Effect of rapid cooling, frozen storage, and thawing on the passive viscoelastic properties and structure of the rat aorta.

Biological tissues decay over time after harvesting, which alters their biomechanical properties. This poses logistical challenges for studies investigating passive arterial biomechanics as tissues need to be characterized shortly after excision. Freezing and cryopreservation methods can help alleviate the need for biomechanical testing of fresh tissue in human ex vivo studies. However, these methods tend to eliminate or reduce arterial cell functionality and affect passive biomechanics. Furthermore, their impact on dynamic arterial biomechanics remains unknown despite arterial viscoelastic properties being an integral component contributing to arterial stiffness under in vivo loading conditions. The present study aims to investigate the impact of rapid cooling and subsequent storage at -80 °C on the passive viscoelastic properties of arterial tissue and aid in ascertaining whether this is a suitable method to delay tissue analysis for studies investigating passive arterial biomechanics. Control and frozen abdominal rat aorta segments were quasi-statically and dynamically tested using a biaxial testing set-up. The results were modeled using a constituent-based quasi-linear viscoelastic modeling framework, yielding directional stiffness parameters, individual constituent biomechanical contributions, and a quantification of viscoelastic stiffening under dynamic pressurization conditions. Frozen samples displayed significantly decreased wall thickness, viscoelastic dissipation, viscoelastic stiffening, and significantly decreased circumferential deformation with changes in luminal pressure. Furthermore, frozen samples displayed significantly increased circumferential stiffness, pulse wave velocity, and collagen load bearing. Consequently, these changes should be considered when utilizing this tissue preservation method to delay biomechanical characterization of rat aortic tissue.

Effectiveness of strategies to suppress antibodies to infliximab in pediatric inflammatory bowel disease.

OBJECTIVES: Antibodies to infliximab (ATIs) are associated with loss of response in children with inflammatory bowel disease (IBD). We aimed to describe the effectiveness of strategies for treatment modification following ATI development in pediatric IBD: (1) treatment escalation; and (2) switching to another anti-TNF agent. METHODS: This multicenter retrospective study included children with IBD (4-18 years) on infliximab. Therapeutic drug monitoring (TDM) < 6 months and corticosteroid-free remission following each strategy were evaluated for low ATI titers (≤30 AU/mL) and high ATI titers (>30 AU/mL). RESULTS: Anti-infliximab antibodies were detected in 52/288 patients (18%) after a median of 15.3 months. Three of 52 ATI-positive patients were excluded due to alternative treatments. Of the remaining 49 patients, 19 had low titers and 30 had high titers. Of 19 low-ATIs, 16 (84%) underwent treatment escalation with infliximab (IFX). Of 13 patients with TDM available, seven (54%) achieved ATI suppression at subsequent TDM and 12 (92%) at any time point. Among 30 patients with high-ATIs, 17 (57%) continued with IFX; immunomodulators were started in seven patients. Of 14 patients with TDM, seven (50%) achieved ATI suppression at subsequent TDM and 10 (71%) at any time point. At 24 months of follow-up, 73% of low-ATI patients and 50% of high-ATI patients could continue with IFX without steroids. Thirteen of 30 high-ATI patients (43%) switched to another anti-TNF agent, of whom 54% and 46% had clinical response at 6 and 24 months, respectively. CONCLUSIONS: Dose optimization and/or adding an immunomodulator seem effective in suppressing low ATI titers. This strategy could also be considered in high ATI titers before switching.

Urinary Marker Profiles in Heart Failure with Reduced Versus Preserved Ejection Fraction.

