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1.
IEEE Trans Vis Comput Graph ; 26(5): 1912-1922, 2020 05.
Article En | MEDLINE | ID: mdl-32070968

Directivity and gain in microphone array systems for hearing aids or hearable devices allow users to acoustically enhance the information of a source of interest. This source is usually positioned directly in front. This feature is called acoustic beamforming. The current study aimed to improve users' interactions with beamforming via a virtual prototyping approach in immersive virtual environments (VEs). Eighteen participants took part in experimental sessions composed of a calibration procedure and a selective auditory attention voice-pairing task. Eight concurrent speakers were placed in an anechoic environment in two virtual reality (VR) scenarios. The scenarios were a purely virtual scenario and a realistic 360° audio-visual recording. Participants were asked to find an individual optimal parameterization for three different virtual beamformers: (i) head-guided, (ii) eye gaze-guided, and (iii) a novel interaction technique called dual beamformer, where head-guided is combined with an additional hand-guided beamformer. None of the participants were able to complete the task without a virtual beamformer (i.e., in normal hearing condition) due to the high complexity introduced by the experimental design. However, participants were able to correctly pair all speakers using all three proposed interaction metaphors. Providing superhuman hearing abilities in the form of a dual acoustic beamformer guided by head and hand movements resulted in statistically significant improvements in terms of pairing time, suggesting the task-relevance of interacting with multiple points of interests.


Acoustics/instrumentation , Hearing Aids , Hearing/physiology , Signal Processing, Computer-Assisted/instrumentation , Virtual Reality , Acoustic Stimulation , Adult , Auditory Perception/physiology , Equipment Design , Female , Humans , Male , Young Adult
2.
Vet Parasitol Reg Stud Reports ; 12: 99-105, 2018 05.
Article En | MEDLINE | ID: mdl-31014818

Originally described in cattle, conglutinin belongs to the collectin family and is involved in innate immune defense. It is thought that conglutinin provides the first line of defense by maintaining a symbiotic relationship with the microbes in the rumen while inhibiting inflammatory reactions caused by antibodies leaking into the bloodstream. Due to the lack of information on the similar lectins and sequence detection in goats, we characterized the goat conglutinin gene using RACE and evaluated the differences in its gene expression profile, as well as in the gene expression profiles for surfactant protein A, galectins 14 and 11, interleukin 4 and interferon-gamma in goats. We used Saanen and Anglo Nubian F2 crossbred goats monitored over a period of four months and characterized them as resistant (R) or susceptible (S) based on the average values of EPG counts. Goat conglutinin was similar to bovine conglutinin, but its gene expression varied among different tissues. However, as with bovine conglutinin, it was most highly expressed in the liver. Variation in conglutinin (R=24.3±3.9; S=23.5±2.6, p=0.059), protein surfactant A (R=23.8±5.2, S=24.4±2.3, p=0.16), galectin 14 (R=15.9±3.5, S=14.7±6.2, p=0.49) and galectin l1 gene expression (R=25.4±2.6, S=25.8±3.7, p=0.53) was not significant between groups. However, there were weak correlations between interleukin 4 and the protein surfactant A gene (r=0.459, p=0.02) and between interleukin 4 and galectin 11 (r=0.498, p=0.01). Strong correlation between interferon-gamma and galectin 14 (r=0.744, p=0.00) was observed. Galectin 14 was negatively correlated with the number of nematodes in the goat (r=-0.416, p=0.04) as well as the EPG count (r=-0.408, p=0.04). This is the first study to date that identifies the gene expression of conglutinin, surfactant protein A and galectins 14 and 11 in the goat abomasum. In conclusion, we present evidence that lectin is involved in the immune response to gastrointestinal nematodes, which suggests that collectins and galectins are involved in the molecular recognition of helminths.


Abomasum/immunology , Collectins/genetics , Galectins/genetics , Goat Diseases/immunology , Goat Diseases/parasitology , Nematode Infections/immunology , Animals , Collectins/immunology , Disease Resistance/immunology , Female , Galectins/immunology , Gastrointestinal Diseases/immunology , Gastrointestinal Diseases/parasitology , Gastrointestinal Tract/parasitology , Gene Expression Profiling , Goats/parasitology , Immunity, Innate , Interleukin-4/genetics , Male , Pulmonary Surfactant-Associated Protein A/genetics , Real-Time Polymerase Chain Reaction , Serum Globulins/genetics , Serum Globulins/immunology
3.
Lupus Sci Med ; 4(1): e000184, 2017.
Article En | MEDLINE | ID: mdl-28123769

OBJECTIVES: To assess the prevalence and severity of ultrasonographic abnormalities of the hand and wrist of asymptomatic patients with systemic lupus erythematosus (SLE) and compare these findings with those from patients with SLE with musculoskeletal signs or symptoms and healthy controls. METHODS: We conducted a prospective cross-sectional study that evaluated bilaterally, with grey-scale and power Doppler (PD) ultrasound (US), the dorsal hand (2nd to 5th metacarpophalangeal and 2nd to 5th proximal interphalangeal joints) and wrist (radiocarpal, ulnocarpal and intercarpal joints) of 30 asymptomatic patients with SLE, 6 symptomatic patients with SLE and 10 controls. Synovial hypertrophy (SH) and intra-articular PD signal were scored using semiquantitative grading scales (0-3). Individual scores were graded as normal (SH≤1 and PD=0) or abnormal (SH≥2 or PD≥1). Global indexes for SH and PD were also calculated. US findings were correlated with clinical and laboratory data and disease activity indexes. RESULTS: US detected SH (score ≥1) in 77% asymptomatic patients with SLE, mostly graded as minimal (score 1: 63%). 23% of the asymptomatic patients with SLE showed abnormal US PD findings (SH≥2 or PD≥1). SH was present in all symptomatic patients with SLE, mostly graded as moderate (grade 2: 67%), and with associated PD signal (83%). SH (score 1) was identified in 50% of controls, however, none presented abnormal US PD findings. SH index in the asymptomatic SLE group was higher than in the control group (2.0 (0-5) vs 0.5 (0-2), median (range), p=0.01) and lower than in the symptomatic SLE group (7.0 (4-23), median (range), p<0.001). No significant correlation was demonstrated between US PD findings and clinical or laboratory variables and disease activity indexes. CONCLUSION: A small subgroup of asymptomatic patients with SLE may present subclinical joint inflammation. Global US scores and PD signal may be important in disease evaluation and therapeutic monitoring.

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