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INTRODUCTION: We aimed to explore the impact of social distancing on the incidence, severity and microbiology of patients with acute tonsillitis (AT). METHODS: In this single-centre study, we retrospectively included all patients with AT referred to the Ear-Nose-Throat Department, Aarhus University Hospital, Denmark, in the two years preceding versus the two years after the COVID-19 lockdown in Denmark (11 March 2020). RESULTS: In total, 425 patients were included. The incidence of AT was significantly lower in the post-lockdown period (n = 128) than in the pre-lockdown period (n = 297) (p less-than 0.001). Reduced incidence was observed across all age groups. No significant differences were found in patient characteristics between periods. The proportion of hospitalised patients was significantly lower in the post- than in the pre-lockdown period (36% versus 25%, p = 0.032). Prevalent culture findings were Streptococcus pyogenes (15%), S. anginosus group (11%) and Fusobacterium necrophorum (5%). No statistically significant differences in the relative prevalence of individual bacteria were found between periods. CONCLUSIONS: The incidence of patients with AT referred to hospital decreased by 57% in the two-year period after the COVID-19 lockdown compared with the period leading up to the lockdown. Our findings suggest that this decrease mirrored a general decline in AT incidence rather than altered referral patterns. FUNDING: None. TRIAL REGISTRATION: The study was approved by the Danish Data Protection Agency (#1-16-02-134-23) and the Danish Patient Safety Authority (#1-45-70-41-23).
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COVID-19 , Tonsilite , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Tonsilite/epidemiologia , Tonsilite/microbiologia , Incidência , Dinamarca/epidemiologia , Feminino , Masculino , Estudos Retrospectivos , Adulto , Adolescente , SARS-CoV-2 , Adulto Jovem , Criança , Pessoa de Meia-Idade , Doença Aguda , Streptococcus pyogenes , Pré-Escolar , Fusobacterium necrophorum/isolamento & purificação , Distanciamento Físico , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/prevenção & controleRESUMO
Neodymium(III) is a near-infrared emissive and magnetic ion, which has found use in various high-technology applications. Yet, accurate predictions of the luminescent and magnetic properties of neodymium(III) based on the coordination environment remain to be done. Guidelines exist, but to build structure-property relationships for this element, more data are needed. Herein, we present a high-symmetry starting point. The tris(oxidiacetate) complex of neodymium(III) was prepared and crystallized, and access to the experimentally determined structure allowed us to quantify the symmetry of the compound and to perform calculations directly on the same structure that is investigated experimentally. The luminescent properties were determined and the electronic structure was computed using state-of-the-art ab initio methods. All electronic transitions in the range from 490 to 1400 nm were mapped experimentally. Using a Boltzmann population analysis, the combination of the excitation and emission spectra revealed the crystal field splitting of the 18 lowest-energy Kramers levels that experimentally could be unambiguously resolved. This assignment was supported by ab initio calculations, and the crystal field splitting was well reproduced. The electronic structure reported for the tris(oxidiacetate) complex was used to deduce the coordination structure in aqueous solution. Finally, the results are compared to empirical trends in the literature for the electronic structure of neodymium(III).
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Optical information storage requires careful control of excitation and emission wavelengths in a reversible and orthogonal manner to enable efficient reading, writing, and erasing of information. Photochromic systems, in which a photoswitch is typcially coupled to an emissive organic fluorophore, have much promise in this regard. However, these suffer from considerable spectral overlap between the switch and fluorophore, such that their emissive and photoswitchable properties are not orthogonal. Here, we overcome this limitation by coupling visible/NIR emissive lanthanide complexes with molecular photoswitches, enabling reversible and orthogonal photoswitching with visible light. Crucially, photoswitching does not lead to sensitised emission from the lanthanide, while excitation of the lanthanide does not induce photoswitching, enabling the state of the system to be probed without perturbation of the switch. This opens up the possibility of developing multi-colour read-write methods for information storage using emissive photoswitches.
