Holographic mixed reality for planning transcatheter aortic valve replacement.

BACKGROUND: Using three-dimensional (3D) modalities for optimal pre-procedure planning in transcatheter aortic valve replacement (TAVR) is critical for procedural success. However, current methods rely on visualizing images on a two-dimensional screen, using shading and colors to create the illusion of 3D, potentially impeding the accurate comprehension of the actual anatomy structures. In contrast, a new Mixed Reality (MxR) based software enables accurate 3D visualization, imaging manipulation, and quantification of measurements. AIMS: The study aims to evaluate the feasibility, reproducibility, and accuracy of dimensions of the aortic valve complex as measured with a new holographic MxR software (ARTICOR®, Artiness srl, Milano, Italy) compared to a widely used software for pre-operative sizing and planning (3mensio Medical Imaging BV, Bilthoven, The Netherlands) . METHODS: This retrospective, observational, double-center study enrolled 100 patients with severe aortic stenosis who underwent cardiac computed tomography (CCT) before TAVR. The CCT datasets of volumetric aortic valve images were analyzed using 3Mensio and newly introduced MxR-based software. RESULTS: 98% of the CCT datasets were successfully converted into holographic models. A higher level of agreement between the two software systems was observed for linear metrics (short, long, and average diameter). In comparison, agreement was lower for area, perimeter, and annulus-to-coronary ostia distance measurements. Notably, the annulus area, annular perimeter, LVOT area, and LVOT perimeter were significantly and consistently smaller with the MxR-based software compared to the 3Mensio. Excellent interobserver reliability was demonstrated for most measurements, especially for direct linear measurements. CONCLUSIONS: Linear Measurements of the aortic valve complex using MxR-based software are reproducible compared to the standard CCT dataset analyzed with 3Mensio. MxR-based software could represent an accurate tool for the pre-procedural planning of TAVR.

Exploring the Relationship between Subcutaneous Fat Index and Neck Pain in Patients with Spinal Cervical Spondylosis: A Retrospective Cohort Study.

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVES: This study measures the subcutaneous fat index (SFI) of the cervical spine in patients with spinal cervical spondylosis using cervical magnetic resonance imaging (MRI) and explores its relationship with neck pain in patients with spinal cervical spondylosis. METHODS: In this single-center retrospective study, 298 patients hospitalized for spinal cervical spondylosis between January and June 2021 were initially considered. After applying inclusion and exclusion criteria, 93 patients were enrolled. The cervical MRI data for these patients were analyzed using A-Site software. The SFI was measured at the median sagittal plane on T2-weighted images. Patients were categorized into two groups based on their admission complaints: those with cervical pain and those without it. Differences between these groups were then statistically analyzed. RESULTS: The mean SFIs with standard deviations for the neck and non-neck pain groups were 36.4%±7.7% and 27.0%±7.9%, respectively, with a significant difference (P<0.0001). The SFI was consistently higher across all neck segments in the neck pain group compared to the non-neck pain group (P<0.05). The two groups had no statistically significant difference in the body mass index (BMI). CONCLUSIONS: The SFI provides a more precise assessment of muscle and fat distribution in the posterior cervical region than BMI and is generally higher in patients with spinal cervical spondylosis who experience neck pain. These findings suggest the importance of early functional exercises post-surgery for potentially improving surgical outcomes in this patient population.

Low-Cost Hourly Ambient Black Carbon Measurements at Multiple Cities in Africa.

