planning, but also to agriculturists, demographic planners and others. It would appear that the long, relatively dry rainfall period of 1860-1970, with its concomitant progressive desiccation of the @ area in question, has passed over into the next aboveverage rainfall era. This does not mean that there will be no further cataclysmic droughts during future rainfall trough periods. It is therefore wise to plan ahead to meet such contingencies. The present water distribution pattern in the park (natural plus artificial water is conspicuously still well below that which pertained, during dry seasons, at the turn of the century, when the Sabi and Shingwedzi game reserves were proclaimed. It is the declared policy of the National Parks Board of Trustees to simulate natural regulating mechanisms as closely as possible. In consequence the artificial water-for-game program is a long way from completion. The large numbers of game animals in the park (including dominant species such as elephant Loxodonta africana and buffalo Syncerus coffer can no longer migrate out of the area to escape natural catastrophes (such as the crippling droughts of 1911-1917, the

Gonçalves, António Custódio: A história revisitada do Kongo e de Angola. Lisboa: Editorial Estampa, 2005

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Rosana Gonçalves

2006-12-01

Full Text Available Antônio Custódio Gonçalves é sociólogo e professor catedrático de Geografia da Universidade do Porto, onde dirige o Centro de Estudos Africanos (CEAUP, coordenando um importante periódico sobre África, a Africana Studia. Há anos debruçado sobre temáticas africanas, António Custódio Gonçalves sintetiza muitas das complexas questões sobre a história do Kongo e Angola nesta publicação.

AFRICAN ART: A STUDY ON THE BELIEFS AND PREFERENCES OF INTERESTED PEOPLE

OpenAIRE

BERNARDO AMADO BAPTISTA DE FIGUEIREDO

2007-01-01

Trata-se de pesquisa qualitativa, realizada por meio de grupos focais e painéis visuais com interessados em objetos de arte africana no Brasil, com o objetivo de levantar crenças e preferências desses indivíduos. O estudo explorou o conceito de arte africana junto a esse público, imagens e emoções associadas a esse conceito, motivos que orientam a preferência por alguns objetos sobre outros e aspectos importantes do valor simbólico e estético dos objetos...

O PRIMITIVISMO NO MODERNISMO

OpenAIRE

Barros, Maria Mirtes dos Santos; Universidade Federal do Maranhão - UFMA

2011-01-01

Este artigo tem como objetivo analisar a ideia de primitivo no modernismo, a partir das obras de dois artistas e a influência da arte primitiva - para Gauguin, o mundo taitiano, para Picasso, a arte africana. Procuraremos ainda estudar as razões que levaram Gauguin a viver parte de sua vida entre os nativos e a representá-los em suas telas, e que levaram Picasso a incluir a arte africana em sua obra "Les Demoiselles d' Avignon".Palavras-chave: Modernismo. Primitivismo. Vanguardas artísticas. ...

Identification of the ``a'' Genome of Finger Millet Using Chloroplast DNA

Science.gov (United States)

Hilu, K. W.

1988-01-01

Finger millet (Eleusine corocana subsp. coracana), an important cereal in East Africa and India, is a tetraploid species with unknown genomic components. A recent cytogenetic study confirmed the direct origin of this millet from the tetraploid E. coracana subsp. africana but questioned Eleusine indica as a genomic donor. Chloroplast (ct) DNA sequence analysis using restriction fragment pattern was used to examine the phylogenetic relationships between E. coracana subsp. coracana (domesticated finger millet), E. coracana subspecies africana (wild finger millet), and E. indica. Eleusine tristachya was included since it is the only other annual diploid species in the genus with a basic chromosome number of x = 9 like finger millet. Eight of the ten restriction endonucleases used had 16 to over 30 restriction sites per genome and were informative. E. coracana subsp. coracana and subsp. africana and E. indica were identical in all the restriction sites surveyed, while the ct genome of E. tristachya differed consistently by at least one mutational event for each restriction enzyme surveyed. This random survey of the ct genomes of these species points out E. indica as one of the genome donors (maternal genome donor) of domesticated finger millet contrary to a previous cytogenetic study. The data also substantiate E. coracana subsp. africana as the progenitor of domesticated finger millet. The disparity between the cytogenetic and the molecular approaches is discussed in light of the problems associated with chromosome pairing and polyploidy. PMID:8608927

Identification of the "A" genome of finger millet using chloroplast DNA.

Science.gov (United States)

Hilu, K W

1988-01-01

Finger millet (Eleusine corocana subsp. coracana), an important cereal in East Africa and India, is a tetraploid species with unknown genomic components. A recent cytogenetic study confirmed the direct origin of this millet from the tetraploid E. coracana subsp. africana but questioned Eleusine indica as a genomic donor. Chloroplast (ct) DNA sequence analysis using restriction fragment pattern was used to examine the phylogenetic relationships between E. coracana subsp. coracana (domesticated finger millet), E. coracana subspecies africana (wild finger millet), and E. indica. Eleusine tristachya was included since it is the only other annual diploid species in the genus with a basic chromosome number of x = 9 like finger millet. Eight of the ten restriction endonucleases used had 16 to over 30 restriction sites per genome and were informative. E. coracana subsp. coracana and subsp. africana and E. indica were identical in all the restriction sites surveyed, while the ct genome of E, tristachya differed consistently by at least one mutational event for each restriction enzyme surveyed. This random survey of the ct genomes of these species points out E. indica as one of the genome donors (maternal genome donor) of domesticated finger millet contrary to a previous cytogenetic study. The data also substantiate E. coracana subsp. africana as the progenitor of domesticated finger millet. The disparity between the cytogenetic and the molecular approaches is discussed in light of the problems associated with chromosome pairing and polyploidy.

Characterization of the interaction between 3-Oxotabersonine and two serum albumins by using spectroscopic techniques

International Nuclear Information System (INIS)

Wang, Qing; Yan, Jin; He, Jiawei; Bai, Keke; Li, Hui

2013-01-01

3-Oxotabersonine (OTAB) is a component of Voacanga africana, which is a type of traditional drug in Africa widely used for treating diseases. This study examines the interaction of OTAB with bovine serum albumin (BSA) and human serum albumin (HSA) under physiological conditions. The interaction between OTAB and BSA/HSA was investigated using fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy, and molecular modeling under simulated physiological conditions. The experimental results confirm that the quenching mechanism is a static quenching process. The binding site number (n) and the apparent binding constant (K) were measured at various temperatures. The thermodynamic parameters, namely, enthalpy change (ΔH) and entropy change (ΔS), were calculated. Furthermore, the structural changes in the serum albumin that affected the OTAB binding were determined using FT-IR. The binding site was assumed to be located in site I of the BSA/HSA (subdomain IIA). -- Highlights: ► Make use of the 3-Oxotabersonine firstly extracted from seeds of Voacanga africana Stapf to study the drug–protein system. ► Use two kinds of similar structure serum albumins to do a comparative study. ► FT-IR was used to study the conformational change of BSA and HSA. ► Use the BSA and HSA structure obtained from the Brookhaven Protein Data Bank for molecular docking

Characterization of the interaction between 3-Oxotabersonine and two serum albumins by using spectroscopic techniques

Energy Technology Data Exchange (ETDEWEB)

Wang, Qing; Yan, Jin; He, Jiawei; Bai, Keke [College of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Li, Hui, E-mail: lihuilab@sina.com [College of Chemical Engineering, Sichuan University, Chengdu 610065 (China)

2013-06-15

3-Oxotabersonine (OTAB) is a component of Voacanga africana, which is a type of traditional drug in Africa widely used for treating diseases. This study examines the interaction of OTAB with bovine serum albumin (BSA) and human serum albumin (HSA) under physiological conditions. The interaction between OTAB and BSA/HSA was investigated using fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy, and molecular modeling under simulated physiological conditions. The experimental results confirm that the quenching mechanism is a static quenching process. The binding site number (n) and the apparent binding constant (K) were measured at various temperatures. The thermodynamic parameters, namely, enthalpy change (ΔH) and entropy change (ΔS), were calculated. Furthermore, the structural changes in the serum albumin that affected the OTAB binding were determined using FT-IR. The binding site was assumed to be located in site I of the BSA/HSA (subdomain IIA). -- Highlights: ► Make use of the 3-Oxotabersonine firstly extracted from seeds of Voacanga africana Stapf to study the drug–protein system. ► Use two kinds of similar structure serum albumins to do a comparative study. ► FT-IR was used to study the conformational change of BSA and HSA. ► Use the BSA and HSA structure obtained from the Brookhaven Protein Data Bank for molecular docking.

Host specificity and basic ecology of Mammomonogamus (Nematoda, Syngamidae) from lowland gorillas and forest elephants in Central African Republic

Czech Academy of Sciences Publication Activity Database

Červená, B.; Vallo, Peter; Pafčo, B.; Jirků, K.; Jirků, M.; Petrželková, Klára Judita; Todd, A.; Turkalo, A. K.; Modrý, D.

2017-01-01

Roč. 144, č. 8 (2017), s. 1016-1025 ISSN 0031-1820 R&D Projects: GA ČR GA15-05180S Institutional support: RVO:68081766 Keywords : 18S rDNA * cox1 * Dzanga-Sangha Protected Areas * haplotype * interspecies transmission * Loxodonta cyclotis * Gorilla gorilla gorilla Subject RIV: EG - Zoology OBOR OECD: Parasitology Impact factor: 2.713, year: 2016

PERFORMANCE AND EMISSIONS OF A HEAVY DUTY DIESEL ENGINE FUELLED WITH PALM OIL BIODIESEL AND PREMIUM DIESEL

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HELMER ACEVEDO

2011-01-01

Full Text Available Biodiesel es promocionado como combustible alternativo para sustituir combustibles de origen fósil y reducir emisiones de carbono. Algunos estudios han sido llevados a cabo para estudiar las emisiones de vehículos diesel de baja potencia. Sin embargo, las emisiones sólidas y gaseosas emitidas por vehículos de trabajo operados con biodiesel de palma africana y diesel de bajo contenido de azufre (~ 15 ppm han sido poco estudiadas. El objetivo de este estudio fue determinar el desempeño y emisiones de un motor Diesel Cummins, 4 tiempos, 9.5 litros, 6 cilindros con sistema de inyección "common rail", y sistema de recirculación de gases. El motor desarrolló una menor potencia (10 % cuando fue operado con biodiesel de palma africana. El motor cumplió con la norma ambiental 2004 cuando fue operado con combustible diesel, sin embargo, con biodiesel de palma africana las emisiones de material particulado y los óxidos de nitrógeno estuvieron fuera de norma.

of Spirostachys africana complicated

African Journals Online (AJOL)

C Scott, FCPaed (SA). Department of Paediatrics, Red Cross War Memorial Children's Hospital and University of Cape Town. N P Khumalo, MB ChB, .... Jeung YJ, Lee JY, Oh MJ, Choi DC, Lee BJ. Comparison of the causes and clinical features of drug rash with eosinophilia and systemic symptoms and Stevens-Johnson ...

Esculpir o tempo: arte, educação e ancestralidade entre os Fons, os Iorubás e os Tchokwes

OpenAIRE

Júlio César Boaro

2013-01-01

Esta dissertação aponta para um caminho cuja trajetória é a busca e o entendimento da complexidade da arte e da cultura africana, especialmente da África subsaariana e, dessa forma, contribuir para uma reflexão sobre a formação da cultura brasileira nos seus modos de ser e de pensar, através das características atribuídas aos descendentes de africanos que para o Brasil foram trazidos na condição de escravos. Nosso ponto de partida é a religiosidade de matriz africana reinventada no Brasil, e ...

Valoración ecosistémica a partir del uso de métricas de paisaje aplicando sistemas de información geográfica en cultivos de palma africana

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Claudia Mayelly Ramírez Cano

2016-12-01

Full Text Available La valoración del paisaje es una herramienta que contribuye en los procesos de gestión y planificación mediante la generación de indicadores que permiten caracterizar las condiciones del territorio. En esta investigación se analizaron las métricas de paisaje a partir de: área de la clase (CA, área total del paisaje (TA, porcentaje del área total del paisaje (PLAND, número de parches de la clase (NP y densidad de parches (PD, relación área-perímetro promedio (MPAR, índice de diversidad de Shannon (SDI e índice de equitatividad de Shannon  (SEI y la valoración se realizó con la adaptación metodológica de los autores Paula Másmela y Alejandro Gómez, dicha adaptación permitió discernir sobre las características y calidad del paisaje en el municipio de Puerto Wilches, Santander, Colombia, durante el periodo entre 1987 y 2015.  La valoración paisajística se realizó a partir de imágenes de satélite mediante análisis multitemporal de las coberturas para cuantificar y caracterizar las transformaciones paisajísticas dadas en el territorio. Los resultados obtenidos muestran que en el año 1987 el paisaje era más dinámico, constituido por variedad de coberturas y ecosistemas; mientras en 2015 existe una implementación a gran escala del monocultivo de palma africana que rompe con la estructura paisajística, sin embargo, el resultado de calidad visual arrojó clasificación media, que evidencia la importancia de realizar una revisión a fondo sobre las actuales políticas de ordenación del territorio.

Explicación de las disparidades raciales en la salud neonatal en Brasil*

Science.gov (United States)

Nyarko, Kwame A.; López-Camelo, Jorge; Castilla, Eduardo E.; Wehby, George L.

2015-01-01

Objetivos. Buscamos cuantificar la manera en que los efectos socioeconómicos, demográficos, geográficos y de atención de salud explican las disparidades raciales en las tasas de bajo peso al nacer y prematuridad en Brasil. Métodos. Utilizamos una muestra de 8 949 niños nacidos entre 1995 y el 2009 en 15 ciudades y 7 provincias de Brasil. Nos centramos en las disparidades en la prevalencia de bajo peso al nacer (y prematuridad (y de ascendencia solo europea. Usamos un modelo de descomposición para cuantificar la contribución de los factores conceptualmente pertinentes a esas disparidades. Resultados. El modelo permitió explicar entre 45% y 94% de las disparidades en cuanto al bajo peso al nacer y entre 64% y 94% de las disparidades en cuanto a la prematuridad entre los grupos de ascendencia africana y de ascendencia europea. Las diferencias en el uso de atención prenatal y en la ubicación geográfica fueron los factores más importantes, seguidos por las diferencias socioeconómicas. El modelo permitió explicar la mayoría de las disparidades en los recién nacidos de ascendencia africana mezclada y parte de las disparidades en los de ascendencia solo africana. Conclusiones. En las políticas públicas para mejorar la salud infantil se deben abordar las diferencias en cuanto a la atención prenatal y la ubicación geográfica a fin de reducir las disparidades en materia de salud entre los recién nacidos de ascendencia africana y los de ascendencia europea en Brasil.

Frequent and seasonally variable sublethal anthrax infections are accompanied by short-lived immunity in an endemic system.

Science.gov (United States)

Cizauskas, Carrie A; Bellan, Steven E; Turner, Wendy C; Vance, Russell E; Getz, Wayne M

2014-09-01

Few studies have examined host-pathogen interactions in wildlife from an immunological perspective, particularly in the context of seasonal and longitudinal dynamics. In addition, though most ecological immunology studies employ serological antibody assays, endpoint titre determination is usually based on subjective criteria and needs to be made more objective. Despite the fact that anthrax is an ancient and emerging zoonotic infectious disease found world-wide, its natural ecology is not well understood. In particular, little is known about the adaptive immune responses of wild herbivore hosts against Bacillus anthracis. Working in the natural anthrax system of Etosha National Park, Namibia, we collected 154 serum samples from plains zebra (Equus quagga), 21 from springbok (Antidorcas marsupialis) and 45 from African elephants (Loxodonta africana) over 2-3 years, resampling individuals when possible for seasonal and longitudinal comparisons. We used enzyme-linked immunosorbent assays to measure anti-anthrax antibody titres and developed three increasingly conservative models to determine endpoint titres with more rigourous, objective mensuration. Between 52 and 87% of zebra, 0-15% of springbok and 3-52% of elephants had measurable anti-anthrax antibody titres, depending on the model used. While the ability of elephants and springbok to mount anti-anthrax adaptive immune responses is still equivocal, our results indicate that zebra in ENP often survive sublethal anthrax infections, encounter most B. anthracis in the wet season and can partially booster their immunity to B. anthracis. Thus, rather than being solely a lethal disease, anthrax often occurs as a sublethal infection in some susceptible hosts. Though we found that adaptive immunity to anthrax wanes rapidly, subsequent and frequent sublethal B. anthracis infections cause maturation of anti-anthrax immunity. By triggering host immune responses, these common sublethal infections may act as

Beehive fences as a multidimensional conflict-mitigation tool for farmers coexisting with elephants.

