Nutritional implications of staple food crop successions in Usambara,Tanzania

Archival and ethnographic research carried out in northeastern Tanzania provides evidence of significant changes in production and consumption of staple food crops between 1850 and the present. The banana, which provided the bulk of calories and other nutrients in precolonial times, has been successively replaced by Irish potatoes, maize, and cassava in different localities. The reasons for the adoption of each of these introduced crops are explored, and their implications for human nutrition in the area are discussed.     

A cladistic analysis of the Solatium sessile species group (section Geminata pro parte: Solanaceae)

The Solanum sessile species group is one of eight putatively monophyletic subgroups of the large and diverse Solanum section Geminata. The species group comprises ten species of mostly northern South American trees and shrubs. Characters and character states peculiar to Solanum are discussed in detail. A cladistic analysis of the sessile group yielded four equally parsimonious trees which represent two basic tree topologies. The consensus cladogram is composed of three main clades. Biogeographic analysis using the consensus tree revealed no components in common to the three clades. Possible geographical scenarios are discussed with reference to the geological history of northern South America.     

Managing uncertainty: a review of food system scenario analysis and modelling

Complex socio-ecological systems like the food system are unpredictable, especially to long-term horizons such as 2050. In order to manage this uncertainty, scenario analysis has been used in conjunction with food system models to explore plausible future outcomes. Food system scenarios use a diversity of scenario types and modelling approaches determined by the purpose of the exercise and by technical, methodological and epistemological constraints. Our case studies do not suggest Malthusian futures for a projected global population of 9 billion in 2050; but international trade will be a crucial determinant of outcomes; and the concept of sustainability across the dimensions of the food system has been inadequately explored so far. The impact of scenario analysis at a global scale could be strengthened with participatory processes involving key actors at other geographical scales. Food system models are valuable in managing existing knowledge on system behaviour and ensuring the credibility of qualitative stories but they are limited by current datasets for global crop production and trade, land use and hydrology. Climate change is likely to challenge the adaptive capacity of agricultural production and there are important knowledge gaps for modelling research to address.     

Live food production using batch culture and chemostat systems in Kuwait

A comparison of live food production using batch andchemostat systems between the facilities initiated in1988 and the re-establishment of new larger chemostatsystems, after Kuwaits liberation, is made. The livefood production dynamics achieved during the 1995–1996 spawning season of Shaem (Acanthopagrus latus)are discussed. Growth rate of the rotifers (Brachionusplicatilis) treated 24 h with a mixture of marinealgal species (Nannochloropsis, Isochrysis,Tetraselmis, Chlorella) plus other enrichment mediasuch as Super Selco, Protein Selco and Sanders priorto being supplied to the marine fish larvae isdiscussed. Rotifer production reached up to 2000 ×10⁶ individuals per day.     

Microbial and classical food webs: A visit to a hypertrophic lake

Abstract: Plankton community structure and fluxes of carbon for bacteria (production and bacterivory) were investigated in the urban, hypertrophic Lake Rodó (Uruguay) using a short time interval for sampling (5–15 d) during one year. The lake sustains a high phytoplankton biomass (up to 335 μg l⁻¹ chlorophyll a ) always dominated by the filamentous cyanobacteria Planktothrix agardhii . The zooplankton community was numerically dominated by rotifers and ciliates; cladocerans were rare during most of the year. The rotifer abundance was very high (up to 10⁵ individual l⁻¹), the bacterivorous Anuraeopsis fissa being the most abundant species. Predation rates of heterotrophic nanoflagellates (HNF) on bacteria (range: 31–130 bacteria HNF⁻¹ h⁻¹) were higher than those reported in the literature for field studies. A carbon budget showed that HNF can consume on average 91 and 76% of the bacterial carbon production in summer and winter, respectively. Bacterial turnover times are the lowest reported until now from field conditions (5 to 42 h). Consequently, bacterial carbon production was extremely high (72 to 1071 μg C l⁻¹ d⁻¹). Bacterial production was positively correlated to bacterial abundance but the relationship was significantly improved by the inclusion of temperature (82% variability explained). My results support the general trend for increased bacterial production with increasing trophic status, and suggest a lower energy transfer efficiency to higher trophic levels in hypertrophic lakes due to the many trophic interactions involved.     

