A contribution of in situ UV/Vis/NIR spectroscopy to characterize molybdenum oxide catalysts

Molybdenum oxide based catalysts are suitable candidates for many selective oxidation reactions [1]. Such catalysts containing only Mo and O have been successfully prepared by controlled adjustment of precursor concentration, temperature or nature of counter cation. The obtained materials, namely orthorhombic and hexagonal MoO3, a supramolecular Mo36 and a trimolybdate compound were thoroughly analysed by XRD, TEM, TG, TPRS and Raman spectroscopy [2]. As such materials undergo electronic changes during catalytic reactions we will present an in situ UV/Vis/NIR study on the different families of molybdenum oxide (MoOx) catalysts. Experimental A commercial UV/Vis/NIR spectrometer (Lambda 9, Perkin Elmer) equipped with a BaSO4 coated integrating sphere was supplemented with a new construction (specially formed light conductor in vertical position) to measure in situ diffuse reflectance spectra of different MoOx from room temperature (RT) to 673 K [3]. The spectra were recorded both from 250 to 2500 nm (scan speed of 240 nmmin-1, slit 1 nm) and 250 to 800 nm (scan speed 60 nmmin-1, slit 0.2 nm) with Spectralon (Labsphere) as a white standard in the reference position. Powder samples (ca. 0.6 g) were charged in the home-made microreactor and fed with a flow of air, pure He or 21 % oxygen in helium. The MoOx samples were prepared using precipitation method (0.28 up to 2 mol/L AHM, Na2MoO4, K2MoO4, Li2MoO4 dissolved in bi-distilled water and 1 mol/L up to 5 mol/L HNO3) from 30oC to 70oC. Results and discussion MoOx spectra show NIR bands with different intensities, distinguishable LMCT bands and band gap energies (Eg) at RT. Based on the exact determination of such spectroscopic characteristics the following LMCT bands (nm) (I) and Eg’s (eV) (II) are attributed to the above mentioned MoOx families: (I) 322 (NH4+), 314 (K+); (II) 3.48 (NH4+), 3.44 (K+) to supramolecular Mo36; (I) 313 (NH4+), 319 (K+), 327 (Na+); (II) 3.35 (NH4+); 3.30 (K+), 3.27 (Na+) to hexagonal MoO3; (I) 296 (Li+); (II) 3.44 (Li+) to orthorhombic MoO3 and (I) 284 (K+); (II) 3.77 (K+) to trimolybdate MoOx. From a blue shift of the LMCT band in the series supramolecular/hexagonal orthorhombic trimolybdate and a decreasing broadening of this band it may be concluded that the cluster size decreases. All MoOx samples evolved NIR bands at 1435, 1940, and 2040 nm. They are assignable to an overtone mode of the OH stretching vibration and a combination mode of the OH stretching and bending vibration, respectively. Other NIR bands, e.g., those detected in MoOx samples prepared from AHM at 1570 and 2150 are caused by ammonia. Initial experiments in dependence on temperature show that the bands at 1440, 1940 and 2030 nm initially decrease at higher temperature and then disappear. In addition, by increasing the temperature the band at 2150 nm begins to disappear at 553 K and the band at 1570 nm dimi- nished around 633 K (not shown). In Vis range a new band at 660/670 nm develops at 553 K which decreases in presence of He and increases in presence of O2 in He with increasing temperature (Fig. 1). This band is assigned to a d-d transition. In He this band suffers a blue shift to about 570 nm at 673 K. The appearance of the new Vis band can be correlate with TG/DSC data. At 553 K ammonia as counter ion de- composes to NOx and reduces the Mo matrix; ammonia is completely removed from the sample at around 693 K

Preparation and characterisation of single phase (MoVW)₅O₁₄-type catalyst material

MoVW based materials are highly effective catalysts for partial oxidation reactions such as conversion of acrolein to acrylic acid. They offer a high selectivity, high yields and a good long term stability. Preceding work has identified the catalytically active phase of the MoVW catalyst and characterised it by Raman spectroscopy. The current work has been carried out to synthesise and characterise this active (MoVW)5O14 type structure

