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This study aimed to develop and evaluate a costeffective Inertial Measurement Unit (IMU) system for gait analysis, comparing its performance with the Vicon system and the VideoPose3D algorithm. The system comprises five calibrated sensors and a mobile app to measure lower body orientation during gait and stair climbing. Eight healthy participants were involved in the experiment, each performing ten repetitions to analyze hip and knee flexion angles. The IMU system demonstrated significantly lower mean square error than deep learning-based approaches and comparable results to the Vicon system, indicating its potential for clinical and research applications.

Wound healing can be delayed if the biomechanical stability of the wound closure is inadequate. Therefore, it is necessary to investigate different suturing techniques for their biomechanical stability. In this study, suturing techniques suitable for the forehead area were investigated. For this application, a special test setup was developed to simulate the curvature of the forehead and the corresponding physiological configuration. The average forehead curvature is 62.24 ± 4.11 mm in radius. To simulate this curvature, the skin specimens are subjected to tensile stress over the spherical surface using a standard uniaxial testing machine. For the evaluation, an automated evaluation tool for MATLAB was also developed. Three different suturing techniques (Straight, Lazy-S, Zigzag) were investigated and tested for their biomechanical stability. Of the three suturing techniques, the Zigzag suture proved to be the most stable with the highest stiffness of 44.23 ± 8.18 % and the highest final failure of 32.60 ± 4.95 % (relative to the control sample without incision). The study has shown that the test setup can be used to investigate different forehead suture techniques.

Ewing sarcomas are malignant neoplasm entities typically found in children and adolescents. Early detection is crucial for therapy and prognosis. Due to the low incidence the general experience as well as according data is limited. Novel support tools for diagnosis, such as deep learning models for image interpretation, are required. While acquiring sufficient data is a common obstacle in medicine, several techniques to tackle small data sets have emerged. The general necessity of large data sets in addition to a rare disease lead to the question whether transfer learning can solve the issue of limited data and subsequently support tasks such as distinguishing Ewing sarcoma from its main differential diagnosis (acute osteomyelitis) in paediatric radiographs. 42,608 unstructured radiographs from our musculoskeletal tumour centre were retrieved from the PACS. The images were clustered with a DeepCluster, a self-supervised algorithm. 1000 clusters were used for the upstream task (pretraining). Following, the pretrained classification network was applied for the downstream task of differentiating Ewing sarcoma and acute osteomyelitis. An untrained network achieved an accuracy of 81.5%/54.2%, while an ImageNet-pretrained network resulted in 89.6%/70.8% for validation and testing, respectively. Our transfer learning approach surpassed the best result by 4.4%/17.3% percentage points. Transfer learning demonstrated to be a powerful technique to support image interpretation tasks. Even for small data sets, the impact can be significant. However, transfer learning is not a final solution to small data sets. To achieve clinically relevant results, a structured and systematic data acquisition is of paramount importance.

Introduction: Osteosynthesis of the equine femur is still a challenge for veterinary medicine. Even though intramedullary fracture fixation is possible nowadays, the varying geometry of the medullary cavity along the bone axis is a critical factor. Limited contact area between implant and bone can cause insufficient primary stability. In this study, it was investigated whether the osteosynthesis stability can be improved with a form-adaptive reinforcement for the diaphyseal part of the proximal fragment. Material and Methods: Eight equine femora were fitted with intramedullary nail osteosynthesis and analyzed by 4-point bending. Virtual position planning of the ex-vivo implantation using CT-data increased comparability. For five femora the proximal fragment was reinforced with a flexible polymer mixture. Longterm stability was tested via cyclic loading. Bending stiffness and its development due to cyclic loading was evaluated before and after reinforcement procedure. Finally, load-to-failure was tested in the same setup. Results and Discussion: The application of the polymer reinforcement increased the maximum torque in the load-tofailure measurement by 26%. Bending stiffness was not affected in the measured loading range by the reinforcement. Cyclic loading increased bending stiffness for a conditioned state but showed to be reversible for the most part. Conclusion: The fracture adjacent reinforcement showed to be beneficial to the osteosynthesis stability, but further investigation is necessary for surgical application.

