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A survey was conducted to provide information on weed types, control strategies, and their estimated costs to smallholder rubber outgrowers in Western Ghana. A total of 80 farmers with rubber trees aged 1–4 years were randomly selected for the study. This represents 10.2% of the total number of farmers (783) who fall within this target group in the districts. The results show that smallholder rubber plantation farmers are dealing with diverse weed species, most of which are reported as global weeds. Chromolaena odorata, Scleria boivinii, and Mimosa pudica were the most reported species. Manual weeding and application of herbicides are the major control methods adopted by the farmers in the study area with a small percentage (16%) also using cover cropping. The two major control methods cost farmers an estimated average amount of Ghc 618.24 ± 26.25 (US $140.51 ± 5.91) for one-time weed control per hectare. The average estimated cost of one-time manual weeding per hectare was higher than that of herbicide application per hectare. This estimated amount is only a fraction of the total economic cost of weeds to the farmers. The farmers are likely to spend more if, for example, the costs of yield loss due to weeds are captured. The study thus indicates that the cost of weed management is high for rubber outgrowers and essentially farmers are investing heavily in weed management to keep weed competition on-plantation relatively low. Given that the core objective of rubber growing is to maximize profits, this study recommends the application of herbicides to control weeds in rubber plantations since average estimated cost of herbicide application per hectare was lower than one-time manual weeding per hectare. This recommendation should, however, be weighed against the possible environmental impact of herbicides, which was not assessed in this study.

Naturalisation risk and the vulnerability of many countries to future plant invasions is predicted to increase with human movement and climate change. Unfortunately, the geographical limitation on studies assessing unintentional human‐vectored dispersal (HVD) has hampered progress in understanding its importance, particularly its probability of introducing species that will become naturalised or invasive. The current paper used an explorative approach to determine if human clothing and vehicles disperse species with higher potential to become invasive globally. The study specifically relies on available database of unintentional human‐vectored seed dispersal and recent studies that considered the outcomes of plant species' interaction with humans around the world. The results indicate that human vehicles and clothing contribute to the spread of many extreme risk and most naturalised species of the world. For example, 55% of the 200 most naturalised species have been reported to be dispersed on vehicle while almost one ‐third (32%) have been reported to be dispersed on clothing. Also, of the 235 extreme risk species 41% have been reported to be dispersed on vehicles and 31% on clothing. The results indicate that graminoids, herbs and species with long‐term seed bank are more dispersed via HVD. Conservation managers and practitioners should consider the role of human‐vectored seed dispersal in the spread of invasive weeds, especially in popular and frequently visited areas. Individuals embracing responsible travel practices and adopting proactive measures and protocols to prevent the accidental transport of seeds can significantly enhance our conservation endeavours in our interconnected global ecosystem. [ABSTRACT FROM AUTHOR]

Influence of chemical composition of sawdust on the nutritional profile of oyster mushrooms (Pleurotus ostreatus) has yet to receive significant research attention. This information will help mushroom growers to select specific sawdust for the production of mushroom with desired dietary preferences. This study assessed the influence of the chemical composition of sawdust on the macronutrients and ash content of the pearl oyster mushrooms. The American Standard for Testing Materials and other widely accepted protocols were used to determine the C-N ratio, pH, lignin, hemicellulose and cellulose contents of mixed sawdust from tropical wood species. The study evaluated the fat, crude fibre, crude protein, carbohydrate, and ash content of the oyster mushroom cultivated on the sawdust. Cellulose constituted the largest component of the sawdust (47.82%), followed by lignin (33.29%). The yield of the mushroom (on 0.05 kg of sawdust) ranged from 490.1 to 540.9 g (biological efficiency: 44–50%); the average carbohydrates constituent in the mushroom was 56.28%. pH of the sawdust influenced the crude protein, carbohydrate, fat and ash content of oyster mushrooms (p<0.05) most significantly. The hemicelluloses also had a significant effect (p<0.05) on the mushroom's minerals, fat and crude fiber content. The study revealed that the mushroom producers would likely obtain high protein content using sawdust with low pH (slightly acidic to slightly basic) in the oyster mushroom. Mushrooms grown on substrates, rich in hemicelluloses, had low fat and high crude fiber content. [ABSTRACT FROM AUTHOR]

