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In this contribution, we present "Birch‐type", and other reductions of simple arenes by the potassium salt of an anionic magnesium dinitrogen complex, [{K(TCHPNON)Mg}2(μ‐N2)] (TCHPNON=4,5‐bis(2,4,6‐tricyclohexylanilido)‐2,7‐diethyl‐9,9‐dimethyl‐xanthene), which acts as a masked dimagnesium(I) diradical in these reactions. This reagent is non‐hazardous, easy‐to‐handle, and in some cases provides access to 1,4‐cyclohexadiene reduction products under relatively mild reaction conditions. This system works effectively to reduce benzene, naphthalene and anthracene through magnesium‐bound "Birch‐type" reduction intermediates. Cyclohexadiene products can be subsequently released from the magnesium centres by protonolysis with methanol. In contrast, the reduction of substituted arenes is less selective and involves competing reaction pathways. For toluene and 1,3,5‐triphenylbenzene, the structural authentication of "Birch‐type" reduction intermediates is conclusive, although the formation of corresponding 1,4‐cyclohexadiene derivatives was low yielding. Reduction of anisole did not yield an isolable "Birch‐type" intermediate, but instead gave a C−O activation product. Treating triphenylphosphine with [{K(TCHPNON)Mg}2(μ‐N2)] resulted in the extrusion of both biphenyl and dinitrogen to afford a magnesium(II) phosphanide [{K(TCHPNON)Mg(μ‐PPh2)}2]. Reduction of fluorobenzene proceeded via C−F activation of the arene, and isolation of the magnesium(II) fluoride [{K(TCHPNON)Mg(μ‐F)}2]. Finally, the two‐electron reduction of 1,3,5,7‐cyclooctatetraene (COT) with [{K(TCHPNON)Mg}2(μ‐N2)] yielded a complex, [{K(TCHPNON)Mg}2(μ‐COT)], incorporating the aromatic dianion (COT2−). [ABSTRACT FROM AUTHOR]

Seven inscriptions from Oine on Ikaria that refer to Samians residing on the island have long been used to argue the case for Samian political control over Ikaria. This article seeks to reassess what these inscriptions tell us about Samian–Ikarian interactions by exploring different models of connectivity for the two islands. Specifically, this article considers short-range mobility, and the capacity of each island to perform various political functions. [ABSTRACT FROM AUTHOR]

Numerous industrial processes utilise gaseous chemical feedstocks to produce useful chemical products. Atmospheric and other small molecule gases, including anthropogenic waste products (e.g. carbon dioxide), can be viewed as sustainable building blocks to access value-added chemical commodities and materials. While transition metal complexes have been well documented in the reduction and transformation of these substrates, molecular complexes of the terrestrially abundant alkaline earth metals have also demonstrated promise with remarkable reactivity reported towards an array of industrially relevant gases over the past two decades. This review covers low oxidation state and hydrido group 2 complexes and their role in the reduction and transformation of a selection of important gaseous substrates towards value-added chemical products. [ABSTRACT FROM AUTHOR]

The bulky β‐diketiminate ligand frameworks [BDIDCHP]− and [BDIDipp/Ar]− (BDI=[HC{C(Me)2N‐Dipp/Ar}2]− (Dipp=2,6‐diisopropylphenyl (Dipp); Ar=2,6‐dicyclohexylphyenyl (DCHP) or 2,4,6‐tricyclohexylphyenyl (TCHP)) have been developed for the kinetic stabilisation of the first europium (II) hydride complexes, [(BDIDCHP)Eu(μ‐H)]2, [(BDIDipp/DCHP)Eu(μ‐H)]2 and [(BDIDipp/TCHP)Eu(μ‐H)]2, respectively. These complexes represent the first step beyond the current lanthanide(II) hydrides that are all based on ytterbium. Tuning the steric profile of β‐diketiminate ligands from a symmetrical to unsymmetrical disposition, enhanced solubility and stability in the solution–state. This provides the first opportunity to study the structure and bonding of these novel Eu(II) hydride complexes crystallographically, spectroscopically and computationally, with their preliminary reactivity investigated. [ABSTRACT FROM AUTHOR]

Reduction of the magnesium(II) diamide [Mg(TripNON)] (TripNON = 4,5-bis(2,4,6-triisopropylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) with 5% w/w K/KI leads to a good yield of a dianionic dimagnesium(I) species, as its potassium salt, [{K(TripNON)Mg}2]. An X-ray crystallographic analysis shows the molecule to contain a very long Mg–Mg bond (3.137(2) Å). The formation of [{K(TripNON)Mg}2] contrasts with a previously reported reduction of a magnesium(II) complex incorporating a bulkier diamide ligand, which instead afforded a magnesium–dinitrogen complex. In the current study, [{K(TripNON)Mg}2] has been shown to be a viable reagent for the reductive activation of CO, H2 and N2O. [ABSTRACT FROM AUTHOR]

A simple sequential addition protocol for the reductive coupling of ketones and aldehydes by a potassium aluminyl grants access to unsymmetrical pinacolate derivatives. Isolation of an aluminium ketyl complex presents evidence for the accessibility of radical species. Product release from the aluminium centre was achieved using an iodosilane, forming the disilylated 1,2‐diol and a neutral aluminium iodide, thereby demonstrating the steps required to generate a closed synthetic cycle for pinacol (cross) coupling at an aluminyl anion. [ABSTRACT FROM AUTHOR]

