Strength and Environmental Performance Evaluation of Weathered Hydrocarbon Contaminated Soil Treated with Modified Plantain Peels-A Low Carbon Remediation Solution.

This study investigated the structural and environmental recovery of weathered hydrocarbon-contaminated soils using low-carbon solutions and aimed to ascertain the suitability of the remediated soils for engineering purposes. 25% (/) of ground ripe (RPP) and unripe (UPP) waste plantain peels were each added to 1 kg weathered hydrocarbon-contaminated soil samples and monitored for 90 days. Biological, physicochemical, and engineering properties were analysed for all samples in triplicates.

Wet-Dry Cycles and Microstructural Characteristics of Expansive Subgrade Treated with Sustainable Cementitious Waste Materials.

This work presents an experimental study on the physico-mechanical and microstructural characteristics of stabilised soils and the effect of wetting and drying cycles on their durability as road subgrade materials. The durability of expansive road subgrade with a high plasticity index treated with different ratios of ground granulated blast furnace slag (GGBS) and brick dust waste (BDW) was investigated. Treated and cured samples of the expansive subgrade were subjected to wetting-drying cycles, California bearing ratio (CBR) tests, and microstructural analysis.

Behaviour and Microstructural Characteristics of Lime-GGBS-Treated Kaolin Clay Contaminated with Gypsum.

In this experimental study, the physico-mechanical and microstructural properties of sulphate-bearing clays have been investigated. Sulphate bearing soils constituted by mixing kaolin and gypsum at 0%, 15%, 25%, and 35% gypsum contents were treated with 12% ordinary Portland cement (OPC) and 4%Lime (L) and 8% ground granulated blast furnace slag (GGBS) and subjected to compaction, swell, unconfined compressive strength (UCS), California bearing ratio (CBR), and scanning electron microscopy (SEM) and energy dispersive spectrometry (EDX) analyses. The results of the study showed that the use of L-GGBS improved the soaked CBRs of the treated samples by over 43% when compared to OPC-treated samples after 7-days curing.

Optimisation of Embodied Carbon and Compressive Strength in Low Carbon Concrete.

To improve the prediction of compressive strength and embodied carbon of low carbon concrete using a program algorithm developed in MATLAB, 84 datasets of concrete mix raw materials were used. The influence of water, silica fume and ground granular base slag was found to have a significant impact on the extent of low carbon concrete behaviour in terms of compressive strength and embodied carbon. While the concrete compressive strength for normal concrete increases with reducing water content, it is observed that the low carbon concrete using lightweight aggregate material increases in compressive strength with an increase in embodied carbon.

Criteria for Preliminary Risk Assessment of Brownfield Site: An International Survey of Experts.

Comprehensive risk assessment of brownfield sites requires a broad range of knowledge and multi-disciplinary expertise. Whilst the identification of criteria requirements for preliminary risk assessment has received some attention, there appears to be no studies that have specifically examined professional perspectives relating to these requirements. Yet, variations in professional practitioners' assessments may have significant consequences for the assessment of risks, and how the criteria are imparted to stakeholders.

Strength Predictive Modelling of Soils Treated with Calcium-Based Additives Blended with Eco-Friendly Pozzolans-A Machine Learning Approach.

The unconfined compressive strength (UCS) of a stabilised soil is a major mechanical parameter in understanding and developing geomechanical models, and it can be estimated directly by either lab testing of retrieved core samples or remoulded samples. However, due to the effort, high cost and time associated with these methods, there is a need to develop a new technique for predicting UCS values in real time. An artificial intelligence paradigm of machine learning (ML) using the gradient boosting (GB) technique is applied in this study to model the unconfined compressive strength of soils stabilised by cementitious additive-enriched agro-based pozzolans.

Road Pavement Thickness and Construction Depth Optimization Using Treated and Untreated Artificially-Synthesized Expansive Road Subgrade Materials with Varying Plasticity Index.

Road pavement thickness and their depth of construction take a chunk of the overall cost of road construction. This has called for a need for reduced road pavement thickness by improving the engineering properties of subgrade such as the California bearing ratio (CBR). The CBR of road subgrade has been a major determining factor for road pavement thickness, and expansive subgrades generally have a low CBR, resulting in major road defects.

Triquetrohamate Impaction Syndrome: An Unrecognized Cause of Ulnar-Sided Wrist Pain; Its Presentation Further Defined.

Background: The aim of this review was to further define the clinical condition triquetrohamate (TH) impaction syndrome (THIS), an entity underreported and missed often. Its presentation, physical findings, and treatment are presented.

Methods: Between 2009 and 2014, 18 patients were diagnosed with THIS.

Analysis of the jugular foramen in pediatric patients with craniosynostosis.

Introduction: Intracranial hypertension due to craniosynostosis is a dreaded potential complication that affects the developing brain. We hypothesized that craniosynostotic patients have significantly reduced jugular foramen (JF) when compared with age-matched controls. This may partially account for the observed increase in intracranial pressure (ICP) seen in some of these patients.

Effect of ethanol on the gelation of aqueous solutions of Pluronic F127.

