A third polymorph of N,N′-bis­(pyridin-2-yl)benzene-1,4-diamine

A third polymorph of the title compound, C16H14N4, has been obtained. The mol­ecule adopts a non-planar conformation with an E configuration at the two partially double exo C N bonds of the 2-pyridyl­amine units. Like in the triclinic form [Bensemann et al. (2002 ▶). New J. Chem. 26, 448–456], the recognition process between 2-pyridyl­amine units takes place through formation of a cyclic R 2 2(8) hydrogen-bond motif, leading to the creation of tapes parallel to [001]

Directing the Self-Assembly of Aromatic Foldamer Helices using Acridine Appendages and Metal Coordination

Abstract Folded molecules provide complex interaction interfaces amenable to sophisticated self-assembly motifs. Because of their high conformational stability, aromatic foldamers constitute suitable candidates for the rational elaboration of self-assembled architectures. Several multiturn helical aromatic oligoamides have been synthesized that possess arrays of acridine appendages pointing in one or two directions. The acridine units were shown to direct self-assembly in the solid state via aromatic stacking leading to recurrent helix-helix association patterns under the form of discrete dimers or extended arrays. In the presence of Pd(II), metal coordination of the acridine units overwhelms other forces and generates new metal-mediated multihelical self-assemblies, including macrocycles. These observations demonstrate simple access to different types of foldamer-containing architectures, ranging from discrete objects to 1D and, by extension, 2D and 3D arrays

Bureaucracy and the challenges of coordination in service delivery : a comparative study of Kabulonga and Kamanga primary schools in Lusaka City, 2010- 2014

Masters in Public Administration - MPAThe study Bureaucracy and the challenges of coordination in service delivery: A comparative study of Kamanga and Kabulonga Primary Schools in Lusaka City 2010- 2014 had the main aim of finding out the challenges encountered in the coordination of primary education within Lusaka City. The study was attempting to draw lessons and understand why schools within the same district and level (primary) were performing differently. There are many reasons as to why the study is important. To begin with, the information derived from this study is important in the post MDG implementation period after the end of the implementation period in 2015. Second, no research has been done on organizational design and development in the context of Africa and Zambia. While some scholars have published on education management, the aspect of bureaucratic coordination has not been adequately addressed. The study took a comparative approach to research. Qualitative research was deployed as means of carrying out the study. Both primary and secondary data were used. Primary data was collected from two schools which were sampled purposively. The researcher approached the District education office to recommend two schools (one performing well and another underperforming one). The two schools recommended are Kabulonga Primary and Kamanga Primary respectively. A sample of seven experts was then extracted including two teachers from each school, a school manager for each school and the district planning officer at district level. Data was collected using semi structured interview guides between December 2015 and January 2016. Data was collected through a recorder, transcribed and analyzed using thematic analysis. On the other hand, secondary data was obtained from policy, legal, government and internal documents. Among the major findings was that the school's locations or environments have a major impact on how they function. For instance Kabulonga performed better than Kamanga because the latter is in an area where majority are low earning poor households. Further, internally, the ability of Kabulonga to plan in a long term manner enabled the school to match resources with specific priorities, something Kamanga did not do. Furthermore, the avenues used for communication in the district have got poor information feedback mechanisms. The study thus recommended that the government should distribute resources to schools with a connotation of giving an extra financial bell out to those schools operating in poverty stricken areas since such schools cannot find other means of survival

Loading linear arrays of Cu(II) inside aromatic amide helices

The very stable helices of 8-amino-2-quinolinecar-boxylic acid oligoamides are shown to uptake CuIIions in theircavity through deprotonation of their amide functions with minimal alteration of their shape, unlike most metallo-organicstructures which generally differ from their organic precursors.The outcome is the formation of intramolecular linear arrays of a defined number of CuIIcenters (up to sixteen in this study)at a 3 distance, forming a molecular mimic of a metal wirecompletely surrounded by an organic sheath. The helices packin the solid state so that the arrays of CuIIextend intermolecularly. Conductive-AFM and cyclic voltammetry suggest thatelectrons are transported throughout the metal-loaded helices in contrast with hole transport observed for analogous foldamers devoid of metal ions.Les voies de signalisation du récepteur 5-HT6: de nouvelles cibles pour le traitement de la douleur neuropathique

Diverse values of nature for sustainability

Twenty-five years since foundational publications on valuing ecosystem services for human well-being1,2, addressing the global biodiversity crisis3 still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever4. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF)5 and the UN Sustainable Development Goals6, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature7. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change8, pandemic emergence9 and socio-environmental injustices10. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions7,11. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures

