Validity and worth in the science curriculum: learning school science outside the laboratory

It is widely acknowledged that there are problems with school science in many developed countries of the world. Such problems manifest themselves in a progressive decline in pupil enthusiasm for school science across the secondary age range and the fact that fewer students are choosing to study the physical sciences at higher levels and as careers. Responses to these developments have included proposals to reform the curriculum, pedagogy and the nature of pupil discussion in science lessons. We support such changes but argue from a consideration of the aims of science education that secondary school science is too rooted in the science laboratory; substantially greater use needs to be made of out-of-school sites for the teaching of science. Such usage should result in a school science education that is more valid and more motivating and is better at fulfilling defensible aims of school science education. Our contention is that laboratory-based school science teaching needs to be complemented by out-of-school science learning that draws on the actual world (e.g. through fieldtrips), the presented world (e.g. in science centres, botanic gardens, zoos and science museums) and the virtual worlds that are increasingly available through information and communications technologies (ICT)

Lixiviação e volatilização de nitrogênio em um Argissolo cultivado com videira submetida à adubação nitrogenada.

O nitrogênio (N) aplicado na superfície do solo em vinhedos pode ser perdido por volatilização ou lixiviação, sendo uma das possíveis explicações para o baixo aproveitamento de N pelas videiras. O trabalho objetivou avaliar as perdas de N por volatilização e lixiviação do N mineral em solo cultivado com videira submetida à adubação nitrogenada. Foram instalados dois experimentos em um vinhedo de Cabernet Sauvignon, em Rosário do Sul (RS), Brasil. No experimento 1, foram instalados lisímetros no solo que recebeu a aplicação de 0, 40, 80 e 120kg de N ha-1 ano-1 na forma de ureia e, durante o período de agosto a dezembro de 2009, foi coletada a solução do solo para a análise de N mineral. No experimento 2, foram instaladas câmaras coletoras no solo que recebeu, em agosto de 2010, a aplicação de 0, 20, 40, e 80kg de N ha-1 ano-1 na forma de ureia, 40kg de N ha-1 ano-1 de composto orgânico e 40kg de N ha-1 ano-1 de ureia revestida com polímeros, para avaliar a volatilização de N-NH3 do momento da aplicação até 80 horas depois da aplicação. As maiores concentrações de nitrogênio mineral na solução lixiviada foram encontradas nas doses mais elevadas de fertilizante mineral aplicado e ao longo da brotação e florescimento das videiras, o que pode diminuir o aproveitamento do nutriente pelas plantas. Os maiores fluxos e perdas de amônia do solo cultivado com videira para a atmosfera aconteceram nas doses mais elevadas de nitrogênio mineral aplicado, especialmente, depois de 44 horas da sua aplicação sobre a superfície do solo. A aplicação de ureia revestida com polímeros e composto orgânico promoveram as menores perdas de amônia por volatilização, o que pode estimular o aproveitamento de nitrogênio pelas videiras

Measurement of the Spin Structure of the Deuteron in the DIS Region

We present a new measurement of the longitudinal spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron in the range 1 GeV^2 < Q^2 < 100 GeV^2 and 0.004< x <0.7. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarised muon beam and a large polarised 6-LiD target. The results are in agreement with those from previous experiments and improve considerably the statistical accuracy in the region 0.004 < x < 0.03.Comment: 10 pages, 6 figures, subm. to PLB, revised: author list, Fig. 4, details adde

First Measurement of the Transverse Spin Asymmetries of the Deuteron in Semi-Inclusive Deep Inelastic Scattering

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6-LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.Comment: 6 pages, 2 figure