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The structure of molecular systems dictates the physical properties, and symmetry is the determining factor for all electronic properties. This makes group theory a powerful tool in quantum mechanics to compute molecular properties. For inorganic compounds, the coordination geometry has been estimated as idealized polyhedra with high symmetry, which, through ligand field theory, provides predictive capabilities. However, real samples rarely have ideal symmetry, and although continuous shape measures (CShM) can be used to evaluate deviation from an ideal reference structure σideal, this often fails for lanthanide(III) complexes with high coordination numbers, no obvious choice of principal axes, and no obvious reference structure. In lanthanide complexes, the unique electronic structures and associated properties are intricately tied to the symmetry around the lanthanide center. Therefore, robust methodologies to evaluate and estimate point group symmetry are instrumental for building structure-property relationships. Here, we have demonstrated an algorithmic approach that orients a molecular structure Q in the best possible way to the symmetry axis of any given point group G and computes a deviation from the ideal symmetry σsym(G,Q). This approach does not compute the deviation from an ideal reference system, but the intrinsic deviation in the structure induced by symmetry operations. If the structure contains the symmetry operation, there is no deviation and σsym(G,Q) = 0. The σsym deviation is generated from all of the symmetry operation ÔS in a point group G using the most correct orientation of the sample structure in each group G. The best orientation is found by an algorithm that minimizes the orientation of the structure with respect to G. To demonstrate the methodology, we have investigated the structure and symmetry of 8- and 9-coordinated lanthanide(III) aqua complexes and correlated the luminescence from 3 europium(III) crystals to their actual symmetry. To document the methodology, the approach has been tested on 26 molecules with different symmetries. It was concluded that the method is robust and fully autonomous.
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Lanthanide luminescence is characterised by "forbidden" 4f-4f transitions and a complicated electronic structure. Our understanding of trivalent lanthanide(III) ion luminescence is centered on Eu3+ because absorbing and emitting transitions in Eu3+ occur from a single electronic energy level. In Sm3+ both absorbing and emitting multiplets have a larger multiplicity. A band arising in transitions from the first emitting state multiplet to the ground state multiplet will have nine lines for a Sm3+ complex. In this study, high-resolution emission and excitation spectra were used to determine the electronic energy levels for the lowest multiplet and first emitting multiplet in four Sm3+ compounds with either tricapped trigonal prismatic TTP or capped square antiprismatic cSAP coordination polyhedra but different site symmetry. This was achieved by the use of Boltzmann distribution population analysis and experimentally determined transition probabilities from emission and excitation spectra. Using this analysis it was possible to show the effect of changing three oxygen atoms with three nitrogen atoms in the donor set for two compounds with the same coordination polyhedra and site symmetry. This work celebrates the 40th anniversary of Kirby and Richardson's first report of [Eu(ODA)3]3- luminescence.
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Lanthanide luminescence is dominated by quenching by high-energy oscillators in the chemical environment. The rate of non-radiative energy transfer to a single H2O molecule coordinated to a Eu3+ ion exceeds the usual rates of emission by an order of magnitude. We know these rates, but the details of these energy transfer processes are yet to be established. In this work, we study the quenching rates of [Eu(D2O)9]3+ and [Eu(DOTA)(D2O)]- in H2O/D2O mixtures by sequentially exchanging the deuterons with protons. Flash freezing the solutions allows us to identify species with various D/H contents in solution and thus to quantify the energy transfer processes to individual OH-oscillators. This is not possible in solution due to fast exchange in the ensembles present at room temperature. We conclude that the energy transfer processes are accurately described, predicted, and simulated using a step-wise addition of the rates of quenching by each O-H oscillator. This documents the sequential increase in the rate of the energy transfer processes in the quenching of lanthanide luminescence, and further provides a methodology to identify isotopic impurities in deuterated lanthanide systems in solution.
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Introduction: Lateral ankle sprain is the most common ankle injury and up to 40% of those who sustain a lateral ankle sprain will develop chronic ankle instability (CAI). The aim of this study was to explore the thoughts and expectations of CAI-patients concerning their condition and expectations of care in an orthopedic setting.â¯. Study Design: Qualitative study. Methods: Nine semi-structured one-to-one interviews were conducted with CAI-patients who were referred to an orthopedic setting. Interviews were recorded, transcribed, and analyzed using systematic text condensation with an inductive goal free approach.â¯. Results: Seven themes emerged. The themes were Injury history and symptoms (Lateral ankle sprain during sport, pain and instability), Information from health professional (conflicting information about management and prognosis), Management (mental and physical challenges), Expectation and hope (explanation of symptoms, prognosis and imaging to provide clarification of condition), Activity and participation (restriction in sport and daily life and feelings of uncertainty), Support (support from family/friends) and Identity (low ability to participate in sport and social life result in loss of identity).â¯. Conclusion: The impact of CAI exceeds an experience of pain and instability. Patients experienced loss of identity, having to manage uncertainty regarding their diagnosis and prognosis and had hopes of being able to explain their condition.â¯. Level of Evidence: Not applicable.
