Literature Review of the In-Plane Behavior of Masonry Walls: Theoretical vs. Experimental Results

In-plane strength of masonry walls is affected by the resistant mechanisms activated in the walls, i.e., related to flexural or shear behavior. The latter one can occur in the walls according to different failure modes depending on both mortar and unit strengths and on the type of assembling, i.e., ‘regular’ or ‘irregular’ texture. In this paper, a critical review of the existing design formulations for the in-plane strength of masonry walls is firstly presented, with important information on the achievable failure modes depending on the geometrical and mechanical features of the masonry fabric. Then, experimental tests are collected from the literature and a comparison between theoretical and experimental results is carried out. The presented analyses are aimed to highlight the differences between the existing formulations and to identify the most suitable ones

Fibronectin-1 expression is increased in aggressive thyroid cancer and favors the migration and invasion of cancer cells

n this study we analyzed the expression levels of markers of epithelial-to-mesenchymal transition (EMT) in several papillary thyroid carcinomas (PTCs) and the relation with tumor genotypes and clinicopathological characteristics. The role of fibronectin-1 (FN1) was investigated by analyzing the effects of FN1 silencing in two human thyroid cancer cell lines. Most of EMT markers were significantly over-expressed in a group of 36 PTCs. In particular, FN1 mRNA levels were higher in tumor vs non-tumor tissue (117.3, p < 0.001) and also in aggressive and BRAF(V600E) samples. Similar results were observed (and confirmed at the protein level) when FN1 expression was analyzed in a validation group of 50 PTCs and six lymph node (LN) metastases. Silencing of FN1 in TPC-1 and BCPAP thyroid cancer cells significantly reduced proliferation, adhesion, migration, and invasion in both cell lines. Collectively, our data indicate that FN1 overexpression is an important determinant of thyroid cancer aggressiveness

Reduced expression of THRβ in papillary thyroid carcinomas: relationship with BRAF mutation, aggressiveness and miR expression

Purpose Down-regulation of thyroid hormone receptor beta (THRβ) gene has been described in several human malignancies, including thyroid cancer. In this study, we analyzed THRβ mRNA expression in surgical specimens from a series of human papillary thyroid carcinomas (PTCs), characterized by their genotypic and clinical–biological features. Methods Thirty-six PTCs were divided into two groups according to the 2009 American Thyroid Association risk classification (17 low, 19 intermediate), and each group was divided into subgroups based on the presence or absence of the BRAFV600E mutation (21 BRAF mutated, 15 BRAF wild type). Gene expression was analyzed using fluidic cards containing probes and primers specific for the THRβ gene, as well as for genes of thyroperoxidase (TPO), sodium/iodide symporter (NIS), thyroglobulin (Tg) and thyroid stimulating hormone receptor (TSH-R) and for some miRNAs involved in thyroid neoplasia and targeting THRβ. The mRNA levels of each tumor tissue were compared with their correspondent normal counterpart. Results THRβ transcript was down-regulated in all PTCs examined. No significant differences were found between intermediate- vs low-risk PTCs patients, and BRAF-mutated vs BRAF wild-type groups. THRβ expression was directly correlated with NIS, TPO, Tg and TSH-R, and inversely correlated to miR-21, -146a, -181a and -221 expression. Conclusions Our results demonstrate that down-regulation of THRβ is a common feature of PTCs. While it is not associated with a more aggressive phenotype of PTC, it correlates with the reduction of all the markers of differentiation and is associated with overexpression of some miRNAs supposed to play a role in thyroid tumorigenesis

Identification of Exosomal microRNAs and Their Targets in Papillary Thyroid Cancer Cells