Ruthenium-thymine acetate binding modes: Experimental and theoretical studies

Ruthenium complexes have proved to exhibit antineoplastic activity, related to the interaction of the metal ion with DNA. In this context, synthetic and theoretical studies on ruthenium binding modes of thymine acetate (THAc) have been focused to shed light on the structure-activity relationship. This report deals with the reaction between dihydride ruthenium mer-[Ru(H)2(CO)(PPh3)3], 1 and the thymine acetic acid (THAcOH) selected as model for nucleobase derivatives. The reaction in refluxing toluene between 1 and THAcOH excess, by H2 release affords the double coordinating species k1-(O)THAc-, k2-(O,O)THAc-[Ru(CO)(PPh3)2], 2. The X-ray crystal structure confirms a simultaneous monohapto, dihapto- THAc coordination in a reciprocal facial disposition. Stepwise additions of THAcOH allowed to intercept the monohapto mer-k1(O)THAc-Ru(CO)H(PPh3)3] 3 and dihapto trans(P,P)-k2(O,O)THAc-[Ru(CO)H(PPh3)2] 4 species. Nuclear magnetic resonance (NMR) studies, associated with DFT (Density Function Theory)-calculations energies and analogous reactions with acetic acid, supported the proposed reaction path. As evidenced by the crystal supramolecular hydrogen-binding packing and 1H NMR spectra, metal coordination seems to play a pivotal role in stabilizing the minor [(N=C(OH)] lactim tautomers, which may promote mismatching to DNA nucleobase pairs as a clue for its anticancer activity

Ru-Controlled Thymine Tautomerization Frozen by a k1(O)-, k2(N,O)-Metallacycle: An Experimental and Theoretical Approach

The reaction of mer-(Ru(H)2(CO)(PPh3)3) (1) with one equivalent of thymine acetic acid (THAcH) unexpectedly produces the macrocyclic dimer k1(O), k2(N,O)-(Ru(CO)(PPh3)2THAc)2 (4) and, concomitantly, the doubly coordinated species k1(O), k2(O,O)-(Ru(CO)(PPh3)2THAc) (5). The reaction promptly forms a complicated mixture of Ru-coordinated mononuclear species. With the aim of shedding some light in this context, two plausible reaction paths were proposed by attributing the isolated or spectroscopically intercepted intermediates on the basis of DFT-calculated energetic considerations. The cleavage of the sterically demanding equatorial phosphine in the mer-species releases enough energy to enable self-aggregation, producing the stable, symmetric 14-membered binuclear macrocycle of 4. The k1-acetate iminol (C=N-OH) unit of the mer-tautomer k1(O)-(Ru(CO)(PPh3)2(THAc)) (2) likely exhibits a stronger nucleophilic aptitude than the prevalent N(H)-C(O) amido species, thus accomplishing extra stabilization through concomitant k2(N,O)-thymine heteroleptic side-chelation. Furthermore, both the ESI-Ms and IR simulation spectra validated the related dimeric arrangement in solution, in agreement with the X-ray determination of the structure. The latter showed tautomerization to the iminol form. The 1H NMR spectra in chlorinated solvents of the kinetic mixture showed the simultaneous presence of 4 and the doubly coordinated 5, in rather similar amounts. THAcH added in excess preferentially reacts with 2 or trans-k2(O,O)-(RuH(CO)(PPh3)2THAc) (3) rather than attacking the starting Complex 1, promptly forming the species of 5. The proposed reaction paths were inferred by spectroscopically monitoring the intermediate species, for which the results were strongly dependent on the of conditions the reaction (stoichiometry, solvent polarity, time, and the concentration of the mixture). The selected mechanism proved to be more reliable, due to the final dimeric product stereochemistry

Noninvasive Evaluation of Liver Fibrosis in a Sample of Putative Inactive HBV Carriers in Rome, Italy