There is a notable lack of continuous monitoring of air pollutants in the Global South, especially for measuring chemical composition, due to the high cost of regulatory monitors. Using our previously developed low-cost method to quantify black carbon (BC) in fine particulate matter (PM2.5) by analyzing reflected red light from ambient particle deposits on glass fiber filters, we estimated hourly ambient BC concentrations with filter tapes from beta attenuation monitors (BAMs). BC measurements obtained through this method were validated against a reference aethalometer between August 2 and 23, 2023 in Addis Ababa, Ethiopia, demonstrating a very strong agreement (R2 = 0.95 and slope = 0.97). We present hourly BC for three cities in sub-Saharan Africa (SSA) and one in North America: Abidjan (Côte d'Ivoire), Accra (Ghana), Addis Ababa (Ethiopia), and Pittsburgh (USA). The average BC concentrations for the measurement period at the Abidjan, Accra, Addis Ababa Central summer, Addis Ababa Central winter, Addis Ababa Jacros winter, and Pittsburgh sites were 3.85 µg/m3, 5.33 µg/m3, 5.63 µg/m3, 3.89 µg/m3, 9.14 µg/m3, and 0.52 µg/m3, respectively. BC made up 14-20% of PM2.5 mass in the SSA cities compared to only 5.6% in Pittsburgh. The hourly BC data at all sites (SSA and North America) show a pronounced diurnal pattern with prominent peaks during the morning and evening rush hours on workdays. A comparison between our measurements and the Goddard Earth Observing System Composition Forecast (GEOS-CF) estimates shows that the model performs well in predicting PM2.5 for most sites but struggles to predict BC at an hourly resolution. Adding more ground measurements could help evaluate and improve the performance of chemical transport models. Our method can potentially use existing BAM networks, such as BAMs at U.S. Embassies around the globe, to measure hourly BC concentrations. The PM2.5 composition data, thus acquired, can be crucial in identifying emission sources and help in effective policymaking in SSA.

Low-dose, standard, and high-resolution cone beam computed tomography for alveolar bone measurements related to implant planning: An ex vivo study in human specimens.

AIM: To evaluate the performance of low-dose cone beam computed tomography (CBCT) protocols with regard to linear bone measurements in the posterior mandible for implant planning compared with higher dose protocols. MATERIALS AND METHODS: Forty-two edentulous posterior sites in human cadaveric mandibles were imaged in three CBCT scanners using three or four protocols with varying exposure parameters to achieve lower dose. Co-registration was performed to generate sagittal and cross-sectional image sections representative of the implant site. Three observers measured bone height, from the alveolar crest to the mandibular canal, and width, three mm from the top of the alveolar crest. Intra- and interobserver reproducibility were assessed for the cases rated as nonmeasurable as well as for completed measurements. The measurements were analyzed using paired t-tests for differences among the CBCT protocols and the frequency distribution of nonmeasurable cases with a Pearson Chi-square test. RESULTS: Reproducibility for registering nonmeasurable cases varied among observers; however, no consistent significant differences were found in the frequency distribution of these cases among observers, units, and protocols. Intraclass correlation coefficients (ICC) were >0.9 for all measurements of bone height and width. Mean differences of <0.5 mm were found regardless of protocol; however, one observer did in some cases produce larger differences. CONCLUSION: Linear bone measurements did not differ significantly and could be performed with excellent reliability, using low-dose CBCT protocols compared with standard and high-resolution ones. Varying approaches for rating nonmeasurable cases were found, indicating differences in diagnostic strategies related to implant planning among observers.

Effects of a physical exercise programme on bodyweight, body condition score and chest, abdominal and thigh circumferences in dogs.

