Continuous flow synthesis and simulation-supported investigation of tunable plasmonic gold patchy nanoparticles.

Plasmonic nanoparticles have intriguing optical properties which make them suitable candidates for sensing or theranostic applications. Anisotropic patchy particles, where metal is locally deposited on the surface of a core particle, exhibit plasmon resonances that can be specifically adjusted for these applications. However, many existing synthesis routes are complex, yield too little material, or provide particles with limited optical tunability. In this work, we present a simple and scalable continuous flow synthesis of gold-on-polystyrene patchy particles with widely adjustable optical properties. By increasing the chloride concentration in the electroless deposition of gold, we slow down the redox reduction kinetics and obtain a dense patch morphology as well as a reduced nucleation rate. The latter is counteracted by introducing a low-level seeding approach where a small number of gold nanocrystals heterocoagulate with the core particles prior to patch growth. Seeding and patch growth are performed in a continuous flow set-up with two T-shaped milli-mixers. The resulting patchy particle samples exhibit a tunable dipolar plasmon peak between 600 nm and 1100 nm. We also investigate the structure-property relationship for our gold patchy particles using finite element method simulations. After identifying a suitable patch shape model, we elucidate the influence of individual geometric parameters on the optical properties and show that the relationship holds true for a large range of patch coverages. Finally, we apply the relationship to explain the time-dependent change in the optical properties of as-synthesized patches by correlating it with the patch shape transformation revealed by electron microscopy.

Oculomics: A Crusade Against the Four Horsemen of Chronic Disease.

Chronic, non-communicable diseases present a major barrier to living a long and healthy life. In many cases, early diagnosis can facilitate prevention, monitoring, and treatment efforts, improving patient outcomes. There is therefore a critical need to make screening techniques as accessible, unintimidating, and cost-effective as possible. The association between ocular biomarkers and systemic health and disease (oculomics) presents an attractive opportunity for detection of systemic diseases, as ophthalmic techniques are often relatively low-cost, fast, and non-invasive. In this review, we highlight the key associations between structural biomarkers in the eye and the four globally leading causes of morbidity and mortality: cardiovascular disease, cancer, neurodegenerative disease, and metabolic disease. We observe that neurodegenerative disease is a particularly promising target for oculomics, with biomarkers detected in multiple ocular structures. Cardiovascular disease biomarkers are present in the choroid, retinal vasculature, and retinal nerve fiber layer, and metabolic disease biomarkers are present in the eyelid, tear fluid, lens, and retinal vasculature. In contrast, only the tear fluid emerged as a promising ocular target for the detection of cancer. The retina is a rich source of oculomics data, the analysis of which has been enhanced by artificial intelligence-based tools. Although not all biomarkers are disease-specific, limiting their current diagnostic utility, future oculomics research will likely benefit from combining data from various structures to improve specificity, as well as active design, development, and optimization of instruments that target specific disease signatures, thus facilitating differential diagnoses.

Long-term diseases can stop people living long and healthy lives. In many cases, early diagnosis can help to prevent, monitor, and treat disease, which can improve patients' health. In order to diagnose disease, we need tools that are easy for patients to access, painless, and low-cost. The eye may provide the solution. In this review, we discuss the link between changes in the eye and four types of long-term disease that, together, kill most of the population: (1) Cardiovascular disease (affecting the heart and/or blood). (2) Cancer (abnormal growth of cells). (3) Neurodegenerative disease (affecting the brain and/or nervous system). (4) Metabolic disease (problems storing, accessing, and using the body's fuel). We show that neurodegenerative disease leaves tell-tale signs in lots of different parts of the eye. Signs of cardiovascular and metabolic disease biomarkers are mostly found in the back of the eye, and signs of cancer can be found in the tear fluid. Although signs of disease can be seen in the eye, not all of them will tell us what the disease is. We believe that future research will help us to understand more about long-term disease and how to detect it if we combine information from different structures within the eye and develop new tools to target these specific structures.

Out-of-hours decision-making in deteriorating patients by foundation year doctors: Relationship to moral distress.