BACKGROUND: Recent data suggest different causes of renal dysfunction between heart failure with reduced (HFrEF) versus preserved ejection fraction (HFpEF). We therefore studied a wide range of urinary markers reflecting different nephron segments in heart failure patients. METHODS: In 2070, in chronic heart failure patients, we measured several established and upcoming urinary markers reflecting different nephron segments. RESULTS: Mean age was 70 ± 12 years, 74% was male and 81% (n = 1677) had HFrEF. Mean estimated glomerular filtration rate (eGFR) was lower in patients with HFpEF (56 ± 23 versus 63 ± 23 ml/min/1.73 m2, P = 0.001). Patients with HFpEF had significantly higher values of NGAL (58.1 [24.0-124.8] versus 28.1 [14.6-66.9] µg/gCr, P < 0.001) and KIM-1 (2.28 [1.49-4.37] versus 1.79 [0.85-3.49] µg/gCr, P = 0.001). These differences were more pronounced in patients with an eGFR > 60 ml/min/1.73m2. CONCLUSIONS: HFpEF patients showed more evidence of tubular damage and/or dysfunction compared with HFrEF patients, in particular when glomerular function was preserved.

Using PROM(I)S to measure health-related quality of life in patients with a bone fracture: An observational cohort study.

INTRODUCTION: The incidence of patients with fractures is increasing and so is the impact on health care systems and society. To improve patient care, measurement of disabilities and impaired health experiences after traumatic musculoskeletal injuries are important. Next to objective clinical parameters, PROM(I)S can be used to map health domains important to patients. We aimed to objectify different aspects of (health-related) quality of life in fracture patients, including the ability to participate in social roles and activities using PROMIS among other PROMs. METHODS: An observational cohort study was performed in which health-related quality of life in fracture patients was measured. Patients aged 18 year and older either treated conservatively or surgically between November 2020 and June 2022 were included. Participants were followed for a maximum of one year and completed the following PROMs: PROMIS-CAT physical function, PROMIS-CAT pain interference, PROMIS-CAT ability to participate in social roles and activities and LEFS or QDASH. We applied a univariate linear mixed model to evaluate significance of improvement. RESULTS: Seven hundred-forty six patients with a mean age of 54.4 years were included. Mean PROMIS scores were structurally inferior in the lower extremity (LE) fracture group in comparison with the upper extremity (UE) fracture group. For "PROMIS physical function", UE fracture patients performed better and showed physical progression earlier. For "PROMIS pain interference", UE fracture patients experienced fewer limitations, but it took longer to experience improvement in this group. For "PROMIS ability to participate in social roles", significant improvement was only seen in the UE fracture group at one year follow up. CONCLUSION: Upper -and lower extremity fractures can have a significant impact on physical function and social health. Patients with UE fractures tend to have fewer limitations compared to LE fracture patients. Physical function and pain interference is most impaired shortly after the injury in all fracture patients and show significant changes over time, social health improves less over time. Moment of measurement should be based on type of fracture and can differ between individual patients, but when generic measures and outcomes are desirable, PROMIS questionnaires can potentially be used measurement.

Recovery to normal vital functions and acid-base status after a severe trauma in Level I versus Level II Trauma Centres.

PURPOSE: In the Netherlands, approximately 70% of severely injured patients (ISS ≥ 16) are transported directly to a Level I trauma center. This study compared the time needed to return to normal vital parameters and normal acid-base status in severely injured patients and some in-hospital processes in Level I versus Level II trauma centers. METHODS: This retrospective cohort study included all adult severely injured patients or adult trauma patients admitted to the intensive care unit between 2015 and 2020 in a Dutch trauma region. The primary endpoint was time until normal vital parameters and acid-base status. Secondary endpoints were complication rate, hospital length of stay, emergency department length of stay, and time until a computed tomography (CT) scan. RESULTS: A total of 2345 patients were included. Patients admitted to a Level I trauma center had a significantly higher rate of normalization of vital parameters over time (HR 1.51). There was no significant difference in normalization rate of the acid-base status over time (HR 1.10). In Level I trauma centers, time spent at the emergency department and time until the CT scan was significantly shorter (respectively, ß - 38 min and ß - 77 min), and the complication rate was significantly lower (OR 0.35). CONCLUSION: Severely injured patients admitted to a Level I trauma center require less time to normalize their vital functions. Level I centers are better equipped, resulting in better in-hospital processes with shorter time at the emergency department and shorter time until a CT scan.

Correlated x-ray fluorescence and ptychographic nano-tomography on Rembrandt's The Night Watch reveals unknown lead "layer".

