Sedimentological and tectono-stratigraphic characterisation of a shallow-marine reservoir, ‘Dona’ Field, offshore Niger Delta

The ‘Dona’ field is located in the shallow offshore Coastal Swamp depobelt, western Niger Delta. The field contains multiple, stacked shallow-marine reservoir intervals of Miocene to early Pliocene age in the Agbada Formation. The area surrounding the field is characterised by a series of synthetic, listric normal faults that strike north-northwest to south-southeast and dip southwest. These faults show stratigraphic thickening in their hangingwalls, indicating growth, and are associated with the development of rollover anticlines, which define the trap configuration of the ‘Dona’ field. Spatio-temporal variations in stratigraphic expansion indicate that growth faulting started in more landward (northeasterly) locations and migrated progressively basinward (southwestward). These variations are consistent with growth faulting due to gravity-induced shale diapirism, potentially driven by overall progradation of the Niger Delta. Core and wireline-logs from a representative reservoir interval contain a facies assemblage and stratigraphic architecture developed under a mixed-influence depositional process regime, which was dominated by wave processes but influenced by tidal processes. Wave-dominated shoreface deposits occur in a series of coarsening- and shallowing-upward parasequences that are laterally continuous over the reservoir but are locally erosionally truncated by fining-upward tidal channel-fill deposits. The mixed-influence process regime may reflect spatial variations in the dominance of wave, tide and fluvial processes, as in the modern Niger Delta, and/or temporal variations between a regressive, wave-dominated regime and a transgressive, tide-dominated regime. Sedimentological heterogeneities are present across a range of scales, and their distribution reflects the mixed-influence depositional process regime

Advanced leiomyosarcoma of the uterus: a case report and literature review

Uterine leiomyosarcoma is a rare malignancy accounting for 1-2% of uterine malignancies with an annual incidence of 0.5-7 per 100,000 women. It occurs mostly between the 5th to 7th decades of life hence found more among postmenopausal women.  The aetiology is mostly unknown however, in 0.2% of cases, it originates from sarcomatous degeneration in a pre-existing benign uterine fibroid. Leiomyosarcoma can be mistaken for uterine leiomyoma also known as the uterine fibroid.  It is an aggressive tumour that has a poor prognosis, with or without treatment. This case report aimed to report and discuss the occurrence of leiomyosarcoma as a differential diagnosis of abnormal uterine bleeding in this environment among other conditions. This will bring to the fore awareness among gynaecologists, pathologists, radiologists and oncologists that leiomyosarcoma of the uterus, though rare, should be considered in cases of menorrhagia with suspected uterine fibroid to avoid mistaking it for a diagnosis of uterine fibroid/leiomyoma. It is, therefore, imperative to consider leiomyosarcoma in a pre-menopausal and perimenopausal women diagnosed of abnormal uterine bleeding with symptomatic uterine fibroid. MRI serves as a good tool in differentiating the two pathologies.

Isolation and Screening of Laccase-producing Fungi from Sawdust-contaminated Sites in Ado-Odo Ota, Ogun State, Nigeria

The environmental imbalance exerted by the continuous release of phenolic substances necessitates a return of polluted sites to natural and safe status. In this study, fungal isolates obtained from sawdust-contaminated soils were screened for laccase production capacities, using tannic acid, as an index to the bio-stimulatory potentials of the sawdust. Soil and sawdust samples collected from wood-processing plants in Morogbo-Agbara (M), Iju (I), and Oja (O) of Ado-Odo/Ota, Ogun State, Nigeria were subjected to physicochemical analysis. The phenolic content estimated using gallic acid calibration curve, showed 0.90%, 0.79% and 0.33% for the soil samples labeled MSL, ISL, OSL, respectively. Phenol content was observed to be 0.63%, 0.91%, and 0.53% for sawdust samples labeled MSD, ISD, OSD, respectively. In the same labeling order, the percentage nitrogen content was 0.77%, 0.38%, and 0.21% for soil; and 0.0025%, 0.0035% and 0.0028% for sawdust; while the percentage carbon was 0.25%, 0.62% and 0.49% for soil samples; and 88.11%, 85.56%, and 88.69% for the sawdust samples. Fungal species of Aspergillus, Penicillium, Candida and Saccharomyces among the ten isolates presented a positive reaction for laccase production by showing a brownish-black coloration. The ability of the fungal isolates to produce laccase makes them useful laccase sources for industrial and environmental application

