Synthesis, Properties, and Solid-State Structures of a Series of 6,13-Dicyanoheteropentacene Analogues: Towards New Liquid Crystalline Materials

The focus of this thesis is the synthesis of novel heterocyclic pentacene analogs and the investigation of their self-organization for the development of new materials for organic electronics. The thesis consists of two interrelated projects: the first being development of an improved synthesis of a series of liquid crystalline dicyanotetraoxapentacenes (DCTOPs) while the second entails the exploratory synthesis of several novel dicyanoheteropentacene analogues and a preliminary investigation of their photophysical properties and solid-state structures. Both of these projects centre around the use of nucleophilic aromatic substitution reactions on tetrafluoroterephthalonitrile. Soluble, tetrakis(bis(alkoxy)phenyl)-substituted DCTOPs were originally synthesised via a short synthesis complicated by a tedious purification required in the last step. Despite this, derivatives bearing long alkyl chains were prepared which displayed liquid crystalline properties in addition to aggregation-induced emission. Building upon this success, but with the goal of achieving DCTOPs in an efficient synthetic manner for this thesis, changes were made which eliminated the troublesome fourfold Suzuki coupling by changing the order of reactions, which in turn required a protection-deprotection sequence. Purification in the new synthesis was greatly simplified and the target tetraaryl-DCTOPs were accessed in good overall yields and purities. The synthesis and solid state structures of these DCTOPs are discussed in Chapter 2. Building on the methods developed in Chapter 2, several novel pentacene analogues containing combinations of nitrogen, oxygen, and sulfur atoms installed within the pentacene core were also synthesised. These compounds were prepared in good yields, and preliminary photophysical studies show that all the compounds displayed luminescence in solution and the solid state. It was also shown that replacement of O with N leads to a red shift in absorption and emission spectra. The X-ray crystal structures show that several of these compounds exhibit π−stacking in the solid state, which is an important design element for applications in organic electronics. The synthesis, photophysical properties, and solid-state organization of these novel 6,13-dicyanoheteropentacene analogues are discussed in Chapter 3

Parenting in the early years and self-harm in adolescence: The role of control and reward systems in childhood

Background: Research suggests that early parenting may contribute to the development of self-harm but this has not been examined longitudinally. In this study, we explored the relationship between early parenting and selfharm in adolescence and considered whether (1) emotion regulation and (2) decision-making in childhood mediate the relationship between early parenting and self-harm. // Method: Using longitudinal data from the Millennium Cohort Study (MCS), we tested mediation models exploring the relationship between early parenting and self-harm in adolescence via emotion regulation and decisionmaking. Parenting was assessed at age 3 with measures of conflict, closeness and discipline. The trajectories of independence & self-regulation and emotional dysregulation were modelled from ages 3 to 7 years through latent growth curve analysis, with individual predicted slope and intercept values used in the mediation models. Decision-making (deliberation time, total time, delay aversion, quality of decision making, risk adjustment, risktaking) was assessed using the Cambridge Gambling Task (CGT) at age 11. // Results: In our sample (n = 11,145), we found no evidence of a direct association between early parenting and self-harm in adolescence. However, there were indirect effects of parenting (conflict and closeness) on self-harm via the slope of emotional dysregulation. Furthermore, delay aversion was positively associated with self-harm in adolescence. // Limitations: It must be acknowledged that we cannot determine causality and that self-report measures of parenting are vulnerable to several biases. // Conclusion: The findings support early identification and interventions for children exhibiting chronic emotional dysregulation and decision-making characterised by a bias for smaller, immediate over larger, delayed rewards

Aquachlorido(2-{[6-(dimethylamino)pyrimidin-4- yl]sulfanyl}pyrimidine-4,6-diamine)copper(II) chloride hydrate

A copper(II) complex of the non-symmetric bidentate ligand 2-{[6-(di­methyl­amino)­pyrimidin-4-yl]sulfan­yl}pyrimidine-4,6-di­amine (L1) is reported. The single-crystal X-ray structure of aqua­[aqua/chlorido­(0.49/0.51)](2-{[6-(di­methyl­amino)­pyrimidin-4-yl]sulfan­yl}pyrimidine-4,6-di­amine)­copper(II) 0.49-chloride 1.51-hydrate, [CuCl1.51(C10H13N7S)(H2O)1.49]Cl0.49·1.51H2O or [(L1)Cl1.51(H2O)1.49Cu]0.49Cl·1.51H2O, exhibits distorted square-pyramidal geometry around the metal centre, with disorder in the axial position, occupied by chloride or water. The six-membered metal–chelate ring is in a boat conformation, and short inter­molecular S- - -S inter­actions are observed. In addition to its capacity for bidentate metal coordination, the ligand has the ability to engage in further supra­molecular inter­actions as both a hydrogen-bond donor and acceptor, and multiple inter­actions with lattice solvent water mol­ecules are present in the reported structure

Проблема достоверности научного знания

Знание в самом общем виде можно определить как верное отражение в сознании человека явлений материального и духовного мира и, в частности, многообразных явлений общественной жизни

Could psoralen plus ultraviolet A1 (“PUVA1”) work? Depth penetration achieved by phototherapy lamps

Funding: PhD Studentship UK EPRSC EP/N509759/1.Psoralen and ultraviolet A (PUVA) is useful in treating various hand and foot skin diseases.1 Most cases of psoriasis respond well to phototherapy or PUVA. However, for some diseases, such as palmoplantar pustular psoriasis, PUVA is not always sufficient to produce therapeutic effect. If PUVA fails, it is sometimes necessary to progress to other treatments such as Grenz ray therapy (where available),2 systemic retinoid or systemic immunosuppression. Could “PUVA1” (psoralen combined with ultraviolet A1 long wavelength ultraviolet A [UVA]) work in cases where conventional PUVA (psoralen plus broadband UVA) has been inadequate?PostprintPeer reviewe

Distribution of Short-finned Squid (IIlex illecebrosus) Larvae and Juveniles in Relation to the Gulf Stream Frontal Zone Between Florida and Cape Hatteras

Catches of rhynchoteuthion type C' larvae, which are considered to be II/ex illecebrosus, and I. il/ecebrosus juveniles over the edge of the continental shelf between Cape Hatteras and Florida are examined in relation to the water masses and their dynamics along the Gulf Stream~Slope Water frontal zone. All larvae and juveniles were captured at stations where the temperature~salinity (T-S) properties of the upper 50 m of the water column were closely grouped, with temperatures of 21.0° to 23.5° C and salinities of 36.30 to 36.80, which are very similar to those of Continental Edge Water. Although the actual depths of capture of the larvae and juveniles in the bongo and midwater trawl tows are unknown, it is likely that the majority were taken in the upper 50 m. Larvae and juveniles were intermixed along the entire frontal zone, but there are indications of some differences in microscale distribution. Although juveniles were nearly always captured at stations where larvae were taken, larvae were captured at only 44% of the stations where juveniles were found. The intermixture of larvae and juveniles with a broad range of size (mantle length) indicates that spawning occurs either along the Gulf Stream~Slope Water frontal zone south of Cape Hatteras or in a relatively small area to the south of the surveyed area. The possible role of frontal eddies in causing the intermixture of larvae and juveniles is discussed