BACKGROUND: Moral distress (MD) refers to psychological unease when healthcare professionals identify morally correct actions to take but are constrained in their ability to take those actions. METHODS: This study evaluated the relationship between out-of-hours decisions and MD among 40 Foundation Year 2 (FY2) doctors. They were asked to choose the 'expected' and the 'right' management options for five out-of-hours scenarios and complete an adapted Measure of Moral Distress for Health Professionals (MMD-HP) questionnaire. RESULTS: 28/40 (70%) reported discordance between 'expected' and 'right' options more frequently than concordance. The mean total MMD-HP score was low: 64.9 (SD = 26.9), range 13-143, maximum 288. The association between decision-making discordance and MMD-HP score was weak. CONCLUSION: Out-of-hours decisions by FY2 doctors were characterised by doing what is 'expected' rather than what is perceived to be 'right'. Providing guidance regarding decision-making in deteriorating patients is needed for patient safety and staff well-being.

Cardio-vocal syndrome - How 'benign' condition can turn 'malignant'?

Cardio-vocal syndrome (also called as Ortner's syndrome) is hoarseness of voice due to compression of left recurrent laryngeal nerve secondary to enlarged cardiac chambers and structures. We present two cases of Ortner's syndrome secondary to atrial fibrillation causing enlargement of left atrium compressing the left recurrent laryngeal nerve, and their clinical outcomes.

Contemporary pedagogy? The use of theory in practice: An evidence-informed perspective.

Utilizing cognitive psychology as a foundation, this paper offers a deeper consideration of contemporary theoretical influences on coaching pedagogy. Countering recent dichotomies suggested between pedagogic approaches, we reintroduce key findings from the cognitive tradition and their implications for practice which coaches may find useful. Using cognitive load, novice and expert differences, desirable difficulty, and fidelity, we suggest that the lines drawn between different "pedagogies" may not be as sharp as suggested. Instead, we suggest that coaches avoid defining themselves as being aligned to a specific pedagogical or paradigmatic stance. We conclude by advocating for research informed practice, absent of strict theoretical boundaries and instead, considering contemporary pedagogy as drawing on the needs of the context, the experience of the coach and the best available evidence.

Older adults and non-response to rabies post-exposure prophylaxis: Challenges and approaches.

Rabies vaccines are highly effective and immunogenic in most populations, including when used as rabies post-exposure prophylaxis (RPEP); however, there is mounting evidence that the immune response to rabies vaccines, though predicted to be adequate, may be lower in older adults. Despite this, there are no specific recommendations in Canadian guidance to monitor the serological response of older adults following RPEP. Furthermore, while Canadian guidance recommends the intramuscular route for RPEP vaccination, there is good evidence supporting the immunogenicity, effectiveness and safety of RPEP vaccination using the intradermal route. We present a case of an 87-year-old male with rabies exposure who failed to respond to two series of RPEP with intramuscular rabies vaccination but responded to a third series using intradermal vaccine administration and provide reasoning for subsequent management. This case is brought forward to prompt discussion and research as to the utility of completing serology in older adults receiving RPEP as well as vaccination strategies, including route of administration, in those who do not respond to an initial course of RPEP vaccination.

Strategy in talent systems: Top-down and bottom-up approaches.

Building on a large volume of recent research in talent identification and development, this paper future directions for research and practice. We suggest that strategic coherence become a greater point of emphasis in both, with the Performance, Outcome and Process framework holding the potential to signal various markers of effectiveness. Secondly, greater recognition of the need to deploy limited resources where they promote movement toward these markers of effectiveness. Finally, we make recommendations for the operationalising of strategy in talent and performance systems by considering the integration of top down and bottom-up strategic processes.

Molecular Dynamics Study of the Aggregation Behavior of N,N,N',N'-Tetraoctyl Diglycolamide.