The reaction of 9‐diazo‐9H‐fluorene (fluN2) with the potassium aluminyl K[Al(NON)] ([NON]2−=[O(SiMe2NDipp)2]2−, Dipp=2,6‐iPr2C6H3) affords K[Al(NON)(κN1,N3‐{(fluN2)2})] (1). Structural analysis shows a near planar 1,4‐di(9H‐fluoren‐9‐ylidene)tetraazadiide ligand that chelates to the aluminium. The thermally induced elimination of dinitrogen from 1 affords the neutral aluminium ketimide complex, Al(NON)(N=flu)(THF) (2) and the 1,2‐di(9H‐fluoren‐9‐yl)diazene dianion as the potassium salt, [K2(THF)3][fluN=Nflu] (3). The reaction of 2 with N,N'‐diisopropylcarbodiimide (iPrN=C=NiPr) affords the aluminium guanidinate complex, Al(NON){N(iPr)C(N=CMe2)N(CHflu)} (4), showing a rare example of reactivity at a metal ketimide ligand. Density functional theory (DFT) calculations have been used to examine the bonding in the newly formed [(fluN2)2]2− ligand in 1 and the ketimide bonding in 2. The mechanism leading to the formation of 4 has also been studied using this technique. [ABSTRACT FROM AUTHOR]

The activation of dinitrogen (N2) by transition metals is central to the highly energy intensive, heterogeneous Haber–Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N2 with d‐ and f‐block metals, though little success has been had with main group metals. Here we report that the reduction of a bulky magnesium(II) amide [(TCHPNON)Mg] (TCHPNON=4,5‐bis(2,4,6‐tricyclohexylanilido)‐2,7‐diethyl‐9,9‐dimethyl‐xanthene) with 5 % w/w K/KI yields the magnesium‐N2 complex [{K(TCHPNON)Mg}2(μ‐N2)]. DFT calculations and experimental data show that the dinitrogen unit in the complex has been reduced to the N22− dianion, via a transient anionic magnesium(I) radical. The compound readily reductively activates CO, H2 and C2H4, in reactions in which it acts as a masked dimagnesium(I) diradical. [ABSTRACT FROM AUTHOR]

The activation of dinitrogen (N2) by transition metals is central to the highly energy intensive, heterogeneous Haber–Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N2 with d‐ and f‐block metals, though little success has been had with main group metals. Here we report that the reduction of a bulky magnesium(II) amide [(TCHPNON)Mg] (TCHPNON=4,5‐bis(2,4,6‐tricyclohexylanilido)‐2,7‐diethyl‐9,9‐dimethyl‐xanthene) with 5 % w/w K/KI yields the magnesium‐N2 complex [{K(TCHPNON)Mg}2(μ‐N2)]. DFT calculations and experimental data show that the dinitrogen unit in the complex has been reduced to the N22− dianion, via a transient anionic magnesium(I) radical. The compound readily reductively activates CO, H2 and C2H4, in reactions in which it acts as a masked dimagnesium(I) diradical. [ABSTRACT FROM AUTHOR]

Background: Opioid overdose deaths in the U.S. continue to increase, largely due to the prevalence of fentanyl, a very powerful opioid, in the illicit drug supply. Buprenorphine treatment is effective for treating opioid use disorder, but it can be challenging for clinicians to introduce buprenorphine treatment to people who use fentanyl due to risks of precipitated withdrawal. Induction could be facilitated through a buprenorphine microdosing approach called "the Bernese method." Objective: In this commentary, we describe how federal laws inadvertently limit optimal use of the Bernese method and how federal laws could be reformed to facilitate use of the Bernese method. Results: The Bernese method requires patients to continue using the opioid of misuse (e.g., fentanyl) for seven to ten days while receiving very low doses of buprenorphine. Under federal law, the typical office-based buprenorphine prescriber can neither prescribe nor administer fentanyl short-term for buprenorphine induction purposes, essentially forcing patients to continue to temporarily obtain fentanyl via the illicit market. Conclusion: The federal government has already indicated its support for increasing buprenorphine access. We argue that the government should permit short-term dispensing of fentanyl to office-based patients undergoing buprenorphine induction. [ABSTRACT FROM AUTHOR]

Reduction of the heteroleptic Ln(III) precursors [Ln(Tp)2(OTf)] (Tp = hydrotris(1-pyrazolyl)borate; OTf = triflate) with either an aluminyl(I) anion or KC8 yielded the adduct-free homoleptic Ln(II) complexes dimeric 1-Eu [{Eu(Tp)(μ-κ1:η5-Tp)}2] and monomeric 1-Yb [Yb(Tp)2]. Complexes 1-Ln have good solubility and stability in both non-coordinating and coordinating solvents. Reaction of 1-Ln with 2 Ph3PO yielded 1-Ln(OPPh3)2. All complexes are intensely coloured and 1-Eu is photoluminescent. The electronic absorption data show the 4f–5d electronic transitions in Ln(II). Single-crystal X-ray diffraction data reveal first μ-κ1:η5-coordination mode of the unsubstituted Tp ligand to lanthanides in 1-Eu. [ABSTRACT FROM AUTHOR]

The chemistry of low valent p-block metal complexes continues to elicit interest in the research community, demonstrating reactivity that replicates and in some cases exceeds that of their more widely studied d-block metal counterparts. The introduction of the first aluminyl anion, a complex containing a formally anionic Al(I) centre charge balanced by an alkali metal (AM) cation, has established a platform for a new area of chemical research. The chemistry displayed by aluminyl compounds is expanding rapidly, with examples of reactivity towards a diverse range of small molecules and functional groups now reported in the literature. Herein we present an account of the structure and reactivity of the growing family of aluminyl compounds. In this context we examine the structural relationships between the aluminyl anion and the AM cations, which now include examples of AM = Li, Na, K, Rb and Cs. We report on the ability of these compounds to engage in bond-breaking and bond-forming reactions, which is leading towards their application as useful reagents in chemical synthesis. Furthermore we discuss the chemistry of bimetallic complexes containing direct Al–M bonds (M = Li, Na, K, Mg, Ca, Cu, Ag, Au, Zn) and compounds with Al–E multiple bonds (E = NR, CR2, O, S, Se, Te), where both classes of compound are derived directly from aluminyl anions. [ABSTRACT FROM AUTHOR]

