Imagine images for formative assessment

There are many complex concepts and theories that students need to navigate throughout a chemistry course. Often the priority is to memorize facts and algorithms to pass exams rather than developing an adequate understanding. Students can also bring creative alternative conceptions, which hinder further learning. Visualization of the ideas behind chemical processes helps to effectively evaluate and learn concepts. Examples include Einstein’s ‘Elevator’ and Heisenberg’s gamma ray microscope. “A picture tells a thousand words”, graphics are therefore a powerful tool to facilitate understanding of concepts. Presented are examples of graphics for formative assessment supporting exam revision

A Template for Sustainability Education in Chemistry

Solving sustainability as described by the United Nations Sustainable Development Goals, is an important focus of chemistry research. Sustainability education must encompass the complexity and interdisciplinary nature of sustainability problem solving and its impact. Tools of systems thinking, network science, and graph theory are ideal for developing sustainability education exercises and delivering transformative learning, which in turn is essential for advising policy and law makers. [1] A template for sustainability education in chemistry that readily fits into any part of the core chemistry curricula and wider STEM subjects, makes it easy for educators to include sustainability in their courses. In new STEM degree courses, the meaning of sustainability should be covered before the core subject material. [2] Education activities should therefore start by addressing students understanding of sustainability. Current practice in sustainability education and surveys of student, researcher and academic staff understanding of sustainability guide activity development. In groups, students iteratively create concept and system maps alongside discussions led by both the students and educators. Templates of network models and graphics, then show students how to effectively focus problem definitions and form simpler paths through complex information. The models and graphics with summary descriptions directly link specific core chemistry principles to sustainability problem solving. They can be applied at any level of an undergraduate and post graduate degree programme. The sustainability education in chemistry template is presented through examples of (i) first year undergraduate physical chemistry of gas diffusion and (ii) third year undergraduate interdisciplinary chemistry of carbon capture, utilisation and storage (CCUS). Samples of undergraduate, postgraduate, researcher and academic staff review the activities, providing early feedback on how these might enable future generations to play a crucial role in transforming sustainable use of resources. [1] Flynn, A.B., Orgill M. K., Ho F.M., York S., Matlin S.A., Constable D.J.C and Mahaffy P.G. 2019, Future Directions for Systems thinking, J.Chem. Ed., 96, 3000 – 3005. [2] Zuin V.G., Eilks I., Elschami Myriam and Kummerer, 2021, Education in green chemistry and in sustainable chemistry: perspectives toward sustainability, Green Chemistry, 23, 1594

From Characterisation to Validation: A Journey through Master’s Level Analytical Chemistry

The master’s degree in Applied Analytical Chemistry at University College London (UCL) includes valuable teaching input from the UK National Measurement Laboratory for Chemical and Bio-Measurement hosted at LGC. The course starts by introducing accuracy, sensitivity, specificity, trueness, and precision for validating analytical chemistry measurement methods. The principles of proficiency tests, quality control, ruggedness, and associated statistics are practiced using a wide variety of case studies

Dispersion of VOC vapours in the surface treatment workspace: influence of variability in diffusivity, mass transfer and air velocity.

Wherever solvents are allowed to disperse into the workspace it is necessary to be able to predict and determine their concentration and the effect of air velocity variations. Models developed to predict dispersion for assessing ventilation efficiency and worker exposure are validated against measured data with varying success. In numerical convection–dispersion models, including computational fluid dynamics methods, the transport coefficient effective diffusivity is used as a turbulence closure parameter and air velocities are used to define convective mass transport. This study shows how transport coefficient values, empirically estimated from airborne volatile organic carbon vapour concentrations from a solvent source, vary in a ventilated workspace. Variability in effective diffusivity values demonstrates non-Fickian dispersion from the source along the length of a one-dimensional axis. An important finding was that a correlation between air velocity and vapour transport data was not found. This suggests that air velocity should not be used a priori to represent mass transport in the determination of vapour dispersion in the workplace

Combined MR direct thrombus imaging and non-contrast magnetic resonance venography reveal the evolution of deep vein thrombosis: a feasibility study.