The release of molecules in exosomal cargoes is involved in tumor development and progression. We compared the profiles of exosomal microRNAs released by two thyroid cancer cell lines (TPC-1 and K1) with that of non-tumorigenic thyroid cells (Nthy-ori-3-1), and we explored the network of miRNA–target interaction. After extraction and characterization of exosomes, expression levels of microRNAs were investigated using custom TaqMan Advanced array cards, and compared with those expressed in the total cell extracts. The functional enrichment and network-based analysis of the miRNAs’ targets was also performed. Five microRNAs (miR-21-5p, miR-31-5p, miR-221-3p, miR-222-3p, and let-7i-3p) were significantly deregulated in the exosomes of tumor cells vs. non-tumorigenic cells, and three of them (miR-31-5p, miR-222-3p, and let-7i-3p) in the more aggressive K1 compared to TPC-1 cells. The network analysis of the five miRNAs identified some genes as targets of more than one miRNAs. These findings permitted the identification of exosomal microRNAs secreted by aggressive PTC cells, and indicated that their main targets are regulators of the tumor microenvironment. A deeper analysis of the functional role of the targets of exosomal miRNAs will provide further information on novel targets of molecular treatments for these neoplasms

A simplified risk-targeted decision model for the verification of the seismic performance of critical infrastructure components to the operational limit state

A simplified risk-targeted decision model for the verification of the seismic performance of infrastructurecomponents to the operational limit state is presented. It assumes linearity between the intensity measure andthe engineering demand parameter and requires the evaluation of the displacement demand for a hazard-tar-geted design earthquake and of the displacement capacity. The latter is defined as the ratio between the op-erational limit-state displacement and a risk-targeted safety factor, which depends on the seismicity of the re-levant location, on the randomness of the intensity measures causing the operational limit-state, and on theacceptable (target) probability of exceeding this limit state. In the paper, the theoretical background of risk-targeted safety factor is first explained, followed by a discussion on the sensitivity of the risk-targeted safetyfactor to the input parameters. The design procedure involving the simplified risk-targeted decision model isthen introduced and demonstrated by means of an example of a simple pipe rack located at a petrochemicalplant. Within the scope of the presented example, the operational limit-state displacement of the pipe rack isestimated on thebasis of the limit-statestrains of a pipe attached to the frame. The risk-targeted safety factor isthen evaluated, and the frame is designed. It is shown that the application of the proposed procedure isstraightforward once the operational limit-state displacement has been determined. The advantage of the pro-cedure is that the target risk is accounted for by the risk-targeted safety factor, which can be calculated withrespect to the importance of the equipment of the critical infrastructure. Additionally, the proposed decisionmodelcanbeeasilyadoptedbyengineers,becausetheseismicdemandiscalculatedbyanalogytotheEurocode.However,atthisstageoftheresearch,theapplicationoftheproposeddecisionmodelislimitedtostructuresthatdo not exhibit any significant nonlinear seismic response at the operational limit state, and to structures wherethe equal displacement rule applies

Fatality risk estimation for industrialized urban areas considering multi-hazard domino effects triggered by earthquakes

The rapid expansion of the built environment has resulted in the coexistence of industrial facilities and urban centres. Following recent major earthquakes throughout the world, it has become clear that multi-hazard domino effects can significantly increase the risk of fatalities, environmental problems and losses. This complex phenomenon is not yet well understood. In this paper, the problem is treated by decomposing it into several subproblems which are described by simplified probabilistic models. These models are then coupled with the Monte Carlo method to estimate the annual probability of fatality for an individual who is continuously standing in a location of interest and to estimate fatality risk maps for an area of interest. Emphasis is placed on considering multi-hazard domino effects, which can be triggered within an industrial area due to the damage caused by earthquakes. Thus it is considered that fatalities can be caused: a) as a direct consequence of seismic damage to a unit b) as a direct physical and/or chemical consequence due to the loss of containment of hazardous material, and c) as a consequence of domino triggered by physical and chemical events such as fire, explosion, and toxic dispersion. The capabilities of the proposed methodology are demonstrated by calculating fatality risk maps for a hypothetical industrialized urban area. It is shown that disregarding multi-hazard domino effects in the estimation of fatality risk could lead to significant underestimation of the fatality risk in an industrialized urban area. Thus, it is necessary to account for multi-hazard domino effects. However, different teams of engineers can enhance the models for the probability of fatality due to various phenomena, which will improve the accuracy of the proposed methodology

