Protein,amino acid and mineral composition of some edible insects from Thailand

This paper focuses on the nutritional profiles of four edible insects from Thailand: the Bombay locust, scarab beetle, house cricket, and mulberry silkworm.The insects were ‘high’ in protein ranging from 27 g to 54 g/100 g edible portion in fresh weight basis, however, only the silkworm met the FAO/WHO requirements of 40% essential amino acids and 0.6 ratio of essential to non-essential amino acids. Tryptophan is the limiting amino acid in the locust and cricket, lysine in the scarab beetle, and leucine in the silkworm.The locust is a ‘source’ of iron and is ‘high’ in zinc, while the scarab beetle is a ‘source’ of magnesium and is ‘high’ in iron and zinc. The cricket bought from the street is a ‘source’ of iron and magnesium and is ‘high’ in zinc, while the cricket from the supermarket is a ‘source’ of calcium (the only one among the insect samples) and is ‘high’ in iron, magnesium and zinc. And lastly, the silkworm, regardless of where it was purchased, is a ‘source’ of iron and is ‘high’ in magnesium and zinc. The arsenic, cadmium, lead and mercury content of all the insect samples were well below the maximum values and are deemed safe for consumption as either feed material or complete feed.Edible insects can contribute to people's nutrient requirements and should be sustainably utilized. Aside from direct consumption, there is a huge potential for using the insects as raw material and fortificant in food processing.     

Isolation of Native Soil Microorganisms with Potential for Breaking Down Biodegradable Plastic Mulch Films Used in Agriculture

Fungi native to agricultural soils that colonized commercially available biodegradable mulch (BDM) films were isolated and assessed for potential to degrade plastics. Typically, when formulations of plastics are known and a source of the feedstock is available, powdered plastic can be suspended in agar-based media and degradation determined by visualization of clearing zones. However, this approach poorly mimics in situ degradation of BDMs. First, BDMs are not dispersed as small particles throughout the soil matrix. Secondly, BDMs are not sold commercially as pure polymers, but rather as films containing additives (e.g. fillers, plasticizers and dyes) that may affect microbial growth. The procedures described herein were used for isolates acquired from soil-buried mulch films. Fungal isolates acquired from excavated BDMs were tested individually for growth on pieces of new, disinfested BDMs laid atop defined medium containing no carbon source except agar. Isolates that grew on BDMs were further tested in liquid medium where BDMs were the sole added carbon source. After approximately ten weeks, fungal colonization and BDM degradation were assessed by scanning electron microscopy. Isolates were identified via analysis of ribosomal RNA gene sequences. This report describes methods for fungal isolation, but bacteria also were isolated using these methods by substituting media appropriate for bacteria. Our methodology should prove useful for studies investigating breakdown of intact plastic films or products for which plastic feedstocks are either unknown or not available. However our approach does not provide a quantitative method for comparing rates of BDM degradation.     

Juvenile versus adult competition

A general class of age-structured models based upon the McKendrick/von Foerster equations are used to study intraspecific competition between juveniles and adults. Criteria for the existence and stability of equilibria are obtained and the dependence of equilibrium stability (i.e. equilibrium resilience) on competition coefficients is analyzed for low inherent net reproductive numbers. The results are applied to the question of whether juvenile vs. adult intraspecific competition is stabilizing or destabilizing. Two types of competition are studied. The first, involving suppressed adult fertility due to competition from juveniles, was found to be destabilizing in that equilibrium levels are lowered and equilibrium resilience weakened by increased competition. The second, involving increased juvenile mortality due to competition from adults, was found to be considerably more complicated. While equilibrium levels were again reduced by increased competition, equilibrium resilience can either be weakened or strengthened. A criterion for determining the effects on resilience is derived and several examples are given to illustrate various possibilities in this case.The author gratefully acknowledges the support of the Applied Mathematics Division and the Population Biology/Ecology Division of the National Science Foundation under NSF grant No. DMS-8902508Research supported by the Department of Energy under contracts W-7405-ENG-36 and KC-07-01-01     

A keratin of fetal skin is reexpressed in human keratinocytes transformed by SV40 virus or treated with the tumor promoter TPA

SV40-transformation as well as treatment with tumor promoters produce alterations in morphology, differentiation and keratinization of human keratinocytes. Two cell lines of SV40-transformed keratinocytes and primary cultures of keratinocytes treated with the tumor promoter 12-O-tetradecanoyl phorbol-13-acetate (TPA) were found to contain an additional protein of 52.5 kD molecular weight (MW). This protein was identified by its reactivity with the monoclonal antibody TROMA-I as being keratin no. 8, a keratin normally present only in simple epithelia. Since this keratin is present in fetal epidermis but disappears gradually when fetal skin becomes multilayered after week 13 of development (Moll et al., Differentiation 23 (1982) 170. [23]), it suggests that SV40 virus and TPA are able to induce in human keratinocytes the reexpression of fetal characters.     