In dilute aqueous solution unimers of copolymer F127 (E(98)P(67)E(98)) associate to form micelles, and in more concentrated solution micelles pack to form high-modulus gels. Cosolvents are known to affect these processes, and ethanol/water mixtures have been of particular interest. Dynamic light scattering from dilute solutions was used to confirm micellization, but major attention was directed towards the gels.

Aqueous gels of mixtures of ionic surfactant SDS with pluronic copolymers P123 or F127.

Gel diagrams based on tube inversion and oscillatory rheometry are reported for Pluronic copolymers F127 (E(98)P(67)E(98)) and P123 (E(21)P(67)E(21)) in mixtures with anionic surfactant sodium dodecyl sulfate (SDS). Total concentrations (c, SDS+copolymer) were as high as 50 wt % with mole ratios SDS/copolymer (mr) in the ranges 1-5 (F127) and 1-7 (P123). Temperatures were as high as 90 degrees C.

Solubilisation of griseofulvin, quercetin and rutin in micellar formulations of triblock copolymers E62P39E62 and E137S18E137.

The solubilisation of two poorly soluble flavonoids, quercetin and rutin, in micellar solutions of mixtures of a block copolymer of ethylene oxide and styrene oxide (E(137)S(18)E(137)) with one of ethylene oxide and propylene oxide (E(62)P(39)E(62)) has been studied at 25 and 37 degrees C. Solubilisation capacities were higher than those for the model poorly water-soluble drug griseofulvin and comparable with published values for the solubilisation of rutin by beta-cyclodextrin.

Solubilisation of griseofulvin in aqueous micellar solutions of diblock copolymers of ethylene oxide and 1,2-butylene oxide with lengthy B-blocks.

The influence of hydrophobic-block length on solubilisation capacity was examined for micelles of E(m)B(n) copolymers (E=oxyethylene, B=oxybutylene, subscripts denote number-average block lengths in repeat units) with B-block lengths in the range of 30-76 and with E-blocks of sufficient length to ensure the formation of spherical micelles. Griseofulvin was used as a model poorly-water-soluble drug known to be almost exclusively solubilised in the micellar core. Combination of solubilisation data with those of a previous study has shown that the amount of drug solubilised per gram of hydrophobe is essentially independent of B-block length when this exceeds about 15 B units, suggesting that core size is not a major influence on solubilisation.

Magneto-biomonitoring of intra-urban spatial variations of particulate matter using tree leaves.

Preliminary mineral magnetic results from a pilot project investigating the suitability of roadside tree leaves as depositories of vehicular pollution are presented. Tree leaf surfaces (Lime: Tilia europaea; Sycamore: Acer pseudoplatanus) at four roadside and one woodland location in Wolverhampton, UK, have been monitored (July 2003 to November 2003). Mineral magnetic technologies have revealed spatial variations of particulate pollution concentration throughout the conurbation and data analysis indicates that magnetic concentration parameters are suitable proxies for fine particulate pollution, which are particularly hazardous to health.

Effect of ethanol on the micellization and gelation of pluronic p123.

In certain applications copolymer P123 (E21P67E21) is dissolved in water-ethanol mixtures, initially to form micellar solutions and eventually to gel. For P123 in 10, 20, and 30 wt % aqueous ethanol we used dynamic light scattering from dilute solutions to confirm micellization, oscillatory rheometry, and visual observation of mobility (tube inversion) to determine gel formation in concentrated solutions and small-angle X-ray scattering (SAXS) to determine gel structure. Except for solutions in 30 wt % aqueous ethanol, a clear-turbid transition was encountered on heating dilute and concentrated micellar solutions alike, and as for solutions in water alone (Chaibundit et al.

Medical waste management in Ibadan, Nigeria: obstacles and prospects.

Quantification and characterization of medical waste generated in healthcare facilities (HCFs) in a developing African nation has been conducted to provide insights into existing waste collection and disposal approaches, so as to provide sustainable avenues for institutional policy improvement. The study, in Ibadan city, Nigeria, entailed a representative classification of nearly 400 healthcare facilities, from 11 local government areas (LGA) of Ibadan, into tertiary, secondary, primary, and diagnostic HCFs, of which, 52 HCFs were strategically selected. Primary data sources included field measurements, waste sampling and analysis and a questionnaire, while secondary information sources included public and private records from hospitals and government ministries.

Diblock copolymers of ethylene oxide and 1,2-butylene oxide in aqueous solution: formation of unimolecular micelles.

The dependence of log(cmc) on hydrophobic block length n was examined for E(m)B(n) copolymers (E=oxyethylene, B=oxybutylene, subscripts denote number-average block lengths in repeat units) with n in the range 30-76. Combination with published data for E(m)B(n) diblock copolymers with shorter E-blocks shows two changes of slope in the log(cmc)-n plot corresponding to the onset of unimolecular micelle formation at n approximately 12 and completion of this process at n approximately 30. The results are discussed with reference to published data for E(m)L(n) and E(m)CL(n) (L from d,L-lactide; CL from epsilon-caprolactone) copolymers, which show similar behaviour.