Science.gov (United States)

King, Lucy E; Lala, Fredrick; Nzumu, Hesron; Mwambingu, Emmanuel; Douglas-Hamilton, Iain

2017-08-01

Increasing habitat fragmentation and human population growth in Africa has resulted in an escalation in human-elephant conflict between small-scale farmers and free-ranging African elephants (Loxodonta Africana). In 2012 Kenya Wildlife Service (KWS) implemented the national 10-year Conservation and Management Strategy for the Elephant in Kenya, which includes an action aimed at testing whether beehive fences can be used to mitigate human-elephant conflict. From 2012 to 2015, we field-tested the efficacy of beehive fences to protect 10 0.4-ha farms next to Tsavo East National Park from elephants. We hung a series of beehives every 10 m around the boundary of each farm plot. The hives were linked with strong wire. After an initial pilot test with 2 farms, the remaining 8 of 10 beehive fences also contained 2-dimensional dummy hives between real beehives to help reduce the cost of the fence. Each trial plot had a neighboring control plot of the same size within the same farm. Of the 131 beehives deployed 88% were occupied at least once during the 3.5-year trial. Two hundred and fifty-three elephants, predominantly 20-45 years old entered the community farming area, typically during the crop- ripening season. Eighty percent of the elephants that approached the trial farms were kept out of the areas protected by the beehive fences, and elephants that broke a fence were in smaller than average groups. Beehive fences not only kept large groups of elephants from invading the farmland plots but the farmers also benefited socially and financially from the sale of 228 kg of elephant-friendly honey. As news of the success of the trial spread, a further 12 farmers requested to join the project, bringing the number of beehive fence protected farms to 22 and beehives to 297. This demonstrates positive adoption of beehive fences as a community mitigation tool. Understanding the response of elephants to the beehive fences, the seasonality of crop raiding and fence breaking, and the

Systematic review on the conservation genetics of African savannah elephants

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Daniel Zacarias

2016-10-01

Full Text Available Background In this paper we review the conservation genetics of African savannah elephants, aiming to understand the spatio-temporal research trends and their underlying factors. As such, we explore three questions associated to the conservation genetics and molecular ecology of these elephants: (1 what are the research trends concerning the conservation genetics of Loxodonta africana? (2 Do richer countries conduct more research on the genetics of African elephants? (3 Which attributes influence where scholars conduct their research? Materials and Methods We examined available peer-reviewed publications from 1993 to 2014 in complementary online databases, including the ISI/Web of Science (WoS, Scopus and Google Scholar (GS, and searched for publications in scientific journals as well as in the reference section of these publications. We analyzed the annual trend of publications in this field of research, including the number of authors, levels of collaboration among authors, year of publication, publishing journal and the countries from where genetic samples were collected. Additionally, we identified main research clusters, authors, and institutional collaborations, based on co-citation and co-occurrence networks. Results We found that during the study period there was a positive trend in the number of publications and a reduction in the number of authors per paper. Twenty-five countries contributed, with the majority of publications authored by researchers in the USA, Kenya and South Africa. The majority of samples were collected in Kenya, Tanzania and South Africa. Research outputs are associated with the existence of long-term conservation/research projects and research potential as measured by the literacy rate and the number of higher education institutions in a country. Five research clusters were identified, focusing on the origin and evolution of the species, methodological issues and the relatedness among elephant species. Conclusions

Construindo vidas na diáspora. Os africanos da cidade do Desterro, Ilha de Santa Catarina (Século XIX

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Claudia Mortari Malavota

2013-06-01

Full Text Available Este artigo tem como objetivo evidenciar e analisar os vínculos parentais estabelecidos por escravos e libertos de procedência africana, sujeitos de diferentes categorias sociais e origens étnicas, no contexto de uma cidade portuária ao Sul do Brasil: Nossa Senhora do Desterro, localizada na Ilha de Santa Catarina. O ponto de partida do artigo é a trajetória de vida, construída a partir de alguns indícios, do africano forro Francisco de Quadros, da africana Catharina, de nação Benguela, e de Francisco de Siqueira, os quais, no contexto do século XIX, estabeleceram relações de solidariedade e vínculos familiares. A partir de suas trajetórias, nossa intenção é descortinar outras inúmeras experiências de vida das populações de origem africana na cidade. Partimos do princípio de que os estabelecimentos de vínculos parentais constituem, num contexto escravista, uma maneira de criar esperanças, de possibilitar a sobrevivência e de reinventar as identidades. Os africanos, ao criar seus vínculos familiares, conferiram sentido a suas vidas e marcaram de forma significativa o espaço social em que viviam.

As “Ticas” de “Matema” de um povo africano: Um exercício para sala de aula brasileira.

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Eliane Costa Santos

2008-08-01

Full Text Available Este artigo tem como foco central apontar uma das alternativas para a introdução da cultura africana numa sala de aula de matemática – concorrendo para a transformação deste espaço formal de uma sala de aula, um espaço no qual a cultura está entrelaçada aos saberes escolares por meio da transdisciplinaridade da etnomatemática. A relação que permeia pode ser delineada de como a cultura africana, por meio da representatividade dos fazeres dos teares africanos Kente pode contribuir com os processos de ensino e aprendizagem em uma sala de aula de matemática. As tramas estão por meio do referencial teórico de Stuart Hall sobre cultura e multiculturalismo; D’Ambrósio sobre transdisciplinaridade e etnomatemática; Dennis sobre tecido Kente e os tecelões de Gana com as tecnologias do tear Kente. Para uma compreensão geral localizamos Gana no Continente Africano, citamos o mitos do tear e por fim apresentamos uma proposta de como exercitar uma relação transcultural a partir do saber fazer da cultura Africana em uma sala de aula de matemática no Brasil.

Using camera traps and digital video to investigate the impact of Aethina tumida pest on honey bee (Apis mellifera adansonii) reproduction and ability to keep away elephants (Loxodonta africana cyclotis) in Gamba, Gabon

OpenAIRE

Steeve Ngama; Lisa Korte; Mireille Johnson; Jérôme Bindelle; Auguste Ndoutoume Ndong; Cédric Vermeulen

2018-01-01

Bees and elephant interactions are the core of a conservation curiosity since it has been demonstrated that bees, one of the smallest domesticated animals, can keep away elephants, the largest terrestrial animals. Yet, insects' parasites can impact the fitness and activity of the bees. Since their activity is critical to the repellent ability against elephants, this study assessed the impact of small hive beetles (Aethina tumida) on bee (Apis mellifera adansonii) reproduction and ability to k...

Evaluation of hypoglycaemic and hypolipidaemic effects of aqueous ...

African Journals Online (AJOL)

Evaluation of hypoglycaemic and hypolipidaemic effects of aqueous ethanolic extracts of Treculia africana Decne and Bryophyllum pinnatum,/i> Lam. and their mixture on streptozotocin (STZ)-induced diabetic rats.

Intricate Entanglement: The ICC and the Pursuit of Peace ...

African Journals Online (AJOL)

Professor of Political Science and International Relations, Africana Studies and ...... in a larger normative political project, beginning with the emergence of ... investigate potential crimes, undercuts the latter's investigatory prerogatives.

Phytochemical evaluation and antibacterial profile of Treculia ...

African Journals Online (AJOL)

STORAGESEVER

2008-05-16

May 16, 2008 ... Treculia africana Decne bark extract on gastrointestinal ... 2Department of Pharmaceutics and Pharmaceutical Technology, ... presence of steroidal saponin glycosides as the major component, anthraquinone glycoside and.

Chemical, Functional and Organoleptic Evaluation of African Breadfruit

African Journals Online (AJOL)

African breadfruit (Treculia africana Decne) seeds were parboiled and their kernels dried ... age were evaluated. .... macular degeneration, and cataract formation ... Heat treatment increased water ab- ..... prevention of cardiovascular disease.

ÁFRICA/BRASIL: corpos, tempos e histórias silenciadasAFRICA/BRAZIL: bodies, time and silenced histories

Directory of Open Access Journals (Sweden)

Maria Antonieta Antonacci

2009-06-01

Full Text Available Na perspectiva que história é cultura, questões abordadas neste ensaio articulam-se à reivindicação fundamental de incorporações de saberes e poderes de tradições orais de culturas africanas e afro-brasileiras em nossos debates e possíveis construções de argumentações históricas relacionadas à História da África, e a culturas africanas e afro-brasileiras entre nós. Tentando acompanhar movimentos históricos de confrontações, negociações e injunções entre saberes locais e projetos globais, procuramos enfrentar armadilhas da construção e projeção de dominâncias eurocêntricas.

Original Research Original Research

African Journals Online (AJOL)

RAGHAVENDRA

building materials; firewood, income generating activities, energy resources; wildlife .... management practices and threats to the wetlands and evaluate the impact of wetland .... macrostachyus, Erythrina brucei, and Cordia africana are under ...

Traços da religiosidade africana no carnaval carioca (Traces of African religiosity in carioca carnival - DOI: 10.5752/P.2175-5841.2013v11n29p53

Directory of Open Access Journals (Sweden)

José Geraldo Rocha

2013-03-01

Full Text Available As discussões a respeito do sagrado na contemporaneidade têm ganhado relevância ao considerarmos as novas perspectivas que se abrem com a inclusão de alguns temas relativos à diversidade cultural e religiosa na sociedade brasileira. Cada dia é perceptível o crescente espaço que o sagrado ocupa na vida cotidiana das pessoas comuns. A presença do sagrado no cotidiano da cultura brasileira é uma marca que realça um relevante aspecto da identidade nacional. A cultura brasileira é uma cultura plural. Para além das matrizes indígenas e européias, existe uma grande variedade cultural no âmbito da africanidade. O presente artigo objetiva analisar como esse elemento sagrado de caráter afro-brasileiro aparece nos enredos das escolas de samba do Rio de Janeiro durante os carnavais de 2011 e 2012. Nosso referencial são as letras dos sambas-enredos das escolas dos grupos C, D, e E que desfilam na Intendente Magalhães, subúrbio do rio de Janeiro. Palavras-chave: Religiosidade. Africana. Sagrado. Carnaval. Rio de Janeiro. Abstract The discussions about the sacred in contemporaneity have gained importance in considering new opportunities opening up with the inclusion of issues related to cultural and religious diversity in Brazilian society. It is noticeable the growing space that sacred plays in everyday life of ordinary people. The presence of the sacred in everyday Brazilian culture is a mark that highlights an relevant aspect of national identity. Brazilian culture is a plural culture. In addition to the indigenous and European origin, there is a great cultural variety in the scope of Africanity. This article aims to analyze how this sacred element of Afro-Brazilian characteristic appears in plots of samba schools in Rio de Janeiro during the carnivals of 2011 and 2012. Our references are the lyrics of the samba schools’ plots of groups C, D, and E, which parade on Intendente Magalhães Street, in a suburban area of Rio de Janeiro. Key

jfewr ©2017 - jfewr Publications

African Journals Online (AJOL)

Mark

2017-03-01

Mar 1, 2017 ... Keywords: Prosopis africana, progeny, seed germination, seedling emergence, seeds. INTRODUCTION ... In Nigeria, the tree is found in Nupe, Zamfara,. Kaduna .... already determined were given pre-sowing treatment by ...

Growth of Bacillus cereus isolated from some traditional condiments ...

African Journals Online (AJOL)

Growth of Bacillus cereus isolated from some traditional condiments under different regimens. ... African Journal of Biotechnology ... (fermented Prosopis africana seeds) and identified as B. cereus, B. subtilis, B. pumilus and B. lichenifomis.

'I'm Black and I'm Proud': A Majority Ecological Context Protects Affective Aspects of Black Identity Under Stereotype Threat.

Science.gov (United States)

Oliver, Andre'; Andemeskel, Ghilamichael; King, Carlise R; Wallace, Lyndsey; McDougal, Serie; Monteiro, Kenneth P; Ben-Zeev, Avi

2017-12-01

We provide evidence that stereotype threat, a phenomenon that causes stigmatized individuals to experience group-based evaluative concerns (Steele in Am Psychol 52:613-629, 1997; Whistling Vivaldi and other clues to how stereotypes affect us, W.W. Norton, New York, 2010), impacts affective aspects of Black identity as a function of majority versus minority ecological contexts. Black/African-American students, enrolled in either Africana Studies (Black ecological majority) or Psychology (Black ecological minority), completed private and public regard subscales from the Multidimensional Inventory of Black Identity (Sellers et al. in Pers Soc Psychol Rev 2:18-39, 1998) at baseline (Time 1) and after being randomly assigned to a stereotype threat or no-threat/control condition (Time 2). In threat, participants were introduced to a 'puzzle' task as diagnostic of intellectual abilities, whereas in no-threat the same task was introduced as culture fair, such that people from different racial/ethnic groups had performed similarly on this task in the past. In Psychology, students under threat exhibited a simultaneous decrease and increase in private and public regard, respectively, a pattern shown in the literature to be associated with discrimination-based distress and lesser well-being in Black ecological minority environments. In contrast, Africana Studies students' racial identity under threat remained intact. We discuss the protective effects of Africana Studies on racial identity and implications for educational reform.

Effect of Traditional Processing Techniques on the Nutritional and ...

African Journals Online (AJOL)

Michael Horsfall

Composition of African Bread-Fruit (Treculia africana) Seeds. *IFEOMA I IJEH .... located mainly in the seed coat (Kumar et al, 1979;. Singh ... development and control of some metabolic processes ... (1996). Regulation of selenoprotein gene.

The diets of fish in three south-western Cape estuarine systems

African Journals Online (AJOL)

1988-09-26

Sep 26, 1988 ... Blaber 1978a; Coetzee 1981, 1982a; Coetzee & Pool. 1985), taxonomic ...... mainly the swimming prawn Macropetasma africana, bivalves (Donax spp.) ..... higher energy value of zooplankton relative to other organisms of ...

Field notes of raptors in and around Mertule Mariam, Gojjam ...

African Journals Online (AJOL)

(rise in temperatures at poles) could have some effect on the population sizes and population ... Agricultural activity is extensive, with cultivation up to ... abyssinica, Cordia Africana, Embelia schimpera, Cupressus lusitanica dominate the valley ...

PENTECOSTALES DE ITALIA

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Enzo Pace

2012-06-01

Full Text Available El artículo se refiere al Pentecostalismo en Italia, centrándose en particular en Iglesias Pentecostales africanas. Como los inmigrantes africanos comenzaron a asentarse en la sociedad italiana, allí recrearon o crearon una red de comunidades carismáticas, sobre todo en la parte norte del país. Las iglesias pentecostales proporcionan apoyo espiritual, social y práctico a sus miembros con el fin de que puedan hacer frente los diversos problemas derivados de la condición del migrante en un nuevo país como Italia, monopolizado histórica y socialmente por el catolicismo. Por lo tanto, el objetivo del artículo es mostrar la relación entre el entorno socio-religioso y el impacto de las nuevas Iglesias africanas Pentecostales.

Some aspects of the Seed Germination and Seedling Growth of two Savanna tree Species

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D.A. Agboola

2014-10-01

Full Text Available Studies were made on some aspects of the seed germination and seedling growth of two multipurpose trees. These include the effect of pre sowing treatments, seed sizes and gibberellic acid on the germination of seeds and seedling growth. The tree species include Prosopis africana (Guil & Perr Taub and Dialium guineense (wild. Two seed sizes designated small- size (Ss and Big-size (Bs were identified in the seed. The effect of gibberellic acid (GA3 had a greater significance effect (P < 0.05 on seed germination of both D. guineense and P. africana seeds. The big size seeds had a significant effect (P < 0.05 on the seed germination when compared to the small size seeds. The hydration/dehydration, pre sowing treatments on the seeds did not have any significant effects on germination.

Comportamiento de tres procedencias de Jatropha curcas en el banco de germoplasma de la EEPF ¨Indio Hatuey¨ Performance of three provenances of Jatropha curcas in the germplasm bank of the EEPF ¨Indio Hatuey¨

Directory of Open Access Journals (Sweden)

R Machado

2009-03-01

Full Text Available Se realizó un ensayo con el objetivo de evaluar tres procedencias de Jatropha curcas, en un suelo Ferralítico Rojo lixiviado de la EEPF ¨Indio Hatuey¨, en las fases de vivero, establecimiento y momento de cosecha. Todas las procedencias necesitaron entre 70 y 90 días para alcanzar su máximo de emergencia. La de Cabo Verde (denominada Africana fue la primera en germinar (11,5-24,6% entre los primeros cinco y 25 días y las dos restantes germinaron a los 35 días. A los 160 días después de plantadas, la Africana alcanzó la fenofase de semilla verde; mientras que las dos restantes se encontraban en abotonamiento. La Africana también fue estadísticamente superior en términos de número de hojas, grosor del tallo y altura de las plántulas. No existieron diferencias en la producción de frutos con tres semillas, indicador en el que todas alcanzaron más del 70%. A los 240 días (cosecha se detectó una alta disminución en el número de hojas, pero el menor porcentaje se constató en la Africana (69% con relación al total. El peso de la semilla cosechada en la Africana fue 7,1 veces superior a la procedencia de Las Tunas (medianamente ramificada y 22,4 veces superior a la de Sancti Spiritus (menos ramificada. De acuerdo con los resultados, se destacó por su comportamiento la Africana. Asimismo, se considera importante la introducción de un mayor número de accesiones, así como la realización de estudios sobre la calidad de la semilla.A trial was conducted with the objective of evaluating three provenances of Jatropha curcas on a lixiviated Ferralitic Red soil of the EEPF ¨Indio Hatuey¨, at the nursery, establishment and harvest stages. All the provenances needed between 70 and 90 days to reach their emergence maximum level. The plants from Cape Verde (called African were the first to germinate (11,5-24,6% between the first five and 25 days and the other two germinated 35 days after planting. One hundred and sixty days after

UTILIZATION OF Prosopis afiicana PULP FOR RABBIT FEEDING: 2

African Journals Online (AJOL)

IBB

The formulated diets contained similar crude protein content of 18%. The apparent ... These results indicate that Prosopis africana pulp can completely replace maize in the diets of ... serum albumin were determined by Biuret reactions. (Bush ...

Biochemical profile of cuttings used for in vitro organogenesis of ...

African Journals Online (AJOL)

Biochemical profile of cuttings used for in vitro organogenesis of Prunus africana: An endangered species in Cameroon. JG Nzweundji, N Niemenak, O Oumar, JJ Tsafack, K Konan, L Nyochembeng, C Noumi, DT Nehemie, DO Ndoumou ...

2144-IJBCS-Article-Amsatou Thiam

African Journals Online (AJOL)

hp

par Tamarix senegalensis, P. aculeata, S. senegalensis, Hibiscus asper, Brachiaria ramosa,. Combretum glutinosum et. Spermacoce stachydea. A. nilotica, Cyperus rotundus, Mytragyna inermis, Acacia seyal,. Commiphora africana, Dactyloctenium aegyptium, Zornia glochidiata, Cassia obtusifolia, Sida alba, Enterpogon ...

Department of Wildlife and Ecotourism Manage

African Journals Online (AJOL)

USER

2016-11-22

Nov 22, 2016 ... scattering seeds. In general, the removal offers some feedbacks for wildlife around the ... survey with previous data reveal that some species, such as Actophilornis africana African ..... the survey would have introduced bias as.

Ethnobotanical knowledge and practices of tradi- tional healers in ...

