Long-term (1990-2019) monitoring of forest cover changes in the humid tropics

Accurate characterization of tropical moist forest changes is needed to support conservation policies and to quantify their contribution to global carbon fluxes more effectively. We document, at pantropical scale, the extent and changes (degradation, deforestation, and recovery) of these forests over the past three decades. We estimate that 17% of tropical moist forests have disappeared since 1990 with a remaining area of 1071 million hectares in 2019, from which 10% are degraded. Our study underlines the importance of the degradation process in these ecosystems, in particular, as a precursor of deforestation, and in the recent increase in tropical moist forest disturbances (natural and anthropogenic degradation or deforestation). Without a reduction of the present disturbance rates, undisturbed forests will disappear entirely in large tropical humid regions by 2050. Our study suggests that reinforcing actions are needed to prevent the initial degradation that leads to forest clearance in 45% of the cases.

A global cloud free pixel- based image composite from Sentinel-2 data

Large-scale land cover classification from satellite imagery is still a challenge due to the big volume of data to be processed, to persistent cloud-cover in cloud-prone areas as well as seasonal artefacts that affect spatial homogeneity. Sentinel-2 times series from Copernicus Earth Observation program offer a great potential for fine scale land cover mapping thanks to high spatial and temporal resolutions, with a decametric resolution and five-day repeat time. However, the selection of best available scenes, their download together with the requirements in terms of storage and computing resources pose restrictions for large-scale land cover mapping. The dataset presented in this paper corresponds to global cloud-free pixel based composite created from the Sentinel-2 data archive (Level L1C) available in Google Earth Engine for the period January 2017- December 2018. The methodology used for generating the image composite is described and the metadata associated with the 10 m resolution dataset is presented. The data with a total volume of 15 TB is stored on the Big Data platform of the Joint Research Centre. It can be downloaded per UTM grid zone, loaded into GIS clients and displayed easily thanks to pre-computed overviews.

Automated estimation of ankle muscle EMG envelopes and resulting plantar-dorsi flexion torque from 64 garment-embedded electrodes uniformly distributed around the human leg

The design of personalized movement training and rehabilitation pipelines relies on the ability of assessing the activation of individual muscles concurrently with the resulting joint torques exerted during functional movements. Despite advances in motion capturing, force sensing and bio-electrical recording technologies, the estimation of muscle activation and resulting force still relies on lengthy experimental and computational procedures that are not clinically viable. This work proposes a wearable technology for the rapid, yet quantitative, assessment of musculoskeletal function. It comprises of (1) a soft leg garment sensorized with 64 uniformly distributed electromyography (EMG) electrodes, (2) an algorithm that automatically groups electrodes into seven muscle-specific clusters, and (3) a EMG-driven musculoskeletal model that estimates the resulting force and torque produced about the ankle joint sagittal plane. Our results show the ability of the proposed technology to automatically select a sub-set of muscle-specific electrodes that enabled accurate estimation of muscle excitations and resulting joint torques across a large range of biomechanically diverse movements, underlying different excitation patterns, in a group of eight healthy individuals. This may substantially decrease time needed for localization of muscle sites and electrode placement procedures, thereby facilitating applicability of EMG-driven modelling pipelines in standard clinical protocols.

Pan-tropical Sentinel-2 cloud-free annual composite datasets

Sentinel-2 MSI is one of the core missions of the Copernicus Earth Observation programme of the European Union. This mission shows great potential to map the regional high-resolution spatio-temporal dynamics of land use and land cover. In tropical regions, despite the high revisiting time of 5 days including both Sentinel-2A and 2B satellites, the frequent presence of clouds, cloud-shadows, haze and other atmospheric contaminants are precluding the visibility of the Earth surface up to several months. In this paper we present four annual pan-tropical cloud-free composites computed and exported from Google Earth Engine (GEE) by making use of available Sentinel-2 L1C collection for the period spanning from 2015 to 2020. We furthermore propose empirical approaches to reduce the BRDF effect over tropical forest areas by showing pros and cons of image-based versus swath-based methodologies. Additionally, we provide a dedicated web-platform offering a fast and intuitive way to browse and explore the proposed annual composites as well as layers of potential annual changes as a ready-to-use means to visually identify and verify degradation and deforestation activities as well as other land cover changes.

