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Objectives To assess (I) correlations between diffusion-weighted (DWI), intravoxel incoherent motion (IVIM), dynamic contrast-enhanced (DCE) MRI, and 18F-FDG-PET/CT imaging parameters capturing tumor characteristics and (II) their predictive value of locoregional recurrence-free survival (LRFS) and overall survival (OS) in patients with head and neck squamous cell carcinoma (HNSCC) treated with (chemo)radiotherapy. Methods Between 2014 and 2018, patients with histopathologically proven HNSCC, planned for curative (chemo) radiotherapy, were prospectively included. Pretreatment clinical, anatomical, and functional imaging parameters (obtained by DWI/IVIM, DCE-MRI, and 18F-FDG-PET/CT) were extracted for primary tumors (PT) and lymph node metastases. Correlations and differences between parameters were assessed. The predictive value of LRFS and OS was assessed, performing univariable, multivariable Cox and CoxBoost regression analyses. Results In total, 70 patients were included. Significant correlations between 18F-FDG-PET parameters and DWI-/DCE volume parameters were found (r > 0.442, p

Dynamic mode atomic force microscopy phase imaging is known to produce distinct contrast between graphene areas of different atomic thickness. But the intrinsic complexity of the processes controlling the tip motion and the phase angle shift excludes its use as an independent technique for a quantitative type of analysis. By investigating the relationship between the phase shift, the tip-surface interaction, and the thickness of the epitaxial graphene areas grown on silicon carbide, we shed light on the origin of such phase contrast, and on the complex energy dissipation processes underlying phase imaging. In particular, we study the behavior of phase shift and energy dissipation when imaging the interfacial buffer layer, single-layer, and bilayer graphene regions as a function of the tip-surface separation and the interaction forces. Finally, we compare these results with those obtained on differently-grown quasi free standing single- and bilayer graphene samples.

At present high-quality protein-rich food sources are increasing to offer a sustainable alternative for the growing world population demand. Plant protein production favors biodiversity, environmental sustainability, and human health. The production of plant proteins is more cost-effective and resource-efficient compared to meat proteins since they are less exigent in terms of natural resources (nitrogen, water, etc.). The natural nitrogen fixation of legumes enriches soils and benefits cropping systems. Reducing red meat consumption and increasing consumption of protein from other sources could also increase health benefits. In this chapter we analyze the production and use of protein crops for human consumption and review their sustainability under Northern and Southern European environments.

Introduction:The novel coronavirus has spread rapidly around the world with particularly high mortality in the elderly. Care and nursing homes have become the sites of greatest concentration of cases. We intended to review 30-day mortality of COVID-19 patients with hip fractures. This is relevant given the disease impact in this age group.Methods:Medline and Embase databases were searched for relevant studies linked to mortality and morbidity in COVID-19 patients who have undergone non-elective hip surgeries using the keywords “COVID-19”OR “SARS-cov-2”OR “Coronavirus Infections”; AND “Surgery”OR “Hip”OR “Fracture”OR “Orthopedics.” We included all patients with hip fractures, but excluded pathological fractures and other non-traumatic hip pathologies. Four-hundred and eighty-one articles were identified for screening, in addition to an unpublished case-series of 67 patients that have 3 cases turned positive for COVID 19, yielding a total of 50patients for the final review.Results:The study included 4 articles published until May 9th 2020 and a case-series: 26(52%) patients were females; the median age was 86years; hypertension(53.6%), diabetes mellitus type II(28.6%), and coronary artery heart disease(25%) were the most common comorbidities; 34(68%) patients had intertrochanteric hip fracture and 16(32%) patients had femoral neck fractures; 22(59.5%) patients underwent cephalomedullary nail fixation, 12(32.4%) patients had hemiarthroplasty, and for 3(8.1%) patients, the type of surgery was not documented; 20(40%) patients died(12patients died before the surgery and 8died after surgery at a median time of 3days), 29(76.3%) patients had an unremarkable course throughout hospitalization and were discharged including 1(2.6%) patient managed non-operatively, and 1(2.6%) patient was admitted to the ICU after the surgery but eventually discharged.Conclusion:COVID-19 infected elderly patients have a higher 30-days mortality rate compared to non-COVID-19 infected cases. Further studies are warranted to look at the morbidity and mortality rates in COVID-19 positive patients with hip fractures and to investigate how these outcomes can be improved.Level of evidence:Level IV