African Journals Online (AJOL)

pus integer N.E.Br (80%), Punica granatum L. (75%) and Cordia africana L. ... to their attributes having wide biological and medicinal activities, high safety margins ..... tory activity and cardiovascular protective effect (Santhosha et al., 2013).

Simulations

CERN Document Server

Ngada, Narcisse

2015-06-15

The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

Modulation of key biochemical markers relevant to stroke by Antiaris ...

African Journals Online (AJOL)

Modulation of key biochemical markers relevant to stroke by Antiaris africana leaf extract following cerebral ischemia/reperfusion injury. Omotayo B. Ilesanmi, Afolabi C. Akinmoladun, Olanrewaju Sam Olayeriju, Ibrahim Olabayode Saliu, M. Tolulope Olaleye, Afolabi A. Akindahunsi ...

Cameroun

African Journals Online (AJOL)

SARAH

30 juin 2014 ... yohimbe, Rauvolfia vomitoria, Solanum lycopersicum,. Solanum nigrum, Solanum tuberosum, Voacanga africana, Voacanga thouarsii, Zingiber officinale. Les espèces exotiques sont : Acanthus montanus,. Ageratum conyzoides, Aloe vera, Allium sativum,. Apium graveolens, Amaranthus hybridus, Ananas.

Biokemistri - Vol 21, No 2 (2009)

African Journals Online (AJOL)

... in a lean black population · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... Linn: Implications for the Management of Obesity and Cardiovascular Diseases ... of Leaves, Stem and Root Barks of Prosopis africana in Laboratory Animals ...

On two new species of Siriella (Mysidacea)

Digital Repository Service at National Institute of Oceanography (India)

Panampunnayil, S.U.

Descriptions of two new mysids, Siriella africana ap. nov. collected from Agulhas Bank and S. intermedia sp. nov. collected from Laccadives are given. The present paper contains observations on two species of mysidacea collected from the Indian...

Repeated evolution of fungal cultivar specificity in independently evolved ant-plant-fungus symbioses.

Science.gov (United States)

Blatrix, Rumsaïs; Debaud, Sarah; Salas-Lopez, Alex; Born, Céline; Benoit, Laure; McKey, Doyle B; Attéké, Christiane; Djiéto-Lordon, Champlain

2013-01-01

Some tropical plant species possess hollow structures (domatia) occupied by ants that protect the plant and in some cases also provide it with nutrients. Most plant-ants tend patches of chaetothyrialean fungi within domatia. In a few systems it has been shown that the ants manure the fungal patches and use them as a food source, indicating agricultural practices. However, the identity of these fungi has been investigated only in a few samples. To examine the specificity and constancy of ant-plant-fungus interactions we characterised the content of fungal patches in an extensive sampling of three ant-plant symbioses (Petalomyrmex phylax/Leonardoxa africana subsp. africana, Aphomomyrmex afer/Leonardoxa africana subsp. letouzeyi and Tetraponera aethiops/Barteria fistulosa) by sequencing the Internal Transcribed Spacers of ribosomal DNA. For each system the content of fungal patches was constant over individuals and populations. Each symbiosis was associated with a specific, dominant, primary fungal taxon, and to a lesser extent, with one or two specific secondary taxa, all of the order Chaetothyriales. A single fungal patch sometimes contained both a primary and a secondary taxon. In one system, two founding queens were found with the primary fungal taxon only, one that was shown in a previous study to be consumed preferentially. Because the different ant-plant symbioses studied have evolved independently, the high specificity and constancy we observed in the composition of the fungal patches have evolved repeatedly. Specificity and constancy also characterize other cases of agriculture by insects.

Mapping of rDNA on the chromosomes of Eleusine species by fluorescence in situ hybridization.

Science.gov (United States)

Bisht, M S; Mukai, Y

2000-12-01

Mapping of rDNA sites on the chromosomes of four diploid and two tetraploid species of Eleusine has provided valuable information on genome relationship between the species. Presence of 18S-5.8S-26S rDNA on the largest pair of the chromosomes, location of 5S rDNA at four sites on two pairs of chromosomes and presence of 18S-5.8S-26S and 5S rDNA at same location on one pair of chromosomes have clearly differentiated E. multiflora from rest of the species of Eleusine. The two tetraploid species, E. coracana and E. africana have the same number of 18S-5.8S-26S and 5S rDNA sites and located at similar position on the chromosomes. Diploid species, E. indica, E. floccifolia and E. tristachya have the same 18S-5.8S-26S sites and location on the chromosomes which also resembled with the two pairs of 18S-5.8S-26S rDNA locations in tetraploid species, E. coracana and E. africana. The 5S rDNA sites on chromosomes of E. indica and E. floccifolia were also comparable to the 5S rDNA sites of E. africana and E. coracana. The similarity of the rDNA sites and their location on chromosomes in the three diploid and two polyploid species also supports the view that genome donors to tetraploid species may be from these diploid species.

Relative lack of regeneration of shade-intolerant canopy species in some South African forests

CSIR Research Space (South Africa)

Midgley, JJ

1995-01-01

Full Text Available Some species such as Celtis Africana, are experiencing relative recruitment bottlenecks, because there are usually fewer recruits [i.e. individuals <20 cm diameter at breast height, (dbh)] than canopy individuals. The species with low recruitment...

EJST V9N2

African Journals Online (AJOL)

The effects of land use types and soil depth on soil properties of Agedit watershed, Northwest. Ethiopia ... are the most widely practiced activities in Ethiopia. (Eyayu Molla et al., .... are Olea europaea L. subsp cuspidata, Cordia africana Lam.

Huellas de las religiones tradicionales del África subsahariana en América Latina y el Caribe

Directory of Open Access Journals (Sweden)

Lazaro Cabrera Thompson

2008-01-01

Full Text Available El artículo explora las religiones tradicionales practicadas por los pueblos ewe-mina, ewe-fon, bantú y yoruba del África subsahariana, antes de abordar las formas como estas prácticas religiosas persisten en el “Nuevo Mundo” tras la llegada forzosa de aquellos esclavizados africanos. Con base en la presencia de estas religiones tradicionales africanas en distintos países latinoamericanos y caribeño, se evidencia un conjunto religioso fusionado por historias, mitos, leyendas, danza, música, etc. de ascendencia africana y se hace un llamado a los/ as investigadores/as, que desde América Latina y el Caribe, indagan sobre las religiones tradicionales yoruba, para que franqueen los límites de Nigeria con el fin de abarcar a toda la diáspora yoruba.

Antibacterial activity of eight medicinal plants against Diarrhoea ...

African Journals Online (AJOL)

The studies involve the phytochemical screening and antibacterial activity of leaf extracts eight medicinal plants. The selected plants were Timarindus indica, Guiera senegalensis, Prosopis africana, Deterium microcarpum, Citrus aurantifolia, Psidium guajava, Acacia nilotica and Momordica charantia. Methanolics and ...

African Health Sciences Vol 9 Special Issue.pmd

African Journals Online (AJOL)

Administrator

This study was carried out to determine the antibacterial activity of plant extracts of Olea africana stem-bark ... that will/or provide novel or lead compounds that may be employed in ..... Dweck, A.C. Article for cosmetics & toiletries magazine.

Phytochemical and anti-microbial activity of methanolic extract of ...

African Journals Online (AJOL)

The antibacterial activity of leaf extracts of Moringa oleifera Lam, Azadirachta indica, Aspilia africana (Pers) C. D. Adams against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus saphrophyticus were determined using agar diffusion method. The minimum inhibitory concentration (MIC) ...

2 AA Ogungbure Internalism in African epistemology pp39-54

African Journals Online (AJOL)

REGINALDS

Yet the life experiences of African people are multi-dimensional, revealing the nature of reality to African ... existence of gods and other spirit beings in African religion. The spiritual ..... “Nickels in the nation sack: Continuity in Africana spiritual.

Phytochemical and anti-microbial activity of methanolic extract of ...

African Journals Online (AJOL)

The antibacterial activity of leaf extracts of Moringa oleifera Lam, Azadirachta indica, Aspilia Africana (Pers) C. D. Adams against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus saphrophyticus were determined using agar diffusion method. The minimum inhibitory concentration (MIC) ...

APPUNTI PASOLINIANI PER UN'ORESTIADE AFRICANA

African Journals Online (AJOL)

User

in versi del 1964, L'uomo di Bandung, in P. P. Pasolini, Bestemmia, a cura di G. Chiarcossi e W. Siti ... aver visitato Bombay, Calcutta e Nuova Delhi, in febbraio i tre amici ..... africani mossi dal vento, nei silenzi sovraumani, nel cieco istinto di.

BIOSORPTION OF LEAD BY AFZELIA AFRICANA

African Journals Online (AJOL)

Dr Kalu 2

2013-08-07

Aug 7, 2013 ... when low concentrations of these heavy metal ions (in the range of 1- 100 ... heavy metals res- ponsible for causing kidney damage, renal disorder, high .... gradually dissociated and the positively charged cadmium ions will ...

A CHAPTER OF EARLY MEDICAL AFRICANA*

African Journals Online (AJOL)

1971-05-08

May 8, 1971 ... each face 252 Rhynland feet long, constructed of earth,. 20 feet in thickness at the base and tapering to 16 feet at the top, 12 feet high. Round the whole ..... cupping was effected by means of the hollow, cut ends of animal horns and blood letting appears to be done. '""".f\\''',(. Fig. 5. A graphic illustration of ...

Activities of selected medicinal plants against multi-drug resistant ...

African Journals Online (AJOL)

The present work was designed to assess the in vitro antibacterial activities of some Cameroonian medicinal plants including Entada abyssinica, Entada africana, Pentaclethra macrophylla, Allexis cauliflora, Anthocleista leibrechtsiana, Carapa procera, Carica papaya and Persea americana against Gram-negative bacteria ...

Trophic ecology of Lepidoptera larvae associated with woody vegetation in a savanna ecosystem

CSIR Research Space (South Africa)

Scholtz, CH

1982-06-01

Full Text Available This study represents a quantitative survey of a Lepidoptera community and deals with the trophic ecology of the 27 species of foliage-feeding Lepidoptera on the eight dominant woody plants in the Burkea africana-Eragrostis pallens savanna...

Antílope

Directory of Open Access Journals (Sweden)

Pedro Anderson Martinho Moçambique

2015-10-01

Full Text Available Essa espécie de antílope só é encontrada em território angolano, sendo assim um símbolo nacional. Segundo a mitologia africana é símbolo de vivacidade, velocidade e beleza - Angola.

Antílope

Directory of Open Access Journals (Sweden)

Pedro Anderson Martinho Moçambique

2011-04-01

Full Text Available Essa espécie de antílope só é encontrada em território angolano, sendo assim um símbolo nacional. Segundo a mitologia africana é símbolo de vivacidade, velocidade e beleza - Angola.

ОЗГ ГИФЛЕГРГ

African Journals Online (AJOL)

USER

2015-04-23

Apr 23, 2015 ... feeding habits of elephants and destruction of O. africana, to establish the relationship between ... living organisms, forms part of the ... it but also developed a better way of .... is a tree with weak stems that break easily.

The benthos of South Lake, St Lucia following a period of stable ...

African Journals Online (AJOL)

Haminea petersi; the gastropod Assiminea sp.; the polychaetes. Marphysa macintoshi, Glycera tridactyla and Dendronereis ar-. boriJera; oligochaetes; nemerteans; the crab Hymenosoma or- bicu/are; the tanaid Apseudes digitalis-, the amphipod Grandi- dierella lignorum; cumaceans and the mysid Mesopodopsis africana.

Furocyst

African Journals Online (AJOL)

Arun Kumar Agnihotri

Bioefficacy of non-edible parts of Punica granatum: From antioxidant, antibacterial to apoptotic inducing ... Neem seed kernel synthesized silver nanoparticles against Anopheles stephensi and Plasmodium falciparum .... In vitro antibacterial, antioxidant and free radical scavenging activities of fractions of Funtumia africana.

Women's Involvement in Non Timber Forest Products Utilization in ...

African Journals Online (AJOL)

Vitellaria paradoxa, Parkia biglobosa and Prosopis africana were more important for food and income while Nauclea latifolia, Khaya senegalensis ranked highest for medicine. Woody plants preferred as fuel wood included; Parkia biglobosa, Brachystegia eurycoma and Bridelia feruginea. Community Forest Programmes ...

APPLICATION OF A POLYSACCHARIDE DERIVED FROM ...

African Journals Online (AJOL)

While Tragacanth was superior to Treculia gum, the latter performed better than sodium carboxymethylcellulose (SCMC) as a sustained release hydrophilic matrix for theophylline hydrate. Key Words: Polysaccharide, Treculia africana, Moreaceae, Hydrophilic matrix, theophylline hydrate and dissolution rate. Nig. J. Nat.

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2014-06-02

Jun 2, 2014 ... activities are also reasons for the reduction of forests in. Ethiopia. The high ... crucial role in tempering the effects of climate and help protect vital water ..... storey is Cordia africana, which shows the plant, has no regeneration ...

Recuperação de matéria seca e composição química de silagens de gramíneas do gênero Cynodon submetidas a períodos de pré-emurchecimento Recovery of dry matter and chemical composition of Cynodon sp. stargrass silage under periods of pre-wilting

Directory of Open Access Journals (Sweden)

João Paulo Souza Quaresma

2010-10-01

Full Text Available Objetivou-se avaliar o efeito de períodos de pré-emurchecimento das gramíneas Estrela- Africana-Branca [Cynodon plectostachyus (K. Schum. Pilg.] e Tifton 85 (Cynodon sp. sobre algumas características de suas silagens. Utilizou-se delineamento inteiramente casualizado com dez tratamentos e três repetições. Os tratamentos foram dispostos em esquema fatorial 2x5, sendo duas gramíneas (Estrela-Africana-Branca e Tifton 85 e cinco períodos de pré-emurchecimento da forragem (0, 1, 2, 3 e 4 h. As gramíneas foram cortadas aos 50 dias de rebrotação e permaneceram ensiladas por 55 dias em silos experimentais. O pré-emurchecimento promoveu aumento no teor de matéria seca da forragem cortada e da silagem das gramíneas Tifton 85 e Estrela Africana Branca. Houve diminuição nos teores de N-amoniacal (N-NH3/N-total da silagem do capim-estrela-africana-branca, a uma taxa de 1,66 unidade percentual por hora de pré-emurchecimento, mas não houve alteração nessa variável da silagem do capim-tifton 85. A silagem do capim-tifton 85 apresentou maior recuperação de matéria seca, maior teor de FDN e menor teor de proteína bruta do que a silagem do capim-estrela-africana-branca. O pH e o teor de FDA das silagens não foram influenciados pelo pré-emurchecimento.The objective of this work was to evaluate the effect of periods of pre-wilting of stargrass [Cynodon plectostachyus (K. Schum. Pilg.] and Tifton 85 bermudagrass (Cynodon sp. on some characteristics of their silage. Arandomized design with ten treatments and three replications was used. The treatments were arranged in a 2x5 factorial, two grasses (stargrass and Tifton 85 and five periods of pre-wilting of forage (0, 1, 2, 3 and 4 h. The grasses were harvested at 50 days regrowth and stored for 55 days in experimental silos. The pre-wilting caused an increase in dry matter content of forage and silage of both, Tifton 85 and stargrass. There was a decrease in the levels of ammonia-N (N-NH3/N

Antihypertensive effects of double the maximum dose of valsartan in African-American patients with type 2 diabetes mellitus and albuminuria

DEFF Research Database (Denmark)

Weir, Matthew R; Hollenberg, Norman K; Zappe, Dion H

2010-01-01

The blood pressure (BP)-lowering response to renin-angiotensin-aldosterone system blockade in hypertensive African-Americans is typically less than in whites. To determine whether higher than conventional doses of renin-angiotensin-aldosterone system blockade can improve BP reduction in African-A...

Effect of Processing on the Elemental Composition of Selected Leafy ...

African Journals Online (AJOL)

The elemental composition of leaves of Vernonia amygdalina, Gnetum africana, Gongronema latifolium and Ocimum gratissimum subjected to different processing methods were investigated. Processing methods employed include oven drying, sun drying, fresh milling, steaming and a combination of these while the mineral ...

Transformative Learning and the Road to Maternal Leadership

Science.gov (United States)

Panton, Rachel

2016-01-01

This study of three Africana (Black women of the Diaspora) holistic health educators shows how their woman-centered learning cultures led them to personal transformation and leadership roles. Understanding their development can inform educational programming and support services for Black women students.

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The ripe fruits of P. africana were collected from the premises of the ... were then set up in an organ bath containing ... observed (Ward and Elsea, 1977; ..... Press p. 46. OKOYE I. E. (1999): Pilot Scale-up. Application of gum from Prosopis.

1761-IJBCS-Article-Cathérine Nicole Doume Doume

African Journals Online (AJOL)

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11-76. Oyekanmi, Funmilayo B. 2011. Bio-ecology of freshwater prawns Macrobrachium vollenhovenii (Herklots, 1857) and. Caridina africana (Kingsley, 1882) at. Asejire Lake and Erin-ijesa waterfalls,. Nigeria. M.Tech. Fisheries Management. Sipauba -Tavares LH. 1998. Limnologia dos Sistemas de Cultivo. Carcinicultura.

Effect of long-term exclusion of fire and herbivory on the soils and ...

African Journals Online (AJOL)

The wettest grassland, Piet Retief Sourveld on a southern aspect, was transformed to a shrubland matrix (mainly Helichrysum splendidum) with tree clumps of forest precursor species (Rhus dentata, Halleria lucida, Myrsine africana, Buddleja salviifolia, Leucosidea ... Ferns benefitted from exclusion of fire and herbivory.

Molecular identification of Azolla invasions in Africa: The Azolla specialist, Stenopelmus rufinasus proves to be an excellent taxonomist

Science.gov (United States)

Biological control of Azolla filiculoides in South Africa with the Azolla specialist Stenopelmus rufinasus has been highly successful. However, field surveys showed that the agent utilized another Azolla species, thought to be the native Azolla pinnata subsp. africana, which contradicted host specif...

