A Rapid, Simple DNA Mismatch Repair Substrate Construction Method

A more flexible and higher-yielding in vitro DNA mismatch repair (MMR) substrate construction method, which was developed initially by Wang and Hays, is described for the construction of a nucleotide-based chemical mismatch (G/IU) and a G/T mismatch. Our modifications use the combination of two endonuclease enzymes (NheI and BciVI) and two new redesigned plasmids (pWDAH1A and pWDSH1B). In our modified methodology, plasmids are initially digested with the nicking endonucleases, followed by the streptavidin treatment. The mismatch-containing oligo is then annealed to the gap DNA and finally ligated to produce a mismatch-containing DNA substrate. We report a high efficiency (up to 90%) of these mismatch substrates and confirm recognition using a functional assay. These modifications, coupled with the use of the redesigned plasmids, can be applied for the construction of other types of chemically induced mismatches as well as insertion-deletion loops for future in vitro studies of MMR processing by our group and others

Design and Implementation of a Short Message Service Based Remote Controller

Safeguarding our home appliances has become an issue when dealing with an advancement and growth of an economy. This research focuses on the controlling of home appliances remotely when the user is away from the house. The system is Short Message Service (SMS) based and uses wireless technology to revolutionize the standards of living. It provides ideal solution to certain problems faced by home owners in daily life. Due to its wireless nature, it is more adaptable and cost-effective. The research is divided into two sections; the hardware and the software sections. The hardware section consists of the Global System for Mobile Communications (GSM) modem module, The Control module, the Appliance module, the Liquid Crystal Display (LCD) module and the power supply module. The GSM modem receives the message sent by the person who wishes to operate any of the connected appliances, it then forwards it to the microcontroller, and the microcontroller decodes the message, switches on or switches off the appropriate appliance, updates the LCD and sends a feedback to the mobile phone via the GSM modem. Overall, the work employs The ATmega16 microcontroller, relays, a programmer to program the microcontroller, a mobile phones and a GSM modem. The AT commands is used to handle communication between the modem and the ATmega16 microcontroller. Flow code is used for the programming of the microcontroller. The overall work was implemented with a constructed work, tested working and perfectly functional.Keywords: Short Message Service, Global System for Mobile Communications, Remote Control, Electronic Circuit Design

Pre-Release Consumption of Methyl Eugenol Increases the Mating Competitiveness of Sterile Males of the Oriental Fruit Fly, Bactrocera dorsalis, in Large Field Enclosures

The sterile insect technique may be implemented to control populations of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), when environmental concerns preclude widespread use of chemical attractants or toxicants. The goal of the present study was to evaluate whether the mating competitiveness of sterile B. dorsalis males could be increased via pre-release feeding on methyl eugenol. Males of the oriental fruit fly are strongly attracted to this plant-borne compound, which they ingest and use in the synthesis of the sex pheromone. Previous studies conducted in the laboratory and small field-cages have shown that males given methyl eugenol produce a more attractive pheromone for females and have a higher mating success rate than males denied methyl eugenol. Here, levels of egg sterility were compared following the release of wild-like flies and either methyl eugenol-fed (treated) or methyl eugenol-deprived (control) sterile males in large field enclosures at four over flooding ratios ranging from 5:1 to 60:1 (sterile: wild-like males). Treated sterile males were fed methyl eugenol for 1–4 h (depending on the over flooding ratio tested) 3 d prior to release. Eggs were dissected from introduced fruits (apples), incubated in the laboratory, and scored for hatch rate. The effect of methyl eugenol was most pronounced at lower over flooding ratios. At the 5:1 and 10:1 over flooding ratios, the level of egg sterility observed for treated, sterile males was significantly greater than that observed for control, sterile males. In addition, the incidence of egg sterility reported for treated sterile males at these lower over flooding ratios was similar to that noted for treated or control sterile males at the 30:1 or 60:1 over flooding ratios. This latter result, in particular, suggests that pre-release feeding on methyl eugenol allows for a reduction in the number of sterile flies that are produced and released, thus increasing the cost-effectiveness of the sterile insect technique