OBJECTIVES: Lower limb deep venous thrombosis (DVT) is a common condition with high morbidity and mortality. The aim of the study was to investigate the temporal evolution of the acute thrombus by magnetic resonance imaging (MRI) and its relationship to venous recanalization in patients with recurrent DVTs. METHODS: Thirteen patients with newly diagnosed lower limb DVTs underwent MRI with non-contrast MR venography (NC-MRV) and MR direct thrombus imaging (MR-DTI), an inversion-recovery water-selective fast gradient-echo acquisition. Imaging was performed within 7 days of the acute thrombotic event, then at 3 and 6 months. RESULTS: By 3 months from the thrombotic event a third of the thrombi had resolved and by 6 months about half of the cases had resolved on the basis of vein recanalisation using NC-MRV. On the initial MR-DTI acute thrombus was clearly depicted by hyperintense signal, while the remaining thrombi were predominantly low signal at 3 and 6 months. Some residual thrombi contained small and fragmented persisting hyperintense areas at 3 months, clearing almost completely by 6 months. CONCLUSIONS: Our study suggests that synergistic venous assessment with combined NC-MRV and MR-DTI is able to distinguish acute venous thrombosis from the established (old) or evolving DVT detected by ultrasound. KEY POINTS: • MRI can distinguish between acute and evolving or chronic lower limb DVT • Two advanced MRI techniques can follow the evolution of lower limb DVT • MRI could be used to avoid an incorrect diagnosis of recurrent DVT • MRI could help avoid the risks and complications of lifelong anticoagulation therapy.National Institute for Health Research, Addenbrooke’s Charitable TrustThis is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00330-016-4555-

2-Dimensional ultra-high performance liquid chromatography and DMT-MM derivatization paired with tandem mass spectrometry for comprehensive serum N-glycome characterization.

Glycosylation is a prominent co- and post-translational modification which contributes to a variety of important biological functions. Protein glycosylation characteristics, particularly N-glycosylation, are influenced by changes in one's pathological state, such as through the presence of disease, and as such, there is great interest in N-glycans as potential disease biomarkers. Human serum is an attractive source for N-glycan based biomarker studies as circulatory proteins are representative of one's physiology, with many serum proteins containing N-glycosylation. The difficulty in comprehensively characterizing the serum N-glycome arises from the absence of a biosynthetic template resulting in great structural heterogeneity and complexity. To help overcome these challenges we developed a 2-dimensional liquid chromatography platform which utilizes offline weak anion exchange (WAX) chromatography in the first dimension and hydrophilic interaction liquid chromatography (HILIC) in the second dimension to separate N-glycans by charge, corresponding to degree of sialylation, and size, respectively. Performing these separations offline enables subsequent derivatization with 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) for sialic acid linkage determination and the identification of sialic acid linkage isomers. Subsequent tandem mass spectrometry analysis revealed the identification of 212 complete and partial N-glycan structures including low abundant N-glycans containing acetyl and sulphate modifications. The identifications obtained through this platform were then applied to N-glycans released from a set of stage 3 gastric cancer serum samples obtained from patients before (pre-op) and after (post-op) tumour resection to investigate how the serum N-glycome can facilitate differentiation between the two pathological states

Waiting for coronary revascularization: A comparison between New York State, the Netherlands and Sweden

Objective: To compare waiting times for percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft (CABG) surgery in New York State, the Netherlands and Sweden and to determine whether queuing adversely affects patients' health. Methods: We reviewed the medical records of 4487 chronic stable angina patients who underwent PTCA or CABG in one of 15 New York State hospitals (n = 1021) or were referred for PTCA or CABG to one of ten hospitals in the Netherlands (n = 1980) or to one of seven hospitals in Sweden (n = 1486). We measured the median waiting time between coronary angiography and PTCA or CABG. Results: The median waiting time for PTCA in New York was 13 days compared with 35 and 42 days, respectively, in the Netherlands and Sweden (P<0.001). For CABG, New York patients waited 17 days, while Dutch and Swedish patients waited 72 and 59 days, respectively (P< 0.001). The Swedish and Dutch waiting list mortality rate was 0.8% for CABG candidates and 0.15% for PTCA candidates. Conclusions: There were large variations in waiting time for coronary revascularization among these three sites. Patients waiting for CABG were at greatest risk of experiencing an adverse event. In both the Netherlands and Sweden, the capacity to perform coronary revascularization has been expanded since this study began. Further international cooperation may identify other areas where quality of care can be improved

Prospective study evaluating the relative sensitivity of 18F-NaF PET/CT for detecting skeletal metastases from renal cell carcinoma in comparison to multidetector CT and 99mTc-MDP bone scintigraphy, using an adaptive trial design.

