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Abstract Background At present, the diagnosis of acute coronary syndrome (ACS) can be made by emergency physicians using the usual complementary tests, since the current troponin and electrocardiogram (ECG) protocols have been extensively tested for their safety. However, the detection of coronary calcifications on CT associated with coronary obstruction may be of interest for the diagnostic strategy in the emergency department (ED). The aim of this study was to evaluate a strategy combining a non-ischemic ECG with an initial normal troponin assay and the diagnostic accuracy of chest CT in detecting coronary calcifications to rule out the presence of an acute coronary event in patients presenting with chest pain in the ED. Methods This was a retrospective, single-center study carried out in an ED in France and included all patients over 18 years of age presenting with chest pain between 1 June 2021 and 31 December 2021 with a non-ischemic ECG and a negative first troponin assay. The primary endpoint was the diagnostic performance of the combing strategy in ruling out ACS. The secondary endpoints were the sensitivity and specificity of calcifications in acute coronary syndrome, comparison with the diagnostic performance of a second troponin assay and the rate of reconsultation, rehospitalisation and investigations within 2 months of the ED. Results Of the 280 patients included, 141 didn’t have calcifications. A total of 14 events were found with a negative predictive value for the combining strategy of 99.8% [95%CI: 98.2 – 100]. Sensitivity and specificity were 98.4% [95%CI: 83.8 – 100] and 53% [95%CI: 47 – 58.9], respectively. Among patients with no calcification, 8.2% were admitted to hospital and none suffered an acute coronary event. A total of 36 patients (12.8%) consulted a doctor within 2 months, with 23 investigations, all of which were negative in the non-calcification group. Conclusions A strategy combining the detection of coronary calcifications on chest CT in patients with a non-ischemic ECG and a single troponin assay is effective to rule out ACS in the ED, and may perform better then ECG and troponin alone.

The progressing worldwide increases in tick occurrence and tick-borne diseases calls for the development of new prevention strategies to reduce their impact on human and animal health. Defining the risk of exposure to tick bites is therefore essential. Forestry workers are at high risk of tick bites. We set up an explorative study among forestry workers in the Alsace region in eastern France to measure the different factors affecting the risk of Ixodes ricinus tick bites during their activities in forests. For one year, forestry workers recorded the presence of ticks on their clothes and tick bites every time they were working in teams in different forest ecosystems. Questions about the prevention measures they followed were also noted. Among the 32 participants, we were able to differentiate between groups having a high, neutral, or low risk of being bitten. The median tick bite number per year was 4 (0–8). We tried to identify individual as well as environmental factors affecting the risk of tick bites. Factors influencing the risk were the seasonal peak of tick activity in May and June, the time of exposure, and the forest ecosystems visited during the year. Additional factors potentially affecting the risk were also identified.

This paper proposes a novel design and the experimental characterization of a dual-band, shared aperture transmitarray operating in dual linear polarization at K/Ka-band. It is based on a 1-bit unit-cell realized using five metal layers and demonstrating low transmission loss (< 2 dB). By combining the polarization rotation method and the stacked patch architecture, the proposed shared aperture transmitarray is able to shape the beam independently in both K- and Ka-bands. A $40\times 40$ -element prototype has been optimized by using an ad-hoc numerical tool and fabricated. The experimental results are in excellent agreement with the numerical and full-wave electromagnetic simulations. This flat lens is illuminated by two standard gain horns with a nominal gain of 10 dBi. They are mounted in orthogonal polarization and located at the same distance from the aperture (110 mm). A peak gain of 27.1 and 29.9 dBi has been achieved, respectively, at 18.7 and 28.5 GHz corresponding to an aperture efficiency of 26.1 and 22.3%. The possibility to steer mechanically the radiation pattern has also been experimentally proven. The proposed antenna system is a low-cost and compact solution for future vehicular broadband SatCom applications.

