Icacina oliviformis (Icacinaceae): A close look at an underexploited food plant. III. Ecology and production

Data are presented on the ecology and production ofIcacina oliviformis (Poiret) Raynal in natural stands in northern Central African Republic. The species grows on a variety of soils and in numerous plant communities. It is fire adapted, and thrives when burned in the early dry season. The plant is primarily bee pollinated and has a number of pests that infest the stems and young fruits. Plant densities are high, with a maximum of ca. 5345 plants/ha in the study sites. Standing tuberous root biomass can be considerable, with a maximum of ca. 19904 kg/ha for the study sites. Seed yield in the sample sites was relatively low with a maximum of ca. 214 kg/ha. With proper management, yields of both seed and tuberous roots could be substantially increased.     

Icacina oliviformis (Icacinaceae): A close look at an underexploited crop. I. Overview and ethnobotany

Icacina oliviformis is an underexploited, suffrutescent, savannah pyrophyte used for its edible seeds, tuberous roots, and fruit mesocarp in many areas of west and north-central Africa. The large seeds provide a relied-upon resource in Senegal, Guinea-Bissau, and the Central African Republic at the end of the dry season when food reserves in the villages are at their lowest annual levels. The tuberous roots, sometimes weighing over 50 kg, provide a rich source of starch in times of famine. This species deserves consideration for use in extensive agroforestry schemes in savannah habitats of west-central Africa.     

Stefan Westermann: a close look at kinetochore function. Interviewed by Caitlan Sedwick

Stefan Westermann is probing the structure and function of the yeast kinetochore.     

A close look at late carboniferous algal mounds: Schulterkofel,Carnic Alps,Austria

Summary During the uppermost Carboniferous and lowermost Permian algal mounds were formed in inner shelf settings of the Carnic Alps (Austria/Italy). A specific mound type, characterized by the dominance of the dasyclad green alga Anthracoporella was studied in detail with regard to geometry, relationship between mound and intermound rocks, composition of the sediment, biota and diagenetic criteria. The two meter-sized mounds studied, occur within depositional sequences of transgressive systems tracts in the Lower Pseudoschwagerina Limestones (uppermost Gzhelian) at the flank of the Schulterkofel. The mounds consist of an Anthracoporella core facies with a spongecrust boundstone facies at the base and at the top. The massive limestones of the Anthracoporella core facies exhibit abundant algal tufts and bushes, frequently in life position. The limestones of the intermound facies represented by thin-bedded bioclastic wackestones and packstones with abundant phylloid algae underlie and overlie the mounds. Intercalations of intermound beds within the mound facies indicate sporadic disruption of mound growth. Onlapping of intermound beds on steep mound flanks indicate rapid stabilization and lithification of mound flanks and the existence of a positive paleorelief. Asymmetrical shape of the mounds may be current controlled. Mound and intermound biota differ in the prevailing algae but are relatively similar with regard to associated foraminifera. Conspicuous differences concern bioerosion and biogenic encrustations. Bothare, high in intermound areas but low in the Anthracoporella core facies. The mounds show no ecological zonation. The mounds grew by in-place accumulation of disintegrated algal material and trapped bioclastic material between erect algal thalli. The comparison of the various Anthracoporella mounds demonstrates that almost each mound had ist own history. Establishing a general model for these mounds is a hazardous venture.     

A closer look at intraspecific variation of Cerataphis brasiliensis (Hempel) (Hemiptera: Hormaphididae)

The aim of our study was to characterize Cerataphis brasiliensis Hempel, an aphid of native palm tree of tropical savannas (cerrado), and to record intraspecific variation. We found two parthenogenetic forms of apterous viviparae females of C. brasiliensis. We differentiate the two forms through measurable and qualitative characters: (i) length of cephalic horns, (ii) number of antennal segments, (iii) presence or absence of wax glands, (iv) location of siphunculi.     

