Conceptual design of the early implementation of the NEutron Detector Array (NEDA) with AGATA

The NEutron Detector Array (NEDA) project aims at the construction of a new high-efficiency compact neutron detector array to be coupled with large (Formula presented.) -ray arrays such as AGATA. The application of NEDA ranges from its use as selective neutron multiplicity filter for fusion-evaporation reaction to a large solid angle neutron tagging device. In the present work, possible configurations for the NEDA coupled with the Neutron Wall for the early implementation with AGATA has been simulated, using Monte Carlo techniques, in order to evaluate their performance figures. The goal of this early NEDA implementation is to improve, with respect to previous instruments, efficiency and capability to select multiplicity for fusion-evaporation reaction channels in which 1, 2 or 3 neutrons are emitted. Each NEDA detector unit has the shape of a regular hexagonal prism with a volume of about 3.23l and it is filled with the EJ301 liquid scintillator, that presents good neutron- (Formula presented.) discrimination properties. The simulations have been performed using a fusion-evaporation event generator that has been validated with a set of experimental data obtained in the 58Ni + 56Fe reaction measured with the Neutron Wall detector array

Non-invasive ventilation in obesity hypoventilation syndrome without severe obstructive sleep apnoea

Background Non-invasive ventilation (NIV) is an effective form of treatment in patients with obesity hypoventilation syndrome (OHS) who have concomitant severe obstructive sleep apnoea (OSA). However, there is a paucity of evidence on the efficacy of NIV in patients with OHS without severe OSA. We performed a multicentre randomised clinical trial to determine the comparative efficacy of NIV versus lifestyle modification (control group) using daytime arterial carbon dioxide tension (PaCO2) as the main outcome measure. Methods Between May 2009 and December 2014 we sequentially screened patients with OHS without severe OSA. Participants were randomised to NIV versus lifestyle modification and were followed for 2 months. Arterial blood gas parameters, clinical symptoms, health-related quality of life assessments, polysomnography, spirometry, 6-min walk distance test, blood pressure measurements and healthcare resource utilisation were evaluated. Statistical analysis was performed using intention-to-treat analysis. Results A total of 365 patients were screened of whom 58 were excluded. Severe OSA was present in 221 and the remaining 86 patients without severe OSA were randomised. NIV led to a significantly larger improvement in PaCO2 of -6 (95% CI -7.7 to -4.2) mm Hg versus -2.8 (95% CI -4.3 to -1.3) mm Hg, (p<0.001) and serum bicarbonate of -3.4 (95% CI -4.5 to -2.3) versus -1 (95% CI -1.7 to -0.2 95% CI) mmol/L (p<0.001). PaCO2 change adjusted for NIV compliance did not further improve the inter-group statistical significance. Sleepiness, some health-related quality of life assessments and polysomnographic parameters improved significantly more with NIV than with lifestyle modification. Additionally, there was a tendency towards lower healthcare resource utilisation in the NIV group. Conclusions NIV is more effective than lifestyle modification in improving daytime PaCO2, sleepiness and polysomnographic parameters. Long-term prospective studies are necessary to determine whether NIV reduces healthcare resource utilisation, cardiovascular events and mortality

Pulse pile-up identification and reconstruction for liquid scintillator based neutron detectors

The issue of pulse pile-up is frequently encountered in nuclear experiments involving high counting rates, which will distort the pulse shapes and the energy spectra. A digital method of off-line processing of pile-up pulses is presented. The pile-up pulses were firstly identified by detecting the downward-going zero-crossings in the first-order derivative of the original signal, and then the constituent pulses were reconstructed based on comparing the pile-up pulse with four models that are generated by combining pairs of neutron and γ standard pulses together with a controllable time interval. The accuracy of this method in resolving the pile-up events was investigated as a function of the time interval between two pulses constituting a pile-up event. The obtained results show that the method is capable of disentangling two pulses with a time interval among them down to 20 ns, as well as classifying them as neutrons or γ rays. Furthermore, the error of reconstructing pile-up pulses could be kept below 6% when successive peaks were separated by more than 50 ns. By applying the method in a high counting rate of pile-up events measurement of the NEutron Detector Array (NEDA), it was empirically found that this method can reconstruct the pile-up pulses and perform neutron-γ discrimination quite accurately. It can also significantly correct the distorted pulse height spectrum due to pile-up events

[Translated article] Management of vertebral metastases in the cervico-occipital junction

