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Various international perspectives from selected regions where substantial work is being done on green and sustainable chemistry education emphasize a systems thinking framework. Common to most of the perspectives is the inclusion of more global paradigms involving economic, environmental, political, and social aspects as fundamental issues in the formerly merely technical and scientific discussions, as well as the development of laboratory experiences, training sessions, written materials, discussion meetings, and conferences. We include bird’s eye views from Europe (the Green Chemistry Centre of Excellence at the University of York, United Kingdom; the University of Cordoba, Spain; and the University of Amsterdam, The Netherlands), Latin America (the Universidad Nacional de Rosario, Argentina, and the Universidad Iberoamericana, Mexico), Africa (the University of Venda, South Africa), and Australia (Monash University).

This study has been conducted with financial support received from Excellence Research Project P12-SEJ-1980 of the Andalusia Regional Government and Project ECO2012- 39576 of Spanish Ministry of Economy and Competitiveness. For financial institutions mobile banking has represented a breakthrough in terms of remote banking services. However, many customers remain uncertain due to its security. This study develops a technology acceptance model that integrates the innovation diffusion theory, perceived risk and trust in the classic TAM model in order to shed light on what factors determine user acceptance of mobile banking applications. The participants had to examine a mobile application of the largest European bank. In the proposed model, an approach to external influences was included, theoretically and originally stated by Davis et al. (1989). The proposed model was empirically tested using data collected from an online survey applying structural equation modeling (SEM). The results obtained in this study demonstrate how attitude determine mainly the intended use of mobile apps, discarding usefulness and risk as factors that directly improve its use. Finally, the study shows the main management implications and identifies certain strategies to reinforce this new business in the context of new technological advances. Para las entidades financieras la banca para móviles ha representado una innovación en términos de servicios de banca remota. Sin embargo, muchos clientes siguen considerando incierta su seguridad. Este estudio desarrolla un modelo de aceptación tecnológica que integra, en el modelo TAM clásico, la teoría de la difusión de la innovación, el riesgo percibido y la confianza, a fin de clarificar qué factores determinan la aceptación de las aplicaciones de banca para móviles por parte del usuario. Los participantes tuvieron que examinar una aplicación para móviles perteneciente al mayor banco europeo. En el modelo propuesto, se incluyó una aproximación hacia las influencias externas, que fue establecida de manera teórica y original por parte de Davis et al. (1989). El modelo propuesto se testó empíricamente utilizando la información recolectada mediante una encuesta online, aplicando el modelo de ecuaciones estructurales (SEM). Los resultados obtenidos en el estudio demuestran el modo en que la actitud determina principalmente el uso previsto de las aplicaciones para móvil, descartando la utilidad y el riesgo como factores que mejoran directamente su uso. Por último, el estudio muestra las principales implicaciones para la gestión, e identifica ciertas estrategias de refuerzo de este nuevo negocio en el contexto de los nuevos avances tecnológicos. Excellence Research Project P12-SEJ-1980 of the Andalusia Regional Government Project ECO2012- 39576 of Spanish Ministry of Economy and Competitiveness