Automated spatial localization of ankle muscle sites and model-based estimation of joint torque post-stroke via a wearable sensorised leg garment

Assessing a patient's musculoskeletal function during over-ground walking is a primary objective in post-stroke rehabilitation, due to the importance of walking recovery for everyday life. However, the quantitative assessment of musculoskeletal function currently requires lab-constrained equipment, and labor-intensive analyses, which hampers assessment in standard clinical settings. The development of fully wearable systems for the online estimation of muscle-tendon forces and resulting joint torque would aid clinical assessment of motor recovery, it would enhance the detection of neuro-muscular anomalies and it would consequently enable highly personalized treatments. Here, we present a wearable technology that combines (1) a soft garment for the human leg sensorized with 64 flexible and dry electromyography (EMG) electrodes, (2) a generalized and automated algorithm for the localization of leg muscle sites, and (3) an EMG-driven musculoskeletal modeling framework for the estimation of ankle dorsi-plantar flexion torques. Our results showed that the automated clustering algorithm could detect muscle locations in both healthy and post-stroke individuals. The estimated muscle-specific EMG envelopes could be used to drive forward person-specific musculoskeletal models and estimate resulting joint torques accurately across all healthy and post-stroke individuals and across different walking speeds (R2  > 0.82 and RMSD  < 0.16). The technology we proposed opens new avenues for automated muscle localization and quantitative musculoskeletal function assessment during gait in both healthy and neurologically impaired individuals.

Leukemic burden in subpopulations of CD34+ cells isolated from the mobilized peripheral blood of alpha-interferon-resistant or -intolerant patients with chronic myeloid leukemia

We attempted to determine the frequency of normal hematopoietic stem cells (HSC) and contaminating leukemic cells in mobilized peripheral blood (MPB) collected from chronic myeloid leukemia (CML) patients, intolerant of alpha-interferon or with interferon-resistant disease. A total of 14 MPB samples, six from patients in chronic phase (CP) and eight from patients in accelerated phase or blast crisis (AP/BC) were studied. Cytogenetic analysis of MPB collected from AP/BC patients showed that 100% of the cells were Ph+, whereas cells from four of five CP MPB were Ph-. By contrast, fluorescence in situ hybridization (FISH) analysis of CP MPB showed a mean frequency of 14.7% Ph+ cells, while AP/BC MPB contained 39.2% Ph+ cells. In an attempt to purify normal HSC, subpopulations of the MPB CD34+ cells were isolated based on expression of the Thy-1 antigen (CDw90). The mean Ph+ cell frequency as determined by FISH within the CD34+Thy-1+Lin- and CD34+Thy-1-Lin- populations from CP patients was 19.2% and 33.9%, respectively. In the AP/BC patients, levels of residual leukemic cells were significantly greater with mean Ph+ cell frequencies of 59.2% and 72.7% for the CD34+Thy-1+Lin- and CD34+Thy-1-Lin- fractions, respectively. The frequency of cobblestone area forming cells (CAFC) was used as a means of quantitating the numbers of functional HSC within these cell subpopulations. The mean CAFC frequency was 1 of 19 for the CD34+Thy-1+Lin- cells as compared with 1 of 133 for the Thy-1-fraction indicating a higher frequency of primitive progenitor cells in the Thy-1+ subpopulation. CD34+ cell subsets from two patients were also injected into SCID-hu bone assays to determine the in vivo behavior of these cell populations. After 8 weeks, multilineage donor engraftment was observed in these grafts. FISH analysis of the donor cells within the grafts showed that 55.3% and 60.0% of the cells were Ph+. We conclude that unfractionated MPB from this patient population is not leukemia-free and that the CD34+Thy-1+Lin- cell subpopulation, although predominantly enriched for normal HSC, still contains substantial numbers of residual leukemic cells.

Management of ischemic diabetic foot

Diabetic foot pathology represent the more disabling complication of diabetes. More the 1 million of diabetes patients undergo a lower limb amputation per year; 85% of these amputation are preceded by un ulcer that can be avoided by a prevention program. Critical limb ischemia (CLI), the only independent cause of major amputation in diabetic population, can be correctly treated when an early diagnosis is made. Both endoluminal and surgical revascularization procedures can be applied in diabetes with high rate of success when performed by skilled operator. Infection of diabetic foot, in particular in patients suffering from peripheral artery disease (PVD), may rapidly evolves in severe local or systemic infection putting the patient at high risk of major amputation or death. Together with an early diagnosis of infection and ischemia it is mandatory to apply a correct medical and surgical treatment protocol with the aim to control infection and to improve blood perfusion to the foot. In case of infection surgical procedure should be applied first while revascularization procedure will follow soonest. Antibiotic therapy should be chosen considering different local biological pattern and different type of infection. Reconstructive surgery, the last step in treatment of any diabetic foot lesion, must obtain a functional residual foot or a stump that will allow the patient to go back walking soonest with residual good walking capacity.