Background: Noninvasive methods are useful for investigating patients with chronic HBV infection. The severity of liver disease in inactive HBsAg carriers can be noninvasively assessed by transient elastography (TE) alone or in association with biochemical markers of fibrosis. Objectives: The study evaluates the effectiveness of the TE compared to common fibrosis scores (FSs), APRI, Forns Index, and FIB4, for identifying significant fibrosis in Italian and foreigner HBsAg carriers. To investigate the risk of progression of the liver disease, liver stiffness (LS) and HBV-DNA were monitored over time. Methods: Viral load, biochemical parameters, and LS have been retrospectively evaluated in 125 putative inactive HBV carriers, who visited two outpatient departments (Colleferro Hospital and INMP) from 01/03/2014 to 31/12/2019. Differences in clinical, biochemical, and demographic variables between Italians and foreigners were analyzed. 66 of 125 patients were followed up for 24 months by monitoring liver stiffness and HBV-DNA. Results: Mean overall LS was 5.55 ± 1.92 kPa; 18 (14.4%) patients had a LS ≥7.5 kPa. Mean of APRI, Forns, and FIB4 was 0.29 ± 0.11, 4.15 ± 1.63, and 1.16 ± 0.59, respectively. FS did not differ between the patients with LS &lt;7.5 kPa and those with LS ≥7.5 kPa. Italians displayed a significant lower ALT (0.53 ± 0.18 vs. 0.67 ± 0.33, p &lt; 0.05) and AST (0.59 ± 0.16 vs. 0.70 ± 0.21, p &lt; 0.01) value than foreigners. No differences in LS and HBV-DNA levels were observed. In 66 patients followed up for 24 months, HBV-DNA increased by ≥2000 UI/ml after 12 months in 15 individuals and remained ≥2000 UI/ml after 24 months in 10/15 individuals. 7/10 patients showed LS ≥ 7.5 kPa after 24 months, and 4 of them underwent antiviral therapy for HBV. Patients with HBV-DNA &lt;2000 IU/ml had a significantly lower LS than those with HBV-DNA ≥2000 IU/ml (5.30 ± 1.43 vs. 7.69 ± 1.07, p &lt; 0.0001). Conclusions: Analysis shows lower effectiveness of FS vs. TE in the assessment of putative inactive HBV carriers. Furthermore, using FibroScan® and HBV-DNA can identify "false" inactive carriers

Graves' ophthalmopathy evolution studied by MRI during childhood and adolescence.

The positive outcome of Graves' ophthalmopathy correlated with low TRAb (autoantibodies to thyroid-stimulating hormone receptor) titers at diagnosis and during follow-up and with prepubertal condition at diagnosis

Education for sustainable development: A study in adolescent perception changes towards sustainability following a strategic planning-based intervention-the young persons' plan for the planet program

© 2019 by the authors. In 2016, the United Nations (UN) launched the 17 Sustainable Development Goals (SDGs) as a framework for sustainable development and a sustainable future. However, the global challenge has been to engage, connect, and empower communities, particularly young people, to both understand and deliver the 17 SDGs. In this study, we show the benefit of a strategic planning-based experiential learning tool, the Young Persons' Plan for the Planet (YPPP) Program, to improve the underlying competencies of Australian and Mauritian adolescents in increasing understanding and delivering the SDGs. The study was conducted with 300 middle to senior high school students, in 25 schools throughout Australia and Mauritius, over an 18-month period. The intervention included the development of research, strategic planning, management, STEM (Science Technology, Engineering, Maths) and global competency skills in the students, to enable them to build and deliver regional and national SDG plans. Research methods included pre- and post-intervention testing of the attitudes of these students to sustainable development outcomes and compared these attitudes to subsets of scientists and the Australian national population. Our results, from both qualitative and quantitative evidence, demonstrate significant improvements in these adolescents' appreciation of, and attitudes towards, the SDGs and sustainable outcomes, across a range of key parameters. The results from the 76 students who attended the International Conference in Mauritius in December 2018 demonstrate significant improvements in mean levels of understanding, and attitudes of the students towards the SDGs awareness (+85%), understanding/engagement (+75%), motivation (+57%), and action orientation/empowerment (+66%). These changes were tested across a range of socio-demographic, geographic, and cultural parameters, with consistent results. These findings have significant implications for the challenge of sustainable education and achieving community engagement and action towards the SDGs in Australia and Mauritius, particularly for young people. As the intervention can be replicated and scaled, the findings also highlight the opportunity to extend both the research and this type of experiential learning intervention across both broader geographies and other generation and community segments