A new look at xylanases: an overview of purification strategies

Interest in xylanases from different sources has increased markedly in the past decade, in part because of the application of these enzymes in the pulp and paper industry. Purity and purification costs are becoming important issues in modern biotechnology as the industry matures and competitive products reach the marketplace. Thus, new paths for successful and efficient xylanase recovery have to be followed. This article reviews the isolation and purification methods used for the recovery of microbial xylanases. Origins and applications of xylanases are described, highlighting the special features of this class of enzymes, such as the carbohydrate-binding domains (CBDs) and their importance in the development of affinity methodologies to increase and facilitate xylanase purification. Implications of recombinant DNA technology for the isolation and purification of xylanases are evaluated. Several purification procedures are analyzed, taking into consideration the sequence of the methods used in each and the number of times each method is used. New directions to improve xylanase separation and purification from fermentation media are described.     

Succession of pelagic marine bacteria during enrichment: a close look at cultivation-induced shifts

Enrichment experiments with North Sea bacterioplankton were performed to test if rapid incubation-induced changes in community structure explain the frequent isolation of members of a few particular bacterial lineages or if readily culturable bacteria are common in the plankton but in a state of dormancy. A metabolic inhibitor of cell division (nalidixic acid [NA]) was added to substrate-amended (S+) and unamended (S-) grazer-free seawater samples, and shifts in community composition and per cell DNA and protein content were compared with untreated controls. In addition, starvation survival experiments were performed on selected isolates. Incubations resulted in rapid community shifts towards typical culturable genera rather than in the activation of either dormant cells or the original DNA-rich bacterial fraction. Vibrio spp. and members of the Alteromonas/Colwellia cluster (A/C) were selectively enriched in S+ and S-, respectively, and this trend was even magnified by the addition of NA. These increases corresponded with the rise of cell populations with distinctively different but generally higher protein and DNA content in the various treatments. Uncultured dominant gamma-proteobacteria affiliating with the SAR86 cluster and members of the culturable genus Oceanospirillum were not enriched or activated, but there was no indication of substrate-induced cell death, either. Strains of Vibrio and A/C maintained high ribosome levels in pure cultures during extended periods of starvation, whereas Oceanospirillum spp. did not. The life strategy of rapidly enriched culturable gamma-proteobacteria could thus be described as a "feast and famine" existence involving different activation levels of substrate concentration.     

Characterization of biotechnological processes and products using high-performance liquid chromatography (HPLC). II. Analyses of potato starch hydrolysis products

Potato starch hydrolysis products were analyzed for glucose, maltose, higher oligomeric carbohydrates (to a degree of polymerization, dp 11) and 5-hydroxymethylfurfural (HMF) using high-performance liquid chromatography. For quick qualitative and quantitative analyses short glass columns [12] of high efficiency were useful. The hydrolyses were carried out by means of enzymes (e.g. α- and β-amylase) or mineral acids. For the acid degradation procedures hydrochloric acid, sulfuric acid and phosphoric acid of different concentrations (0.1…2.0 N) during times ranging from 5 to 60 min at temperatures ranging from 100 to 140°C were used. Maximum glucose contents (163.4 g/l and 169.3 g/l) were found after 40 to 50 min of hydrolysis in 0.1 N hydrochloric acid heated to 120°C. These values are equivalent to 78.9% or 81.7% glucose yield referred to the initial potato starch amount, respectively. The calculated HMF concentrations were 140 and 180 mg/l.     

Dreams and revelations: A critical look at Kelsey.

After a seven-century lull in Christian scholarship about dreams, the mid-Twentieth Century saw the beginning of a growing effort to convince Christians dreams are a significant means of communication with God. This essay summarizes and criticizes Morton Kelsey's central argument concerning the Christian significance of dreams in his God, dreams, and revelation (1991). Kelsey's is a thoughtful version of the argument common to his colleagues. As such, it displays both the strengths and the weaknesses of the general position. It correctly reminds Christians of dreams' significance in their past. But if Kelsey means to offer a fully supported logical argument, that argument is not clear and even the most sympathetic restatement of it leaves it unsound. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proteomics at the interface of psychology, gut physiology and dysfunction: an underexploited approach that deserves expansion