The Night Watch, one of the most famous masterpieces by Rembrandt, is the subject of a large research and conservation project. For the conservation treatment, it is of great importance to understand its current condition. Correlated nano-tomography using x-ray fluorescence and ptychography revealed a-so far unknown-lead-containing "layer", which likely acts as a protective impregnation layer applied on the canvas before the quartz-clay ground was applied. This layer might explain the presence of lead soap protrusions in areas where no other lead components are present. In addition to the three-dimensional elemental mapping, ptychography visualizes and quantifies components not detectable by hard x-ray fluorescence such as the organic fraction and quartz. The first-time use of this combination of synchrotron-based techniques on a historic paint micro-sample shows it to be an important tool to better interpret the results of noninvasive imaging techniques operating on the macroscale.

Nonoperative treatment of multiple rib fractures, the results to beat: International multicenter prospective cohort study among 845 patients.

BACKGROUND: Optimal treatment (i.e. nonoperative or operative) for patients with multiple rib fractures remains debated. Studies that compare treatments are rationalized by the alleged poor outcomes of nonoperative treatment. METHODS: The aim of this prospective international multicenter cohort study (between January 2018 and March 2021) with one-year follow-up, was to report contemporary outcomes of nonoperatively treated patients with multiple rib fractures. Including 845 patients with three or more rib fractures. Primary outcome was in-hospital mortality. Secondary outcomes included hospital length of stay (HLOS), (pulmonary) complications, and quality of life. RESULTS: Mean age was 57.7 ± 17.0 years, median Injury Severity Score was 17 (13-22) and the median number of rib fractures was 6 (4-8). In-hospital mortality rate was 1.5% (n = 13), 112 (13.3%) patients had pneumonia and four (0.5%) patients developed a symptomatic non-union. The median HLOS was 7 (4-13) days, and median intensive care unit length of stay was 2 (1-5) days. Mean EQ-5D-5L index value was 0.83 ± 0.18 one year after trauma. Polytrauma patients had a median HLOS of 10 (6-18) days, a pneumonia rate of 17.6% (n = 77) and mortality rate of 1.7% (n = 7). Elderly patients (≥65 years) had a median HLOS of 9 (5-15) days, a pneumonia rate of 19.7% (n = 57) and mortality rate of 4.1% (n = 12). CONCLUSIONS: Overall, nonoperative treatment of patients with multiple rib fractures shows low mortality and morbidity rate and good quality of life after one year. Future studies evaluating the benefit of operative stabilisation should use contemporary outcomes to establish the therapeutic margin of rib fixation. LEVEL OF EVIDENCE: Level III, Therapeutic/Care Management.

Trajectories of renal biomarkers and new-onset heart failure in the general population: Findings from the PREVEND study.

AIMS: Renal dysfunction is one of the most critical risk factors for developing heart failure (HF). However, the association between repeated measures of renal function and incident HF remains unclear. Therefore, this study investigated the longitudinal trajectories of urinary albumin excretion (UAE) and serum creatinine and their association with new-onset HF and all-cause mortality. METHODS AND RESULTS: Using group-based trajectory analysis, we estimated trajectories of UAE and serum creatinine in 6881 participants from the Prevention of Renal and Vascular End-stage Disease (PREVEND) study and their association with new-onset HF and all-cause death during the 11-years of follow-up. Most participants had stable low UAE or serum creatinine. Participants with persistently higher UAE or serum creatinine were older, more often men, and more often had comorbidities, such as diabetes, a previous myocardial infarction or dyslipidaemia. Participants with persistently high UAE had a higher risk of new-onset HF or all-cause mortality, whereas stable serum creatinine trajectories showed a linear association for new-onset HF and no association with all-cause mortality. CONCLUSION: Our population-based study identified different but often stable longitudinal patterns of UAE and serum creatinine. Patients with persistently worse renal function, such as higher UAE or serum creatinine, were at a higher risk of HF or mortality.

Constituent-based quasi-linear viscoelasticity: a revised quasi-linear modelling framework to capture nonlinear viscoelasticity in arteries.

