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,

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

Psyllid Resistance in the Leucaena Genus

Leucaena species varied from highly susceptible to highly resistant in their response to the psyllid insect (Heteropsylla cubana) at 2 sites, a high psyllid environment at Brisbane, Australia and a moderate psyllid environment at Los Baños, Philippines. L. leucocephala was the most susceptible species. There was considerable intraspecific variation in psyllid resistance within L. collinsii, L. diversifolia and L. pallida. Plant reponse to psyllid challenge between environments was highly correlated but not linear. The higher psyllid challenge environment at Brisbane permitted greater discrimination between species and fewer Leucaena species were ranked as psyllid resistant

Sheep and Forage Productivity in Rubber Plantations

The concept of integration of sheep with rubber plantations for weed control and meal production is rapidly gaining recognition in Malaysia. A series of experiments were set up with ACIAR support to determine the level of forage and animal production achievable in rubber plantations and to introduce and evaluate new forage germplasm for sheep grazing under rubber. These experiments showed that (i) the productivity of the currently used cover crops and naturally occurring further as rubber trees matured, (ii) the proportion of the unpalatable cover crop Caloponuim caeruleum increased rapidly with sheep grazing in immature rubber, (iii) reasonable sheep live-weight gains could be sustain mature rubber only at the very low stocking of 2 sheep/ ha and (iv) some introduced forages had a much higher yield potential than the currently used cover crops and naturally occurring species at all light levels. The best introduced species are now being evaluated in mixtures under grazing in both conventionally planted and in hedgerow-planted rubber plantations

Tropical Forage Seed Production in Southeast Asia: Current Status and Prospects

The demand for forage seed in southeast Asia has increased in recent years. More than 1,200 tons of seed were produced in Thailand in 1995 with smaller quantities of seed having been produced in China, Lao PDR, Malaysia, Philippines and Indonesia. Large quantities have been produced of Brachiaria ruziziensis, Stylosanthes hamata, Stylosanthes guianensis and Panicum maximum. There are good prospects to increase forage seed production and to develop trade between countries in the southeast Asian region. There is a need to increase seed production of widely adapted species, and expand production of forages for other purposes such as turf amenity planting and erosion control

Enhancing Oral Delivery of Plant-Derived Vesicles for Colitis

Plant-derived vesicles (PDVs) are attractive for therapeutic applications, including as potential nanocarriers. However, a concern with oral delivery of PDVs is whether they would remain intact in the gastrointestinal tract. We found that 82% of cabbage PDVs were destroyed under conditions mimicking the upper digestive tract. To overcome this limitation, we developed a delivery method whereby lyophilized Eudragit S100-coated cabbage PDVs were packaged into a capsule (Cap-cPDVs). Lyophilization and suspension of PDVs did not have an appreciable impact on PDV structure, number, or therapeutic effect. Additionally, packaging the lyophilized Eudragit S100-coated PDVs into capsules allowed them to pass through the upper gastrointestinal tract for delivery into the colon better than did suspension of PDVs in phosphate-buffered saline. Cap-cPDVs showed robust therapeutic effect in a dextran sulfate sodium-induced colitis mouse model. These findings could have broad implications for the use of PDVs as orally delivered nanocarriers of natural therapeutic plant compounds or other therapeutics

FAS ligand expression in inflammatory infiltrate lymphoid cells as a prognostic marker in oral squamous cell carcinoma

Currently, the most important prognostic factor in oral squamous cell carcinoma (OSCC) is the presence of regional lymph node metastases, which correlates with a 50% reduction in life expectancy. We have previously observed that expression of hypoxia genes in the tumor inflammatory infiltrate is statistically related to prognosis in OSCC. FAS and FASL expression levels in OSCC have previously been related to patient survival. The present study analyzed the relationship between FASL expression in the inflammatory infiltrate lymphoid cells and clinical variables, tumor histology, and prognosis of OSCC. Strong FASL expression was significantly associated with lymph node metastases (P = 0.035) and disease-specific death (P = 0.014), but multivariate analysis did not confirm FASL expression as an independent death risk factor (OR = 2.78, 95%CI = 0.81-9.55). Diseasefree and disease-specific survival were significantly correlated with FASL expression (P = 0.016 and P = 0.005, respectively). Multivariate analysis revealed that strong FASL expression is an independent marker for earlier disease relapse and disease-specific death, with approximately 2.5-fold increased risk compared with weak expression (HR = 2.24, 95%CI = 1.08-4.65 and HR = 2.49, 95%CI = 1.04-5.99, respectively). Our results suggest a potential role for this expression profile as a tumor prognostic marker in OSCC patient

Prognostic significance of head and neck squamous cell carcinoma repair gene polymorphism

The aims of this study were to analyze the polymorphisms XRCC1 Arg194Trp, XRCC1 Arg399Gln, XRCC3 Thr241Met, XPC Lys939Gln, ERCC1 Asn118Asn, and RAD51 -98G>C and to verify their influence on radiotherapy response and prognosis of patients with head and neck squamous cell carcinoma (HNSCC). Peripheral blood DNA was extracted from 311 patients and analyzed by PCR-RFLP. Our results showed that in irradiated oral and oropharyngeal patients, the 939Gln allele increased 6-fold local disease relapse risk (OR = 6.04; CI = 1.47-24.88) and over 2-fold the earliness of relapse (HR = 2.63; CI = 1.04-6.70). As for the XRCC3 polymorphism, multivariate analysis showed that the 241Met allele increases over 33-fold local relapse risk (OR = 33.64; CI = 3.23-350.85), over 12-fold earliness of relapse (HR = 12.55; CI = 2.47-63.73) and over 3-fold earliness of death (HR = 3.04; CI = 1.08-8.61). For polymorphism RAD51 -98, multivariate analysis showed that allele C increases over 3-fold the risk of relapse (OR = 3.13; CI = 1.12-8.78) and over 2-fold the earliness of relapse (HR = 2.84; CI = 1.25-6.47). For polymorphism XRCC1 Arg399Gln, multivariate analysis showed that the 399Gln allele increased the risk of local disease relapse for irradiated oral and oropharyngeal patients (OR = 3.35; CI = 1.10-10.13) by over 3-fold. Based on these results, we suggest that these polymorphisms may be useful markers of prognosis in HNSC

The Arthropod Fauna of Oak (Quercus spp., Fagaceae) Canopies in Norway

(1) We document the invertebrate fauna collected from 24 oak canopies in east and west Norway as a contribution to the Norwegian Biodiversity Information Centre’s ‘The Norwegian Taxonomy Initiative’. (2) A snap-shot inventory of the canopies was recorded by means of emitting a mist of natural pyrethrum into the canopies at night using a petrol-driven fogger and collecting the specimens in butterfly nets spread on the ground under the canopy. (3) Almost the entire catch of more than 6800 specimens was identified to 722 species. Out of 92 species new to the Norwegian fauna, 21 were new to science and, additionally, 15 were new to the Nordic fauna. Diptera alone constituted nearly half of the species represented, with 61 new records (18 new species). Additionally, 24 Hymenoptera (one new species), six oribatid mites (two new species) and one Thysanoptera were new to the Norwegian fauna. (4) Our study emphasizes the importance of the oak tree as a habitat both for a specific fauna and occasional visitors, and it demonstrates that the canopy fogging technique is an efficient way to find the ‘hidden fauna’ of Norwegian forests. The low number of red listed species found reflects how poor the Norwegian insect fauna is still studied. Moreover, the implication of the IUCN red list criteria for newly described or newly observed species is discussed.</jats:p