Measurement of picosecond lifetimes in neutron-rich Xe isotopes

Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past following isotope separation, thus giving access mainly to the fragments' daughters and only to long-lived isomeric states in the primary fragments. For the first time now, short-lived excited states in the primary fragments, produced in neutron-induced prompt fission of U-235 and Pu-241, were studied within the EXILL&FATIMA campaign at the intense neutron-beam facility of the Institute Laue-Langevin in Grenoble. Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even Xe-138,Xe-140,Xe-142 isotopes lying between the double shell closure N = 82 and Z = 50 and a deformed region with octupole collectivity. Method: The gamma rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGe EXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system has the unique ability to select the interesting fragment making use of the high resolution of the HPGe detectors and determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroid difference method was used. Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above the closed N = 82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations based on shell-model descriptions. Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in the measured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast to higher Z even-even nuclei where abrupt change in deformation occurs around N = 90.

Associação entre a apresentação fenotípica e os indicadores de prognóstico em gatos com cardiomiopatia hipertrófica

Dissertação de Mestrado Integrado em Medicina Veterinária

L1 track finding for a time multiplexed trigger

At the HL-LHC, proton bunches will cross each other every 25. ns, producing an average of 140 pp-collisions per bunch crossing. To operate in such an environment, the CMS experiment will need a L1 hardware trigger able to identify interesting events within a latency of 12.5. μs. The future L1 trigger will make use also of data coming from the silicon tracker to control the trigger rate. The architecture that will be used in future to process tracker data is still under discussion. One interesting proposal makes use of the Time Multiplexed Trigger concept, already implemented in the CMS calorimeter trigger for the Phase I trigger upgrade. The proposed track finding algorithm is based on the Hough Transform method. The algorithm has been tested using simulated pp-collision data. Results show a very good tracking efficiency. The algorithm will be demonstrated in hardware in the coming months using the MP7, which is a μTCA board with a powerful FPGA capable of handling data rates approaching 1. Tb/s.

Detecting Free Riders in Collective Brands through a Hierarchical Choice Process

Free-riding behaviors exist in tourism and they should be analyzed from a comprehensive perspective; while the literature has mainly focused on free riders operating in a destination, the destinations themselves might also free ride when they are under the umbrella of a collective brand. The objective of this article is to detect potential free-riding destinations by estimating the contribution of the different individual destinations to their collective brands, from the point of view of consumer perception. We argue that these individual contributions can be better understood by reflecting the various stages that tourists follow to reach their final decision. A hierarchical choice process is proposed in which the following choices are nested (not independent): “whether to buy,” “what collective brand to buy,” and “what individual brand to buy.” A Mixed Logit model confirms this sequence, which permits estimation of individual contributions and detection of free riders.

False identification of other microorganisms as Staphylococcus aureus in Southern Nigeria

Purpose: Staphylococcus aureus is the causative agent of many infections and the advent MRSA has drawn much attention to it. However, some organisms have been noted to be wrongly identified as S. aureus through phenotypic identifications leading to wrong treatment of infections. This study is therefore undertaken to evaluate the rate of false identification of other organisms as S. aureus in Southern Nigeria. Methods: 507 microorganisms which have been previously identified as S. aureus in 8 States in Southern Nigeria through characteristic morphology on blood agar, Gram staining, growth and fermentation on Mannitol Salt Agar and coagulase formation were collected. All the isolates were identified in this study through sequencing of 16S rRNA and detection of spa gene. The percentages of true and false identities were determined. Results: Of the 507 isolates previously identified as S. aureus, only 54 (11 %) were confirmed as S. aureus while the rest were coagulase negative Staphylococci (85 % misidentification rate), Bacillus sp. (12 % misidentification rate), and Brevibacterium sp. (3 % misidentification rate). Conclusion: A high rate of false positive identification of S. aureus which could lead to the misuse of antibiotics in emergency situation has been identified in this study. The use of standard methods for the identification of S. aureus at all times is highly recommended.

Electrochemical Immunosensing of Cortisol in an Automated Microfluidic System Towards Point-of-Care Applications

