214 research outputs found
Influence of co-alignment procedures on the co-registration accuracy of multi-epoch SFM points clouds
The well-established spread of Remotely Piloted Aircraft Systems (RPAS) as high-performance devices in the acquisition of huge datasets has found a fertile field in the geomorphological change detection in coastal areas. The ability to retrieve image datasets with multi-epoch frequency makes them effectively incisive for planning ongoing monitoring. Considering the wide accessibility to multiple Structure-from-Motion (SfM)-3D point clouds, it follows the need for their proper management to identify a profitable co-registration approach valid for a proper comparison among them. In most cases the co-registration is inherited from the same georeferencing; in other cases, it can be done manually. Unfortunately, these methodologies are time consuming and often do not properly consider geometric errors on the models. The purpose of this research work was therefore to analyse an alternative method such as the co-alignment of sparse point clouds. Given the independently or co-aligned processed multi-epoch datasets, mean errors (ME) and root-mean-square error (RMSE) on Check Points (CPs) were evaluated by adopting different georeferencing strategies. Lastly, by first generating dense point clouds and from these the Digital Elevation Models (DEMs), scalar fields regarding DEM of Differences (DoD) were computed and allowed to localize any uncertainties δz among the estimated elevations. A cloud-to-cloud comparison was obtained using the M3C2 algorithm to extrapolate systematic georeferencing errors and the local deviation between models, an evidence of how the method can affect the detectable changes. The co-alignment methodology showed encouraging results proving to be a valid alternative to more traditional approaches
PREDICTING THE ACCURACY OF PHOTOGRAMMETRIC 3D RECONSTRUCTION FROM CAMERA CALIBRATION PARAMETERS THROUGH A MULTIVARIATE STATISTICAL APPROACH
Predicting the Accuracy of Photogrammetric 3D Reconstruction from Camera Calibration Parameters through a Multivariate Statistical Approach
Several tools have been introduced to generate accurate 3D models. Among these, Unmanned Aerial Vehicles (UAVs) are an effective low-cost tool to go beyond on-fields effort limits since they allow to fly over areas difficult to reach and to reduce the time needed to collect and process photogrammetric pictures as well. Combining their versatility with Structure from Motion (SfM) techniques efficiency has provided a widely accessible approach to generate accurate photogrammetric products. However, the outcome resolution and coherences also depend on sensor traits. Therefore, UAVs are usually equipped with low-cost non-metric cameras, with the consequent requirement for a calibration procedure to increase the final 3D models accuracy. Although several researchers have highlighted the strong impact of camera calibration parameters on the photogrammetric outcomes, their linkage has not been explored yet. This paper is aimed at investigating their relationship and to propose a novel predicting function of 3D photogrammetric reconstruction accuracy. Such function was estimated thanks to the application of the Principal Components Analysis (PCA) technique. Four photogrammetric UAV flight surveys provided the input data of PCA while an extra dataset was used to validate the results. Once PCA was completed, a synthetic index was proposed and the coefficient of determination was calculated between the index and error components. Synthetic indices values for the various datasets were applied as baseline to detect a predictive function able to assess the northern and eastern error components with a deviation of 0.005 m and 0.003 m, respectively. The proposed approach shows promising and satisfying results for predicting 3D models accuracy
Optimization of Wheat Straw Conversion into Microbial Lipids by Lipomyces tetrasporus DSM 70314 from Bench to Pilot Scale
Microbial lipids are renewable platforms for several applications including biofuels, green chemicals, and nutraceuticals that can be produced from several residual carbon sources. Lignocellulosic biomasses are abundant raw materials for the production of second-generation sugars with conversion yields depending on the quality of the hydrolysates and the metabolic efficiency of the microorganisms. In the present work, wheat straw pre-treated by steam explosion and enzymatically hydrolysed was converted into microbial lipids by Lipomyces tetrasporus DSM 70314. The preliminary optimization of the enzymatic hydrolysis was performed at the bench scale through the response surface methodology (RSM). The fermentation medium and set-up were optimized in terms of the nitrogen (N) source and carbon-to-nitrogen (C/N) ratio yielding to the selection of soy flour as a N source and C/N ratio of 160. The bench scale settings were scaled-up and further optimized at the 10 L-scale and finally at the 50 L pilot scale bioreactor. Process optimization also included oxygen supply strategies. Under optimized conditions, a lipid concentration of 14.8 gL−1 was achieved corresponding to a 23.1% w/w lipid yield and 67.4% w/w lipid cell content. Oleic acid was the most abundant fatty acid with a percentage of 57%. The overall process mass balance was assessed for the production of biodiesel from wheat straw
Optimized conversion of wheat straw into single cell oils by Yarrowia lipolytica and Lipomyces tetrasporus and synthesis of advanced biofuels