Occipito-cervical metastases correspond to 0.5% of spinal metastases. The management of these lesions is complex and involves multiple radiological studies, such as simple radiology, computed tomography (CT), magnetic resonance imaging (MRI). Is vascular involvement is suspected, tests to assess vascular permeability are also recommended (angioCT). This type of lesion, due to its complex location, may require different types of approaches, commonly it will be the posterior approach, but sometimes anterior or antero-lateral approaches will be needed assisted by maxillofacial surgeons or otorhinolaryngologists for correct excision of the tumour. Pain with head turning can guide us to the diagnosis in an unstable spine. Magnetic resonance is the test of choice to diagnose and study these lesions. The presence of instability or progressive neurological symptoms is an indication for surgery. Resumen: Las metástasis a nivel occipitocervical corresponden solo al 0,5% de las metástasis del raquis. El manejo de estas lesiones es complejo y conlleva múltiples estudios radiológicos, tales como la radiología simple, la tomografía computarizada (TC) o la resonancia magnética (RM). Ante la sospecha de afectación vascular también será recomendable la realización de pruebas que valoren la permeabilidad vascular (angio-TC, angio-RM). Este tipo de lesiones, debido a su compleja localización, puede precisar distintos tipos de vías de abordaje; comúnmente será el abordaje posterior, pero en ocasiones se necesitarán abordajes anteriores o anterolaterales asistidos por cirujanos maxilofaciales u otorrinolaringólogos para una correcta exéresis de la tumoración. El dolor con los giros puede orientarnos al diagnóstico en una columna inestable. La RM es la prueba de elección para diagnosticar y estudiar estas lesiones. La presencia de inestabilidad o de clínica neurológica progresiva es indicación de cirugía

Manejo de las metástasis vertebrales en la charnela cervico-occipital

Resumen: Las metástasis a nivel occipito-cervical corresponden solo al 0,5% de las metástasis del raquis. El manejo de estas lesiones es complejo y conlleva múltiples estudios radiológicos, tales como la radiología simple, la tomografía computarizada (TAC) o la resonancia magnética (RM). Ante la sospecha de afectación vascular también será recomendable la realización de pruebas que valoren la permeabilidad vascular (angio-TC, angio-RM). Este tipo de lesiones, debido a su compleja localización, puede precisar distintos tipos de vías de abordaje; comúnmente será el abordaje posterior, pero en ocasiones se necesitarán abordajes anteriores o anterolaterales asistidos por cirujanos maxilofaciales u otorrinolaringólogos para una correcta exéresis de la tumoración. El dolor con los giros puede orientarnos al diagnóstico en una columna inestable. La RM es la prueba de elección para diagnosticar y estudiar estas lesiones. La presencia de inestabilidad o de clínica neurológica progresiva es indicación de cirugía. Abstract: Occipito-cervical metastases correspond to 0.5% of spinal metastases. The management of these lesions is complex and involves multiple radiological studies, such as simple radiology, computed tomography (CT), magnetic resonance imaging (MRI). Is vascular involvement is suspected, tests to assess vascular permeability are also recommended (angioCT). This type of lesion, due to its complex location, may require different types of approaches, commonly it will be the posterior approach, but sometimes anterior or anterolateral approaches will be needed assisted by maxillofacial surgeons or otorhinolaryngologists for correct excision of the tumor. Pain with head turning can guide us to the diagnosis in an unstable spine. Magnetic resonance is the test of choice to diagnose and study these lesions. The presence of instability or progressive neurological symptoms are an indication for surgery

NMR studies of the soluble metal binding domains of the copper transport ATPase from B-subtilis

Regulation of intracellular copper activity is crucially important for cell life. Copper is very toxic to both eukaryotic and prokaryotic cells as it is involved in oxidative reactions with the production of radicals. In bacteria the mechanisms of copper homeostasis are poorly understood. CopA, a P-type membrane bound ATPase of B. subtilis, is apparently involved in copper binding and transport; it contains two cysteines in each of two putative soluble N-terminal metal binding domains. In this work the structural characterization of the two soluble domains has been performed by NMR. Complete resonances only for the second domain can be detected while the first one shows only signals for a few residues. The same behavior is observed also for the individual, isolated domains, indicating a not complete folding for the first domain. Atomic absorption determination revealed a 1:1 copper/protein ratio. The goal of this work is to investigate the influence of copper binding in the protein structure, in order to better understand the mechanism of copper homeostasis in bacteria