Solubilisation of drugs in micellar solutions of diblock copolymers of ethylene oxide and styrene oxide.

The solubilisation of two poorly soluble drugs, furosemide and nabumetone, in micellar solutions of diblock copolymers of ethylene oxide and styrene oxide has been studied at 25 and 37 degrees C and solubilisation capacities compared with published values for griseofulvin and docetaxel. Solubilisation in the micelle core, corrected for the different proportions of poly(styrene oxide) in the copolymers, was similar for all four drugs. The highest solubilisation capacities were found for a copolymer with worm-like micelles.

Solubilisation of drugs in worm-like micelles of block copolymers of ethylene oxide and 1,2-butylene oxide in aqueous solution.

Ethylene oxide and 1,2-butylene oxide were sequentially polymerised to form the diblock copolymer E13B10 (E=oxyethylene, B=oxybutylene, subscripts denote number-average block lengths in repeat units). Dynamic and static light scattering over the temperature range 10-30 degrees C demonstrated a transition from compact (spheroidal) micelles to larger, more elongated (worm-like) micelles with temperature increase above a critical onset temperature of about 20 degrees C. Determination of the solubilisation capacity for griseofulvin, carbamazepine and spironolactone of dilute micellar solutions of this copolymer, together with those of E11B8 and E17B12 block copolymers (which also show the sphere-to-worm transition), allowed investigation of the influence on solubilisation characteristics of hydrophobic block length and temperature.

Poly(ethylene oxide) based copolymers: solubilisation capacity and gelation.

It is thought that almost half of potentially useful drug candidates fail to progress to formulation development because of their low aqueous solubility and associated poor or erratic absorption characteristics. A response to this challenge has been the development of a variety of colloidal delivery systems in which the therapeutic agent is encapsulated in nanosized particles. In this review, attention is focussed on colloidal vectors based on amphiphilic block copolymers, the micelles of which can accommodate a wide range of water-insoluble guest molecules, and particularly on copolymers with poly(oxyethylene) as the hydrophilic block and with poly(oxyalkylene) or polyester hydrophobic blocks, taking advantage of the 'stealth' properties of the poly(oxyethylene) corona of their micelles.

Block copolymers for drug solubilisation: relative hydrophobicities of polyether and polyester micelle-core-forming blocks.

Published values of the critical micelle concentration are tabulated for diblock copolymers E(m)P(n), E(m)B(n), E(m)S(n), E(m)L(n), E(m)VL(n) and E(m)CL(n), where E denotes a chain unit derived from ethylene oxide, P from propylene oxide, B from 1,2-butylene oxide, S from styrene oxide, L from dl-lactide, VL from gamma-valerolactone and CL from epsilon-caprolactone, and the subscripts denote average chain lengths. Noting that log(cmc/moldm(-3) is proportional to the standard Gibbs energy of micellisation, the dependence of this quantity on hydrophobic block length (n) is explored for a given E-block length. Superposition of data allows ranking of the hydrophobicities of the chain units.

Micellization and gelation of mixed copolymers P123 and F127 in aqueous solution.

The micellization in dilute aqueous solution of Pluronic copolymers P123 (E21P67E21) and F127 (E98P67E98) and mixtures of the two was investigated using static and dynamic light scattering. Gelation of concentrated solutions of the two copolymers and their mixtures was studied using tube inversion and oscillatory rheometry. The two copolymers comicellized to give micelles with narrow size distributions.

Mixtures of triblock copolymers E(62)P(39)E(62) and E(137)S(18)E(137) potential for drug delivery from in situ gelling micellar formulations.

The gelation behaviour of concentrated micellar solutions of mixtures of a block copolymer of ethylene oxide and styrene oxide (E(137)S(18)E(137)) with one of ethylene oxide and propylene oxide (E(62)P(39)E(62)) has been investigated. Over a wide range of compositions, up to 90 wt.% E(137)S(18)E(137) in the mixture, gelation resembled that of solutions of E(62)P(39)E(62) alone, i.

Micellization and drug solubilization in aqueous solutions of a diblock copolymer of ethylene oxide and phenyl glycidyl ether.

The aim of this study was to define a block copolymer micellar system with a high solubilization capacity for poorly soluble aromatic drugs. Ethylene oxide and phenyl glycidyl ether were sequentially polymerized to form the diblock copolymer G5E67 (G = phenyl glycidyl ether, OCH2CH(CH2OC6H5); E = oxyethylene, OCH2CH2; subscripts denote number-average block lengths in repeat units). The association properties in aqueous solution over the range 20-50 degrees C were investigated by surface tensiometry and light scattering, yielding values of the cmc, hydrodynamic radius, and association number; gel boundaries in concentrated micellar solution were investigated by tube inversion.

Self-association of block copoly(oxyalkylene)s in aqueous solution. Effects of composition, block length and block architecture.

The article deals with the association behaviour in dilute aqueous solution of block copoly(oxyalkylene)s in which hydrophilic poly(ethylene oxide) is combined with hydrophobic poly(propylene oxide), poly(1,2-butylene oxide) or poly(styrene oxide). Polymers with three simple architectures are considered, i.e.