159 research outputs found
Sensitivity of Machine Learning Approaches to Fake and Untrusted Data in Healthcare Domain
Machine Learning models are susceptible to attacks, such as noise, privacy invasion, replay, false data injection, and evasion attacks, which affect their reliability and trustworthiness. Evasion attacks performed to probe and identify potential ML-trained models’ vulnerabilities, and poisoning attacks, performed to obtain skewed models whose behavior could be driven when specific inputs are submitted, represent a severe and open issue to face in order to assure security and reliability to critical domains and systems that rely on ML-based or other AI solutions, such as healthcare and justice, for example. In this study, we aimed to perform a comprehensive analysis of the sensitivity of Artificial Intelligence approaches to corrupted data in order to evaluate their reliability and resilience. These systems need to be able to understand what is wrong, figure out how to overcome the resulting problems, and then leverage what they have learned to overcome those challenges and improve their robustness. The main research goal pursued was the evaluation of the sensitivity and responsiveness of Artificial Intelligence algorithms to poisoned signals by comparing several models solicited with both trusted and corrupted data. A case study from the healthcare domain was provided to support the pursued analyses. The results achieved with the experimental campaign were evaluated in terms of accuracy, specificity, sensitivity, F1-score, and ROC area
La presbiacusia. problematiche, diagnosi e opzioni riabilitative Presbycusis. problems, diagnosis and treatment
Presbycusis is sensorineural bilateral symmetrical, progressive hearing loss, caused by the advance
of age. It involves mainly the higher frequencies and associated with tinnitus. Presbycusis the most
frequent form of sensorineural hearing loss of the adult, characterized by the progressive difficulty following
the conversation, especially in noisy environments. It is caused by reduction in the number of
Corti cells, induced by genetic and environmental factors. In the elderly communication disorders generate
isolation and depression, thereby causing a significant reduction of life quality. An observational
study at our hospital in 2010, using questionnaires on verbal-acoustic communication (Self Assessment
of Communication), found that older people have a poor perception of disability related to hearing
loss. For presbycusis to be diagnosed, tone audiometry and speech and sovraliminary tests have to be
carried out and must be integrated with the evaluation of extremely high frequencies (EHFs). In the
majority of cases, rehabilitation involves conventional hearing aids. The most commonly used are retroauricular
hearing aids, when these are contraindicated partially or totally implantable hearing device
scan be used. Careful follow up of the patient is also fundamental, using benefit questionnaires to find
the optimal fitting and therefore the best result
Lysine: N 6 -Hydroxylase: Stability and Interaction with Ligands
Recombinant lysine:N 6 -hydroxylase, r IucD, which is isolated as an apoenzyme, requires FAD and NADPH for its catalytic function. r IucD preparations have been found to undergo time-dependent loss in monooxygenase function due to aggregation from the initial tetrameric state to a polytetrameric form(s), a process which is reversible by treatment with thiols. Ligand-in-duced conformational changes in r IucD were assessed by monitoring its CD spectra, DSC profile, and susceptibility to both endo- as well as exopeptidases. The first two methods indicated the absence of any significant conformational change in r IucD, while the last approach revealed that FAD, and its analog ADP, can protect the protein from the deleterious action of proteases. NADPH was partially effective and L-lysine was ineffective in this regard. Deletion of the C-terminal segment, either by treatment with carboxypeptidase Y or by mutagenesis of iucD, results in the loss of r IucD's monooxygenase activity. These findings demonstrate the crucial role of the C-terminal segment in maintaining r IucD in its native conformation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45085/1/10930_2004_Article_409465.pd
Atmospheric phase correction using CARMA-PACS: high angular resolution observations of the FU Orionis star PP 13S*
We present 0".15 resolution observations of the 227 GHz continuum emission from the circumstellar disk around
the FU Orionis star PP 13S*. The data were obtained with the Combined Array for Research in Millimeter-wave
Astronomy (CARMA) Paired Antenna Calibration System (C-PACS), which measures and corrects the atmospheric
delay fluctuations on the longest baselines of the array in order to improve the sensitivity and angular resolution of
the observations. A description of the C-PACS technique and the data reduction procedures are presented. C-PACS
