Brain enhancement through cognitive training: A new insight from brain connectome

Owing to the recent advances in neurotechnology and the progress in understanding of brain cognitive functions, improvements of cognitive performance or acceleration of learning process with brain enhancement systems is not out of our reach anymore, on the contrary, it is a tangible target of contemporary research. Although a variety of approaches have been proposed, we will mainly focus on cognitive training interventions, in which learners repeatedly perform cognitive tasks to improve their cognitive abilities. In this review article, we propose that the learning process during the cognitive training can be facilitated by an assistive system monitoring cognitive workloads using electroencephalography (EEG) biomarkers, and the brain connectome approach can provide additional valuable biomarkers for facilitating leaners' learning processes. For the purpose, we will introduce studies on the cognitive training interventions, EEG biomarkers for cognitive workload, and human brain connectome. As cognitive overload and mental fatigue would reduce or even eliminate gains of cognitive training interventions, a real-time monitoring of cognitive workload can facilitate the learning process by flexibly adjusting difficulty levels of the training task. Moreover, cognitive training interventions should have effects on brain sub-networks, not on a single brain region, and graph theoretical network metrics quantifying topological architecture of the brain network can differentiate with respect to individual cognitive states as well as to different individuals' cognitive abilities, suggesting that the connectome is a valuable approach for tracking the learning progress. Although only a few studies have exploited the connectome approach for studying alterations of the brain network induced by cognitive training interventions so far, we believe that it would be a useful technique for capturing improvements of cognitive function

1,3-oxazinan-2-ones from amines and 1,3-diols through dialkyl carbonate chemistry

A one-pot green synthesis of 1,3-oxazinan-2-ones from amines and 1,3-diols in the presence of a dialkyl carbonate and potassium tert-butoxide is described. Four dialkyl carbonates were utilised: dimethyl carbonate, diethyl carbonate, diprop-2-yl carbonate, and tert-butyl methyl carbonate. The more hindered the dialkyl carbonate used, the higher the yield of 1,3-oxazinan-2-one. Four 1,3-diols were reacted having primary-primary, primary-secondary, primary-tertiary, and secondary-tertiary functionalities, with the yield of oxazinanone decreasing with increasing hindrance of the diol. In the case of the diols containing primary and either secondary or tertiary functionality, the substituent(s) were selectively found in the 6-position of the so-formed oxazinanone. The optimized conditions were then employed with different nucleophiles, namely phenylhydrazine, aniline, and n-octylamine. © 2012 Georg Thieme Verlag Stuttgart . New York

Improving Students’ Learning Aspirations Beyond Post-Primary Education: A First Account of Two Non-Formal Education Programmes in Middle-Income Countries

Non-formal education programmes are active in a number of developing countries. These programmes offer vulnerable students an opportunity to pursue their education although they were excluded for various reasons from the formal education systems. This paper examines the impact of two programmes (one in Mauritius, and one in Thailand) on their participants’ aspirations towards learning. We develop a methodology to measure the perception of students regarding their learning experience. More than a third of them, for example, believe that there is no barrier to their education. Most acknowledge the role of their teachers in raising their aspirations towards their educational achievement. When compared to male students, female students seem to value more the role of their education.Non-formal Education, Aspirations, Mauritius, Thailand.

Sulfated titania as additive in Nafion membranes for water electrolysis applications

Hydrogen produced by water splitting is a promising solution for a sustainable economy from renewable energy sources. With this respect, proton exchange membrane (PEM) electrolysis is one of the most suitable technologies, even though low cost, highly active catalysts and durable electrolyte membranes are still needed. Here we demonstrate the successful use of a nano-composite, sulfated titania (S-TiO2)-added Nafion electrolyte coupled with home-made IrRuOx-based anode and commercial Pt cathode in lab-scale water electrolyzers. Superior electrolysis performances were found at 100 °C when comparing the hybrid electrolyte with undoped Nafion. Indeed, current densities of 4 A cm−2 and 3 A cm−2 were found at a terminal voltage of 2 V for the composite and plain membrane, respectively. Ex-situ conductivity measurements, as well as in-operando impedance spectra, were carried out, demonstrating the beneficial effect of the inorganic filler on membrane properties under practical operating conditions. NMR studies (PFG and relaxation time) corroborate the positive role of the nano-additive on the water retention capacity of the membrane, while the dynamic mechanical analysis shows that the hybrid membrane is stiffer and can resist to temperatures higher than undoped Nafion

Radioembolisation with 90Y-microspheres: Dosimetric and radiobiological investigation for multi-cycle treatment

