1,957 research outputs found
Green tea polyphenol-reduced graphene oxide: derivatisation, reduction efficiency, reduction mechanism and cytotoxicity
This paper reports on the derivatisation, reduction efficiency, reduction mechanism and cytotoxicity of green tea polyphenol-reduced graphene oxide (GTP-RGO). The reduction of graphene oxide (GO) at 90°C using a weight ratio (WR) of GTP/GO=1 resulted in the production of a stable GTP-RGO dispersion in aqueous media, as indicated by the results of ultravioletvisible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and the measurement of zeta potential and electrophoretic mobility. In addition, the results from UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis indicated the comparable reduction ability of GTP relative to the standard reducing agent, hydrazine (N2H4). The removal mechanism of epoxy group from GO via reduction reaction with GTP was investigated by implementing hybrid functional method of Becke-3-parameters-Lee-Yang-Parr (B3LYP)using Gaussian 09 software. The energy and frequency calculations showed that the GO reduction using GTP was more spontaneous and relatively took place faster than the reduction using N2H4, as evidenced by higher entropy change (ΔS) (0.039 kcal/mol·K) and lower Gibbs free energy (ΔG) barrier (58.880 kcal/mol).The cytotoxicities of GO and GTP-RGO samples were evaluated against human colonic fibroblasts cells (CCD-18Co). The GO sample was determined to be toxic even at low concentration (6.25 μg/mL), while the GTP-RGO sample possesses notably low toxicity at the same concentration. The cell culture experiments revealed that the incorporation of GTP led to a decrease in the toxicity of GTP-RGO samples
Prevalence and distribution of endodontic treatments and apical periodontitis in an Italian population sample
This study was undertaken to investigate for the first time the distribution and prevalence of apical periodontitis and its determinants in an Italian population. A total of 312 participants (191 women, 121 men) received free clinical examination and full-mouth digital X-ray. Data regarding the oral health status of the patients were collected such as the reason for the visit and the incidence of lesions. We examined 8101 teeth, 6.59% of which had been submitted to endodontic treatment and 15.02% of which were lower molars. Lower molars were reported missing more frequently, in detail 16.24%. Moreover 3.89% of the lower molars had developed an apical lesion, whereas only 0.08% of the lower incisors. Periapical lesions were present in 0.29% of not endodontically treated teeth, while in endodontically treated teeth lesions were present in 17.04%. Additionally, 15.65% of the endodontically treated teeth showed incongruous (long or short) seals. A prevalence of women (61.21%) over men (38.78%) was reported indicating that women attend to their oral health more. Endodontic treatment success and failure in over- or under-filled teeth was evaluated with success being verified in 97% of appropriately treated teeth; the success rate decreases in inappropriately treated teeth (by 72.73% in over-filled and 77.71% under-filled teeth). The prevalence of teeth with periapical lesions amounted to 1.35%. Finally, endodontically treated teeth with periapical lesions amounted to 17.04%. Successful treatment can be achieved when disease is intercepted at an early stage while prevention still remains better than cur
Stage 1 Registered Report: How responsibility attributions to self and others relate to outcome ownership in group decisions [version 2; peer review: 2 approved]
Responsibility judgements have important consequences in human society. Previous research focused on how someone's responsibility determines the outcome they deserve, for example, whether they are rewarded or punished. Here, we investigate the opposite link: How outcome ownership influences responsibility attributions in a social context. Participants in a group of three perform a majority vote decision-making task between gambles that can lead to a reward or no reward. Only one group member receives the outcome and participants evaluate their and the other players' responsibility for the obtained outcome. Two hypotheses are tested: 1) Whether outcome ownership increases responsibility attributions even when the control over an outcome is similar. 2) Whether people's tendency to attribute higher responsibility for positive vs negative outcomes will be stronger for players who received the outcome. The findings of this study may help reveal how credit attributions can be biased toward particular individuals who receive outcomes as a result of collective work
Sistem Pendidikan Surau : Karakteristik, Isi, dan Literatur Keagamaan