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African Journals Online (AJOL)

Items 1 - 50 of 139 ... ... basic density and strength properties of Cordia africana lam. grown ... Vol 78, No 1 (2008), Effect of aspect on distribution pattern of ... Vol 79, No 1 (2009), Energy expenditure and physiological strain of pitsawing activity in ...

Simulators IV

International Nuclear Information System (INIS)

Fairchild, B.T.

1987-01-01

These proceedings contain papers on simulators with artificial intelligence, and the human decision making process; visuals for simulators: human factors, training, and psycho-physical impacts; the role of institutional structure on simulation projects; maintenance trainers for economic value and safety; biomedical simulators for understanding nature, for medical benefits, and the physiological effects of simulators; the mathematical models and numerical techniques that drive today's simulators; and the demography of simulators, with census papers identifying the population of real-time simulator training devices; nuclear reactors

Repeated evolution of fungal cultivar specificity in independently evolved ant-plant-fungus symbioses.

Directory of Open Access Journals (Sweden)

Rumsaïs Blatrix

Full Text Available Some tropical plant species possess hollow structures (domatia occupied by ants that protect the plant and in some cases also provide it with nutrients. Most plant-ants tend patches of chaetothyrialean fungi within domatia. In a few systems it has been shown that the ants manure the fungal patches and use them as a food source, indicating agricultural practices. However, the identity of these fungi has been investigated only in a few samples. To examine the specificity and constancy of ant-plant-fungus interactions we characterised the content of fungal patches in an extensive sampling of three ant-plant symbioses (Petalomyrmex phylax/Leonardoxa africana subsp. africana, Aphomomyrmex afer/Leonardoxa africana subsp. letouzeyi and Tetraponera aethiops/Barteria fistulosa by sequencing the Internal Transcribed Spacers of ribosomal DNA. For each system the content of fungal patches was constant over individuals and populations. Each symbiosis was associated with a specific, dominant, primary fungal taxon, and to a lesser extent, with one or two specific secondary taxa, all of the order Chaetothyriales. A single fungal patch sometimes contained both a primary and a secondary taxon. In one system, two founding queens were found with the primary fungal taxon only, one that was shown in a previous study to be consumed preferentially. Because the different ant-plant symbioses studied have evolved independently, the high specificity and constancy we observed in the composition of the fungal patches have evolved repeatedly. Specificity and constancy also characterize other cases of agriculture by insects.

COCOA: Simulating Observations of Star Cluster Simulations

Science.gov (United States)

Askar, Abbas; Giersz, Mirek; Pych, Wojciech; Dalessandro, Emanuele

2017-03-01

COCOA (Cluster simulatiOn Comparison with ObservAtions) creates idealized mock photometric observations using results from numerical simulations of star cluster evolution. COCOA is able to present the output of realistic numerical simulations of star clusters carried out using Monte Carlo or N-body codes in a way that is useful for direct comparison with photometric observations. The code can simulate optical observations from simulation snapshots in which positions and magnitudes of objects are known. The parameters for simulating the observations can be adjusted to mimic telescopes of various sizes. COCOA also has a photometry pipeline that can use standalone versions of DAOPHOT (ascl:1104.011) and ALLSTAR to produce photometric catalogs for all observed stars.

African Health Sciences Vol 9 Special Issue.pmd

African Journals Online (AJOL)

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Abstract. Background: Current strategies to overcome the global problem of antimicrobial resistance include research in finding new and innovative antimicrobials from plants. This study was carried out to determine the antibacterial activity of plant extracts of Olea africana stem-bark, Psidium guajava leaves, Vernonia ...

In-vitro antibacterial activity of selected medicinal plants from ...

African Journals Online (AJOL)

Background: Current strategies to overcome the global problem of antimicrobial resistance include research in finding new and innovative antimicrobials from plants. This study was carried out to determine the antibacterial activity of plant extracts of Olea africana stem-bark, Psidium guajava leaves, Vernonia amygdalina ...

Degradation properties of wild Adansonia digitata (Baobab) and ...

African Journals Online (AJOL)

The deterioration of Adansonia digitata and Prosopsis africana oils on storage for 140 days was evaluated using chemical and physical parameters. The chemical parameters evaluated included peroxide value (PV), iodine value (IV), percentage free fatty acids (%FFA), and saponification value (SV). The physical ...

Larvicidal properties of three plants on Anopheles gambiae ...

African Journals Online (AJOL)

No larvae exposed to Q. africana developed into pupae while development was also curtailed when exposed to K. senegalensis and L. multiflora extracts. Larvicidal activity was concentration dependent. These plants could be sources of botanical insecticides for malarial control. Journal of Pharmacy and Bioresources, Vol.

Revision of the genus Parzaommomyia Girault (Hymenoptera: Eulophidae), with taxonomic notes on related genera

NARCIS (Netherlands)

Gumovsky, A.; Ubaidillah, R.

2002-01-01

The eulophid genus Parzaommomyia Girault, 1915, is revised and redefined. Five new species are described and illustrated: P. sulensis spec. nov. from Sulawesi and West Malaysia, P. africana spec. nov. from Nigeria, P. crassicornis spec. nov. from Sulawesi, New Guinea and China, P. achterbergi spec.

Creolising Political Identity and Social Scientific Method

African Journals Online (AJOL)

2014-06-16

Jun 16, 2014 ... *Associate Professor of Political Science and Africana Studies. ... it therefore operated in multiple languages and insisted that theoretical work is necessarily .... antislavery organisations and of the Haitian Revolution offer a good ..... for consideration is its disposition toward the nature of symbolic life. The.

Trypanocidal activity of the aqueous leave extract of Holarrhena ...

African Journals Online (AJOL)

This study evaluated the trypanocidal activity of aqueous extracts of leaves of young Holarrhena africana. The trypanocidal activity was evaluated by treatment of mice infected with Trypanosoma brucei brucei at the peak of infection. The aqueous extract was administered intraperitoneally for 5 consecutive days with varied ...

Length-weight relationships of five fish species in Epe lagoon, Nigeria

African Journals Online (AJOL)

The fishes (Clarias gariepinus (Burch), Illisha africana Bloch), Chrysichthys nigrodigitatus (Lacepede), Chrysichthys walkeri (Gunther) and Ethmalosa fimbriata (Bowdich)) were obtained from fish landing site at Epe market from November 2001 to October 2002, and January to December 2003. The parameters a and b of the ...

Population Structure and Diversity in Finger Millet (Eleusine coracana) Germplasm.

Science.gov (United States)

A genotypic analysis of 79 finger millet accessions (E. coracana subsp. coracana) from 11 African and 5 Asian countries, plus 14 wild E. coracana subsp. africana lines collected in Uganda and Kenya was conducted with 45 SSR markers distributed across the finger millet genome. Phylogenetic and popula...

Variability in estuarine water temperature gradients and influence on ...

African Journals Online (AJOL)

Structure and variability of water temperature gradients and potential influence on distribution of two tropical zooplankters (the mysid Mesopodopsis africana and the copepod Acartia natalensis) and their temperate congenerics (M. wooldridgei and A. longipatella) was investigated over a 10-year period in the Mgazi Estuary, ...

Tamarix minoa (Tamaricaceae), a new species from the island of Crete (Greece) based on morphological and plastid molecular sequence data

Science.gov (United States)

Tamarix minoa is described from material collected on the S Aegean island of Crete (Kriti), Greece. A morphological comparison with the species considered to be closest, T. africana and T. hampeana, is provided. An original illustration showing the main morphological characters of the new species is...

Journal of Research in Forestry, Wildlife and Environment - Vol 8 ...

African Journals Online (AJOL)

Socio-economic contribution of African breadfruit (Treculia africana Decne) toward sustainable livelihood in eastern, Nigeria · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. O.B. Uluocha, A.U. Udeagha, S.I. Udofia, C.I. Duruigbo, 40-57 ...

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African Journals Online (AJOL)

Evaluation de l'activite antihyperglycemiante de Holarrhena africana, Strophantus hispidus Et Bridelia ferruginea, plantes utilisees dans le traitement du diabete en medecine traditionnelle au Togo Abstract · Vol 17, No 1 (2015) - Articles Distribution et utilites des mauvaises herbes des champs de cultures du campus ...

Determining the correct identity of South African Marthasterias ...

African Journals Online (AJOL)

Although the allopatric distribution, high genetic divergence (more than 3% for the COI fragment) and morphological differences suggest that the South African form should be raised to species status under the name Marthasterias africana, further work must assess an independent genetic marker (nuclear) to support raising ...

Pulmonary nocardiosis caused by Nocardia otitidiscaviarum in an ...

African Journals Online (AJOL)

Nocardia asteroides DSM 43757 AF430019. Nocardia brasiliensis DSM 43758 AF430038. Nocardia farcinica ATCC 3318. Nocardia vinacea MK703-102F1 AB024312. Nocardia jiangxiensis 43401 AY639902. Nocardia miyunensis 117 AY639901. Nocardia vermiculata IFM 0391 AB126873. Nocardia africana DSM 44491 ...

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African Journals Online (AJOL)

Items 251 - 300 of 316 ... Vol 11 (2007), Pyrrolizidine Alkaloids From Cynoglossum furcatam, Abstract. S Ravi, T Ravikumar, A J Lakshmanan. Vol 7 (2003), QUAFRINOIC ACIDS: TWO NEW TRITERPENIODS FROM QUASSIA AFRICANA STEM BARK, Abstract. EO Ajaiyeoba, HC Krebs. Vol 13 (2009), Quality control of ...

Network Simulation

CERN Document Server

Fujimoto, Richard

2006-01-01

"Network Simulation" presents a detailed introduction to the design, implementation, and use of network simulation tools. Discussion topics include the requirements and issues faced for simulator design and use in wired networks, wireless networks, distributed simulation environments, and fluid model abstractions. Several existing simulations are given as examples, with details regarding design decisions and why those decisions were made. Issues regarding performance and scalability are discussed in detail, describing how one can utilize distributed simulation methods to increase the

A HISTÓRIA DA ÁFRICA E DA CULTURA AFROBRASILEIRA NAS ESCOLAS MUNICIPAIS DA CIDADE DE PALMAS – TOCANTINS: REPERCUSSÕES E TENSÕES DA LEI E DAS DIRETRIZES

Directory of Open Access Journals (Sweden)

Ana Lúcia Pereira

2016-09-01

Full Text Available A Lei nº 10.639/03 tornou obrigatória a inclusão de história da África e da cultura afro-brasileira nos currículos escolares. As Diretrizes Curriculares Nacionais para a Educação das Relações Étnico-Raciais e para o ensino de história e cultura afro-brasileira e africana, dela derivada, motivou um movimento pela busca de formação dos professores e pela reformulação e/ou adaptação dos projetos políticos pedagógicos das escolas. O objetivo do texto é o de refletir sobre esse impacto ou as possíveis mudanças no projeto político-pedagógico, bem como os materiais disponibilizados nas bibliotecas e as questões ligadas às religiões de matriz africana nas escolas municipais de ensino fundamental, da cidade de Palmas/TO.

Design of simulation-based medical education and advantages and disadvantages of in situ simulation versus off-site simulation.

Science.gov (United States)

Sørensen, Jette Led; Østergaard, Doris; LeBlanc, Vicki; Ottesen, Bent; Konge, Lars; Dieckmann, Peter; Van der Vleuten, Cees

2017-01-21

Simulation-based medical education (SBME) has traditionally been conducted as off-site simulation in simulation centres. Some hospital departments also provide off-site simulation using in-house training room(s) set up for simulation away from the clinical setting, and these activities are called in-house training. In-house training facilities can be part of hospital departments and resemble to some extent simulation centres but often have less technical equipment. In situ simulation, introduced over the past decade, mainly comprises of team-based activities and occurs in patient care units with healthcare professionals in their own working environment. Thus, this intentional blend of simulation and real working environments means that in situ simulation brings simulation to the real working environment and provides training where people work. In situ simulation can be either announced or unannounced, the latter also known as a drill. This article presents and discusses the design of SBME and the advantage and disadvantage of the different simulation settings, such as training in simulation-centres, in-house simulations in hospital departments, announced or unannounced in situ simulations. Non-randomised studies argue that in situ simulation is more effective for educational purposes than other types of simulation settings. Conversely, the few comparison studies that exist, either randomised or retrospective, show that choice of setting does not seem to influence individual or team learning. However, hospital department-based simulations, such as in-house simulation and in situ simulation, lead to a gain in organisational learning. To our knowledge no studies have compared announced and unannounced in situ simulation. The literature suggests some improved organisational learning from unannounced in situ simulation; however, unannounced in situ simulation was also found to be challenging to plan and conduct, and more stressful among participants. The importance of

Simulation reframed.

Science.gov (United States)

Kneebone, Roger L

2016-01-01

Simulation is firmly established as a mainstay of clinical education, and extensive research has demonstrated its value. Current practice uses inanimate simulators (with a range of complexity, sophistication and cost) to address the patient 'as body' and trained actors or lay people (Simulated Patients) to address the patient 'as person'. These approaches are often separate.Healthcare simulation to date has been largely for the training and assessment of clinical 'insiders', simulating current practices. A close coupling with the clinical world restricts access to the facilities and practices of simulation, often excluding patients, families and publics. Yet such perspectives are an essential component of clinical practice. This paper argues that simulation offers opportunities to move outside a clinical 'insider' frame and create connections with other individuals and groups. Simulation becomes a bridge between experts whose worlds do not usually intersect, inviting an exchange of insights around embodied practices-the 'doing' of medicine-without jeopardising the safety of actual patients.Healthcare practice and education take place within a clinical frame that often conceals parallels with other domains of expert practice. Valuable insights emerge by viewing clinical practice not only as the application of medical science but also as performance and craftsmanship.Such connections require a redefinition of simulation. Its essence is not expensive elaborate facilities. Developments such as hybrid, distributed and sequential simulation offer examples of how simulation can combine 'patient as body' with 'patient as person' at relatively low cost, democratising simulation and exerting traction beyond the clinical sphere.The essence of simulation is a purposeful design, based on an active process of selection from an originary world, abstraction of what is criterial and re - presentation in another setting for a particular purpose or audience. This may be done within

Design of simulation-based medical education and advantages and disadvantages of in situ simulation versus off-site simulation

DEFF Research Database (Denmark)

Sørensen, Jette Led; Østergaard, Doris; LeBlanc, Vicki

2017-01-01

that choice of setting for simulations does not seem to influence individual and team learning. Department-based local simulation, such as simulation in-house and especially in situ simulation, leads to gains in organisational learning. The overall objectives of simulation-based education and factors......BACKGROUND: Simulation-based medical education (SBME) has traditionally been conducted as off-site simulation in simulation centres. Some hospital departments also provide off-site simulation using in-house training room(s) set up for simulation away from the clinical setting, and these activities...... simulations. DISCUSSION: Non-randomised studies argue that in situ simulation is more effective for educational purposes than other types of simulation settings. Conversely, the few comparison studies that exist, either randomised or retrospective, show that choice of setting does not seem to influence...

Safety by simulation; Sicherheit durch Simulation

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, Eberhard [KSG Kraftwerks-Simulator-Gesellschaft mbH, Essen (Germany); GfS Gesellschaft fuer Simulatorschulung mbH, Essen (Germany)

2009-06-15

Simulator training is a key component in achieving and preserving on the long term the necessary expertise of plant personnel also required by the authorities. In this way, it makes an important contribution to the safe operation of nuclear power plants. Simulators are a component in the training of operating personnel of nuclear power plants which allows nuclear power plant operators to be prepared in a focused and practice-oriented way for their activity in everyday plant operation and for possible accident simulation. The simulator center is supported by 5 nuclear power plant operators: the German E.ON Kernkraft GmbH, RWE Power AG, EnBW Kraftwerke AG, and Vattenfall Europe Nuclear Energy GmbH companies as well as the Netherlands N.V. Electriciteits-Produktiemaatschappij Zuid-Nederland. They established a joint enterprise in Essen which performs in one central place the duty of simulator training incumbent upon all nuclear power plants. (orig.)

Educação permanente em saúde e as Diretrizes Curriculares Nacionais para Educação das relações étnico-raciais e para ensino de História e Cultura Afro-Brasileira e Africana

Directory of Open Access Journals (Sweden)

Rosana Batista Monteiro

Full Text Available Resumo Este texto é um ensaio sobre algumas contribuições que o curso de especialização em Saúde da Mulher Negra pode ter produzido para a abordagem dos conteúdos relacionados nas Diretrizes Curriculares Nacionais para a Educação das Relações Étnico-raciais e para o Ensino de História e Cultura Afro-brasileira e Africana, bem como em atenção à Política Nacional de Saúde Integral da População Negra, com destaque para a educação permanente. A partir de breve contextualização sobre o debate no campo das relações raciais e ações afirmativas no Brasil passamos a apresentar a organização e funcionamento do curso, destacando seus objetivos, conteúdos, estratégias. Com foco nos profissionais da saúde, o curso contou com significativa presença de profissionais da educação básica pública, municipal e estadual, das cidades de São Luís e Pinheiro, no Maranhão, implicando a discussão do tema saúde da população negra (especialmente da mulher negra no âmbito da escola. O curso propiciou a elaboração de projetos de pesquisa relacionados diretamente com o atendimento à saúde de mulheres negras e sua relação com processos formativos de profissionais da área da saúde, bem como educação escolar e saúde de mulheres negras. Pode-se concluir, ainda que provisoriamente, que o curso, na perspectiva da educação permanente, resultou em estratégia eficaz para o desenvolvimento de conteúdos relacionados às DCNERER e, especialmente, de viabilização de implementação da Política Nacional de Saúde Integral da População Negra, realizadas ou desencadeadas nos serviços de saúde pelos cursistas.

Biomass cycles, accumulation rates and nutritional characteristics of ...

African Journals Online (AJOL)

Annual biomass cycles, accumulation rates and nutritional characteristics of forage and non-forage species groups were determined in the canopied and open, uncanopied subhabitats of the herbaceous layer in Burkea africana savanna. The total amount of biomass of all species over the season was significantly greater in ...

Comparative effects of Potash Sodium Chloride (PSC) mixture and ...