Building on a pre-existing line of inquiry where the presence of solid particle attractors in thermovibrationally driven flows was demonstrated in cavities subjected to a unidirectional temperature gradient, the present work considers cases where the direction of such a gradient is allowed to change inside the fluid. Moreover, the considered configurations differ with regard to the angle that vibrations form with respect to a reference axis. Variations in the orientation of the temperature gradient are made possible by setting a non-uniform temperature distribution along certain walls. The relationship between the multiplicity (N) of the loci of particle attraction and the inhomogeneities in the temperature field is studied. It is shown that N can exceed the limit N = 2 found in earlier studies and that a zoo of new particle accumulation structures show up, whose ranges of existence depend on the amplitude and frequency of vibrational acceleration, the particle Stokes number, the orientation of vibrations, and the number of inversions in the direction of the temperature gradient. [ABSTRACT FROM AUTHOR]

The reaction of compounds containing Al–Mg and Al–Zn bonds with N2O enabled isolation of the corresponding Al(μ-O)M complexes. Electronic structure analysis identified largely ionic Al–O and O–M bonds, featuring an anionic μ-oxo centre. Reaction with CO2 confirmed that these species correspond to the proposed intermediates in the formation of μ-carbonate compounds. [ABSTRACT FROM AUTHOR]

• New sterically bulky aryl and aliphatic substituted diamide ligands have been reported. • A series of novel germylenes were prepared and their steric profile assessed using computational models. • The extremely bulky 2,4,6-tricyclohexylphenyl substituent provides greater steric protection to the germanium centre, compared to previously reported germylenes incorporating smaller aryl groups, utilising the same ligand back-bone architectures. In this contribution, three novel diamine pro-ligands, incorporating sterically bulky aryl and aliphatic N-substituents, have been developed; viz. (NCNTCHP)H 2 (NCNTCHP = {(TCHP)NCH 2 } 2 CH 2 , TCHP = 2,4,6-tricyclohexylphenyl), (NONTCHP)H 2 (NONTCHP = {(TCHP)NSiMe 2 } 2 O), and (NONAd)H 2 (NONAd = {(Ad)NSiMe 2 } 2 O; Ad = 1-adamantyl). Through salt metathesis or transamination synthetic approaches, the N-heterocyclic germylenes, [:Ge(NCNTCHP)], [:Ge(NONTCHP)], and [:Ge(NONAd)], have been prepared and crystallographically characterized. The electronic structure of each germylene was studied by DFT calculations. The steric profile of the germanium-bound ligands was also assessed using computational models, and the results compared to those for structurally similar compounds. Significant steric crowding of the germanium centre (>70 % ligand coverage) was observed for [:Ge(NCNTCHP)] and [:Ge(NONTCHP)], while [:Ge(NONAd)] exhibited substantially less steric saturation at the metal centre (∼62 % ligand coverage). Through these studies, we have shown the potential suitably of the developed ligands to stabilise other low-valent main-group species. Synopsis: A range of very bulky 6-membered heterocyclic diamido germylenes were synthesised and their structures investigated using X-ray crystallography and computational methods. [Display omitted] [ABSTRACT FROM AUTHOR]

(NONDipp)Al–K(TMEDA)2 (NONDipp = [O(SiMe2NDipp)2]2−, Dipp = 2,6-iPr2C6H3), containing an Al–K bond, activates and reductively couples cabon monoxide gas to form the [C4O4]4− ligand. This oxocarbon anion is thermally isomerised in the presence of CO and TMEDA. In contrast, the dimeric potassium aluminyl [K{Al(NONDipp)}]2 yields an aluminium complex containing the hitherto unknown [C5O5]5− ligand. [ABSTRACT FROM AUTHOR]

The potassium aluminyl [K{Al(NONDipp)}]2 ([NONDipp]2−=[O{SiMe2NDipp}2]2−, Dipp=2,6‐iPr2C6H3) activates ethene towards carbonylation with CO under mild conditions. An isolated bis‐aluminacyclopropane compound reacted with CO via carbonylation of an Al−C bond, followed by an intramolecular hydrogen shift to form K2[Al(NONDipp)(μ‐CH2CH=CO‐1κ2C1,3‐2κO)Al(NONDipp)Et]. Restricting the chemistry to a mono‐aluminium system allowed isolation of [Al(NONDipp)(CH2CH2CO‐κ2C1,3)]−, which undergoes thermal isomerisation to form the [Al(NONDipp)(CH2CH=CHO‐κ2C,O)]− anion. DFT calculations highlight the stabilising influence of incorporated benzene at multiple steps in the reaction pathways. [ABSTRACT FROM AUTHOR]

The potassium aluminyl [K{Al(NONDipp)}]2 ([NONDipp]2−=[O{SiMe2NDipp}2]2−, Dipp=2,6‐iPr2C6H3) activates ethene towards carbonylation with CO under mild conditions. An isolated bis‐aluminacyclopropane compound reacted with CO via carbonylation of an Al−C bond, followed by an intramolecular hydrogen shift to form K2[Al(NONDipp)(μ‐CH2CH=CO‐1κ2C1,3‐2κO)Al(NONDipp)Et]. Restricting the chemistry to a mono‐aluminium system allowed isolation of [Al(NONDipp)(CH2CH2CO‐κ2C1,3)]−, which undergoes thermal isomerisation to form the [Al(NONDipp)(CH2CH=CHO‐κ2C,O)]− anion. DFT calculations highlight the stabilising influence of incorporated benzene at multiple steps in the reaction pathways. [ABSTRACT FROM AUTHOR]