For the development of new types of hip implants for acetabulum revision, it is beneficial to analyse the acetabular defects of the indication group in advance. In order to be able to specially compare the bone defects with each other, a normalisation and accompanying scaling of the pelvis is necessary. Uniform scaling is required so that the bone structures are not distorted. In the following study, three scaling methods based on the minimal bounding box and sphere principle are compared with a method using 14 landmarks on the pelvis.The landmark method is applied to determine the true scaling factor. For the comparison of the different methods, 40 female pelvic models with an acetabular defect are analysed. In the comparison of the scaling methods, the method using minimal bounding spheres shows the least deviation from the landmark method (mean difference 3.30 ± 2.17 %). Due to the fact that no preprocessing (definition of the landmarks) is required and the fast implementation of the algorithm, the minimal bounding sphere is to be preferred to the landmark method for a fast size estimation.

UKM Kartifarm Jaya Abadi dengan produk kopi bubuk merk Liber.Co dalam proses pengembangan usahanya mengalami beberapa kendala terkait standar mutu, kemasan, perizinan, sertifikasi produk, serta pasokan produk yang akan dijual. Kualitas adalah aspek terpenting dari pemasaran kopi, salah satunya adalah kualitas fisik dan visual kopi. Pada penelitian ini dilakukan karakterisasi mutu fisik kopi bubuk Liber.Co untuk mengetahui kesesuaiannya dengan SNI 01-3542-2004 Syarat Mutu Kopi Bubuk. Hasil menunjukkan kopi bubuk liberika Sambas yang diproduksi CV. KartiFarm Jaya Abadi dengan merk Liber.Co memiliki karakteristik mutu fisik kopi bubuk yang sesuai dengan persyaratan SNI 01-3542-2004: Kopi Bubuk. Mutu fisik berupa keadaan bau atau aroma, warna, dan rasa kopi bubuk liberika Sambas menunjukkan keadaan normal.

Objectives: The aim of the study is to determine if law enforcement officers develop subclinical atherosclerotic cardiovascular disease (ASCVD) earlier than nonofficers and, if so, the extent to which conventional risk factors explain this difference. Methods: Estimated pulse wave velocity (ePWV) was the marker of subclinical ASCVD. EPWV, ASCVD risk factors, metabolic syndrome (MetS), and 10-year risk for ASCVD were compared among 408 law enforcement officers and a civilian cohort. Results: EPWV, 10-year ASCVD risk, and MetS prevalence increased significantly with age. All but the officers age 55 and older had higher ePWV cohort than the civilian cohort ( P < 0.001). Ten-year ASCVD risk explained the most variability of ePWV ( R2 = 0.49, P < 0.001). Conclusions: Officers develop subclinical ASCVD earlier than nonofficers. Conventional ASCVD risk factors only explain about half of this increase. Occupational factors may play a role in contributing to this increased ASCVD risk., Competing Interests: Conflict of interest: None declared., (Copyright © 2024 American College of Occupational and Environmental Medicine.)

Ultrafast science builds on dynamic compositions of precisely timed light pulses, and evolving groups of pulses are observed in almost every mode-locked laser. However, the underlying physics has rarely been controlled or used until now. Here, we demonstrate a general approach to control soliton motion inside a dual-comb laser and the programmable synthesis of ultrashort pulse patterns. Introducing single-pulse modulation inside an Er:fiber laser, we rapidly shift the timing between two temporally separated soliton combs. Their superposition outside the cavity yields ultrashort soliton sequences. On the basis of real-time spectral interferometry, we observe the deterministic switching of intersoliton separation arising from the interplay of attracting and repulsing forces via ultrafast nonlinearity and laser gain dynamics. Harnessing these insights, we demonstrate the high-speed all-optical synthesis of nano- to picosecond pump-probe delays and programmable free-form soliton trajectories. This concept may pave the way to a new class of all-optical delay generators for ultrafast measurements at unprecedented high tuning, cycling, and acquisition speeds.