Liquid-liquid extraction is a commonly used technique to separate metals and is a process that has particular relevance to the nuclear industry. There has been a drive to use environmentally friendly ligands composed only of carbon, hydrogen, nitrogen, and oxygen. One example is the i-SANEX process that has been developed to separate minor actinides from spent nuclear fuel. The underlying science of such processes, is, however, both complex and intriguing. Recent research indicates that the liquid phases involved are frequently structured fluids with a hierarchical organization of aggregates. Effective flow-sheet modeling of such processes is likely to benefit from the knowledge of the fundamental properties of these phases. As a stepping stone toward this, we have performed molecular dynamics simulations on a metal free i-SANEX system composed of the ligand N,N,N',N'-tetraoctyl diglycolamide (TODGA), diluent hydrogenated tetrapropylene (TPH), and polar species water and nitric acid. We have also studied the effects of adding n-octanol and swapping TPH for n-dodecane. It would seem sensible to understand this simpler system before introducing metal complexes. Such an understanding would ideally arise from studying the system's properties over a wide range of compositions. The large number of components, however, precludes a comprehensive scan of compositions, so we have chosen to study a fixed concentration of TODGA while varying the concentrations of water and nitric acid over a substantial range. Reverse aggregates are observed, with polar species in the interior in contact with the polar portions of the TODGA molecules and the organic diluent on the exterior in contact with the TODGA alkyl chains. These aggregates are irregular in shape and grow in size as the amount of water and nitric acid increases. At a sufficiently high polar content, a single extended cluster forms corresponding to the third phase formation. No well-defined bonding motifs were observed between the polar species and TODGA. The cluster size distribution fits an isodesmic model, where the Gibbs energy change of adding a TODGA molecule to a cluster ranges between 4.5 and 7.0 kJ mol-1, depending on the system composition. The addition of n-octanol was found to reduce the degree of aggregation, with n-octanol acting as a co-surfactant. Exchanging the diluent TPH for n-dodecane also decreased the aggregation. We present evidence that this is due to the greater penetration of n-dodecane into the reverse aggregates. It is known, however, that the propensity for the third phase formation is greater with n-dodecane as the diluent than is the case with TPH, but we argue that these two results are not contradictory. This research casts light on the driving forces for aggregation, informs process engineers as to what species are present, and indicates that flow-sheet liquid-liquid extraction modeling might benefit by incorporating an isodesmic aggregation approach.

Sustainability and Justice: Challenges and Opportunities for an Open STEM Education.

Open educational resources, or OER, are teaching materials that reside in the public domain and are available under an open license. While the creation of high-quality materials and cyberinfrastructure to share these resources is important, OER are much more than static resource repositories. Vibrant OER communities function as collaboration hubs and often include librarians, instructional technologists, instructors, education researchers, funders, open-source software developers, and college administrators. Together, these individuals work as a community to respond to changes in the education landscape, support student learning impacts both in terms of cost savings and student retention, and solve issues related to broadly sharing open resources on the web. This essay provides general information about OER, describes communities developing OER for science, technology, engineering, and mathematics education, and presents insights about sustainability challenges. The sustainability challenges are organized according to multiple dimensions: cultural and social, economic and financial, and technological and environmental. In addition, OER provide important opportunities to address and promote social justice and open and accessible education philosophies. Knowing more about the OER landscape, sustainability challenges, and educational justice opportunities can help instructors use and contribute to this growing movement to reshape the landscape of undergraduate education.

Evaluation of a Standardized Tacrolimus Therapeutic Drug Monitoring Protocol in Stable Kidney Transplant Recipients.

Introduction: Transplant nurse coordinators have assisted in accurately adjusting tacrolimus doses under a collaborative practice agreement for kidney transplant recipients in the early post-operative period. This study evaluated the efficiency of a standardized tacrolimus therapeutic drug monitoring (TDM) protocol in stable outpatient recipients. Design: We conducted a single-center, retrospective study of adult patients who received a kidney transplant at least 3 years ago and were taking immediate-release tacrolimus. Before September 2019, transplant coordinators consulted transplant providers for management of all tacrolimus trough levels (Pre-Arm). Under the standardized protocol, coordinators directly responded to out-of-range tacrolimus trough levels (Post-Arm). The primary outcome was the time to intervention for out-of-range levels. Secondary outcomes included adverse events, time in therapeutic range, coefficient of variation (CV), and protocol compliance. Results: Of 1712 levels (from 174 patients), 259 levels (15.1%) were out-of-range. The overall time to intervention was 13.2 hours shorter (95% CI: -26.4 to -0.1 hours; P = 0.048) in the Post-Arm. There was no rejection, graft loss, or death during the study period. The time in therapeutic range was 89.3% (17.6%) vs 89% (19.4%; P = 0.816) and CV was 19.7% (15.8%) vs 18.4 (10.7%; P = 0.358) in the Pre-Arm and Post-Arm, respectively. Within the Post-Arm, the protocol required coordinators to independently intervene on 96 out-of-range levels (65.8%), which were accurately addressed 57.5% of the time. Conclusion: Implementation of a standardized TDM protocol improved efficiency without compromising major clinical outcomes or intrapatient variability (IPV) of tacrolimus levels for stable kidney recipients in the outpatient setting.