Food web quantification using secondary production analysis: predaceous invertebrates of the snag habitat in a subtropical river

1. Secondary production was estimated for Plecoptera, Odonata and Megaloptera (mostly large predators) occurring on the snag habitat of a subtropical blackwater river in the southeastern U.S.A. Coastal Plain for 2 years. Production estimates and gut analyses were used in estimating species‐specific ingestion to construct a quantitative food web of the predator portion of the invertebrate assemblage. Neither basal resources (e.g. detritus) nor predaceous vertebrates (e.g. fishes) were considered in this analysis. A discharge‐specific model of snag‐habitat availability was used to convert values per m² of snag surface to values per m² of river bed.
2. These three orders included the major large predators on the snag habitat, as well as two detritivorous stoneflies. The major predators were the hellgrammite (Corydaluscornutus), five perlid stoneflies (Paragnetinakansensis, Perlestaplacida, Neoperlaclymene, Acroneuriaevoluta and Acroneuriaabnormis) and two dragonflies (Neurocorduliamolesta and Boyeriavinosa). The detritivores were Pteronarcysdorsata and Taeniopteryxlita.
3. Total predator production was high, but varied from only 7.1 to 7.4 g dry mass (DM) m^?2 y^?1 of snag surface (2.4–2.7 g DM m^?2 y^?1 of river bed) over two years. Corydalus was the largest predator and had the highest production (2.8–3.1 g DM m^?2 of snag surface). The most productive stoneflies were Perlesta (0.7–1.0 g DM m^?2 of snag surface) and Paragnetina (1.0–1.3 g DM m^?2 of snag surface). The most productive dragonfly was Neurocordulia (0.7–1.9 g DM m^?2 of snag surface). Production of the non‐predaceous stoneflies was 1.0–2.3 g DM m^?2 of snag surface. Production values per m² of river bed were 2–3.5 times lower than the values per m² snag surface.
4. Measurement of ingestion fluxes within the predator portion of the food web showed that predaceous invertebrates were primarily supported by chironomid and mayfly prey. However, the greatest consumption of chironomids and mayflies was by omnivorous hydropsychid caddisflies, which had a considerably higher production than the larger predators. There was a hierarchy of feeding with Corydalus as top predator consuming all other groups, followed in order by dragonflies, stoneflies and hydropsychids. Although the feeding hierarchy suggested the presence of four predatory trophic levels within the invertebrate assemblage, calculations of trophic position indicated there were less than two. With primary consumers (e.g. midges) having a trophic position of 2, Corydalus had a trophic position of only 3.5.
5. A relatively high fraction of invertebrate production was consumed by predaceous invertebrates, ranging from 9 to >100% for various primary consumer groups, with total consumption representing 52% of total production. Because these estimates do not include vertebrate consumption or emergence, it means that a high fraction of larval mortality is due to predation.     

Gastric emptying in Scyliorhinus canicula (L.): a comparison of surface-dependent and non-surface dependent models

The usefulness of both surface-dependent and non-surface-dependent models for describing the gastric emptying process in Scyliorhinus canicula (L.) was examined. In most cases the surface-dependent models produced better fits than did the non-surface-dependent models. The exponential model (non-surface-dependent) only adequately described gastric evacuation in the case of small prey items with thin exoskeletons. On the other hand, the exponential model was clearly better than the linear model in all cases. Prey size had little effect on digestion rate. However, the number of prey items ingested was an important factor influencing digestion.     