This work presents a full metal circularly-polarized lens-like antenna for Satcom applications at Ka-band. The antenna is composed of two continuous parallel plate waveguide (PPW) quasi-optical beamformers (QOBF), feeding an array of septum polarizers to generate circular polarization. The QOBFs operate over a wide band and provide a multi-beam coverage over a large field of view in the azimuthal plane, while maintaining a relatively simple mechanical design. The array of septum polarizers is based on a stepped profile to generate circular polarization with a good polarization purity in the uplink of Ka-band (27 - 31 GHz). The antenna is fully realized in aluminium. The antenna system provides 14 beams with alternating right/left handed circular polarization (RHCP/LHCP) with an axial ratio (AR) below 3 Db over an angular range of ±19° in the uplink of Ka-Band. The maximum gain in the azimuthal plane at 30 GHz is about 21 dB over the whole angular range, with a scan loss lower than 1.5 dB. The antenna efficiency is better than 78% for all beams in the operative band.

IntroductionIn the context of budgetary constraints faced by healthcare systems, the medical-economic evaluation of care strategies becomes essential. In particular, valuing consumed resources in the overcrowded emergency departments (EDs) has become a priority to adopt more efficient approaches in treating the growing number of patients. However, precisely measuring the cost of care is challenging. While bottom-up micro-costing is considered the gold standard, its practical application remains limited.ObjectiveThe objective was to accurately estimate the ED care cost for patients consulting in a French ED for suspected lower respiratory tract infection.MethodsThe authors conducted a cost analysis using a bottom-up micro-costing method. Patients were prospectively included between January 1, and March 31, 2023. The primary endpoint was the mean cost of ED care. Resources consumed were collected using direct observation method and cost data were obtained from information available at Strasbourg University Hospital.ResultsThe mean cost of ED care was €411.68 (SD = 174.49). The cost elements that made the greatest contribution to the total cost were laboratory tests, labor, latency time, imaging and consumables. Considering this cost and the current epidemiological data on respiratory infections in France, the absence of valuation for outpatient care represents an annual loss of over 17 million euros for healthcare facilities.ConclusionMicro-costing is a key element in valuing healthcare costs. The importance of accurately measuring costs, along with measuring the health outcomes of a defined care pathway, is to enhance the relevance of health economic evaluations and thus ensure efficient care.

Abstract Risk factors for long-term non-motor symptoms and quality of life following subthalamic nucleus deep brain stimulation (STN DBS) have not yet been fully identified. In the present study, we investigated the impact of motor symptom asymmetry in Parkinson’s disease. Data were extracted for 52 patients with Parkinson’s disease (half with predominantly left-sided motor symptoms and half with predominantly right-sided ones) who underwent bilateral STN and a matched healthy control group. Performances for cognitive tests, apathy and depression symptoms, as well as quality-of-life questionnaires at 12 months post-DBS were compared with a pre-DBS baseline. Results indicated a deterioration in cognitive performance post-DBS in patients with predominantly left-sided motor symptoms. Performances of patients with predominantly right-sided motor symptoms were maintained, except for a verbal executive task. These differential effects had an impact on patients’ quality of life. The results highlight the existence of two distinct cognitive profiles of Parkinson’s disease, depending on motor symptom asymmetry. This asymmetry is a potential risk factor for non-motor adverse effects following STN DBS.

A novel compact and highly efficient dual-polarized horn-like antenna is presented. It exploits a radiating aperture that is fed by four smaller waveguides via a quad-furcated junction. The antenna also comprises the full feed network for the feed waveguides including an integrated 4-way orthomode power divider. Design principles are described in detail and illustrated by means of an example involving an antenna with aperture size of 2.6 $\lambda _{0} \times 2.6\lambda _{0}$ ( $\lambda _{0}$ the wavelength at the central frequency of operation) intended primarily for Geostationary Orbit (GEO) satellites. The antenna feed was designed to comply with the Additive Manufacturing rules and exhibits aperture efficiency levels close to the theoretical maximum ones over the entire transmit Ku band (10.7 – 12.75 GHz), while at the same time its profile is highly compact (6.4 $\lambda _{0}$ ). The measured results of a prototype 3D-printed in Selective Laser Melting (SLM) verified experimentally the calculated high aperture efficiency (over 90%). The total antenna feed attains return loss > 19 dB and maximum cross-polarization isolation (XPI) > 24 dB over a bandwidth of 18%. In light of the favorable electrical performances and compact size, the proposed solution constitutes an appealing alternative to profiled (or spline) horns for satellite antenna systems used either as reflector feeds or direct radiating arrays.