Background Therapeutic drug monitoring (TDM) postinduction of vedolizumab (VDZ) could have relationship with long-term outcome of inflammatory bowel disease (IBD) patients. However, clinical utility of TDM during maintenance VDZ therapy remains unclear. To examine the association of induction and maintenance vedolizumab though levels (VTL) with clinical and biochemical long-term outcome in IBD patients. Methods We performed a retrospective cohort study, including all consecutive IBD patients of our centre on VDZ treatment who had VTL and anti-vedolizumab antibodies (AVA) measured during induction and maintenance therapy. All patients had received a minimum of 6 weeks therapy following standard induction (0, 2, 6 ± 10 week dosing. Clinical response and remission were defined by Partial Mayo Score (PMS, UC) or Harvey Bradshaw Index (HBI, CD) and were assessed at week 52.Biochemical remission was defined as CRP < 0.5 g/dl and faecal biomarker remission as faecal calprotectin (FC) < 250 µg/g. Measurement of VTL and AVA was performed by ELISA assays(Vedolizumab-TheraDiag(R) with a detection limit for VTL of 2 μg/ml and measurement range of 2–60 μg/ml. Results In total, 34 patients were included (55.9% UC; 44.1% CD, 50% women). Median age was 52.76(17–83) and mean disease duration was 8 ± 7.2 years. Median baseline HBI was 6(0–12) and PMS was 5(3–7). FC and CRP measured before first dose of VDZ were 1425 ± 1189 μg/g and 2.1 ± 2.4 mg/dl. A total of 14 patients (41.2%) were naïve for biologic therapy. Only three patients (8.8%) were receiving a concomitant immunomodulator. Clinical response to induction phase was reported in 76%. Clinical remission, clinical response, biochemical remission and faecal biomarker remission were present in 30% (9/29), 41.4% (12/29), 40.9% (9/22) and 35% (7/20), respectively, at week 52. Thirteen patients (13/26, 50%) needed dose escalation at week 52. Twenty-six patients (78.8%) were persistent in VDZ therapy at the end of the study. The median level of VDZ at weeks 6 and 24 were 16.13 ± 7.06 μg/ml and 9.6 ± 6.7 μg/ml. Comparing patients with and without clinical response or remission to VDZ at week 52 no significant difference in VTL was found at Week 6 (16.27 vs. 15.46 μg/ml, p = 0.8) and week 24 (7.6 vs. 12.7 μg/ml, p = 0.1). No difference was observed in VTL in patients in biochemical remission (week 6: 23.6 vs. 15.7 μg/ml, p = 0.2; week 24: 10.3 vs. 10.2 μg/ml, p = 0.9) or with faecal biomarker remission (week 6: week 6: 25.5 vs. 16.2 μg/ml, p = 0.1; week 24: 10.7 vs. 8.2 μg/ml, p = 0.6) at week 52. No patient developed antibodies. Conclusion In this real-world study of IBD patients receiving VDZ, early induction or maintenance VTL are not associated with long-term outcome.

The microwave-assisted conversion of levulinic acid (LA) has been studied using low-loaded supported Fe-based catalysts on porous silicates. A very simple, productive, and highly reproducible continuous flow method has been used for the homogeneous deposition of metal oxide nanoparticles on the silicate supports. Formic acid was used as a hydrogen donating agent for the hydrogenation of LA to effectively replace high pressure H2 mostly reported for LA conversion. Moderate LA conversion was achieved in the case of non-noble metal-based iron oxide catalysts, with a significant potential for further improvements to compete with noble metal-based catalysts

SBA-15 materials exhibit important properties including large surface area, highly ordered mesopores, and high stability in a variety of catalytic reactions. In this study, Al and Zr-loaded SBA-15 materials (Si/Zr = 30, Si/Al = 30), 50 molar ratio with Pd (1, 2, and 4% (w/w)) and Pt (0.5 and 1% (w/w)) were tested in the isomerization of C5-C7 linear alkanes. These solids were characterized using thermal gravimetric analysis-differential thermal analysis (TGA-DTA), nitrogen physisorption, and energy dispersive X-ray (EDX). Interestingly, the low porosity SBA-15 materials loaded with 2% (w/w) Pd were most active catalysts for n-heptane isomerization. The mechanochemical addition of tungsten also resulted in the increase of catalytic activity for the reaction. The results herein demonstrate the possibilities of SBA-15 catalysts as a commercial catalyst alternative in the catalytic isomerization of hydrocarbons.

Catalytically active supported metal nanoparticles on aluminosilicates including Cu and Pd-based systems were investigated in the microwave-assisted conversion to a range of valuable furanic compounds via tandem formic acid-promoted dehydration and subsequent selective hydrogenation processes. Results show that interesting selectivities to reduced products including 5-methylfurfural and 5-methylfurfuryl alcohol as well as hydroxymethylfurfural and furfural could be obtained in various proportions depending on the type of catalyst and the investigated reaction conditions. The investigation of reaction parameters including time of reaction, type of catalyst, quantity of catalyst and formic acid content indicated that reaction conditions can in principle be fine-tuned to maximise selectivity towards individual products.