BACKGROUND: The detection of occult bone metastases is a key factor in determining the management of patients with renal cell carcinoma (RCC), especially when curative surgery is considered. This prospective study assessed the sensitivity of (18)F-labelled sodium fluoride in conjunction with positron emission tomography/computed tomography ((18)F-NaF PET/CT) for detecting RCC bone metastases, compared with conventional imaging by bone scintigraphy or CT. PATIENTS AND METHODS: An adaptive two-stage trial design was utilized, which was stopped after the first stage due to statistical efficacy. Ten patients with stage IV RCC and bone metastases were imaged with (18)F-NaF PET/CT and (99m)Tc-labelled methylene diphosphonate ((99m)Tc-MDP) bone scintigraphy including pelvic single photon emission computed tomography (SPECT). Images were reported independently by experienced radiologists and nuclear medicine physicians using a 5-point scoring system. RESULTS: Seventy-seven lesions were diagnosed as malignant: 100% were identified by (18)F-NaF PET/CT, 46% by CT and 29% by bone scintigraphy/SPECT. Standard-of-care imaging with CT and bone scintigraphy identified 65% of the metastases reported by (18)F-NaF PET/CT. On an individual patient basis, (18)F-NaF PET/CT detected more RCC metastases than (99m)Tc-MDP bone scintigraphy/SPECT or CT alone (P = 0.007). The metabolic volumes, mean and maximum standardized uptake values (SUV mean and SUV max) of the malignant lesions were significantly greater than those of the benign lesions (P < 0.001). CONCLUSIONS: (18)F-NaF PET/CT is significantly more sensitive at detecting RCC skeletal metastases than conventional bone scintigraphy or CT. The detection of occult bone metastases could greatly alter patient management, particularly in the context when standard-of-care imaging is negative for skeletal metastases.This work was supported by Cancer Research UK [grant number C19212/A16628]. The authors also received research support from the National Institute of Health Research Cambridge Biomedical Research Centre, Engineering and Physical Sciences Research Council Imaging Centre in Cambridge and Manchester, and the Cambridge Experimental Cancer Medicine Centre. The research has also been partly funded by a generous donation from the family and friends of a patient.This is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/annonc/mdv28

Analysis of Rating Appropriateness and Patient Outcomes in Cataract Surgery

Purpose: Using the RAND/UCLA methodology to create the appropriateness criteria, we assessed that the appropriate ratings in cataract surgery can be a better prognosis of outcomes in postoperative 12 months than uncertain or inappropriate ratings. In addition, we indentified the degree of the appropriate rating surgery associated with the outcome changes in postoperative 12 months. Materials and Methods: The patients in this study were followed up prospectively in preoperative and postoperative 12 months periods. The 20 ophthalmologists in 14 hospitals were asked to refer about 20 patients who were scheduled to undergo cataract surgery from March and June of 1997. A multiple regression analysis was used to identify the degree of the appropriate surgery associated with the changes of outcomes. The outcomes were designed as the clinical and functional outcomes (visual acuity, visual function, satisfaction with vision, and satisfaction with overall care). Results: The outcome changes of vision acuity (p &lt; 0.001), vision function-14 (p &lt; 0.001), and symptom score (p &lt; 0.006) were significantly different between four appropriateness ratings (crucial, appropriate, uncertain, and inappropriate). There was a trend that the appropriate rating surgeries were related to the successful change of the vision function (2.29, p = 0.015) and satisfaction with vision (3.84, p = 0.014) in 12 month postoperative period. Conclusion: The crucial or appropriate rating surgeries may indicate better outcomes than uncertain or inappropriate rating surgeries do. The appropriate rating surgeries were more closely related to functional outcome vision function, VF-14 and subjective outcom