Expanding knowledge of low valent aluminium chemistry, rubidium and caesium aluminyls are reported to complete the group 1 (Li–Cs) set of metal aluminyls. Both compounds crystallize as a contacted dimeric pair supported by M⋯π(arene) interactions with a pronounced twist between aluminyl units. Density functional theory calculations show symmetrical bonding between the M and Al atoms, with an Al centred lone-pair donating into vacant Rb and Cs orbitals. Interestingly, despite their structural similarity the Cs aluminyl enables C–H bond activation of benzene, but not the Rb aluminyl reflecting the importance of the alkali metal in these heterobimetallic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] Yttrium alkyl complex [NONDippY(CH 2 SiMe 3)(THF)], 1 (NONDipp = (DippNSiMe 2) 2 O, Dipp = 2,6- i Pr-C 6 H 3) can be prepared in high yields by a σ-bond metathesis reaction between [Y(CH 2 SiMe 3) 3 (THF) 2 ] and the free bis(aminosilyl)ether. The reaction of 1 with one equivalent of PhSiH 3 generates the hydride bridged yttrium dimer [μ-NONDippY(μ-H)(THF)] 2 2 , however, each diamidosilylether ligand does not chelate each yttrium centre but instead bridges to both yttrium atoms in a "flyover" fashion. This ligand rearrangement maybe reversed by the addition of a strong Lewis base to give the dimeric yttrium hydride [NONDippY(μ-H)(DMAP)] 2 3 , where each diamidosilylether ligand now chelate to each yttrium center respectively. The effect of the different diamidosilylether bonding modes on the reactivity of the yttrium complexes is examined with heterocumulenes. Yttrium alkyl complex [NONDippY(CH 2 SiMe 3)(THF)], 1 (NONDipp = (DippNSiMe 2) 2 O, Dipp = 2,6- i Pr-C 6 H 3) can be prepared in high yields by a σ-bond metathesis reaction between [Y(CH 2 SiMe 3) 3 (THF) 2 ] and the free bis(aminosilyl)ether. The reaction of 1 with one equivalent of PhSiH 3 generates the hydride bridged yttrium dimer [μ-NONDippY(μ-H)(THF)] 2 2 , however, each diamidosilylether ligand does not chelate each yttrium centre but instead bridges to both yttrium atoms in a "flyover" fashion. This ligand rearrangement maybe reversed by the addition of a strong Lewis base to give the dimeric yttrium hydride [NONDippY(μ-H)(DMAP)] 2 3 , where each diamidosilylether ligand now chelate to each yttrium center respectively. The effect of the different diamidosilylether bonding modes on the reactivity of the yttrium complexes is examined with heterocumulenes. [ABSTRACT FROM AUTHOR]

To date, aluminyl anions have been exclusively isolated as their potassium salts. We report herein the synthesis of the lithium and sodium aluminyls, M2[Al(NONDipp)]2 (M=Li, Na. NONDipp=[O(SiMe2NDipp)2]2−; Dipp=2,6‐iPr2C6H3). Both compounds crystallize from non‐coordinating solvent as "slipped" contacted dimeric pairs with strong M⋅⋅⋅π(aryl) interactions. Isolation from Et2O solution affords the monomeric ion pairs (NONDipp)Al‐M(Et2O)2, which contain discrete Al−Li and Al−Na bonds. The ability of the full series of Li, Na and K aluminyls to activate dihydrogen is reported. [ABSTRACT FROM AUTHOR]

To date, aluminyl anions have been exclusively isolated as their potassium salts. We report herein the synthesis of the lithium and sodium aluminyls, M2[Al(NONDipp)]2 (M=Li, Na. NONDipp=[O(SiMe2NDipp)2]2−; Dipp=2,6‐iPr2C6H3). Both compounds crystallize from non‐coordinating solvent as "slipped" contacted dimeric pairs with strong M⋅⋅⋅π(aryl) interactions. Isolation from Et2O solution affords the monomeric ion pairs (NONDipp)Al‐M(Et2O)2, which contain discrete Al−Li and Al−Na bonds. The ability of the full series of Li, Na and K aluminyls to activate dihydrogen is reported. [ABSTRACT FROM AUTHOR]

We report the [Al(NONDipp)(Te)(THF)]− anion containing a terminal aluminium telluride bond. DFT calculations confirm appreciable Al–Te multiple bond character and reaction with CO2 proceeds via a double insertion to afford the previously unknown tellurodicarbonate ligand. [ABSTRACT FROM AUTHOR]

This article reflects upon the neoliberalisation of higher education and its effects on teaching practice. It is argued that a neoliberal discourse of teaching excellence has the effect of working against, and potentially undermining, the emancipatory potential of higher education. The article reflects upon attempts to navigate disciplinary power in the neoliberal university and considers whether critical, emancipatory praxis is possible or if complicity in, and co-option by, neoliberalism is inevitable. Ultimately, it is concluded that individual teachers have some scope to pursue approaches which counter neoliberal dominance but that this is heavily constrained. A broader, collective, project will therefore be necessary if alternative (critical, emancipatory) visions of teaching and learning in higher education are to successfully challenge neoliberal hegemony and the negative effects of this in the academy. [ABSTRACT FROM AUTHOR]

Addition of MesN3 (Mes=2,4,6‐Me3C6H2) to germylene [(NONtBu)Ge] (NONtBu=O(SiMe2NtBu)2) (1) gives germanimine, [(NONtBu)Ge=NMes] (2). Compound 2 behaves as a metalloid, showing reactivity reminiscent of both transition metal‐imido complexes, undergoing [2+2] addition with heterocumulenes and protic sources, as well as an activated diene, undergoing a [4+2] cycloaddition, or "metallo"‐Diels–Alder, reaction. In the latter case, the diene includes the Ge=N bond and π‐system of the Mes substituent, which is reactive towards dienophiles including benzaldehyde, benzophenone, styrene, and phenylacetylene. [ABSTRACT FROM AUTHOR]

1. The AIRE Centre[1] is a charity and specialist law centre founded in 1993 to promote awareness of, and compliance with, European and international law. The AIRE Centre has intervened in over 100 cases before the Strasbourg[2] and Luxembourg Courts.[3] However, in this article I want to concentrate on the domestic work the AIRE Centre has undertaken here in the UK, and specifically in the field of administrative law. 16. This year the AIRE Centre was granted permission by the UKSC to intervene in I Secretary of State for Work and Pensions v Gubeladze i [2019] UKSC 31, which raised fundamental questions of EU law as to the nature of the residence required under Art. 39. The UK courts remain, in the words of Sir Stephen Sedley, "lions under the throne of parliament".[34] None of the cases the AIRE Centre has intervened in has overturned UK legislation, even when we have been successful in persuading the court on the correctness of our legal argument. [Extracted from the article]