Education for innovation and entrepreneurship in the food system: the Erasmus+ BoostEdu approach and results

Innovation and entrepreneurship are key factors to provide added value for food systems. Based on the findings of the Erasmus+ Strategic Partnership BoostEdu, the objective of this paper is to provide answers to three knowledge gaps: 1) identify the needs for innovation and entrepreneurship (I&E) in the food sector; 2) understand the best way to organize learning; 3) provide flexibility in turbulent times. BoostEdu aimed to provide a platform for continuing education within I&E for food professionals and was carried out through co-creation workshops and the development of an e-learning course. The results of the project in particular during the Covid-19 pandemics, highlighted the need for flexible access to modules that are complementary to other sources and based on a mix of theoretical concepts and practical experiences. The main lessons learned concern the need of co-creation and co-learning processes to identify suitable practices for the use of innovative digital technologies

Pioglitazone Treatment Increases Survival and Prevents Body Weight Loss in Tumor-Bearing Animals: Possible Anti-Cachectic Effect

Cachexia is a multifactorial syndrome characterized by profound involuntary weight loss, fat depletion, skeletal muscle wasting, and asthenia; all symptoms are not entirely attributable to inadequate nutritional intake. Adipose tissue and skeletal muscle loss during cancer cachexia development has been described systematically. the former was proposed to precede and be more rapid than the latter, which presents a means for the early detection of cachexia in cancer patients. Recently, pioglitazone (PGZ) was proposed to exhibit anticancer properties, including a reduction in insulin resistance and adipose tissue loss; nevertheless, few studies have evaluated its effect on survival. for greater insight into a potential anti-cachectic effect due to PGZ, 8-week-old male Wistar rats were subcutaneously inoculated with 1 mL (2x10(7)) of Walker 256 tumor cells. the animals were randomly assigned to two experimental groups: TC (tumor + saline-control) and TP5 (tumor + PGZ/5 mg). Body weight, food ingestion and tumor growth were measured at baseline and after removal of tumor on days 7, 14 and 26. Samples from different visceral adipose tissue (AT) depots were collected on days 7 and 14 and stored at -80oC (5 to 7 animals per day/group). the PGZ treatment showed an increase in the survival average of 27.3%(P<0.01) when compared to TC. It was also associated with enhanced body mass preservation (40.7 and 56.3%, p<0.01) on day 14 and 26 compared with the TC group. the treatment also reduced the final tumor mass (53.4%, p<0.05) and anorexia compared with the TC group during late-stage cachexia. the retroperitoneal AT (RPAT) mass was preserved on day 7 compared with the TC group during the same experimental period. Such effect also demonstrates inverse relationship with tumor growth, on day 14. Gene expression of PPAR-gamma, adiponectin, LPL and C/EBP-alpha from cachectic rats was upregulated after PGZ. Glucose uptake from adipocyte cells (RPAT) was entirely re-established due to PGZ treatment. Taken together, the results demonstrate beneficial effects of PGZ treatment at both the early and final stages of cachexia.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Mogi das Cruzes, Integrated Grp Biotechnol, Lab Adipose Tissue Biol, Mogi Das Cruzes, BrazilUniv São Paulo, Inst Biomed Sci, Canc Metab Res Grp, São Paulo, BrazilUniv São Paulo, Inst Biomed Sci, Physiol Lab, São Paulo, BrazilUniv Estadual Maringa, Dept Physiol Sci, Maringa, Parana, BrazilUniversidade Federal de São Paulo, Dept Biomed Engn, Sao Jose Dos Campos, BrazilBoston Sch Med, Dept Biochem, Boston, MA USAUniversidade Federal de São Paulo, Dept Biomed Engn, Sao Jose Dos Campos, BrazilFAPESP: 2010/51078-1FAPESP: 2008/54091-9FAPESP: 2012/51094-1Web of Scienc

