190 research outputs found
Joint Communication and Sensing Design for Beyond 5G System
Joint communication and sensing (JCAS) is an emerging research topic aiming to integrate radio communications and radar systems in time and frequency domains along with the spatial domain. Integration in the spatial domain relies on a suitable beamforming technique for acquiring desired detection performance levels for both operations. Beamforming methods in the context of JCAS systems, with an emphasis on convex optimization, are studied in this thesis. A previously established work on beamformer design for optimum antenna selection is reviewed and duplicated to establish the groundwork for the main research. The novel beamforming algorithm proposed in this work maximizes the detection performance for the radar function in a JCAS system while maintaining the communication performance at an acceptable level. This is accomplished in the presence of clutter and with no assumption of a direct path between the transmitter and the communication user. A mathematical groundwork is presented for acquiring a valid convex optimization problem to represent the beamforming objective and constraints, along with using rank one decomposition to convert the result into a beamforming weight vector usable in practical application. The tests performed on a simulation environment showed that performance tradeoffs between radar and communication functions are observable on acquired results, in addition to assurance about the validity of assumptions made during problem definition
Ergebnisse der Untersuchung des grönländischen Inlandeises mit dem elektromagnetischen Reflexionsverfahren in der Umgebung von NGRIP = Results from airborne radio-echosounding of the Greenland icesheet in the vicinity of NGRIP
Prenatalna identifikacija izolirane aberantne potključne arterije: je li potrebna daljnja genetska obrada?
The objective of this study was to evaluate the association between aberrant right
subclavian artery (ARSA) and chromosomal abnormalities. The study included 5211 women having
attended our unit for fetal anatomic screening and fetal echocardiography from August 2016 until
February 2019. After diagnosing ARSA, prenatal invasive testing was discussed with the patients.
ARSA affected fetus was determined in 57 cases; of these, there were 38 cases of isolated ARSA and
19 cases of non-isolated ARSA but associated with soft markers and fetal anomalies. Nineteen patients
underwent amniocentesis; Down syndrome was determined in two women, both of them from
the non-isolated ARSA group, with fetal hydrops, atrioventricular septal defect and esophageal atresia.
Fifteen of 38 patients who declined prenatal diagnostic testing, accepted karyotype analysis after delivery
and none of these 15 cases had chromosomal abnormalities. Identification of ARSA should be
followed by detailed ultrasound examination to ensure that there are no accompanying soft markers
and/or structural defects. Isolated ARSA may not be an indication for karyotype analysis or 22q11.2
microdeletions. Non-ARSA implies a strong predictor of aneuploidy, and when additional findings
are detected, invasive testing should be offered to the parents. The association between isolated ARSA
and genetic disease should be evaluated in large powered prospective studies.Cilj ovoga istraživanja bio je procijeniti udruženost aberantne desne potključne arterije (ADPA) i poremećaja kromosoma.
Istraživanje je obuhvatilo 5211 žena koje su posjetile našu jedinicu za anatomski probir i fetalnu ehokardiografiju od
kolovoza 2016. do veljače 2019. godine. Nakon što je dijagnosticirana ADPA sa ženama se razgovaralo o prenatalnom invazivnom
testiranju. Fetalna ADPA utvrđena je u 57 slučajeva, uključujući 38 slučajeva izolirane ADPA i 19 slučajeva ne-izolirane
ADPA, ali udružene s „mekim“ biljezima i fetalnim anomalijama. Devetnaest žena podvrgnuto je amniocentezi.
Downov sindrom utvrđen je kod dvije žene, obje iz skupine s ne-izoliranom ADPA, s fetalnim hidropsom, atrioventrikulskim
septalnim defektom i atrezijom jednjaka. Petnaest od 38 žena koje su odbile prenatalno dijagnostičko testiranje prihvatilo
je analizu kariotipa nakon porođaja i nijedna od njih nije imala kromosomne poremećaje. Nakon identificiranja ADPA
treba uslijediti podroban ultrazvučni pregled kako bismo bili sigurni da ne postoje prateći „meki“ biljezi i/ili strukturni defekti.