was applied to CARMA observations of PP 13S*, which led to a factor of 1.6 increase in the observed peak flux
of the source, a 36% reduction in the noise of the image, and a 52% decrease in the measured size of the source
major axis. The calibrated complex visibilities were fitted with a theoretical disk model to constrain the disk surface
density. The total disk mass from the best-fit model corresponds to 0.06 M_⊙, which is larger than the median mass of a disk around a classical T Tauri star. The disk is optically thick at a wavelength of 1.3 mm for orbital radii less than 48 AU. At larger radii, the inferred surface density of the PP 13S* disk is an order of magnitude lower than that needed to develop a gravitational instability
Atmospheric phase correction using the CARMA paired antennas calibration system
High angular resolution observations are essential to understand a variety of astrophysical phenomena. The resolution of millimeter wave interferometers is limited by large and rapid differential atmospheric delay fluctuations. At the Combined Array for Research in Millimeter-wave Astronomy (CARMA) we have employed a Paired Antenna Calibration System (C-PACS) for atmospheric phase compensation in the extended array configurations (up to 2 km baselines). We present a description of C-PACS and its application. We also present successful atmospheric delay corrections applied to science observations with dramatic improvements in sensitivity and angular resolution
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First M87 Event Horizon Telescope Results. III. Data Processing and Calibration
We present the calibration and reduction of Event Horizon Telescope (EHT) 1.3 mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the quasar 3C 279, taken during the 2017 April 5-11 observing campaign. These global very long baseline interferometric observations include for the first time the highly sensitive Atacama Large Millimeter/submillimeter Array (ALMA); reaching an angular resolution of 25 mu as, with characteristic sensitivity limits of similar to 1 mJy on baselines to ALMA and similar to 10 mJy on other baselines. The observations present challenges for existing data processing tools, arising from the rapid atmospheric phase fluctuations, wide recording bandwidth, and highly heterogeneous array. In response, we developed three independent pipelines for phase calibration and fringe detection, each tailored to the specific needs of the EHT. The final data products include calibrated total intensity amplitude and phase information. They are validated through a series of quality assurance tests that show consistency across pipelines and set limits on baseline systematic errors of 2% in amplitude and 1 degrees in phase. The M87 data reveal the presence of two nulls in correlated flux density at similar to 3.4 and similar to 8.3 G lambda and temporal evolution in closure quantities, indicating intrinsic variability of compact structure on a. timescale of days, or several light-crossing times for a. few billion solar-mass black hole. These measurements provide the first opportunity to image horizon-scale structure in M87.Academy of Finland [274477, 284495, 312496]; European Commission Framework Programme Horizon 2020 Research and Innovation action [731016]; Black Hole Initiative at Harvard University through John Templeton Foundation [60477]; Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, Chile) [PIA ACT172033, Fondecyt 1171506, BASAL AFB-170002, ALMA-conicyt 31140007]; Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico) [104497, 275201, 279006, 281692]; Direccion General de Asuntos del Personal Academico-Universidad Nacional Autonoma de Mexico (DGAPA-UNAM) [IN112417]; European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" [610058]; Generalitat Valenciana postdoctoral grant [APOSTD/2018/177]; Gordon and Betty Moore Foundation [GBMF 947, GBMF-3561, GBMF-5278]; Japanese Government (Monbukagakusho: MEXT) Scholarship; Japan Society for the Promotion of Science (JSPS) [JP17J08829]; JSPS Overseas Research Fellowships; Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS) [QYZDJ-SSW-SLH057, QYZDJ-SSW-SYS008]; Leverhulme Trust Early Career Research Fellowship; MEXT/JSPS KAKENHI [18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007]; MIT International Science and Technology Initiatives (MISTI) Funds; Ministry of Science and Technology (MOST) of Taiwan [105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119-M-001-027, 107-2119-M-001-017, 107-2119-M-001-020, 107-2119-M-110-005]; National Aeronautics and Space Administration (NASA) [80NSSC17K0649]; National Key Research and Development Program of China [2016YFA0400704, 2016YFA0 400702]; National Science Foundation (NSF) [AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730]; Natural Science Foundation of China [11573051, 11633006, 11650110427, 10625314, 11721303, 11725312, 11873028, 11873073, U1531245, 