Mistletoes are parasitic flowering plants that attack plants like cocoa and kill branches distal to point of attachment. Consequently, cocoa farmers incorporate trees to provide shade to limit germination and establishment of Tapinanthus bangwensis mistletoe species, but without success. This study was conducted in South-Western Ghana to identify causal factors of mistletoe infestation using random forest (RF) regression. Spatial arrangement of cocoa trees was the most important factor explaining mistletoe density, which was significantly higher in farms planted at random than in rows. The results imply that planting cocoa trees in rows could mitigate mistletoe infestation of Ghana's cocoa agroforests. [ABSTRACT FROM AUTHOR]

In the search for alternatives to wood fuel, to meet the bio-energy requirement of an ever-increasing global population, the International Network for Bamboo and Rattan has supported farmers in many tropical countries to establish plantations of Beema bamboo (a tissue-cultured clone from Bambusa vulgaris) and Oxytenanthera abyssinica for bio-energy production. The quality of these species as solid biofuels is unknown due to the absence of data on their physico-thermal and emission characteristics. Using the American Standard for Testing and Materials and other internationally accepted standards, their ultimate and proximate analysis, and physico-thermal and emission properties were evaluated. Beema bamboo and O. abyssinica have high Hydrogen, organic and fixed Carbon contents and low quantities of ash, moisture content, volatile matter, Oxygen, Nitrogen and Sulphur. This will contribute to their heating values and low oxide emissions. Based on their High Heating Values (Beema bamboo = 23.22 MJ/kg; O. abyssinica = 23.26 MJ/kg), the species will be suitable for high energy-using applications. The Particulate Matter and Carbon Monoxide concentrations (Beema bamboo: 90 ug/m3 and 2.83 ppm respectively; O. abyssinica: 77.33 ug/m3 and 3.20 ppm respectively) are lower than the threshold (35000 ug/m3 and 9 ppm respectively) approved by the United States Environmental Protection Agency. These properties make the species good raw materials for solid biofuel which is safe for indoor use. Their use will contribute to reducing pressure on tropical forests for wood fuel and the health hazards associated with fossil fuel use. [ABSTRACT FROM AUTHOR]

The alarming global deforestation rate has great impacts on the output of the Pulp and paper Industry since wood is the principal papermaking fiber material. Although, generally, bamboo is an alternative cellulolytic fiber source, the species and culm age have great effects on its papermaking potential. Based on the methods by the International Association of Wood Anatomists (IAWA), this work assessed the characteristics of fibers from the axial culm sections of six-month plantation-grown Oxythenantera abyssinica and Beema bamboo (which was cloned from Bambusa balcoaa) for paper production. The lengths of the fibers ranged from 1.89 to 2.39 mm while the diameters were 0.025–0.031 mm. The fiber lumen diameter and wall thickness were 0.014–0.018 mm and 0.004–0.006 mm, respectively. Fibers from the species had their runkle ratios below 1, slenderness ratios above 70 and flexibility ratios above 50. These characteristics compare well with the recommendations for fibers often used for the production of packaging, writing and printing papers. Establishment of plantations of Beema bamboo and O. abyssinica is encouraged as they will serve as good raw material base for the paper industry within six months of planting. Additionally, their planting will contribute to meeting Sustainable Development Goals 1 and 13. [ABSTRACT FROM AUTHOR]

Recent estimates indicate that over 291 million hectares of the Earth's land area are occupied by forest plantations, representing 7% of the world's forest area and 2% of the world's land area. In Ghana, a substantial amount of degraded land found in hilly areas has been used to establish teak plantations for commercial wood and carbon benefits. Information on the potential influence of topography and soil properties on tree growth and carbon stocks in these plantations is however limited. The study was carried out to assess the influence of elevation on tree growth parameters and carbon stocks in a 7-year-old teak stand and also determined the differences in soil properties along the elevation gradient and its influence on biomass and carbon stocks. Although stand density was statistically similar for the three elevations, tree, diameter, and basal area significantly differed among the three elevations. They were higher at the valley than the mid-slope and the summit. The aboveground biomass and belowground biomass were also significantly higher at the valley compared to the mid-slope and summit. Measured SOC and CEC values between the three elevations showed no significant difference while a positive significant correlation between soil depth and biomass along the altitudinal gradient was observed. Overall, the mean percentage of nitrogen in the soil, pH, potassium, sodium levels, hydrogen, and aluminum varied significantly among the three elevations. Our study suggests that in mountainous areas teak stands in valleys are likely to produce higher biomass and carbon stocks than those in higher elevations; therefore, for better accuracy in biomass and carbon stocks estimations, site elevation should be taken into consideration during carbon stock assessments. [ABSTRACT FROM AUTHOR]