Myocardial Fibrosis Predicts Ventricular Arrhythmias and Sudden Death After Cardiac Electronic Device Implantation.

BACKGROUND: Increasing evidence supports a link between myocardial fibrosis (MF) and ventricular arrhythmias. OBJECTIVES: The purpose of this study was to determine whether presence of myocardial fibrosis on visual assessment (MFVA) and gray zone fibrosis (GZF) mass predicts sudden cardiac death (SCD) and ventricular fibrillation/sustained ventricular tachycardia after cardiac implantable electronic device (CIED) implantation. METHODS: In this prospective study, total fibrosis and GZF mass, quantified using cardiovascular magnetic resonance, was assessed in relation to the primary endpoint of SCD and the secondary, arrhythmic endpoint of SCD or ventricular arrhythmias after CIED implantation. RESULTS: Among 700 patients (age 68.0 ± 12.0 years), 27 (3.85%) experienced a SCD and 121 (17.3%) met the arrhythmic endpoint over median 6.93 years (IQR: 5.82-9.32 years). MFVA predicted SCD (HR: 26.3; 95% CI: 3.7-3,337; negative predictive value: 100%). In competing risk analyses, MFVA also predicted the arrhythmic endpoint (subdistribution HR: 19.9; 95% CI: 6.4-61.9; negative predictive value: 98.6%). Compared with no MFVA, a GZF mass measured with the 5SD method (GZF5SD) >17 g was associated with highest risk of SCD (HR: 44.6; 95% CI: 6.12-5,685) and the arrhythmic endpoint (subdistribution HR: 30.3; 95% CI: 9.6-95.8). Adding GZF5SD mass to MFVA led to reclassification of 39% for SCD and 50.2% for the arrhythmic endpoint. In contrast, LVEF did not predict either endpoint. CONCLUSIONS: In CIED recipients, MFVA excluded patients at risk of SCD and virtually excluded ventricular arrhythmias. Quantified GZF5SD mass added predictive value in relation to SCD and the arrhythmic endpoint.

Determination of the yield, mass and structure of silver patches on colloidal silica using multiwavelength analytical ultracentrifugation.

Anisotropic nanoparticles offer considerable promise for applications but also present significant challenges in terms of their characterization. Recent developments in the electroless deposition of silver patches directly onto colloidal silica particles have opened up a simple and scalable synthesis method for patchy particles with tunable optical properties. Due to the reliance on patch nucleation and growth, however, the resulting coatings are distributed in coverage and thickness and some core particles remain uncoated. To support process optimization, new methods are required to rapidly determine patch yield, thickness and coverage. Here we present a novel approach based on multiwavelength analytical ultracentrifugation (MWL-AUC) which permits simultaneous hydrodynamic and spectroscopic characterization. The patchy particle colloids are produced in a continuous flow mixing process that makes use of a KM-type micromixer. By varying the process flow rate or metal precursor concentration we show how the silver to silica mass ratio distribution derived from the AUC-measured sedimentation coefficient distribution can be influenced. Moreover, through reasoned assumptions we arrive at an estimation of the patch yield that is close to that determined by arduous analysis of scanning electron microscopy (SEM) images. Finally, combining MWL-AUC, electrodynamic simulations and SEM image analysis we establish a procedure to estimate the patch thickness and coverage.

Tissue cryopreservation using the 3M™ Novec™ 7000 freezing coolant offers a comparable and safe alternative to customary coolants.

Cryopreserving tissues for histology requires the use of coolants to buffer the sample from liquid nitrogen (LN2) and to control the rate of temperature decline. Several coolants sharing similar physical characteristics are available on the market; however, commonly used coolants are variably flammable and/or toxic and pose risks to personnel and facilities. The purpose of this study was to compare the performance of three commercially available coolants: hexane, 2-methylbutane (2 M), and 1-methoxyheptafluoropropane (N7000). Fresh mouse tissues were frozen by each method, for their ability to preserve microscopic architecture and to protect RNA from degradation were evaluated and compared to tissue characteristics obtained by direct immersion in LN2. Our results show that for most tissues, the N7000 freezing coolant provides equal or improved preservation of microscopic architecture. While snap-freezing tissues in LN2 provides superior RNA protection, no significant differences in RNA quality were seen between tissues frozen in hexane, 2 M, and N7000.