Arteries exhibit fully nonlinear viscoelastic behaviours (i.e. both elastically and viscously nonlinear). While elastically nonlinear arterial models are well established, effective mathematical descriptions of nonlinear viscoelasticity are lacking. Quasi-linear viscoelasticity (QLV) offers a convenient way to mathematically describe viscoelasticity, but its viscous linearity assumption is unsuitable for whole-wall vascular applications. Conversely, application of fully nonlinear viscoelastic models, involving deformation-dependent viscous parameters, to experimental data is impractical and often reduces to identifying specific solutions for each tested loading condition. The present study aims to address this limitation: By applying QLV theory at the wall constituent rather than at the whole-wall level, the deformation-dependent relative contribution of the constituents allows to capture nonlinear viscoelasticity with a unique set of deformation-independent model parameters. Five murine common carotid arteries were subjected to a protocol of quasi-static and harmonic, pseudo-physiological biaxial loading conditions to characterise their viscoelastic behaviour. The arterial wall was modelled as a constrained mixture of an isotropic elastin matrix and four families of collagen fibres. Constituent-based QLV was implemented by assigning different relaxation functions to collagen- and elastin-borne parts of the wall stress. Nonlinearity in viscoelasticity was assessed via the pressure dependency of the dynamic-to-quasi-static stiffness ratio. The experimentally measured ratio increased with pressure, from 1.03 [Formula: see text] 0.03 (mean [Formula: see text] standard deviation) at 80-40 mmHg to 1.58 [Formula: see text] 0.22 at 160-120 mmHg. Constituent-based QLV captured well this trend by attributing the wall viscosity predominantly to collagen fibres, whose recruitment starts at physiological pressures. In conclusion, constituent-based QLV offers a practical and effective solution to model arterial viscoelasticity.

Sunlight Powered Continuous Flow Reverse Water Gas Shift Process Using a Plasmonic Au/TiO2 Nanocatalyst.

The continuous flow reverse water gas shift (rWGS) process was efficiently catalyzed by a plasmonic Au/TiO2 nanocatalyst using sunlight as sole and sustainable energy source. The influence of the catalyst bed thickness on the CO production rate was studied, and three different catalytic regimes were identified as direct plasmon catalysis (DPC), shielded plasmon catalysis (SPC) and unused plasmon catalysis (UPC). The CO2 : H2 ratio was optimized to 4 : 1 and a maximum CO production rate of 7420 mmol ⋅ m-2 ⋅ h-1 was achieved under mild reaction conditions (p=3.5 bar, no external heating, Ee =14.0 kW ⋅ m-2 ), corresponding to an aparent quantum efficiency of 4.15%. The stability of the Au/TiO2 catalyst was studied for 110 h continuous operation, maintaining more than 82% of the initial CO production rate. On/off experiments mimicking discontinuous sunlight powered processing furthermore showed that the Au/TiO2 catalyst was stable for 8 consecutive runs.

Seismic and medical ultrasound imaging of velocity and density variations by nonlinear vectorial inverse scattering.

We present an iterative nonlinear inverse scattering algorithm for high-resolution acoustic imaging of density and velocity variations. To solve the multi-parameter nonlinear direct scattering problem, the acoustic wave equation for inhomogeneous media in the frequency domain is transformed into a vectorial integral equation of the Lippmann-Schwinger type for the combined pressure and pressure-gradient field. To solve the multi-parameter nonlinear inverse scattering problem, we use the Newton-Kantorovich method in conjunction with matrix-free representations of the Fréchet derivative operators and their adjoints. The approximate Hessian information that is accounted for in our iterative solution of the (nonlinear) multi-parameter inverse scattering problem is essential for the mitigation of multi-parameter cross talk effects. Numerical examples related to seismic and medical ultrasound breast imaging illustrate the performance of the new algorithm for multi-parameter acoustic imaging.

In patients with combined clavicle and multiple rib fractures, does fracture fixation of the clavicle improve clinical outcomes? A multicenter prospective cohort study of 232 patients.