Advancing an interdisciplinary framework to study seed dispersal ecology

Although dispersal is generally viewed as a crucial determinant for the fitness of any organism, our understanding of its role in the persistence and spread of plant populations remains incomplete. Generalizing and predicting dispersal processes are challenging due to context dependence of seed dispersal, environmental heterogeneity and interdependent processes occurring over multiple spatial and temporal scales. Current population models often use simple phenomenological descriptions of dispersal processes, limiting their ability to examine the role of population persistence and spread, especially under global change. To move seed dispersal ecology forward, we need to evaluate the impact of any single seed dispersal event within the full spatial and temporal context of a plant’s life history and environmental variability that ultimately influences a population’s ability to persist and spread. In this perspective, we provide guidance on integrating empirical and theoretical approaches that account for the context dependency of seed dispersal to improve our ability to generalize and predict the consequences of dispersal, and its anthropogenic alteration, across systems. We synthesize suitable theoretical frameworks for this work and discuss concepts, approaches and available data from diverse subdisciplines to help operationalize concepts, highlight recent breakthroughs across research areas and discuss ongoing challenges and open questions. We address knowledge gaps in the movement ecology of seeds and the integration of dispersal and demography that could benefit from such a synthesis. With an interdisciplinary perspective, we will be able to better understand how global change will impact seed dispersal processes, and potential cascading effects on plant population persistence, spread and biodiversity

Employing plant functional groups to advance seed dispersal ecology and conservation

Seed dispersal enables plants to reach hospitable germination sites and escape natural enemies. Understanding when and how much seed dispersal matters to plant fitness is critical for understanding plant population and community dynamics. At the same time, the complexity of factors that determine if a seed will be successfully dispersed and subsequently develop into a reproductive plant is daunting. Quantifying all factors that may influence seed dispersal effectiveness for any potential seed-vector relationship would require an unrealistically large amount of time, materials and financial resources. On the other hand, being able to make dispersal predictions is critical for predicting whether single species and entire ecosystems will be resilient to global change. Building on current frameworks, we here posit that seed dispersal ecology should adopt plant functional groups as analytical units to reduce this complexity to manageable levels. Functional groups can be used to distinguish, for their constituent species, whether it matters (i) if seeds are dispersed, (ii) into what context they are dispersed and (iii) what vectors disperse them. To avoid overgeneralization, we propose that the utility of these functional groups may be assessed by generating predictions based on the groups and then testing those predictions against species-specific data. We suggest that data collection and analysis can then be guided by robust functional group definitions. Generalizing across similar species in this way could help us to better understand the population and community dynamics of plants and tackle the complexity of seed dispersal as well as its disruption

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Supermarket ginger powder increases the mating success of mass-reared males of the Mediterranean fruit fly

A series of studies has shown that exposure to the aroma of ginger root oil (Zingiber officinale, GRO hereafter) enhances the mating success of mass-reared, sterile males of the Mediterranean fruit fly (medfly), Ceratitis capitata. The use of GRO to enhance male mating competitiveness appears to represent a simple means to increase the efficacy of the Sterile Insect Technique (SIT) against this pest. However, the relatively high cost of GRO, along with its restricted commercial availability, may preclude its use in SIT programs with limited budgets and/or no domestic supply of the oil. Consequently, we assessed the effectiveness of supermarket-brand ginger powder, as a potentially less expensive and more widely available substitute for GRO, by comparing the mating success of powder-exposed (treated) and non-exposed (control) sterile males in competition against males from a recently established colony for matings with females from this same colony. In one set of experiments, sterile males were exposed to 2 or 10 g of the ginger powder placed inside storage boxes. In a second set, 1 or 2 g of powder was added to the sugar-agar food block placed on the storage boxes, and the food block was applied on the same day as pupal placement or on the day of peak adult emergence (2 d later). Treated sterile males achieved a significantly greater proportion of total matings than control sterile males at both doses of ginger powder in both sets of experiments, except that ginger powder had no detectable effect (at either dose) when added to food blocks placed on boxes on the same day as pupal placement. The cost of applying GRO to individual storage boxes is compared with that of ginger powder