BACKGROUND: Research on the effects of physical exercise on canine body composition is limited. The aim of this study was to investigate the effects of a physical exercise programme on bodyweight, body condition score (BCS) and chest, abdominal and thigh circumferences in dogs. Twenty-one healthy dogs of different breeds exercised together with their owners during an eight-week programme consisting of jogging and strength exercises. Standardised measurements were performed in triplicates with a measuring tape on standing dogs. Chest circumference was measured at three anatomical locations, abdomen at two and thigh at one. Data on bodyweight, BCS (9-point scale) and circumferences were analysed with mixed model repeated measures analyses to evaluate changes after the programme and effects of target distance. RESULTS: Seven dog owners choose a target distance of 2 km and 14 owners choose 5-10 km. Mean BCS decreased (P = 0.007) after the programme (5.1 ± 0.9 vs. 4.7 ± 0.6) but there was no effect of target distance. Almost all chest and abdominal circumference measurements decreased (P ≤ 0.007) with the 2 km group driving the reduction in chest circumference and the 5-10 km group driving the reduction in abdominal circumference. In contrast, thigh circumference (28.8 ± 0.4 vs. 30.2 ± 0.4) increased (P = 0.007) while bodyweight was maintained. There were positive correlations between BCS and abdominal/chest ratios before and after the programme (Pearson correlation; R square ≤ 0.43, P ≤ 0.0012) but the mean ratio remained constant. CONCLUSIONS: Results indicated a redistribution between total body fat and muscle mass in body composition of normal weight to slightly overweight dogs after the physical exercise programme. The use of bodyweight alone was not a reliable evaluation method to complement the BCS assessment. However, repeated measurements of chest, abdominal and thigh circumference might aid in the assessment of body composition in dogs performing physical exercise. Further research should include a control group and objective evaluations of total body fat and lean mass, in order to investigate the effectiveness of physical exercise as a freestanding method for decreasing BCS and increasing muscle mass in overweight dogs.

Exploring surface charge dynamics: implications for AFM height measurements in 2D materials.

An often observed artifact in atomic force microscopy investigations of individual monolayer flakes of 2D materials is the inaccurate height derived from topography images, often attributed to capillary or electrostatic forces. Here, we show the existence of a Joule dissipative mechanism related to charge dynamics and supplementing the dissipation due to capillary forces. This particular mechanism arises from the surface conductivity and assumes significance specially in the context of 2D materials on insulating supports. In such scenarios, the oscillating tip induces in-plane charge currents that in many circumstances constitute the main dissipative contribution to amplitude reduction and, consequently, affect the measured height. To investigate this phenomenon, we conduct measurements on monolayer flakes of co-deposited graphene oxide and reduced graphene oxide. Subsequently, we introduce a general model that elucidates our observations. This approach offers valuable insights into the dynamics of surface charges and their intricate interaction with the tip.

Influence of age, sex, bodyweight, and training on echocardiographic measurements in healthy mixed-breed donkeys.

The donkey has always been a notable working animal and its importance as a companion animal has been growing over the last few years. However, there are only a few studies about cardiology in this species. Therefore, this study aimed to evaluate the influence of age, sex, training, and bodyweight on cardiac dimension in mixed-breed donkeys. Forty-five clinically and para-clinically healthy mixed-breed donkeys were included, and B-mode and M-mode echocardiographic measurements were recorded. Multivariate linear regression analysis was performed to identify the effect of age, sex, bodyweight, and training on cardiac measurements. Most of the echocardiographic measurements showed a strong statistically significant correlation with bodyweight. Linear regression analysis between echocardiographic measurements and bodyweight was performed to obtain the values of the intercept and slope of the linear equation to calculate the echocardiographic measurements as a function of bodyweight. This is the first study reporting a strong linear correlation between echocardiographic measurements and bodyweight and reporting a correlation between training and echocardiographic parameters in donkeys, suggesting that this variable should be considered when assessing cardiac dimensions in these animals.

Tomographic three-dimensional ultrasound imaging improves spatial visualization and management of varicose veins.

Tomographic three-dimensional ultrasound using handsfree electromagnetic tracking is an important adjunct to traditional two-dimensional duplex ultrasound examination. This technique allows vascular surgeons to better orientate and visualize the often complex anatomy along the entire length of the target vein. This paper reports a novel technique in preoperative and postoperative acquisition of superficial incompetent veins, thereby providing a comprehensive three-dimensional orientation of different pathological patterns of incompetence.

Therapeutic alliance in individual adult psychotherapy: a systematic review of conceptualizations and measures for face-to-face- and online-psychotherapy.