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]

Forest cover loss, particularly those arising from deforestation and forest degradation, is largely driven by human activities and has attracted global attention over the decades. Globally, countries have adopted strategies to manage and conserve forests in response to these human disturbances. Ghana's strategy to ensure sustainable management of the forest and its estate was to zone the forest into management regimes based on the resource availability and the object of managing those particular areas. Whilst forest degradation and its drivers and actors have been widely reported in Ghana, it is not known how forest management regimes influence these issues. Focusing on four forest reserves in the high forest zone of Ghana, this paper used interviews of key forest stakeholders, analysis of Forestry Commission field reports, and field verification to demonstrate the effect of forest management regimes on drivers of forest degradation. A combination of many proximate and underlying factors was observed to drive degradation in a synergetic way. The main drivers which were identified and their corresponding actors varied and manifested differently across management regimes. The strive by forest landowners to earn revenue from the protected forest, perceived unfair payment of ground rents for protected areas by Timber Utilization Contract holders, poor forest management practices on the part of forestry personnel, nondeterrent penalties, poor forest monitoring, the granting of compartment re-entry permits to harvest residual yield, overdependence on few species, weak enforcement of forest regulations, and perceived corruption on the part of forestry officials were the major underlying factors that impact on how the drivers manifested in various regimes. Our study reveals that the primary forest stakeholders of the country are the main actors of forest degradation and have developed various means convenient for specific regimes that enable them to benefit from the forest at the expense of conservation. [ABSTRACT FROM AUTHOR]

The introduction of a non-native fish species into an aquatic ecosystem presents significant ecological risks if the species is able to successfully integrate into the ecosystem. Lake Bosomtwe in Ghana is an impact crater lake which contains an endemic and a near-endemic cichlid species. Following the establishment of an intensive Nile tilapia (Oreochromis niloticus) cage aquaculture facility on the Lake in 2012 and it closure in 2015, there have been several unconfirmed reports of the capture of O. niloticus from Lake Bosomtwe by local fishermen. On 6th February 2020, the first documented observations of O. niloticus in the natural environment of Lake Bosomtwe were made using seine net catches. Nine more seining activities were carried out between 6th February and 17th April, 2020, and the presence of the O. niloticus was confirmed during all sampling events. Oreochromis niloticus constituted between 2 and 10% of the captured cichlid species composition. The introduction of the species warrants larger-scale comprehensive studies on the possible detrimental interactions with native species, and on changes to ecosystem function. [ABSTRACT FROM AUTHOR]

Natural forests are disappearing in many tropical countries, resulting in loss of biodiversity and erosion of forest-dependent livelihoods. The maintenance and restoration of forests as well as a search for alternative natural resources that can concurrently improve the environment and enhance incomes of local communities has become crucial. Bamboo is suggested as a resource, which could substitute trees for socio-economic and ecological purposes in developing countries in the (sub)tropics. However, the relative importance of bamboos and trees for socio-economic and ecological purposes in bamboo-growing communities is not yet studied. Here, we present a study conducted to compare the socio-economic and ecological benefits of bamboo and trees from the perspectives of three bamboo-growing communities in the Wassa East District of Ghana. The compared benefits were ranked on a five-point Likert scale and significance of differences was tested at the 95% confidence level. For socio-economic benefits, trees were ranked significantly higher than bamboo for domestic energy, medicinal use and commercial harvesting; however, furniture, building and construction were not significantly different. For ecological benefits, bamboo was ranked significantly higher than trees for erosion control and riverbank protection. Trees, on the other hand, were ranked significantly higher than bamboo for biodiversity conservation, carbon sequestration and oxygen generation. The results imply that transforming bamboo into suitable products to meet communities' energy needs could alleviate pressure on trees in natural forests. [ABSTRACT FROM AUTHOR]