This dissertation describes the development of a label-free, electrochemical immunosensing platform integrated into a low-cost microfluidic system for the sensitive, selective and accurate detection of cortisol, a steroid hormone co-related with many physiological disorders. Abnormal levels of cortisol is indicative of conditions such as Cushing’s syndrome, Addison’s disease, adrenal insufficiencies and more recently post-traumatic stress disorder (PTSD). Electrochemical detection of immuno-complex formation is utilized for the sensitive detection of Cortisol using Anti-Cortisol antibodies immobilized on sensing electrodes. Electrochemical detection techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) have been utilized for the characterization and sensing of the label-free detection of Cortisol. The utilization of nanomaterial’s as the immobilizing matrix for Anti-cortisol antibodies that leads to improved sensor response has been explored. A hybrid nano-composite of Polyanaline-Ag/AgO film has been fabricated onto Au substrate using electrophoretic deposition for the preparation of electrochemical immunosening of cortisol. Using a conventional 3-electrode electrochemical cell, a linear sensing range of 1pM to 1µM at a sensitivity of 66µA/M and detection limit of 0.64pg/mL has been demonstrated for detection of cortisol. Alternately, a self-assembled monolayer (SAM) of dithiobis(succinimidylpropionte) (DTSP) has been fabricated for the modification of sensing electrode to immobilize with Anti-Cortisol antibodies. To increase the sensitivity at lower detection limit and to develop a point-of-care sensing platform, the DTSP-SAM has been fabricated on micromachined interdigitated microelectrodes (µIDE). Detection of cortisol is demonstrated at a sensitivity of 20.7µA/M and detection limit of 10pg/mL for a linear sensing range of 10pM to 200nM using the µIDE’s. A simple, low-cost microfluidic system is designed using low-temperature co-fired ceramics (LTCC) technology for the integration of the electrochemical cortisol immunosensor and automation of the immunoassay. For the first time, the non-specific adsorption of analyte on LTCC has been characterized for microfluidic applications. The design, fabrication technique and fluidic characterization of the immunoassay are presented. The DTSP-SAM based electrochemical immunosensor on µIDE is integrated into the LTCC microfluidic system and cortisol detection is achieved in the microfluidic system in a fully automated assay. The fully automated microfluidic immunosensor hold great promise for accurate, sensitive detection of cortisol in point-of-care applications.

High-sensitivity refractive index sensor based on large-angle tilted fiber grating with carbon nanotube deposition

This paper presents a highly sensitive ambient refractive index (RI) sensor based on 81° tilted fiber grating (81°-TFG) structure UV-inscribed in standard telecom fiber (62.5μm cladding radius) with carbon nanotube (CNT) overlay deposition. The sensing mechanism is based on the ability of CNT to induce change in transmitted optical power and the high sensitivity of 81°-TFG to ambient refractive index. The thin CNT film with high refractive index enhances the cladding modes of the TFG, resulting in the significant interaction between the propagating light and the surrounding medium. Consequently, the surrounding RI change will induce not only the resonant wavelength shift but also the power intensity change of the attenuation band in the transmission spectrum. Result shows that the change in transmitted optical power produces a corresponding linear reduction in intensity with increment in RI values. The sample shows high sensitivities of ∼207.38nm/RIU, ∼241.79nm/RIU at RI range 1.344-1.374 and ∼113.09nm/RIU, ∼144.40nm/RIU at RI range 1.374-1.392 (for X-pol and Y-pol respectively). It also shows power intensity sensitivity of ∼ 65.728dBm/RIU and ∼ 45.898 (for X-pol and Y-pol respectively). The low thermal sensitivity property of the 81°-TFG offers reduction in thermal cross-sensitivity and enhances specificity of the sensor.

Use of fluorescence lifetime imaging microscopy (FLIM) as a timer of cell cycle S phase

Incorporation of thymidine analogues in replicating DNA, coupled with antibody and fluorophore staining, allows analysis of cell proliferation, but is currently limited to monolayer cultures, fixed cells and end-point assays. We describe a simple microscopy imaging method for live real-time analysis of cell proliferation, S phase progression over several division cycles, effects of anti-proliferative drugs and other applications. It is based on the prominent (~ 1.7-fold) quenching of fluorescence lifetime of a common cell-permeable nuclear stain, Hoechst 33342 upon the incorporation of 5-bromo-2’-deoxyuridine (BrdU) in genomic DNA and detection by fluorescence lifetime imaging microscopy (FLIM). We show that quantitative and accurate FLIM technique allows high-content, multi-parametric dynamic analyses, far superior to the intensity-based imaging. We demonstrate its uses with monolayer cell cultures, complex 3D tissue models of tumor cell spheroids and intestinal organoids, and in physiological study with metformin treatment.

Fatores significativos na saúde mental das pessoas idosas

A atenção à saúde mental (SM) das pessoas idosas é prioritária. Os problemas de SM neste grupo populacional têm aumentado sendo importante investir na prevenção e rastreio dos mesmos. Este estudo teve como objetivos caraterizar do ponto de vista da SM a população idosa da Região Autónoma da Madeira (RAM); determinar as prevalências das situações de SM positiva e negativa e avaliar a influência positiva (protetora) ou negativa (de risco) de certos fatores pessoais e do meio na SM. Foi um estudo transversal no qual participaram 342 pessoas com 65 e mais anos, dos dois géneros, residentes na comunidade. Destes 67,0 % apresentaram SM positiva. A probabilidade da SM ser mais positiva era 2,5 vezes superior quando possuíam 1 a 11 anos de escolaridade (OR = 2,5 IC 95% 1,3 – 4,8); 0,3 vezes inferior nas mulheres (OR = 0,3 IC 95% 0,1 - 0,6), nos idosos com redes sociais muito limitadas (OR = 0,3 IC 95% 0,1 - 0,9) e nos que percecionavam a saúde como razoável ou pior (OR = 0,3 IC 95% 0,1 - 0,9). Era menor 0,5 vezes quando percecionavam a saúde como pior comparativamente aos pares (OR = 0,5 IC 95% 0,3 - 0,9), e 0,3 vezes comparativamente à detida um ano antes (OR = 0,3 IC 95% 0,2 - 0,6). Era 0,1 vez inferior (OR = 0,1 IC 95% 0,1-0,7) nos idosos com limitações físicas para satisfazerem necessidades próprias. Estes fatores devem considerar-se na promoção da SM e na prevenção de perturbações da mesma.

