•Insurgencies are shaped by structural conditions of possibility.•The Nigeria insurgency is shaped by the expulsion of young men from institutions of authority.•The ordering of power within Nigeria’s ...petro-state engendered frontiers.•Frontiers emerge in a crisis of social reproduction and changing capabilities of the state.•The frontier is a social space where legitimate power and authority are objects of deep contention.
The focus of this article is two home-grown insurgencies which arose in Nigeria after the return to civilian rule in 1999: Boko Haram in the Muslim northeast, the Movement for the Emancipation of the Niger Delta (MEND) in the oil producing and Christian southeast. The two insurgencies arose, I argue, from frontier spaces in which the limits of state authority and legitimacy intersected with a profound crisis of authority and rule on the one hand, and the political economy of radical precarity on the other. Boko Haram and MEND share family resemblances—they are products of the same orderings of power—despite the obvious fact that one is draped in the language of religion and restoration (but as we shall see modernity) and the insistence that Nigeria should become transformed into a true Islamic state, while the other is secular and civic (and also modern) wishing to expand the boundaries of citizenship through a new sort of federalism. There are striking commonalities in the social composition of the armed groups and their internal dynamics; each is deposited at the nexus of the failure of local government, customary institutions, and the security forces (the police and the military task forces in particular). Each, nevertheless, is site specific; a cultural articulation of dispossession politics rooted in regional traditions of warfare, in particular systems of religiosity, and very different sorts of social structure and identity, and very different ecologies (the semi arid savannas of the north, and the creeks and forest of the Niger delta). In both cases state coercion and despotism and the ethico-moral decrepitude of the state figures centrally as does the politics of resentment that each condition generates among a large, alienated but geographically rooted group of precarious classes.
Elevated lipoprotein(a) Lp(a) is independently associated with increased cardiovascular risk. However, treatment options for elevated Lp(a) are limited. Alirocumab, a monoclonal antibody to ...proprotein convertase subtilisin/kexin type 9, reduced low-density lipoprotein cholesterol (LDL-C) by up to 62% from baseline in phase 3 studies, with adverse event rates similar between alirocumab and controls. We evaluated the effect of alirocumab on serum Lp(a) using pooled data from the phase 3 ODYSSEY program: 4,915 patients with hypercholesterolemia from 10 phase 3 studies were included. Eight studies evaluated alirocumab 75 mg every 2 weeks (Q2W), with possible increase to 150 mg Q2W at week 12 depending on LDL-C at week 8 (75/150 mg Q2W); the other 2 studies evaluated alirocumab 150-mg Q2W from the outset. Comparators were placebo or ezetimibe. Eight studies were conducted on a background of statins, and 2 studies were carried out with no statins. Alirocumab was associated with significant reductions in Lp(a), regardless of starting dose and use of concomitant statins. At week 24, reductions from baseline were 23% to 27% with alirocumab 75/150-mg Q2W and 29% with alirocumab 150-mg Q2W (all comparisons p <0.0001 vs controls). Reductions were sustained over 78 to 104 weeks. Lp(a) reductions with alirocumab were independent of race, gender, presence of familial hypercholesterolemia, baseline Lp(a), and LDL-C concentrations, or use of statins. In conclusion, in addition to marked reduction in LDL-C, alirocumab leads to a significant and sustained lowering of Lp(a).
The frequency and duration of flooding events is increasing due to land-use changes increasing run-off of precipitation, and climate change causing more intense rainfall events. Floodplain soils ...situated downstream of urban or industrial catchments, which were traditionally considered a sink of potentially toxic elements (PTEs) arriving from the river reach, may now become a source of legacy pollution to the surrounding environment, if PTEs are mobilised by unprecedented flooding events.
