Kinetic Assessment For Selective Production of FURFURAL from C5 sugars contained in Biomass

Furfural is nowadays one of the most important biomass derived chemicals having a market of roughly 300 ktonn/year. It finds application in many chemicals sectors, being used as a solvent itself, or as starting material for almost all the furanic compounds. In a biobased economy furfural could replace or substitute many oil derivatives as platform chemical and be a starting material for liquid fuels production: furanic biofuels have lately been addressed to represent a very interesting option to current biofuels showing advantageous qualities. Moreover, being furfural derived from the C5 sugars contained in biomass, its integration in a modern biorefinery concept might represent a profitable way of valorizing the hemicellulose. Currently furfural is produced mainly through batch processes where biomass is cooked in acidic condition and furfural is stripped out by steam. Low total yields achievable in this kind of processes and high energy use drive up furfural price. A modern production process is to be developed at Delft University of Technology where furfural is produced continuously with high yields and with lower operational costs. To this aim kinetics of reaction from C5 sugars to furfural and furfural destruction in acidic water environment at temperature between 150 and 200 °C must be deeply investigated being the knowledge of C5 sugar chemistry available in literature incomplete or missing. An experimental setup has been designed and built to this scope which enables liquid phase reactions in broad range of conditions. It mainly consists of a titanium tube reactor immersed in a thermostatic oil bath where the reactants are fed by means of a HPLC pump. Mean residence time can be varied from 90 to 4500 seconds, titanium not alloyed ensures high corrosion resistance and no catalytic effects, an electrical heater at the inlet of the reactor and a pipe-in-pipe cooler at the outlet ensure steep temperature profiles. Due to these features reaction conditions and mean residence time can be accurately controlled. Experiments have being carried out using pure D-Xylose as model compound; H2SO4 is used to set H+ concentration at the desired level. Analysis is done using an HPLC apparatus equipped with UV and RI detectors. From the first experimental results a model has been proposed in which D-Xylose undergoes two parallel second order reactions in D-Xylose and H+ concentration, leading the former to furfural and the last to non identified fractionation products. The model shows a good agreement with experimental results at different temperatures and pH. Furfural degradation reaction has also been investigated at the same conditions of temperature and pH. Estimation of H+ concentration at reaction conditions is crucial and second dissociation constant of sulfuric acid dependence on temperature needs to be taken into account

Turning off the switch in medulloblastoma. The inhibitory acetylation of an oncogene

[No abstract available

Mucoepidermoid carcinoma associated with osteosarcoma in a true malignant mixed tumor of the submandibular region

True malignant mixed tumor, also known as carcinosarcoma, is a rare tumor of the salivary gland composed of both malignant epithelial and malignant mesenchymal elements. Frequently carcinosarcoma arises in the background of a preexisting pleomorphic adenoma; however, if no evidence of benign mixed tumor is present, the lesion is known as carcinosarcoma "de novo." We reported the first case of true malignant mixed tumor of the submandibular gland composed of high grade mucoepidermoid carcinoma associated with osteosarcoma. Case Presentation. A 69-year-old Caucasian male came to our department complaining of the appearance of an asymptomatic left submandibular neoformation progressively increasing in size over 3 months. We opted for surgical treatment. Histological examination confirmed the diagnosis of carcinosarcoma with the coexistence of high grade mucoepidermoid carcinoma and osteosarcoma. Conclusion. To the best of our knowledge, in the true malignant mixed tumor of the submandibular gland, mucoepidermoid carcinoma associated with osteosarcoma has never been previously reported

Targeting GLI factors to inhibit the Hedgehog pathway

Hedgehog (Hh) signaling has emerged in recent years as an attractive target for anticancer therapy because its aberrant activation is implicated in several cancers. Major progress has been made in the development of SMOOTHENED (SMO) antagonists, although they have shown several limitations due to downstream SMO pathway activation or the occurrence of drug-resistant SMO mutations. Recently, particular interest has been elicited by the identification of molecules able to hit glioma-associated oncogene (GLI) factors, the final effectors of the Hh pathway, which provide a valid tool to overcome anti-SMO resistance. Here, we review results achieved in developing GLI antagonists, explaining their mechanisms of action and highlighting their therapeutic potential. We also underline the relevance of structural details in their discovery and optimization

Phytochemistry of Commiphora erythraea: A Review:

Commiphora erythraea (Burseraceae) resin derives from the bark injury of the plant, a small tree native to the Arabian Peninsula. The resin is commonly known as myrrh and it is traditionally used to protect livestock from ticks and to treat diseases related to inflammation. The resin is constituted by a volatile and a non-volatile fraction. The volatile fraction is a source of furanosesquiterpenoids among which furanodienone showed to be the most promising pharmacological active compound. The composition and pharmacological activities of the extracts and the isolated compounds have been reviewed

Towards Sustainable Cities

Purpose – Cities drive urban, social and economic development and select a path for sustainability following a smart approach. Cities should evolve as smart communities understanding the potential of information technology to support collaboration between public and private organizations in order to improve urban competitiveness, sustain innovation and ensure the quality of life. The aim of this study is to identify the dimensions leading cities to sustainability: developing a smart approach; sustaining the role of municipal institutions for building smart governance; promoting education, learning and innovation. Design/methodology/approach – As smart communities, cities use technology to develop smartness and sustainability for knowledge and innovation. This study is based on archival and qualitative data drawn by literature review and analysis on smart and sustainable cities and communities. Originality/value – Cities promoting a smart approach should select a path for sustainability. Identifying dimensions driving cities to develop as sustainable cities and communities helps to identify knowledge source for innovation and urban growth. Practical implications – As smart and sustainable communities, cities should encourage partnerships between private and public actors in order to provide services, create and ensure high quality of life. As communities, cities should support people by sustaining learning and education, developing smart institutions of governance to design policies driving sustainable urban growth and development

Changes in Marine Seafood Consumption in Tokyo, Japan

This article examines the historical trends of Tokyo’s marine seafood consumption and tensions over how to promote urban sustainable consumption. Despite overwhelming evidence that global fish stocks are depleting, the Tokyo Metropolitan Government has not advanced an agenda to directly support sustainable seafood consumption. In this vacuum national government policies, increasing wealth, changes in preferences and private initiatives have promoted the consumption of ever larger amounts of seafood. Notwithstanding these forces, however, consumption patterns since the 1970s have changed in unpredictable ways. The per capita proportion consumed of prized, high trophic level and high status seafood, such as carnivorous fish, is declining while the consumption of other types of seafood from lower trophic levels is increasing. Moreover, seafood prices seem to play little role in these trends. Despite their great wealth and the forces that are promoting increased consumption, those living in Tokyo cannot overcome the biophysical limits posed by increasing depleted marine stocks. These results suggest an urgent need to begin implementing policies that will help lower seafood consumption at the local, national and global level to protect this resource for future generations