Wild gathered food plants in the European mediterranean: A comparative analysis

The Mediterranean basin has a long and multifaceted cultural history and harbors a high biodiversity. Epidemiological studies have drawn attention to certain traditional Mediterranean diets. However, wild gathered food species, which are an important, but fast disappearing element of these diets, so far have been largely neglected in scientific studies. In this study we compare ethnobotanical data obtained from field studies conducted in Southern Italy, Southern Spain, mainland Greece, and Crete resulting in the identification of a core group of 18 culinary used wild gathered plant species. This group comprises species likePapaver rhoeas L.,Sonchus asper L.,S. oleraceus L., andSilene vulgaris L. We argue that the culinary use of wild gathered weedy greens evolved together with the neolithization process, since this offered the necessary ecological niches for them to thrive, thereby enriching and securing the diets of European agriculturalists. Especially wild gathered Asteraceae species seem to form a sort of proto-nutraceutical, which accounts for a significant input of biologically active compounds in the diet.     

Food availability and nutrition in a seasonal perspective: A study from the Rukwa region in Tanzania

Most of the studies on seasonality in food supply and nutritional status have been carried out in areas characterized by extreme climatic conditions. This study was conducted in an area where the climate is favorable for grain cultivation. However, a large part of the population was found to face seasonal variations in food availability, most critically three to four months before the main harvest. Women lost about 3 percent of their weight in this period compared to the post harvest period. The nutritional status of preschool children declined in the lower socioeconomic group. These changes also coincided with a period of hard agricultural work, especially for women. The paper deals with factors affecting the duration of the maize stocks as well as strategies used when maize stocks are exhausted.     

Balancing food production and nature conservation in the Neotropical dry forests of northern Argentina

The growing human population and the increase in per capita food consumption are driving agriculture expansion and affecting natural ecosystems around the world. To balance increasing agriculture production and nature conservation, we must assess the efficiency of land‐use strategies. Soybean production, mainly exported to China and Europe, has become the major driver of deforestation in dry forest/savanna ecosystems of South America. In this article we compared land cover patterns (based on satellite imagery) and land‐use and human population trends (based on government statistics) in regions with two contrasting development pathways in the Chaco dry forests of northern Argentina, since the early 1970s. The area (ca. 13 million hectares) includes one of the largest continuous patches of tropical dry forests and has experienced rapid land‐use change. In the region where land use has been driven by government‐sponsored colonization programs, the expansion of extensive grazing has led to a growing rural population, low food production, and widespread environmental degradation. In contrast, in the region dominated by market‐driven soybean expansion, the rural population has decreased, food production is between 300% and 800% greater, and low‐density extensive cattle production has declined over extensive remaining forested areas, resulting in a land‐use trend that appears to better balance food production and nature conservation.     

The Paleoparasitology in Brazil and Findings in Human Remains from South America: A Review

The review article presents some of the history of how paleoparasitology started in Brazil, making highlight the great responsible Dr. Luiz Fernando Ferreira and Dr. Adauto Araújo, the trajectory of paleoparasitology in Brazil since 1978 and its performance in science to the present day. In sequence, it is made a presentation of parasitological findings on human remains found in archaeological sites in South America, highlighting Brazil, Argentina, Chile, and Peru, where major discoveries have occurred. Many of the parasites found in archaeological material and mentioned in this review went out of Africa with the peopling of Europe and from there they dispersed around the world, where climatic conditions allow the transmission. However, humans have acquired other parasites of animals, since humans invaded new habitats or creating new habits adopting new technologies, thus expanding its range of influence on the environment. Thus, this review article is finalized with information that explain the importance of these findings in the interaction between parasites, human host, and ambient.     