This paper deals with the optimized conversion of undetoxified wheat straw hydrolysates into microbial lipids by two oleaginous yeasts, Yarrowia lipolytica and Lipomyces tetrasporus. Wheat straw were pretreated by steam explosion at 203 degrees C for 300 s and hydrolysed at 20% solid-to-liquid ratio by using an enzymatic loading of 15 FPU/ g substrate. The mixed wheat straw hydrolysates (WHS) contained 86 gL-1 glucose and 22 gL-1 xylose, 2.3 gL-1 acetic acid, 0.9 gL-1 furanic compounds. The fermentation process was optimized in terms of the inoculum age and density, medium composition, and bioreactor feeding strategy. In particular, the different capacity of the two yeasts to overcome the toxic effect of the biomass degradation by-products, in different inoculum ages, was deeply investigated. Two hydrolysates concentration were tested: WSH containing 86 gL-1 glucose and 22 gL-1 xylose and the diluted medium containing 40 gL-1 glucose and 22 gL-1 xylose. The results indicated that both yeasts were able to detoxify WSH and grow on undetoxified hydrolysates as effect of the intrinsic capacity to metabolize the furan derivatives. Y. lipolytica was able to detoxify the medium in all the investigated set-ups, while L. tetrasporus was able to detoxify the medium only if inoculated in the stationary phase of growth. After the process optimization in shaken flasks, the production of Single Cell Oils (SCOs) by L. tetrasporus was carried out in a medium-scale bioreactor of 10L obtaining lipid yield and cell content of 21% and 62%, respectively. The extracted SCOs, with high oleic and palmitic acid content, were converted into biodiesel displaying overall features in accordance with international biodiesel standards, namely ASTM and EN 14214
A single liver metastasis from pleural biphasic mesothelioma
Virtually any malignancy can metastasize to the liver. Large solitary metastases are rare and can be difficult to distinguish from primary tumors. Malignant mesothelioma is often considered as a locally invasive cancer but tumor dissemination to extra-thoracic sites is possible, and the liver can be involved. Herein, we present a rare case of pleural mesothelioma with a solitary large liver metastasis diagnosed postmortem in a ninety-two-year-old man with 35 years of exposure to asbestos. Results of immunohistochemical staining of the pleural and liver tumor were similar, both positive for low-molecular weight keratins, calretinin, vimentin, and podoplanin, and negative for Claudin-4, TTF1, CEA, BerEP4, CK7, CK19, CK20, BAP1, Hep Par1, p40, and WT1. Fluorescent in-situ hybridization (FISH) for p16/CDKN2A was also performed and a homozygous deletion was detected in both tumors, supporting the diagnosis of mesothelioma. Reporting this case, we would like to point out that extra-thoracic dissemination from pleural mesothelioma, even if exceptional, can occur. In cases where differential diagnoses are challenging, the value of ancillary techniques and a practical approach to diagnostic work-up is of primary importance
Formalin-fixed and paraffin-embedded samples for next generation sequencing: Problems and solutions
Over the years, increasing information has been asked of the pathologist: we have moved from a purely morphological diagnosis to biomolecular and genetic studies, which have made it possible to implement the use of molecular targeted therapies, such as anti-epidermal growth factor receptor (EGFR) molecules in EGFR-mutated lung cancer, for example. Today, next generation sequencing (NGS) has changed the approach to neoplasms, to the extent that, in a short time, it has gained a place of absolute importance and diagnostic, prognostic and therapeutic utility. In this scenario, formaldehyde-fixed and paraffin-embedded (FFPE) biological tissue samples are a source of clinical and molecular information. However, problems can arise in the genetic material (DNA and RNA) for use in NGS due to fixation, and work is being devoted to possible strategies to reduce its effects. In this paper, we discuss the applications of FFPE tissue samples in the execution of NGS, we focus on the problems arising with the use of this type of material for nucleic acid extraction and, finally, we consider the most useful strategies to prevent and reduce single nucleotide polymorphisms (SNV) and other fixation artifacts
Urological melanoma: A comprehensive review of a rare subclass of mucosal melanoma with emphasis on differential diagnosis and therapeutic approaches
Melanoma is reported as the 19th most common cancer worldwide, with estimated age-standardized incidence rates of 2.8–3.1 per 100,000. Although the origin is most frequently cutaneous, mucosal melanoma has been described several times in literature, and despite its rarity (only 1% of all melanomas), increasing attention is being paid to this disease form. Within this subgroup, melanomas of the uropoetic apparatus are a rarity among rarities. Indeed, less than 50 cases of primary melanoma originating from the urinary bladder have been described, and even less originating from the kidney, renal pelvis and urethra. In this work, we present a detailed review of the literature related to this proaches. subclass of mucosal melanoma, delve into the biological landscape of this neoplasm and discuss current approaches, future perspectives and potential therapeutic approaches. Keywords: melanoma; mucosal melanoma; urology
Interview versus performance assessment of cognition as predictors of real-world outcomes in a large-scale cross-sectional study in schizophrenia
The Cognitive Assessment Interview (CAI) is an interview-based scale measuring cognitive impairment and its impact on functioning in subjects with schizophrenia (SCZ). It is approved as a coprimary measure of performance-based instruments, such as the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB). Recent research highlights negative symptoms, social cognition, and functional capacity as mediators of cognitive impairment's impact on functioning. This study compared mediation analysis outcomes using CAI or MCCB scores, providing insights into the utility of interview-based tools in research and clinical practice. The study included 618 individuals diagnosed with schizophrenia, recruited from 24 Italian psychiatric clinics. Neurocognitive assessments utilized both CAI and MCCB. Mediation analyses explored negative symptoms, social cognition, and functional capacity as mediators of the impact of neurocognition on real-life functioning domains. The study's results extend the validation of the CAI as a coprimary measure that provides valid information on the impact of cognitive impairment on real-life functioning and its possible mediators, complementing the information obtained using the MCCB. Interview-based cognitive assessment might be essential for understanding schizophrenia complexity and its impact on various cognitive and functional domains for clinicians, patients, and caregivers
Mapeamento e análise de áreas verdes urbanas em Paulínia (SP): estudo com a aplicação de geotecnologias
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