The Role of Siblings in Talent Development: Implications for Sport Psychologists and Coaches.

Developing talent requires consideration of social networks that can facilitate or inhibit progression. Of fundamental influence in this regard is the family, with recent investigation extending its focus from parents to the role of siblings. As such, the purpose of this Conceptual Analysis article is to, firstly, review the characteristics of the sibling relationship that may support or inhibit talent development. Secondly, the analysis then provides empirically derived practical examples to emphasize the holistic and complex role that siblings can play in talent development. Thirdly, strategies are proposed to support practitioners identify specific sibling characteristics, alongside recommendations for how the relationship can be utilized within both the formal and informal environments by coaches and psychologists. Finally, and crucially, important implications of these characteristics are considered to support effective coach and sport psychologist decision making.

Pain during cardiac implantable electronic device implantation.

In order to evaluate the extent and causes of pain during cardiac implantable electronic device (CIED) implantation in our hospital, a prospective audit over a 23-month period using a patient selfreporting questionnaire was undertaken. In total, 599 procedures were reported, 52.9% for de novo pacemaker implantation and 23.4% for high-energy devices (cardiac resynchronisation therapy defibrillator [CRT-D], implantable cardiac defibrillator [ICD], subcutaneous ICD). Overall, the median pain score was 2/10 (interquartile range 2-4). In total, 61.6% (367/599) reported no pain or mild pain (pain scores 0-3/10), 27.7% (165/599) reported moderate pain (pain score of 4-6/10) and 10.7% (64/599) reported severe pain (pain score of 7-10/10) during the procedure. Significant preimplant worry (odds ratio [OR] 2.13, 95% confidence interval [CI] 1.22 to 3.73) and higher lidocaine doses (OR 1.06, 95%CI 1.00 to 1.11) were associated with severe patient-reported pain. In conclusion, most patients underwent CIED implantation with minimum stress and maximum comfort. An important minority reported severe pain during the procedure. Optimising surgical technique and interventions targeted at reducing pre- and peri-implant worry, particularly in women, and especially in those receiving ICDs, warrants further investigation to reduce patient-reported pain during CIED implantation.

Identification of Noncompetitive Protein-Ligand Interactions for Structural Optimization.

For efficient structure-guided drug design, it is important to have an excellent understanding of the quality of interactions between the target receptor and bound ligands. Identification and characterization of poor intermolecular contacts offers the possibility to focus design efforts directly on ligand regions with suboptimal molecular recognition. To enable a more straightforward identification of these in a structural model, we use a suitably enhanced version of our previously introduced statistical ratio of frequencies (RF) approach. This allows us to highlight protein-ligand interactions and geometries that occur much less often in the Protein Data Bank than would be expected from the exposed surface areas of the interacting atoms. We provide a comprehensive overview of such noncompetitive interactions and geometries for a set of common ligand substituents. Through retrospective case studies on congeneric series and single-point mutations for several pharmaceutical targets, we illustrate how knowledge of noncompetitive interactions could be exploited in the drug design process.

Identifying and characterizing translationally modulated molecular crystal structures.

Most structural (i.e. displacive) modulations make molecules independent that had been related by translation in a phase having a smaller or centered unit cell. In the modulated structure the independent molecules are differentiated by small translations, rotations, and/or conformational changes but an approximate translational relationship is normally retained. A program has been written to identify such pseudotranslations because they can be difficult to find by eye and because they combine with each other and with lattice translations in ways that can be confusing. To characterize the pseudotranslations the program calculates their fractional translational, orientational, and conformational components as well as several quality indicators. While many pseudotranslations are obvious, others are borderline; setting tolerances for identifying a pseudotranslation proved difficult. Defaults were chosen to reproduce experience-based judgment but they can be varied in the program input. The program was run for organic and for metallo-organic structures with R ≤ 0.075 in the 2019 release of the Cambridge Structural Database. The frequency of pseudotranslations increases with Z' and is approximately 50% for Z' > 4. Some structures were found in which an identified pseudotranslation cannot correspond to a modulation. These include structures in which some but not all of the molecules are related by pseudotranslations and structures in which pseudotranslations in different parts of the unit cell have different directions.