A Tale of Two Markets: How Lower-end Borrowers Are Punished for Bank Regulatory Failures in Nigeria

In 2009, the Nigerian banking system witnessed a financial crisis caused by elite borrowers in the financial market. Regulatory response to the Nigerian crisis closely mirrored the international response with increased capital and liquidity thresholds for commercial banks. While the rise of consumer protection on the agenda of prudential supervisors internationally was logical in that consumer debt was the main cause of the global recession, the Nigerian banking reforms of 2009 disproportionately affected access by poorer consumers, who ironically had little to do with the underlying causes of the crisis. As lending criteria become more stringent, poorer consumers of credit products are pushed into informal markets because of liquidity-induced credit rationing. Overall, consumer protection is compromised because stronger consumer protection rules for the formal sector benefits borrowers from formal institutions who constitute the minority of borrowers in all markets. While the passage of regulation establishing credit bureaux and the National Collateral Registry will, in theory, ease access to credit especially by lower-end borrowers, the vast size of the informal market continues to compound the information asymmetry problem, fiscal policies to tackle structural economic issues such as unemployment and illiteracy remain to be initiated, and bank regulators continue to pander to elite customers with policy responses that endorse too big to fail but deems lower-end consumers too irrelevant to save. The essay concluded that addressing the wide disparity in access to credit between the rich and poor through property rights reforms to capture the capital of the informal class, promoting regulation to check loan concentration, and stimulating competition by allowing Telecommunication Companies (TELCOs) and fintech companies to carry on lending activities because of their superior knowledge of lower-end markets will facilitate greater access. The risk of systemic failure deriving from consumer credit in Nigeria is insignificant compared to the consumer vulnerabilities resulting from the exposure of consumers to unregulated products in the informal market

Nanochitosan derived from marine bacteria

Nanochitosans are polysaccharides produced by the alkalescent deacetylation of chitin and comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. These are naturally formed from the deacetylation of shellfish shells and the exoskeleton of aquatic arthropods and crustaceans. Reports of chitosan production from unicellular marine bacteria inhabiting the sea, and possessing distinct animal- and plant-like characteristics abound. This capacity to synthesize chitosan from chitin arises from response to stress under extreme environmental conditions, as a means of survival. Consequently, the microencapsulation of these nanocarriers results in new and improved chitosan nanoparticles, nanochitosan. This nontoxic bioactive material which can serve as an antibacterial agent, gene delivery vector as well as carrier for protein and drug release as compared with chitosan, is limited by its nonspecific molecular weight and higher composition of deacetylated chitin. This chapter highlights the biology and diversity of nanochitosan-producing marine bacteria, including the factors influencing their activities, survival, and distribution. More so, the applications of marine bacterial nanochitosans in transfection and gene delivery; wound healing and drug delivery; feed supplement development and antimicrobial activity are discussed

Chapter 31 - Application of nanochitosan in tagging and nano-barcoding of aquatic and animal meats

Nanochitosans obtained from crustacean shells are biodegradable and biocompatible offering valuable functional, nutritional, and binding properties. Their low toxicity favors diverse industrial applications in various research models and can enable their use in the tagging of commercially sold aquatic and animal meat, easily contaminated by microbial sources during packaging, storage, and transportation. In this capacity, nanochitosans have been applied in fingerprinting for tracking and identifying the manufacturing and expiry dates of commercially sold meats and fish, as well as delivery of antioxidants and antimicrobials in these food products without affecting product consistency, composition, and organoleptic property. This chapter reviews current research on chitosan-based nanoparticles as barcodes and biosensors in tagging and monitoring aquatic and animal meats; and highlights methods of fish tagging and coding, and the benefits as well as the properties of materials used as biosensors in nano-barcoding of fish and meat

Effects of urban green infrastructure (UGI) on local outdoor microclimate during the growing season

