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The choice of tree species planted with cacao trees is essential for ensuring the efficiency and sustainability of cacao farming systems. This raises the question of the long-term impact of associated tree legumes (ATLs) on cacao bean yields and biomass accumulation. This study was carried out in accordance with four-block randomised experimental design in Divo (Ivory Coast, West Africa). The study involved cacao-Albizia lebbeck (Cacao-Alb) and cacao-Acacia mangium (Cacao-Aca) intercrops and unshaded cacao plots (Control). After 20 years of intercropping, we assessed cacao dendrometry (height, circumference, biomass, and biomass C-stock) and production (number of pods per tree and bean yield at the plot level) as well as soil fertility (soil organic matter (SOM) concentration) at various distances from ATLs (D1:0–1.75 m; D2:3.25–5 m; D3:7–9 m). The distance from the ATLs had no significant effect on the measured cacao dendrometric parameters, except for cacao height. In contrast, the Cacao-Aca association had a negative impact on the SOM concentration (−22%), cacao tree height (−6.15%), and productivity parameters (biomass: −12.4%; bean yield: −43%). However, Cacao-Alb and the Control had no significant differences in terms of SOM, tree biomass, or bean production. Intercropping cacao with the tested tree legumes did not enhance cacao productivity and, in some cases, hindered it, depending on the ATL species. This study highlighted the importance of identifying appropriate shade tree legume species that could be promoted in cacao-based agroforestry systems.
The reproductive activity of feral male mice on an island of the sub-Antarctic Kerguelen archipelago was influenced by biological factors depending on periods within the breeding season. After having controlled host reproductive activity indices for body size, i.e. age, and body condition effects, Syphacia obvelata prevalence did not vary with host reproductive status or age either during the beginning or the middle–end of the reproductive season. Considering the beginning of the breeding season, worm abundance was more pronounced in males the year following a strong winter crash of the population than in years when high over wintering survival occurred. During the middle–end of the breeding season, males with the highest reproductive status were more infected than males with a lower reproductive status in years when oldest individuals dominated the population. It is suggested that this situation was due to an endocrine related increased host susceptibility partly influenced by a change in the age structure of the population, and that an increase in worm transmission was not directly related to male activity concurrent with reproductive status, nor to population density.
Beninese smallholders associate food crops and cash crops with immature oil palms to reduce field maintenance costs and gain income before the palms reach productive phase. Little is known about the effects of these crops on the nutritional status and growth of the palms in their immature phase even though the yield of adult palms can be affected by the management practices during this phase. The objective of this study was to evaluate the most common oil palm-based intercropping systems found in southern Benin in terms of nutritional status and growth of the palm. Within 15 oil palm farms, we compared 15 immature oil palm fields where the crop succession associated with the oil palms was dominated by maize, cassava, tomato, and pineapple. The nutrient concentrations in the soil and the palm leaves, and growth indicators were measured at the end of the immature phase. We found that the palm growth indicators were the lowest in the successions with pineapple. N and P nutrition of the immature palms was satisfactory but K was deficient in all systems, especially in those with pineapple. The K levels in the soils and palm leaves were correlated. Rough field budgets comparing the amounts of N and K applied to the crop successions with their N and K exports from non-returning products indicated that soil indigenous K supply would be particularly depleted in the systems with pineapple. We concluded that the young oil palms were affected by the competition for K exerted by the crop successions with pineapple even though they were the most fertilized in the region. The high profitable crop is therefore associated with the lowest growth rates of the immature palms. The mineral fertilizer management in these oil palm temporary intercropping systems should be improved.
A class of graphs is bridge-addable if given a graph $G$ in the class, any graph obtained by adding an edge between two connected components of $G$ is also in the class. The authors recently proved a conjecture of McDiarmid, Steger, and Welsh stating that if ${\mathcal{G}}$ is bridge-addable and $G_{n}$ is a uniform $n$-vertex graph from ${\mathcal{G}}$, then $G_{n}$ is connected with probability at least $(1+o_{n}(1))e^{-1/2}$. The constant $e^{-1/2}$ is best possible, since it is reached for the class of all forests.
In this paper, we prove a form of uniqueness in this statement: if ${\mathcal{G}}$ is a bridge-addable class and the random graph $G_{n}$ is connected with probability close to $e^{-1/2}$, then $G_{n}$ is asymptotically close to a uniform $n$-vertex random forest in a local sense. For example, if the probability converges to $e^{-1/2}$, then $G_{n}$ converges in the sense of Benjamini–Schramm to the uniformly infinite random forest $F_{\infty }$. This result is reminiscent of so-called “stability results” in extremal graph theory, the difference being that here the stable extremum is not a graph but a graph class.
