Enthalpy-temperature evaluation of slurry phase change materials with T-history method

PCMs and PCSs are widely used to increase the energy efficiency of several building elements. For example in solar thermal applications, the adoption of PCSs can increase the performance of the energy storages and efficiency of the carrier fluid. For this purpose, an important step is the definition of the enthalpy-temperature curve of the PCS. The T-History is a widely adopted method to investigate the thermal behaviour of traditional PCMs. This paper describes the T-History characterisation method for a PCS based on micro-encapsulated n-eicosane suspended in water. Some suggestions on how to deal with the specificity of PCSs are provided

EFFETTI CITOTOSSICI SINERGICI INDOTTI DALLA COMBINAZIONE SAHA/PARTENOLIDE IN CELLULE DI CARCINOMA MAMMARIO UMANO MDA-MB231

Il Partenolide (PN) \ue8 un sesquiterpene lattone, estratto dalla pianta medicinale Tanacetum Parthenium, noto per le sue propriet\ue0 antiinfiammatorie, antimicrobiche e antitumorali. A tal proposito, recentemente \ue8 stato dimostrato che il PN \ue8 in grado di esercitare un potente effetto citotossico in cellule di \u201ccarcinoma mammario umano triplo negativo\u201d (TNBC) MDA-MB231. Tuttavia quando il composto \ue8 impiegato a basse dosi determina effetti citotossici molto limitati, anche dopo lunghi periodi di trattamento. Questi risultati suggeriscono che il PN nelle cellule MDA-MB231 \ue8 in grado di indurre effetti citoprotettivi che si evidenziano quando impiegato a basse dosi. Poich\ue9 tale caratteristica potrebbe rappresentare un ostacolo al potenziale impiego in terapia del PN il mio studio \ue8 stato rivolto alla individuazione di composti in grado di potenziare l\u2019effetto di basse dosi di PN in cellule MDA-MB231. L\u2019attenzione \ue8 stata rivolta al SAHA, un inibitore delle HDAC. I risultati ottenuti hanno dimostrato che il pre-trattamento con il SAHA incrementa in modo sinergico l\u2019effetto citotossico indotto da basse dosi di PN. In particolare \ue8 interessante osservare che il PN da solo stimola la via di sopravvivenza Akt/mTOR e la traslocazione al nucleo di Nrf2, il SAHA quando impiegato da solo induce produzione di ROS e attivazione del meccanismo autofagico. Quando le cellule sono sottoposte al trattamento con l\u2019associazione dei due composti, il SAHA contrasta l\u2019attivazione del pathway Akt/mTOR indotta dal PN e quest\u2019ultimo riduce la produzione di ROS e il meccanismo autofagico indotto dal SAHA. I due composti inducono, inoltre, modifiche epigenetiche: il SAHA determina iperacetilazione degli istoni H3 e H4 e il PN riduce i livelli della DNMT1. E\u2019 interessante osservare che tali modifiche si mantengono anche quando i due composti agiscono in associazione e potrebbero essere responsabili degli incrementati livelli osservati di prodotti di geni oncosoppressori come p21 e p27 e della caduta della proteina anti-apoptotica Bcl-2 e di p65. A questi eventi si accompagna la deplezione del GSH che determina caduta del \u394\u3c8m, con conseguente fuoriuscita del citocromo c, attivazione della caspasi 3 e morte per apoptosi degli elementi cellulari

Evaluation of FHIT gene alterations in ovarian cancer.

The FHIT gene, recently cloned and mapped on chromosome 3p14.2, has frequently been found to be abnormal in several established cancer cell lines and primary tumours. As alterations of chromosome 3p are common events in ovarian cancers with breakpoint sites at 3p14.2, we decided to investigate the role of FHIT in human ovarian tumorigenesis. Fifty-four primary ovarian carcinomas were studied by reverse transcription of FHIT mRNA followed by polymerase chain reaction (PCR) amplification and sequencing of products. The same tumours and matched normal tissues were also investigated for loss of heterozygosity using three microsatellite markers located inside the gene. We found an abnormal transcript of the FHIT gene in two cases (4%) and allelic losses in eight cases (15%). Twelve (22%) of the 54 tumours investigated belonged to young patients with a family history of breast/ovarian cancer. In none of these cases was the FHITgene found to be altered. Our results indicate that FHITplays a role in a small proportion of ovarian carcinomas

The oxygen radicals involved in the toxicity induced by parthenolide in MDA-MB-231 cells