Clínica médica e cirúrgica em animais de companhia

O presente relatório foi realizado no âmbito do Mestrado Integrado de Medicina Veteri-nária, estando divido em duas partes. A primeira parte refere-se à casuística acompanhada ao longo do estágio curricular, realizado no Centro Hospitalar Veterinário do Porto, no período de-corrido entre 1 de setembro de 2015 e 29 de fevereiro de 2016. A segunda parte engloba uma monografia sobre o tema “Cetoacidose Diabética em canídeos”, incluindo ainda o relato de três casos clínicos acompanhados no decorrer do estágio. A cetoacidose diabética (CAD) é uma complicação urgente do diabetes mellitus, ocorrendo principalmente em animais nunca antes tratados com insulina de longa ação. O diagnóstico de CAD passa pela anamnese, sinais clínicos e deteção de hiperglicemia severa, glicosúria e cetonúria. O diagnóstico e tratamento de doenças concomitantes constituem o passo mais desafiante. O prognóstico depende da severidade da acidose, das doenças concomitantes e das limitações financeiras dos proprietários; Abstract: Small Animal Practice This report was carried out for the completion of the Master degree in veterinary medicine and is divided in two parts. The first part includes the accompanied cases throughout the train-eeship, which was held at the Centro Hospitalar Veterinário of Porto, between September 1st 2015 and February 29th 2016. The second part includes a monograph on "Diabetic Ketoacidosis in dogs ", including the report of three clinical cases followed during the internship. Diabetic ke-toacidosis (DKA) is an urgent complication of diabetes mellitus, occurring mainly in animals that were never treated with long-action insulin. The diagnosis of DKA involves the history, clinical signs and detection of severe hyperglycemia, glycosuria and ketonuria. The diagnosis and treat-ment of concomitant diseases are the most challenging steps. The prognosis depends on the severity of acidosis and concomitant diseases, as well as the financial restrictions of the owners.

Machine learning "as a service" for high energy physics (MLaaS4HEP): evolution of a framework for ML-based physics analyses

The scientific success of the LHC experiments at CERN highly depends on the availability of computing resources which efficiently store, process, and analyse the amount of data collected every year. This is ensured by the Worldwide LHC Computing Grid infrastructure that connect computing centres distributed all over the world with high performance network. LHC has an ambitious experimental program for the coming years, which includes large investments and improvements both for the hardware of the detectors and for the software and computing systems, in order to deal with the huge increase in the event rate expected from the High Luminosity LHC (HL-LHC) phase and consequently with the huge amount of data that will be produced. Since few years the role of Artificial Intelligence has become relevant in the High Energy Physics (HEP) world. Machine Learning (ML) and Deep Learning algorithms have been successfully used in many areas of HEP, like online and offline reconstruction programs, detector simulation, object reconstruction, identification, Monte Carlo generation, and surely they will be crucial in the HL-LHC phase. This thesis aims at contributing to a CMS R&D project, regarding a ML "as a Service" solution for HEP needs (MLaaS4HEP). It consists in a data-service able to perform an entire ML pipeline (in terms of reading data, processing data, training ML models, serving predictions) in a completely model-agnostic fashion, directly using ROOT files of arbitrary size from local or distributed data sources. This framework has been updated adding new features in the data preprocessing phase, allowing more flexibility to the user. Since the MLaaS4HEP framework is experiment agnostic, the ATLAS Higgs Boson ML challenge has been chosen as physics use case, with the aim to test MLaaS4HEP and the contribution done with this work.

A comparison of face and facial feature detectors based on the viola-jones general object detection framework

[EN]The human face provides useful information during interaction; therefore, any system integrating Vision- BasedHuman Computer Interaction requires fast and reliable face and facial feature detection. Different approaches have focused on this ability but only open source implementations have been extensively used by researchers. A good example is the Viola–Jones object detection framework that particularly in the context of facial processing has been frequently used.

Combining face and facial feature detectors for face detection performance improvement

[EN]In this paper, we experimentally study the combination of face and facial feature detectors to improve face detection performance. The face detection problem, as suggeted by recent face detection challenges, is still not solved. Face detectors traditionally fail in large-scale problems and/or when the face is occluded or di erent head rotations are present. The combination of face and facial feature detectors is evaluated with a public database. The obtained results evidence an improvement in the positive detection rate while reducing the false detection rate. Additionally, we prove that the integration of facial feature detectors provides useful information for pose estimation and face alignment.