Revista Jurídica Digital UANDES
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The importance of clinician, patient and researcher collaborations in Alport syndrome
No full textAlport syndrome is caused by mutations in the genes COL4A3, COL4A4 or COL4A5 and is characterised by progressive glomerular disease, sensorineural hearing loss and ocular defects. Occurring in less than 1:5000, Alport syndrome is a rare genetic disorder but still accounts for > 1% of the prevalent population receiving renal replacement therapy. There is also increasing awareness about the risk of chronic kidney disease in individuals with heterozygous mutations in Alport syndrome genes. The mainstay of current therapy is the use of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, yet potential new therapies are now entering clinical trials. The 2017 International Workshop on Alport Syndrome in Glasgow was a pre-conference workshop ahead of the 50th anniversary meeting of the European Society for Pediatric Nephrology. It focussed on updates in clinical practice, genetics and basic science and also incorporated patient perspectives. More than 80 international experts including clinicians, geneticists, researchers from academia and industry, and patient representatives took part in panel discussions and breakout groups. This report summarises the workshop proceedings and the relevant contemporary literature. It highlights the unique clinician, patient and researcher collaborations achieved by regular engagement between the groups.</p
HNF1B mutations are associated with a Gitelman-like tubulopathy that develops during childhood
No full textBackground: Mutations in the transcription factor HNF1B are the most common inherited cause of renal malformations, yet also associated with renal tubular dysfunction, most prominently magnesium wasting with hypomagnesemia. The presence of hypomagnesemia has been proposed to help select appropriate patients for genetic testing. Yet, in a large cohort, hypomagnesemia was only discriminatory in adult, but not in paediatric patients. We therefore investigated whether hypomagnesemia and other biochemical changes develop with age. Methods: We performed a retrospective analysis of clinical, biochemical and genetic results of paediatric patients with renal malformations tested for HNF1B mutations, separated into 4 age groups. Values were excluded if concurrent estimated glomerular filtration rate (eGFR) was <30 ml/min/1.73m2, or after transplantation. Results: A total of 199 patients underwent HNF1B genetic testing and mutations were identified in 52 (mut+). The eGFRs were comparable between mut+ and mut- in any age group. Although median plasma magnesium concentrations differed significantly between mut+ and mut- patients in all age groups, overt hypomagnesemia was not present until second half of childhood in the mut+ group. There was also a significant difference in median potassium concentrations in late childhood with lower values in the mut+ cohort. Conclusions: The abnormal tubular electrolyte handling associated with HNF1B mutations develops with age and is not restricted to magnesium, but consistent with a more generalized dysfunction of the DCT. The absence of these abnormalities in early childhood should thus not preclude HNF1B mutations from diagnostic considerations
A time-of-flight correction procedure for fast-timing data of recoils with varying implantation positions at a spectrometer focal plane
No full textFast-timing measurements at the focal plane of a separator can suffer from poor timing resolution. This is due to the variations in time-of-flight (ToF) for photons travelling to a given detector, which arise from the changes in the implantation positions of the recoil nuclei emitting the γ rays of interest. In order to minimise these effects on timing measurements, a procedure is presented that improves fast-timing data by performing ToF corrections on an event-by-event basis. This method was used to correct data collected with an array of eight LaBr3 detectors, which detected γ rays from spatially distributed 138Gd recoil-implants at the focal plane of the Recoil-Ion-Transport-Unit (RITU) spectrometer. The Generalised Centroid Difference (GCD) method was used to extract a lifetime from data in conjunction with a new procedure to calibrate the time walk. The lifetime of the first 2+ state in 138Gd, populated by the decay of the Kπ =8- isomeric state, was measured to be 229(24) ps using the ToF-corrected data, which is consistent within three standard deviations to the literature value. The results together with Monte-Carlo simulations show that the ToF correction procedure reduced the uncertainty in the measured lifetimes by 3 % in the case of the spatially distributed nuclei at the focal plane of RITU. However, 12 % has been estimated for a similar experiment when using a larger focal plane i.e. the Super-FRS at the FAIR facility
Self-harm and violent criminality linked with parental death during childhood
No full textBackground: Adverse health and social outcomes are known to occur more frequently following parental death during childhood, but evidence is lacking for comparing long-term risks of internalised versus externalised harm.Methods: This national register-based cohort study consisted of Danish persons born 1970-2000. The Civil Registration System and National Causes of Death Register were linked to ascertain parental deaths by cause before cohort members’ 15th birthdays. From age 15 years, hospital-treated self-harm episodes were ascertained through linkage to the National Patient Register and the Psychiatric Central Research Register, and violent crimes were identified via linkage to the National Crime Register. Hazard ratio and cumulative incidence values were estimated.Results: Self-harm and violent criminality risks were elevated following parental death during childhood. Covariate adjustment for gender, birth year and first-degree relatives’ mental illnesses attenuated these associations, although significantly heightened risks persisted. The estimated hazard ratios did not differ greatly according to which parent died, but losing both parents conferred particularly large risk increases. Risks for both adverse outcomes were higher in relation to unnatural versus natural parental death; violent criminality risk was especially raised among individuals exposed to parental death by unnatural causes other than suicide. The association was strongest when pre-school age children experienced parental death. Conclusions: Effective early intervention is needed to help youngsters who have experienced the death of one or both parents to develop immediate and sustained coping strategies. Enhanced cooperation between health and social services and criminal justice agencies may mitigate risks for these two destructive behaviours.<br/