This article explores challenges associated with conducting research on social movements in South Africa (and beyond). Scholarship and commentary on South African social movements is a contentious and contested field. This article reflects particularly on carrying out research relating to land and housing rights and on the relationships between scholars, activists and activist-scholars working in this area. There is a particular difficulty with regard to identifying and analysing the political biases present within various opposing accounts of the social movements taking action on land and housing issues and their relationships to other actors. The article argues that there are three main pitfalls which researchers should attempt to avoid. First there is the danger of taking the claims made by social movements and by their academic advocates at face value. The second pitfall, on the other hand, relates to the danger of dismissing the praxis of these social movements altogether. The third danger surrounds the risk of the debates and disagreements between academics and commentators overshadowing discussion of the issues upon which movements work. The article suggests that it is necessary to apply a critical lens to all knowledge produced about social movements taking action on land and housing issues in South Africa and, consequently, a number of questions remain unresolved when attempting to put together an accurate picture of the relationships between and praxis of groups and organisations working in this area. [ABSTRACT FROM AUTHOR]

This article considers lessons recent debates concerning transitional and transformative justice, and surrounding transformative reparations, could offer to discussions regarding reparations for transatlantic slavery. Even transitional justice programmes aiming to provide transformative reparations in the form of development programmes (such as healthcare, education and housing provision) have enabled governments to avoid addressing structural causes of inequalities. The article argues that calling for reparations for transatlantic slavery in the form of development projects is potentially regressive. Framing development programmes as reparations, as parts of the Caribbean Community Ten-Point Plan for reparations do, risks presenting these as necessary only because of powerful states' duty to make amends for past wrongdoing. The article calls for advocates of reparations for transatlantic slavery to be more explicit in demarcating the backward- and forward-looking foundations of their claims. The importance of symbolic and non-financial reparations ought to be more explicitly highlighted as a potential contributor to the social repair of transatlantic slavery's harmful legacies. Moreover, distributive justice should be explicitly emphasized as being necessary to realize the present-day and future rights of people suffering from the historical legacy of transatlantic slavery and not simply because the present situation is the result of historical injustice. [ABSTRACT FROM AUTHOR]

Highlights • Optimal design parameters are dependent on the nature of the physical input. • Frame force amplification is coupled with stack parameters through axial stiffness. • Increasing the width of the device results in an increase in converted energy. • Thin film deposition manufacturing may be required to target low frequency inputs. Abstract Piezoelectric stack energy harvesters have the advantage of generating electrical power for small amounts of deflection. In an underfloor energy harvesting application, this is advantageous as the device does not disrupt the gait of pedestrians overhead. Low frequency, stochastic loading patterns are typical of underfloor applications, where the precise gait, weight and number of pedestrians are unpredictable. Energy harvesters targeting this type of directly applied load are faced with the challenge of providing sufficient force for power generation and determining appropriate matching of the piezoelectric stack to the circuit being powered, to achieve the highest possible energy conversion efficiency. The latter is particularly challenging in the case of stochastic input, due to the piezoelectric stack's dependence on frequency. To address these challenges, a force amplification frame is used in conjunction with a piezoelectric stack to provide an increase of up to 10 times of the applied load to the stack. A method of modelling the energy harvester is presented to optimise the device to suit a range of typical inputs, including walking, jogging and multiple pedestrian loading conditions. The methods used are capable of incorporating measured data from existing support platforms and the behaviour of interfacing power management circuitry into the optimisation loop, providing an accurate means of predicting the response of the energy harvesting system under typical operating conditions. The model is experimentally validated, and the results used to demonstrate a potential power increase of a factor of 21 when compared to an off-the-shelf piezoelectric stack. [ABSTRACT FROM AUTHOR]

Three distinct routes are reported to the soluble, dihydridoaluminate compounds, AM[Al(NONDipp)(H)2] (AM=Li, Na, K, Rb, Cs; [NONDipp]2−=[O(SiMe2NDipp)2]2−; Dipp=2,6‐iPr2C6H3) starting from the alkali metal aluminyls, AM[Al(NONDipp)]. Direct H2 hydrogenation of the heavier analogues (AM=Rb, Cs) produced the first examples of structurally characterized rubidium and caesium dihydridoaluminates, although harsh conditions were required for complete conversion. Using 1,4‐cyclohexadiene (1,4‐CHD) as an alternative hydrogen source in transfer hydrogenation reactions provided a lower energy pathway to the full series of products for AM=Li−Cs. A further moderation in conditions was noted for the thermal decomposition of the (silyl)(hydrido)aluminates, AM[Al(NONDipp)(H)(SiH2Ph)]. Probing the reaction of Cs[Al(NONDipp)] with 1,4‐CHD provided access to a novel inverse sandwich complex, [{Cs(Et2O)}2{Al(NONDipp)(H)}2(C6H6)], containing the 1,4‐dialuminated [C6H6]2− dianion and representing the first time that an intermediate in the commonly utilized oxidation process of 1,4‐CHD to benzene has been trapped. The synthetic utility of the newly installed Al−H bonds has been demonstrated by their ability to reduce CO2 under mild conditions to form the bis‐formate AM[Al(NONDipp)(O2CH)2] compounds, which exhibit a diverse series of eyecatching bimetallacyclic structures. [ABSTRACT FROM AUTHOR]

The maize female gametophyte contains four cell types: two synergids, an egg cell, a central cell, and a variable number of antipodal cells. In maize, these cells are produced after three rounds of free-nuclear divisions followed by cellularization, differentiation, and proliferation of the antipodal cells. Cellularization of the eight-nucleate syncytium produces seven cells with two polar nuclei in the central cell. Nuclear localization is tightly controlled in the embryo sac. This leads to precise allocation of the nuclei into the cells upon cellularization. Nuclear positioning within the syncytium is highly correlated with their identity after cellularization. Two mutants are described with extra polar nuclei, abnormal antipodal cell morphology, and reduced antipodal cell number, as well as frequent loss of antipodal cell marker expression. Mutations in one of these genes, indeterminate gametophyte2 encoding a MICROTUBULE ASSOCIATED PROTEIN65-3 homolog, shows a requirement for MAP65-3 in cellularization of the syncytial embryo sac as well as for normal seed development. The timing of the effects of ig2 suggests that the identity of the nuclei in the syncytial female gametophyte can be changed very late before cellularization. [ABSTRACT FROM AUTHOR]