African Journals Online (AJOL)

Honey (Mellifica sp) is produced by Apis mellifera africana, widely consumed without prescription or restriction, and has been shown to possess wound healing and antitusive properties. Comparative study of the effects of honey paste and Potash Sodium Chloride (PSC) mixture on the healing of incisional wound on albino ...

Effect of pH and ionic strength on the bioadhesive properties of ...

African Journals Online (AJOL)

Prosopis gum (PG) extracted from Prosopis africana was investigated for bioadhesive properties as affected by pH and ionic strength. The bioadhesive properties were evaluated using the adhesion of gum dispersion-coated glass beads on the antrum region of the porcine gastrointestinal tract and Lecomte Du Nouy ...

In vitro antimicrobial and phytochemical properties of crude extract ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... University of Fort Hare, Alice 5700, South Africa. 2Department of Microbiology, Obafemi Awolowo .... Thus improvement on such extract by pharmaceutical industry to produce antimicrobial drug of ... Table 1. Antimicrobial activity profile of the crude extract of stem bark of A. africana. Zones of inhibition (mm)*.

An endangered species in Cameroon

African Journals Online (AJOL)

Justine Nzweundji

2015-08-19

Aug 19, 2015 ... 2002) and one of the main sources of supply to satisfy this demand consists of Cameroon natural populations. (Nsawir and Ingram, 2007). Unfortunately, much of this exploitation has been ..... Prunus africana: Money growing on trees? A plant that can boost rural economies in the Cameroon Highlands.

SOME MOISTURE DEPENDENT THERMAL PROPERTIES AND ...

African Journals Online (AJOL)

The thermal heat conductivity, specific heat capacity, thermal heat diffusivity and bulk density of Prosopis africana seeds were determined as a function of moisture content. Specific heat capacity was measured by the method of mixture while the thermal heat conductivity was measured by the guarded hot plate method.

Apport de l'approche systémique des systèmes d'élevage à l ...

African Journals Online (AJOL)

Le paysage est occupé par de nouvelles steppes issues de dégradation où dominent Salsola vermiculata, Atractylis serratuloides, Noaea mucronata, Peganum harmala. Les formations psammophytes à Retama raetam, Thymelaea microphylla et Tamarix africana, s'étendent sur plus de 17 %. L'ensablement menace ces ...

Weight analyses and nitrogen balance assay in rats fed extruded ...

African Journals Online (AJOL)

Weight analyses and nitrogen balance assay in adult rats in raw and extruded African breadfruit (Treculia africana) based diets were carried out using response surface methodology in a central composite design. Process variables were feed composition (40 - 100 % African breadfruit, 0 - 5 % corn and 0 - 55 % soybean, ...

Highly polymorphic DNA markers in an Africanized honey bee population in Costa Rica

Directory of Open Access Journals (Sweden)

Jorge Arturo Lobo Segura

2000-06-01

Full Text Available Two genetic markers (the mtDNA COI-COII intergenic region and the microsatellite A7 with high levels of variability in South African and European honey bees were analyzed in wild swarms of Africanized honey bees (Apis mellifera from Costa Rica. Allelic or haplotypic frequencies revealed high levels of genetic variability at these loci in this population. Most of the alleles were African alleles, although some European-derived alleles were also present. Differences in the frequencies of African alleles between African and Africanized samples were minor, which could be explained by founder effects occurring during the introduction of African honey bee populations into South America.Dois marcadores genéticos (a região intergénica mitocondrial COI-COII e o microsatélite A7, com altos níveis de variabilidade em populações de abelhas melíferas da África do Sul e Europa, foram analisados em uma amostra de enxames naturais da Costa Rica. As freqüências alélicas e haplotípicas na amostra africanizada mostraram altos níveis de diversidade nestes loci. A maioria dos alelos são de origem africana, embora alguns alelos de origem européia foram observados. As mudanças nas freqüências dos alelos de origem africana entre as abelhas da África do Sul e as abelhas da população africanizada são de baixa magnitude e podem ter sido causadas pelo efeito fundador que ocorreu na introdução da abelha africana na América do Sul.

The historical significance of African liberation – the views of South African History Education students

Directory of Open Access Journals (Sweden)

Johan Wassermann

2017-01-01

Full Text Available Este estudio se basó en las opiniones de estudiantes sudafricanos de historia de la educación del primer año quienes estudian para convertirse en profesores. En una encuesta abierta, se les pidió que usando su imaginación intelectual, expresen sus opiniones sobre los temas que les gustaría ver como parte del currículo de historia en la escuela. El propósito de esto fue determinar lo que los estudiantes consideraban como históricamente significativo para ser estudiado en historia en la escuela. Las respuestas fueron analizadas mediante codificación abierta y leídas a través de la conceptualización de Counsell de significación histórica. Lo que surgió fue que la lucha contra el apartheid fue considerada sólo por unos pocos como una lucha actual por la liberación contra la colonización interna. Las luchas de liberación africana contra el colonialismo europeo resultaron aún peores y ello sólo fue imaginado por un pequeño número de estudiantes como digno de ser incluido en un currículo de historia escolar. Al mismo tiempo, en ningún momento se relacionó la lucha contra el apartheid a la lucha más amplia de la liberación africana. Esto habla no sólo de la unicidad sudafricana, sino también acerca de la opinión que la lucha de liberación africana no es históricamente significativa como para ser incluida en un currículo de historia imaginado.

Characterization of actinobacteria associated with three ant-plant mutualisms.

Science.gov (United States)

Hanshew, Alissa S; McDonald, Bradon R; Díaz Díaz, Carol; Djiéto-Lordon, Champlain; Blatrix, Rumsaïs; Currie, Cameron R

2015-01-01

Ant-plant mutualisms are conspicuous and ecologically important components of tropical ecosystems that remain largely unexplored in terms of insect-associated microbial communities. Recent work has revealed that ants in some ant-plant systems cultivate fungi (Chaetothyriales) within their domatia, which are fed to larvae. Using Pseudomyrmex penetrator/Tachigali sp. from French Guiana and Petalomyrmex phylax/Leonardoxa africana and Crematogaster margaritae/Keetia hispida, both from Cameroon, as models, we tested the hypothesis that ant-plant-fungus mutualisms co-occur with culturable Actinobacteria. Using selective media, we isolated 861 putative Actinobacteria from the three systems. All C. margaritae/K. hispida samples had culturable Actinobacteria with a mean of 10.0 colony forming units (CFUs) per sample, while 26 % of P. penetrator/Tachigali samples (mean CFUs 1.3) and 67 % of P. phylax/L. africana samples (mean CFUs 3.6) yielded Actinobacteria. The largest number of CFUs was obtained from P. penetrator workers, P. phylax alates, and C. margaritae pupae. 16S rRNA gene sequencing and phylogenetic analysis revealed the presence of four main clades of Streptomyces and one clade of Nocardioides within these three ant-plant mutualisms. Streptomyces with antifungal properties were isolated from all three systems, suggesting that they could serve as protective symbionts, as found in other insects. In addition, a number of isolates from a clade of Streptomyces associated with P. phylax/L. africana and C. margaritae/K. hispida were capable of degrading cellulose, suggesting that Streptomyces in these systems may serve a nutritional role. Repeated isolation of particular clades of Actinobacteria from two geographically distant locations supports these isolates as residents in ant-plant-fungi niches.

Simulating Shopper Behavior using Fuzzy Logic in Shopping Center Simulation

Directory of Open Access Journals (Sweden)

Jason Christian

2016-12-01

Full Text Available To simulate real-world phenomena, a computer tool can be used to run a simulation and provide a detailed report. By using a computer-aided simulation tool, we can retrieve information relevant to the simulated subject in a relatively short time. This study is an extended and complete version of an initial research done by Christian and Hansun and presents a prototype of a multi-agent shopping center simulation tool along with a fuzzy logic algorithm implemented in the system. Shopping centers and all their components are represented in a simulated 3D environment. The simulation tool was created using the Unity3D engine to build the 3D environment and to run the simulation. To model and simulate the behavior of agents inside the simulation, a fuzzy logic algorithm that uses the agents’ basic knowledge as input was built to determine the agents’ behavior inside the system and to simulate human behaviors as realistically as possible.

Biogeography and molar morphology of Pleistocene African elephants: new evidence from Elandsfontein, Western Cape Province, South Africa

Science.gov (United States)

Smith, Kathlyn M.; Stynder, Deano D.

2015-05-01

Elandsfontein (EFT) is a Middle Pleistocene archaeological/paleontological site located in the Western Cape Province of South Africa. The largest herbivore in the assemblage is Loxodonta atlantica zulu, an extinct member of the genus that includes modern African elephants. No Elephas recki specimens were recovered at EFT, despite their common occurrence in other regions of Africa at the same time. Because E. recki and L. atlantica molars are similar in appearance, but the two species are traditionally viewed as dominating different regions of Africa during the Pleistocene, isolated molars may on occasions have been assessed to species level on the basis of geography rather than morphology. The last morphologic evaluation of EFT elephants was conducted in the 1970s, and revisiting this issue with new specimens provides added insight into the evolution of elephants in Africa. Reevaluating morphological characteristics of EFT elephant molars, through qualitative and quantitative description and comparison with Middle Pleistocene E. recki recki, L. atlantica atlantica, and L. atlantica zulu molar morphology, corroborates assessment of EFT elephants as L. a. zulu. Two recently discovered, previously undescribed molars from EFT show that molars of L. a. zulu exhibit greater variation in enamel thickness, lamellar frequency, and occlusal surface morphology than previously reported. An update of the Pleistocene biogeography of Loxodonta and Elephas indicates that fossil remains of both are often found at the same localities in eastern Africa. Their rare co-occurrences in the north and south, however, suggest geographic separation of the two genera in at least some regions of Africa, which may have been based on habitat preference.

???????????? SolidWorks/SolidWorks Flow Simulation/SolidWorks Simulation ??? ?????????? ???????? ?? ????????????? ???

OpenAIRE

????????????, ?. ?.; ????????, ?. ?.; ?????, ?. ?.

2012-01-01

? ?????? ???????? ??????? ??????? ???????? ?? ???????????? ??????????? ????????? SolidWorks/SolidWorks Flow Simulation (COSMOSFloWorks)/SolidWorks Simulation ??? ?????????? ???????? ?? ????????????? ???. ??? ???????? ????????? ???????? ?????????? ?? ?????? ???????? ??????? ? ????????????? ?????? ? ????????????? ????????????? ?????????? ???????????? SolidWorks Flow Simulation (COSMOSFloWorks). ??? ???????????? ??????????? ????????????? ?????? ?? ????????? ??????????? ??????? ?? ??????????? ...

Simulation Interoperability (Interoperabilite de la simulation)

Science.gov (United States)

2015-01-01

dans les environnements de simulation (distribuée) ». Ce guide augmente le DSEEP relativement à l’élaboration des scénarios et propose un contenu et...Recommandations de mise à jour de l’AMSP-01 [AMSP-01] relativement à l’interopérabilité de la simulation et au développement des scénarios...detectable that are not included. • The effect of losses on morale in a constructive simulation system which would impair effectiveness is difficult to

Reflexión sobre la dimensión espectatorial de las películas africanas: o cómo los cines africanos piensan de otra manera en sus públicos / Reflection On the Spectatorial Dimension of African Films: Or How African Cinemas Think About Their Public Different

Directory of Open Access Journals (Sweden)

Mahomed Bamba

2016-03-01

Full Text Available Este artículo investiga la construcción textual del espectador en varias películas africanas. Un espectador que aparece inscrito «en filigrana» a través de los ges-tos enunciativos y estrategias paratextuales de cineastas que siguen la lógica poética del cine de autor. Es a través del análisis de estas estrategias estilísticas y narrativas, de los recursos simbólicos utilizados, de las huellas metadiscursivas presentes en los textos, como se puede averiguar, más allá de las intenciones expresadas por los propios cineastas, o de los resultados en taquilla, en qué medida los autores han pensado o no en los públicos africanos, y si se dirigen exclusivamente a ellos.Palabras clave: relato, sistema textual, paratexto, espectador implícito, semiopragmática, griot, cine de autor.AbstractThis article explores the textual construction of the spectator in various African films. A spectator that seems to be registered as a ‘watermark’ through the expository gestures and paratextual strategies of filmmakers that follow the poetic logic of auteur cinema. It is through the analysis of these stylistic and narrative strategies, of the symbolic resources used, and of the metadiscursive traces present in the texts, that the extent to which the authors have taken into consideration the African audience, and whether or not they are aiming exclusively at them, can be explored - even in terms beyond those directly expressed by the filmmakers themselves.Keywords: story, textual system, paratext, implicit spectator, semio-pragmatics, griot, auteur cinema

Traços do proprium cultural africano e sua relação com o sagrado (Features of African culture and conceptions of the sacred - DOI: 10.5752/P.2175-5841.2013v11n29p88

Directory of Open Access Journals (Sweden)

Antonio Geraldo Cantarela

2013-03-01

Full Text Available Na esteira da conquista colonial de África, desencadeada na segunda metade do século XIX, alguns antropólogos e missionários europeus, que estabeleceram longa convivência com sociedades de diferentes regiões do continente  africano, lograram realizar as primeiras recolhas e sistematizações acadêmicas do imaginário cultural de comunidades tradicionais. Tomando tal contexto como pano de fundo e contraponto, o artigo destaca algumas vozes de teóricos “nativos” (Ki-Zerbo, Hampaté Bâ, Honorat Aguessy, com vistas a explicitar e discutir alguns traços do proprium cultural africano. Na concepção daquelas culturas tradicionais, a religião, assentada no mesmo arco da cultura oral, funda todos os demais componentes da vida social. Sobre tal pressuposto, o texto discute quatro aspectos principais: a concepção (ingênua de uma unidade cultural africana; a importância da tradição oral para o conhecimento da história e do imaginário das sociedades daquele continente; as imbricações da ação política e das questões culturais;  as polarizações (desnecessárias de Europa versus África para fins de caracterizar adequadamente as culturas africanas. Palavras-chave: Culturas africanas. Religião tradicional africana. Oralidade.   Abstract During the colonial conquest of Africa, which began in the second half of the nineteenth century, some European missionaries and anthropologists, who have established long acquaintance with some societies from different regions of Africa, managed to make the first academic collection and systematization of African traditional thought. Taking such a context as a backdrop and counterpoint, this article highlights some voices of African theorists (Ki-Zerbo, Hampaté Bâ, Honorat Aguessy, in order to explain and discuss some essential features of African culture. Within the traditional African conception, the religion, founded on the same pillars of oral culture, founds all other components of

Some behavioural studies on methanol root bark extract of Burkea ...

African Journals Online (AJOL)

The research was conducted to evaluate some central nervous system properties of the root bark methanol extractof B. africana in mice. It involved the following animal models: diazepam-induced sleep, hole-board and walking beam assay. Results: The methanol extract showed a significant decrease in the onset of sleep ...

The relative importance of climatic gradient versus human ...

African Journals Online (AJOL)

The study aimed to investigate the relative significance of effects of climatic variability and human disturbance on the population structure of the threatened species Afzelia africana Sm. ex Pers. in the Republic of Benin in West Africa. Forest inventory data such as regeneration density, tree diameter and total height were ...

Pollination and facultative ant-association in the African leopard ...

African Journals Online (AJOL)

The role of extra-floral nectar appears to be recruitment of foraging ants to tend the flowers resulting in a facultative ant-association between the orchid and gregarious ants. Four different ant species were found to forage on A. africana's inflorescences. Ant-tended inflorescences suffered significantly less damage by insects.

Chemical composition and in vitro dry matter digestibility of Moringa ...

African Journals Online (AJOL)

The effect of caecal inoculum of rabbit on in vitro gas production and dry matter digestibility of Moringa oleifera, Azadirachta indica and Aspilia africana leaf meals at different levels of 0%, 15% and 30%. Leave samples were analyzed for crude protein (CP), lignin (ADL), acid (ADF) and neutral (NDF) detergent fibres.

Effect of temperature, light intensity and growth regulators on ...

African Journals Online (AJOL)

Ansellia africana (Orchidaceae) is an important endangered medicinal plant species of South Africa which has been heavily exploited in recent years. Experiments were conducted in growth rooms at different temperatures (16, 26, 36°C) and in a nursery at different light intensities induced by shade cloth densities (200, 400, ...

Ajeigbe et al., Afr J Tradit Complement Altern Med. (2013) 10(5):236 ...

African Journals Online (AJOL)

AJTCAM

major source of drug development in the pharmaceutical industry (Burton et al., 1983). Several plants are ... Okoli et al., 2007). In South-eastern Nigeria, leaves of this plant is claimed to be ..... Table 4.1: Haematological Profile of Rats Administered with Different Concentrations of Aqueous Extract of Aspilia africana. GROUP.

Effect of temperature, light intensity and growth regulators on ...

African Journals Online (AJOL)

ONOS

2010-08-23

Aug 23, 2010 ... A. africana plants were cut into two lengths, the top leafy shoot and the bottom part ... of cuttings were used: a) mature cuttings with both green leaves and an inflorescence, b) mature .... An increase in NAA concentration applied to cuttings ..... subsequent development of New Guinea impatiens and petunia.

(Ortmann) (Decapoda, Crustacea)

African Journals Online (AJOL)

1987-03-13

Mar 13, 1987 ... duration and current velocity) of the populations to the flow of water ... The mud prawn Upogebia africana (Ortmann) is a filter ... three sources namely, treated sewage released into the ... indicating the positions of the sampling sites for macrobenthos (1 - 40) ..... punctata feeding on a variety of marine algae.

Blood glucose response of normoglycemic adults fed breakfast ...

African Journals Online (AJOL)

Gift

Effect of high fibre leguminous products in breakfast porridges, made from Afzelia Africana (AA), ... Fasting and postprandial blood glucose levels were taken at 30 min interval for 2 .... ml to CSS and each was cooked (stirred continuously) for 10 min to ..... prevalence of diabetes, overweight/obesity and physical inactivity in.

