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The understanding of the factors influencing the active interaction and coalescence of intrarift fault segments in extending continental regions is limited. The 2009 Mw6.0 Karonga earthquake occurred in the westernmost portion of the Northern Malawi Rift, which hosts clustered intrarift faulting. The event ruptured the strongly coalesced southern segment of the St. Mary Fault (sSMF), and subsequently, moderate-magnitude events localized on poorly -coalesced segments that define the northern continuation of the fault. To investigate the role of coseismic stress redistribution on interacting faults, we explore the slip distribution of the 2009 event with realistic 3D strike-variable fault geometries, and compute coseismic Coulomb stress changes around the sSMF and neighboring faults. The results suggest that the down-dip intersections of the sSMF with the neighboring faults partition strain in a way that directs most of the deformation to >5 km depths. Additionally, the coseismic stress changes from the 2009 earthquake promoted interactions between the sSMF and adjoining northern segments of the fault at shallow (<5 km) depths, indicating that upper-crustal hard-linkage is underway in the poorly coalesced en-echelon sections of the northern segment. These results demonstrate how coseismic static stress transfer between evolving intrarift fault systems drive fault linkage over a single seismic cycle. Over successive slip events, such stress transfer processes may accelerate the linkage and coalescence of contiguous intrarift fault segments, amalgamate and deepen sub-basins along-strike, and promote across-rift basin compartmentalization. This process is relevant for fault coalescence over multi-seismic cycles, progressive maturation of rift basins, and transitions from juvenile continental rifting to the development of margins where break-up can initialize. • Fault interactions during the 2009 Mw6.0 earthquake in Malawi vertically partition strain. • The coseismic stress changes directed most of the deformation to >5 km depths. • Northward interaction between the source fault and its segments occurs at depths <5 km. • The tress transfer accelerates the linkage of contiguous intrarift fault segments. • This process is relevant for the progressive maturation of rift basins. [ABSTRACT FROM AUTHOR]

In cratonic interiors, long-lived brittle shear zones host records of polyphase deformation, representing inherited structures that can host damaging earthquakes. Here, we explore the internal structure of the Kgomodikae Shear Zone (KSZ), signifying the western continuation of the ∼800-km long Precambrian Kgomodikae-Thabazimbi-Murchinson Fault System which extend along a region of widespread seismicity in southern Africa. At satellite-scale, the KSZ exhibits ENE-to-NE-striking subparallel zones of alternating high/low lineament clustering intensities, with peak-intensity zones that represent hydrologically-permeable principal brittle shear bands. In outcrops, we find pervasive occurrence of slip surfaces with dominant strike-slip paleo-slip vectors, and silica-cemented fault rocks hosting collocated quartz and pseudotachylyte vein clusters. Ground-based scanline fracture mapping reveals peak damage intensity in proximity of the satellite-mapped lineaments (localized high strain zones?), but with the pseudotachylytes occurring in both the peak- and flanking lower-intensity damage zones. The results suggest that the KSZ hosted paleoseismic ruptures that were not confined to its principal slip zones but may have nucleated on- or ruptured into off-fault splays; and that the NW-striking splays have greater reactivation tendency in contemporary stress field. In general, our findings highlight the nature of preexisting off-fault damage networks that accommodated earthquake rupture and propagation patterns in intraplate regions. • We quantify damage distribution across the intracratonic Kgomodikae Shear Zone (KSZ). • At satellite-scale, sub-parallel vegetation lineaments in the KSZ follow localized damage. • Outcrops host pervasive silicified slip surfaces with cemented breccia and pseudotachylytes. • The pseudotachylytes occur in both the high-fracture intensity shear bands and their flanks. • Paleoseismic events were not confined to the principal slip zones, but exploited off-fault splays. [ABSTRACT FROM AUTHOR]