This study analyzed how the variations of plant area index (PAI) and weather conditions alter the influence of urban green infrastructure (UGI) on microclimate. To observe how diverse UGIs affect the ambient microclimate through the seasons, microclimatic data were measured during the growing season at five sites in a local urban area in The Netherlands. Site A was located in an open space; sites B, C, and D were covered by different types and configurations of green infrastructure (grove, a single deciduous tree, and street trees, respectively); and site E was adjacent to buildings to study the effects of their façades on microclimate. Hemispherical photography and globe thermometers were used to quantify PAI and thermal comfort at both shaded and unshaded locations. The results showed that groves with high tree density (site B) have the strongest effect on microclimate conditions. Monthly variations in the differences of mean radiant temperature (∆Tmrt) between shaded and unshaded areas followed the same pattern as the PAI. Linear regression showed a significant positive correlation between PAI and ∆Tmrt. The difference of daily average air temperature (∆Ta) between shaded and unshaded areas was also positively correlated to PAI, but with a slope coefficient below the measurement accuracy (±0.5 °C). This study showed that weather conditions can significantly impact the effectiveness of UGI in regulating microclimate. The results of this study can support the development of appropriate UGI measures to enhance thermal comfort in urban areas

Nanochitosan derived from marine bacteria

Nanochitosans are polysaccharides produced by the alkalescent deacetylation of chitin and comprise a series of 2‐deoxy‐2 (acetylamino) glucose linked by ß‐(1‐4) glycosidic linkages. These are naturally formed from the deacetylation of shellfish shells and the exoskeleton of aquatic arthropods and crustaceans. Reports of chitosan production from unicellular marine bacteria inhabiting the sea, and possessing distinct animal‐ and plant‐like characteristics abound. This capacity to synthesize chitosan from chitin arises from response to stress under extreme environmental conditions, as a means of survival. Consequently, the microencapsulation of these nanocarriers results in new and improved chitosan nanoparticles, nanochitosan. This nontoxic bioactive material which can serve as an antibacterial agent, gene delivery vector as well as carrier for protein and drug release as compared with chitosan, is limited by its nonspecific molecular weight and higher composition of deacetylated chitin. This chapter highlights the biology and diversity of nanochitosan‐producing marine bacteria, including the factors influencing their activities, survival, and distribution. More so, the applications of marine bacterial nanochitosans in transfection and gene delivery; wound healing and drug delivery; feed supplement development and antimicrobial activity are discussed

Utilization of nanochitosan for enzyme immobilization of aquatic and animal-based food packages

Studies have identified the properties of enzymes, functionalized molecules, and compounds in food industry applications as edible coatings and encapsulations, that assure prolonged food quality and standards. These molecules present benefits of longer shelf-life by delayed deterioration and inhibition of the proliferation of spoilage and mycotoxigenic microorganisms. However, challenges of reduced nutrient levels, miniaturized size, and low chemical stability remain concerning. Chitosan polymers naturally formed from the deacetylation of shellfish shells and exoskeletons of aquatic arthropods and crustaceans offer improved benefits when functionalized into nanoparticles as nanochitosans. These polysaccharides produced by the alkalescent deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. This chapter considers the health impacts and

Utilization of nanochitosan in the sterilization of ponds and water treatment for aquaculture

Water pollution constitutes the leading cause of infant mortality, neonatal deformities, and shrinkage of man’s average life expectancy. Pollutants come from point and nonpoint sources; and water pollution arises from the discharge of wastewater containing undesirable impurities used for domestic, agricultural, and industrial purposes. More so, high nutrient and wastewater runoffs from fish production systems contribute to the fouling and eutrophication of recipient water bodies. Hence, aquaculture which is inextricably linked to the natural environment is challenged by the dearth of appropriate water quantity and quality, militating against fish, and fishery production. Nanochitosans as polysaccharides produced by the alkalescent deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. They are naturally formed from the deacetylation of shellfish shells and exoskeletons of aquatic arthropods and crustaceans. The unique attributes of chitin confer a wide range of biotechnological applications on the polymer, observed in flocculation as a wastewater treatment and purification route initiated by chitosan. This chapter highlights nanochitosan properties of aquaculture relevance; and elucidates the purification potentials of nanochitosan, compared to inorganic coagulants and organic polymeric flocculants. Effects of chitosan on contaminants and microorganisms, as well as applications in fish pathogens detection, fish disease diagnosis, and control are discussed