BACKGROUND: Clavicle and rib fractures are often sustained concomitantly. The combination of injuries may result in decreased stability of the chest wall, making these patients prone to (respiratory) complications and prolonged hospitalization. This study aimed to assess whether adding chest wall stability by performing clavicle fixation improves clinical outcomes in patients with concurrent clavicle and rib fractures. METHODS: A prospective multicenter study was performed including all adult patients admitted between January 2018 and March 2021 with concurrent ipsilateral clavicle and rib fractures. Patients treated operatively versus nonoperatively for their clavicle fracture were matched using propensity score matching. The primary outcome was hospital length of stay (HLOS). Secondary outcomes were intensive care unit length of stay, duration of mechanical ventilation, pain, complications, and quality of life at 6 weeks and 12 months of follow-up. RESULTS: In total, 232 patients with concomitant ipsilateral clavicle and rib fractures were included. Fifty-two patients (22%) underwent operative treatment of which 39 could be adequately matched to 39 nonoperatively treated patients. No association was observed between clavicle plate fixation and HLOS (mean difference, 2.3 days; 95% confidence interval, -2.1 to 6.8; p = 0.301) or any secondary endpoint. Eight of the 180 nonoperatively treated patients (4%) had a symptomatic nonunion, for which 5 underwent secondary clavicle fixation. CONCLUSION: We found no evidence that, in patients with combined clavicle and multiple rib fractures, plate fixation of the clavicle reduces HLOS, pain, or (pulmonary) complications, nor that it improves quality of life. STUDY TYPE: Therapeutic/Care Management; Level III.

Implementing 3D fluoroscopy in the management of tibial plateau fractures: Shorter hospitalization and decline in revision surgery, but increase in the duration of surgery and radiation exposure.

BACKGROUND: Intraoperative 3D fluoroscopy (3DRX) is increasingly used in fracture management instead of conventional fluoroscopy (RX), but its effect on the treatment and outcome of tibial plateau fractures (TFs) is not well known. This study aims to evaluate whether the use of 3DRX in the treatment of tibial plateau fractures reduces the number of revision surgeries. METHODS: This retrospective cohort study includes all patients who underwent surgical treatment for TF in a single center from 2014 to 2018. Patient-, fracture-, and treatment characteristics were compared between the 3DRX and RX subgroups. The primary endpoint was the number of patients requiring revision surgery. Secondary endpoints were surgery duration, hospital length of stay, radiation exposure, postoperative complications, and secondary total knee arthroplasty. RESULTS: Eighty-seven patients were included, of which 36 were treated with 3DRX. Three patients in the RX group required revision surgery, while no revision surgery was performed in the 3DRX group (p = 0.265). The use of 3DRX resulted in significantly more intraoperative adjustments (25% versus 6%; p = 0.024) and an increase in surgery duration (by average of 28 min, p = 0.001), without a significant increase in postoperative wound infections (12% versus 19%; p = 0.374) or fracture-related infections (2% versus 2.8%; p = 0.802). The 3DRX group had an average radiation exposure of 7,985 mGy versus 1,273 mGy in the RX group (p<0.001). The hospital length of stay was 1 day shorter in the 3DRX group (5 days versus 4 days; p = 0.058). CONCLUSIONS: Implementing 3DRX in treating TFs improves the assessment of fracture alignment and implant position perioperatively, resulting in more intraoperative corrections and no revision surgeries within 6 weeks postoperatively. However, using 3DRX significantly increases perioperative radiation exposure and surgery duration without a significant rise in postoperative infections and a shorter hospital length of stay.

Quality of life and clinical outcomes of operatively treated patients with flail chest injuries: A multicentre prospective cohort study.

