Tuneable 3D biocompatible scaffolds for biological and biophysical solid-tumour microenvironment studies; applications in Ovarian Cancer

Recently, three-dimensional (3D) tumour models mimicking the tumour microenvironment and reducing the use of experimental animals have been developed generating great interest to appraise tumour response to treatment strategies in cancer therapy. As tumours have distinct mechanics compared to normal tissues, biomaterials have also been utilized in 3D culture to model the mechanical properties of the tumour microenvironment, and to study the effects of extracellular matrix (ECM) mechanics on tumour development and progression. Mechanical cues regulate various cell behaviours through mechanotransduction, including proliferation, migration, and differentiation. In the context of cancer, both stromal cells (cancer associated fibroblasts) and tumour cells remodel the ECM and change its mechanical properties, and the altered mechanical niche in turn is likely to influence tumour progression. In this study, bovine derived collagen type I and Jellyfish derived marine collagen sources, were tested as biomaterial candidates for cancer studies, moulded to porous scaffolds with tuneable mechanical properties. The resulting interconnected network of collagen fibre constructs, fabricated using lyophilisation provide good control of scaffolding architecture, pore sizes range, high porosity levels, high level of cell viability and low production cost. Importantly these sponge scaffolds were, in the form of 3D models, compatible with a host of cellular and molecular biology assays used to investigate mechanical and biological effects of collagen crosslinking and (hyaluronic acid) HA inclusion on both fibroblasts and ovarian cancer cells. Stromal cells and cancer cells respond differently to the altered stiffness of their local microenvironment. Fibroblasts, once activated with TGF1, converge toward a ‘senescent-like phenotype’, blocking migration and matrix remodelling and promote tumour progression, probably through the secretion of tumour-promoting signals, in stiffer mechanical environments. Cancer cells, of both epithelial and mesenchymal phenotype, respond to increased local matrix stiffness by increasing proliferation while, at the same time, becoming more susceptible to treatment. Mechanically informative scaffolds resemble the physical characteristics of both normal and pathological ovarian tissue mechanics, where ovarian cancer originates. Physical changes observed in the later stage of ovarian cancer disease progression may therefore be fundamental for the increased cancer proliferation that drives metastatic progression, however opening an interesting window for cancer treatment. Bio-physical inclusive models not only lead the path to unveil complex interactions of biophysical and biological signals in the tumour microenvironment, but they represent a highly informative and effective platform to test novel target therapies with effective costs and high throughput. They can accommodate coculture systems and potentially patients-derived cell cultures, providing a platform to test current and new drugs and to evaluate drug efficacy following a precision medicine approach

Mechanical Studies of the Third Dimension in Cancer: From 2D to 3D Model

From the development of self-aggregating, scaffold-free multicellular spheroids to the inclusion of scaffold systems, 3D models have progressively increased in complexity to better mimic native tissues. The inclusion of a third dimension in cancer models allows researchers to zoom out from a significant but limited cancer cell research approach to a wider investigation of the tumor microenvironment. This model can include multiple cell types and many elements from the extracellular matrix (ECM), which provides mechanical support for the tissue, mediates cell-microenvironment interactions, and plays a key role in cancer cell invasion. Both biochemical and biophysical signals from the extracellular space strongly influence cell fate, the epigenetic landscape, and gene expression. Specifically, a detailed mechanistic understanding of tumor cell-ECM interactions, especially during cancer invasion, is lacking. In this review, we focus on the latest achievements in the study of ECM biomechanics and mechanosensing in cancer on 3D scaffold-based and scaffold-free models, focusing on each platform's level of complexity, up-to-date mechanical tests performed, limitations, and potential for further improvements

Examining Past, Present, and Future of Agricultural Labor: From the Bracero Program to the Coalition of Immokalee Workers

This thesis is a comparative study that examines the Bracero Program and the work of the Coalition of Immokalee Workers (CIW). The Bracero Program brought Mexican workers into the United States on temporary work visas from 1942-1964. The CIW is an organization of Mexican workers that was founded in 1992 as a response to the horrible working conditions that Mexican tomato pickers faced in Immokalee, Florida. In this thesis, I show that by putting these programs side by side, we can see the exploitation of Mexican farmworkers has relied on changing government tools—different forms of visas, different immigration regimes, different modes of regulating labor and capital. However, examining these two moments in history reveals that while these tools shift over time, there is a long history of Mexican farm-worker exploitation in the United States. We can also see that the CIW is a continuation of the kinds of activism that braceros engaged in. Scholars of the CIW attribute contemporary working conditions and forms of exploitation to the current globalized and neoliberal economies that we live with. But the Bracero Program shows that these formations are far longer than this presentist sensibility would have us believe