Gut functions such as digestion and absorption are essential to life and the emerging insights into the gut-brain axis - that is, the cross talk between the enteric and CNS - point towards critical links between (eating) behavior, psychology, whole body and gut physiology, and digestive and overall health. While proteomics is ideally positioned to shed more light on these interactions, be it applied to the periphery (e.g., blood) or the locus of action (i.e., the gut), it is to date largely underexploited, mainly because of challenging sampling and tissue complexity. In view of the contrast between potential and current delivery of proteomics in the context of intestinal health, this article briefs the reader on the state-of-the-art of molecular intestinal research, reviews current proteomic studies (explicitly focusing on the most recent ones that target inflammatory bowel disease patient samples) and argues for an expansion of this research field.     

Proteomics at the interface of psychology,gut physiology and dysfunction: an underexploited approach that deserves expansion

Gut functions such as digestion and absorption are essential to life and the emerging insights into the gut–brain axis – that is, the cross talk between the enteric and CNS – point towards critical links between (eating) behavior, psychology, whole body and gut physiology, and digestive and overall health. While proteomics is ideally positioned to shed more light on these interactions, be it applied to the periphery (e.g., blood) or the locus of action (i.e., the gut), it is to date largely underexploited, mainly because of challenging sampling and tissue complexity. In view of the contrast between potential and current delivery of proteomics in the context of intestinal health, this article briefs the reader on the state-of-the-art of molecular intestinal research, reviews current proteomic studies (explicitly focusing on the most recent ones that target inflammatory bowel disease patient samples) and argues for an expansion of this research field.     

The food plant preferences of Phratora vitellinae (Coleoptera: Chrysomelidae)

In the Upper Rhine (Petite Camargue, Saint Louis, France) study site, Ph. vitellinae are found mainly on Salix nigricans on which they are bivoltine. Some beetles are occasionally observed on S. purpurea, especially in Spring, but never on S. alba, S. caprea and S. cinerea. In other European localities, S. nigricans or S. hegetschweileri at higher elevations are frequently recorded as host-plants. However, some populations are also found on S. purpurea, P. tremula and P. trichocarpa x deltoïdes, usually when neither S. nigricans nor S. hegetschweileri are present.All the Salicaceae on which Ph. vitellinae was observed in the field have leaves rich in phenylglycosides and with glabrous lower surfaces, at least in Spring. Ph. vitellinae was never recorded on those Salix species with leaf undersurfaces densely covered with trichomes.At the time of emergence of the beetles from hibernation, S. nigricans leaves are more developed than those of S. purpurea and S. cinerea. Moreover, those S. nigricans trees with the longer shoots in Spring support the largest number of beetles at their emergence. The preference of Ph. vitellinae for S. nigricans might be reinforced by these plenological differences.In the Petite Camargue, the same S. nigricans trees support the largest populations of beetles from one generation to the next and from year to year. This suggests that S. nigricans does not respond to defoliation with induced resistance to the beetles.All shoots on the branch seem to be equally suitable and attractive for oviposition. The older leaves at the base of the shoot and the younger ones at the top are less favored by ovipositing females. Survival of the egg batches and the groups of freshly emerged larvae is lower on the distal shoots of the branch and on the younger leaves. This might be due to a higher degree of exposure to predators.     

The food plant preferences of Phratora vitellinae (Coleoptera: Chrysomelinae)