Introduction: Most studies about rib fractures focus on mortality and morbidity. Literature is scarce on long term and quality of life (QoL) outcomes. Therefore, we report QoL and long-term outcomes after rib fixation in flail chest patients. Methods: A prospective cohort study of clinical flail chest patients admitted to six level 1 trauma centres in the Netherlands and Switzerland between January 2018 and March 2021. Outcomes included in-hospital outcomes and long-term outcomes, such as QoL measurements 12 months after hospitalization using the EuroQoL five dimensions (EQ-5D) questionnaire. Results: Sixty-one operatively treated flail chest patients were included. Median hospital length of stay was 15 days and intensive care length of stay was 8 days. Sixteen (26%) patients developed pneumonia and two (3%) died. One year after hospitalization the mean EQ5D score was 0.78. Complication rates were low and included hemothorax (6%) pleural effusion (5%) and two revisions of the implant (3%). Implant related irritation was commonly reported by patients (n = 15, 25%). Conclusions: Rib fixation for flail chest injuries can be considered a safe procedure and with low mortality rates. Future studies should focus on quality of life rather than solely short-term outcomes.Trial registration: Registered in the Netherlands Trial Register NTR6833 on 13/11/2017 and the Swiss Ethics Committees Registration Number 2019-00668.

Accuracy of Prehospital Triage of Adult Patients With Traumatic Injuries Following Implementation of a Trauma Triage Intervention.

Importance: Adequate prehospital triage is pivotal to enable optimal care in inclusive trauma systems and reduce avoidable mortality, lifelong disabilities, and costs. A model has been developed to improve the prehospital allocation of patients with traumatic injuries and was incorporated in an application (app) to be implemented in prehospital practice. Objective: To evaluate the association between the implementation of a trauma triage (TT) intervention with an app and prehospital mistriage among adult trauma patients. Design, Setting, and Participants: This population-based, prospective quality improvement study was conducted in 3 of the 11 Dutch trauma regions (27.3%), with full coverage of the corresponding emergency medical services (EMS) regions participating in this study. Participants included adult patients (age ≥16 years) with traumatic injuries who were transported by ambulance between February 1, 2015, and October 31, 2019, from the scene of injury to any emergency department in the participating trauma regions. Data were analyzed between July 2020 and June 2021. Exposures: Implementation of the TT app and the awareness of need for adequate triage created by its implementation (ie, the TT intervention). Main Outcomes and Measures: The primary outcome was prehospital mistriage, evaluated in terms of undertriage and overtriage. Undertriage was defined as the proportion of patients with an Injury Severity Score (ISS) of 16 or greater who were initially transported to a lower-level trauma center (designated to treat patients who are mildly and moderately injured) and overtriage as the proportion of patients with an ISS of less than 16 who were initially transported to a higher-level trauma center (designated to treat patients who are severely injured). Results: A total of 80 738 patients were included (40 427 [50.1%] before and 40 311 [49.9%] after implementation of the intervention), with a median (IQR) age of 63.2 (40.0-79.7) years and 40 132 (49.7%) male patients. Undertriage decreased from 370 of 1163 patients (31.8%) to 267 of 995 patients (26.8%), while overtriage rates did not increase (8202 of 39 264 patients [20.9%] vs 8039 of 39 316 patients [20.4%]). The implementation of the intervention was associated with a statistically significantly reduced risk for undertriage (crude risk ratio [RR], 0.95; 95% CI, 0.92 to 0.99, P = .01; adjusted RR, 0.85; 95% CI, 0.76-0.95; P = .004), but the risk for overtriage was unchanged (crude RR, 1.00; 95% CI, 0.99-1.00; P = .13; adjusted RR, 1.01; 95% CI, 0.98-1.03; P = .49). Conclusions and Relevance: In this quality improvement study, implementation of the TT intervention was associated with improvements in rates of undertriage. Further research is needed to assess whether these findings are generalizable to other trauma systems.

Comparing Patient-Reported Outcomes Measurement Information System Computer Adaptive Testing With Existing Measures After Operative Interventions for Extremity Fractures.