Gathered food plants in the mountains of Castilla-La Mancha (Spain): Ethnobotany and multivariate analysis

Gathered food plants (GFPs) (wild and weeds) are crucial for understanding traditional Mediterranean diets. Combining open interviews and free-listing questionnaires, we identified 215 GFP items, i.e., 53 fungi and 162 from 154 vascular plant species. The variation in frequency and in salience among the items follows a rectangular hyperbola. Highly salient species were Silene vulgaris (Moench) Garcke, Scolymus hispanicus L., and Pleurotus eryngii (DC.: Fr.) Quélet. Salience and frequency showed no correlation with the expected health benefits of each species. Regional frequency in the Mediterranean and local frequency are directly related. Thus, local food plants are much less “local” than expected. Different types of culinary preparations provide the most information in the cluster analysis of variables. The cluster analysis of items produced a tree with 10 clusters that form culture-specific logical entities, allowing people to structure their environment. Within each cluster, plant species are replaced and incorporated provided they resemble the general profile. This allows innovation and adaptation on a local level and explains the differences between adjacent localities in the list of species. Two types of clusters or species complexes are described: “species-labeled” and “uses-labeled.” Lastly, we discuss the underlying empirical basis of the ethnoclassification in the Mediterranean area.     

L-asparaginase production by isolated Staphylococcus sp. - 6A: design of experiment considering interaction effect for process parameter optimization

AIMS: Evaluation of fermentation process parameter interactions for the production of l-asparaginase by isolated Staphylococcus sp. - 6A. METHODS AND RESULTS: Fractional factorial design of experimentation (L18 orthogonal array of Taguchi methodology) was adopted to optimize nutritional (carbon and nitrogen sources), physiological (incubation temperature, medium pH, aeration and agitation) and microbial (inoculum level) fermentation factors. The experimental results and software predicted enzyme production values were comparable. CONCLUSION: Incubation temperature, inoculum level and medium pH, among all fermentation factors, were major influential parameters at their individual level, and contributed to more than 60% of total l-asparaginase production. Interaction data of selected fermentation parameters could be classified as least and most significant at individual and interactive levels. Aeration and agitation were most significant at interactive level, but least significant at individual level, and showed maximum severity index and vice versa at enzyme production. SIGNIFICANCE AND IMPACT OF THE STUDY: All selected factors showed impact on l-asparaginase enzyme production by this isolated microbial strain either at the individual or interactive level. Incubation temperature, inoculum concentration, pH of the medium and nutritional source (glucose and ammonium chloride) had impact at individual level, while aeration, agitation and incubation time showed influence at interactive level. Significant improvement (ninefold increase) in enzyme production by this microbial isolate was noted under optimized environment.     

Bipolar distributions in vascular plants: A review

Bipolar disjunct distributions are a fascinating biogeographic pattern exhibited by about 30 vascular plants, whose populations reach very high latitudes in the northern and southern hemispheres. In this review, we first propose a new framework for the definition of bipolar disjunctions and then reformulate a list of guiding principles to consider how to study bipolar species. Vicariance and convergent evolution hypotheses have been argued to explain the origin of this fragmented distribution pattern, but we show here that they can be rejected for all bipolar species, except for Carex microglochin. Instead, human introduction and dispersal (either direct or by mountain‐hopping)—facilitated by standard and nonstandard vectors—are the most likely explanations for the origin of bipolar plant disjunctions. Successful establishment after dispersal is key for colonization of the disjunct areas and appear to be related to both intrinsic (e.g., self‐compatibility) and extrinsic (mutualistic and antagonistic interactions) characteristics. Most studies on plant bipolar disjunctions have been conducted in Carex (Cyperaceae), the genus of vascular plants with the largest number of bipolar species. We found a predominant north‐to‐south direction of dispersal, with an estimated time of diversification in agreement with major cooling events during the Pliocene and Pleistocene. Bipolar Carex species do not seem to depend on specialized traits for long‐distance dispersal and could have dispersed through one or multiple stochastic events, with birds as the most likely dispersal vector.     

A new approach to define optimized range of medium composition for enhancement of hairy root production in fed-batch process

This work proposes a new methodology to identify the best medium concentrations for fed-batch production of hairy root using Datura innoxia as a model. Firstly, the role of each component on the growth rate is investigated separately. Then, an experimental design allows refining the optimization studying the interactions between the major species. The result analysis let to define concentration range optimized for fed-batch process. The work novelties lie in two aspects. Firstly, concentrations have been kept constant during each run. Thus, biomass uptakes do not affect the optimization and the growth rate is maintained constant during the exponential phase. Secondly, the effects of salts are generally studied. In this work, the influences of each ion are investigated in order to avoid bias due to the counter-ion effects. Compared to the classical B₅ medium, the optimized medium shows a significant improvement leading to more than 80% increase of final biomass production.     