11473010]; Natural Sciences and Engineering Research Council of Canada (NSERC); National Research Foundation of Korea [2015-R1D1A1A01056807, NRF-2015H1A2A1033752, NRF-2015H1D3A1066561]; Netherlands Organization for Scientific Research (NWO) VICI award [639.043.513]; Spinoza Prize [SPI 78-409]; Swedish Research Council [2017-00648]; Government of Canada through the Department of Innovation, Science and Economic Development Canada; Province of Ontario through the Ministry of Economic Development, Job Creation and Trade; Russian Science Foundation [17-12-01029]; Spanish Ministerio de Economia y Competitividad [AYA2015-63939-C2-1-P, AYA2016-80889-P]; US Department of Energy (USDOE) through the Los Alamos National Laboratory [89233218CNA000001]; Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA [CUP C52I13000140001]; ALMA North America Development Fund; NSF [ACI-1548562, DBI-0735191, DBI-1265383, DBI-1743442]; Smithsonian Institution; Academia Sinica; National Key R&D Program of China [2017YFA0402700]; Science and Technologies Facility Council (UK); CNRS (Centre National de la Recherche Scientifique, France); MPG(Max-Planck-Gesellschaft, Germany); IGN (Instituto Geografico Nacional, Spain); State of Arizona; NSF Physics Frontier Center award [PHY-0114422]; Kavli Foundation; National Science Foundation [PLR-1248097]; NSF Physics Frontier Center [PHY-1125897]; Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award [SEV-2017-0709]; European Union' s Horizon 2020 research and innovation programme [730562 RadioNet]; GBMF [GBMF-947]; Compute Ontario; Calcul Quebec; Compute Canada; NSF; CyVerse; [Chandra TM6-17006X]; [AST-1207752]; [MRI-1228509]; [OPP-1248097]; [AST-1310896]; [AST-1312651]; [AST-1337663]; [AST-1440254]; [AST-1555365]; [AST-1715061]; [AST-1615796]; [AST-1716327]; [OISE-1743747]; [AST-1816420]; [AST-1614868]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. 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Molecular basis of mucopolysaccharidosis IVA (Morquio A syndrome) : a review and classification of GALNS gene variants and reporting of 68 novel variants
Mucopolysaccharidosis IVA (MPS IVA, Morquio A syndrome) is a rare autosomal recessive lysosomal storage disorder caused by mutations in the N-acetylgalactosamine-6-sulfatase (GALNS) gene. We collected, analyzed, and uniformly summarized all published GALNS gene variants, thus updating the previous mutation review (published in 2014). In addition, new variants were communicated by seven reference laboratories in Europe, the Middle East, Latin America, Asia, and the United States. All data were analyzed to determine common alleles, geographic distribution, level of homozygosity, and genotype-phenotype correlation. Moreover, variants were classified according to their pathogenicity as suggested by ACMG. Including those previously published, we assembled 446 unique variants, among which 68 were novel, from 1190 subjects (including newborn screening positive subjects). Variants' distribution was missense (65.0%), followed by nonsense (8.1%), splicing (7.2%), small frameshift deletions(del)/insertions(ins) (7.0%), intronic (4.0%), and large del/ins and complex rearrangements (3.8%). Half (50.4%) of the subjects were homozygous, 37.1% were compound heterozygous, and 10.7% had only one variant detected. The novel variants underwent in silico analysis to evaluate their pathogenicity. All variants were submitted to ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/) to make them publicly available. Mutation updates are essential for the correct molecular diagnoses, genetic counseling, prenatal and preimplantation diagnosis, and disease management
A VLBI receiving system for the South Pole Telescope
The Event Horizon Telescope (EHT) is a very-long-baseline interferometry
(VLBI) experiment that aims to observe supermassive black holes with an angular
resolution that is comparable to the event horizon scale. The South Pole
occupies an important position in the array, greatly increasing its north-south
extent and therefore its resolution.
The South Pole Telescope (SPT) is a 10-meter diameter, millimeter-wavelength
telescope equipped for bolometric observations of the cosmic microwave
background. To enable VLBI observations with the SPT we have constructed a
coherent signal chain suitable for the South Pole environment. The
dual-frequency receiver incorporates state-of-the-art SIS mixers and is
installed in the SPT receiver cabin. The VLBI signal chain also includes a
recording system and reference frequency generator tied to a hydrogen maser.
Here we describe the SPT VLBI system design in detail and present both the lab
measurements and on-sky results.Comment: 14 pages, 11 figures, to appear in the Proceedings of the SPIE (SPIE
Astronomical Telescopes + Instrumentation 2018; Millimeter, Submillimeter,
and Far-Infrared Detectors and Instrumentation for Astronomy IX
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