A wearable gait lab powered by sensor-driven digital twins for quantitative biomechanical analysis post-stroke

Commonly, quantitative gait analysis post-stroke is performed in fully equipped laboratories housing costly technologies for quantitative evaluation of a patient's movement capacity. Combining such technologies with an electromyography (EMG)-driven musculoskeletal model can estimate muscle force properties non-invasively, offering clinicians insights into motor impairment mechanisms. However, lab-constrained areas and time-demanding sensor setup and data processing limit the practicality of these technologies in routine clinical care. We presented wearable technology featuring a multi-channel EMG-sensorized garment and an automated muscle localization technique. This allows unsupervised computation of muscle-specific activations, combined with five inertial measurement units (IMUs) for assessing joint kinematics and kinetics during various walking speeds. Finally, the wearable system was combined with a person-specific EMG-driven musculoskeletal model (referred to as human digital twins), enabling the quantitative assessment of movement capacity at a muscle-tendon level. This human digital twin facilitates the estimation of ankle dorsi-plantar flexion torque resulting from individual muscle-tendon forces. Results demonstrate the wearable technology's capability to extract joint kinematics and kinetics. When combined with EMG signals to drive a musculoskeletal model, it yields reasonable estimates of ankle dorsi-plantar flexion torques (R 2 = 0.65 ± 0.21) across different walking speeds for post-stroke individuals. Notably, EMG signals revealing an individual's control strategy compensate for inaccuracies in IMU-derived kinetics and kinematics when input into a musculoskeletal model. Our proposed wearable technology holds promise for estimating muscle kinetics and resulting joint torque in time-limited and space-constrained environments. It represents a crucial step toward translating human movement biomechanics outside of controlled lab environments for effective motor impairment monitoring.

Clusterization of multi-channel electromyograms into muscle-specific activations to drive a subject-specific musculoskeletal model: towards fast and accurate clinical decision-making

Current clinical decision-making is based on rapid and subjective functional tests such as 10 m walking. Moreover, greater accuracy can be achieved at the expense of rapidity and costs. In biomechanical laboratories, advanced technologies and musculoskeletal modeling can quantitatively describe the biomechanical reasons underlying gait disorders. Our work aims to blend clinical rapidity and biomechanical accuracy through multi-channel (MC) electromyography (EMG) clustering and real-time neuro-musculoskeletal (NMS) modeling techniques integrated into a sensorized wearable garment that is quick to set up. Here we present a unique pipeline that goes from MC EMG signals to ankle torque estimation following two steps: (1) non-negative matrix factorization (NNMF)-based EMG clustering for the extraction of muscle-specific activations and (2) subject-specific EMG-driven NMS modeling. The results show the potential of NNMF as an electrode clustering tool, as well as the ability to predict joint torque during movements that were not used for the EMG clustering.

Adult mesenchymal stem cells: potential for muscle and tendon regeneration and use in gene therapy

The expansion potential and plasticity of stem cells, adult or embryonic, offer great promise for their use in medical therapies. Recent provocative data suggest that the differentiation potential of adult stem cells may extend to lineages beyond those usually associated with the germ layer of origin. In this review, we describe recent developments related to adult stem cell research and in particular, in the arena of mesenchymal stem cell (MSC) research. Research demonstrates that transduced MSCs injected into skeletal muscle can persist and express secreted gene products. The ability of the MSC to differentiate into cardiomyocytes has been reported and their ability to engraft and modify the pathology in infarcted animal models is of great interest. Research using MSCs in tendon repair provides information on the effects of physical forces on phenotype and gene expression. In turn, MSCs produce changes in their matrix environment in response to those biomechanical forces. Recent data support the potential of MSCs to repair tendon, ligament, meniscus and other connective tissues. Therapeutic applications of adult stem cells are approaching clinical use in several fields, furthering the possibility to regenerate damaged and diseased tissue.