Izolirana ADPA ne mora biti indikacija za analizu kariotipa ili mikrodelecije 22q11.2. Ne-ADPA snažno upućuje na
aneuploidiju, a kad se dobiju dodatni nalazi tada treba roditeljima ponuditi invazivno testiranje. Udruženost izolirane ADPA
i genetske bolesti treba procijeniti u velikim i valjanim prospektivnim studijama
Chemosensory function in Wegener's granulomatosis: a preliminary report
Despite the fact that Wegener's granulomatosis affects the nasal and paranasal cavities and the cranial nerves regularly, chemosensory impairments have not been reported. The objective of this study is to test the three chemosensory systems, olfaction, taste, and intranasal trigeminal function in Wegener disease patients. We tested olfactory, gustatory, and intranasal trigeminal function in nine patients (5 women, 4 men, mean age 57years) with confirmed Wegener's granulomatosis. Olfaction was tested with the Sniffin'Sticks, gustatory function with the "Taste strips” and intranasal trigeminal function with a lateralization task. One patient had anosmia (11%), four patients had hyposmia (44%) and four patients were normosmic (45%). Gustatory testing function showed pathological taste strip results in five patients (55%) and normal results in three patients (33%). One patient did not undergo taste testing. Intranasal trigeminal function was lowered in five patients (56%) and normal in four patients (44%). Neither previous nasal surgery status nor endoscopic status was associated to a higher frequency in pathological scores for any of the three chemical senses. In conclusion, these preliminary results suggest a consistent affection in chemosensory functions in Wegener's granulomatosis patient
Optimal Joint Radar and Communications Beamforming for the Low-Altitude Airborne Vehicles in SAGIN
A symbolic feature that integrates the space, air and ground network components for service in challenging and remote areas is being envisaged with continuity and high mobility of the 6G mobile system. Simultaneously providing sensing and connectivity over the radio signal becomes essential to support the management of low-space air crafts in the mobile system with limited spectrum resources. In this paper, we investigate the optimal joint radar and communications beamforming scheme with the presence of the clutter to support the low-space airborne vehicles, e.g. unmanned aerial vehicles or drones that are essential components of Non-Terrestrial Networks. The proposed scheme achieves the optimal signal-to-clutter-plus-noise ratio of the sensing function while maintaining the performance of the predefined communications. The novel application of approximations and rank-reduction algorithms in this work maximizes the joint radar and communications performance, for a system model similar to the one that is solved with a local optimum solution in a previous work. The numeric simulation results show that our approach maintains low complexity while guaranteeing the global optimum beamforming solution.acceptedVersionPeer reviewe
Olfactory dysfunction in patients with primary progressive MS
OBJECTIVE: We tested the hypothesis that olfactory function is more impaired in patients with primary progressive MS (PPMS) than that in relapsing-remitting MS (RRMS). METHODS: Standardized olfactory testing was performed in 32 patients with PPMS, 32 patients with RRMS, and 32 healthy controls (HCs). Patients with olfactory dysfunction due to an alternative primary etiology were excluded. The validated olfactory testing method yielded individual scores for olfactory threshold, odor discrimination, and odor identification, along with a composite Threshold Discrimination Identification (TDI) score. RESULTS: Olfactory dysfunction was identified in 27 (84%) patients with PPMS, 10 (31%) patients with RRMS, and 1 (3%) HC. While age and sex were similar between PPMS and HCs, the TDI score and all olfactory subscores were significantly worse in patients with PPMS compared with HCs (all p < 0.001). After adjustment for differences in age, sex, Expanded Disability Status Scale (EDSS), and disease duration, odor discrimination, odor identification, and the composite TDI score were worse in patients with PPMS vs RRMS (p = 0.03, 0.04, and 0.02, respectively). Neither age, sex, EDSS, nor disease duration was significantly associated with the composite TDI score. CONCLUSIONS: Olfactory dysfunction was more frequent and severe in PPMS compared with RRMS, independent of disease duration and overall disability status. Further research on cellular level differences in olfactory neural pathways may lead to new insights about disease pathogenesis in MS
Longitudinal Testing of Olfactory and Gustatory Function in Patients with Multiple Sclerosis
Background The aim of the study was to investigate changes of the olfactory
and gustatory capacity in patients with multiple sclerosis (MS). Methodology
20 MS patients were tested longitudinally for 3 years after initial testing.
The Threshold Discrimination Identification test (TDI) was used for subjective
olfactometry. Objective olfactometry was performed by registering olfactory
evoked potentials (OEP) by EEG. The Taste Strip Test (TST) was used for
gustatory testing. Results 45% of the patients showed olfactory dysfunction in
the follow-up TDI test and 50% showed delayed OEP´s. 20% of the patients
showed gustatory dysfunction on follow-up visit. The patients showed mild
disease activity with 0,3 ± 0,5 relapses over the testing period and no
significant change of their olfactory and gustatory capacity. The olfactory
capacity for the discrimination of odors correlated inversely with the number
of relapses (r = -0.5, p ≤ 0.05). The patients were aware of their olfactory
deficit. Conclusions Olfactory and gustatory dysfunction is a symptom in MS
patients and may be a useful parameter to estimate disease progression in MS
patients. As the discrimination of odors is processed in higher central
regions of the central nervous system (CNS), the results suggest that
olfactory dysfunction could be due to CNS damage
Monitoring changes in biochemical and biomechanical properties of collagenous tissues using label-free and nondestructive optical imaging techniques
Reduced Mass and Diversity of the Colonic Microbiome in Patients with Multiple Sclerosis and Their Improvement with Ketogenic Diet
Background: Colonic microbiome is thought to be involved in auto-immune
multiple sclerosis (MS). Interactions between diet and the colonic microbiome
in MS are unknown. Methods: We compared the composition of the colonic
microbiota quantitatively in 25 MS patients and 14 healthy
controls.Fluorescence in situ hybridization (FISH) with 162 ribosomal RNA
derived bacterial FISH probes was used. Ten of the MS patients received a
ketogenic diet for 6 months. Changes in concentrations of 35 numerically
substantial bacterial groups were monitored at baseline and at 2, 12, and
23/24 weeks. Results: No MS typical microbiome pattern was apparent.The total
concentrations and diversity of substantial bacterial groups were reduced in
MS patients (P < 0.001). Bacterial groups detected with EREC (mainly
Roseburia), Bac303 (Bacteroides), and Fprau (Faecalibacterium prausnitzii)
probes were diminished the most. The individual changes were multidirectional
and inconsistent. The effects of a ketogenic diet were biphasic. In the short
term, bacterial concentrations and diversity were further reduced. They
started to recover at week 12 and exceeded significantly the baseline values
after 23–24 weeks on the ketogenic diet. Conclusions: Colonic biofermentative
function is markedly impaired in MS patients.The ketogenic diet normalized
concentrations of the colonic microbiome after 6 months
Persistierende Riechminderung nach COVID-19 – Empfehlungen der Arbeitsgemeinschaft Olfaktologie und Gustologie der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie e. V.
Der Artikel soll die existierende Literatur zu mit COVID-19 („coronavirus disease 2019“) assoziierten Riechstörungen nicht vollständig aufarbeiten, sondern die für die HNO-ärztliche Praxis relevanten Forschungserkenntnisse zusammenfassen sowie Empfehlungen zur Diagnostik und Therapie bei persistierenden Riechstörungen nach COVID-19 geben
- …