Exposure to ginger root oil decreases capture of male Mediterranean fruit flies (Diptera: Tephritidae) in Trimedlure-baited traps

Detection programs for pestiferous tephritid fruit flies rely on traps baited with either natural or synthetic food substances, or so-called male lures. While studies on several tephritid species have demonstrated that protein feeding reduces subsequent attraction to protein food baits, comparable data for male lures are scant and largely restricted to the genus Bactrocera. Ginger root oil (GRO) is attractive to males of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and males exposed to this oil’s scent exhibit heightened mating competitiveness. Because of this increased mating success, several sterile male release programs against C. capitata now include pre-release, GRO exposure as part of their standard operating procedures. However, the impact of such exposure on subsequent trap capture has received little study. The purpose of the present study was to measure the effect of GRO exposure on subsequent capture of sterile male medflies in trimedlure-baited traps in two fruit orchards in Hawaii. At each study site, 600 control (non-exposed) and 600 treated (GRO-exposed) males from a mass-reared, genetic sexing strain were released per replicate from a central release point, and trap captures were scored 2 d post-release for eight trimedlure- baited Jackson traps placed in a circular array around the release point. At both orchards, control males were, on average, captured in significantly greater numbers than treated males. This result did not appear to reflect differential mortality between the male types: mortality in screen cages under field conditions was similar over a 48 h period for control and treated males. Implications of these findings for sterile release programs are discussed

Development of Instructional Package on Cassava Enterprises for the Training of Secondary School Graduates in Ebonyi State Skill Acquisition Centres

The cassava enterprise aspect of agricultural skill acquisition does not exist in the state skill acquisition centre for training secondary school graduates. This study therefore sought to develop work-skills in cassava enterprises for training of secondary school graduates in Ebonyi State skill acquisition centers. Three research questions guided the study. Survey research design was adopted. The population for the study was 500 made up of 450 registered cassava farmers and 50 agricultural science teachers. Simple random sampling technique was used to select 153 respondents. The instrument was a questionnaire used to elicit information from the respondents for developing the training package. Three experts validated the instrument. Data collected through the instrument were analyzed using mean and standard deviation for answering research questions. The results indicate 16 work-skills on cassava production practices, 10 work-skills on processing and 8 work-skills on marketing activities. These work-skills formed the training package. It was then recommended that the administrators of skill acquisition should use the training package for training. The state government should mobilize secondary school graduates for the training on the identified work-skills in the skill training centers. Keywords: instructional package, cassava enterprise, training, graduates, skill acquisition DOI: 10.7176/JEP/13-9-03 Publication date:March 31st 202

Application of Orange Oil to Pre-Release Holding Boxes Increases the Mating Success of Sterile Males of the Mediterranean Fruit Fly in Field Cage Trials (Diptera: Tephritidae)

Previous research showed that exposure to the aroma of orange oil (Citrus sinensis L.) increased the mating success of male Mediterranean fruit flies (medfly), Ceratitis capitata (Wiedemann). This work, however, involved the exposure of small groups of males (n = 25) in small containers (volume 400 ml). In implementing the Sterile Insect Technique (SIT), several programs use plastic adult rearing containers (PARC boxes, 0.48 by 0.60 by 0.33 m) to hold newly emerged males before release (≈ 36,000 males per box). The objective of this study was to determine whether the application of orange oil to individual PARC boxes increases the mating competitiveness of sterile C. capitata males. Orange oil was applied to paper placed on the screened opening on the top of PARC boxes. Two doses (0.25 and 1.0 ml) were tested, and the paper was either covered by a Petri dish lid (to reduce volatilization) or was left uncovered. Using field cages, we ran mating trials in which oil-exposed (treated) or non-exposed (control) sterile males competed against males from a recently established (from wild flies) colony for females from the same colony. In all trials, the wild-derived males obtained significantly more matings than the sterile males. In those trials involving uncovered, oil-laden paper, there was no difference in mating success between treated and control sterile males. However, when the paper was covered, the treated males obtained significantly more matings than the control males at both doses. These results are compared with similar, previously conducted experiments involving ginger root oil, and the potential use of orange oil in medfly SIT is discussed