Kinetics of hydrogenation of acetic acid over supported platinum catalyst
No full textPetroleum is non-renewable and contributes to environmental pollution, thus bio-oil can be substituted as a potential alternative. However, bio-oil in its crude form cannot be used directly as fuel since it contains high proportion of oxygenated, acidic and reactive compounds such as carboxylic acids. These are known to cause corrosion of vessels and pipework, instability and phase separation. The heating value of bio-oil can be improved through hydrodeoxygenation (HDO). In this study, HDO of acetic acid is presented, being a typical model compound found in bio-oil. Kinetic data were obtained over the range of temperature: 175 - 210 ºC, hydrogen pressure: 20-50 bar, initial acetic acid concentration: 0.16-0.521 M and catalyst loading: 0.2-0.5 g, in a 100mL batch reactor using 4% Pt/TiO2. It was found that catalyst particle sizes < 65 μm and a stirring speed of 1000 min-1 were sufficient to overcome internal and external mass transfer resistances and ensure that the reaction is within the kinetic regime. A Langmuir-Hinshelwood model, assuming competitive adsorption of dissociative H2 and acetic acid, fitted the experimental data
Impact of IT ambidexterity on new product development speed: Theory and empirical evidence
No full textNew product development (NPD) speed is becoming an important weapon by which firms can gain market share in today's competitive and complex market environments, where consumer preferences change rapidly. Drawing on the information technology (IT)‐enabled organizational capabilities perspective, this study proposes that IT ambidexterity—the simultaneous pursuit of IT exploitation and IT exploration, which has become imperative in modern industry to sustain the business value of IT—enhances NPD speed by facilitating operational agility. We examine the proposed relationship of IT ambidexterity with the potential moderating role of market complexity in a sample composed of 292 British high‐tech firms. Our findings, based on a moderated‐mediation analysis, suggest that the impact of IT ambidexterity on NPD speed is mediated by operational agility and that the mediation effect is especially pronounced in complex markets. The resulting theoretical arguments and empirical evidence yield further insights into the strategic impacts of IT
Enhancement performance of carbon electrode for supercapacitors by quinone derivatives loading via solvent-free method
No full textActivated carbon (AC) from coconut shell, surface area of 764.09 cm2/g, was functionalized with various quinone derivatives (anthraquinone (AQ), 9,10-phenanthrenequinone (PQ) or tetrachlorohydroquinone (TCHQ)) via a sublimation method for supercapacitor application. The properties of modified activated carbons were characterized by X-ray diffraction (XRD), scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption. The results showed a supercapacitor containing AC modified with 16%wt. AQ achieved higher specific capacitance than other quinone derivatives which performed specific capacitance about 485 F g-1 at a current density of 1.0 A g-1, resistance of 2.25 Ω and exhibited high cyclability which loss specific capacitance of 1.2% after 1000 charge-discharge cycles. The experimental data is in good agreement with the computational results of quinone adsorption on graphene surface; the lowest interaction energy (IE) of -28.0 kcal mol-1 was obtained for AQ loading model. The modified AC successfully prepared by a solvent-free method which could be further developed as low-cost and environmentally friendly electrode materials for high-performance supercapacitors
An Equivalent-Effect Phenomenon in Eddy Current Non-Destructive Testing of Thin Structures
No full textThe inductance/impedance due to thin metallic structures in non-destructive testing (NDT) is difficult to evaluate. In particular, in Finite Element Method (FEM) eddy current simulation, an extremely fine mesh is required to accurately simulate skin effects especially at high frequencies, and this could cause an extremely large total mesh for the whole problem, i.e. including, for example, other surrounding structures and excitation sources like coils. Consequently, intensive computation requirements are needed. In this paper, an equivalent-effect phenomenon is found, which has revealed that alternative structures can produce the same effect on the sensor response, i.e. mutual impedance/inductance of coupled coils if a relationship (reciprocal relationship) between the electrical conductivity and the thickness of the structure is observed. By using this relationship, the mutual inductance/impedance can be calculated from the equivalent structures with much fewer mesh elements, which can significantly save the computation time. In eddy current NDT, coils inductance/impedance is normally used as a critical parameter for various industrial applications, such as flaw detection, coating and microstructure sensing. Theoretical derivation, measurements and simulations have been presented to verify the feasibility of the proposed phenomenon