This contribution describes the implementation of a data-driven shape optimization pipeline in a naval architecture application. We adopt reduced order models in order to improve the efficiency of the overall optimization, keeping a modular and equation-free nature to target the industrial demand. We applied the above mentioned pipeline to a realistic cruise ship in order to reduce the total drag. We begin by defining the design space, generated by deforming an initial shape in a parametric way using free form deformation. The evaluation of the performance of each new hull is determined by simulating the flux via finite volume discretization of a two-phase (water and air) fluid. Since the fluid dynamics model can result very expensive—especially dealing with complex industrial geometries—we propose also a dynamic mode decomposition enhancement to reduce the computational cost of a single numerical simulation. The real-time computation is finally achieved by means of proper orthogonal decomposition with Gaussian process regression technique. Thanks to the quick approximation, a genetic optimization algorithm becomes feasible to converge towards the optimal shape.

International audience; The unprecedented ultrahigh interlayer stiffness of supported two-layer epitaxial graphene on silicon carbide (SiC) has been recently reported by our research group. We found that under localized pressure a two-layer epitaxial graphene behaves as an ultra-hard and ultra-stiff coating, showing exceptional mechanical properties that far exceed those of bare SiC. Density functional theory (DFT) calculations indicate that this unique behavior stems from a sp 2-to-sp 3 reversible phase transition of carbon films under compression, leading to a single-layer diamond-like structure that we called diamene. In this paper, force versus indentation depth curves from high-resolution nanoindentation experiments of CVD diamond and sapphire are carried out and compared to those obtained from two-layer epitaxial graphene on SiC. These new measurements confirm that the stiffness of epitaxial graphene is larger than that exhibited by CVD diamond and sapphire substrates. Our measurements show that areas of the film consisting of buffer layer plus one, or at most two, additional graphene layers are the ones most likely to exhibit phase-changing behaviors and larger-than-diamond stiffness.

The pillarization process of Al/Fe metal oxide compound in bentonite has been carried. The study of weight adsorbent, pH, adsorption time, concentration and temperature adsorption were investigated to get the optimum condition of Congo red and Direct green removal. In addition, the pseudo kinetic and isotherm model were also determined to investigate the rate and type of adsorption. From the experiment, the optimum weight of adsorbent, pH, adsorption time, concentration and temperature were 0.3 g, 2, 45 minute, 90 mg/L, respectively. Thus, the pseudo kinetic model follow the pseudo second order while the Freundlich model was use as the isotherm model. As conclusion, The Pillarization success to enhance the adsorption capacity of bentonite to remove the Congo red and Direct green dyes.

Purpose In this study we systematically investigated different Dynamic Contrast Enhancement (DCE)-MRI protocols in the spine, with the goal of finding an optimal protocol that provides data suitable for quantitative pharmacokinetic modelling (PKM). Materials and methods In 13 patients referred for MRI of the spine, DCE-MRI of the spine was performed with 2D and 3D MRI protocols on a 3T Philips Ingenuity MR system. A standard bolus of contrast agent (Dotarem - 0.2 ml/kg body weight) was injected intravenously at a speed of 3 ml/s. Different techniques for acceleration and motion compensation were tested: parallel imaging, partial-Fourier imaging and flow compensation. The quality of the DCE MRI images was scored on the basis of SNR, motion artefacts due to flow and respiration, signal enhancement, quality of the T1 map and of the arterial input function, and quality of pharmacokinetic model fitting to the extended Tofts model. Results Sagittal 3D sequences are to be preferred for PKM of the spine. Acceleration techniques were unsuccessful due to increased flow or motion artefacts. Motion compensating gradients failed to improve the DCE scans due to the longer echo time and the T2* decay which becomes more dominant and leads to signal loss, especially in the aorta. The quality scoring revealed that the best method was a conventional 3D gradient–echo acquisition without any acceleration or motion compensation technique. The priority in the choice of sequence parameters should be given to reducing echo time and keeping the dynamic temporal resolution below 5 s. Increasing the number of acquisition, when possible, helps towards reducing flow artefacts. In our setting we achieved this with a sagittal 3D slab with 5 slices with a thickness of 4.5 mm and two acquisitions. Conclusion The proposed DCE protocol, encompassing the spine and the descending aorta, produces a realistic arterial input function and dynamic data suitable for PKM.

