Silver Complexation by Metallacryptates

We report the first complete characterization of metallycryptates encapsulating Ag(i) cations: carboxylato ligands derived from l-proline and l-alanine chelate and bridge six Cu(ii) centres arranged in a slightly distorted octahedral fashion

Self-Awareness After Brain Injury:Relation with Emotion Recognition and Effects of Treatment

Item does not contain fulltextSelf-awareness is often impaired after acquired brain injury (ABI) and this hampers rehabilitation, in general: unrealistic reports by patients about their functioning and poor motivation and compliance with treatment. We evaluated a self-awareness treatment that was part of a treatment protocol on executive dysfunction (Spikman, Boelen, Lamberts, Brouwer, & Fasotti, 2010). A total of 63 patients were included, aged 17-70, suffering non-progressive ABI, and minimum time post-onset of 3 months. Self-awareness was measured by comparing the patient's Dysexecutive Questionnaire (Wilson, Alderman, Burgess, Emslie, & Evans, 1996) score with that of an independent other. As emotion recognition is associated with self-awareness and influences the effect of rehabilitation treatment, we assessed this function using the Facial Expressions of Emotion-Stimuli and Tests (Young, Perrett, Calder, Sprengelmeyer, & Ekman, 2002). Results showed that patients in the experimental treatment group (n = 29) had better self-awareness after training than control patients (n = 34). Moreover, our results confirmed that the level of self-awareness before treatment was related to emotion recognition. Hence, self-awareness can improve after neuropsychological treatment fostering self-monitoring. Since neuropsychological treatment involves social learning, impairments in social cognition should be taken into account before starting and during treatment.8 p

Relevance of the H_2 + O reaction pathway for the surface formation of interstellar water. Combined experimental and modeling study

The formation of interstellar water is commonly accepted to occur on the surfaces of icy dust grains in dark molecular clouds at low temperatures (10–20 K), involving hydrogenation reactions of oxygen allotropes. As a result of the large abundances of molecular hydrogen and atomic oxygen in these regions, the reaction H_2 + O has been proposed to contribute significantly to the formation of water as well. However, gas-phase experiments and calculations, as well as solid-phase experimental work contradict this hypothesis. Here, we use precisely executed temperature-programmed desorption (TPD) experiments in an ultra-high vacuum setup combined with kinetic Monte Carlo simulations to establish an upper limit of the water production starting from H_2 and O. These reactants were brought together in a matrix of CO_2 in a series of (control) experiments at different temperatures and with different isotopological compositions. The water detected with the quadrupole mass spectrometer upon TPD was found to originate mainly from contamination in the chamber itself. However, if water is produced in small quantities on the surface through H_2 + O, this can only be explained by a combined classical and tunneled reaction mechanism. An absolutely conservative upper limit for the reaction rate was derived with a microscopic kinetic Monte Carlo model that converts the upper limit into the highest possible reaction rate. Incorporating this rate into simulation runs for astrochemically relevant parameters shows that the upper limit to the contribution of the reaction H_2 + O in OH, and hence water formation, is 11% in dense interstellar clouds. Our combined experimental and theoretical results indicate, however, that this contribution is most likely much lower

Anticoagulation in Atrial Fibrillation Patients

Atrial fibrillation (AF) is the most common arrhythmia and may cause thromboembolic events, typically stroke. Advances in pharmacological approaches to anticoagulation and groundbreaking large randomized controlled trials of non-vitamin K antagonist oral anticoagulants (NOACs) have changed the paradigm of anticoagulation therapy. Furthermore, observational studies support the efficacy and safety of NOAC. Few studies address the differences among NOACs, but prescriptions should be based on a thorough understanding of their pharmacological differences, including interactions, side effects, reversibility, and practical approach. In a subset of patients with AF, warfarin may still be the preferable option. Consequently, an individualized approach to oral anticoagulation is crucial

Massive Star Cluster Formation and Destruction in Luminous Infrared Galaxies in GOALS

We present the results of a {\it Hubble Space Telescope} ACS/HRC FUV, ACS/WFC optical study into the cluster populations of a sample of 22 Luminous Infrared Galaxies in the Great Observatories All-Sky LIRG Survey. Through integrated broadband photometry we have derived ages and masses for a total of 484 star clusters contained within these systems. This allows us to examine the properties of star clusters found in the extreme environments of LIRGs relative to lower luminosity star-forming galaxies in the local Universe. We find that by adopting a Bruzual \& Charlot simple stellar population (SSP) model and Salpeter initial mass function, the age distribution of clusters declines as $dN/d\tau = \tau^{-0.9 +/- 0.3}$, consistent with the age distribution derived for the Antennae Galaxies, and interpreted as evidence for rapid cluster disruption occuring in the strong tidal fields of merging galaxies. The large number of $10^{6} M_{\odot}$ young clusters identified in the sample also suggests that LIRGs are capable of producing more high-mass clusters than what is observed to date in any lower luminosity star-forming galaxy in the local Universe. The observed cluster mass distribution of $dN/dM = M^{-1.95 +/- 0.11}$ is consistent with the canonical -2 power law used to describe the underlying initial cluster mass function (ICMF) for a wide range of galactic environments. We interpret this as evidence against mass-dependent cluster disruption, which would flatten the observed CMF relative to the underlying ICMF distribution.Comment: 63 pages, 58 Figures, 56 Tables, Accepted for publication in Ap