Browse Title Index

African Journals Online (AJOL)

L Somigli. Vol 22, No 2 (2009), Antropologia di un intellettuale, Giuseppe Cassieri, Abstract PDF. G Sotis. Vol 14, No 2 (2001), Apprendere una lingua straniera: tempo e spazio nella cultura italiana, Abstract PDF. C Samson. Vol 26, No 1 (2013), Appunti pasoliniani per un'orestiade africana, Abstract PDF. M Chiacchiararelli.

Browse Title Index

African Journals Online (AJOL)

Vol 3, No 2 (2007), Exploitation des fleurs de Entada africana, Eucalyptus ... Growth and α-amylase production by strains of Lactobacillus plantarum and ... alata seedlings to host soil mycorrhizal inocula in relation to land use types, Abstract .... Vol 6, No 2 (2010), Properties of Arginase from the Hepatopancreas of Giant ...

Author Details

African Journals Online (AJOL)

Evaluation de l'activite antihyperglycemiante de Holarrhena africana, Strophantus hispidus Et Bridelia ferruginea, plantes utilisees dans le traitement du diabete en medecine traditionnelle au Togo Abstract · Vol 16, No 3 (2014) - Articles Effet anti-ulcereux de l'extrait hydroalcoolique D'ecorce de tronc et de racine de Ficus ...

Can serums be replaced by Mueller‑Hinton agar in germ tube test ...

African Journals Online (AJOL)

Background: The germ tube test (GTT) is inexpensive, easy, and well‑defined test that differentiates Candida albicans (excluding Candida dubliniensis and Candida africana) from other species. The aim of this study was to evaluate various serums (i.e., human, rabbit, horse, and fetal bovine serum) used in the GTT and ...

Phytochemical evaluation and antibacterial profile of Treculia ...

African Journals Online (AJOL)

presence of steroidal saponin glycosides as the major component, anthraquinone glycoside and polyphenols. Our results offer a scientific basis for the traditional use of T. africana. The aqueous ethanol extract of the bark was effective in vitro in this study on gastrointestinal bacteria pathogens, and thus could be explored for ...

Fanon and Development: A Philosophical Look | Gordon | Africa ...

African Journals Online (AJOL)

The rest of the article presents an Africana postcolonial phenomenological treatment of freedom as a dialectical relationship between the lived reality of choices and social options and the need for a radical humanistic globalism with which to fight contemporary neoliberal and conservative ones. Résumé Cet article analyse ...

Simulating Vito

CERN Document Server

Fragapane, Alexander

2013-01-01

This paper discusses the techniques used to simulate the proposed upgrade to the ASPIC line at ISOLDE, VITO. It discusses the process used in the program SIMION by explaining how to start with an Autodesk Inventor drawing and import this into SIMION to get a working simulation. It then goes on to discuss the pieces of VITO which have been simulated in the program and how they were simulated. Finally, it explains a little about the simulations of the full beamline which have been done and discusses what still needs to be done.

Design of simulation-based medical education and advantages and disadvantages of in situ simulation versus off-site simulation

NARCIS (Netherlands)

Sorensen, J.L.; Ostergaard, D.; Leblanc, V.; Ottesen, B.; Konge, L.; Dieckmann, P.; Vleuten, C. van der

2017-01-01

BACKGROUND: Simulation-based medical education (SBME) has traditionally been conducted as off-site simulation in simulation centres. Some hospital departments also provide off-site simulation using in-house training room(s) set up for simulation away from the clinical setting, and these activities

Scientia Africana - Vol 13, No 1 (2014)

African Journals Online (AJOL)

Analytical modeling of pipeline failure in multiphase flow due to corrosion in Niger ... oxide photovoltaic cell for teaching purpose using locally available materials ... Analysis of filtration properties of locally sourced base oil for the formulation of ...

Scientia Africana - Vol 10, No 1 (2011)

African Journals Online (AJOL)

Open Access DOWNLOAD FULL TEXT ... Preparation and characterization of activated carbon from water hyacinth ... Gender inequality and diseases in Nigeria: a case study of HIV/AIDS and malaria · EMAIL FULL TEXT EMAIL FULL TEXT

Scientia Africana - Vol 11, No 2 (2012)

African Journals Online (AJOL)

SQLdefend: An automated detection and prevention technique for sql injection vulnerabilities in web applications · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. E.E. Ogheneovo, P.O. Asagba ...

Scientia Africana - Vol 14, No 1 (2015)

African Journals Online (AJOL)

Synthesis, characterization and antibacterial activity of Fe(II) mixed ligands complex of succinic acid and hexamethylenetetramine · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. J. I. Mbonu, M. Ariemudwigho ...

Hypoglycaemic activity of commelina africana and ageratum

African Journals Online (AJOL)

Administrator

Background: Many plants with antidiabetic properties probably act in part through their content of fibre, vitamins, bioactive or mineral ... in Asia and Africa probably due to the adoption of a Western ... Some of the leaves were air dried, ground to ...

UTILIZATION OF Prosopis africana PULP FOR RABBIT

African Journals Online (AJOL)

IBB

protein and less fat and calories per gram than beef, ... unlimited green vegetables, roots and hay, but the ... representing 1450 kg of meat which is equal to an .... iron, 50g; manganese 50g; zinc, 50g; Iodine, 0.78g; Cobalt 0.25g; Copper 5.0g; ...

Scientia Africana - Vol 11, No 1 (2012)

African Journals Online (AJOL)

Prognostic diagnosis of pelvic inflammatory disease utilizing logical fuzzy ... Some observations on derivatives of orthogonal polynomials · EMAIL FULL TEXT ... output performance of solar power system · EMAIL FULL TEXT EMAIL FULL TEXT

Scientia Africana - Vol 12, No 2 (2013)

African Journals Online (AJOL)

Stabilizing the border steady-state solution of two interacting populations · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. N.M. Nafo, E.N. Ekaka-a. Stability analysis of predator-prey interaction with a crowding effect · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL ...

DeepSimulator: a deep simulator for Nanopore sequencing

KAUST Repository

Li, Yu

2017-12-23

Motivation: Oxford Nanopore sequencing is a rapidly developed sequencing technology in recent years. To keep pace with the explosion of the downstream data analytical tools, a versatile Nanopore sequencing simulator is needed to complement the experimental data as well as to benchmark those newly developed tools. However, all the currently available simulators are based on simple statistics of the produced reads, which have difficulty in capturing the complex nature of the Nanopore sequencing procedure, the main task of which is the generation of raw electrical current signals. Results: Here we propose a deep learning based simulator, DeepSimulator, to mimic the entire pipeline of Nanopore sequencing. Starting from a given reference genome or assembled contigs, we simulate the electrical current signals by a context-dependent deep learning model, followed by a base-calling procedure to yield simulated reads. This workflow mimics the sequencing procedure more naturally. The thorough experiments performed across four species show that the signals generated by our context-dependent model are more similar to the experimentally obtained signals than the ones generated by the official context-independent pore model. In terms of the simulated reads, we provide a parameter interface to users so that they can obtain the reads with different accuracies ranging from 83% to 97%. The reads generated by the default parameter have almost the same properties as the real data. Two case studies demonstrate the application of DeepSimulator to benefit the development of tools in de novo assembly and in low coverage SNP detection. Availability: The software can be accessed freely at: https://github.com/lykaust15/DeepSimulator.

Power station simulators

International Nuclear Information System (INIS)

Zanobetti

1989-01-01

The number and the variety of simulators have gown to such an extent that it has become necessary to classify the numerous types now available. Simulators are of paramount importance for the design of nuclear power plants, for optimizing their efficiency and for the training of their operators: factors that contribute to their overall security. This book contains chapters on the following subjects: the development of power plant simulators, the components and classification of simulators, simulator technology, simulator performance and problems in simulator training

A trouser bag experiment that quantify by-catch species escaping ...

African Journals Online (AJOL)

Sea fishing trials were conducted to quantify by-catch species escaping from a modified shrimp trawl codend and retained in a trouser bag. Modification was by inserting a rectangular aluminum frame excluder device with bar spacing of 20mm at the anterior bunt. Thirty replicate landings showed that; Drepane africana have ...

Morphometric studies on Culex quinquefasciatus and Mansonia ...

African Journals Online (AJOL)

are difficult to identify based solely on examination of adult females using the available morphological keys. In this study, adult mosquitoes were collected ... ures) it is necessary to identify the species of adult females which are found near ... M. africana is known to transmit Rift Valley fever. (Meegan & Bailey, 1988; Fontenille ...

PROJECT WORK BY STUDENTS FOR FIRST DEGREE: AN ...

African Journals Online (AJOL)

Mofasony

It is expected that after University education, student of law should write well as ... student's capability, topics should not be assigned to students collectively. .... This enables the student hone-in the theoretical course work in the university. There is no .... Benson O.A. Oluikpe, Thesis Writing, Africana Publishers Ltd, 1982, iv. 7.

AFRICA LOSES AN EXCELLENT BOTANIST AND TEACHER ...

African Journals Online (AJOL)

L.A

2017-04-20

Apr 20, 2017 ... publications were illustrated with pictures of bats landing on moving pendulous inflorescences in the dark. He was always ready for a field ... University of Dar es Salaam. Unpublished mimeo. 19 Pages. Harris, B.J. & H.G. Baker (1958). Pollination in Kigelia africana Benth. Journal of West. African Science ...

(MTT) dye reduction assay.

African Journals Online (AJOL)

to inhibit proliferation of HeLa cells was determined using the 3443- dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) dye reduction assay. Extracts from roots of Agathisanthemum bojeri, Synaptolepis kirkii and Zanha africana and the leaf extract of Physalis peruviana at a concentration of 10 pg/ml inhibited cell ...

Vozes afro-americanas: a alteridade em suas várias faces

Directory of Open Access Journals (Sweden)

Maria Nazareth Soares Fonseca

1996-10-01

Full Text Available Este artigo pretende refletir sobre a presença de imagens que anunciam, em textos literários produzidos na América Latina, a recuperação da cultura africana e sua importância na construção de discursos sobre a alteridade do continente.

Untitled

African Journals Online (AJOL)

The rare alkaloid 4-methylthiocanthin-6-one has been isolated from the root bark of Quassia africana (Simaroubaceae) together with 5-methoxycanthin-6- one. The MS, 'H NMR and 3C NMR data for 4-methylthiocanthin-6-one are reported herein for the first time. In particular, unambiguous assignment of the 130 NMR.

Effects of sun and shade drying on nutrient and antinutrient content ...

African Journals Online (AJOL)

This work determined the effect of sun and shade drying on the nutrient, antinutrient and food toxicant composition of atama – Heinsia crinata, editan - Lasianthore Africana and water – leaf – Talinum tringulare vegetables. Two and a half kilogram of these green leafy vegetable were purchased from Uyo market, picked from ...

Three new fern records for Kilimanjaro | Hemp | Journal of East ...

African Journals Online (AJOL)

Working on the flora and vegetation of Mt. Kilimanjaro, Tanzania, three ferns in three families were found that are not yet recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum reniforme, Azolla africana and Trichomanes radicans. Journal of East African Natural History ...

Performance of rabbits fed Leucaena leucocephala and concentrate ...

African Journals Online (AJOL)

Four fryers which were fed the same % of concentrates and Aspilia africana served as the control. Growth rate decreased at the beginning of the study followed by satisfactory growth thereafter. The control animals had a higher growth rate compared to the other two groups (P< 0.05). Alopecia and decreased appetite were ...

An African-Centred Approach to Land Education

Science.gov (United States)

Engel-Di Mauro, Salvatore; Carroll, Karanja Keita

2014-01-01

Approaches to environmental education which are engaging with place and critical pedagogy have not yet broadly engaged with the African world and insights from Africana Studies and Geography. An African-centred approach facilitates people's reconnection to places and ecosystems in ways that do not reduce places to objects of conquest and…

Simulator justifications

International Nuclear Information System (INIS)

Fairchild, B.T.

1990-01-01

For several years, the authors have been convinced by overwhelming evidence that dynamic simulators are justified for many applications where acceptance has been slow. They speculate as to why this situation has existed and list many benefits that accrue to those who use simulators for training and other purposes. This paper along may be sufficient to convince a receptive approval chain of the value of simulator ownership. It is intended primarily as an aid and supporting document for those who find it necessary to build a detailed justification for a specific simulator acquisition. The purchase of a simulator requires justification. For new military aircraft and for spacecraft, a simulator for training and performance evaluation is virtually assumed, value having been proven many times over. for commercial aircraft, safety is the overwhelming justification. For nuclear power plants, government regulations require operators to be licensed by examination on a certified simulator. For other applications, including air traffic control, biomedical, communications, electronic power transmission and distribution, emergency engineering and management, fossil power plants, gaming land vehicles, manufacturing, maintenance, marine vehicles, process plants, weapons, etc

ALLAN.simulation club; Club ALLAN.simulation

Energy Technology Data Exchange (ETDEWEB)

Boudaud, F

1994-05-27

The ALLAN.Simulation code was developed by the R and D direction of Gaz de France (GdF) company with the support of CISI and Dassault Data Services companies. Its aim is to provide a modeling tool for the design and operation of complex technical systems. It uses a `boxes and ropes` representation (non-oriented multi-variable bloc-schemes) which allows the re-use of all or part of previous models or analyses already developed and recorded. The third meeting of the non-GdF users of the ALLAN.Simulation code took place at Sophia Antipolis (France) on May 27, 1994. Several studies performed with ALLAN.Simulation were presented and dealt with: a thermohydraulic loop, an alternator for automobile, and the hydration of cements. This report is a compilation of the transparencies relative to these three studies. A last part is devoted the presentation of the possible links between different existing simulation codes: ALLAN, BASILE, MAPLE, NEPTUNIX. (J.S.)

Software for simulation of nuclear simulation of nuclear installations

International Nuclear Information System (INIS)

Castaneda, J.O.; Ramos, L.M.; Arjona, O.; Rodriguez, L.

1993-01-01

The software is an instrument to build conceptual-type simulators of low, medium and full scale for used in nuclear installations. The system is composed by composed by two basic modules: one for the edition and the other for the simulation. The first one allows to prepare the information to simulate: mathematical model, technological design (fundamentally, operation board or mnemotechnical design), parameters to be shown, failures to be simulated

Ciudades soñadas y ciudades en las que es imposible soñar: la narrativa de Guinea Ecuatorial

Directory of Open Access Journals (Sweden)

Dorothy Odartey-Wellington

2012-11-01

Full Text Available Este trabajo examina las contribuciones de los escritores contemporáneos de Guinea Ecuatorial a la construcción de nociones de ciudades y sus habitantes en la narrativa africana contemporánea. Aunque el documento se basa principalmente en obras de María Nsue Angüe, Maximiliano Nkogo Esono, Juan Tomás Ávila Laurel, Donato Ndongo-Bidyogo y César Mba Abogo, la interpretación de estos escritores de las ciudades se examina en relación con un contexto más amplio de la escritura africana representada por los siguientes autores anglófonos, Ama Ata Aidoo, Sefi Atta, Kojo Laing y Sinyangwe Binwell así como la francófona Calixthe Beyala. El tratamiento particular de ciudades por parte de los escritores guineoecuatorianos, en comparación con las tendencias en otros ejemplos de la literatura y crítica africanas, tiene su origen en las preocupaciones socio-políticas en el contexto de la petroeconomía de su país. This paper examines the contributions of contemporary Equatoguinean writers to the construction of ideas of cities and their inhabitants in contemporary African narrative. Although the paper draws mainly on works by María Nsue Angüe, Maximiliano Nkogo Esono, Juan Tomás Ávila Laurel, Donato Ndongo-Bidyogo and César Mba Abogo, these writers’ rendition of cities is examined with reference to a wider context of African writing represented by Anglophone and Francophone writers Ama Ata Aidoo, Sefi Atta, Kojo Laing, Binwell Sinyangwe and Calixthe Beyala. The particular treatment of Equatoguinean cities in comparison to trends in other examples of African literature and criticism, are traced to the socio-political concerns in the context of Equatorial Guinean new petro-economy.

Distribución de tres polimorfismos del gen TSLP en población afrodescendiente de San Basilio de Palenque, Colombia

Directory of Open Access Journals (Sweden)

Luis Fang

2013-06-01

Full Text Available Introducción. La linfopoyetina tímica del estroma (Thymic Stromal Lymphopoietin, TSLP se ha vinculado como un gen de propensión al desarrollo de enfermedades alérgicas. Se sabe que la población de Cartagena es una mezcla triétnica, en la cual el componente de herencia africana se asoció con el riesgo de asma y altos niveles séricos de IgE total. Este componente provino de esclavos africanos que lograron organizarse en “palenques”, uno de ellos es San Basilio de Palenque, en la Costa Caribe colombiana. Objetivo. Determinar la distribución de los polimorfismos de nucleótido simple (Single Nucleotide Polymorphism, SNP rs1837253, rs17551370 y rs2289276 del gen TSLP en individuos afrodescendientes de San Basilio de Palenque. Materiales y métodos. Mediante PCR en tiempo real y sondas TaqMan SNP Genotyping™ segenotipificaron estos SNP en 80 individuos afrodescendientes entre los 5 y 18 años de edad. Resultados. El alelo de menor frecuencia para el polimorfismo rs1837253 fue el alelo T (41,9 %, para el rs17551370, el alelo A (14,3 %, y para el rs2289276, el alelo T (22,5 %. La distribución de los polimorfismos rs17551370 y rs2289276 se mantuvo en equilibrio genético de Hardy-Weinberg. Las frecuencias alélicas de cada SNP no mostraron diferencias significativas con las reportadas para poblaciones africanas. Conclusiones. Los tres polimorfismos analizados en el gen TSLP estuvieron presentes en la muestra de población de San Basilio de Palenque y su distribución es similar a la reportada para poblaciones africanas y para poblaciones americanas de ancestro africano. doi: http://dx.doi.org/10.7705/biomedica.v33i2.655

Phylogenetic fragrance patterns in Nicotiana sections Alatae and Suaveolentes.