This paper sought to determine how different forest management regimes influence the pattern of forest degradation at different periods in Ghana. The paper tested the hypotheses that timber production forests degrade faster than protection forests and forest degradation slows down with time. For monitoring the changes in forest cover, Landsat TM, ETM+ and Landsat 8 with a spatial resolution of 30 m were used in the mapping of land use/land cover for the periods 1990, 2000, 2010 and 2014 using supervised classification technique. The results showed that forest degradation occurred at different rates within the period and was more rapid from 1990 to 2000 than from 2000 to 2010. Protected forests and Globally Significant Biodiversity Areas (GSBAs) declined in forest quality at the same rate as timber production forests and did not benefit from any extra protective measures. New strategies should be found to manage protection forests and GSBAs to ensure their optimum protection. [ABSTRACT FROM AUTHOR]

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Humans can unintentionally disperse plant propagules (herein referred to as seeds) including weed seeds from clothing when hiking. There is limited experimental or observational information, however, about unintended human-mediated seed dispersal, particularly from different types of clothing. We experimentally assessed the probability of seed detaching from socks and trousers along a 5 km standardized route for eight common environmental weeds: B idens pilosa L., C hloris gayana Kunth., C onyza canadensis L., C ynodon dactylon L., D rymaria cordata ( L.) Willd. ex Schult., P oa annua L., P aspalum urvillei Steud. and S porobolus elongatus R. Br. Seed detachment varied among species on both types of clothing, but seeds more easily detached from trousers than socks. When different models were fitted to the data, a three-parameter generalized exponential model with curves provided the best fit. The curves were leptokurtic, with peak close to the seed source and a long flat tail, which indicates that most seeds dispersed from clothing fall close (within 5 m) to the point of attachment with only a small proportion of seeds dispersed over long distances. Combining attachment and detachment data for the same species, we estimated the actual numbers of seeds potentially dispersed over a hike of 5 km. The study indicates that most seeds are likely to be dispersed at the start of walks, although the actual number of seeds will vary depending on several factors such as the behaviour of the hiker and the amount of weed seeds present at the start of the walk. Those few seeds dispersed much further may, however, be more important in terms of plant invasions. Covering socks with gaiters and avoiding walking through weedy areas such as road edges and car parks before starting walks could minimize the risk of seeds attaching to clothing and hence being dispersed. [ABSTRACT FROM AUTHOR]

Weeds are a major threat to biodiversity globally degrading natural areas of high conservation value. But what are our attitudes about weeds and their management including weeds in national parks? Do we know what a weed is? Do we consider weeds a problem? Do we support their management? Are we unintentionally spreading weeds in parks? To answer these questions, we surveyed visitors entering a large popular national park near the city of Brisbane, Australia. Park visitors were knowledgeable about weeds; with >75% correctly defining weeds as ‘plants that grow where they are not wanted’. About 10% of the visitors, however, provided their own sophisticated definitions. This capacity to define weeds did not vary with people’s age, sex or level of education. We constructed a scale measuring visitors’ overall concern about weeds in parks using the responses to ten Likert scale statements. Over 85% of visitors were concerned about weeds with older visitors, hikers, and those who could correctly define weeds more concerned than their counterparts. The majority think visitors unintentionally introduce seeds into parks, with many (63%) having found seeds on their own clothing. However, over a third disposed of these seeds in ways that could facilitate weed spread. Therefore, although most visitors were knowledgeable and concerned about weeds, and support their control, there is a clear need for more effective communication regarding the risk of visitors unintentionally dispersing weed seeds in parks. [ABSTRACT FROM AUTHOR]

