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The assessment of intramolecular hydrogen bonding in ortho-substituted anilines by an NMR method
Get PDFYesWe describe the Δlog P method for the assessment of intramolecular hydrogen bonds (IMHBs), and show that it is not a very general method of distinguishing between molecules in which there is an IMHB and molecules in which there is no IMHB. The ‘double’ Δlog P method of Shalaeva et al. is a much more reliable method for the assessment of IMHB but requires the synthesis of a model compound and the determination of no less than four water-solvent partition coefficients. In addition, it is difficult to apply to compounds that contain more than one hydrogen bond acidic group capable of IMHB. We then describe our NMR method of assessing IMHB, based on 1H NMR chemical shifts in solvents DMSO and CDCl3. We have determined 1H NMR chemical shifts for a number of ortho-substituted anilines and show that the only compound we have studied that forms an IMHB is methyl 2-methylaminobenzoate though there is no IMHB present in methyl 2-aminobenzoate. This apparently anomalous result is supported by both MM and ab initio calculations.
The NMR method is much simpler and less time consuming than other methods for the assessment of IMHB. It provides a quantitative assessment of IMHB and can be applied to molecules with more than one hydrogen bond acidic group
Multi-Proxy Characterisation of the Storegga Tsunami and Its Impact on the Early Holocene Landscapes of the Southern North Sea
Get PDFYesDoggerland was a landmass occupying an area currently covered by the North Sea until marine inundation took place during the mid-Holocene, ultimately separating the British landmass from the rest of Europe. The Storegga Event, which triggered a tsunami reflected in sediment deposits in the northern North Sea, northeast coastlines of the British Isles and across the North Atlantic, was a major event during this transgressive phase. The spatial extent of the Storegga tsunami however remains unconfirmed as, to date, no direct evidence for the event has been recovered from the southern North Sea. We present evidence of a tsunami deposit in the southern North Sea at the head of a palaeo-river system that has been identified using seismic survey. The evidence, based on lithostratigraphy, geochemical signatures, macro and microfossils and sedimentary ancient DNA (sedaDNA), supported by optical stimulated luminescence (OSL) and radiocarbon dating, suggests that these deposits were a result of the tsunami. Seismic identification of this stratum and analysis of adjacent cores showed diminished traces of the tsunami which was largely removed by subsequent erosional processes. Our results confirm previous modelling of the impact of the tsunami within this area of the southern North Sea, and also indicate that these effects were temporary, localized, and mitigated by the dense woodland and topography of the area. We conclude that clear physical remnants of the wave in these areas are likely to be restricted to now buried, palaeo-inland basins and incised river valley systems
A tale of two utopias: Work in a post-growth world
Get PDFYesIn this paper, we aim to contribute to the literature on post-growth futures. Modern imaginings of the future are constrained by the assumptions of growth-based capitalism. To escape these assumptions we turn to utopian fiction. We explore depictions of work in Cokaygne, a utopian tradition dating back to the 12th century, and William Morris's 19th century News from Nowhere. Cokaygne is a land of excessive consumption without work, while in News from Nowhere work is the route to the good life. These competing notions provide inspiration for a post-growth vision of work. We argue that biophysical and social dynamics mean that in a post-growth economy we are likely to have to be less productive and work more. But, this can be a utopian vision. By breaking the link between work and consumption at the level of the individual, we can remove some of the coercion in work. This would free us to do jobs that contribute to the social good, rather than generate exchange value, and empower us to fight for good work. Finally, we draw on eco-feminist analyses of capitalism to argue that by challenging labour productivity growth we can also challenge wider forces of oppression
Fairness and Globalisation in the Western European Clothing Supply Chain
No full textNoIn this chapter we use global multi-regional input-output analysis to explore how globalisation has impacted fairness along Western European clothing supply chains. Our analysis shows that while globalisation has made the Western European clothing supply chain ‘fairer’ by increasing employment opportunities and income for workers in Brazil, Russia, India and China (BRIC), it has failed to make the supply chain fair. Despite large increases in the labour compensation received by BRIC workers in the Western European clothing supply chain, labour compensation is still insufficient to support a decent standard of living and cannot, therefore, be considered fair
Lockdown and Sustainability: An Effective Model of Information and Communication Technology
Get PDFYesCovid-19, a corona virus, has maintained its momentum in spreading among communities. In this context of social crisis, this study seeks to identify the reasons for the partial failure to fulfill the intended goal of lockdown, and to formulate an inclusive behavioral model reflecting comprehensive human behavior and social psychology. In order to answer the research questions, this study has conducted extensive interviews among individuals who were targets of the lockdown system. From this exploratory and qualitative investigation, researchers have recognized four paradigms as the key to understanding human behavior and social psychology in violating lockdown as a social isolation system during this period of crisis. The identified parameters depicting social behavior are: Derogation and Argument (SDA), Tangible Need and Deficiency (TND), Intangible Desire and Expectancy (IDE), and Evaluation of Benefit and Loss (UBL). Finally, as a comprehensive guideline, a grounded theory of the social behavior ‘paradigm for lockdown violation (PLV)’ is explored as the reason for the violation of the social system
Clinical procedures in primary eye care