Background: Pharmacokinetic (PK) models can describe microvascular density and integrity. An essential component of PK models is the arterial input function (AIF) representing the time-dependent concentration of contrast agent (CA) in the blood plasma supplied to a tissue. Purpose/Hypothesis: To evaluate a novel method for subject-specific AIF estimation that takes inflow effects into account. Study Type: Retrospective study. Subjects: Thirteen clinical patients referred for spine-related complaints; 21 patients from a study into luminal Crohn's disease with known Crohn's Disease Endoscopic Index of Severity (CDEIS). Field Strength/Sequence: Dynamic fast spoiled gradient echo (FSPGR) at 3T. Assessment: A population-averaged AIF, AIFs derived from distally placed regions of interest (ROIs), and the new AIF method were applied. Tofts' PK model parameters (including v p and K trans ) obtained with the three AIFs were compared. In the Crohn's patients K trans was correlated to CDEIS. Statistical Tests: The median values of the PK model parameters from the three methods were compared using a Mann–Whitney U-test. The associated variances were statistically assessed by the Brown-Forsythe test. Spearman's rank correlation coefficient was computed to test the correlation of K trans to CDEIS. Results: The median v p was significantly larger when using the distal ROI approach, compared to the two other methods (P l 0.05 for both comparisons, in both applications). Also, the variances in v p were significantly larger with the ROI approach (P l 0.05 for all comparisons). In the Crohn's disease study, the estimated K trans parameter correlated better with the CDEIS (r = 0.733, P l 0.001) when the proposed AIF was used, compared to AIFs from the distal ROI method (r = 0.429, P = 0.067) or the population-averaged AIF (r = 0.567, P = 0.011). Data Conclusion: The proposed method yielded realistic PK model parameters and improved the correlation of the K trans parameter with CDEIS, compared to existing approaches. Level of Evidence: 3. Technical Efficacy Stage 1. J. Magn. Reson. Imaging 2018;47:1197–1204.

Background The arterial input function (AIF) represents the time-dependent arterial contrast agent (CA) concentration that is used in pharmacokinetic modeling. Purpose To develop a novel method for estimating the AIF from dynamic contrast-enhanced (DCE-) MRI data, while compensating for flow enhancement. Study type Signal simulation and phantom measurements. Phantom model Time-intensity curves (TICs) were simulated for different numbers of excitation pulses modeling flow effects. A phantom experiment was performed in which a solution (without CA) was passed through a straight tube, at constant flow velocity. Field strength/sequence Dynamic fast spoiled gradient echo (FSPGRs) at 3T MRI, both in the simulations and in the phantom experiment. TICs were generated for a duration of 373 seconds and sampled at intervals of 1.247 seconds (300 timepoints). Assessment The proposed method first estimates the number of pulses that spins have received, and then uses this knowledge to accurately estimate the CA concentration. Statistical tests The difference between the median of the estimated number of pulses and the true value was determined, as well as the interquartile range (IQR) of the estimations. The estimated CA concentrations were evaluated in the same way. The estimated number of pulses was also used to calculate flow velocity. Results The difference between the median estimated and reference number of pulses varied from -0.005 to -1.371 (corresponding IQRs: 0.853 and 48.377) at true values of 10 and 180 pulses, respectively. The difference between the median estimated CA concentration and the reference value varied from -0.00015 to 0.00306 mmol/L (corresponding IQRs: 0.01989 and 1.51013 mmol/L) at true values of 0.5 and 8.0 mmol/l, respectively, at an intermediate value of 100 pulses. The estimated flow velocities in the phantom were within 10% of the reference value. Data conclusion The proposed method accurately corrects the MRI signal affected by the inflow effect. Level of evidence 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1190-1196.