Background: The therapeutic alliance (TA) is a robust and pantheoretical predictor of treatment outcome in Face-to-Face- (F2F-) and Online-psychotherapy (Online-PT). Many authors have proposed several conceptualizations of TA, which are oftentimes operationalized. The resulting diversity of conceptualizations and measures is presented in this review. Methods: We performed a three-parted literature search for self-report-instruments of TA in individual, voluntary F2F-PT with adults (1. utilization of past reviews, 2. systematic literature search yielding 5,205 articles, 3. reference lists). Analogously, we conducted a systematic literature search for instruments of TA in the Online-setting (yielding 200 articles). Additionally, we analyzed the content of the instruments qualitatively. Results: A current overview of 48 instruments for measuring TA (46 for F2F-PT, 2 for Online-PT) including their conceptual backgrounds, characteristics and main content aspects is presented. Most instruments (n = 24) operationalize one or more theoretical conceptualizations of TA. Other instruments are adaptation/syntheses of existing measures (n = 14), based on literature searches (n = 3) or on an empirical survey (n = 3) and two instruments provide no conceptual background information. The content of the instruments mainly focused on the following aspects: 1. Self-disclosure and authenticity; 2. Agreement; 3. Active participation, motivation and compliance; 4. Trust and secure attachment; and 5. Considering needs/abilities/wishes of the patient. Additionally, a narrative review of various approaches to conceptualize TA is presented and linked to respective corresponding instruments. Discussion: The broad variety of conceptualizations and measures of TA makes coherent research on TA difficult. There are conceptual challenges such as the role of attachment style in TA that remain to be clarified. The current conceptualizations and measures do not incorporate the practical experience and expertise of psychotherapists and patients sufficiently. A metatheoretical conceptualization and measure of TA based on an empirical survey of psychotherapists and patients could address these issues.

Automated weight-bearing foot measurements using an artificial intelligence-based software.

OBJECTIVE: To assess the accuracy of an artificial intelligence (AI) software (BoneMetrics, Gleamer) in performing automated measurements on weight-bearing forefoot and lateral foot radiographs. METHODS: Consecutive forefoot and lateral foot radiographs were retrospectively collected from three imaging institutions. Two senior musculoskeletal radiologists independently annotated key points to measure the hallux valgus, first-second metatarsal, and first-fifth metatarsal angles on forefoot radiographs and the talus-first metatarsal, medial arch, and calcaneus inclination angles on lateral foot radiographs. The ground truth was defined as the mean of their measurements. Statistical analysis included mean absolute error (MAE), bias assessed with Bland-Altman analysis between the ground truth and AI prediction, and intraclass coefficient (ICC) between the manual ratings. RESULTS: Eighty forefoot radiographs were included (53 ± 17 years, 50 women), and 26 were excluded. Ninety-seven lateral foot radiographs were included (51 ± 20 years, 46 women), and 21 were excluded. MAE for the hallux valgus, first-second metatarsal, and first-fifth metatarsal angles on forefoot radiographs were respectively 1.2° (95% CI [1; 1.4], bias = - 0.04°, ICC = 0.98), 0.7° (95% CI [0.6; 0.9], bias = - 0.19°, ICC = 0.91) and 0.9° (95% CI [0.7; 1.1], bias = 0.44°, ICC = 0.96). MAE for the talus-first, medial arch, and calcaneal inclination angles on the lateral foot radiographs were respectively 3.9° (95% CI [3.4; 4.5], bias = 0.61° ICC = 0.88), 1.5° (95% CI [1.2; 1.8], bias = - 0.18°, ICC = 0.95) and 1° (95% CI [0.8; 1.2], bias = 0.74°, ICC = 0.99). Bias and MAE between the ground truth and the AI prediction were low across all measurements. ICC between the two manual ratings was excellent, except for the talus-first metatarsal angle. CONCLUSION: AI demonstrated potential for accurate and automated measurements on weight-bearing forefoot and lateral foot radiographs.