The purpose of this work is to evaluate local power and electric field distributions inside high-resolution 3D anatomical CAD models of cutaneous appendages at 60 GHz upcoming for 5G/6G. The microscale resolution models of cutaneous nerves, lymphatics, pilosebaceous unit, microvasculature, eccrine sweat glands, Meissner corpuscle and Pacinian corpuscle were designed based on morphometric data and microscopic images. The Maxwell’s and Hanai’s mixture equations were employed to retrieve the complex permittivity of cutaneous appendages based on their free water content. The cutaneous appendages were exposed to a uniform plane wave. The finite element method was used to compute the power loss density (${\boldsymbol{PLD}}$) and internal electric field (${\boldsymbol{E}}$). The results indicate that the maximal ${\boldsymbol{PLD}}$ in cutaneous appendages occurred for ${\boldsymbol{E}}$ polarized along their longest dimension. Higher peak ${\boldsymbol{PLD}}$ was observed in high water content cutaneous appendages such as acrosyringium (45%), epidermal axon (37.9%), Pacinian corpuscle (32.5%), blood capillary (30.6%), lymph capillary (20%) and arrector pili muscle (13.5%) compared to the surrounding skin. Higher ${\boldsymbol{E}}$ was detected in low water content hair with the peak ${\boldsymbol{E}}$ 45.1% greater than in surrounding skin. The interfaces of the cutaneous appendages also manifested a boost (23.8%-60.9%) in ${\boldsymbol{PLD}}$ compared to the surrounding skin. Detailed physical interpretation of observed phenomena is provided in the article. These results provide an insight into microscale power deposition in skin at frequencies upcoming for wireless communications.

Background and Objectives: Chest radiography remains the most frequently used examination in emergency departments (ED) for the diagnosis of community-acquired pneumonia (CAP), despite its poor diagnostic accuracy compared with ultra-low-dose (ULD) chest computed tomography (CT). However, although ULD CT appears to be an attractive alternative to radiography, its organizational impact in ED remains unknown. Our objective was to compare the relevant timepoints in ED management of CT and chest radiography. Materials and Methods: We conducted a retrospective study in two ED of a University Hospital including consecutive patients consulting for a CAP between 1 March 2019 and 29 February 2020 to assess the organizational benefits of ULD chest CT and chest radiography (length of stay (LOS) in the ED, time of clinical decision after imaging). Overlap weights (OW) were used to reduce covariate imbalance between groups. Results: Chest radiography was performed for 1476 patients (mean age: 76 years [63; 86]; 55% men) and ULD chest CT for 133 patients (mean age: 71 [57; 83]; 53% men). In the weighted population with OW, ULD chest CT did not significantly alter the ED LOS compared with chest radiography (11.7 to 12.2; MR 0.96 [0.85; 1.09]), although it did significantly reduce clinical decision time (6.9 and 9.5 h; MR 0.73 [0.59; 0.89]). Conclusion: There is real-life evidence that a strategy with ULD chest CT can be considered to be a relevant approach to replace chest radiography as part of the diagnostic workup for CAP in the ED without increasing ED LOS.