Non-pathogenic Bacillus species used in cleaning products produce the appropriate enzymes to degrade stains and soils. However, there is little scientific data regarding the human exposure by inhalation of Bacillus spores during or after use of microbial-based cleaning products. Herein, air samples were collected at various locations in a ventilated, carpeted, residential room to determine the air concentration of viable bacteria and spores during and after the application of microbial-based carpet cleaning products containing Bacillus spores. The influence of human activities and vacuuming was investigated. Bioaerosol levels associated with use and post-application activities of whole room carpet treatments were elevated during post-application activity, but quickly returned to the indoor background range. Use of trigger spray spot applications generated aerosolized spores in the immediate vicinity, however, their use pattern and the generation of mostly non-respirable particles suggest minimal risks for pulmonary exposure from their use. The aerosol counts associated with use of these microbial-based cleaners were below the recommendation for safe exposure levels to non-pathogenic and non-toxigenic microorganisms except during application of the spot cleaner. The data presented suggest that carpet cleaning products, containing non–pathogenic Bacillus spores present a low potential for inhalation exposure and consequently minimal risk of adverse effects. [ABSTRACT FROM AUTHOR]

Long-distance signalling is important for coordinating plant responses to the environment. Variation potentials ( VPs) are a type of long-distance electrical signal that are generated in plants in response to wounding or flaming. Unlike self-propagating action potentials, VPs can be measured beyond regions of dead or chemically treated tissue that block signal generation, suggesting a different mode of propagation. Two alternative propagation mechanisms have been proposed: movement of a chemical agent and a pressure wave through the vasculature. Variants of these two signalling mechanisms have been suggested. Here, we use simple models of the underlying physical processes to evaluate and compare these predictions against independent data. Our models suggest that chemical diffusion and pressure waves are unlikely to capture existing data with parameters that are known from other sources. The previously discarded hypothesis of mass flow in the xylem transporting a chemical agent, however, is able to reproduce experimental propagation speeds for VPs. We therefore suggest that chemical agents transported by mass flow within the xylem are more likely than a pressure wave or chemical diffusion as a VP propagation mechanism. Understanding this mode of long-distance signalling within plants is important for unravelling how plants coordinate physiological responses via cell-to-cell communication. [ABSTRACT FROM AUTHOR]

Rapid, safe and effective arterial recanalisation to restore blood flow and improve functional outcome remains the primary goal of hyperacute ischaemic stroke management. The benefit of intravenous thrombolysis with recombinant tissue-type plasminogen activator for patients with severe stroke due to large artery occlusion is limited; early recanalisation is generally less than 30% for carotid, proximal middle cerebral artery or basilar artery occlusion. Since November 2014, nine positive randomised controlled trials of mechanical thrombectomy for large vessel occlusion in the anterior circulation have led to a revolution in the care of patients with acute ischaemic stroke. Its efficacy is unmatched by any previous therapy in stroke medicine, with a number needed to treat of less than 3 for improved functional outcome. With effectiveness shown beyond any reasonable doubt, the key challenge now is how to implement accessible, safe and effective mechanical thrombectomy services. This review aims to provide neurologists and other stroke physicians with a summary of the evidence base, a discussion of practical aspects of delivering the treatment and future challenges. We aim to give guidance on some of the areas not clearly described in the clinical trials (based on evidence where available, but if not, on our own experience and practice) and highlight areas of uncertainty requiring further research. [ABSTRACT FROM AUTHOR]

The combination of tongue hemianaesthesia, dysgeusia, dysarthria and dysphagia suggests the involvement of multiple cranial nerves. We present a case with sudden onset of these symptoms immediately following wisdom tooth extraction and highlight the clinical features that allowed localisation of the lesion to a focal, iatrogenic injury of the lingual nerve and adjacent styloglossus muscle. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis (TB) poses a serious threat for agricultural industry in several countries, it involves potential interactions between wildlife and cattle and creates societal problems in terms of human-wildlife conflict. This study addresses connectedness network analysis, the spatial, and temporal dynamics of TB between cattle in farms and the European badger ( Meles meles) using a large dataset generated by a calibrated agent based model. Results showed that infected network connectedness was lower in badgers than in cattle. The contribution of an infected individual to the mean distance of disease spread over time was considerably lower for badger than cattle; badgers mainly spread the disease locally while cattle infected both locally and across longer distances. The majority of badger-induced infections occurred when individual badgers leave their home sett, and this was positively correlated with badger population growth rates. Point pattern analysis indicated aggregation in the spatial pattern of TB prevalence in badger setts across all scales. The spatial distribution of farms that were not TB free was aggregated at different scales than the spatial distribution of infected badgers and became random at larger scales. The spatial cross correlation between infected badger setts and infected farms revealed that generally infected setts and farms do not coexist except at few scales. Temporal autocorrelation detected a two year infection cycle for badgers, while there was both within the year and longer cycles for infected cattle. Temporal cross correlation indicated that infection cycles in badgers and cattle are negatively correlated. The implications of these results for understanding the dynamics of the disease are discussed. [ABSTRACT FROM AUTHOR]

The anatomical localisation of brainstem syndromes is the domain of the clinical neurologist, though MRI has made an encyclopaedic knowledge of neuroanatomy less crucial. Isolated pontine syndromes comprise ~20% of the brainstem lacunar syndromes. Typical presentations such as pure motor hemiparesis and ataxic hemiparesis are easily recognisable but atypical syndromes, particularly when bilateral, may present with puzzling signs. We discuss a patient with an unusual acute bilateral brainstem syndrome, in whom MRI was contraindicated. We use the relevant neuroanatomy to support the likely diagnosis of bilateral caudal pontine tegmentum infarction due to occlusion of a single paramedian pontine tegmental perforating artery. [ABSTRACT FROM AUTHOR]

