A generalized approach for the calculation and automation of potentiometric titrations Part 2. Redox Titrations

The very fast calculation procedure described earlier is applied to calculate the titration curves of complicated redox systems. The theory is extended slightly to cover inhomogeneous redox systems. Titrations of iodine or 2,6-dichloroindophenol with ascorbic acid are described. It is shown that correspondence between theory and practice is good as long as the relevant stability constants and redox potentials are known with sufficient accuracy

Developing agricultural solutions with smallholder farmers - How to get started with participatory approaches

Farm Management,

Forage Legumes for supplementing village pigs in Lao PDR

The Lao government has placed highest priority in its rural development strategy to improving livestock production systems, given the potential of livestock production to alleviate poverty and reduce shifting cultivation. Pig rearing is a common smallholder livelihood activity in northern Laos with almost all farm households raising a few pigs. Pigs are sold to cover household expenses such as school fees and medications, and they are an asset that can be liquidated to cover expenses in emergencies. Pig production is almost invariably the domain of women, who spend 2-3 hours each day to collect and prepare feed for pigs. Recent surveys identified poorly balanced pig diets in northern Laos, particularly highlighting very low protein content, as a major contributor to the observed poor growth rates and poor reproductive performance of pigs in northern Laos, and showed that farmers who had started to supplement traditional pig diets with the forage legume Stylosanthes guianensis (Stylo) were experiencing increased animal growth rates and reduced labour requirements for feeding

The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard

The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from the cowsheds. Both the greenhouse and the cowsheds are now derelict. This site represents an unusually nutrient-rich location with considerable development of organic soils, in stark contrast to the naturally forming organic soils in Svalbard, which are typically thin and nutrient poor. Few previous studies have examined the soil invertebrate communities of human-disturbed or -created habitats in the Arctic. In an often nutrient-poor terrestrial environment, it is unclear how the invertebrate fauna will react to such nutrient enhancement. In these soils, 46 species of invertebrates were determined. Eleven species have not been recorded from other habitats in Svalbard and are hence likely to have been introduced. The native species assemblage in the anthropogenic soils was not atypical for many natural sites in Svalbard. Despite the enriched organic soils and highly ameliorated winter temperature conditions, the soil invertebrate fauna biodiversity does not appear to be enhanced beyond the presence of certain probably introduced species

Description of the Alpine Micropsectra oberaarensis sp. n. with taxonomic comments on the attenuata group (Diptera: Chironomidae)

Ahitherto unknown species in the Micropsectra attenuata group, Micropsectra oberaarensis sp. n., has recently been collected from high elevation in the Berner Alps (Switzerland).The male and pupa of the new species, and the previously unknown larva of the closely related Micropsectra seguyi Casas & Laville, are here described and diagnosed. These two species, Micropsectra attenuata Reiss and Micropsectra auvergnensis Reiss are morphologically similar as adult males, but can easily be separated in their pupal life stage. Partial COI gene sequences indicate sufficient interspecific variation to separate the morphologically two most similar species, M. oberaarensis and M. seguyi. Micropsectra davigra Gilka & Abramczuk is presented as a new junior synonymto M. pharetrophora Fittkau& Reiss and a key to males of all eight West Palaearctic species in the attenuata group is given. The diagnostic characters separating the genera Parapsectra and Krenopsectra from the attenuata group are briefly discussed

New findings and an overall assessment of Norwegian biting midges (Diptera, Ceratopogonidae)

Source at: http://www.entomologi.no/journals/nje/2022-1/pdf/nje-vol69-no1-2022-82-190-dominiak.pdfFaunistic studies on biting midges conducted mostly in South Norway between 2006 and 2020, as well as a revision of available literature, resulted in a new comprehensive checklist of the species known from mainland Norway. In total, 21 genera and 216 species of Ceratopogonidae have been registered, of which as many as 165 are with Linnaean names. For the remaining 51 species interim names are given as no existing nominal species could be assigned. Four genera, namely Ceratoculicoides Wirth & Ratanaworabhan, 1971, Monohelea Kieffer, 1917b, Phaenobezzia Haeselbarth, 1965 and Probezzia Kieffer, 1906, and 58 species are reported from Norway for the first time. Records of nine biting midge species previously mentioned from the country turned out to be uncertain and are currently treated as doubtful. In Norway, the most species-rich genera of Ceratopogonidae are: Culicoides Latreille, 1809 with 34, Forcipomyia Meigen, 1818 with 29, Dasyhelea Kieffer, 1911a with 22, Atrichopogon Kieffer, 1906 with 16, Bezzia Kieffer, 1899 with 15, and Palpomyia Meigen, 1818 with 15 reported species