Abstract Mm-wave dielectric waveguides are a promising and low-cost technology for the transmission of ultra-high data rates. Besides the attenuation (losses) and group delay, the bending loss of the dielectric waveguides is also one of the key parameters to establish the capacity and energy efficiency of such wired links, when deployed in realistic scenarios. In this context, we report the experimental characterizations of bending effects for various solid and hollow commercially available dielectric waveguides at V-band (50–75 GHz). A wide-band transition has been designed to carry out the measurements using a Vector Network Analyzer (VNA) and extension modules. The measured results are in very good agreement with full-wave simulations. Our experimental results show an average bending loss of 1.46 dB over the entire V-band for the fundamental $${HE}_{11}^{y}$$ HE 11 y mode of a PTFE solid dielectric waveguide (core diameter of 3.06 mm) with a 90° bending angle and 25 mm radius of curvature. This value rises up to 2.88 dB (or 3.25 dB) when bending radius is changed to 15 mm (or bending angle grows up to 140°). The measurements also show that the measured bending losses increase significantly for hollow dielectric waveguides, in particular when the inner to outer diameter ratio gets larger.

Abstract The scattering and absorption of the H‐polarised wave by a finite number of graphene strips embedded into a grounded dielectric slab is considered in the terahertz frequency range. The rigorous and efficient method of singular integral equations is used here. The discretisation is based on the convergent meshless Nystrom‐type algorithm. Graphene is modelled as a zero thickness layer with a complex conductivity obtained from the Kubo formalism. Dependences of the total scattering cross section, including the part that is associated with dielectric slab guided waves, and absorption cross section as well as near field patterns are studied. The behaviour of the scattering and absorption characteristics is explained in terms of resonances on the natural modes supported by the studied structure. Special attention is paid to the excitation of the dielectric waveguide eigenwaves near the grating‐mode resonances.

Among the cognitive symptoms that are associated with Parkinson's disease (PD), alterations in cognitive action control (CAC) are commonly reported in patients. CAC enables the suppression of an automatic action, in favor of a goal-directed one. The implementation of CAC is time-resolved and arguably associated with dynamic changes in functional brain networks. However, the electrophysiological functional networks involved, their dynamic changes, and how these changes are affected by PD, still remain unknown. In this study, to address this gap of knowledge, 10 PD patients and 10 healthy controls (HC) underwent a Simon task while high-density electroencephalography (HD-EEG) was recorded. Source-level dynamic connectivity matrices were estimated using the phase-locking value in the beta (12-25 Hz) and gamma (30-45 Hz) frequency bands. Temporal independent component analyses were used as a dimension reduction tool to isolate the task-related brain network states. Typical microstate metrics were quantified to investigate the presence of these states at the subject-level. Our results first confirmed that PD patients experienced difficulties in inhibiting automatic responses during the task. At the group-level, we found three functional network states in the beta band that involved fronto-temporal, temporo-cingulate and fronto-frontal connections with typical CAC-related prefrontal and cingulate nodes (e.g., inferior frontal cortex). The presence of these networks did not differ between PD patients and HC when analyzing microstates metrics, and no robust correlations with behavior were found. In the gamma band, five networks were found, including one fronto-temporal network that was identical to the one found in the beta band. These networks also included CAC-related nodes previously identified in different neuroimaging modalities. Similarly to the beta networks, no subject-level differences were found between PD patients and HC. Interestingly, in both frequency bands, the dominant network at the subject-level was never the one that was the most durably modulated by the task. Altogether, this study identified the dynamic functional brain networks observed during CAC, but did not highlight PD-related changes in these networks that might explain behavioral changes. Although other new methods might be needed to investigate the presence of task-related networks at the subject-level, this study still highlights that task-based dynamic functional connectivity is a promising approach in understanding the cognitive dysfunctions observed in PD and beyond.

We explore the use of a new modulated metasurface (MTS) antenna topology as solution for wireless backhaul at K band. The proposed structure is composed of a quasi-optical beamformer, which feeds the modulated MTS radiating aperture. These two elements are vertically stacked in a two-layer pillbox architecture to produce a very compact antenna. Furthermore, our design is able to provide several beams at different pointing angles and, hence, it offers the possibility of discrete beam steering by beam switching. The employment of a modulated MTS and the compactness given by the pillbox approach lead to a high-gain and low-profile antenna that could be an appealing solution for mobile backhaul networks.