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The Tb(III) ion has the most intense luminescence of the trivalent lanthanide(III) ions. In contrast to Eu(III), where the two levels only include a single state, the high number of electronic states in the ground (7F6) and emitting (5D4) levels makes detailed interpretations of the electronic structure-the crystal field-difficult. Here, luminescence emission and excitation spectra of Tb(III) complexes with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA, [Tb(DOTA)(H2O)]-), ethylenediaminetetraacetic acid (EDTA, [Tb(EDTA)(H2O)3]-) and diethylenetriaminepentaacetic acid (DTPA, [Tb(DTPA)(H2O)]2-) as well as the Tb(III) aqua ion ([Tb(H2O)9]3+) were recorded at room temperature and in frozen solution. Using these data the electronic structure of the 5D4 multiplets of Tb(III) was mapped by considering the transitions to the singly degenerate 7F0 state. A detailed spectroscopic investigation was performed and it was found that the 5D4 multiplet could accurately be described as a single band for [Tb(H2O)9]3+, [Tb(DOTA)(H2O)]- and [Tb(EDTA)(H2O)3]-. In contrast, for [Tb(DTPA)(H2O)]2- two bands were needed. These results demonstrated the ability of describing the electronic structure of the emitting 5D4 multiplet using emission spectra. This offers an avenue for investigating the relationship between molecular structure and luminescent properties in detailed photophysical studies of Tb(III) ion complexes.
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The formation of the two title compounds, Na3[Sm(DPA)3]·14H2O tris-odium tris-(pyridine-2,6-di-carboxyl-ato-κ3 O 2,N,O 6)samarate(III) tetra-deca-hydrate, Na3[Sm(C7H3NO4)3]·14H2O, and catena-poly[[[di-aqua-(6-carb-oxy-pyridine-2-carb-oxyl-ato-κ3 O 2,N,O 6)samarium(III)]-µ-pyridine-2,6-di-carboxyl-ato-κ4 O 2,N,O 6:O 2] tetra-hydrate], {[Sm(C7H3NO4)(C7H4NO4)(H2O)2]·4H2O}n, depends on the pH value adjusted with NaOH solution. In both crystal structures, the coordination spheres of the SmIII cations were found to be best described by a tricapped trigonal prism (TTP), with a more regular O6N3 donor set for Na3[Sm(DPA)3]·14H2O than that of O7N2 for [Sm(DPA)(HDPA)(H2O)2]·4H2O. The supra-molecular features of both crystal structures are dominated by O-Hâ¯O hydrogen bonds between water mol-ecules and the O atoms of the dipicolinato ligands. Samples were made from solutions at pH = 2, pH = 5, pH = 7, and pH = 10, and the crystals present in each sample were ground to a powder. The powder samples were analyzed with powder X-ray diffraction and luminescence spectroscopy. The splitting of the bands in the luminescence spectra recorded on powders at 77â K was observed to vary with the pH.
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In nature, the elements of the inorganic part of the periodic table are found in three forms: metals, ions in salts & minerals, and ions in solution. The ions may be coordinated to simple or complicated ligands. They may form purely electrostatic or partially covalent bonds. A common trend is that the more covalent bonds an element form, the more we know of its physicochemical properties. The rare earths form purely electrostatic bonds, thus, our understanding of the solution chemistry of these elements is limited-yet important. Most rare earth elements used today pass through hydrometallurgical processes that rely on the solution chemistry of these elements, even through the critical applications are in alloys and functional materials. Through developments in optical spectroscopy, total X-ray scattering, and quantum chemical methods we are posed to remedy this situation: we are ready to create predictive structure-property relationships in the field of lanthanide solution chemistry. The scope of this review is to summarise the state-of-the-art for neodymium(III), to go through the structure-property relationships that are in use. In the form of NdFeB magnets, neodymium plays a crucial role in green energy production and electric propulsion. As a 4f3 ion in solution it is also one of the simpler rare earth ions, and the Nd(III) ion has characteristic optical properties that can be exploited as a handle in physicochemical studies. Here, we start with a critical review of the current concepts used to relate structure and electronic energy levels. We follow with our suggested approach of using the methodology from molecular photophysics to relate optical properties and structure, and conclude with selected literature examples.
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INTRODUCTION: Orthopaedic practice is not always aligned with new evidence which may result in an evidence-practice gap. Our aim was to present and report the use of a new model for implementation of evidence-based practice using treatment of distal radius fractures (DRF) as an example. METHODS: A new implementation model from the Centre for Evidence-Based Orthopaedics (CEBO) was applied. It comprises four phases: 1) baseline practice is held up against best available evidence, and barriers to change are assessed. 2) A symposium involving all stakeholders discussing best evidence is held, and agreement on a new local guideline is obtained. 3) The new guideline based on the decisions at the symposium is prepared and implemented into daily clinical practice. 4) Changes in clinical practice are recorded. We applied the model on the clinical question of whether to use open reduction and internal fixation with a locked volar plate (VLP) or closed reduction and percutaneous pinning (CRPP) in adults with DRF. RESULTS: Prior to application of the CEBO model, only VLP was used in the department. Based on best evidence, the symposium found that a change in practice was justified. A local guideline stating CRPP as first surgical choice was implemented. If acceptable reduction could not be obtained, the procedure was converted to VLP. A year after implementation of the guideline, the rate of VLP had declined from 100% to 44%. CONCLUSION: It is feasible to change surgeons' practice according to best evidence using the CEBO model. FUNDING: None. TRIAL REGISTRATION: Not relevant.