No full textNoFrom the publisher - Well organized and easy to read, Clinical Procedures in Primary Eye Care, 5th Edition, takes an accessible, step-by-step approach to describing the commonly used primary care procedures that facilitate accurate diagnosis and effective patient management. This practical, clinically-focused text offers succinct descriptions of today's most frequently encountered optometric techniques supported by research-based evidence. You’ll find essential instructions for mastering the procedures you need to know, including recent technical advances in the field
Experiences following cataract surgery – patient perspectives
Get PDFYesPurpose: Most patients report being highly satisfied with the outcome of cataract surgery but there are variable reports regarding the impact of cataract surgery on some real-world activities, such as fall rates. We hypothesised that adaptations to changed refractive correction and visual function may cause difficulties in undertaking everyday activities for some patients and used a series of focus groups to explore this issue. Method: Qualitative methods were used to explore patients’ experiences of their vision following cataract surgery, including adaptation to vision changes and their post-surgical spectacle prescription. Twenty-six participants took part in five focus groups (Mean age = 68.2 ± 11.4 years), and the data were analysed using thematic analysis. Results: We identified three themes. ‘Changes to Vision’ explores participants’ adaptation following cataract surgery. While several had problems with tasks relying on binocular vision, few found them bothersome and they resolved following second eye surgery. Participants described a trial and error approach to solving these problems rather than applying solutions suggested by their eyecare professionals. ‘Prescription Restrictions’ describes the long-term vision problems that pre-surgery myopic patients experienced as a consequence of becoming emmetropic following surgery and thus needing spectacles for reading and other close work activities, which they did not need before surgery. Very few reported that they had the information or time to make a decision regarding their post-operative correction. ‘Information Needs’ describes participant’s responses to the post-surgical information they were given, and the unmet information need regarding when they can drive following surgery. Conclusion: The findings highlight the need for clinicians to provide information on adaptation effects, assist patients to select the refractive outcome that best suits their lifestyle, and provide clear advice about when patients can start driving again. Patients need to be provided with better guidance from clinicians and prescribing guidelines for clinicians would be beneficial, particularly for the period between first- and second-eye surgery.Dunhill Medical Trust. Grant Number: RTF1806/53
Point-of-care lactate measurement for suspected sepsis in the prehospital environment: are we missing the point at the sharp end?
No full textNoExpecting ambulance clinicians to dependably differentiate the life-threatening organ dysfunction caused by sepsis from an inflammatory response to a non-infectious aetiology, relying upon vital signs and a physical examination of the patient alone, must be considered unrealistic. Although lactate measurement has been integrated into numerous prehospital sepsis screening tools, it is not yet measured routinely within UK ambulance services. Research has generally focused on whether handheld point-of-care lactate measurement devices are as accurate as laboratory analysis of venous or arterial samples. The weight of literature has concluded negatively in relation to this. However, there is potential for handheld devices to be used independently to monitor trends in lactate elimination or accumulation to inform decisions on the efficacy of prehospital interventions, or simply to report categorical data in terms of whether lactate levels are elevated or not. This offers UK paramedics the opportunity to improve sepsis care through the enhanced assessment of risk and acuity, the identification of patients with cryptic shock, more aggressive fluid resuscitation and advanced notification to receiving units
AOA localization for vehicle-tracking systems using a dual-band sensor array
Get PDFYesThe issue of asset tracking in dense environments where the performance of the global positioning system (GPS) becomes unavailable or unreliable is addressed. The proposed solution uses a low-profile array of antenna elements (sensors) mounted on a finite conducting ground. A compact-size sensor array of six electrically small dual-band omnidirectional spiral antenna elements was designed as a front end of a tracker to operate in the 402 and 837 MHz spectrum bands. For the lower band, a three-element superposition method is applied to support estimation of the angle of arrival (AOA), whereas all six sensors are employed for the higher band. A low complexity and accurate AOA determination algorithm is proposed, the projection vector (PV), and this is combined with the array mentioned. Orthogonal frequency division multiplexing (OFDM) is integrated with the PV technique to increase the estimation resolution. The system was found to be suitable for installation on the roof of vehicles to localize the position of assets. The proposed system was tested for the tracking of nonstationary sources, and then two scenarios were investigated using propagation modeling software: outdoor to outdoor and outdoor to indoor. The results confirm that the proposed tracking system works efficiently with a single snapshot.European Union Horizon 2020 Research and Innovation Program; 10.13039/501100009928 - Higher Committee for Education Development (HCED), Ira
Solid-State Competitive Destabilization of Caffeine Malonic Acid cocrystal: Mechanistic and Kinetic Investigation
Get PDFYesThe main objective of this research is to investigate solid-state destabilization mechanism and kinetics of the model cocrystal caffeine : malonic acid (CA:MO) in presence of oxalic acid (OX) as a structural competitor. Competitive destabilization of CA:MO and subsequent formation of CA:OX takes place at temperatures significantly below its melting point. Destabilization mechanism was found to be mediated by sublimation of both CA:MO and OX. During CA:MO destabilization, free CA could not be detected and direct transformation to CA:OX cocrystal was observed. The destabilization kinetics follow Prout-Tompkins nucleation and crystal growth model with activation energy of 133.91 kJ/mol and subsequent CA:OX growth kinetic follow Ginstling – Brounshtien diffusion model with activation energy of kJ/mol