Stellated cuboctahedron of FeIII.

The solvothermal reaction of FeCl2·4H2O and H4TBC[4] in a basic dmf/EtOH solution affords an [FeIII18] Keplerate conforming to a stellated cuboctahedron. Magnetic measurements reveal spin frustration effects arising from the high symmetry.

Validation of a Novel Noninvasive Technology to Estimate Blood Oxygen Saturation Using Green Light: Observational Study.

BACKGROUND: Pulse oximeters work within the red-infrared wavelengths. Therefore, these oximeters produce erratic results in dark-skinned subjects and in subjects with cold extremities. Pulse oximetry is routinely performed in patients with fever; however, an elevation in body temperature decreases the affinity of hemoglobin for oxygen, causing a drop in oxygen saturation or oxyhemoglobin concentrations. OBJECTIVE: We aimed to determine whether our new investigational device, the Shani device or SH1 (US Patent 11191460), detects a drop in oxygen saturation or a decrease in oxyhemoglobin concentrations. METHODS: An observational study (phase 1) was performed in two separate groups to validate measurements of hemoglobin and oxygen concentrations, including 39 participants recruited among current university students and staff aged 20-40 years. All volunteers completed baseline readings using the SH1 device and the commercially available Food and Drug Administration-approved pulse oximeter Masimo. SH1 uses two light-emitting diodes in which the emitted wavelengths match with absorption peaks of oxyhemoglobin (hemoglobin combined with oxygen) and deoxyhemoglobin (hemoglobin without oxygen or reduced hemoglobin). Total hemoglobin was calculated as the sum of oxyhemoglobin and deoxyhemoglobin. Subsequently, 16 subjects completed the "heat jacket study" and the others completed the "blood donation study." Masimo was consistently used on the finger for comparison. The melanin level was accounted for using the von Luschan skin color scale (VLS) and a specifically designed algorithm. We here focus on the results of the heat jacket study, in which the subject wore a double-layered heated jacket and pair of trousers including a network of polythene tubules along with an inlet and outlet. Warm water was circulated to increase the body temperature by 0.5-0.8 °C above the baseline body temperature. We expected a slight drop in oxyhemoglobin concentrations in the heating phase at the tissue level. RESULTS: The mean age of the participants was 24.1 (SD 0.8) years. The skin tone varied from 12 to 36 on the VLS, representing a uniform distribution with one-third of the participants having fair skin, brown skin, and dark skin, respectively. Using a specific algorithm and software, the reflection ratio for oxyhemoglobin was displayed on the screen of the device along with direct hemoglobin values. The SH1 device picked up more minor changes in oxyhemoglobin levels after a change in body temperature compared to the pulse oximeter, with a maximum drop in oxyhemoglobin concentration detected of 6.5% and 2.54%, respectively. CONCLUSIONS: Our new investigational device SH1 measures oxygen saturation at the tissue level by reflectance spectroscopy using green wavelengths. This device fared well regardless of skin color. This device can thus eliminate racial disparity in these key biomarker assessments. Moreover, since the light is shone on the wrist, SH1 can be readily miniaturized into a wearable device.

No effects of post-activation performance enhancement in elite male volleyball players under complex training.

The aim of this study was to establish reliability of post-activation performance enhancement in three manners: (1) interday morning and afternoon reliability; (2) intraday morning and afternoon reliability; (3) intraday set-to-set reliability. Twelve elite male volleyball players experienced in resistance training performed four identical experimental sessions-two in the morning and two in the afternoon. During each session participants performed a mini complex training session-three sets of a conditioning activity (CA) (3 repetitions of a trap bar deadlift at 80% 1RM with 15% of accommodating resistance) and 90 s after a CA performed squat jump (SJ) with 4 min intra-set rest interval. The ANOVA with repeated measures was used to assess significance of the effect of a CA and ICC to assess reliability of measurements. The PAPE protocol was found to be ineffective to subsequently enhance JH on various occasions. Also, the results of this study suggest that the practitioners may effectively implement appropriately organized complex training as both intraday set-to-set (0.87 and 0.82 for morning sessions; 0.83 and 0.58 for afternoon sessions) and interday morning (0.67) and afternoon (0.8) reliabilities seem to be acceptable. However, introducing two CT sessions within one day is highly questionable as at the moment intraday morning and afternoon reliability is vague (0.88 and 0.48).