INTRODUCTION: Patient-Reported Outcomes Measurement Information System (PROMIS) enables the use of computer adaptive testing (CAT). The aim of this prospective cohort study was to compare the most commonly used disease-specific instruments with PROMIS CAT questionnaires in patients with trauma. METHODS: All patients with trauma (ages 18-75) who underwent an operative intervention for an extremity fracture between June 1, 2018, and June 30, 2019, were included. The disease-specific instruments were the Quick Disabilities of the Arm, Shoulder, and Hand for upper extremity fractures and the Lower Extremity Functional Scale (LEFS) for lower extremity fractures. Pearson's correlation (r) between the disease-specific instruments and the PROMIS CAT questionnaires (PROMIS Physical Function, PROMIS Pain Interference, and PROMIS Ability to Participate in Social Roles and Activities) was calculated at week 2, week 6, month 3, and month 6. Construct validity and responsiveness were calculated. RESULTS: A total of 151 patients with an upper extremity fracture and 109 patients with a lower extremity fracture were included. At month 3 and month 6, the correlation was strong between the LEFS and PROMIS Physical Function (r = 0.88 and r = 0.90, respectively), and at month 3, the correlation was strong between the LEFS and PROMIS Social Roles and Activities (r = 0.72). At week 6, month 3, and month 6, there was a strong correlation between the Quick Disabilities of the Arm, Shoulder, and Hand and PROMIS Physical Function (r = 0.74, r = 0.70, and r = 0.76, respectively). CONCLUSIONS: The PROMIS CAT measures are acceptably related to existing non-CAT instruments and may be a useful tool during follow-up after operative interventions for extremity fractures.

Simulation-to-real generalization for deep-learning-based refraction-corrected ultrasound tomography image reconstruction.

Objective. The image reconstruction of ultrasound computed tomography is computationally expensive with conventional iterative methods. The fully learned direct deep learning reconstruction is promising to speed up image reconstruction significantly. However, for direct reconstruction from measurement data, due to the lack of real labeled data, the neural network is usually trained on a simulation dataset and shows poor performance on real data because of the simulation-to-real gap.Approach. To improve the simulation-to-real generalization of neural networks, a series of strategies are developed including a Fourier-transform-integrated neural network, measurement-domain data augmentation methods, and a self-supervised-learning-based patch-wise preprocessing neural network. Our strategies are evaluated on both the simulation dataset and real measurement datasets from two different prototype machines.Main results. The experimental results show that our deep learning methods help to improve the neural networks' robustness against noise and the generalizability to real measurement data.Significance. Our methods prove that it is possible for neural networks to achieve superior performance to traditional iterative reconstruction algorithms in imaging quality and allow for real-time 2D-image reconstruction. This study helps pave the path for the application of deep learning methods to practical ultrasound tomography image reconstruction based on simulation datasets.

Non-operative vs. operative treatment for multiple rib fractures after blunt thoracic trauma: a multicenter prospective cohort study.

BACKGROUND: Patients with multiple rib fractures without a clinical flail chest are increasingly being treated with rib fixation; however, high-quality evidence to support this development is lacking. METHODS: We conducted a prospective multicenter observational study comparing rib fixation to non-operative treatment in all patients aged 18 years and older with computed tomography confirmed multiple rib fractures without a clinical flail chest. Three centers performed rib fixation as standard of care. For adequate comparison, the other three centers performed only non-operative treatment. As such clinical equipoise formed the basis for the comparison in this study. Patients were matched using propensity score matching. RESULTS: In total 927 patients with multiple rib fractures were included. In the three hospitals that performed rib fixation, 80 (14%) out of 591 patients underwent rib fixation. From the nonoperative centers, on average 71 patients were adequately matched to 71 rib fixation patients after propensity score matching. Rib fixation was associated with an increase in hospital length of stay (HLOS) of 4.9 days (95%CI 0.8-9.1, p = 0.02) and a decrease in quality of life (QoL) measured by the EQ5D questionnaire at 1 year of 0.1 (95% CI - 0.2-0.0, p = 0.035) compared to non-operative treatment. A subgroup analysis of patients who received operative care within 72 h showed a similar decrease in QoL. Up to 22 patients (28%) who underwent surgery experienced implant-related irritation. CONCLUSIONS: We found no benefits and only detrimental effects associated with rib fixation. Based on these results, we do not recommend rib fixation as the standard of care for patients with multiple rib fractures. TRIAL REGISTRATION: Registered in the Netherlands Trial Register NTR6833 on 13/11/2017.