Biotin interference in immunoassays based on biotin-strept(avidin) chemistry: An emerging threat

Biotinylated antibodies/antigens are currently used in many immunoassay formats in clinical settings for diversified analytes and biomarkers to offer high detection selectivity and sensitivity. Biotin cannot be synthesized by mammals and must be taken as an essential supplement. Normal intake of biotin from various foods and milk causes no effect on the streptavidin/biotin-based immunoassays. However, overconsumption of biotin (daily doses 100–300 mg) poses a significant problem for immunoassays using the biotin-strept(avidin) pair. Biotin interferences are noted in immunoassays of thyroid markers, drugs, hormones, cancer markers, the biomarker for cardiac function (β–human chorionic gonadotropin), etc. The biotin level required for serious interference in test results varies significantly from test to test and cannot easily be predicted. Immunoassay manufacturers with technologies based on strept(avidin)-biotin binding must investigate the interference from biotin (up to at least 1200 ng/mL or 4.9 μM of biotin) in various formats. There is no concrete solution to circumvent the biotin interference encountered in blood samples, short of biotin removal. Considering the short half-life of biotin in the human body, patients must stop taking biotin supplements for >48 h before the test. However, this scenario is not considered for patients in emergency situations or those with biotinidase deficiency, mitochondrial metabolic disorders or multiple sclerosis. Apparently, a rapid analytical procedure for biotin is urgently needed to quantify for its interference in immunoassays using strep(avidin)-biotin chemistry. To date, there is no quick and reliable procedure for the detection of biotin at below nanomolar levels in blood and biological samples.Traditional lab-based techniques including HPLC/MS-MS cannot process an enormous number of public samples. Biosensors with high detection sensitivity, miniaturization, low cost, and multiplexing have the potential to address this issue.     

Carbon footprint of science: More than flying

Previous efforts to evaluate the climate change impact of researchers have focused mainly on transport related impact of conference attendance, and infrastructure. Because these represent only a part of the activities involved in the science making process this short note presents the carbon footprint of a complete science making process of one specific case. Apart from presenting the total footprint, we evaluate the relative contribution of the different scientific activities, and quantify mitigating possibilities. The case PhD project had a carbon footprint of 21.5 t CO₂-eq (2.69 t CO₂-eq per peer-reviewed paper, 0.3 t CO₂-eq per citation and 5.4 t CO₂-eq per h-index unit at graduation) of which general mobility represents 75%. Conference attendance was responsible for 35% of the carbon footprint, whereas infrastructure related emissions showed to contribute 20% of the total impact. Videoconferencing could have reduced the climate change impact on this case PhD with up to 44%. Other emission reduction initiatives, such as using green electricity, reduction of energy consumption, and promoting commuting by bicycle, could have triggered a reduction of 14% in this case study. This note fits in the movement of academics and universities willing to be green. The study confirms that researchers’ mobility is the biggest contributor to his or her carbon footprint, but is not limited to conference attendance, showing the importance of considering all activities in the science making process.     

Recognising bias in Common Era temperature reconstructions

A steep decline in the quality and quantity of available climate proxy records before medieval times challenges any comparison of reconstructed temperature and hydroclimate trends and extremes between the first and second half of the Common Era. Understanding of the physical causes, ecological responses and societal consequences of past climatic changes, however, demands highly-resolved, spatially-explicit, seasonally-defined and absolutely-dated archives over the entire period in question. Continuous efforts to improve existing proxy records and reconstruction methods and to develop new ones, as well as clear communication of all uncertainties (within and beyond academia) must be central tasks for the paleoclimate community.     

L’espèce entre résilience et sérendipité

This paper is a personal reflection rather than a demonstration. It discusses the relationship between two properties of species: resilience, which allows species to resist perturbations, and serendipity, which allows them to change even under weak perturbations. Among the great problems raised by the transformation of species, the most astonishing fact is that species are extraordinarily stable. This stability, to which we hardly pay attention, is part of our everyday life, up to the point that it forms the basis of our deepest thought, the eternal Ideas of Plato and the substance of Aristotle. This suspected stability has also been used to support doctrines of the loathed creationists. All the definitions of species, even the arbitrary boundaries and nominalist conventions, bear the embarrassing sign of resilience, which contradicts the idea of evolution.     

National Science Foundation support of physical anthropology research

Awards by the National Science Foundation Anthropology Program are analyzed and patterns of overall NSF support, proposal submissions, and success rates discerned. An attempt is made to explain these.