The mechanisms underlying mesenchymal stem cells’ (MSC) suppressive potency are largely unknown. We here show that highly suppressive human adipose tissue-derived MSC (AdMSC) display and induce a differential immunologic profile, upon ongoing AdMSC suppressive activity, promoting: (i) early correlated inhibition of IFN-γ and TNF-α production, along IL-10 increase, (ii) CD73+Foxp3+Treg subset expansion, and (iii) specific correlations between gene expression increases, such as: MMP9 correlated with CCL22, TNF, FASL, RUNX3, and SEMAD4 in AdMSC and, in T cells, MMP9 upregulation correlated with CCR4, IL4 and TBX21, among others, whereas MMP2 correlated with BCL2 and LRRC31. MMP9 emerged as an integrating molecule for both AdMSC and T cells in molecular networks built with our gene expression data, and we confirmed upregulation of MMP9 and MMP2 at the protein level, in AdMSC and T cells, respectively. MMP2/9 inhibition significantly decreased AdMSC suppressive effect, confirming their important role in suppressive acitivity. We conclude that MMP9 and 2 are robust new players involved in human MSC immunoregulatory mechanisms, and the higher suppressive activity correlates to their capacity to trigger a coordinated action of multiple specific molecules, mobilizing various immunoregulatory mechanisms.

Background Dynamic contrast-enhanced MRI provides information on the heterogeneity of the synovium, the primary target of disease in children with juvenile idiopathic arthritis (JIA). Objective To evaluate the feasibility of dynamic contrast-enhanced MRI in the wrist of children with JIA using conventional descriptive measures and time-intensity-curve shape analysis. To explore the association between enhancement characteristics and clinical disease status. Materials and methods Thirty-two children with JIA and wrist involvement underwent dynamic contrast-enhanced MRI with movement-registration and were classified using validated criteria as clinically active (n = 27) or inactive (n = 5). Outcome measures included descriptive parameters and the classification into time-intensity-curve shapes, which represent the patterns of signal intensity change over time. Differences in dynamic contrast-enhanced MRI outcome measures between clinically active and clinically inactive disease were analyzed and correlation with the Juvenile Arthritis Disease Activity Score was determined. Results Comprehensive evaluation of disease status was technically feasible and the quality of the dynamic dataset was improved by movement registration. The conventional descriptive measure maximum enhancement differed significantly between clinically active and inactive disease (P = 0.019), whereas time-intensity-curve shape analysis showed no differences. Juvenile Arthritis Disease Activity Score correlated moderately with enhancing volume (P = 0.484). Conclusion Dynamic contrast-enhanced MRI is a promising biomarker for evaluating disease status in children with JIA and wrist involvement. Conventional descriptive dynamic contrast-enhanced MRI measures are better associated with clinically active disease than time-intensity-curve shape analysis. Electronic supplementary material The online version of this article (doi:10.1007/s00247-016-3736-2) contains supplementary material, which is available to authorized users.

OBJECTIVES: To assess the capability of the pixel-by-pixel DCE-MRI time intensity curve (TIC)-shape analysis method in the evaluation of juvenile idiopathic arthritis (JIA) disease activity by correlating DCE-MRI parameters with semi-quantitative conventional-MRI scores of synovitis.METHODS: Clinical, laboratory, and (DCE)-MRI datasets of 85 JIA patients were prospectively obtained. TIC-shapes of each voxel were classified into one of seven predefined color-coded TIC shape categories. Spatial information on the relative amount of TIC-shapes, maximal enhancement (ME), maximal initial slope (MIS), initial area under the curve (iAUC), time-to-peak (TTP), enhancing volume (EV) was calculated of the synovial membrane. The grade of synovitis was scored on conventional MR images by two readers using the validated JAMRIS system. The Bonferroni method was used to correct for multiple testing, therefore, a P value of RESULTS: The semi-quantitative JAMRIS synovitis score correlated substantially with the ME, EV, and iAUC (Rs=0.658, PCONCLUSION: In this explorative study, both TIC shape and semi-quantitative DCE-MRI analysis methods showed moderate to substantial correlations with conventional MRI scores of disease activity, indicating that this methods are feasible. Further research is warranted whether DCE-MRI holds potential to become an objective and quantitative method for the evaluation of disease activity in JIA.