Differential activation of the renin-angiotensin system (RAS) likely contributes to sex differences in cardiovascular outcomes in premenopausal women compared with age-matched men. Women demonstrate reduced activation of the vasoconstrictor angiotensin II type 1 receptors (AT 1 R) compared with men, and evidence suggests that women also likely have increased sensitivity of the vasodilatory angiotensin II type 2 receptors (AT 2 R). However, few in vivo studies have directly examined sex differences in AT 2 R-mediated dilation, or the balance between AT 1 R- and AT 2 R-mediated vascular responses in humans. Using the cutaneous microcirculation as a model, we hypothesized that AT 2 R-mediated dilation would be greater in premenopausal women compared with men, and that AT 1 R-blockade would augment AT 2 R-mediated dilation to a greater extent in men than in women. Twelve healthy women (22 ± 3 yr) and 12 men (23 ± 5 yr) had two intradermal microdialysis fibers placed in the ventral forearm for graded infusions of compound 21 (AT 2 R agonist; 10 -12 to 10 -8 M) in a control fiber site and a site treated with 43 µM losartan (AT 1 R antagonist). Red blood cell flux was measured continuously by laser-Doppler flowmetry, and cutaneous vascular conductance [CVC = flux/mean arterial pressure (MAP)] was normalized to maximum [%max; 28 mM sodium nitroprusside (SNP) + 43 °C]. Women had greater AT 2 R-mediated dilation compared with men (women: 25 ± 4 vs. men: 15 ± 2%max, P = 0.03). Local AT 1 R inhibition increased AT 2 R-mediated dilation in men (losartan: 26 ± 4 vs. control: 15 ± 2%max, P < 0.001) but had no effect in women (losartan: 27 ± 6 vs. control: 25 ± 4%max, P > 0.05). These data suggest that premenopausal women have a greater AT 2 R-mediated vasodilation response than men, and that AT 1 R activation inhibits AT 2 R-mediated dilation in men, but not in women. NEW & NOTEWORTHY Premenopausal women have greater protection against cardiovascular disease than age-matched men. However, the role of vasoconstrictor angiotensin II type 1 receptors (AT 1 R) and vasodilatory angiotensin II type 2 receptors (AT 2 R) in mediating these sex differences is unclear. Here, we demonstrate that women have greater AT 2 R-mediated vasodilation than men and that AT 1 R negates AT 2 R-mediated dilation in men, but not in women.

Background: Veterans suffer substantial morbidity and mortality from lung cancer. Lung cancer screening (LCS) with low-dose computed tomography (LDCT) can reduce mortality. Guidelines recommend counseling and shared decision-making (SDM) to address the benefits and harms of screening and the importance of tobacco cessation before patients undergo screening., Observations: We implemented a centralized LCS program at the Iowa City Veterans Affairs Medical Center with a nurse program coordinator (NPC)-led telephone visit. Our multidisciplinary team ensured that veterans referred from primary care met eligibility criteria, that LDCT results were correctly coded by radiology, and that pulmonary promptly evaluated abnormal LDCT. The NPC mailed a decision aid to the veteran and scheduled a SDM telephone visit. We surveyed veterans after the visit using validated measures to assess knowledge, decisional conflict, and quality of decision making. We conducted 105 SDM visits, and 91 veterans agreed to LDCT. Overall, 84% of veterans reported no decisional conflict, and 59% reported high-quality decision making. While most veterans correctly answered questions about the harms of radiation, false-positive results, and overdiagnosis, few knew when to stop screening, and most overestimated the benefit of screening and the predictive value of an abnormal scan. Tobacco cessation interventions were offered to 72 currently smoking veterans., Conclusions: We successfully implemented an LCS program that provides SDM and tobacco cessation support using a centralized telehealth model. While veterans were confident about screening decisions, knowledge testing indicated important deficits, and many did not engage meaningfully in SDM. Clinicians should frame the decision as patient centered at the time of referral, highlight the importance of SDM, and be able to provide adequate decision support., Competing Interests: Author disclosures The study was supported by a grant from the Office of Rural Health (ORH) (NOMAD #03526) awarded to Richard Hoffman. The funding body did not play a role in the design of the study or the collection and analysis of data. Lisa Lowenstein and Robert Volk are supported by a grant funded by the National Institutes of Health, National Cancer Institute, USA, under award number P30CA016672, using the Shared Decision-Making Core, and by a grant from the Cancer Prevention and Research Institute of Texas (RP160674). None of the other authors have any disclosures. None of the authors have conflicts of interest with the work., (Copyright © 2023 Frontline Medical Communications Inc., Parsippany, NJ, USA.)