This paper presents a method for synthesizing metallic horns capable of radiating highly localized electromagnetic pulses, known as X-waves. The proposed method is based on a mode-matching framework for shaped horns. The aperture field distribution required to generate X-waves is synthesized by mode conversion. The near-field horns generated by this method are full-metal structures radiating X-waves in a wide range of frequencies with low dispersion. The obtained structures may be scaled to any frequency range, and they are particularly suited to millimeter and sub-millimeter wave applications. We validate the concept by presenting a horn capable of radiating X-waves over a 44% fractional bandwidth (FBW) with a 5° dispersion of the axicon angle. Capabilities and limitations of this design procedure and the synthesized launchers are demonstrated, discussed, and compared with other state-of-the-art solutions.

With the fast development of 5th generation (5G) mobile networks and prominence of the personal area networks and human-centered communications, people of all ages are increasingly exposed in the upper part of the microwave spectrum. In some exposure scenarios, presence of a textile between the radiating source and skin can affect the power absorption. This study investigates, for the first time, the effect of ageing and impact of textile on the power deposition in a skin-equivalent model under near-field exposure induced by multi-beam radiating structures at 26 GHz and 60 GHz. An array of four Yagi antennas has been used as a representative example of 5G reconfigurable antennas. The maximum increase of the averaged absorbed power density with respect to the averaged value for adults is observed at 70 year (8.8% at 26 GHz and 6.9% at 60 GHz). The strongest decrease is for 5-years-old children (-4.5% at 26 GHz and -3.7% at 60 GHz). In presence of a textile, the absorbed power density can increase or decrease depending on the textile properties (thickness and permittivity) and on the thickness of the air gap between textile and skin. With cotton and wool (considered as representative textile materials) the maximum increase of the averaged absorbed power density is about 40% compared to the bare skin.

The aim of this study was to investigate quantitatively local sub-cellular power deposition at frequencies upcoming for wireless power transfer (WPT) and millimeter-wave (mmWave) technologies. The study was performed on a realistic two-dimensional keratinocyte cell model, designed based on electron microscopy images and experimental data on surface area fraction of keratinocyte to explicitly represent nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus and vesicles. The average power loss density (${\boldsymbol{PLD_{\text{avg}}}}$) and electric field (${\boldsymbol{E_{\text{avg}}}}$) were computed by solving Laplace's equation under quasi-static approximation using the finite element method. The numerical results for the spherical cell model were validated with corresponding analytical solutions. The results showed that ${\boldsymbol{E_{\text{avg}}}}$ and ${\boldsymbol{PLD_{\text{avg}}}}$ inside the organelles increased with frequency. Nearly, 51.8% and 98.9% of the incident field on the cell penetrated inside the organelles at 6.78 MHz and 60 GHz, respectively. The ${\boldsymbol{PLD_{\text{avg}}}}$ within the organelles in average was 35.7% (6.78 MHz) and 1.95% (60 GHz) lower than in the cytoplasm. The ${\boldsymbol{E_{\text{avg}}}}$ induced inside nuclear pores (N$_\text{p}$) exceeded the incident field by 5 times and 1.1 times at 6.78 MHz and 60 GHz, respectively. The corresponding ${\boldsymbol{PLD_{\text{avg}}}}$ within N$_\text{p}$ was 32.7 times (6.78 MHz) and 1.2 times (60 GHz) higher than that of the cytoplasm. The enhancement of ${\boldsymbol{PLD_{\text{avg}}}}$ in N$_\text{p}$ suggests that the intracellular traffic is locally exposed to higher exposure levels compared to the background ${\boldsymbol{PLD_{\text{avg}}}}$ in cytosol.