A Ziegler-type spherical cap model reveals early stage ethylene polymerization growth versus catalyst fragmentation relationships.

Polyolefin catalysts are characterized by their hierarchically complex nature, which complicates studies on the interplay between the catalyst and formed polymer phases. Here, the missing link in the morphology gap between planar model systems and industrially relevant spherical catalyst particles is introduced through the use of a spherical cap Ziegler-type catalyst model system for the polymerization of ethylene. More specifically, a moisture-stable LaOCl framework with enhanced imaging contrast has been designed to support the TiCl4 pre-active site, which could mimic the behaviour of the highly hygroscopic and industrially used MgCl2 framework. As a function of polymerization time, the fragmentation behaviour of the LaOCl framework changed from a mixture of the shrinking core (i.e., peeling off small polyethylene fragments at the surface) and continuous bisection (i.e., internal cleavage of the framework) into dominantly a continuous bisection model, which is linked to the evolution of the estimated polyethylene volume and the fraction of crystalline polyethylene formed. The combination of the spherical cap model system and the used advanced micro-spectroscopy toolbox, opens the route for high-throughput screening of catalyst functions with industrially relevant morphologies on the nano-scale.

Developing mHealth to the Context and Valuation of Injured Patients and Professionals in Hospital Trauma Care: Qualitative and Quantitative Formative Evaluations.

BACKGROUND: Trauma care faces challenges to innovating their services, such as with mobile health (mHealth) app, to improve the quality of care and patients' health experience. Systematic needs inquiries and collaborations with professional and patient end users are highly recommended to develop and prepare future implementations of such innovations. OBJECTIVE: This study aimed to develop a trauma mHealth app for patient information and support in accordance with the Center for eHealth Research and Disease Management road map and describe experiences of unmet information and support needs among injured patients with trauma, barriers to and facilitators of the provision of information and support among trauma care professionals, and drivers of value of an mHealth app in patients with trauma and trauma care professionals. METHODS: Formative evaluations were conducted using quantitative and qualitative methods. Ten semistructured interviews with patients with trauma and a focus group with 4 trauma care professionals were conducted for contextual inquiry and value specification. User requirements and value drivers were applied in prototyping. Furthermore, a complementary quantitative discrete choice experiment (DCE) was conducted with 109 Dutch trauma surgeons, which enabled triangulation on value specification results. In the DCE, preferences were stated for hypothetical mHealth products with various attributes. Panel data from the DCE were analyzed using conditional and mixed logit models. RESULTS: Patients disclosed a need for more psychosocial support and easy access to more extensive information on their injury, its consequences, and future prospects. Health care professionals designated workload as an essential issue; a digital solution should not require additional time. The conditional logit model of DCE results suggested that access to patient app data through electronic medical record integration (odds ratio [OR] 3.3, 95% CI 2.55-4.34; P<.001) or a web viewer (OR 2.3, 95% CI 1.64-3.31; P<.001) was considered the most important for an mHealth solution by surgeons, followed by the inclusion of periodic self-measurements (OR 2, 95% CI 1.64-2.46; P<.001), the local adjustment of patient information (OR 1.8, 95% CI 1.42-2.33; P<.001), local hospital identification (OR 1.7, 95% CI 1.31-2.10; P<.001), complication detection (OR 1.5, 95% CI 1.21-1.84; P<.001), and the personalization of rehabilitation through artificial intelligence (OR 1.4, 95% CI 1.13-1.62; P=.001). CONCLUSIONS: In the context of trauma care, end users have many requirements for an mHealth solution that addresses psychosocial functioning; dependable information; and, possibly, a prediction of how a patient's recovery trajectory is evolving. A structured development approach provided insights into value drivers and facilitated mHealth prototype enhancement. The findings imply that iterative development should move on from simple and easily implementable mHealth solutions to those that are suitable for broader innovations of care pathways that most-but plausibly not yet all-end users in trauma care will value. This study could inspire the trauma care community.