Medium optimization by combination of response surface methodology and desirability function: an application in glutamine production

An optimization strategy based on desirability function approach (DFA) together with response surface methodology (RSM) has been used to optimize production medium in L-glutamine fermentation. Fermentation problems often force to reach a compromise between different experimental variables in order to achieve the most suitable strategy applying in industrial production. The importance of the use of multi-objective optimization methods lies in the ability to cope with this kind of problems. A sequential RSM with different combinations of glucose and (NH₄)₂SO₄ was performed to attain the optimal medium (OM-1) in glutamine production. Based on the result of RSM and the evaluation of production cost, a more economical optimal medium (OM-2) was obtained with the aid of DFA. In DFA study, glutamate, the main by-product in glutamine fermentation as another response was considered. Compared with OM-1 in validated experiment, similar amounts of glutamine were obtained in OM-2 while the concentration of glutamate and the production cost decreased by 53.6 and 7.1%, respectively.     

Immunoaffinity column clean-up techniques in food analysis: A review

This review provides a critical assessment of the applications of immunoaffinity columns for sample clean-up in the field of food safety. The performance of immunoaffinity columns are compared in terms of specificity, binding capacity and recovery, and commercial disposable columns are contrasted with home-made columns. Areas covered include multiple-use of columns, multiple-analyte columns, use with automated systems and validation of IAC methods. Publications illustrating the many varied applications of IAC for sample clean-up in the areas of mycotoxins, veterinary drug residues, pesticide residues, environmental contaminants and vitamins have been compiled, comparing extraction methods, achievable recovery, and illustrating the variety of end-detection methods that have been employed.     

Ethnobotanical Knowledge and Crop Diversity in Swidden Fields: A Study in a Native Amazonian Society

Crop diversity protects food consumption in poor households within developing nations. Here we estimate the association between crop diversity on swidden fields and ethnobotanical knowledge. We conducted research among 215 male household heads from a native Amazonian society. Using multivariate regressions, we found higher crop diversity among households that depend on agricultural production for household consumption. We also found a statistically significant and positive, but low, association between the ethnobotanical knowledge of the male household head and crop diversity. Doubling the stock of ethnobotanical knowledge of the male household head is associated with a 9% increase in the number of crops sown by a household. The association remained after we controlled for the household level of market exposure, but vanished after we controlled for the social capital of the male household head. Future research should compare the association between ethnobotanical knowledge and crop diversity across different agricultural systems (i.e., home gardens, fallow fields).     

Long-term dynamics of water and carbon in semi-arid ecosystems: a gradient analysis in the Patagonian steppe

We used a soil water simulation model and remotely sensed data to study the long-term dynamics of transpiration, evaporation, drainage and net primary production across a precipitation gradient in Northwestern Patagonia (Argentina). The proportion of precipitation transpired, the precipitation use efficiency and the transpiration use efficiency were constant across the gradient that covered a range of 150 to 600 mm. The proportion of water evaporated was higher than the proportion drained at the driest extreme of the gradient. The opposite relationship was observed at the wet extreme.Two important characteristics of arid-semiarid systems dominated by winter precipitation emerged from our analyses: the importance of drainage losses and the asynchrony between evaporation and transpiration fluxes. These characteristics of the water dynamics influence the relative abundance of plant functional types and are crucial to generate heterogeneity at the landscape level. The coefficient of variation (CV) of transpiration, evaporation and ANPP was, in general, lower than the CV of annual precipitation. This pattern suggests a buffering capacity of the ecosystem. The ecosystem would be able to damp at the functional level inter-annual changes in the availability of resources.