Objective: A number of promising experimental therapies for Duchenne muscular dystrophy (DMD) are emerging. Clinical trials currently rely on invasive biopsies or motivation-dependent functional tests to assess outcome. Quantitative muscle magnetic resonance imaging (MRI) could offer a valuable alternative and permit inclusion of non-ambulant DMD subjects. The aims of our study were to explore the responsiveness of upper-limb MRI muscle-fat measurement as a non-invasive objective endpoint for clinical trials in non-ambulant DMD, and to investigate the relationship of these MRI measures to those of muscle force and function. Methods: 15 non-ambulant DMD boys (mean age 13.3 y) and 10 age-gender matched healthy controls (mean age 14.6 y) were recruited. 3-Tesla MRI fat-water quantification was used to measure forearm muscle fat transformation in non-ambulant DMD boys compared with healthy controls. DMD boys were assessed at 4 time-points over 12 months, using 3-point Dixon MRI to measure muscle fat-fraction (f.f.). Images from ten forearm muscles were segmented and mean f.f. and cross-sectional area recorded. DMD subjects also underwent comprehensive upper limb function and force evaluation. Results: Overall mean baseline forearm f.f. was higher in DMD than in healthy controls (p<0.001). A progressive f.f. increase was observed in DMD over 12 months, reaching significance from 6 months (p<0.001, n = 7), accompanied by a significant loss in pinch strength at 6 months (p<0.001, n = 9) and a loss of upper limb function and grip force observed over 12 months (p<0.001, n = 8). Conclusions: These results support the use of MRI muscle f.f. as a biomarker to monitor disease progression in the upper limb in non-ambulant DMD, with sensitivity adequate to detect group-level change over time intervals practical for use in clinical trials. Clinical validity is supported by the association of the progressive fat transformation of muscle with loss of muscle force and function. [ABSTRACT FROM AUTHOR]

Background: Calcium signalling relies on the flux of calcium ions across membranes yet how signals in different compartments are related remains unclear. In particular, similar calcium signals on both sides of the nuclear envelope have been reported and attributed to passive diffusion through nuclear pores. However, observed differing cytosolic and nucleosolic calcium signatures suggest that the signalling machinery in these compartments can act independently. Results: We adapt the fire-diffuse-fire model to investigate the generation of perinuclear calcium oscillations. We demonstrate that autonomous spatio-temporal calcium patterns are still possible in the presence of nuclear and cytosolic coupling via nuclear pores. The presence or absence of this autonomy is dependent upon the strength of the coupling and the maximum firing rate of an individual calcium channel. In all cases, coupling through the nuclear pores enables robust signalling with respect to changes in the diffusion constant. Conclusions: We show that contradictory interpretations of experimental data with respect to the autonomy of nuclear calcium oscillations can be reconciled within one model, with different observations being a consequence of varying nuclear pore permeabilities for calcium and refractory conditions of channels. Furthermore, our results provide an explanation for why calcium oscillations on both sides of the nuclear envelope may be beneficial for sustained perinuclear signaling. [ABSTRACT FROM AUTHOR]

Woodlands provide valuable ecosystem services, and it is important to understand their dynamics. To predict the way in which these might change, we need process-based predictive ecological models, but these are necessarily very data intensive. We tested the ability of existing datasets to provide the parameters necessary to instantiate a well-used forest model ( SORTIE) for a well-studied woodland (Wytham Woods). Only five of SORTIE's 16 equations describing different aspects of the life history and behavior of individual trees could be parameterized without additional data collection. One age class - seedlings - was completely missed as they are shorter than the height at which Diameter at Breast Height (DBH) is measured. The mensuration of trees has changed little in the last 400 years (focussing almost exclusively on DBH) despite major changes in the nature of the source of value obtained from trees over this time. This results in there being insufficient data to parameterize process-based models in order to meet the societal demand for ecological prediction. We do not advocate ceasing the measurement of DBH, but we do recommend that those concerned with tree mensuration consider whether additional measures of trees could be added to their data collection protocols. We also see advantages in integrating techniques such as ground-based LIDAR or remote sensing techniques with long-term datasets to both preserve continuity with what has been performed in the past and to expand the range of measurements made. [ABSTRACT FROM AUTHOR]

Plants exhibit rapid, systemic signaling systems that allow them to coordinate physiological and developmental responses throughout the plant body, even to highly localized and quickly changing environmental stresses. The propagation of these signals is thought to include processes ranging from electrical and hydraulic networks to waves of reactive oxygen species (ROS) and cytoplasmic Ca2+ traveling throughout the plant. For the Ca2+ wave system, the involvement of the vacuolar ion channel TWO PORE CHANNEL1 (TPC1) has been reported. However, the precise role of this channel and the mechanism of cell-to-cell propagation of the wave have remained largely undefined. Here, we use the fire-diffuse-fire model to analyze the behavior of a Ca2+ wave originating from Ca2+ release involving the TPC1 channel in Arabidopsis (Arabidopsis thaliana). We conclude that a Ca2+ diffusion-dominated calcium-induced calcium-release mechanism is insufficient to explain the observed wave transmission speeds. The addition of a ROS-triggered element, however, is able to quantitatively reproduce the observed transmission characteristics. The treatment of roots with the ROS scavenger ascorbate and the NADPH oxidase inhibitor diphenyliodonium and analysis of Ca2+ wave propagation in the Arabidopsis respiratory burst oxidase homolog D (AtrbohD) knockout background all led to reductions in Ca2+ wave transmission speeds consistent with this model. Furthermore, imaging of extracellular ROS production revealed a systemic spread of ROS release that is dependent on both AtRBOHD and TPC1. These results suggest that, in the root, plant systemic signaling is supported by a ROS-assisted calcium-induced calcium-release mechanism intimately involving ROS production by AtRBOHD and Ca2+ release dependent on the vacuolar channel TPC1. [ABSTRACT FROM AUTHOR]

The article discusses behavioral studies of Cuban Crocodile Crocodylus rhombifer alongwith information on observations made at the Smithsonian National Zoological Park in Washington, D.C. It reveals that object play is the most common type of play reported in crocodilians. It also mentions play types such as locomotion play, social play and object play and also reveals that C. rhombifer is in serious danger of extinction.

