scholarly journals Diversity and Abundance of Bee Flower Visitors of Beans in Borabu Sub-County, Western Kenya

2021 ◽  
Vol 13 ◽  
pp. 24-31
Author(s):  
Lilian N. Nyanumba ◽  
Rebecca N. Karanja ◽  
Mary Gikungu

Globally bees form the main animal pollinators of most crops. Most agricultural crops rely on pollinators, particularly bees for pollination services. Smallholder farmers in Africa commonly use maize/bean intercropping in order to achieve the optimum yields hence providing them with significant food security and economic impacts. Declining of bee colonies due to anthropogenic factors has led to declines in food production in the world. Yet little is known about crop pollination in African countries. In Kenya pollination studies are still scanty, lack harmonisation and only a few crops have been studied. It is against this background that the study was chosen. One administrative sub location was purposively selected. Three plots were selected at equal 1km distance along atransect laid in that sub location. Sampling of 3 plots each of 100m x 100 m was established along transects. Bee sampling was done for 3 months using a sweep net and a bowl trap to collect bees. Diversity was computed using Shannon’s diversity index while abundance was recorded using abundance curves. A total of 992 bee visitors from 2 families and 9 species were collected from the three study farms. High diversity and abundance of bees was recorded. Therefore, farmers, extension workers and other stakeholders should be sensitized and trained on the importance of bee pollination and its contribution to their welfare and on utilization of cost-effective strategies for bee conservation. Key words: Diversity, Abundance, Pollination, Apis, Nyansiongo

1998 ◽  
Vol 37 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Peter Gerdes ◽  
Sabine Kunst

The bioavailability of phosphorus from different sources has been evaluated in the catchment area of the River Ilmenau (Lower-Saxony, Germany) by using algal assays. The P bioavailability describes the different potential of P from various sources of supporting eutrophication. Effluents from sewage treatment plants were highly bioavailable (72% of TP) whereas rainwater (26%) and erosion effluents (30%) showed a low bioavailability. In order to develop effective strategies to minimize P inputs into the river, source specific P bioavailability indices were determined and combined with a P balance to calculate inputs of vioavailable P (BAP) instead of total P (TP). It could be shown that the relative importance of the different P sources changes when applying BAP. Measures to reduce P inputs into the River Ilmenau will take P bioavailability into consideration and therefore lead to a more cost-effective management.


Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1072
Author(s):  
Raquel Cid ◽  
Jorge Bolívar

To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1051
Author(s):  
Jonattan Gallegos-Catalán ◽  
Zachary Warnken ◽  
Tania F. Bahamondez-Canas ◽  
Daniel Moraga-Espinoza

Orally inhaled drug products (OIDPs) are an important group of medicines traditionally used to treat pulmonary diseases. Over the past decade, this trend has broadened, increasing their use in other conditions such as diabetes, expanding the interest in this administration route. Thus, the bioequivalence of OIDPs is more important than ever, aiming to increase access to affordable, safe and effective medicines, which translates into better public health policies. However, regulatory agencies leading the bioequivalence process are still deciding the best approach for ensuring a proposed inhalable product is bioequivalent. This lack of agreement translates into less cost-effective strategies to determine bioequivalence, discouraging innovation in this field. The Next-Generation Impactor (NGI) is an example of the slow pace at which the inhalation field evolves. The NGI was officially implemented in 2003, being the last equipment innovation for OIDP characterization. Even though it was a breakthrough in the field, it did not solve other deficiencies of the BE process such as dissolution rate analysis on physiologically relevant conditions, being the last attempt of transferring technology into the field. This review aims to reveal the steps required for innovation in the regulations defining the bioequivalence of OIDPs, elucidating the pitfalls of implementing new technologies in the current standards. To do so, we collected the opinion of experts from the literature to explain these trends, showing, for the first time, the stakeholders of the OIDP market. This review analyzes the stakeholders involved in the development, improvement and implementation of methodologies that can help assess bioequivalence between OIDPs. Additionally, it presents a list of methods potentially useful to overcome some of the current limitations of the bioequivalence standard methodologies. Finally, we review one of the most revolutionary approaches, the inhaled Biopharmaceutical Classification System (IBCs), which can help establish priorities and order in both the innovation process and in regulations for OIDPs.


2021 ◽  
Vol 43 (1) ◽  
pp. 4-7
Author(s):  
Linda J. Johnston ◽  
Norma Gonzalez-Rojano ◽  
Kevin J. Wilkinson ◽  
Baoshan Xing

Abstract Nanotechnology has developed rapidly in the last two decades with significant effort focused on the development of nano-enabled materials with new or improved properties that offer solutions for current world challenges. The commercialization of products containing engineered nanomaterials (ENM) has progressed much more rapidly than the development of practical approaches to ensure their safe and sustainable use. The lack of adequate detection and characterization techniques and reproducible and validated methods for toxicological studies have been identified as major limitations. The rapid development of ENM of increasing complexity and diversity and concerns over the adequacy of existing regulations also contribute to safety concerns with these materials. The full potential of nanotechnology can only be realized when feasible, cost-effective strategies to ensure a safe-by-design approach, effective risk assessment approaches and appropriate regulatory guidelines are in place.


Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 528
Author(s):  
Frank Mmbando ◽  
Emmanuel Mbeyagala ◽  
Papias Binagwa ◽  
Rael Karimi ◽  
Hellen Opie ◽  
...  

This study analyzes the factors that influence the probability and extent of the adoption of mungbean production technologies in Tanzania, Kenya and Uganda, using multivariate probit and Poisson regression models. The results show that the probability and extent of the adoption of mungbean production technologies are influenced by gender of the household, household size, farm size, livestock size, household assets, access to extension services and access to credit. The study suggests that policy interventions that aimed at targeting women farmers, increasing household asset and information dissemination, such as field demonstrations and training programs, are crucial in enhancing technology adoption among smallholder farmers.


2016 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Lighton Dube

<p>This study analyzes the degree of crop diversification and factors associated with crop diversification among 479 smallholder farmers in Manicaland and Masvingo provinces of Zimbabwe. The Herfindahl index used to estimate diversification, while the Tobit model evaluated factors associated with crop diversification.  The mean crop diversity index is 0.54. On average households in Nyanga and Bikita are the most diversified with indices of 0.48 and 0.49 respectively. The most specialized households are in Mutasa and Chiredzi with indices of 0.62. An analysis by gender shows that male headed households are slightly more diversified than female headed households. The Tobit model indicates that gender of head of household, education, number of livestock units, access to irrigation, membership to a farmers group, access to markets, farming experience, farms on flat terrain, farmer to farm extension, routine extension, agro-ecological zone and household income are significant contributors to increasing crop diversification. In turn, crop specialization is significantly associated with off-farm employment, soil fertility, farmers who are happy with extension contacts per year, farmers trained using the farmer field school approach and farmers who receive NGO extension support.</p>


2017 ◽  
Vol 44 (1) ◽  
pp. 11-17 ◽  
Author(s):  
E. Charles Osterberg ◽  
Gregory Murphy ◽  
Catherine R. Harris ◽  
Benjamin N. Breyer

2021 ◽  
Vol 32 (2) ◽  
pp. 41-58
Author(s):  
F.M. Mwaura ◽  
M. Ngigi ◽  
G. Obare

There are gaps in research needed to enhance policy intervention for rural households’ transitions from traditional biomass to cleaner energy sources. This paper reports on a survey among farmers in western Kenya to assess drivers of cooking energy choices for various key meals; to understand agricultural production factors in cooking energy choices; and to assess energy use homogeneity among varied sub-counties. The study sampled 388 respondents from four heterogeneous rural sub-counties differing in altitude, proximity to public forests, and cultural characteristics. The multinomial logit model analysis showed that significant factors influencing the shift from firewood to LPG for breakfast preparation included access to credit, income, formal employment, and the proportion of adults in the household. Shifting from firewood to crop wastes was significant, influenced by distance covered to collect firewood, and desire for warming houses. The shift from firewood to sticks was influenced by firewood cost, houses owned, and reliance on own farm for woodfuel. Determinants of cooking energy choices for breakfast, lunch and supper were identical. Sticks were seen as an inferior cooking energy source. The adoption of cleaner energy was more associated with breakfast than other meals. Despite the sub-counties’ heterogeneity, no substantial differences were observed among them on drivers of cooking energy choices. Study outcomes were consistent with other concepts associated with cooking energy usage, including the transition energy ladder and energy stacking.


Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1536 ◽  
Author(s):  
Amir Mosavi ◽  
Pinar Ozturk ◽  
Kwok-wing Chau

Floods are among the most destructive natural disasters, which are highly complex to model. The research on the advancement of flood prediction models contributed to risk reduction, policy suggestion, minimization of the loss of human life, and reduction of the property damage associated with floods. To mimic the complex mathematical expressions of physical processes of floods, during the past two decades, machine learning (ML) methods contributed highly in the advancement of prediction systems providing better performance and cost-effective solutions. Due to the vast benefits and potential of ML, its popularity dramatically increased among hydrologists. Researchers through introducing novel ML methods and hybridizing of the existing ones aim at discovering more accurate and efficient prediction models. The main contribution of this paper is to demonstrate the state of the art of ML models in flood prediction and to give insight into the most suitable models. In this paper, the literature where ML models were benchmarked through a qualitative analysis of robustness, accuracy, effectiveness, and speed are particularly investigated to provide an extensive overview on the various ML algorithms used in the field. The performance comparison of ML models presents an in-depth understanding of the different techniques within the framework of a comprehensive evaluation and discussion. As a result, this paper introduces the most promising prediction methods for both long-term and short-term floods. Furthermore, the major trends in improving the quality of the flood prediction models are investigated. Among them, hybridization, data decomposition, algorithm ensemble, and model optimization are reported as the most effective strategies for the improvement of ML methods. This survey can be used as a guideline for hydrologists as well as climate scientists in choosing the proper ML method according to the prediction task.


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