To assess the diversity of weed seeds dispersed via horse dung, we reviewed 15 studies on seed germination from horse dung - six from Europe, four from North America, three from Australia and one study each from Africa and Central America. Seed from 249 species from 43 families have been identified germinating from horse dung. Almost two-thirds of the species were forbs and 33% graminoids, with over half being perennials and 32% annuals. Nearly every species (totalling 99% of those reviewed) is considered a weed somewhere, with 47% recorded as invasive and 19% international environmental weeds. Of the 2739 non-native plants that are naturalized in Australia, 156 have been shown to germinate from horse dung. This includes 16 of the 429 listed noxious weeds in Australia and two weeds of national significance. Seed from 105 of the 1596 invasive/noxious plant species in North America have also been identified germinating from horse dung. Seed traits including seed size, length, width and mass affect dispersal via horse dung. Habitat disturbance from trampling facilitates germination of seedlings from dung in both natural and experimental studies. Some studies found that plants germinating from dung reach maturity and flower, while others found plants did not survive due to unfavourable growing conditions in the field. The diversity of species with seed that can germinate from horse dung highlights the potential of horses to disperse a range of seed over long distances. Whether such dispersal is beneficial or harmful depends on the plant and the context in which it germinates. To maintain the conservation value of protected areas, it is important to understand and manage the different potential weed dispersal vectors, including horses. [ABSTRACT FROM AUTHOR]

Humans can contribute to the long-distance dispersal of many plants, including weeds. We assessed the distance for which seed remained attached to the socks and trouser legs of walkers. The experiment in Kakadu National Park, Australia used seed of the Australian native Black Spear Grass ( Heteropogon contortus) as a surrogate for the potential dispersal of weed seed. Two models were fitted to the data, with a double exponential model fitting the data slightly better than a power exponential model. Although 19% of seed were dispersed within the first 5 m of walking, most (55%) seed remained attached to socks and trousers at 5 km. Humans may, therefore, unintentionally carry and eventually disperse this grass and other invasive grasses with similar long awns and pointed seeds over long distances. Implementing strategies to reduce the potential for seed to attach to walkers (gaiters) and reduce potential dispersal (removal and careful disposal of seed) would reduce the risks posed by this type of human-mediated seed dispersal. [ABSTRACT FROM AUTHOR]

Understanding the attitude of stakeholders towards forest management is important for the conservation of forests. In this paper we examine attitudes of primary stakeholders towards forest conservation management in Ghana, with Subri Forest Reserve as the study area. Using a survey methodology, 300 households from 10 communities around the reserve were randomly selected and interviewed with structured questionnaires. The results revealed that primary stakeholders have positive attitudes towards forest management and this was not dependent on the location of the community. They support sanctioning people who degrade the forest and accept the need to get a permit before harvesting. However, they are not in favour of strict protection of the reserve. Their attitude towards forest management is influenced by their perception of forest values, concern about degradation of the reserve, economic benefits they derive from the reserve, exposure to resource-use conflicts and membership of conservation organizations. Our findings suggest that primary stakeholders are interested in forest conservation management. But, to achieve sustainable development, it will be necessary to identify the types and quantity of forest products used and their economic significance and to develop initiatives that will support rural livelihoods. [ABSTRACT FROM PUBLISHER]

This dataset provides the Global Naturalized Alien Flora (GloNAF) database, version 1.2. GloNAF represents a data compendium on the occurrence and identity of naturalized alien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts, islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including 381 islands). The dataset is based on 210 data sources. For each taxon‐by‐region combination, we provide information on whether the taxon is considered to be naturalized in the specific region (i.e. has established self‐sustaining populations in the wild). Non‐native taxa are marked as "alien", when it is not clear whether they are naturalized. To facilitate alignment with other plant databases, we provide for each taxon the name as given in the original data source and the standardized taxon and family names used by The Plant List Version 1.1 (http://www.theplantlist.org/). We provide an ESRI shapefile including polygons for each region and information on whether it is an island or a mainland region, the country and the Taxonomic Databases Working Group (TDWG) regions it is part of (TDWG levels 1–4). We also provide several variables that can be used to filter the data according to quality and completeness of alien taxon lists, which vary among the combinations of regions and data sources. A previous version of the GloNAF dataset (version 1.1) has already been used in several studies on, for example, historical spatial flows of taxa between continents and geographical patterns and determinants of naturalization across different taxonomic groups. We intend the updated and expanded GloNAF version presented here to be a global resource useful for studying plant invasions and changes in biodiversity from regional to global scales. We release these data into the public domain under a Creative Commons Zero license waiver (https://creativecommons.org/share-your-work/public-domain/cc0/). When you use the data in your publication, we request that you cite this data paper. If GloNAF is a major part of the data analyzed in your study, you should consider inviting the GloNAF core team (see Metadata S1: Originators in the Overall project description) as collaborators. If you plan to use the GloNAF dataset, we encourage you to contact the GloNAF core team to check whether there have been recent updates of the dataset, and whether similar analyses are already ongoing. [ABSTRACT FROM AUTHOR]