Diverse values of nature for sustainability

Twenty-five years since foundational publications on valuing ecosystem services for human well-being(1,2), addressing the global biodiversity crisis(3) still implies confronting barriers to incorporating nature's diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever(4). Notwithstanding agreements to incorporate nature's values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF)(5) and the UN Sustainable Development Goals(6), predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature(7). Arguably, a 'values crisis' underpins the intertwined crises of biodiversity loss and climate change(8), pandemic emergence(9) and socio-environmental injustices(10). On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature's diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions(7,11). Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures

Diverse values of nature for sustainability

Twenty-five years since foundational publications on valuing ecosystem services for human well-being, addressing the global biodiversity crisis still implies confronting barriers to incorporating nature’s diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever. Notwithstanding agreements to incorporate nature’s values into actions, including the Kunming-Montreal Global Biodiversity Framework (GBF) and the UN Sustainable Development Goals, predominant environmental and development policies still prioritize a subset of values, particularly those linked to markets, and ignore other ways people relate to and benefit from nature. Arguably, a ‘values crisis’ underpins the intertwined crises of biodiversity loss and climate change, pandemic emergence and socio-environmental injustices. On the basis of more than 50,000 scientific publications, policy documents and Indigenous and local knowledge sources, the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) assessed knowledge on nature’s diverse values and valuation methods to gain insights into their role in policymaking and fuller integration into decisions. Applying this evidence, combinations of values-centred approaches are proposed to improve valuation and address barriers to uptake, ultimately leveraging transformative changes towards more just (that is, fair treatment of people and nature, including inter- and intragenerational equity) and sustainable futures

Studies on crystal chemistry of multicomponent crystals formed by organic compounds

Wydział Chemii: Zakład KrystalografiiCelem rozprawy doktorskiej było zbadanie zdolności do współkrystalizacji rifampicyny, gossypolu oraz kwasu glicyretynowego. Otrzymane struktury krystaliczne pokazały, że rifampicyna w kryształach występuje zarówno w formie fenolowej jak i fenolanowej. W kryształach z formą fenolową powtarzalne motywy strukturalne to dimery oraz łańcuchy cząsteczek. W solwatach z formą fenolanową powtarzającym się motywem są warstwy cząsteczek rifampicyny, których ułożenie dostosowywane jest objętości cząsteczek rozpuszczalnika. Badania rozkładu dwóch form solwatowanych pokazały, że produktem desolwatacji jest forma polimorficzna II rifampicyny. Otrzymane dwu i trójskładnikowe związki inkluzyjne gossypolu należą do V typu strukturalnego. W oparciu o struktury układów dwuskładnikowych zaproponowano mechanizm transformacji związków z grupy Va do związków grupy Vd. Związki trójskładnikowe o stechiometrii 4:2:1 mają budowę analogiczną do związków z grupy Vb. Związki o stechiometrii 4:4:1 mają cechy budowy zarówno związków z grupy Va jak i Vd. W otrzymanych solwatach cząsteczki kwasu glicyretynowego poprzez wiązania wodorowe układają się 'głowa do ogona'. Kształt utworzonych asocjatów może być bardzo różny. Upakowanie w kryształach z cząsteczką aromatyczną jest w dużej mierze dyktowane przez oddziaływania π-π cząsteczek. Rozkład solwatów kwasu glicyretynowego przebiegał stopniowo i prowadził do otrzymania polimorfu trójskośnego.The goal of this dissertation was preparation of multicomponent crystals of rifampicin, gossypol and glycyrrhetinic acid. Based on the crystal structures of the rifampicin crystalline forms it was concluded that in the crystals rifampicin molecule can exist both in phenolic or phenolate forms. In the crystal structures with phenolic form recurrent structural motifs were dimers and chains of rifampicin molecules. In the solvates with phenolate form a densely packed layers was indicated as the common structural motif. The arrangement of these layers can be adjusted to spacial requirements of the solvent. Desolvation process of two solvates with phenolate form result with polymorph II of rifampicin. Two- or three-component crystals with gossypol molecule belong to the type V of gossypol inclusion compounds. Based on the analysis of crystal packing of two component inclusion compounds mechanisms for their gradual transformation was proposed. Three component compounds with stoichiometry of 4:2:1 have the structure characteristic for group Vb. Compounds with 4:4:1 stoichiometry have structural features of Va and Vd groups. In the solvates glycyrrhetinic acid molecules through hydrogen bonds are joined together in ‘head to tail’ fashion. The created hydrogen-bond assemblies are of very divers shapes. Crystal packing in crystals with aromatic molecule is to a large extent determined by π-π stacking interactions. Desolvation process of the solvates was gradual and always led to the triclinic polymorphic form