Microstructural and Electrochemical Study: Pitting Corrosion Mechanism on A390 Al-Si Alloy and Ce-Mo Treatment as a Better Corrosion Protection.

Sulfuric acid anodizing assisted by a hydrothermal sealing with inhibitors [Ce3+-Mo6+] was used to prevent pitting corrosion on spray-deposited hypereutectic Al-Si alloy (A390). An investigation concerning the evaluation of pitting corrosion resistance on the anodic oxide thin film with ions incorporated was carried out in NaCl solution using electrochemical measurements (i.e., potentiodynamic polarization and electrochemical impedance spectroscopy, EIS). The influence of Si phase morphology and size on the growth mechanism of an anodic oxide film was characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results were then compared with those for its equivalent IM390 alloy (Al-17Si-4.5Cu-0.6Mg) produced through a conventional process ingot metallurgy, IM. The electrochemical findings indicate that sulfuric acid anodizing followed by a simple hot water sealing treatment was ineffective. In this manner, an intense attack was localized by pitting corrosion that occurred on the anodic oxide film in less than three days, as denoted by characteristic changes in the EIS spectra at the lowest frequencies. Improved results were achieved for Ce-Mo surface modification, which can provide better corrosion resistance on the aluminum alloys because no signs of pits were observed during the corrosion testing.

An Intraoperative Method to Minimize Leg Length Discrepancy in Anterior Minimally Invasive Total Hip Arthroplasty-A Prospective Study.

While several intraoperative devices have been described in the literature for assessing leg length discrepancy (LLD), none have been utilized during total hip arthroplasty (THA) performed via the Anterior Minimally Invasive Surgery (AMIS) approach. The aim of this prospective study was to evaluate the efficacy and accuracy of a compass device in assessing leg length during THA performed using the AMIS technique. A prospective study was conducted involving 35 patients who consecutively underwent unilateral primary THA using the AMIS technique at our department from September 2017 to December 2018. LLD was measured by comparing preoperative and postoperative anteroposterior radiographs of the pelvis, independently assessed by two observers. The mean preoperative LLD was 3.6 (SD 3.9, range, 0.2-19.3) mm. The mean postoperative LLD was 2.5 (SD 3.0, range, 0-12.2) mm. A postoperative LLD of less than 5 mm was observed in 88.2% of cases, with 94.1% having values less than 10 mm. In conclusion, the compass device emerged as a valuable tool for ensuring precise limb length control in THA with the AMIS approach, offering both efficiency and cost-effectiveness in clinical practice.

Evaluating the Impact of Reminiscence Therapy on Cognitive and Emotional Outcomes in Dementia Patients.

This study examines the impact of reminiscence therapy on cognitive and emotional well-being in institutionalized older patients with dementia. Conducted at the Long-Term Care Health Facility for the Elderly, the research involved 34 participants who underwent therapy sessions that included personalized discussions of past experiences. Using physiological markers such as electroencephalography alpha and beta waves, along with psychological measures such as the Hasegawa Dementia Scale-Revised, the study aimed to quantify the effects of the therapy. Although the results indicated positive correlations between alpha and beta waves, suggesting enhanced relaxation and cognitive engagement, improvements in Hasegawa Dementia Scale-Revised scores were not statistically significant, pointing to variability in therapeutic effectiveness among patients. Despite these mixed outcomes, the findings support the potential of reminiscence therapy as a non-pharmacological intervention to improve the quality of life of dementia patients, though they also underscore the necessity for further research to refine therapy protocols and enhance applicability.