Science.gov (United States)

Raguso, Robert A; Schlumpberger, Boris O; Kaczorowski, Rainee L; Holtsford, Timothy P

2006-09-01

We analyzed floral volatiles from eight tobacco species (Nicotiana; Solanaceae) including newly discovered Brazilian taxa (Nicotiana mutabilis and "Rastroensis") in section Alatae. Eighty-four compounds were found, including mono- and sesquiterpenoids, nitrogenous compounds, benzenoid and aliphatic alcohols, aldehydes and esters. Floral scent from recent accessions of Nicotiana alata, Nicotiana bonariensis and Nicotiana langsdorffii differed from previously published data, suggesting intraspecific variation in scent composition at the level of biosynthetic class. Newly discovered taxa in Alatae, like their relatives, emit large amounts of 1,8-cineole and smaller amounts of monoterpenes on a nocturnal rhythm, constituting a chemical synapomorphy for this lineage. Fragrance data from three species of Nicotiana sect. Suaveolentes, the sister group of Alatae, (two Australian species: N. cavicola, N. ingulba; one African species: N. africana), were compared to previously reported data from their close relative, N. suaveolens. Like N. suaveolens, N. cavicola and N. ingulba emit fragrances dominated by benzenoids and phenylpropanoids, whereas the flowers of N. africana lacked a distinct floral scent and instead emitted only small amounts of an aliphatic methyl ester from foliage. Interestingly, this ester also is emitted from foliage of N. longiflora and N. plumbaginifolia (both in section Alatae s.l.), which share a common ancestor with N. africana. This result, combined with the synapomorphic pattern of 1,8 cineole emission in Alatae s.s., suggests that phylogenetic signal explains a major component of fragrance composition among tobacco species in sections Alatae and Suaveolentes. At the intraspecific level, interpopulational scent variation is widespread in sect. Alatae, and may reflect edaphic specialization, introgression, local pollinator shifts, genetic drift or artificial selection in cultivation. Further studies with genetically and geographically well

Nigerian Journal of Health and Biomedical Sciences - Vol 2, No 2 ...

African Journals Online (AJOL)

Aqueous extract of the Bark of Kigelia africana reverses early testicular damage induced by methanol extract of Carica Papaya · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. AIR Abioye, FIO Duru, CC Noronha, AO Okanlawon, 87-89. http://dx.doi.org/10.4314/njhbs.v2i2.11491 ...

Questione Meridionale And Global South: If The Italian South Meets ...

African Journals Online (AJOL)

Il saggio prova ad affrontare la vexata questio meridionale alla luce di quello che è stato il dibattito italiano negli ultimi anni a partire dai benevoli influssi degli studi postcoloniali e del cosiddetto “pensiero meridiano”. Partendo dall'imagery africana dominante (orientalista e non) con cui spesso il sud d'Italia è stato descritto ...

Bio-evaluation of South African plants for insecticidal properties

CSIR Research Space (South Africa)

Maharaj, R

2006-02-01

Full Text Available Flacourtia indica Maytenus senegalensis Psiadia punctulata Ximenia caffra Dodonaea viscosa Helichrysum species Nuxia floribunda Pterocarpus angolensis Euphorbia tirucalli Lippia javanica Parinari curatellifolia Rauvolfia caffra Hyptis pectinata Parinari... crispus Schefflera umbellifera Rauvolfia caffra Schefflera umbellifera Strychnos madagascariensis Ricinus communis Spirostachys africana Vangueria infausta Rumex crispus Strychnos potatorum Warburgia salutaris Schefflera umbellifera Vernonia myriantha...

Physical and ionic characteristics in water soluble fraction (WSF) of ...

African Journals Online (AJOL)

The values of ionic and physical characteristics at 25, 50 and 100% water soluble fraction (WSF) of Olomoro well-head crude oil before and after exposure to Azolla africana were investigated. The WSF values before and after exposure to the plants showed that more ions were available after the introduction of the test plant.

Browse Title Index

African Journals Online (AJOL)

Items 51 - 100 of 263 ... Vol 5, No 2 (2006), Blood glucose level and lipid profile in rats fed on Treculia Africana (Breadfruit) diet: A sub-chronic study, Abstract. OO Okwari, OE Ofem, ... Vol 9, No 2 (2010), Comparative Effect of Fresh, Thermoxidized and Irradiated Oil on Gastric Acid Secretion and Cytoprotection in Rats, Abstract.

Assessment of Quality and Safety of Street-vended Fried West ...

African Journals Online (AJOL)

This study was carried out to assess the quality and safety of street-vended fried West African ilisha (Ilisha africana) from major markets in Ibadan, Oyo State, Nigeria. A total number of 100 fried fish samples obtained from ten major markets in Ibadan, Oyo State, Nigeria were analysed in the laboratory for: proximate ...

Antifungal and antibacterial activities of the ethanolic and aqueous ...

African Journals Online (AJOL)

SERVER

2007-07-18

Jul 18, 2007 ... psoriasis and eczema, through to the more serious disease like leprosy, syphilis and skin cancer (Burkill,. 1985). Previous studies of the fruits of K. africana showed some antibacterial activity (Grace et al., 2002). However there is no report on the antibacterial and antifungal properties of the stem bark of this ...

umlalazi estuary

African Journals Online (AJOL)

in an increase in the fauna associated with mangrove swamps and a decrease in the ... Zo%gica Africana 2 (1): 1-24. 1. R ep rod u ced b y Sa b in et G a tew a. y u n d ...... is remarkably similar to the UmIalazi in topography, fauna and flora.

Taking Flight Internationally

Science.gov (United States)

Roach, Ronald

2007-01-01

This article describes how Dr. Ben Vinson III, the new director of the Center for Africana Studies at Johns Hopkins University and a specialist in Latin American history, is strengthening the center's internationalist orientation. While it took more than three decades for Johns Hopkins University to approve a Black studies program in its arts and…

Practical integrated simulation systems for coupled numerical simulations in parallel

Energy Technology Data Exchange (ETDEWEB)

Osamu, Hazama; Zhihong, Guo [Japan Atomic Energy Research Inst., Centre for Promotion of Computational Science and Engineering, Tokyo (Japan)

2003-07-01

In order for the numerical simulations to reflect 'real-world' phenomena and occurrences, incorporation of multidisciplinary and multi-physics simulations considering various physical models and factors are becoming essential. However, there still exist many obstacles which inhibit such numerical simulations. For example, it is still difficult in many instances to develop satisfactory software packages which allow for such coupled simulations and such simulations will require more computational resources. A precise multi-physics simulation today will require parallel processing which again makes it a complicated process. Under the international cooperative efforts between CCSE/JAERI and Fraunhofer SCAI, a German institute, a library called the MpCCI, or Mesh-based Parallel Code Coupling Interface, has been implemented together with a library called STAMPI to couple two existing codes to develop an 'integrated numerical simulation system' intended for meta-computing environments. (authors)

Communication Systems Simulation Laboratory (CSSL): Simulation Planning Guide

Science.gov (United States)

Schlesinger, Adam

2012-01-01

The simulation process, milestones and inputs are unknowns to first-time users of the CSSL. The Simulation Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their engineering personnel in simulation planning and execution. Material covered includes a roadmap of the simulation process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, facility interfaces, and inputs necessary to define scope, cost, and schedule are included as an appendix to the guide.

La ruta Atlántica del pensamiento afrodescendiente. Hacia un referencial teórico afro sobre la historia de la trata transatlántica, la esclavitud perpetua y la invención del sofisma racial

Directory of Open Access Journals (Sweden)

Christianne Silva Vasconcellos

2014-01-01

Full Text Available Este artículo tiene el propósito de presentar un referencial teórico escrito en las rutas del Atlántico por personas africanas y afrodescendientes, entre los siglos XVIII y XIX. En particular se abordará la interpretación de tres procesos históricos relevantes en la historia de América: la trata transatlántica, la esclavitud perpetua y la invención y uso del sofisma racial. Las autoras y autores que aquí señalaremos teorizaron las experiencias que atravesaron en el seno de sociedades esclavistas y racialistas en América, el Caribe y Europa a punto de forjar un pensamiento propio que está registrado en cartas, poemas, novelas, autobiografías y tesis académicas. Lo que aquí se propone es que estas versiones conforman un referencial teórico capaz de descolonizar la comprensión de la historia de la Diáspora Africana en los centros educativos y académicos en América.

Real time simulation techniques in Taiwan - Maanshan compact simulator

International Nuclear Information System (INIS)

Liang, K.-S.; Chuang, Y.-M.; Ko, H.-T.

2004-01-01

Recognizing the demand and potential market of simulators in various industries, a special project for real time simulation technology transfer was initiated in Taiwan in 1991. In this technology transfer program, the most advanced real-time dynamic modules for nuclear power simulation were introduced. Those modules can be divided into two categories; one is modeling related to catch dynamic response of each system, and the other is computer related to provide special real time computing environment and man-machine interface. The modeling related modules consist of the thermodynamic module, the three-dimensional core neutronics module and the advanced balance of plant module. As planned in the project, the technology transfer team should build a compact simulator for the Maanshan power plant before the end of the project to demonstrate the success of the technology transfer program. The compact simulator was designed to support the training from the regular full scope simulator which was already equipped in the Maanshan plant. The feature of this compact simulator focused on providing know-why training by the enhanced graphic display. The potential users were identified as senior operators, instructors and nuclear engineers. Total about 13 important systems were covered in the scope of the compact simulator, and multi-graphic displays from three color monitors mounted on the 10 feet compact panel were facilitated to help the user visualize detailed phenomena under scenarios of interest. (author)

Displays and simulators

Science.gov (United States)

Mohon, N.

A 'simulator' is defined as a machine which imitates the behavior of a real system in a very precise manner. The major components of a simulator and their interaction are outlined in brief form, taking into account the major components of an aircraft flight simulator. Particular attention is given to the visual display portion of the simulator, the basic components of the display, their interactions, and their characteristics. Real image displays are considered along with virtual image displays, and image generators. Attention is given to an advanced simulator for pilot training, a holographic pancake window, a scan laser image generator, the construction of an infrared target simulator, and the Apollo Command Module Simulator.

Simulated experiments

International Nuclear Information System (INIS)

Bjerknes, R.

1977-01-01

A cybernetic model has been developed to elucidate some of the main principles of the growth regulation system in the epidermis of the hairless mouse. A number of actual and theoretical biological experiments have been simulated on the model. These included simulating the cell kinetics as measured by pulse labelling with tritiated thymidine and by continuous labelling with tritiated thymidine. Other simulated experiments included steady state, wear and tear, painting with a carcinogen, heredity and heredity and tumour. Numerous diagrams illustrate the results of these simulated experiments. (JIW)

Desktop Modeling and Simulation: Parsimonious, yet Effective Discrete-Event Simulation Analysis

Science.gov (United States)

Bradley, James R.

2012-01-01

This paper evaluates how quickly students can be trained to construct useful discrete-event simulation models using Excel The typical supply chain used by many large national retailers is described, and an Excel-based simulation model is constructed of it The set of programming and simulation skills required for development of that model are then determined we conclude that six hours of training are required to teach the skills to MBA students . The simulation presented here contains all fundamental functionallty of a simulation model, and so our result holds for any discrete-event simulation model. We argue therefore that Industry workers with the same technical skill set as students having completed one year in an MBA program can be quickly trained to construct simulation models. This result gives credence to the efficacy of Desktop Modeling and Simulation whereby simulation analyses can be quickly developed, run, and analyzed with widely available software, namely Excel.

The panel-free simulator

International Nuclear Information System (INIS)

Lucas, G.

1990-01-01

This paper reports on a simulator which is a device which simulates a physical object for training purposes. Although effective tools, Simulators posses two primary limitations. First, due to the dynamic nature of the simulated object, the Simulator may require frequent modification to remain an accurate representation. When Simulators are upgraded, modifications often turn out to be expensive. Increasingly, Simulator upgrades are required by regulations, no matter how costly. The second limitation is the number of personnel that can utilize a Simulator simultaneously. Engineers, Instructors, and Students are frequently forced work second and third shifts to obtain Simulator time. A study of existing Simulators by the Power Plant Simulation Division of Link-Miles Corporation spawned a software development project. The purpose of this project was to minimize the limitations of existing Simulators by designing a system to enhance Simulator modifications and usage

Business process simulation

NARCIS (Netherlands)

Aalst, van der W.M.P.; Nakatumba, J.; Rozinat, A.; Russell, N.C.; Brocke, vom J.; Rosemann, M.

2010-01-01

Although simulation is typically considered as relevant and highly applicable, in reality the use of simulation is limited. Many organizations have tried to use simulation to analyze their business processes at some stage. However, few are using simulation in a structured and effective manner. This

Advances in Intelligent Modelling and Simulation Simulation Tools and Applications

CERN Document Server

Oplatková, Zuzana; Carvalho, Marco; Kisiel-Dorohinicki, Marek

2012-01-01

The human capacity to abstract complex systems and phenomena into simplified models has played a critical role in the rapid evolution of our modern industrial processes and scientific research. As a science and an art, Modelling and Simulation have been one of the core enablers of this remarkable human trace, and have become a topic of great importance for researchers and practitioners. This book was created to compile some of the most recent concepts, advances, challenges and ideas associated with Intelligent Modelling and Simulation frameworks, tools and applications. The first chapter discusses the important aspects of a human interaction and the correct interpretation of results during simulations. The second chapter gets to the heart of the analysis of entrepreneurship by means of agent-based modelling and simulations. The following three chapters bring together the central theme of simulation frameworks, first describing an agent-based simulation framework, then a simulator for electrical machines, and...

Controle químico da "ERGOT" (Claviceps africana Frederickson, Mantle & de Milliano ou doença-açucarada e das principais doenças foliares do sorgo (Sorghum bicolor (L. Moench Chemical control of "ERGOT"(Claviceps africana Frederickson, Mantle & de Milliano or sugary disease and the main foliar diseases of sorghum (Sorghum bicolor (L. Moench

Directory of Open Access Journals (Sweden)

Nicésio Filadelfo Janssen de Almeida Pinto

2003-08-01

Full Text Available O controle químico da "ergot" (Claviceps africana foi realizado em campo de produção de sementes do híbrido de sorgo granífero BR 304 (Sorghum bicolor (L. Moench., utilizando-se os fungicidas (g i.a./ha: captan (1250,0, fenarimol (80,0, trifenil hidróxido de estanho (166,7, prochloraz (450,0, chlorothalonil (1500,0, iprodione (750,0, azoxystrobin (150,0, thiabendazole (360,0, procimidone (750,0, ziram (1500,0 e tebuconazole (200,0. Parcelas sem aplicação de fungicida constituíram a testemunha. As pulverizações foram realizadas com pulverizador costal manual, com o jato dirigido para as panículas. O intervalo das aplicações dos fungicidas foi de 4 dias, a partir da antese. Aos 7 dias após o término das pulverizações, a porcentagem de panículas doentes variou 5,4 para o fungicida tebuconazole e 100,0% para a maioria dos demais tratamentos. Para a porcentagem de flores doentes por panícula, os valores variaram de 0,3% a 65,0% para o fungicida tebuconazole e testemunha, respectivamente. Não ocorreu diferença significativa entre as porcentagens de flores doentes por panículas nos tratamentos tebuconazole (0,3%, chlorothalonil (2,5% e prochloraz (3,0%, sendo esses os mais eficientes no controle da ergot. Adicionalmente, o fungicida mais eficiente no controle da antracnose foliar (Colletotrichum graminicola foi o prochloraz, ao passo que para a ferrugem (Puccinia purpurea e a cercosporiose (Cercospora fusimaculans, o maior controle foi obtido com o fungicida tebuconazole. Não houve aumento da germinação das sementes em nenhum dos tratamentos; entretanto, o aumento do peso de mil sementes foi significativo para os tratamentos com os fungicidas prochloraz, chlorotalonil e tebuconazole.The efficiency of fungicides in the control of sugar disease of sorghum (Sorghum bicolor (L. Moench. was evaluated in a seed production field of the sorghum hybrid BR 304. The following fungicides and doses (g a.i./ha were evaluated : captan (1250

SimulaTE: simulating complex landscapes of transposable elements of populations.

Science.gov (United States)

Kofler, Robert

2018-04-15

Estimating the abundance of transposable elements (TEs) in populations (or tissues) promises to answer many open research questions. However, progress is hampered by the lack of concordance between different approaches for TE identification and thus potentially unreliable results. To address this problem, we developed SimulaTE a tool that generates TE landscapes for populations using a newly developed domain specific language (DSL). The simple syntax of our DSL allows for easily building even complex TE landscapes that have, for example, nested, truncated and highly diverged TE insertions. Reads may be simulated for the populations using different sequencing technologies (PacBio, Illumina paired-ends) and strategies (sequencing individuals and pooled populations). The comparison between the expected (i.e. simulated) and the observed results will guide researchers in finding the most suitable approach for a particular research question. SimulaTE is implemented in Python and available at https://sourceforge.net/projects/simulates/. Manual https://sourceforge.net/p/simulates/wiki/Home/#manual; Test data and tutorials https://sourceforge.net/p/simulates/wiki/Home/#walkthrough; Validation https://sourceforge.net/p/simulates/wiki/Home/#validation. robert.kofler@vetmeduni.ac.at.

Combine Harvester Simulator

DEFF Research Database (Denmark)

Vilmann, Ole; Sørlie, James Arnold

1999-01-01

A simulator for training pilots in the operation of a modern high-tech combine harvester is presented. The new simulator application is based on DMI´s well-known DMS maritime simulator architecture. Two major challenges have been encountered in the development of the simulator: 1) interfacing the...

A new Helota-species from Kondué (Belgian Congo)

NARCIS (Netherlands)

Ritsema Cz., C.

1910-01-01

This new species belongs to the group of guineensis, Sjöstedti and africana 1) but is nearer to both the former than to the latter, having in the female-sex the apices of the elytra pointed, not obliquely truncate between the 3rd interstice and the suture. It differs however in the male-sex from

Mycoflora of Some Smoked Fish Varieties in Benin City Nigeria ...