The level of science skills in Spanish students are significantly below the average of the Organisation for Economic Co-operation and Development, and university teachers agree that the level of freshmen students’ skills is too low. Moreover, the number of engineering enrollments has been declining in recent years. The purpose of this study is to improve both the level of knowledge and skills of students upon entrance into engineering programs and their general opinion about engineering studies. The aim is to establish the importance of proper coordination between groups involved in the overall educational process and to avoid, at least in part, the decline in recent engineering enrollments. The project had the following four phases: (1) determination of the freshmen’s weakest concepts; (2) assessment of high schools students’ knowledge; (3) development of educational activities; and (4) re-assessment of high school students. These measures were complemented with the high school teachers’ opinions about the students improvements and analyses of the evolution of engineering enrollments. Most of the participants significantly improved their knowledge and skills. Similarly, high school teachers believed that the attitude of the students toward engineering improved significantly.

A novel congenital syndrome in lambs is described that is characterized by: (1) kyphoscoliosis (severe curvature, hunching and twisting of the thoracic spine, with associated abnormalities of the ribs and sternum), (2) distal arthrogryposis of the carpal and tarsal joints, and (3) cleft hard and soft palate or palatoschisis (a median fissure of the palate). Male and female lambs are affected equally and in multiple births there may be only one affected lamb. The affected lambs are born full term, but die shortly after birth because they are unable to start breathing. Affected lambs have slightly reduced bodyweight (due to low muscle mass) compared with normal newborn lambs of the same flock. The syndrome is remarkably similar to the recently described bovine heritable arthrogryposis multiplex congenita in the Angus breed. Genetic analysis of the flock by means of DNA microsatellite markers, together with study of the reproductive management of the flock, allowed us to discount an environmental aetiology (e.g. intoxications or infections). In contrast, evidence supports an autosomal recessive inherited disease for which the name ovine heritable arthrogryposis multiplex congenita is proposed.

Iron-modified AlPO4 catalysts (0.5–5 wt.% Fe2O3) have been prepared by impregnation until incipient wetness with different iron(III) salts. The resulting solids, after characterization by surface area, XRD and DRIFT measurements, were checked for their surface acidity through their catalytic activity towards cyclohexene skeletal isomerization test reaction. It was found that iron(III) increases the catalytic performance of AlPO4 and besides, the iron(III) salt used strongly influences the activity. Thus, the catalysts prepared using complexed iron(III) salts as starting materials presented higher specific activity (and hence, acidity) than those prepared using iron(III) nitrate. Moreover, a maximum in activity was found for 2 wt.% Fe2O3.

The Michael addition of nitromethane to 3-buten-2-one has been carried out in the absence of solvent, using potassium fluoride supported on Al2O3, ZnO, SnO2, sepiolite, AlPO4, AlPO4−Al2O3 and AlPO4−ZnO catalysts. We found that KF/ZnO easily performed the Michael addition and thus, ZnO is a better support for the basic reagent than Al2O3. Besides, the Michael addition was not successful with AlPO4 or AlPO4-metal oxide acidic supports.

Summary AA amyloidosis was initiated experimentally in adult sheep by induction of gangrenous pneumonia, an inflammatory process known to be associated with amyloid formation. A vegetable fragment contaminated with rumen content was instilled into the lungs of 4 experimental animals. A fifth animal was not inoculated and served as control. The animals were examined daily and blood and urine were sampled biweekly post-inoculation. One sheep was killed 18 days post-inoculation (dpi), another 49 dpi, and the remaining two (as well as the control animal) 63 dpi. Respiratory signs, diarrhoea and/or soft, unformed stool were observed in all inoculated sheep. All experimental animals developed gangrenous pneumonia with hypoalbuminaemia and hypergammaglobulinaemia, and elevated urinary protein, creatinine, gamma glutamyl transferase and s-glucuronidase. Amyloid deposition was most pronounced in the gastrointestinal tract and was evident from 18 dpi. Amyloid was present from the tongue to the rectum, but was most prominent in the duodenum where the deposits disrupted the normal mucosal architecture. Other body organs had only mild amyloid deposition. Immunohistochemistry confirmed that the deposits were AA amyloid. These findings suggest that the gastrointestinal tract is the main target organ for AA amyloid deposition in sheep. The observations in this experimental model must now be confirmed in animals with spontaneously arising AA amyloidosis.