The specialisation of the beetles from the Petite Camargue on Salix nigricans was confirmed by laboratory food-plant trials. When S. nigricans is not present in the choice offered, other Salix species are accepted and the following ranking, in decreasing order of preference, can be established: S. nigricans, S. purpurea, Populus nigra, P. tremula, S. alba, s. caprea and S. cinerea. S. nigricans leaves are the richest in salicin of the 4 most acceptable plant species. The 3 least acceptable species have the undersurface of their leaves covered with trichomes.The food-plant preferences of 2 populations from central Europe and 2 from Belgium differ both in the field and in the laboratory. The level of dietary specialisation also differs from population to population. The populations originating from localities (Oignie in Belgium and the Petite Camargue in central Europe) where their favorite food-plants in the field and in the laboratory (respectively P. tremula and S. nigricans) are abundant, show clearer preferences than the populations from localities (Grammont in Belgium and Herrliberg in central Europe) where these plants are scarcer or even absent, due to human influence.The Salicaceae tested, as seen by the more specialised beetles of Oignie and the Petite Camargue, include both a strongly preferred plant (P. tremula or S. nigricans) and two or three strongly disliked species (S. alba, S. caprea and S. cinerea). for these beetles, laboratory preferences and field observations of host plant species are in agreement. It is interesting that S. nigricans, although not present in Belgium, is the second most preferred food of the Belgian beetles in laboratory trials. Similarly, P. tremula, the preferred food of the Belgian beetles, is well accepted by the central European beetles.For the less specialised beetles of Grammont and Herrliberg, the same Salicaceae include strongly disliked speicies but no single strongly preferred species. In the Herrliberg population, with rather poorly defined preferences, preference for the favorite species of the more specific population from the same geographical area (Petite Camargue) can readily be produced in the laboratory by conditioning.     

Homeotic Sexual Translocations and the Origin of Maize (Zea Mays, Poaceae): A New look at an old problem

In the Origin of Maize Controversy, the Orthodox Teosinte Hypothesis (OTH; Beadle 1939, 1972; Iltis 1971), five key mutations change 2-ranked (distichous) ears of teosinte (wild Zea) with a single row of grains per rank to 4- to many-ranked (polystichous) maize ears with a double row of grains per rank. BUT teosinte ears are lateral to the 1° branch axes, maize ears, like their male homologues, the teosinte I° branch tassel spikes, terminal, an enigma long unrecognized, hence ignored. In the Catastrophic Sexual Transmutation Theory (CSTT; Iltis 1983b, 1987), now abandoned, the I° branch tassel (male) of teosinte (spikelets soft-glumed, paired, i.e., double-rowed per rank, as in maize ears), when brought under female hormonal control by branch condensation, becomes feminized into a maize proto-ear. BUT lateral ears should then have remained teosintoid (2-ranked, each rank with a single row of grains), yet are in fact double-rowed. Combining OTH and CSTT, the new Sexual Translocation Theory (STLT) is based on: first, the branching pattern of teosinte ear clusters (Cámara-H. & Gambino 1990), sequentially maturing, sympodially branching, typically Andropogonoid systems, called rhipidia (sing, rhipidium), where each higher order (younger) ear originates as a lateral branch of its lower order, earlier maturing predecessor; and second, on 3 or 4 key mutations [cupule reduction, softening of glumes, doubling of female spikelets], which, by projecting outward the grains, invited human domestication by making them accessible. Within each ear cluster, the earliest maturing, hence nutrient-monopolizing and largest ear would be selected, all younger ears, already nutrientinhibited, suppressed. As fewer, larger ears evolved, and branch internode condensation moved male tassels into female hormonal zones, homeotic conversions translocated female morphology to terminal male positions: first replacing each of the II° branch tassels, and ultimately the 1° branch tassel (male), with an ear (female). With this, now female structure in the apically dominant, hence most nutrient-demanding terminal position gradually suppressing all subsidiary ears on the 1° branch beneath it, mutations for polystichy (contingent on nutrient overload) were finally allowed to become expressed, and the multi-rowed maize ear (at first with an atavistic male tail) evolved. Favored by human selection, these increases in apical dominance by stepwise homeotic sexual conversions explain both archeological and morphological realities, but need to be harmonized with recent results of developmental genetics. Current evidence suggests that teosinte was first tended for its green ears and sugary pith by hunter-gatherers as an occasional rainy-season food in small “garden” populations away from its homeland, and not for its abundant grain-containing, hard fruitcases, which easily mass-collected but useless as food, are as yet unknown from the archeological record. A rare grain-liberating teosinte mutation (probably expressed in only one “founder” plant, a mazoid “Eve”), which exposed the encased grain for easy harvest, was soon recognized as useful, collected and planted (or self-planted). Thus maize was started on its way to a unique horticultural domestication that is not comparable to that of the temperate Old World mass-selected agricultural grains.