Bovine tuberculosis (TB) is a chronic disease in cattle that causes a serious food security challenge to the agricultural industry in terms of dairy and meat production. Spatio-temporal disease analysis in terms of time trends and geographic disparities of disease dynamics can provide useful insights into the overall efficiency of control efforts as well as the relative efficiency of different management measures towards eradication. In GB, Scotland has had a risk based surveillance testing policy under which high risk herds are tested frequently, and in September 2009 was officially declared as TB free. Wales have had an annual or more frequent testing policy for all cattle herds since January 2010, while in England several herds are still tested every 4 years except some high TB prevalence areas where annual testing is applied. Time series analysis using publicly available data for total tests on herds, total cattle slaughtered, new herd incidents, and herds not TB free, were analysed globally for GB and locally for the constituent regions of Wales, Scotland, West, North, and East England. After detecting trends over time, underlying regional differences were compared with the testing policies in the region. Total cattle slaughtered are decreasing in Wales, Scotland and West England, but increasing in the North and East English regions. New herd incidents, i.e., disease incidence, are decreasing in Wales, Scotland, West English region, but increasing in North and East English regions. Herds not TB free, i.e., disease prevalence, are increasing in West, North, and East English regions, while they are decreasing in Wales and Scotland. Total cattle slaughtered were positively correlated with total tests in the West, North, and East English regions, with high slopes of regression indicating that additional testing is likely to facilitate the eradication of the disease. There was no correlation between total cattle slaughtered and total tests on herds in Wales indicating that herds are tested frequent enough in order to detect all likely cases and so control TB. The main conclusion of the analysis conducted here is that more frequent testing is leading to lower TB infections in cattle both in terms of TB prevalence as well as TB incidence. [ABSTRACT FROM AUTHOR]

This study is concerned with the determination of the degree of polymerisation (DP) of fructans from chicory and rye-grass ( Lolium perenne L.) using Gel Permeation Chromatography coupled to multiangle laser light scattering and refractive index detectors (GPC/MALLS) and Matrix-Assisted Laser Desorption/Ionisation Time of Flight Mass Spectrometry (MALDI-TOF MS). The results show that fructans isolated from ryegrass have a DP in the range 2–>100 and the commercially produced fructans derived from chicory have a DP in range 2–61. It has been demonstrated that MALDI-TOF MS is particularly effective at determining the DP of low molar mass material but is less effective for detecting the presence of high DP molecules. On the other hand GPC/MALLS is able to provide a much broader range of DP values although it is less sensitive at very low DP. It has been shown that the two techniques give complementary information thus providing a more accurate estimate of the overall DP of the fructan molecules. [ABSTRACT FROM AUTHOR]

This article provides a critique of the scope of existing models of transitional justice, which focus on legal and quasi-legal remedies for a narrow set of civil and political rights violations. The article highlights the significance of structural violence in producing and reproducing violations of human rights, particularly of socioeconomic rights. There is a need to utilize a different toolkit and a different understanding of human rights from that typically employed in transitional justice in order to remedy structural violations of human rights. Focusing on a case study of land inequalities in postapartheid South Africa, the potential for transformative (rather than transitional) justice in postconflict and postauthoritarian contexts is discussed. The article outlines a definition of transformative justice, relevant actors, and relationships for such an agenda and discusses the kinds of strategies that promise a more transformative approach. [ABSTRACT FROM PUBLISHER]

An association between metabolic abnormalities, hypercholesterolemia and affective disorders is now well recognized. Less well understood are the molecular mechanisms, both in brain and in the periphery, that underpin this phenomenon. In addition to hepatic lipid accumulation and inflammation, C57BL/6J mice fed a high-cholesterol diet (0.2%) to induce non-alcoholic fatty liver disease (NAFLD), exhibited behavioral despair, anxiogenic changes, and hyperlocomotion under bright light. These abnormalities were accompanied by increased expression of transcript and protein for Toll-like receptor 4, a pathogen-associated molecular pattern (PAMP) receptor, in the prefrontal cortex and the liver. The behavioral changes and Tlr4 expression were reversed ten days after discontinuation of the high-cholesterol diet. Remarkably, the dietary fat content and body mass of experimental mice were unchanged, suggesting a specific role for cholesterol in the molecular and behavioral changes. Expression of Sert and Cox1 were unaltered. Together, our study has demonstrated for the first time that high consumption of cholesterol results in depression- and anxiety-like changes in C57BL/6J mice and that these changes are unexpectedly associated with the increased expression of TLR4, which suggests that TLR4 may have a distinct role in the CNS unrelated to pathogen recognition. [ABSTRACT FROM AUTHOR]

Charcot--Marie--Tooth disease is the commonest inherited neuromuscular disease. It is characterised by degeneration of peripheral sensory and motor nerves and can be classified into axonal and demyelinating forms. This review provides a diagnostic approach to patients with suspected inherited neuropathy and an algorithm for genetic testing that includes recent advances in genetics such as next-generation sequencing. We also discuss important aspects of the long-term management of patients with inherited neuropathy. [ABSTRACT FROM AUTHOR]

Parametric instabilities have long been studied as a potentially limiting effect in high-power interferometric gravitational wave detectors. Until now, however, these instabilities have never been observed in a kilometer-scale interferometer. In this Letter, we describe the first observation of parametric instability in a gravitational wave detector, and the means by which it has been removed as a barrier to progress. [ABSTRACT FROM AUTHOR]