Mosque constitutes eldest education institute at Minangkabau, even before input Islam goes to Minangkabau mosque have available. With its Islamic coming, mosque also experience islamisasi\u27s process, without has to experience changing name. Hereafter mosque gets amends at Minangkabau. With its amends mosque education institute this, transformasi\u27s happening scholarship and culture to Minang\u27s young men. Knowledge that is gotten at this mosque not only theology just, but also knowledge which is needed deep life everyday, as gnostic as custom, self-defence knowledge, politeness, independence etceter
Stage 1 Registered Report: How responsibility attributions to self and others relate to outcome ownership in group decisions [version 1; peer review: 1 approved with reservations]
Responsibility judgements have important consequences in human society. Previous research focused on how someone's responsibility determines the outcome they deserve, for example, whether they are rewarded or punished. Here, we investigate the opposite link: How outcome ownership influences responsibility attributions in a social context. Participants in a group of three perform a majority vote decision-making task between gambles that can lead to a reward or no reward. Only one group member receives the outcome and participants evaluate their and the other players' responsibility for the obtained outcome. Two hypotheses are tested: 1) Whether outcome ownership increases responsibility attributions even when the control over an outcome is similar. 2) Whether people's tendency to attribute higher responsibility for positive vs negative outcomes will be stronger for players who received the outcome. The findings of this study may help reveal how credit attributions can be biased toward particular individuals who receive outcomes as a result of collective work
Self-consistent Green function approach for calculations of electronic structure in transition metals
We present an approach for self-consistent calculations of the many-body
Green function in transition metals. The distinguishing feature of our approach
is the use of the one-site approximation and the self-consistent quasiparticle
wave function basis set, obtained from the solution of the Schrodinger equation
with a nonlocal potential. We analyze several sets of skeleton diagrams as
generating functionals for the Green function self-energy, including GW and
fluctuating exchange sets. Their relative contribution to the electronic
structure in 3d-metals was identified. Calculations for Fe and Ni revealed
stronger energy dependence of the effective interaction and self-energy of the
d-electrons near the Fermi level compared to s and p electron states.
Reasonable agreement with experimental results is obtained
Pengaruh Supervisi Akademik Kepala Sekolah dan Profesionalitas Guru Terhadap Kualitas Pembelajaran
Tujuan dari penelitian ini adalah untuk menguji tiga hipotesis utama, yaitu: a) Apakah terdapat pengaruh supervisi akademik kepala sekolah terhadap kualitas pembelajaran?; b) Apakah terdapat pengaruh profesionalitas guru terhadap kualitas pembelajaran?; c) Apakah terdapat pengaruh bersama-sama antara supervisi akademik kepala sekolah dan profesionalitas guru terhadap kualitas pembelajaran? Penelitian ini dilakukan di Sekolah Dasar Islam Terpadu (SDIT) se-Kabupaten Kuantan Singingi. Berdasarkan permasalahan dan tujuan penelitian yang ingin dicapai, penelitian ini menggunakan metode survei dengan pendekatan ekspost facto. Pendekatan ini dirancang untuk menilai seberapa besar hubungan koefisien antara variabel bebas dan variabel terikat. Penelitian ini melibatkan dua variabel bebas, yaitu supervisi akademik kepala sekolah, dan profesionalitas guru. Variabel terikatnya adalah kualitas pembelajaran. Melibatkan 136 responden sebagai sampel penelitian. Hasil penelitian, setelah dilakukan analisis data menggunakan aplikasi SPSS, menunjukkan beberapa kesimpulan: 1) Terdapat pengaruh yang signifikan dari supervisi akademik kepala sekolah terhadap kualitas pembelajaran di SDIT se-Kabupaten Kuantan Singingi. 2) Hipotesis kedua diterima, mengindikasikan bahwa profesionalitas guru mempengaruhi kualitas pembelajaran di SDIT se-Kabupaten Kuantan Singingi secara signifikan. 3) Terdapat pengaruh yang signifikan secara simultan antara supervisi akademik kepala sekolah dan profesionalitas guru terhadap kualitas pembelajaran, dengan nilai signifikansi sebesar 0.000 < 0.05 dan nilai Fhitung sebesar 40.255 > Ftabel sebesar 3.064. Oleh karena itu, hipotesis ketiga diterima, menunjukkan bahwa supervisi akademik kepala sekolah dan profesionalitas guru secara bersama-sama memengaruhi kualitas pembelajaran di SDIT se-Kabupaten Kuantan Singingi. Berdasarkan Tabel Model Summary, diperoleh nilai R-Square sebesar 0.443. Hal ini mengindikasikan bahwa terdapat hubungan yang "sedang/cukup" sebesar 44,3% antara supervisi akademik kepala sekolah dan profesionalitas guru secara simultan terhadap kualitas pembelajaran di SDIT se-Kabupaten Kuantan Singingi
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