When a soil floods, the mobility of PTEs can increase or decrease due to the net effect of five key processes; (i) the soil redox potential decreases which can directly alter the speciation, and hence mobility, of redox sensitive PTEs (e.g. Cr, As), (ii) pH increases which usually decreases the mobility of metal cations (e.g. Cd2+, Cu2+, Ni2+, Pb2+, Zn2+), (iii) dissolved organic matter (DOM) increases, which chelates and mobilises PTEs, (iv) Fe and Mn hydroxides undergo reductive dissolution, releasing adsorbed and co-precipitated PTEs, and (v) sulphate is reduced and PTEs are immobilised due to precipitation of metal sulphides. These factors may be independent mechanisms, but they interact with one another to affect the mobility of PTEs, meaning the effect of flooding on PTE mobility is not easy to predict. Many of the processes involved in mobilising PTEs are microbially mediated, temperature dependent and the kinetics are poorly understood.
Soil mineralogy and texture are properties that change spatially and will affect how the mobility of PTEs in a specific soil may be impacted by flooding. As a result, knowledge based on one river catchment may not be particularly useful for predicting the impacts of flooding at another site. This review provides a critical discussion of the mechanisms controlling the mobility of PTEs in floodplain soils. It summarises current understanding, identifies limitations to existing knowledge, and highlights requirements for further research.
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•Floodplains may switch from being sinks to becoming sources of legacy pollution.•Flooding influences pH, DOM and the mobility of potentially toxic elements (PTEs).•Reductive dissolution of Fe and Mn oxides mobilises PTEs.•Precipitation of metal sulphides reduces PTE mobility.•Field observations are required to further advance our understanding.
Globally, more than 800 million people are undernourished while >2 billion people have one or more chronic micronutrient deficiencies (MNDs). More than 6% of global mortality and morbidity burdens ...are associated with undernourishment and MNDs. Here we show that, in 2011, 3.5 and 1.1 billion people were at risk of calcium (Ca) and zinc (Zn) deficiency respectively due to inadequate dietary supply. The global mean dietary supply of Ca and Zn in 2011 was 684 ± 211 and 16 ± 3 mg capita(-1) d(-1) (± SD) respectively. Between 1992 and 2011, global risk of deficiency of Ca and Zn decreased from 76 to 51%, and 22 to 16%, respectively. Approximately 90% of those at risk of Ca and Zn deficiency in 2011 were in Africa and Asia. To our knowledge, these are the first global estimates of dietary Ca deficiency risks based on food supply. We conclude that continuing to reduce Ca and Zn deficiency risks through dietary diversification and food and agricultural interventions including fortification, crop breeding and use of micronutrient fertilisers will remain a significant challenge.
The photodegradation of chlorine-based disinfectants NH
2Cl, HOCl, and OCl
− under UV irradiation from low- (LP) and medium-pressure (MP) Hg lamps was studied. The quantum yields of aqueous chlorine ...and chloramine under 254
nm (LP UV) irradiation were greater than 1.2
mol
Es
−1 for free chlorine in the pH range of 4–10 and 0.4
mol
Es
−1 for monochloramine at pH 9. Quantum yields for MP (200–350
nm) ranged from 1.2 to 1.7
mol
Es
−1 at neutral and basic pH to 3.7
mol
Es
−1 at pH 4 for free chlorine, and 0.8
mol
Es
−1 for monochloramine. Degradation of free chlorine was enhanced under acidic water conditions, but water quality negatively impacted the MP Hg lamp degradation of free chlorine, compared to the LP UV source. The production of hydroxyl radical via chlorine photolysis was assessed along with the rate of reaction between
OH and HOCl using radical scavengers (parachlorobenzoic acid and nitrobenzene) in chlorinated solutions at pH 4. The quantum yield of OH radical production from HOCl at 254
nm was found to be 1.4
mol
Es
−1, while the reaction of HOCl with OH radical was measured as 8.5×10
4
M
−1
s
−1. NH
2Cl was relatively stable in all irradiated solutions, with <0.3
mg
L
−1 increase in nitrate following a UV dose of 1000
mJ
cm
−2. For water treatment plants, no significant changes in chlorine concentration would be expected under typical pH levels and UV doses; however, the formation of
OH could have implications for chlorinated byproducts or decay of unwanted chemical contaminants.