PURPOSE: The study was performed to determine whether conventional and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters of a previously affected target joint in patients with clinically inactive juvenile idiopathic arthritis (JIA) have prognostic meaning for a flare of joint inflammation during follow-up.MATERIAL AND METHODS: Thirty-two JIA patients with clinically inactive disease at the time of MRI of the knee were prospectively included. DCE-MRI provided both descriptive measures and time-intensity-curve shapes, representing functional properties of the synovium. Conventional MRI outcome measures included validated scores for synovial hypertrophy, bone marrow edema, cartilage lesions and bone erosions. During a 2-year period the patients were monitored by their pediatric rheumatologist and clinical flares were registered.RESULTS: MRI analysis revealed synovial hypertrophy in 13 (39.4%) of the clinically inactive patients. Twelve patients (37.5%) had at least one flare during 2-year clinical follow-up. Persistently inactive and flaring patients differed significantly in the maximum enhancement of the synovium on the DCE-MRI (pCONCLUSIONS: Our prospective clinical follow-up study indicates that the assessment of 'maximum enhancement' upon DCE-MRI may be able to predict a clinical flare within 2 years in inactive JIA patients.

BACKGROUND CONTEXT Pressure ulcers (PUs) are wounds initiated by pressure on the skin that blocks circulation, causing the skin and underlying tissues to die. PUs are a major health problem for bedridden patients or persons with reduced mobility; individuals with spinal cord injury (SCI) are especially more prone to developing pressure ulcers. Chronic wounds such as PUs are difficult to treat with available standard medical therapy and represent a burden on health care professionals and drain on resources and developing more effective treatments is therefore a necessity. Recent interest in the treatment of chronic wounds has shifted from a primary focus on the selection of topical dressings augmented by pharmaceutical agents to a focus on therapies designed to enhance various aspects of the wound healing cascade. Negative pressure wound therapy includes mechanical, vacuum-assisted methods that exert negative pressure of 60 to 125 mm Hg on the wound bed. Commercially available devices are typically rented and require costly consumables. This study focuses on a novel, bellows-powered negative pressure device (NPD) that is easy to apply and does not require electricity. PURPOSE The purpose of this study was to find the efficacy of negative pressure wound therapy by a novel negative pressure device for the treatment of PUs. STUDY DESIGN/SETTING This study was done at the Spinal Cord Injury Unit, Department of Orthopaedic Surgery, King George's Medical University, Lucknow, India. PATIENT SAMPLE Thirty-four spinal cord injury (SCI) cases resulting paraplegia with PUs of grade 4 were recruited in the study. All cases were equally divided in two treatment groups: 17 cases managed by negative pressure wound therapy by a novel NPD and & 17 were received wet to moist gauze dressing as standard wound care. OUTCOME MEASURES Reduction of length, width and depth of PUs, reduction of exudate and formation of healthy granulation tissue. METHODS Application of the novel NPD and all subsequent dressing-related procedures occurred at the patient's bedside. The perforated end of the drainage tube was placed on the wound surface, and its other end was extended approximately 10 cm away from the wound margin and connected to the bellows. Sterilized foam was trimmed according to the size and geometry of the wound and placed on top as a cover. The transparent film dressing was used to cover the wound and the border of adjoining healthy skin in order to achieve an airtight seal. The bellows of the NPD was charged to attain appropriate cyclical/ intermittent negative pressure. Patients and caregivers were taught how to charge the NPD and advised to charge it after every 5 to 6 hours. Standard wound care was done by wet to moist dressing with normal saline. RESULTS Wound healing outcome measures were compared at 3, 6 and 9 weeks. There were no significant changes in the length and width of PUs between the groups until week 3. Significantly reduced length and width of NPD treated PUs were found at week 6 (p=0.04) which further reduced at week 9 (p=0.001) as compared to standard wound care group cases. Similarly, significant reduction in the depth of PUs was found in the NPD treated group at week 9 (P CONCLUSIONS Negative pressure wound therapy may be the future of wound healing. Our novel negative pressure device is safe, easy to apply and efficacious in treating the pressure ulcer. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.