Senegal is experiencing a rising obesity epidemic, due to the nutrition transition occurring in most African countries, and driven by sedentary behaviour and high-calorie dietary intake. In addition, the anthropological local drivers of the social valorization of processed high-calorie food and large body sizes could expose the population to obesity risk. This study aimed to determine the impact of these biocultural factors on the nutritional status of Senegalese adults. A mixed methods approach was used, including qualitative and quantitative studies. Between 2011 and 2013, fourteen focus group discussions (n=84) and a cross-sectional quantitative survey (n=313 women; n=284 men) of adults in three different socio-ecological areas of Senegal (rural: n=204; suburban: n=206; urban: n=187) were conducted. Dietary intake (Dietary Diversity Scores), physical activity (International Physical Activity Questionnaire), body weight norms (Body Size Scale), weight and health statuses (anthropometric measures and blood pressure) were measured. Middle-aged and older Senegalese women were found to value overweight/obesity more than younger Senegalese in all regions. In addition, young urban/suburban adults had a tendency for daily snacking whilst urban/suburban adults tended to be less physically active and had higher anthropometric means. A binary logistic regression model showed that being female, older, living in urban/suburban areas and valuing larger body size were independently associated with being overweight/obese, but not high-calorie diet. Univariate analyses showed that lower physical activity and higher socioeconomic status were associated with being overweight/obese. Finally, overweight/obesity, which is low in men, is associated with hypertension in the total sample. The nutrition transition is currently underway in Senegal’s urban/suburban areas, with older women being more affected. Since several specific biocultural factors jointly contribute to this phenomenon, the study’s findings suggest the need for local public health interventions that target women and which account for the anthropological specificities of the Senegalese population.
A ground-based radar has been used successfully for monitoring calving events and velocities at Kronebreen, Svalbard, for two test seasons in 2007 and 2008. We use daily terrestrial optical photogrammetry and continuous visual observation to validate the interpretation of a 116 hour ground-based radar amplitude of return signal data recorded from 26 to 30 August 2008. The radar was placed –4 km from the glacier. It measured at high temporal rate (2 Hz) and the antenna lobe covered a width of –700 m of the front. The calving-front geometry was extracted from the optical images, and its effect on radar backscatter, together with the movement of the glacier, was identified in the plot of the amplitude of the radar return signal. Calving events were detected applying an automated change-detection technique to the radar dataset. This technique allowed us to detect 92% of the events that were observed during the same time. In this paper, we focus on the method rather than on data interpretation. However, future use of this method, combined with meteorological data, tides and ocean temperature, will be valuable for calving-process studies.
Calving activity at the termini of tidewater glaciers produces a wide range of iceberg sizes at irregular intervals. We present calving-event data obtained from continuous observations of the termini of two tidewater glaciers on Svalbard, and show that the distributions of event sizes and inter-event intervals can be reproduced by a simple calving model, focusing on the mutual interplay between calving and the destabilization of the glacier terminus. The event-size distributions of both the field and the model data extend over several orders of magnitude and resemble power laws. The distributions of inter-event intervals are broad, but have a less pronounced tail. In the model, the width of the size distribution increases with the calving susceptibility of the glacier terminus, a parameter measuring the effect of calving on the stress in the local neighborhood of the calving region. Inter-event interval distributions, in contrast, are insensitive to the calving susceptibility. Above a critical susceptibility, small perturbations of the glacier result in ongoing self-sustained calving activity. The model suggests that the shape of the event-size distribution of a glacier is informative about its proximity to this transition point. Observations of rapid glacier retreats can be explained by supercritical self-sustained calving.
Breed risk status assessment methods are key components of country-based early warning and response systems. In this study, a multi-indicator method was developed to assess the risk status of livestock populations. Six indicators were used: (i) the current number of breeding females; (ii) the change in the number of breeding females over the last 5 years or generations (depending on the species); (iii) percentage of cross-breeding; (iv) effective population size; (v) breeders organization and technical support; and (vi) socio-economic context. To make these indicators comparable, observed values were converted into scores on a six-point scale (from 0 = no threat to 5 = maximum threat); a specific conversion method was used for each indicator. For each breed, the different scores were analysed graphically and an overall score was calculated by averaging the six separate indicator scores. This approach was applied to 178 French local breeds, belonging to ten different species: horse, donkey, goat, pig, chicken, turkey, goose and Pekin duck. A large percentage of local breeds were found to be at risk to be lost for farming, although the results were species dependent. All local equine and pig breeds, as well as almost all local poultry breeds appeared to be endangered. About 80 percent of local goat and cattle breeds, and half local sheep breeds were also found to be at risk. The usefulness of this method with regards to conservation strategies and public policy is discussed.