Context-based energy disaggregation in smart homes

In this paper, we address the problem of energy conservation and optimization in residential environments by providing users with useful information to solicit a change in consumption behavior. Taking care to highly limit the costs of installation and management, our work proposes a Non-Intrusive Load Monitoring (NILM) approach, which consists of disaggregating the whole-house power consumption into the individual portions associated to each device. State of the art NILM algorithms need monitoring data sampled at high frequency, thus requiring high costs for data collection and management. In this paper, we propose an NILM approach that relaxes the requirements on monitoring data since it uses total active power measurements gathered at low frequency (about 1 Hz). The proposed approach is based on the use of Factorial Hidden Markov Models (FHMM) in conjunction with context information related to the user presence in the house and the hourly utilization of appliances. Through a set of tests, we investigated how the use of these additional context-awareness features could improve disaggregation results with respect to the basic FHMM algorithm. The tests have been performed by using Tracebase, an open dataset made of data gathered from real home environments

Context-based energy disaggregation in smart homes

In this paper, we address the problem of energy conservation and optimization in residential environments by providing users with useful information to solicit a change in consumption behavior. Taking care to highly limit the costs of installation and management, our work proposes a Non-Intrusive Load Monitoring (NILM) approach, which consists of disaggregating the whole-house power consumption into the individual portions associated to each device. State of the art NILM algorithms need monitoring data sampled at high frequency, thus requiring high costs for data collection and management. In this paper, we propose an NILM approach that relaxes the requirements on monitoring data since it uses total active power measurements gathered at low frequency (about 1 Hz). The proposed approach is based on the use of Factorial Hidden Markov Models (FHMM) in conjunction with context information related to the user presence in the house and the hourly utilization of appliances. Through a set of tests, we investigated how the use of these additional context-awareness features could improve disaggregation results with respect to the basic FHMM algorithm. The tests have been performed by using Tracebase, an open dataset made of data gathered from real home environments

Appliance Recognition in an OSGi-based Home Energy Management Gateway

The rational use and management of energy is considered a key societal and technological challenge. Home energy management systems (HEMS) have been introduced especially in private home domains to support users in managing and controlling energy consuming devices. Recent studies have shown that informing users about their habits with appliances as well as their usage pattern can help to achieve energy reduction in private households. This requires instruments able to monitor energy consumption at fine grain level and provide this information to consumers. While the most existing approaches for load disaggregation and classification require high-frequency monitoring data, in this paper we propose an approach that exploits low-frequency monitoring data gathered by meters (i.e., Smart Plugs) displaced in the home. Moreover, while the most existing works dealing with appliance classification delegate the classification task to a remote central server, we propose a distributed approach where data processing and appliance recognition are performed locally in the Home Gateway. Our approach is based on a distributed load monitoring system made of Smart Plugs attached to devices and connected to a Home Gateway via the ZigBee protocol. The Home Gateway is based on the OSGi platform, collects data from home devices, and hosts both data processing and user interaction logic

Atti del convegno "ACNP e NILDE: comunità in movimento per la crescita dei servizi bibliotecari

ACNP e NILDE, realtà di rilevanza nazionale per lo sviluppo dei servizi bibliotecari, hanno avviato una riflessione più ampia e un confronto con le più significative esperienze nazionali e internazionali. Nelle due giornate si è discusso dell'evoluzione dei cataloghi alla luce delle esigenze di integrazione e standardizzazione, in particolare con la rete ISSN, delle novità in tema di diritto d’autore, dei servizi per la comunità degli utenti. Sono stati inoltre presentati i nuovi ambienti di lavoro NILDE e ACNP.

USAGE OF BAMBOO POWDER AS AN ADDITIVE IN ADOBE BRICKS AND BAMBOO CANES FRAME FOR THE REINFORCEMENT OF ADOBE STRUCTURE

The research shows the possibility to improve the resistance of adobe constructions using as a product, the processing waste, the bamboo powder. It can be used as additive in the mixture of the adobe bricks, increasing substantially their resistance. Those new bricks could be combined with an external reinforcement made by bamboo canes. Under normal operating conditions, the bamboo reinforcement does not collaborate with the adobe structure, but in case of strong exceptional events it is able to avoid the collapse of adobe walls. The tested solutions suit to solve many problems in crucial contexts in Latin America. In fact, this system can be built as self-construction, in environmental extremely precarious conditions, and it is also part of the traditional building knowledge of the populations to which it is addressed

Biomimetic Scaffolds Modulate the Posttraumatic Inflammatory Response in Articular Cartilage Contributing to Enhanced Neoformation of Cartilaginous Tissue In Vivo

Focal chondral lesions of the knee are the most frequent type of trauma in younger patients and are associated with a high risk of developing early posttraumatic osteoarthritis. The only current clinical solutions include microfracture, osteochondral grafting, and autologous chondrocyte implantation. Cartilage tissue engineering based on biomimetic scaffolds has become an appealing strategy to repair cartilage defects. Here, a chondrogenic collagen-chondroitin sulfate scaffold is tested in an orthotopic Lapine in vivo model to understand the beneficial effects of the immunomodulatory biomaterial on the full chondral defect. Using a combination of noninvasive imaging techniques, histological and whole transcriptome analysis, the scaffolds are shown to enhance the formation of cartilaginous tissue and suppression of host cartilage degeneration, while also supporting tissue integration and increased tissue regeneration over a 12 weeks recovery period. The results presented suggest that biomimetic materials could be a clinical solution for cartilage tissue repair, due to their ability to modulate the immune environment in favor of regenerative processes and suppression of cartilage degeneration