Electronic waste (e-waste) dismantling and dumpsite processes are major sources of organophosphate flame retardant and plasticiser emissions and may pose potentially adverse effects on environment and human health. In 20 outdoor dust and 49 soil samples collected from four e-waste dismantling and three e-waste dumpsites in two States of Nigeria (Lagos and Ogun), we identified 13 alternative plasticisers (APs), 7 legacy phthalate plasticisers (LPs), and 17 organophosphorus flame retardants (OPFRs) for the first time in African e-waste streams. In the samples from dismantling sites, the range (median) concentrations of ∑ 13 APs, ∑ 7 LPs, and ∑ 17 OPFRs were 11–2747 μg/g (144 μg/g), 11–396 μg/g (125 μg/g), and 0.2–68 μg/g (5.5 μg), in dust respectively and 1.8–297 μg/g (55 μg/g), 1.3–274 μg/g (48.5 μg/g), and 1.6–62 μg/g (1.6 μg/g), in soil respectively. Results for soil samples from e-waste dumpsites were (6.6–195 μg/g (23.7 μg/g), 6.0–295 μg/g (54.8), and 0.4–42.3 μg/g (9.0 μg/g) for ∑ 13 APs, ∑ 7 LPs, and ∑ 17 OPFRs respectively. Overall, concentrations of APs were significantly higher at the dismantling sites (p = 0.005) compared to dumpsites, levels of LPs were higher at dismantling sites but not significant, while OPFR concentrations were significantly higher in dumpsite samples (p = 0.005). Plasticisers were found to be major contributors to pollution at e-waste dismantling sites, while OPFRs were associated with both automobile dismantling and e-waste dumpsite processes. Following particle size fractionation of selected soil samples, higher concentrations of targeted compounds were observed in the smaller mesh (180 μm) soil sieve fraction. For dust, the total median estimated daily intake via ingestion and dermal adsorption (EDI ing and EDI derm) ranged from 43 to 74 ng/kg bw/day and 0.4–0.7 ng/kg bw/day, respectively. Correspondingly, 4.6–45 ng/kg bw/day and 0.015–0.57 ng/kg bw/day were the values found for soil, respectively. According to these results, the targeted chemicals do not appear to pose a non-carcinogenic risk to e-waste workers through ingestion or dermal contact of bio-accessible fractions of the chemicals. Human biomonitoring campaigns are recommended in the Nigerian e-waste environment considering the elevated concentration levels found for the majority of targeted compounds and that risk parameters required for exposure assessment were only available for a limited number of compounds. [Display omitted] • Release of plasticisers to soil was mainly linked with dismantling processes. • Release of OPFRs was associated with e-waste dismantling and dumpsite activities. • Diisononyl phthalate was the most dominant plasticiser up to 2000 μg/g. • Resorcinol diphenyl phosphate had the highest level (54 μg/g) of all OPFRs. • Exposure to bio-accessible fractions of chemicals poses no non-carcinogenic risk. [ABSTRACT FROM AUTHOR]

A stable money demand function is essential when using monetary aggregate as a monetary policy. Thus, there is need to examine the stability of the money demand function in Nigeria after the deregulation of the financial sector. To achieve this, the study employed CUSUM (cumulative sum) and CUSUMSQ (CUSUM of square) tests after using autoregressive distributive lag bounds test to determine the existence of a long run relationship between monetary aggregates and their determinants. Results of the study show that a long-run relationship holds and that the demand for money is stable in Nigeria. In addition, the inflation rate is found to be a better proxy for an opportunity variable when compared to interest rate. The main implication of the study is that interest rate is ineffective as a monetary policy instrument in Nigeria. [ABSTRACT FROM AUTHOR]

• A dynamic scheduling framework for perfusion processes in a facility is presented. • Scheduling policies are adapted and proposed to react to failure and varying demand. • Policy parameters and process run times are tuned using evolutionary algorithms. • Tuned policies perform better than service level- or fixed cycle-based policies. • Novel policy with look-ahead heuristic is best especially with run times optimised. The biopharmaceutical industry is increasingly interested in moving from batch to semi-continuous manufacturing processes. These continuous bioprocesses are more failure-prone and process failure is more consequential. In addition, the probability of failure is dependent on process run time which generally is determined independent of scheduling considerations. This work presents a discrete-event simulation of continuous bioprocesses in a scheduling environment. Dynamic scheduling policies are investigated to make operational decisions in a multi-product manufacturing facility and react to process failure events and uncertain demand. First, different scheduling policies are adapted from the stochastic lot sizing literature and a novel look-ahead scheduling policy is proposed. Then, policy parameters (including process run time) are tuned using evolutionary algorithms. Our results demonstrate that the tuned policies perform much better than a policy that estimates policy parameters based on service level considerations and a policy based on a fixed cyclical sequence. [ABSTRACT FROM AUTHOR]