Seismic Design Parameters for the Units of Industrial Facilities Considering the Performance Requirements of Built Environment

V prvem delu doktorske disertacije je predstavljen odločitveni model za preverjanje potresne zmogljivosti enote industrijskega obrata na ciljno potresno tveganje. Model obsega oceno potresnih zahtev pri projektnem potresu in oceno potresne kapacitete obravnavane enote, ki preko varnostnega faktorja implicitno zagotavlja želeno potresno zmogljivost enote z vnaprej določenim ciljnim (sprejemljivim) tveganjem. Predlagani odločitveni model je podoben modelu za preverjanje potresne zmogljivosti objektov kot ga določa standard. Zato je že poznan inženirjem, vendar ne rešuje problema opredelitve ciljnega tveganja za enote industrijskega obrata. Zaradi tega je treba projektne potresne parametre enot industrijskega obrata ovrednotiti z upoštevanjem sprejemljivega tveganja celotnega industrijsko-urbanega območja, kot je predstavljeno v drugem delu disertacije. Predlagana metodologija vključuje pet procesov: (1) analiza smrtnosti z upoštevanjem domino učinkov (npr. požari, eksplozije, širjenje strupenih snovi)(2) analiza populacije za simulacijo prostorske in časovne spremenljivosti ljudi na obravnavanem območju(3) analiza potresne nevarnosti obravnavanega območja(4) opredelitev ciljnega tveganja z letnim številom smrtnih žrtev in (5) iterativno prilagajanje ciljne funkcije ranljivosti enot industrijskega obrata. Zadnji proces vključuje razčlenitev tveganja za izgubo življenj, ki zagotavlja koristne informacije o najbolj kritičnih enotah obravnavanega sistema. Zmogljivost novega okvira za načrtovanje na ciljno tveganje je prikazana na več primerih. Izkaže se, da lahko domino učinki pomembno vplivajo na tveganje za izgubo življenj in da se lahko ciljna potresna ranljivost enot industrijskega obrata znatno razlikuje, če je cilj pri načrtovanju enot opredeljen s tveganjem za izgubo življenj na celotnem industrijsko-urbanem območju.In the first part of this thesis, a risk-targeted decision model for the verification of the seismic performance of a single industrial unit is presented. It includes the assessment of the seismic demand for a design earthquake and the seismic capacity, which is reduced by a risk-targeted safety factor. Such a safety factor implicitly guarantees the desired performance of the unit with a predefined target (acceptable) risk. The proposed risk-targeted decision model is similar to the code-based approach, which is familiar to engineers. However, it does not solve the issue of the definition of target risk for the units of an industrial facility. For this reason, the seismic design parameters for the units of an industrial facility should be evaluated for a tolerable risk considering the entire industrialised urban area, as introduced in the second part of the thesis. The proposed methodology comprises five processes: (1) fatality analysis with consideration of domino effects (e.g. fires, explosions, toxic dispersions)(2) population analysis to simulate the spatial and temporal variability of the distribution of people in the area(3) seismic hazard analysis for the location(4) definition of the tolerable risk in terms of the annual number of fatalities and (5) iterative adjustment of target fragility function of the industrial units. The last process comprises the disaggregation of the fatality risk, which provides useful information about the most critical units. The capability of the new framework for the risk-targeted design of units of an industrial facility is demonstrated by means of examples. It is shown that the domino effects can have a significant impact on the fatality risk. Moreover, the target seismic fragility functions of industrial units can vary significantly if the performance objective is defined by the fatality risk of the entire industrialised urban area

Employer Branding: How companies are attracting and retaining the best talents during the Covid-19 crisis

The digital transformation and the competitive environment have changed the way companies operate. The reputation of an enterprise has played a decisive part in attracting customers and increasing revenues as long as the competition exists. At the same time, having the best mix of talent has been recognized as the foundation for all successful companies. Indeed, The key secret in the distinction between good companies and great companies is the employees. The combination of human resources and marketing is a modern trend known as Employer branding, which is primarily meant to attract potential hires and retain current employees