Circular frames of the humerus : salvage surgery case series

CITATION: Pretorius, H.S. et al. 2019. Circular frames of the humerus: salvage surgery case series. South African Orthopaedic Journal, 18(4):35-40. doi:10.17159/2309-8309/2019/v18n4a4The original publication is available at https://www.saoj.org.za/index.php/saoj/indexINTRODUCTION: High energy fractures like gunshot-related injuries or high velocity road traffic accidents are often complex to treat and have been associated with a higher non-union rate, especially when there is extensive bone loss. Fractures with severe comminution may not heal due to bone loss and an inability to achieve adequate fracture stability. Treatment of fractures that are not amenable to plating or nailing may lead to non-unions, septic or aseptic, that need repeat surgeries. Stabilisation with external fixation is a reliable option to maintain stability and provide a suitable environment for union. MATERIALS AND METHODS: This retrospective study used medical records of all patients with complex mid-shaft humerus fractures, as well as their complications, that were treated with hexapod circular external fixation between January 2009 and September 2015. All the patients in this case series presented with severe humerus fractures or complications thereof which were not amenable to conventional therapy. RESULTS: Union was achieved in ten out of the 12 cases (83.3%). Union was achieved without bone graft or any other interventions at the fracture site except implant removal where indicated. The median time in external fixation was 196 days (interquartile range: 112-228). The most common complication encountered in this series was pin-site infection. Fixation points were noted to be infected in 33% of cases at some time during the treatment period. CONCLUSION: This study suggests that humeral non-unions and complex humerus fractures that are not amenable to conventional fixation methods, such as intramedullary nails and plates, can successfully achieve union when treated with a hexapod circular external fixator. Level of evidence: Level 4https://www.saoj.org.za/index.php/saoj/article/view/309Publisher’s versio

A lethal blistering autoimmune disease

Dermatomyositis is an autoimmune disease characterized by chronic inflammation of skin and muscle. Anti-melanoma differentiation-associated gene 5 (MDA5) associated dermatomyositis is a recently described variant that displays a unique dermatological phenotype consisting of punched-out cutaneous ulcers, palmar erythema, papules or blisters at typical sites of dermatomyositis. Moreover, anti-MDA5 associated dermatomyositis patients have an increased risk to develop a rapidly progressive interstitial lung disease with a potentially fatal course. Cutaneous ulcers are an important predictor for the development of interstitial lung disease. We report an illustrative case of anti-MDA5 associated dermatomyositis.</p

A lethal blistering autoimmune disease

Dermatomyositis is an autoimmune disease characterized by chronic inflammation of skin and muscle. Anti-melanoma differentiation-associated gene 5 (MDA5) associated dermatomyositis is a recently described variant that displays a unique dermatological phenotype consisting of punched-out cutaneous ulcers, palmar erythema, papules or blisters at typical sites of dermatomyositis. Moreover, anti-MDA5 associated dermatomyositis patients have an increased risk to develop a rapidly progressive interstitial lung disease with a potentially fatal course. Cutaneous ulcers are an important predictor for the development of interstitial lung disease. We report an illustrative case of anti-MDA5 associated dermatomyositis.</p

A taxonomy to assess the interaction between nurses and children:Development and reliability

Aims and objectives The aim of this study was to develop a valid and reliable instrument to assess the nurse-child interaction during medical or nursing interventions. Background Communication is an important competency for the professional practice of nurses and physicians. The nurse-patient relationship is fundamental for high-quality care. It has been suggested that if nurses have more skills to interact with children, care will be less distressing and less painful for the children. Design A qualitative observational psychometric study; the GRRAS checklist was used. Methods In-depth video-analyses, taxonomy development (19 videos) and testing it is psychometric properties (10 videos). Three observers micro-analysed video recordings of experienced nurses changing children's wound dressing in a specialised Burn Centre. Results The nurse-child interaction taxonomy (NCIT) was developed to observe and score the interactional behaviour between nurse and child. The taxonomy has three main patterns: being considerate, attuning oneself, and procedural interventions, subdivided in eight dimensions. These dimensions contain 16 elements that can be observed and scored on a 7-point scale. Intra-rater, inter-rater reliability and agreement were good. Conclusions This study shows that interaction between nurses and children can be assessed reliably with the NCIT by an experienced observer or alternatively, scoring by two observers is recommended. Relevance to clinical practice The development of the taxonomy is an important step to find evidence for the best way for nurses to interact with children during nursing interventions or medical events and as such, ultimately, contributes to providing the best care possible