Introduction: Radioembolisation with 90Y-microspheres is a new locoregional treatment of hepatic lesions, usually applied as single cycle. Multi-cycle treatments might be considered as a strategy to improve the risk-benefit balance. With the aim to derive suitable information for patient tailored therapy, available patients' dosimetric data were reviewed according to the linear-quadratic model and converted into biological effective dose (BED) values. Single vs. multi-cycle approaches were compared through radiobiological perspective. Materials and methods: Twenty patients with metastatic lesions underwent radioembolisation. The 90Y-administered activity (AA) was established in order to respect a precautionary limit dose (40 Gy) for the non-tumoral liver (NTL). BED was calculated setting α/β=2.5 Gy (NTL), 10 Gy (tumours); T 1/2,eff=T 1/2,phys=64.2 h; T 1/2,rep=2.5 h (NTL), 1.5 h (tumours). The BED to NTL was considered as a constraint for multi-cycle approach. The AA for two cycles and the percent variations of AA, tumour dose, BED were estimated. Results: In one-cycle, for a prescribed BED to NTL of 64 Gy (NTL dose = 40 Gy), AA was 1.7 (0.9-3.2) GBq, tumour dose was 130 (65-235) Gy, and tumour BED was 170 (75-360) Gy. Considering two cycles, â\u88¼15% increase was found for AA and dose to NTL, with unvaried BED for NTL. Tumour dose increase was 20 (10-35) Gy; tumour BED increase was 10 (3-11) Gy. In different protocols allowing 80 Gy to NTL, the BED sparing estimated was â\u88¼50 Gy (two cycles) and 65 Gy (three cycles). Conclusions: From a radiobiological perspective, multi-cycle treatments would allow administering higher activities with increased tumour irradiation and preserved radiation effects on NTL. Trials comparing single vs. multiple cycles are suggested. © 2008 Springer-Verlag

The role of dosimetry in the high activity 90Y-ibritumomab tiuxetan regimens: Two cases of abnormal biodistribution

Radioimmunotherapy (RIT) with a commercially available brand of yttrium-90 (90Y)-ibritumomab-tiuxetan at the prescribed activity of 14.8 MBq/kg (0.4 mCi/kg) represents a complementary approach in the treatment of resistant/refractory B-cell non-Hodgkin's lymphoma. A trial based on higher activities is ongoing in our institute. In this paper, we report atypical pharmacokinetics and liver uptake in 2 patients. Before RIT, all patients underwent dosimetry with 111In-ibritumomab-tiuxetan. Imaging data were analyzed to obtain predicted absorbed doses to nontarget organs. Therapy was administered only if a 20-Gy-limit dose to normal organs (except red marrow) was guaranteed. Both patients we describe showed abnormal liver uptake, increasing for 6 days post injection. In patient 1, there was atypical biodistribution in whole-blood images at 16 hours, with a prevalent high liver uptake (45% at 20 hours). Injected activity (IA%) was above 40% at 26 hours in the liver and lower than 60% in the total body. In patient 2, early images showed regular biodistribution. Subsequent images showed progressive increase of liver uptake (above 25% of percent injected activity at 25 hours). Liver-absorbed doses of 51 and 53 Gy, respectively, would have resulted with the administration of the prescribed 56 MBq/kg. Following these dosimetric results, both patients did not receive the planned therapy. These findings support the recommendation to include dosimetry in high-dose RIT. © 2009 Copyright 2009, Mary Ann Liebert, Inc

Peptide receptor radionuclide therapy with 90Y-DOTATOC in recurrent meningioma

Purpose: Meningiomas are generally benign and in most cases surgery is curative. However, for high-grade histotypes or partially resected tumours, recurrence is fairly common. External beam radiation therapy (EBRT) is usually given in such cases but is not always effective. We assessed peptide receptor radionuclide therapy (PRRT) using 90Y-DOTATOC in a group of patients with meningioma recurring after standard treatments in all of whom somatostatin receptors were strongly expressed on meningioma cell surfaces. Methods: Twenty-nine patients with scintigraphically proven somatostatin subtype 2 receptor-positive meningiomas were enrolled: 14 had benign (grade I), 9 had atypical (grade II) and 6 had malignant (grade III) disease. Patients received intravenous 90Y-DOTATOC for 2-6 cycles for a cumulative dose in the range of 5-15 GBq. Clinical and neuroradiological evaluations were performed at baseline, during and after PRRT. Results: The treatment was well tolerated in all patients. MRI 3 months after treatment completion showed disease stabilization in 19 of 29 patients (66%) and progressive disease in the remaining 10 (34%). Better results were obtained in patients with grade I meningioma than in those with grade II-III, with median time to progression (from beginning PRRT) of 61 months in the low-grade group and 13 months in the high-grade group. Conclusion: PRRT with 90Y-DOTATOC can interfere with the growth of meningiomas. The adjuvant role of this treatment, soon after surgery, especially in atypical and malignant histotypes, deserves further investigation. © 2009 Springer-Verlag