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Cirurgiões Ortopédicos , Cirurgiões , Fraturas do Punho , Adulto , Humanos , Prática Clínica Baseada em Evidências , Lacunas de Evidências , Fixação Interna de FraturasRESUMO
Since Kandinsky's claim for fundamental shape-color associations, several studies have revealed that those tendencies were not generalizable to the entire population and that different associations were more prevalent. Past studies, however, lacked a methodology that allowed participants to freely report their shape-color preferences. Here, we report data from 7,517 Danish individuals, using a free choice full color wheel for five different geometrical shapes. We find significant shape-hue associations for circle-red/yellow, triangle-green/yellow, square-blue, and pentagon/hexagon-magenta. The significant shape-hue associations are also more saturated than non-significant ones for the circle, triangle, and square. At the conceptual level, basic shapes, which show stronger associations, are linked to primary colors, and non-basic shapes to secondary colors. Shape-color associations seem indeed to follow the Berlin-Kay stages of entry into languages. This pattern had previously been described for graphemes and weekday-color associations. The methodology employed in our study can be repeated in different cultural contexts in the future. We also provide another instance of color associations for ordinal concepts that follow the stages of entry into languages.
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Solution chemistry of the lanthanide(III) ions is unexplored and relevant: extraction and recycling processes exclusively operate in solution, MRI is a solution-phase method, and bioassays are done in solution. However, the molecular structure of the lanthanide(III) ions in solution is poorly described, especially for the near-IR (NIR)-emitting lanthanides, as these are difficult to investigate using optical tools, which has limited the availability of experimental data. Here we report a custom-built spectrometer dedicated to investigation of lanthanide(III) luminescence in the NIR region. Absorption, luminescence excitation, and luminescence spectra of five complexes of europium(III) and neodymium(III) were acquired. The obtained spectra display high spectral resolution and high signal-to-noise ratios. Using the high-quality data, a method for determining the electronic structure for the thermal ground states and emitting states is proposed. It combines Boltzmann distributions with population analysis and uses the experimentally determined relative transition probabilities from both excitation and emission data. The method was tested on the five europium(III) complexes and was used to resolve the electronic structures of the ground state and the emitting state of neodymium(III) in five different solution complexes. This is the first step toward correlating optical spectra with chemical structure in solution for NIR-emitting lanthanide complexes.
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BACKGROUND: Few studies have assessed life expectancy of patients with tuberculosis (TB) against a comparable background population, particularly in low-income, high-incidence settings. This study aimed to estimate the life expectancy (LE) of patients with TB in the West African country of Guinea-Bissau and compare it with the LE of the background population. METHODS: This study used data from the Bandim TB cohort from 2004-20 as well as census data from the capital of Guinea-Bissau. LE was estimated using a bootstrapped Kaplan-Meier survival analysis for patients with TB and the background population, stratifying by age of entry and various patient subgroups. The analysis was further stratified by diagnosis period and length of schooling (an indicator of socioeconomic status), to assess their influence on LE. A sensitivity analysis was performed assuming death at loss to follow-up. RESULTS: The analysis included 2278 patients and a background population of 169â760 individuals. Overall median LE among 30-year-old patients with TB was 10.7 years (95% CI: 8.7-12.6), compared with 35.8 (95% CI: 35.1-36.5) in the background population. LE was shorter in HIV-infected patients and those who had unsuccessful treatment outcome; however, even among those who were both uninfected with HIV and experienced successful treatment outcome, LE was 20% shorter than in the background population. Longer schooling appeared to decrease mortality. CONCLUSIONS: TB substantially shortens LE. This effect is present even in patients who are uninfected with HIV and who have successful treatment outcome.