Introduction: Sleep apnea (SA) is highly prevalent in patients with chronic kidney disease and may contribute to the development and/or progression of this condition. Previous studies suggest that dysregulation of renal hemodynamics and oxygen flux may play a key role in this process. The present study sought to determine how chronic intermittent hypoxia (CIH) associated with SA affects regulation of renal artery blood flow (RBF), renal microcirculatory perfusion (RP), glomerular filtration rate (GFR), and cortical and medullary tissue PO 2 as well as expression of genes that could contribute to renal injury. We hypothesized that normoxic RBF and tissue PO 2 would be reduced after CIH, but that GFR would be increased relative to baseline, and that RBF, RP, and tissue PO 2 would be decreased to a greater extent in CIH vs. sham during exposure to intermittent asphyxia (IA, F i O 2 0.10/F i CO 2 0.03). Additionally, we hypothesized that gene programs promoting oxidative stress and fibrosis would be activated by CIH in renal tissue. Methods: All physiological variables were measured at baseline (F i O 2 0.21) and during exposure to 10 episodes of IA (excluding GFR). Results: GFR was higher in CIH-conditioned vs. sham ( p < 0.05), whereas normoxic RBF and renal tissue PO 2 were significantly lower in CIH vs. sham ( p < 0.05). Reductions in RBF, RP, and renal tissue PO 2 during IA occurred in both groups but to a greater extent in CIH ( p < 0.05). Pro-oxidative and pro-fibrotic gene programs were activated in renal tissue from CIH but not sham. Conclusion: CIH adversely affects renal hemodynamic regulation and oxygen flux during both normoxia and IA and results in changes in renal tissue gene expression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kious, Savage, Twohey, Highum, Philipose, Díaz, Del Rio, Lang, Clayton and Marcus.)

Background: 18F-flortaucipir PET received FDA approval to visualize aggregated neurofibrillary tangles (NFTs) in brains of adult patients with cognitive impairment being evaluated for Alzheimer's disease (AD). However, manufacturer's guidelines for visual interpretation of 18F-flortaucipir PET differ from how 18F-flortaucipir PET has been measured in research settings using standardized uptake value ratios (SUVRs). How visual interpretation relates to 18F-flortaucipir PET SUVR, cerebrospinal fluid (CSF) biomarkers, or longitudinal clinical assessment is not well understood., Objective: We compare various diagnostic methods in participants enrolled in longitudinal observational studies of aging and memory (n = 189, 23 were cognitively impaired)., Methods: Participants had tau PET, Aβ PET, MRI, and clinical and cognitive evaluation within 18 months (n = 189); the majority (n = 144) also underwent lumbar puncture. Two radiologists followed manufacturer's guidelines for 18F-flortaucipir PET visual interpretation., Results: Visual interpretation had high agreement with SUVR (98.4%)and moderate agreement with CSF p-tau181 (86.1%). Two participants demonstrated 18F-flortaucipir uptake from meningiomas. Visual interpretation could not predict follow-up clinical assessment in 9.52% of cases., Conclusion: Visual interpretation was highly consistent with SUVR (discordant participants had hemorrhagic infarcts or occipital-predominant AD NFT deposition) and moderately consistent with CSF p-tau181 (discordant participants had AD pathophysiology not detectable on tau PET). However, close association between AD NFT deposition and clinical onset in group-level studies does not necessarily hold at the individual level, with discrepancies arising from atypical AD, vascular dementia, or frontotemporal dementia. A better understanding of relationships across imaging, CSF biomarkers, and clinical assessment is needed to provide appropriate diagnoses for these individuals.