Service Life of Pre-Tensioned Concrete Structures in a Chloride Environment on the Example of an Aluminium Foundry Building.

This paper describes a study of the chloride content in the concrete lagging of prestressed concrete elements of the roof structure of an aluminium foundry building. Sources of chloride pollution in industrial facilities are discussed. Methods for collecting dust deposited on the structure and sampling concrete for chloride concentration testing are presented in detail. The test methods used and the apparatus used to assess the chloride content at the thickness of concrete reinforcement lagging are presented. Investigations of the chloride content in the concrete of the reinforcement cover showed a very high concentration of chloride in the near-surface layer, depending on the location of the element in relation to the source of chloride emission into the environment. In contrast, the concrete of the deeper layers of the lagging contained very small amounts of Cl- chlorides. The results of the chloride content of the lagging concrete were plotted against the distance from the surface of the specimen and approximated by the function C(x,t) based on Fick's second law and its solution. A satisfactory fit of the course of this function to the experimental results was obtained. Based on the obtained C(x,t) function, the durability of the main structural components of an aluminium foundry industrial hall operating in a chloride environment was estimated.

Separation of Damage Mechanisms in Full Forward Rod Extruded Case-Hardening Steel 16MnCrS5 Using 3D Image Segmentation.

In general, formed components are lightweight as well as highly economic and resource efficient. However, forming-induced ductile damage, which particularly affects the formation and growth of pores, has not been considered in the design of components so far. Therefore, an evaluation of forming-induced ductile damage would enable an improved design and take better advantage of the lightweight nature as it affects the static and dynamic mechanical material properties. To quantify the amount, morphology and distribution of the pores, advanced scanning electron microscopy (SEM) methods such as scanning transmission electron microscopy (STEM) and electron channeling contrast imaging (ECCI) were used. Image segmentation using a deep learning algorithm was applied to reproducibly separate the pores from inclusions such as manganese sulfide inclusions. This was achieved via layer-by-layer ablation of the case-hardened steel 16MnCrS5 (DIN 1.7139, AISI/SAE 5115) with a focused ion beam (FIB). The resulting images were reconstructed in a 3D model to gain a mechanism-based understanding beyond the previous 2D investigations.

A Critical Review of the Propagation Models Employed in LoRa Systems.

LoRa systems are emerging as a promising technology for wireless sensor networks due to their exceptional range and low power consumption. The successful deployment of LoRa networks relies on accurate propagation models to facilitate effective network planning. Therefore, this review explores the landscape of propagation models supporting LoRa networks. Specifically, we examine empirical propagation models commonly employed in communication systems, assessing their applicability across various environments such as outdoor, indoor, and within vegetation. Our investigation underscores the prevalence of logarithmic decay in most empirical models. In addition, we survey the relationship between model parameters and environmental factors, clearing their nuanced interplay. Analyzing published measurement results, we extract the log-distance model parameters to decipher environmental influences comprehensively. Drawing insights from published measurement results for LoRa, we compare them with the model's outcomes, highlighting successes and limitations. We additionally explore the application of multi-slope models to LoRa measurements to evaluate its effectiveness in enhancing the accuracy of path loss prediction. Finally, we propose new lines for future research in propagation modelling to improve empirical models.

Non-Contact Vision-Based Techniques of Vital Sign Monitoring: Systematic Review.

The development of non-contact techniques for monitoring human vital signs has significant potential to improve patient care in diverse settings. By facilitating easier and more convenient monitoring, these techniques can prevent serious health issues and improve patient outcomes, especially for those unable or unwilling to travel to traditional healthcare environments. This systematic review examines recent advancements in non-contact vital sign monitoring techniques, evaluating publicly available datasets and signal preprocessing methods. Additionally, we identified potential future research directions in this rapidly evolving field.