DNA barcoding for species identification of insect skins: A test on Chironomidae (Diptera) pupal exuviae

Chironomidae (Diptera) pupal exuviae samples are commonly used for biological monitoring of aquatic habitats. DNA barcoding has proved useful for species identification of chironomid life stages containing cellular tissue, but the barcoding success of chironomid pupal exuviae is unknown. We assessed whether standard DNA barcoding could be efficiently used for species identification of chironomid pupal exuviae when compared with morphological techniques and if there were differences in performance between temperate and tropical ecosystems, subfamilies, and tribes. PCR, sequence, and identification success differed significantly between geographic regions and taxonomic groups. For Norway, 27 out of 190 (14.2%) of pupal exuviae resulted in high-quality chironomid sequences that match species. For Costa Rica, 69 out of 190 (36.3%) Costa Rican pupal exuviae resulted in high-quality sequences, but none matched known species. Standard DNA barcoding of chironomid pupal exuviae had limited success in species identification of unknown specimens due to contaminations and lack of matching references in available barcode libraries, especially from Costa Rica. Therefore, we recommend future biodiversity studies that focus their efforts on understudied regions, to simultaneously use morphological and molecular identification techniques to identify all life stages of chironomids and populate the barcode reference library with identified sequences.publishedVersion© The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited

Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration.

BACKGROUND: It has been proposed that antioxidants may prevent cellular damage in the retina by reacting with free radicals that are produced in the process of light absorption. OBJECTIVES: The objective of this review was to assess the effects of antioxidant vitamin or mineral supplementation, or both, on the progression of age-related macular degeneration (AMD). SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2005, Issue 4); MEDLINE (1966 to January 2006); SIGLE (1980 to March 2005); EMBASE (1980 to January 2005); NRR (2005, Issue 4); AMED (1985 to January 2006); and PubMed (24 January 2006 covering last 60 days), reference lists of identified reports and the Science Citation Index. We contacted investigators and experts in the field for details of unpublished studies. SELECTION CRITERIA: We included randomised trials comparing antioxidant vitamin or mineral supplemention (alone or in combination) to a control intervention in people with AMD. DATA COLLECTION AND ANALYSIS: The author extracted data and assessed trial quality. Where appropriate, data were pooled using a random-effects model unless three or fewer trials were available in which case a fixed-effects model was used. MAIN RESULTS: Eight trials were included in this review. The majority of people were randomised in one trial (AREDS in the USA) that found a beneficial effect of antioxidant (beta-carotene, vitamin C and vitamin E) and zinc supplementation on progression to advanced AMD (adjusted odds ratio 0.68, 99% confidence interval 0.49 to 0.93). People taking supplements were less likely to lose 15 or more letters of visual acuity (adjusted odds ratio 0.77, 99% confidence interval 0.58 to 1.03). Hospitalisation for genito-urinary problems was more common in people taking zinc and yellowing of skin was more common in people taking antioxidants. The other trials were, in general, small and the results were inconsistent. AUTHORS' CONCLUSIONS: The evidence as to the effectiveness of antioxidant vitamin and mineral supplementation in halting the progression of AMD comes mainly from one large trial in the USA. The generalisability of these findings to other populations with different nutritional status is not known. Further large, well-conducted randomised controlled trials in other populations are required. Long-term harm from supplementation cannot be ruled out. Beta-carotene has been found to increase the risk of lung cancer in smokers; vitamin E has been associated with an increased risk of heart failure in people with vascular disease or diabetes

A faunistic study of water mites (Hydrachnidia and Halacaridae) from southern Norway

Targeted sampling of a broad range of freshwater habitats over the past five years, combined with screening of recent records available in online databases, substantially increased the number of water mite species known to Norway. Among the 190 species now recorded (187 Hydrachnidia and 3 Halacaridae), 47 are new to Norway, while 21 are recorded from Fennoscandia for the first time. Partial COI-sequences (DNA barcodes) of 110 species were generated in our project, and comparative analyses showed indications of cryptic species diversity for ten species. We provide an updated checklist for the Norwegian water mite fauna with comments on distribution and ecology. Included are detailed locality records, ecological habitat characteristics and some important physicochemical parameters for the collecting sites visited by us. For species of particular interest, open taxonomic questions and needs for further research are discussed.submittedVersio

Development of Forage Components Through Farmer Participatory Research

This paper describes farmer participatory research activities aimed at developing appropriate forage technologies with smallholders in Southeast Asia. Farmers are actively involved from the early stages, working as equal partners with researchers. This has led to a better understanding of selected farming systems, identification of technologies that have potential for testing by farmers, and better understanding of the criteria farmers consider important for forages to be useful within those farming systems