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Infecções por HIV , Tuberculose Pulmonar , Tuberculose , Humanos , Adulto , Guiné-Bissau/epidemiologia , Tuberculose Pulmonar/epidemiologia , Tuberculose/epidemiologia , Expectativa de Vida , Infecções por HIV/epidemiologiaRESUMO
Halide recognition by supramolecular receptors and coordination complexes in water is a long-standing challenge. In this work, we report chloride binding in water and in competing media by pre-organised binuclear kinetically inert lanthanide complexes, bridged by flexible -(CH2)2- and -(CH2)3- spacers, forming [Ln2(DO3A)2C-2] and [Ln2(DO3A)2C-3], respectively. These hydrophilic, neutral lanthanide coordination complexes are shown to bind chloride with apparent association constants of up to 105 M-1 in water and in buffered systems. Hydroxide bridging was observed in these complexes at basic pH, which was proven to be overcome by chloride. Thus, these lanthanide complexes show promise towards chloride recognition in biology and beyond. The results described here have clearly identified a new area of anion coordination chemistry that is ripe for detailed exploration.
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OBJECTIVE: To describe neurophysiological abnormalities in Long COVID and correlate quantitative electromyography (qEMG) and single fiber EMG (sfEMG) results to clinical scores and histopathology. METHODS: 84 patients with non-improving musculoskeletal Long COVID symptoms were examined with qEMG and sfEMG. Muscle biopsies were taken in a subgroup. RESULTS: Mean motor unit potential (MUP) duration was decreased in ≥ 1 muscles in 52 % of the patients. Mean jitter was increased in 17 % of the patients in tibialis anterior and 25 % in extensor digitorum communis. Increased jitter was seen with or without myopathic qEMG. Low quality of life score correlated with higher jitter values but not with qEMG measures. In addition to our previously published mitochondrial changes, inflammation, and capillary injury, we show now in muscle biopsies damage of terminal nerves and motor endplate with abundant basal lamina material. At the endplate, axons were present but no vesicle containing terminals. The post-synaptic cleft in areas appeared atrophic with short clefts and coarse crests. CONCLUSIONS: Myopathic changes are common in Long COVID. sfEMG abnormality is less common but may correlate with clinical scores. sfEMG changes may be due to motor endplate pathology. SIGNIFICANCE: These findings may indicate a muscle pathophysiology behind fatigue in Long COVID.
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COVID-19 , Doenças Musculares , Humanos , Eletromiografia/métodos , Síndrome de COVID-19 Pós-Aguda , Qualidade de Vida , COVID-19/complicações , Músculo Esquelético , FadigaRESUMO
The photophysics of a europium(III) complex of 1,4,7,10-tetraazacycododecane-1,4,7-triacetic acid-10-(2-methylene)-1-azathioxanthone was investigated in three buffer systems and at three pH values. The buffers-phosphate buffered saline (PBS), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), and universal buffer (UB)-had no effect on the europium luminescence, but a lower overall emission intensity was determined in HEPES. It was found that this was due to quenching of the 1-azathioxanthone first excited singlet state by HEPES. The effect of pH on the photophysics of the complex was found to be minimal, and protonation of the pyridine nitrogen was found to be irrelevant. Even so, pH was shown to change the intensity ratio between 1-azathioxanthone fluorescence and europium luminescence. It was concluded that the full photophysics of a potential molecular probe should be investigated to achieve the best possible results in any application.
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The study of optical transitions in lanthanide(III) ions has evolved separately from molecular photophysics, but the framework still applies to these forbidden transitions. In this study, a detailed photophysical characterization of the [Tb(H2O)9]3+ aqua ion was performed. The luminescence quantum yield (Φlum), excited state lifetime (τobs), radiative (kr ≡ A) and nonradiative (knr) rate constants, and oscillator strength (f) were determined for Tb(CF3SO3)3 in H2O/D2O mixtures in order to map the radiative and nonradiative transition probabilities. It was shown that the intense luminescence observed from Tb3+ compared to other Ln3+ ions is not due to a higher transition probability of emission but rather due to a lack of quenching, quantified by quenching to O-H oscillators in the aqua ion of kq(OH) = 2090 s-1 for terbium and kq(OH) = 8840 s-1 for europium. In addition, the Horrocks method of determining inner-sphere solvent molecules has been revisited, and it was concluded that the Tb3+ is 9-coordinated in aqueous solution.
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Lanthanide luminescence fascinates with a complicated electronic structure and "forbidden" transitions. By studying the photophysics of lanthanide(III) solvates, a close to ideal average coordination geometry can be used to map both electronic energy levels and transition probabilities. Some lanthanide(III) ions are simpler to study than others, and samarium(III) belongs to the more difficult ones. The 4f5 system has numerous absorption and emission lines in the visible and infrared parts of the spectrum and in this work, the energy levels giving rise to these transitions were mapped, the transition probability between them was calculated, and it was shown that the electronic structures of the samarium(III) solvates in DMSO, MeOH, and water are different.