When traveling in cars, we can unintentionally carry and disperse weed seed; but which species, and where are they a problem? To answer these questions, we systematically searched the scientific literature to identify all original research studies that assess seed transported by cars and listed the species with seed on/in cars. From the 13 studies that fit these criteria, we found 626 species from 75 families that have seed that can be dispersed by cars. Of these, 599 are listed as weeds in some part of the world, with 439 listed as invasive or naturalized alien species in one or more European countries, 248 are invasive/noxious weeds in North America, 370 are naturalized alien species in Australia, 167 are alien species in India, 77 are invasive species in China and 23 are declared weeds/invaders in South Africa. One hundred and one are classified as internationally important environmental weeds. Although most (487) were only recorded once, some species such as Chenopodium album, Poa pratensis and Trifolium repens were common among studies. Perennial graminoids seem to be favoured over annual graminoids while annual forbs are favoured over perennial forbs. Species characteristics including seed size and morphology and where the plants grew affected the probability that their seed was transported by cars. Seeds can be found in many different places on cars including under the chassis, front and rear bumpers, wheel wells and rims, front and back mudguards, wheel arches, tyres and on interior floor mats. With increasing numbers of cars and expanding road networks in many regions, these results highlight the importance of cars as a dispersal mechanism, and how it may favour invasions by some species over others. Strategies to reduce the risk of seed dispersal by cars include reducing seed on cars by mowing road verges and cleaning cars. [ABSTRACT FROM AUTHOR]

In this work, for the first time, we demonstrate light control of a therapeutic protein's release from a depot in the subcutaneous layer of the skin. The subcutaneous layer is a standard location for therapeutic protein depots due to its large size and ease of access, but prior attempts to utilize this space failed because insufficient light can reach this deeper layer. An analysis of existing biophysical literature suggested that an increase of photoactivation wavelength from 365 to 500 nm could allow an increase of depot irradiation in the subcutaneous by >100-fold. We therefore used a green light-activated thio-coumarin-based material and demonstrated robust release of a therapeutic, insulin, in response to skin illumination with an LED light source. We further demonstrated that this release is ultrafast, as fast or faster than any commercially used insulin, while maintaining the native insulin sequence. This release of insulin was then accompanied by a robust reduction in blood glucose, demonstrating the retention of bioactivity despite the synthetic processing required to generate the material. In addition, we observed that the material exhibits slow basal release of insulin, even in the absence of light, potentially through biochemical or photochemical unmasking of insulin. Thus, these materials can act much like the healthy pancreas does: releasing insulin at a slow basal rate and then, upon skin irradiation, releasing an ultrafast bolus of native insulin to reduce postprandial blood glucose excursions.

Introduction: Ocular barriers hinder drug delivery and reduce drug bioavailability. This article focuses on enhancing drug absorption across the corneal and conjunctival epithelium. Both, transporter targeted prodrug formulations and nanomicellar strategy is proven to enhance the drug permeation of therapeutic agents across various ocular barriers. These strategies can increase aqueous drug solubility and stability of many hydrophobic drugs for topical ophthalmic formulations., Areas Covered: The article discusses various ocular barriers, ocular influx, and efflux transporters. It elaborates various prodrug strategies used for enhancing drug absorption. Along with this, the article also describes nanomicellar formulation, its characteristic and advantages, and applications in for anterior and posterior segment drug delivery., Expert Opinion: Prodrugs and nanomicellar formulations provide an effective strategy for improving drug absorption and drug bioavailability across various ocular barriers. It will be exciting to see the efficacy of nanomicelles for treating back of the eye disorders after their topical application. This is considered as a holy grail of ocular drug delivery due to the dynamic and static ocular barriers, restricting posterior entry of topically applied drug formulations.