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The economic return for peanut (Arachis hypogaea L.) in Ghana is often low due to limitations in the availability of inputs or their adoption, which are needed to optimize yield. Six experiments were conducted in Ghana in 2020 and 2021 to determine the impact of planting date, cultivar, fertilization, pest management practices, and harvest date on peanut yield, financial return, and pest reaction. A wide range of interactions among these treatment factors were often observed for infestations of aphids (Aphis gossypii Glover); groundnut rosette disease (Umbravirus: Tombusviridaee); millipedes (Peridontopyge spp.); white grubs (Schyzonicha spp.); wireworms (Conoderus spp.); termites (Microtermes and Odontotermes spp.); canopy defoliation as a result of early leaf spot disease caused by Passalora arachidicola (Hori) and late leaf spot caused by Nothopassalora personata (Berk. and M. A. Curtis); and the scarification and boring of pods caused by arthropod feeding. Pod yield and economic return increased for the cultivar Chitaochi and Sarinut 2 when fertilizer was applied and when fertilizer was applied at early, mid-, and late planting dates. Pod yield and economic return increased when a combination of locally derived potassium soaps was used for aphid suppression and one additional hand weeding was used in the improved pest management practice compared with the traditional practice without these inputs. Pearson correlations for yield and economic return were negatively correlated for all pests and damage caused by pests. The results from these experiments can be used by farmers and their advisors to develop production packages for peanut production in Ghana. [ABSTRACT FROM AUTHOR]

SiC vertical MOSFETs are fabricated and characterized with blocking voltages of about 1 kV and a specific on-resistance as low as 8.3 m[omega].[cm.sup.2]. The internal body diode's reverse recovery characteristics have shown injection-limited conduction, which are attributed to the implanted P-anode layers.

The performance of bias stress induced breakdown voltage (BV) slump measurements on DMOSFETs is discussed. Findings reveal that the BV slumped after the DMOSFET was bias stressed at 1200 V for 2 hours at 175 degree Celsius.

Invasive alien species (IAS) continue to shape the global landscape through their effects on biological diversity and agricultural productivity. The effects are particularly pronounced in Sub-Saharan Africa, which has seen the arrival of many IAS in recent years. This has been attributed to porous borders, weak cross border biosecurity, and inadequate capacity to limit or stop invasions. Prediction and early detection of IAS, as well as mechanisms of containment and eradication, are needed in the fight against this global threat. Horizon scanning is an approach that enables gathering of information on risk and impact that can support IAS management. A study was conducted in Ghana to establish two ranked lists of potential invasive alien plant pest species that could be harmful to agriculture, forestry, and the environment, and to rank them according to their potential threat. The ultimate objective was to enable prioritization of actions including pest risk analysis, prevention, surveillance and contingency plans. Prioritisation was carried out using an adapted version of horizon scanning and consensus methods developed for ranking IAS worldwide. Following a horizon scan of invasive alien species not yet officially present in Ghana, a total of 110 arthropod and 64 pathogenic species were assessed through a simplified pest risk assessment. Sixteen species, of which 14 were arthropods and two pathogens, had not been recorded on the African continent at the time of assessment. The species recorded in Africa included 19 arthropod and 46 pathogenic species which were already recorded in the neighbouring countries of Burkina Faso, Côte d'Ivoire, and Togo. The majority of arthropod species were likely to arrive as contaminants on commodities, followed by a sizable number which were likely to arrive as stowaways, while some species were capable of long distance dispersal unaided. The main actions suggested for species that scored highly included full pest risk analyses and, for species recorded in neighbouring countries, surveys to determine their presence in Ghana were recommended. [ABSTRACT FROM AUTHOR]

Presently, high-power soft-switching resonant pole converters, such as the auxiliary resonant commutated pole (ARCP) converter, that have internal dc link voltages above 1.5 kV, can only use gate turn-off thyristors (GTO's) as main switching devices. For these applications, considerable effort has been spent to design, evaluate, and enhance the dynamic performance of high-voltage MOS-controlled thyristors (HVMCT's). It is expected that in the near future HVMCT's, which require little gate power because of their high gate impedance, will gradually replace high-voltage GTO's. The purpose of this paper is to present and summarize key HVMCT characterization results gathered to date as they relate to their dynamic performance during zero-voltage switching. HVMCT devices capable of turning off 300 A and withstanding 3000 V are presented. The paper concludes with a comparison of the soft-switching performance of HVMCT's and GTO's in an ARCP converter phase leg.