Fourteen hydrops fetalis cases appeared in a sheep flock in the Soria province of Central Spain in two lambing seasons in 2000. There were no previous cases of hydrops fetalis in this flock. Normal delivery could not be completed because fetal weights ranged from 12 to 16 kg and fetuses had massive subcutaneous edema. Five affected pregnant females were studied. The complete lack of lymph nodes in the fetuses was the most outstanding finding, this anomaly likely being the origin of generalized fluid accumulation. Karyotypes were normal. A blind protocol of parentage testing was performed by means of DNA microsatellite analysis, and one of the five existing rams was found to be the only compatible sire of the affected fetuses. This male had been selected from the same flock while the other rams had all been acquired from other farms. The first cases appeared when this ram began breeding, and no cases were observed after replacing it. Male and female fetuses were affected in similar proportions. The existence of a recessive allele affecting normal lymph node embryonic development in this flock is proposed as the most appropriate hypothesis. As a consequence, the use of rams from different farms is indicated as an efficient emergency measure in similar situations, while the affected flock should be excluded from selection programs as long as the anomalous gene remains unidentified.

Focal abnormalities of gyration (FAG) are developmental disorders that may occur in isolated patients or, as in the case being reported, as part of a familial disorder. Analysis of individuals in a family spanning three generations was carried out using MRI. Abnormalities, present in all members of generations II and III, included focal cortical dysplasia (three patients), focal cortical infolding (two patients) and schizencephaly (one patient); associated minor anomalies, such as white matter abnormalities, were seen in the remaining three members of generations II and III. MRI recognition of FAG in the family being reported proved useful in defining their phenotypical expression and providing proper counselling for individual family members.

A series of FePO4(Fe/P = 1) catalysts have been prepared by precipitation of the corresponding chloride or nitrate iron(III) salt and orthophosphoric acid with aqueous ammonia or propylene oxide at pH 7.0. The resulting solids, after calcination at temperatures in the range 673–1273 K for 3 h, were characterized by surface area, X-ray diffraction (XRD) and diffuse reflectance IR (DRIFT) measurements.All catalysts were amorphous for calcination temperatures below 923 K. Calcination at 923–1273 K develops FePO4 with a quartz-like phase structure (ASTM 29–715). Amorphous samples exhibited relatively high surface areas which fell sharply as crystallization of FePO4 occurred. Moreover, the surface acidity (Bronsted and Lewis), characterized by adsorption of pyridine using a pulse method and DRIFT measurements, strongly depended on the preparation method causing the amorphous FePO4 catalysts, obtained from iron(III) chloride and aqueous ammonia, to be more acidic. This increased surface Bronsted acidity was responsible for their improved performance in cyclohexene skeletal isomerization (CSI). FePO4 catalysts also showed catalytic activity for cyclohexene dehydrogenation to benzene.

The nature of supported KMnO4 reagents on several solids (SiO2 AlPO4, BPO4 and sepiolite) is discussed. The oxidation of PhCHO to PhCO2H was the test reaction. The KMnO4 supported reagent is shown to be a mixture of physisorbed KMnO4 and Mn(IV). The influence of the nature of the solvent is discussed.

We have analyzed the influence of the chemical and textural properties of the solid supports as well as the oxidising K2Cr2O7 supported reagent on the oxidation of menthol to menthone—as a reaction test—. The most active K2Cr2O7 supported reagents are obtained with amorphous solid supports with large surface areas or with microcrystalline solids, with great amounts of oxidising sites titrated by phenothiazine.

A case of cyclopia in the sheep is described with anatomic malformations associated. We suggest the possible causes of the congenital defects.

The liquid phase reduction of different substituted nitrobenzene derivatives with the formic acid-triethylamine system has been carried out by the use of a supported palladium (0,6%) on AlPO4/SIO2 (20:80 weigth) catalyst. The reduction rate of nitrocompounds containing electron-acceptor substituents is much higher than that of electron donor-containing substrates.

The oxidation of benzyl halides by DMSO in presence of barium hydroxide as catalyst in the heterogeneous phase is described. The reaction is optimized. The influence of halide and benzyl halide ring substituent on the yield is discussed. The mechanism for the heterogeneous process is discussed.

