Problems of Channel Correlation and Statistical Bias in Photon-Correlation Spectroscopy

Correlation between channels of the normalized photocount-rate correlation function g(2)(τ) becomes significant at high count rates and leads to a number of data-analysis problems. We derive an expression for channel correlation that is valid for a detector area of arbitrary extent and compare the theoretical predictions with measured values. A data-analysis procedure is demonstrated that employs the theoretical expression for channel correlation and provides a rigorous test of an assumed fitting function. The procedure facilitates the use of the cumulant method in determining the polydispersity of scatterers. An expression for the statistical bias of g(2)(τ) is also derived and compared with measured values

Evaluation of graft success of grapevine after incubation room by means of thermographic, electrical and mechanical techniques

Grafting is an important technique for getting good yields in plant multiplication. Understanding the success of the graft after the incubation stage is important to the evaluation of the suitable grafting for the open field (nursery). Successful grafting in vines requires the development of a functional vascular system between the scion and the rootstock. The graft compatibility and its augmentation depend upon various natural factors like environment, soil conditions and protective measures. The present study examines the capability of thermographic, mechanical and electrical techniques to assess the graft quality and success after the incubation stage. The trial was carried out at Vivai Mannone, (Petrosino, Western Sicily, 37\uc2\ub042'26.28''N - 12\uc2\ub029'09.57''E). After the different tests, various grafting combinations were planted in the nursery and followed for the vegetative season. Before the evaluation procedure was performed graft unions have been subjected to a moderate heating from ambient temperature, then the thermal transient toward ambient temperature was monitored by means of a thermal imaging camera. As far as the electrical testing procedure was concerned, a sinusoidal voltage was applied through the grafts-cuttings, and the voltage attenuation at different points at increasing distances from the source was measured by an oscilloscope. The mechanical strength of the graft undergoing a controlled rate flexural loading was monitored by a PC remote controlled digital dynamometer. Experimental results show that we were able to distinguish the successful grafting only with the thermographic test. Moreover, this technique was the only non-destructive test from which it was possible to derive quantitative parameters, useful to provide successful nursery forecast. Engraftment results detected at the nursery showed a 15% error in forecast based on the proposed thermal image method, which is a satisfactory value for a feasibility study

The combination of DInSAR and facility damage data for the updating of slow-moving landslide inventory maps at medium scale

Abstract. Testing innovative procedures and techniques to update landslide inventory maps is a timely topic widely discussed in the scientific literature. In this regard remote sensing techniques – such as the Synthetic Aperture Radar Differential Interferometry (DInSAR) – can provide a valuable contribution to studies concerning slow-moving landslides in different geological contexts all over the world. In this paper, DInSAR data are firstly analysed via an innovative approach aimed at enhancing both the exploitation and the interpretation of remote sensing information; then, they are complemented with the results of an accurate analysis of survey-recorded damage to facilities due to slow-moving landslides. In particular, after being separately analysed to provide independent landslide movement indicators, the two datasets are combined in a DInSAR-Damage matrix which can be used to update the state of activity of slow-moving landslides. Moreover, together with the information provided by geomorphological maps, the two datasets are proven to be useful in detecting unmapped phenomena. The potentialities of the adopted procedure are tested in an area of southern Italy where slow-moving landslides are widespread and accurately mapped by using geomorphological criteria

Exploring 4d and 5d analysis in bim environment for infrastructures: A case study

Building Information Modelling (BIM) has emerged as a focal point in the construction industry, garnering substantial attention due to its capacity to elevate product quality, facilitate accurate quantity determination, and enhance scheduling efficiency. The inherent complexity of construction projects necessitates the integration of BIM models endowed with automation functionalities for schedules and cost estimation. This integration ensures that updates seamlessly occur throughout the construction process, thereby mitigating project uncertainties and reducing overall costs. While the potential benefits of BIM are recognized, a substantial challenge persists in the Architecture, Engineering, and Construction (AEC) field defining workflows for the automated generation of optimized 4D/5D BIM simulation and analysis. The effective utilization of BIM as a transformative tool requires addressing this challenge to unlock its full potential in project management. BIM serves as a pivotal conduit for project data, providing a structured approach to elevate overall product quality, streamline processes, and minimize contingencies and costs associated with construction projects. Consequently, the successful implementation of BIM with automated 4D/5D simulation and analysis stands as a critical milestone in advancing the capabilities of the AEC industry, ensuring greater efficiency, accuracy, and cost-effectiveness in construction projects. According to these aspects, the time-cost analysis (4D/5D) of a project for the North-South railway station in Riyadh, designed by Architect Engineer Dia Hilal, was investigated

Use of confocal microscopy imaging for in vitro assessment of adipose-derived mesenchymal stromal cells seeding on acellular dermal matrices: 3D reconstruction based on collagen autofluorescence