Monoclonal antibodies have therapeutic potential for treating diseases of the central nervous system, but their accumulation in the brain is limited by the blood-brain barrier (BBB). Here, we show ...that reducing the affinity of an antibody for the transferrin receptor (TfR) enhances receptor-mediated transcytosis of the anti-TfR antibody across the BBB into the mouse brain where it reaches therapeutically relevant concentrations. Anti-TfR antibodies that bind with high affinity to TfR remain associated with the BBB, whereas lower-affinity anti-TfR antibody variants are released from the BBB into the brain and show a broad distribution 24 hours after dosing. We designed a bispecific antibody that binds with low affinity to TfR and with high affinity to the enzyme β-secretase (BACE1), which processes amyloid precursor protein into amyloid-β (Aβ) peptides including those associated with Alzheimer's disease. Compared to monospecific anti-BACE1 antibody, the bispecific antibody accumulated in the mouse brain and led to a greater reduction in brain Aβ after a single systemic dose. TfR-facilitated transcytosis of this bispecific antibody across the BBB may enhance its potency as an anti-BACE1 therapy for treating Alzheimer's disease.
This study examined the status of toxic metal contamination of the urban industrial city of Ahvaz in Iran. Two hundred and twenty-seven surface soils from a depth horizon of 0-10 cm were collected ...from urban areas. In addition, 15 soil samples were collected to recognise the sources of Pb in urban topsoils in Ahvaz city. Mean concentration of Pb, Zn, Cu and As were 181 ± 167, 123 ± 118, 185 ± 167 and 6.9 ± 8.9 mg.kg
, respectively. Results of inter-element relationship among studied toxic metals revealed that Pb, Zn and Cu may have the same anthropogenic origin, whilst As originated from different sources. The results of pollution index (PI) and Nemerow pollution index (NPI) implied that Pb, Zn, and Cu had a moderate to high level of pollution. The Pb isotopic composition analysis suggested clear anthropogenic origins of Pb including industrial emission, vehicle exhaust and dust storm with the mean contributions of 47%, 15% and 7%, respectively, by a four-end member model.
Increasing zinc (Zn) concentrations in crops is important for alleviation of human Zn deficiency. Arbuscular mycorrhizal fungi (AMF) contribute to plant Zn uptake, but their contribution to Zn in the ...edible portion of crops has not yet been investigated. This study aimed to quantify the mycorrhizal pathway of Zn uptake into grain of wheat and barley under varying soil Zn availabilities. Bread wheat (Triticum aestivum) and barley (Hordeum vulgare) were grown in pots with a hyphal compartment containing
Zn. Plants were inoculated with Rhizophagus irregularis and grown at three soil Zn concentrations. Radioactive Zn in grain and straw was measured and the contribution of AMF to Zn uptake was calculated.
The mycorrhizal pathway of Zn uptake contributed up to 24.3% of total above-ground Zn in wheat, and up to 12.7% of that Zn in barley. The greatest contribution by the mycorrhizal pathway was observed in barley at the lowest Zn addition, and in wheat at the highest one. In addition, grain yield of bread wheat was increased by AMF.
These results suggest that AMF have a substantial role in uptake of Zn into cereals, and the proportional contribution by the MPU is dependent on plant species, as well as available soil Zn.
•A comprehensive review of chromium speciation in foodstuffs is presented in this article.•Cr(VI) concentrations from off-line extraction and analytical techniques should be questioned.•Isotope ...dilution techniques can monitor species interconversions during extraction.•New speciation techniques should also focus on the measurement of Cr(III).
Numerous critical reviews have evaluated exposure to toxic and carcinogenic hexavalent chromium (Cr(VI)) from a number of pathways; including workplace air, cement and packaging materials. The contribution of foodstuffs to dietary Cr(VI) has been increasingly under investigation, however no summary of this work has been carried out. The objective of this article is to review the last twenty years of chromium speciation research in foodstuffs. Alkaline extraction, used for chromium speciation in other solids, is the most widely-reported procedure. Previous measurement of Cr(VI) in foodstuffs is questionable due to the reducing power of organic matter and antioxidants, leading to the development of speciated isotope dilution mass spectrometry (SIDMS) techniques to monitor interconversions. Evaluation of the genotoxicity of trivalent chromium (Cr(III)), which acts through a different pathway to that of Cr(VI), requires reconsideration towards measurement of Cr(III), which is present at higher concentrations in foodstuffs following reduction of the more-bioavailable Cr(VI).
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