Several K 2 Cr 2 O 7 supported reagents on inert solids have been obtained by deposition of K 2 Cr 2 O 7 on different solids.A1PO ,BPO and solid mixtures BPO -A1PO are used as supports. The K 2 Cr 2 O 7 is deposited on solid as large crystals detected by an X-ray diagram in the Cr50 and Cr25 series giving solids with very low surface areas.The number of acid and oxidizing sites is dtermined.Solids supports with small surface areas and large pore diameter give K 2 Cr 2 O 7 supported reagents with higher activity than those obtained from solids with high surface areas and large pores.

A demonstration of circulating primordial germ cells in the stage 14 embryo was carried out. The definition of primordial cells was based upon specific criteria utilized by other workers and developed in this study. Evidence supports a passive transport of these cells to the germinal epithelium.

Preparation d'(alcene-1'yl-2) furannes a partir du furfural et d'(alkyl trimethyl) phosphoniums

Several new supported K2Cr2O7 reagents are used in the oxidation of secondary alcohols. The influence of the number of active sites and the nature of solid support on the yield is discussed. The influence of the structure of alcohol on the yield of ketone is analyzed.

Objetivo. Mostrar nuestra experiencia en la formación en endoscopia terapéutica de la vía biliar en modelo animal. Materiales y métodos. Esta actividad formativa tiene una duración de 13 horas y comienza iniciando al alumno en las diferencias anatómicas de las especies que se emplean, la porcina y la canina, con respecto a la anatomía humana. Las prácticas consisten en habituar al endoscopista a la visión lateral del duodenoscopio; se realizan en un modelo porcino debido a que es más sencillo atravesar el esfínter pilórico, aunque no suele ser muy adecuado para la canulación de la papila duodenal. Tras superar la primera fase se utiliza el modelo canino, que permite adquirir las habilidades y destrezas propias de esta técnica. La evaluación de los resultados se realiza mediante una encuesta anónima. Resultados. El 76% de los alumnos confirma que ha avanzado mucho con este entrenamiento, un 18% regular y un 6% poco. El 75% considera que, tras realizar esta actividad de formación, se encontraría capacitado para llevar a cabo la técnica en su hospital. El 94% de los alumnos recomendaría esta actividad a sus compañeros. Conclusiones. El empleo del modelo animal en la formación en colangiopancreatografía retrógada endoscópica (CPRE) permite la adquisición de habilidades básicas necesarias para la práctica, ya que posibilita la repetición de las maniobras y la tutela continuada. Consideramos que con esta metodología mixta se podría acortar la curva de aprendizaje de la CPRE y disminuiría la iatrogenia en las primeras fases.

The presence of annulate lamellae in the germ cells of the chick embryo, in stage 9 of Hamburger/Hamilton (1951), as well as in gonadal germ cells of male chick embryos which had been incubated for 81/2 days, both in normal and experimental conditions, suggests that these formations may be associated with some specific function in the development of this cell line.

Before the appearance of the morphological primordium of the nervous dissociated, reaggregate selectively "in vitro" and reach high levels of neural differentiation and organization. This property allows the experimental reproduction of the neural differentiation process. Before the appearance of the morphological primordium of the nervous system, its precursory cells carry the necessary information to put in action the basic characteristics of cell differentiation and structural organization, even isolated from the influence of mesoblastic cells.

Summary The primordial germ cells (PGC) of the chick embryo in stage 4 of Hamburger/Hamilton (1951) have cytoplasmic formations similar in shape, texture, aggregation and relations with other cell components to the germinal plasm and “nuage” described in other species. The observation of this material in the earliest period of differentiation of PGC suggest that this substance plays an essential role in the determination of the germinal line in birds. The observation of “nuage” material in the PGC of the chick embryo adds evidence for this formation in germ cells.

Using an interactive software program, Virtual Chemistry Laboratory (VCL), we conducted an educational experiment to assess the software's influence on student understanding of some basic organic chemistry laboratory techniques. First-year engineering students at the Superior Polytechnic School of Cordoba were evaluated: more favorable results were obtained from students who had worked with the VCL when compared to results of students who had not worked with the VCL. We conclude that the use of VCL helps students gain a better understanding of the techniques and basic concepts used in the laboratory work. Use of the program particularly contributes towards improving the progress of those students with the greatest learning difficulties.