Objective: Reproducibility of the reflex cutaneous vasoconstriction response is currently unknown. Our aim was to determine the test-retest reproducibility of laser speckle contrast imaging (LSCI) and varying sampling depths of laser Doppler flowmetry (LDF) in response to whole-body cooling., Methods: Over two studies, nine and fourteen healthy, young adults underwent a 40-min cooling bout over two separate experiments. Participants were cooled from 34.0 °C to 30.5 °C and held at a 30.5 °C plateau for 10-min prior to rewarming. Throughout the cooling bout, changes in blood flow were measured as LSCI flux and LDF flux for Study 1 and LDF flux by three different LDF sampling depths in Study 2. Test-retest reproducibility and reliability were evaluated by the coefficient of variation (CV) and intraclass correlation coefficients (ICC), respectively. Vasoconstriction was presented as cutaneous vascular conductance (CVC = flux / mean arterial pressure) and expressed as a percent change from baseline (%ΔCVC BASELINE )., Results: For Study 1, test-retest reproducibility displayed good reproducibility for LSCI (CV: <9.0%) and good-to-moderate for LDF (CV: <17.0%) throughout the cooling bout and at plateau (LSCI CV: 1.0%; LDF CV: 1.9%). For Study 2, all Doppler depths displayed good reproducibility during the cooling bout (CV: <9.0%) and at plateau (CV: 0.9-2.0%). Only LSCI demonstrated reliability across both studies (ICC: 0.58-0.88). A reduced vasoconstriction response was measured with the shallowest penetration in the skin (LSCI: 26 ± 0.9%ΔCVC BASELINE ) compared to the Doppler with the deepest penetration (35 ± 0.6%ΔCVC BASELINE , p < 0.001)., Conclusions: Although Dopplers better discriminate the reflex cutaneous vasoconstriction response, LSCI exhibits greater test-retest reproducibility and reliability, and thus may be more suitable for longitudinal assessments., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Remote ischaemic preconditioning (RIPC), induced by intermittent periods of limb ischaemia and reperfusion, confers cardiac and vascular protection from subsequent ischaemia-reperfusion (IR) injury. Early animal studies reliably demonstrate that RIPC attenuated infarct size and preserved cardiac tissue. However, translating these adaptations to clinical practice in humans has been challenging. Large clinical studies have found inconsistent results with respect to RIPC eliciting IR injury protection or improving clinical outcomes. Follow-up studies have implicated several factors that potentially affect the efficacy of RIPC in humans such as age, fitness, frequency, disease state and interactions with medications. Thus, realizing the clinical potential for RIPC may require a human experimental model where confounding factors are more effectively controlled and underlying mechanisms can be further elucidated. In this review, we highlight recent experimental findings in the peripheral circulation that have added valuable insight on the mechanisms and clinical benefit of RIPC in humans. Central to this discussion is the critical role of timing (i.e. immediate vs. delayed effects following a single bout of RIPC) and the frequency of RIPC. Limited evidence in humans has demonstrated that repeated bouts of RIPC over several days uniquely improves vascular function beyond that observed with a single bout alone. Since changes in resistance vessel and microvascular function often precede symptoms and diagnosis of cardiovascular disease, repeated bouts of RIPC may be promising as a preclinical intervention to prevent or delay cardiovascular disease progression., (© 2022 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