Analysis of the Virulence of an Atypical Enteropathogenic Escherichia coli Strain In Vitro and In Vivo and the Influence of Type Three Secretion System

Atypical enteropathogenic Escherichia coli (aEPEC) inject various effectors into intestinal cells through a type three secretion system (T3SS), causing attaching and effacing (A/E) lesions. We investigated the role of T3SS in the ability of the aEPEC 1711-4 strain to interact with enterocytes in vitro (Caco-2 cells) and in vivo (rabbit ileal loops) and to translocate the rat intestinal mucosa in vivo. A T3SS isogenic mutant strain was constructed, which showed marked reduction in the ability to associate and invade but not to persist inside Caco-2 cells. After rabbit infection, only aEPEC 1711-4 was detected inside enterocytes at 8 and 24 hours pointing to a T3SS-dependent invasive potential in vivo. In contrast to aEPEC 1711-4, the T3SS-deficient strain no longer produced A/E lesions or induced macrophage infiltration. We also demonstrated that the ability of aEPEC 1711-4 to translocate through mesenteric lymph nodes to spleen and liver in a rat model depends on a functional T3SS, since a decreased number of T3SS mutant bacteria were recovered from extraintestinal sites. These findings indicate that the full virulence potential of aEPEC 1711-4 depends on a functional T3SS, which contributes to efficient adhesion/invasion in vitro and in vivo and to bacterial translocation to extraintestinal sites

Undertaking Rehabilitation Research During the COVID-19 Pandemic: Emergent Strategies From a Trainee-Faculty Workshop

BackgroundThe COVID-19 pandemic has disrupted everyday rehabilitation research. Many academic institutions have halted in-person human research including rehabilitation sciences. Researchers are faced with several barriers to continuing their research programs. The purpose of this perspective article is to report the results of an interdisciplinary workshop aimed at understanding the challenges and corresponding strategies for conducting rehabilitation research during the COVID-19 pandemic.MethodsTwenty-five rehabilitation researchers (17 trainees and eight faculty) attended a 2-h facilitated online workshop in to discuss challenges and strategies they had experienced and employed to conduct rehabilitation research during the COVID-19 pandemic.ResultsRehabilitation researchers reported challenges with (1) pandemic protocol adjustments, (2) participant accessibility, and (3) knowledge dissemination, along with corresponding strategies to these challenges. Researchers experienced disruptions in study outcomes and intervention protocols to adhere to public health guidelines and have suggested implementing novel virtual approaches and study toolkits to facilitate offsite assessment. Participant accessibility could be improved by engaging community stakeholders in protocol revisions to ensure equity, safety, and feasibility. Researchers also experienced barriers to virtual conferences and publication, suggested opportunities for smaller networking events, and revisiting timeframes for knowledge dissemination.ConclusionThis perspective article served as a catalyst for discussion among rehabilitation researchers to identify novel and creative approaches that address the complexities of conducting rehabilitation research during the COVID-19 pandemic and beyond

Os livros brancos da defesa da República Popular da China 1998-2010

Este estudo é uma análise da evolução das perceções de (in)segurança da República Popular da China (RPC), através da aferição quantitativa e qualitativa de expressões idiomáticas caracterizadoras da evolução do sistema internacional, as quais foram selecionadas e associadas a tais perceções, e que constam das sete edições do Livro Branco da Defesa publicadas pelo Conselho de Estado entre 1998 e 2010. Procura-se através de um enquadramento conceptual e metodológico derivado da análise crítica do discurso baseado nas teorias de Michel Foucault e de Norman Fairclough, bem como do da perceção de ameaças por parte dos Estados no sistema internacional formulado por Robert Jervis, identificar e justificar variações nas perceções de (in)segurança da RPC entre 1998 e 2010, concluindo-se que estas refletem uma visão de natureza essencialmente realista estrutural e Lockeana quanto à evolução do sistema internacional