Development of the BioCalculus Assessment (BCA).

We describe the development and initial validity assessment of the 20-item BioCalculus Assessment (BCA), with the objective of comparing undergraduate life science students' understanding of calculus concepts in different courses with alternative emphases (with and without focus on biological applications). The development process of the BCA included obtaining input from a large network of scientists and educators as well as students in calculus and biocalculus courses to accumulate evidential support of the instrument's content validity and response processes of test takers. We used the Rasch model to examine the internal structure of scores from students who have experienced calculus instruction in the two methods. The analysis involved three populations (Calculus 1, Calculus 2, and Biocalculus) for which the Calc 1 and Calc 2 students were not exposed to calculus concepts in a life science setting, while the Biocalculus students were presented concepts explicitly with a life science emphasis. Overall, our findings indicate that the BCA has reasonable validity properties, providing a diagnostic tool to assess the relative learning success and calculus comprehension of undergraduate biology majors from alternative methods of instruction that do or do not emphasize life science examples.

How Significant Are Unusual Protein-Ligand Interactions? Insights from Database Mining.

We present a new approach to derive interaction propensities of protein-ligand atom pairs from mining of the Protein Data Bank. To ensure solid statistics, we use a line-of-sight contact filter and normalize the observed frequency of hits by a statistical null model based on exposed surface areas of atom types in the protein-ligand binding site. This allows us to investigate which intermolecular interactions and geometries are found more often than expected by chance in protein-ligand complexes. We focus our study on some of the unusual interactions that were postulated to be favorable, including σ-hole bonding of halogen and sulfur atoms, weak hydrogen bonding with fluorine as acceptor, and different types of dipolar interactions. Our results confirm some and challenge other common assumptions on these interactions and highlight other contact types that are yet underexplored in structure-based drug design.

Thermal Processing of Chloride-Contaminated Plutonium Dioxide.

Over 80 heat treatment experiments have been made on samples of chloride-contaminated plutonium dioxide retrieved from two packages in storage at Sellafield. These packages dated from 1974 and 1980 and were produced in a batch process by conversion of plutonium oxalate in a furnace at around 550 °C. The storage package contained a poly(vinyl chloride) (PVC) bag between the screw top inner and outer metal cans. Degradation of the PVC has led to adsorption of hydrogen chloride together with other atmospheric gases onto the PuO2 surface. Analysis by caustic leaching and ion chromatography gave chloride contents of ∼2000 to >5000 ppm Cl (i.e., µgCl g-1 of the original sample). Although there are some subtle differences, in general, there is surprisingly good agreement in results from heat treatment experiments for all the samples from both cans. Mass loss on heating (LOH) plateaus at nearly 3 wt % above 700 °C, although samples that were long stored under an air atmosphere or preexposed to 95% relative humidity atmospheres, gave higher LOH up to ∼4 wt %. The majority of the mass loss is due to adsorbed water and other atmospheric gases rather than chloride. Heating volatilizes chloride only above ∼400 °C implying that simple physisorption of HCl is not the main cause of contamination. Interestingly, above 700 °C, >100% of the initial leachable chloride can be volatilized. Surface (leachable) chloride decreases quickly with heat treatment temperatures up to ∼600 °C but only slowly above this temperature. Storage in air atmosphere post-heat treatment apparently leads to a reequilibration as leachable chloride increases. The presence of a "nonleachable" form of chloride was thus inferred and subsequently confirmed in PuO2 samples (pre- and post-heat treatment) that were fully dissolved and analyzed for the total chloride inventory. Reheating samples in either air or argon at temperatures up to the first heat treatment temperature did not volatilize significant amounts of additional chloride. With regard to a thermal stabilization process, heat treatment in flowing air at 800 °C with cooling and packaging under dry argon appears optimal, particularly, if thinner powder beds can be maintained. From electron microscopy, heat treatment appeared to have the most effect on degrading the square platelet particles compared to those with the trapezoidal morphology.