We show that the diameter diam(Gn) of a random labelled connected planar graph with n vertices is equal to n1/4+o(1), in probability. More precisely, there exists a constant c > 0 such that
Integrated crop–livestock systems in the tropical region are diverse and not well characterized. To better understand the conditions and potential of these systems, we characterized the spatial and social arrangement of integrated systems within a landscape context. Integrated systems are defined by biomass and nutrient flows, linking crop, livestock and human components of agriculture. The landscape is defined within a spatial framework of these flows. To understand the diversity of integrated systems in the tropics, we characterized three case study areas: Southern Mali, Brazilian Cerrados and Amazon frontier. Methodology was based on historical and descriptive approaches of these cases, mobilizing interdisciplinary knowledge of a large research team. This provided a retrospective view to discuss four key points about the future of integrated systems in the tropics: (i) importance of landscape structure for conception and adaptation of the integrated systems; (ii) key role of local institutions in managing such integrated systems; (iii) trade-offs between external and internal resources; and (iv) role of nitrogen to improve system efficiency. This paper concludes with the relevance of social sciences in the further development of integrated systems.
We observe the heat flux exchanged by the hot tip of a scanning thermal microscope, which is an instrument based on the atomic force microscope. We first vary the pressure in order to analyze the impact on the hot tip temperature. Then the distance between the tip and a cold sample is varied down to few nanometers, in order to reach the ballistic regime. We observe the cooling of the tip due to the tip-sample heat flux and compare it to the current models in the literature.
Scanning Thermal Microscopy measurements with a resistive microprobe electrically heated were performed for different probe temperatures, for probe free in air and in contact with various specimens. The measured relative difference of Joule power dissipated in the probe when tip is in contact with a sample and when it is free in air is studied for different magnitude of the electrical current that heats the probe. A variation of this signal, never outlined before, is observed. A predictive modeling is used to explain these results and identify from the experimental data the global thermal conductance of the probe-sample thermal exchange for experiments performed in ambient conditions.
Treatment teams use different approaches for correcting the alveolar cleft sector of labio-palatal clefts. Age of patient, whether or not bone grafts are used, and the type of bone grafted are some of the differences. Our team performs a gingivoperioplasty with a graft of iliac cancellous bone on patients 4 to 6 years old. This procedure is carried out within the framework of orthodontic treatment designed to restore transverse dimension pre-operatively with a quad helix and to retain the expansion with 6 months of retention. The gingivoperioplasty is accomplished in a zone free of any scar tissue that might have resulted from a primary cheiloplasty followed by closure of the palatal cleft. In our view all teams must eventually utilize cone beam X-rays for their radiographic evaluations because they are the only tool that provides results of objective analysis that are of high quality and have demanded a very low level of radiation.
Parents want their children’s’ faces, the most visible part of their bodies, one that marks their identity throughout life, to be perfect. To satisfy this understandably urgent desire, a high quality of primary treatment for cleft lip and palate is essential and must satisfy a double objective: restore normal morphology and normal function. The functional, morphological, and esthetic prognoses depend on the character of the defect, whether it stands alone or is associated in a syndrome with other malformations. Important sequellae flow from the quality of the initial repair, as a consequence of the surgery and other therapies as well as from the deformity itself.
Before the year 2000, the Maxillo-facial and Plastic Surgery Service at the Armand Trousseau Hospital of the Pierre and Marie Curie Faculty of Medicine adhered to the protocol that Malek had described, making an initial repair of the soft palate at 3 months and then a cheiloplasty, with upper and lower triangles, and closure of the hard palate at 6 months. Since then we have adopted the more functional approach that Talmant described, integrating systematic nasal surgery and the type of lip surgery that Millard suggested without leaving any residual exposed bone after closure of the osseous cleft. We then perform gingivo-periosteal surgery with bone grafts on patients when they were between 4 and 6 years of age, after orthodontic therapy had been completed. This constitutes the last stage of primary treatment.
The therapeutic approach we have been using on our service, which has evolved of over the last 20 years, has come to define its principal objective as integration of extensive rehabilitation into the very first stages of our multi-disciplinary therapy so as to minimize the establishment of faulty functioning of phonation, lip competence, and ventilation while avoiding any intervention that would have a harmful impact on facial growth. This multi-disciplinary approach, which integrates surgical evaluation and protocol, is indispensable and fully justifies treatment of patients with cleft lip and palate at accredited centers.