Background: Both mesenchymal stromal cells (MSCs) and acellular dermal matrices (ADMs) represent fascinating therapeutic tools in the wound healing scenario. Strategies aimed at combining these two treatment modalities are currently under investigation. Moreover, scarcity of quantitative, nondestructive techniques for quality assessment of engineered tissues poses great limitations in regenerative medicine and collagen autofluorescence-based imaging techniques are acquiring great importance in this setting. Objective: Our goals were to assess the in vitro interactions between ADSCs and ADMs and to analyze extracellular-matrix production. Methods: Adipose-derived MSCs (ADSC) were plated on 8-mm punch biopsies of a commercially available ADM (Integra\uae). Conventional histology with hematoxylin-eosin staining, environmental scanning electron microscopy, and confocal-laser scanning microscopy were used to obtain imaging of ADSC-seeded ADMs. Collagen production by ADSCs was quantified by mean fluorescence intensity (MFI), expressed in terms of positive pixels/field, obtained through ImageJ software processing of three-dimensional projections from confocal scanning images. Control conditions included: fibroblast-seeded ADM, ADSC- and fibroblast-induced scaffolds, and Integra\uae alone. Results: ADSCs were efficiently seeded on Integra\uae and were perfectly incorporated in the pores of the scaffold. Collagen production was revealed to be significantly higher when ADSCs were seeded on ADM rather than in all other control conditions. Collagen autofluorescence was efficiently used as a surrogate marker of ECM production. Conclusions: Combined therapies based on MSCs and collagenic ADMs are promising therapeutic options for chronic wounds. Not only ADSCs can be efficiently seeded on ADMs, but ADMs also seem to potentiate their regenerative properties, as highlightable from fluorescence confocal imaging

Poorly differentiated clusters (PDC) in colorectal cancer: Does their localization in tumor matter?

Poorly differentiated clusters (PDC) are aggregates of at least five neoplastic cells lacking evidence of glandular differentiation. By definition, they can be present at the invasive front (peripheral PDC or pPDC) and within the tumor stroma (central PDC or cPDC). In colorectal cancer (CRC), PDC are considered adverse prognosticators and seem to reflect epithelial mesenchymal transition (EMT). In this study, we have investigated the immuno-expression of two EMT-related proteins, E-cadherin and β-catenin, in PDC of primary CRCs and matched liver metastases. pPDC always showed nuclear β-catenin staining and diffusely reduced/absence of E-cadherin expression as opposed cPDC which showed nuclear β-catenin immunoreactivity and E-cadherin expression in about 50% of cases. In addition, the pattern of β-catenin and E-cadherin expression differed between PDC and the main tumor, and between primary CRC and liver metastasis (LM), in a percentage of cases. A discordant pattern of β-catenin and E-cadherin expression between pPDC and cPDC, between main tumor and cPDC, and between primary CRC and LM, confirms that EMT is a dynamic and reversible process in CRC. On the overall, this suggests that pPDC and cPDC are biologically different. We may advocate that PDC develop at the tumor center (cPDC) and then some of them migrate towards the tumor periphery while progressively completing EMT process (pPDC). Based on these results, PDC presence and counting may have different prognostic relevance if the assessment is done at the invasive front of the tumor or in the intratumor stroma

Titanium Surface Properties Influence the Biological Activity and FasL Expression of Craniofacial Stromal Cells.

Mesenchymal stromal cells (MSCs) can be easily isolated form craniofacial bones during routine dentistry procedures. Due to their embryological origin from neural crest, they represent a suitable cell population to study cell-biomaterial interaction in the craniofacial field, including osteoinductive/osteointegrative processes. The biological and immunomodulatory properties of MSCs may be influenced by chemistry and topography of implant surfaces. We investigated if and how three different titanium surfaces, machined (MCH), sandblasted with resorbable blasting medium (RBM), and Ca++-nanostructured (NCA), may affect biological activity, osseointegration, and immunomodulatory properties of craniofacial MSCs. Cell proliferation, morphology, osteogenic markers, and FasL were evaluated on MSCs isolated from the mandibular bone after seeding on these three different surfaces. No statistically significant differences in cell proliferation were observed whereas different morphologies and growth patterns were detected for each type of surface. No difference in the expression of osteogenic markers was revealed. Interestingly, FasL expression, involved in the immunomodulatory activity of stem cells, was influenced by surface properties. Particularly, immunofluorescence analysis indicated that FasL expression increased on MCH surface compared to the others confirming the suggested role of FasL in promoting osteogenic differentiation. Titanium surface treatments and topography might reflect different biological behaviours of craniofacial MSCs and influence their osseointegration/immunomodulation properties