It has been shown that the sesquiterpene lactone parthenolide lowers the viability of MDA-MB-231 breast cancer cells, in correlation with oxidative stress. The present report examined the different radical species produced during parthenolide treatment and their possible role in the toxicity caused by the drug. Time course experiments showed that in the first phase of treatment (0-8 h), and in particular in the first 3 h, parthenolide induced dichlorofluorescein (DCF) signal in a large percentage of cells, while dihydroethidium (DHE) signal was not stimulated. Since the effect on DCF signal was suppressed by apocynin and diphenyleneiodonium (DPI), two inhibitors of NADPH oxidase (NOX), we suggest that parthenolide rapidly stimulated NOX activity with production of superoxide anion (O2•-), which was converted by superoxide dismutase 1 (SOD1) into hydrogen peroxide (H2O2). In the second phase of treatment (8-16 h), parthenolide increased the number of positive cells to DHE signal. Since this event was not prevented by apocynin and DPI and was associated with positivity of cells to MitoSox Red, a fluorochrome used to detect mitochondrial production of O2•-, we suggest that parthenolide induced production of O2•- at the mitochondrial level independently by NOX activity in the second phase of treatment. Finally, in this phase, most cells became positive to hydroxyphenyl fluorescein (HPF) signal, a fluorescent probe to detect highly reactive oxygen species (hROS), such as hydroxyl radical and peroxynitrite. Therefore, parthenolide between 8-16 h of treatment induced generation of O2•- and hROS, in close correlation with a marked reduction in cell viability

Novel Composites for Wing and Fuselage Applications

Design trade studies were conducted to arrive at advanced wing designs that integrated new material forms with innovative structural concepts and cost-effective fabrication methods. A representative spar was selected for design, fabrication, and test to validate the predicted performance. Textile processes, such as knitting, weaving and stitching, were used to produce fiber preforms that were later fabricated into composite span through epoxy Resin Transfer Molding (RTM), Resin Film Infusion (RFI), and consolidation of commingled thermoplastic and graphite tows. The target design ultimate strain level for these innovative structural design concepts was 6000 mu in. per in. The spars were subjected to four-point beam bending to validate their structural performance. The various material form /processing combination Y-spars were rated for their structural efficiency and acquisition cost. The acquisition cost elements were material, tooling, and labor

Evaluation of the in vitro and in vivo antineoplastic effects of Parthenolide on MDA-MB231 breast cancer cells

Triple-negative breast cancer refers to an aggressive subtype of breast cancer in which the tumor cells lack receptors for estrogen, progesterone and the HER2 protein on their surfaces. This type of breast cancer does not respond to treatments such as hormone therapy, like tamoxifen and aromatase inhibitors, or drugs that target HER2, like Herceptin. It is important, therefore, the identification of new selective drugs for the treatment of these tumors. Parthenolide (PN), a sesquiterpene lactone extracted from the medical plant Tanacetum parthenium, exerts anticancer activity on several tumor cell lines in culture, acting through diverse molecular mechanisms. Our previous studies have shown that the PN exerts strong cytotoxic effects on MG63 osteosarcoma and SK-Mel28 melanoma cells, through a caspase-independent mechanism which is associated with production of oxidative stress. Recently, we have undertaken a study in order to investigate the antineoplastic activity of PN on MDA-MB231 cells, a triple-negative breast cancer cell line. Our results demonstrated that this compound reduced the viability of MDA-MB231 cells in a dose- and time- dependent manner. This effect was not prevented by the addition of z-VAD-fmk, a general inhibitor of caspase, thus suggesting a caspase-independent cell death. Time-course experiments provided evidence that the cytotoxic effect of PN occurs in two different phases. In the first phase of treatment (8h) cells resulted positive to monodansylcadaverine (MDC), a fluorochrome that binds to autophagic vacuoles. Prolonging the treatment (16h) MDC-positive cells lowered, and an increase of PI-positive population was found, suggesting the appearance of necrotic events. The study of the mode of PN action provided evidence that treatment with parthenolide induces ROS generation, activation of JNK and inhibition of NF-kB activity. All these effects were prevented by the addition of NAC, thus suggesting the involvement of oxidative stress. The antineoplastic activity of PN has been also assayed in vivo employing diamminoparthenolide (DMAPT), a soluble analogue of PN. Nude mice bearing breast carcinoma MDA-MB231 xenografts were treated daily with DMAPT (50 mg/Kg). It was observed that DMAPT increased survival of MDA-MB231 xenograft-bearing nude mice as well as reduced MDA-MB231 xenografts tumor growth. Moreover, immunohistochemical studies showed that DMAPT was able to decrease the expression of MMP-2, MMP-9 and VEGF, all factors involved in metastatic events. These data suggest a possible use of parthenolide for the treatment of triple negative breast cancers

IoT monitoring of water consumption for irrigation systems using SEMMA methodology

The efficient use of water is an issue that has captured the attention of scientists, technicians, and the community at large. The sustainability of water resources has been threatened by the current imbalance between water supply and demand. Intelligent consumption of water would contribute to the balance and reduce the waste in applications such as the agriculture. This paper shows the design of a water consumption monitoring system based on the Internet of Things (IoT). With the implementation of this system could be known in real time the consumption of water in a crop. In addition, the user of the system may take corrective actions that optimize their water consumption; this is achieved by applying the SEMMA methodology to evaluate the data obtained by the system using two cluster algorithms, Simple K-means and GenClus++. With the application of SEMMA it was possible to determine periods of water consumption that were considered as waste in the irrigation of crops, applying data analysis with both algorithms