Abstract Background Acute respiratory distress syndrome continues to drive significant morbidity and mortality after severe trauma. The incidence of trauma-induced, moderate-to-severe hypoxaemia, according to the Berlin definition, could be as high as 45%. Its pathophysiology includes the release of damage-associated molecular patterns (DAMPs), which propagate tissue injuries by triggering neutrophil extracellular traps (NETs). NETs include a DNA backbone coated with cytoplasmic proteins, which drive pulmonary cytotoxic effects. The structure of NETs and many DAMPs includes double-stranded DNA, which prevents their neutralization by plasma. Dornase alfa is a US Food and Drug Administration-approved recombinant DNase, which cleaves extracellular DNA and may therefore break up the backbone of NETs and DAMPs. Aerosolized dornase alfa was shown to reduce trauma-induced lung injury in experimental models and to improve arterial oxygenation in ventilated patients. Methods TRAUMADORNASE will be an institution-led, multicentre, double-blinded, placebo-controlled randomized trial in ventilated trauma patients. The primary trial objective is to demonstrate a reduction in the incidence of moderate-to-severe hypoxaemia in severe trauma patients during the first 7 days from 45% to 30% by providing aerosolized dornase alfa as compared to placebo. The secondary objectives are to demonstrate an improvement in lung function and a reduction in morbidity and mortality. Randomization of 250 patients per treatment arm will be carried out through a secure, web-based system. Statistical analyses will include a descriptive step and an inferential step using fully Bayesian techniques. The study was approved by both the Agence Nationale de la Sécurité du Médicament et des Produits de Santé (ANSM, on 5 October 2018) and a National Institutional Review Board (CPP, on 6 November 2018). Participant recruitment began in March 2019. Results will be published in international peer-reviewed medical journals. Discussion If early administration of inhaled dornase alfa actually reduces the incidence of moderate-to-severe hypoxaemia in patients with severe trauma, this new therapeutic strategy may be easily implemented in many clinical trauma care settings. This treatment may facilitate ventilator weaning, reduce the burden of trauma-induced lung inflammation and facilitate recovery and rehabilitation in severe trauma patients. Trial registration ClinicalTrials.gov, NCT03368092 . Registered on 11 December 2017.

This paper presents the experimental results of a 2-bit electronically reconfigurable unit-cell for transmitarrays at Ka-band. The proposed unit-cell architecture is based on a six-metal layers design and three dielectric substrates. Two patch antennas are printed respectively on the top and bottom layers of the stack-up to achieve an antenna-filter-antenna structure. To implement the desired 2-bit phase resolution, two p-i-n diodes are bonded on each patch. The unit-cell has been fabricated and characterized in a specific waveguide simulator. The measurement results are compared to the simulated ones and show minimum transmission loss in the range 1.5 - 2.3 dB. The 3-dB fractional bandwidth is in the range 10.1 - 12.1%.

Abstract Millimeter wave (MMW)-induced heating represents a promising alternative for non-invasive hyperthermia of superficial skin cancer, such as melanoma. Pulsed MMW-induced heating of tumors allows for reaching high peak temperatures without overheating surrounding tissues. Herein, for the first time, we evaluate apoptotic and heat shock responses of melanoma cells exposed in vitro to continuous (CW) or pulsed-wave (PW) amplitude-modulated MMW at 58.4 GHz with the same average temperature rise. Using an ad hoc exposure system, we generated 90 min pulse train with 1.5 s pulse duration, period of 20 s, amplitude of 10 °C, and steady-state temperature at the level of cells of 49.2 °C. The activation of Caspase-3 and phosphorylation of HSP27 were investigated using fluorescence microscopy to monitor the spatial variation of cellular response. Our results demonstrate that, under the considered exposure conditions, Caspase-3 activation was almost 5 times greater following PW exposure compared to CW. The relationship between the PW-induced cellular response and SAR-dependent temperature rise was non-linear. Phosphorylation of HSP27 was 58% stronger for PW compared to CW. It exhibits a plateau for the peak temperature ranging from 47.7 to 49.2 °C. Our results provide an insight into understanding of the cellular response to MMW-induced pulsed heating.