The optimal frequency and duration of remote ischemic preconditioning (RIPC) that augments microvascular function is unknown. A single bout of RIPC increases cutaneous endothelial function for ∼48 h, whereas 1 week of daily RIPC bouts improves more sustained endothelium-independent function. We hypothesized that 3 days of RIPC separated by rest days (3QOD RIPC) would result in sustained increases in both endothelium-dependent and endothelium-independent functions. Cutaneous microvascular function was assessed in 13 healthy young participants (aged 20.5 ± 3.9 years; 5 males, 8 females) before 3QOD and then 24, 48, and 72 h and a week after 3QOD. RIPC consisted of four repetitions of 5 min of blood flow occlusion separated by 5 min of reperfusion. Skin blood flow responses to local heating ( T loc = 42°C), acetylcholine (Ach), and sodium nitroprusside (SNP) were measured using laser speckle contrast imaging and expressed as cutaneous vascular conductance (CVC = PU⋅mmHg -1 ). Local heating-mediated vasodilation was increased 72 h after 3QOD and the increased responsivity persisted a week later (1.08 ± 0.24 vs. 1.34 ± 0.46, 1.21 ± 0.36 PU⋅mmHg -1 ; ΔCVC, pre-RIPC vs. 72 h, a week after 3QOD; P = 0.054). Ach-induced cutaneous vasodilation increased a week after 3QOD (0.73 ± 0.41 vs. 0.95 ± 0.49 PU⋅mmHg -1 ; ΔCVC, pre-RIPC vs. a week after 3QOD; P < 0.05). SNP-induced cutaneous vasodilation increased 24 h after 3QOD (0.47 ± 0.28 vs. 0.63 ± 0.35 PU⋅mmHg -1 ; ΔCVC, pre-RIPC vs. 24 h; P < 0.05), but this change did not persist thereafter. Thus, 3QOD induced sustained improvement in endothelium-dependent vasodilation but was not sufficient to sustain increases in endothelium-independent vasodilation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kim, Franke and Lang.)

Rationale and Objectives: Pulmonary CTA is the current standard method to assess for suspected pulmonary embolism. In some instances, the test results in low confidence interpretations. Our purpose was to compare the diagnostic confidence for three different scan protocols., Materials and Methods: Pulmonary CTA images from 401 patients were retrospectively analyzed. 202 studies used a tube voltage of 120 kVp and a contrast injection rate of 4 cc/s, 99 studies 120 kVp and 5 cc/s, and 100 studies 100 kVp and 4 cc/s. The level of diagnostic confidence was extracted from the final clinical reports. For each study, attenuation of the pulmonary artery, image noise, signal-to-noise ratio (SNR), and radiation dose were compared., Results: The 120 kVp, 5 cc/s protocol resulted in high diagnostic confidence in 84% of cases, more than with the 120 kVp, 4cc/s (65%) and the 100 kVp protocol (65%, p < 0.004). The 100 kVp protocol had a lower radiation dose, higher image noise, lower SNR, but equal and higher attenuation values of the pulmonary artery., Conclusion: The reduction of tube voltage to 100 kVp at 4 cc/s maintains diagnostic confidence with lower radiation exposure, but does not equal the higher confidence achieved with 120 kVp at 5cc/s., (Copyright © 2021 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Microscopic electric fields govern the majority of elementary excitations in condensed matter and drive electronics at frequencies approaching the Terahertz (THz) regime. However, only few imaging schemes are able to resolve sub-wavelength fields in the THz range, such as scanning-probe techniques, electro-optic sampling, and ultrafast electron microscopy. Still, intrinsic constraints on sample geometry, acquisition speed and field strength limit their applicability. Here, we harness the quantum-confined Stark-effect to encode ultrafast electric near-fields into colloidal quantum dot luminescence. Our approach, termed Quantum-probe Field Microscopy (QFIM), combines far-field imaging of visible photons with phase-resolved sampling of electric waveforms. By capturing ultrafast movies, we spatio-temporally resolve a Terahertz resonance inside a bowtie antenna and unveil the propagation of a Terahertz waveguide excitation deeply in the sub-wavelength regime. The demonstrated QFIM approach is compatible with strong-field excitation and sub-micrometer resolution-introducing a direct route towards ultrafast field imaging of complex nanodevices in-operando., (© 2022. The Author(s).)