African Journals Online (AJOL)

Rhizopus sp. and Trichoderma sp. in their order of decreasing frequency in all the fish samples. The highest mean mycoflora count (17.833 x103cfu) was recorded in Tilapia sp., while the lowest mean value (11.16 x103cfu) was recorded in Drepane africana. Aspergillus species are known to produce aflatoxins which are ...

Sharks caught in the protective gill nets off KwaZulu-Natal, South ...

African Journals Online (AJOL)

Between 1980 and 2001, a total of 661 African angel sharks Squatina africana was caught in the protective nets off KwaZulu-Natal, South Africa. The mean annual catch was 30 sharks (range = 11–69, SD = 12.4), with no trend in catch rate over the study period. Individuals were caught throughout the year and through ...

Research Paper ISSN 0189-6016©2009

African Journals Online (AJOL)

AJTCAM

They were randomized into six groups of six rats each. Food was withdrawn 24 hrs and water 2hr before the commencement of experiment (Alphin and Ward, 1967). Group 1 (control) received only indomethacin (Sigma, 60mg/kg p.o. dissolved in 5% Na2Co3); Groups 2- 4 were pretreated with Lasianthera africana extract ...

Evolution récente de la population, de l'occupation des sols et de la ...

African Journals Online (AJOL)

Cisse

on assiste depuis peu aux premières plantations par les populations d'espèces arborées locales. : Prosopis africana, Khaya senegalensis,. Adansonia digitata, Parkia biglobosa ou importées : Eucalytus camaldulensis, Prosopis juliflora. Ces plantations sont pour la plupart effectuées à l'intérieur et le long de la clôture de.

Circulation of shelf waters in the KwaZulu-Natal Bight, South Africa ...

African Journals Online (AJOL)

Ship-based acoustic Doppler current profiler (S-ADCP) technology, used in survey mode, has enabled nearsynoptic views of the in situ 3-D current field in the KwaZulu-Natal (KZN) Bight to be elucidated for the first time. Data acquired by the research vessels RS Africana and RS Algoa in June 2005, September 2007, March ...

LOFT Engineering Simulator

International Nuclear Information System (INIS)

Venhuizen, J.R.

1982-02-01

The LOFT Engineering Simulator was developed to supply plant equivalent data for evaluating graphic aids and advanced control concepts for nuclear plant operators. The Simulator, a combination of hardware and software, combines some of the features of best estimate (safety analysis) computer codes with reactor operator training simulators. The LOFT Engineering Simulator represents an attempt to develop a simulation with sufficient physical detail (solution of the conservation equations) for moderate accident simulation, but which will still run in real time and provide an interface for the operator to interact with the model. As a result of this combination, a real time simulation of the LOFT plant has been developed which yields realistic transient results. These data can be used for evaluating reactor control room aids such as Safety Parameter Displays and Janus Predictive Displays

Visualization and simulation techniques for surgical simulators using actual patient's data.

Science.gov (United States)

Radetzky, Arne; Nürnberger, Andreas

2002-11-01

Because of the increasing complexity of surgical interventions research in surgical simulation became more and more important over the last years. However, the simulation of tissue deformation is still a challenging problem, mainly due to the short response times that are required for real-time interaction. The demands to hard and software are even larger if not only the modeled human anatomy is used but the anatomy of actual patients. This is required if the surgical simulator should be used as training medium for expert surgeons rather than students. In this article, suitable visualization and simulation methods for surgical simulation utilizing actual patient's datasets are described. Therefore, the advantages and disadvantages of direct and indirect volume rendering for the visualization are discussed and a neuro-fuzzy system is described, which can be used for the simulation of interactive tissue deformations. The neuro-fuzzy system makes it possible to define the deformation behavior based on a linguistic description of the tissue characteristics or to learn the dynamics by using measured data of real tissue. Furthermore, a simulator for minimally-invasive neurosurgical interventions is presented that utilizes the described visualization and simulation methods. The structure of the simulator is described in detail and the results of a system evaluation by an experienced neurosurgeon--a quantitative comparison between different methods of virtual endoscopy as well as a comparison between real brain images and virtual endoscopies--are given. The evaluation proved that the simulator provides a higher realism of the visualization and simulation then other currently available simulators. Copyright 2002 Elsevier Science B.V.

Trends in simulation and the Krsko full scope simulator

International Nuclear Information System (INIS)

Boire, R.; Chatlani, M.

1998-01-01

The nuclear power plant simulation industry is a fast-paced industry yielding continual development as a result of innovations in technology and customer requirements. This paper will discuss the current trends in simulator requirements, the status of simulation technology and the expected future developments, particularly in the context of the NPP Krsko full scope simulator. CAE Electronics has been awarded the contract for the design, construction, integration, testing and commissioning of the NPP Krsko full scope simulator (KFSS) by Nuklearna elektrarna Krsko (NEK). KFSS, as an integral part of the NPP Krsko Modernization plan, has been the subject of an extensive procurement process. KFSS will also take into account the steam generator replacement and plant uprate projects which will be delivered to provide initial training in the modernized plant configuration. As a result, the completed KFSS will meet NEK's goals for reliable training in safe plant operation as well as the licensing requirements of the Slovenian Nuclear Safety Administration. KFSS will be a state-of-the-art facility featuring high fidelity process and control models, proven technology and superior maintainability that will push the envelope of traditional simulator uses. In addition to serving its role as a high quality training vehicle, KFSS will be used for engineering purposes including procedure development and validation, optimization of plant operation and study and validation of plant modifications. KFSS models will be built for the most part with CAE's ROSE TM toolset. ROSE, is a component-based, visual programming environment for the creation, testing, integration and management of simulator models and supporting virtual panels. The NSSS will be simulated using the ANTHEM two-phase drift flux model, while be simulated using the COMET two-group, three-dimensional model. Software design and testing will be supported by an extensive series of quality procedures throughout the software

Pyro shock simulation: Experience with the MIPS simulator

Science.gov (United States)

Dwyer, Thomas J.; Moul, David S.

1988-01-01

The Mechanical Impulse Pyro Shock (MIPS) Simulator at GE Astro Space Division is one version of a design that is in limited use throughout the aerospace industry, and is typically used for component shock testing at levels up to 10,000 response g's. Modifications to the force imput, table and component boundary conditions have allowed a range of test conditions to be achieved. Twelve different designs of components with weights up to 23 Kg are in the process or have completed qualification testing in the Dynamic Simulation Lab at GE in Valley Forge, Pa. A summary of the experience gained through the use of this simulator is presented as well as examples of shock experiments that can be readily simulated at the GE Astro MIPS facility.

Recent advancements in medical simulation: patient-specific virtual reality simulation.

Science.gov (United States)

Willaert, Willem I M; Aggarwal, Rajesh; Van Herzeele, Isabelle; Cheshire, Nicholas J; Vermassen, Frank E

2012-07-01

Patient-specific virtual reality simulation (PSVR) is a new technological advancement that allows practice of upcoming real operations and complements the established role of VR simulation as a generic training tool. This review describes current developments in PSVR and draws parallels with other high-stake industries, such as aviation, military, and sports. A review of the literature was performed using PubMed and Internet search engines to retrieve data relevant to PSVR in medicine. All reports pertaining to PSVR were included. Reports on simulators that did not incorporate a haptic interface device were excluded from the review. Fifteen reports described 12 simulators that enabled PSVR. Medical procedures in the field of laparoscopy, vascular surgery, orthopedics, neurosurgery, and plastic surgery were included. In all cases, source data was two-dimensional CT or MRI data. Face validity was most commonly reported. Only one (vascular) simulator had undergone face, content, and construct validity. Of the 12 simulators, 1 is commercialized and 11 are prototypes. Five simulators have been used in conjunction with real patient procedures. PSVR is a promising technological advance within medicine. The majority of simulators are still in the prototype phase. As further developments unfold, the validity of PSVR will have to be examined much like generic VR simulation for training purposes. Nonetheless, similar to the aviation, military, and sport industries, operative performance and patient safety may be enhanced by the application of this novel technology.

Discrete-Event Simulation

Directory of Open Access Journals (Sweden)

Prateek Sharma

2015-04-01

Full Text Available Abstract Simulation can be regarded as the emulation of the behavior of a real-world system over an interval of time. The process of simulation relies upon the generation of the history of a system and then analyzing that history to predict the outcome and improve the working of real systems. Simulations can be of various kinds but the topic of interest here is one of the most important kind of simulation which is Discrete-Event Simulation which models the system as a discrete sequence of events in time. So this paper aims at introducing about Discrete-Event Simulation and analyzing how it is beneficial to the real world systems.

A prospective, randomized study addressing the need for physical simulation following virtual simulation

International Nuclear Information System (INIS)

Valicenti, Richard K.; Waterman, Frank M.; Corn, Benjamin W.; Curran, Walter J.

1997-01-01

Purpose: To accurately implement a treatment plan obtained by virtual or CT simulation, conventional or physical simulation is still widely used. To evaluate the need for physical simulation, we prospectively randomized patients to undergo physical simulation or no additional simulation after virtual simulation. Methods and Materials: From July 1995 to September 1996, 75 patients underwent conformal four-field radiation therapy planning for prostate cancer with a commercial grade CT simulator. The patients were randomized to undergo either port filming immediately following physical simulation or port filming alone. The precision of implementing the devised plan was evaluated by comparing simulator radiographs and/or port films against the digitally reconstructed radiographs (DRRs) for x, y, and z displacements of the isocenter. Changes in beam aperture were also prospectively evaluated. Results: Thirty-seven patients were randomized to undergo physical simulation and first day port filming, and 38 had first day treatment verification films only without a physical simulation. Seventy-eight simulator radiographs and 195 first day treatment port films were reviewed. There was no statistically significant reduction in treatment setup error (>5 mm) if patients underwent physical simulation following virtual simulation. No patient required a resimulation, and there was no significant difference in changes of beam aperture. Conclusions: Following virtual simulation, physical simulation may not be necessary to accurately implement the conformal four-field technique. Because port filming appears to be sufficient to assure precise and reliable execution of a devised treatment plan, physical simulation may be eliminated from the process of CT based planning when virtual simulation is available

Discrete-Event Simulation

OpenAIRE

Prateek Sharma

2015-01-01

Abstract Simulation can be regarded as the emulation of the behavior of a real-world system over an interval of time. The process of simulation relies upon the generation of the history of a system and then analyzing that history to predict the outcome and improve the working of real systems. Simulations can be of various kinds but the topic of interest here is one of the most important kind of simulation which is Discrete-Event Simulation which models the system as a discrete sequence of ev...

Simulation of Electrical Grid with Omnet++ Open Source Discrete Event System Simulator

Directory of Open Access Journals (Sweden)

Sőrés Milán

2016-12-01

Full Text Available The simulation of electrical networks is very important before development and servicing of electrical networks and grids can occur. There are software that can simulate the behaviour of electrical grids under different operating conditions, but these simulation environments cannot be used in a single cloud-based project, because they are not GNU-licensed software products. In this paper, an integrated framework was proposed that models and simulates communication networks. The design and operation of the simulation environment are investigated and a model of electrical components is proposed. After simulation, the simulation results were compared to manual computed results.

Full-scope training simulators

International Nuclear Information System (INIS)

Ugedo, E.

1986-01-01

The following topics to be covered in this report are: Reasons justifying the use of full-scope simulators for operator qualification. Full-scope simulator description: the control room, the physical models, the computer complex, the instructor's console. Main features of full-scope simulators. Merits of simulator training. The role of full-scope simulators in the training programs. The process of ordering and acquiring a full-scope simulator. Maintaining and updating simulator capabilities. (orig./GL)

Simulation in bronchoscopy

DEFF Research Database (Denmark)

Nilsson, Philip Mørkeberg; Naur, Therese Maria Henriette; Clementsen, Paul Frost

2017-01-01

, and the training should be structured as distributed practice with mastery learning criteria (ie, training until a certain level of competence is achieved). Dyad practice (training in pairs) is possible and may increase utility of available simulators. Trainee performance should be assessed with assessment tools......Objective: To provide an overview of current literature that informs how to approach simulation practice of bronchoscopy and discuss how findings from other simulation research can help inform the use of simulation in bronchoscopy training. Summary: We conducted a literature search on simulation...

Simulation tools

CERN Document Server

Jenni, F

2006-01-01

In the last two decades, simulation tools made a significant contribution to the great progress in development of power electronics. Time to market was shortened and development costs were reduced drastically. Falling costs, as well as improved speed and precision, opened new fields of application. Today, continuous and switched circuits can be mixed. A comfortable number of powerful simulation tools is available. The users have to choose the best suitable for their application. Here a simple rule applies: The best available simulation tool is the tool the user is already used to (provided, it can solve the task). Abilities, speed, user friendliness and other features are continuously being improved—even though they are already powerful and comfortable. This paper aims at giving the reader an insight into the simulation of power electronics. Starting with a short description of the fundamentals of a simulation tool as well as properties of tools, several tools are presented. Starting with simplified models ...

DeepSimulator: a deep simulator for Nanopore sequencing

KAUST Repository

Li, Yu; Han, Renmin; Bi, Chongwei; Li, Mo; Wang, Sheng; Gao, Xin

2017-01-01

or assembled contigs, we simulate the electrical current signals by a context-dependent deep learning model, followed by a base-calling procedure to yield simulated reads. This workflow mimics the sequencing procedure more naturally. The thorough experiments

Analog reactor simulator RAS; Reaktorski analogni simulator RAS

Energy Technology Data Exchange (ETDEWEB)

Radanovic, Lj; Bingulac, S; Popovic, D [The Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

1961-07-01

Analog computer RAS was designed as a nuclear reactor simulator, but it can be simultaneously used for solving a number of other problems. This paper contains a brief description of the simulator parts and their principal characteristics.

Numerical simulation of collision-free plasma using Vlasov hybrid simulation

International Nuclear Information System (INIS)

Nunn, D.

1990-01-01

A novel scheme for the numerical simulation of wave particle interactions in space plasmas has been developed. The method, termed VHS or Vlasov Hybrid Simulation, is applicable to hot collision free plasmas in which the unperturbed distribution functions is smooth and free of delta function singularities. The particle population is described as a continuous Vlasov fluid in phase space-granularity and collisional effects being ignored. In traditional PIC/CIC codes the charge/current due to each simulation particle is assigned to a fixed spatial grid. In the VHS method the simulation particles sample the Vlasov fluid and provide information about the value of distribution function (F(r,v) at random points in phase space. Values of F are interpolated from the simulation particles onto a fixed grid in velocity/position or phase space. With distribution function defined on a phase space grid the plasma charge/current field is quickly calculated. The simulation particles serve only to provide information, and thus the particle population may be dynamic. Particles no longer resonant with the wavefield may be discarded from the simulation, and new particles may be inserted into the Vlasov fluid where required

A prospective study to determine the need for physical simulation following virtual simulation

International Nuclear Information System (INIS)

Valicenti, R.K.; Waterman, F.M.; Corn, B.W.; Sweet, J.; Curran, W.J.

1996-01-01

Purpose: Virtual simulation is CT based planning utilizing computed digitally reconstructed radiographs (DRRs) in a manner similar to conventional fluoroscopic simulation. However, conventional or physical simulation is still widely used to assure precise implementation of the devised plan. To evaluate the need for performing physical simulation, we prospectively studied patients undergoing virtual simulation who either had or did not have a subsequent physical simulation. Materials and Methods: From July, 1995 to February, 1996, 48 patients underwent conformal 4-field radiation therapy for prostate cancer using a commercial grade spiral CT simulator. All patients were immobilized in a foam body cast and positioned by using a fiducial laser marking system. Following prostate and seminal vesicle definition on a slice-by-slice basis, virtual simulation was performed. The isocenter defined by this process was marked on both the patient and the immobilization device before leaving the CT simulator room. The isocenter position of the devised plan was evaluated by three verification methods: physical simulation, first day treatment port filming, and port filming immediately following physical simulation. Simulator radiographs and port films were compared against DRRs for x, y, and z deviations of the isocenter. These deviations were used as a measure of the implementation precision achieved by each verification method. Results: Thirty-seven patients underwent physical simulation and first day port filming. Eleven had first day treatment verification films only and never had a physical simulation. A total of 79 simulator radiographs and 126 first day treatment port films were reviewed. The tabulation of all deviations is as follows: There was significantly more setup error (≥ 5 mm) observed when the devised treatment was implemented in the treatment room as opposed to the physical simulator. The physical simulator did not lead to a significant reduction in setup error

Shock Mechanism Analysis and Simulation of High-Power Hydraulic Shock Wave Simulator

Directory of Open Access Journals (Sweden)

Xiaoqiu Xu

2017-01-01

Full Text Available The simulation of regular shock wave (e.g., half-sine can be achieved by the traditional rubber shock simulator, but the practical high-power shock wave characterized by steep prepeak and gentle postpeak is hard to be realized by the same. To tackle this disadvantage, a novel high-power hydraulic shock wave simulator based on the live firing muzzle shock principle was proposed in the current work. The influence of the typical shock characteristic parameters on the shock force wave was investigated via both theoretical deduction and software simulation. According to the obtained data compared with the results, in fact, it can be concluded that the developed hydraulic shock wave simulator can be applied to simulate the real condition of the shocking system. Further, the similarity evaluation of shock wave simulation was achieved based on the curvature distance, and the results stated that the simulation method was reasonable and the structural optimization based on software simulation is also beneficial to the increase of efficiency. Finally, the combination of theoretical analysis and simulation for the development of artillery recoil tester is a comprehensive approach in the design and structure optimization of the recoil system.

Developing Software Simulations

Directory of Open Access Journals (Sweden)

Tom Hall

2007-06-01

Full Text Available Programs in education and business often require learners to develop and demonstrate competence in specified areas and then be able to effectively apply this knowledge. One method to aid in developing a skill set in these areas is through the use of software simulations. These simulations can be used for learner demonstrations of competencies in a specified course as well as a review of the basic skills at the beginning of subsequent courses. The first section of this paper discusses ToolBook, the software used to develop our software simulations. The second section discusses the process of developing software simulations. The third part discusses how we have used software simulations to assess student knowledge of research design by providing simulations that allow the student to practice using SPSS and Excel.