1,502 research outputs found
Probing the two-scale-factor universality hypothesis by exact rotation symmetry-breaking mechanism
We probe the two-scale factor universality hypothesis by evaluating, firstly
explicitly and analytically at the one-loop order, the loop quantum corrections
to the amplitude ratios for O() scalar field theories with
rotation symmetry-breaking in three distinct and independent methods in which
the rotation symmetry-breaking mechanism is treated exactly. We show that the
rotation symmetry-breaking amplitude ratios turn out to be identical in the
three methods and equal to their respective rotation symmetry-breaking ones,
although the amplitudes themselves, in general, depend on the method employed
and on the rotation symmetry-breaking parameter. At the end, we show that all
these results can be generalized, through an inductive process based on a
general theorem emerging from the exact calculation, to any loop level and
physically interpreted based on symmetry ideas.Comment: 17 pages, 3 figure
Il governo tecnocratico della moneta e i crocevia del processo di integrazione europea. Riflessioni alla luce della sentenza Weiss
The well known judgment of the German Constitutional Court in the “Weiss” case has been widely criticized under EU law, mainly because of its being in contrast with a preliminary ruling rendered by the European Court of Justice in 2018. At variance with these criticisms, it is here submitted that such a judgment brings well into focus some institutional ambiguities of the Economic and Monetary Union (EMU); namely, the powers (more and more) exercised by the European Central Bank (ECB) in the field of macroeconomic regulation and control, in spite of (its) not being provided with political legitimacy. Seen in this perspective, the “Karlsruhe” judgment objectively looks as aimed at restoring a more balanced relationship between different institutional EMU actors, in accordance with their different degree of political legitimacy. Finally, both the role so far (i.e., starting from the “whatever it takes”) played from the ECB and the respective roles played by the German Constitutional Court and the German Government in closing this affair are construed as symptoms of the current imbalances of the European integration process
Metformin induces apoptosis and alters cellular responses to oxidative stress in Ht29 colon cancer cells: Preliminary findings
Accumulating evidence suggests that metformin, used as an antidiabetic drug, possesses anti-cancer properties. Metformin reduced the incidence and growth of experimental tumors in vivo. In a randomized clinical trial among nondiabetic patients, metformin treatment significantly decreased the number of aberrant crypt foci compared to the untreated group with a follow-up of 1 month. In our study, HT29 cells were treated with graded concentrations of metformin, 10 mM/25 mM/50 mM for 24/48 h. We performed immunofluorescence experiments by means of confocal microscopy and western blot analysis to evaluate a panel of factors involved in apoptotic/autophagic processes and oxidative stress response. Moreover, HT29 cells treated with metformin were analyzed by a flow cytometry assay to detect the cell apoptotic rate. The results demonstrate that metformin exerts growth inhibitory effects on cultured HT29 cells by increasing both apoptosis and autophagy; moreover, it affects the survival of cultured cells inhibiting the transcriptional activation of Nuclear factor E2-related factor 2 (NRF-2) and nuclear factor-kappa B (NF-\u3baB). The effects of metformin on HT29 cells were dose- and time-dependent. These results are very intriguing since metformin is emerging as a multi-faceted drug: It has a good safety profile and is associated with low cost and might be a promising candidate for the prevention or the treatment of colorectal cancer
Ekstraksi Selulosa dari Serbuk Gergaji Kayu Sengon melalui Proses Delignifikasi Alkali Ultrasonik
Kayu sengon (Albizia chinensis) merupakan salah satu jenis kayu yangmelimpah di Indonesia. Kandungan selulosa pada kayu sengon cukup tinggi sebesar 41,17%. Proses ekstraksi selulosa dari kayu sengon dapat dilakukan melalui proses delignifikasi atau penghilangan kandungan lignin. Umumnya, proses delignifikasi dilakukan dengan larutan alkali pada konsentrasi tinggi, suhu tinggi dan waktu yang lama.Agar konsentrasi alkali yang digunakan rendah dan waktu lebih pendek, proses delignifikasi dapat dilakukan dengan bantuan ultrasonik. Tujuan dari penelitian ini adalah mengetahui pengaruh kondisi operasi (suhu dan waktu) proses delignifikasi dengan ultrasonik terhadap kadar selulosa yang diperoleh. Proses delignifikasi dilakukan denganmencampur serbuk kayu sengon (40 mesh) dengan larutan NaOH (0,3M) dengan perbandingan 1:30 (w/v). Kondisi operasi yang digunakan adalah suhu 30 °C dan 40 °C pada berbagai waktu (10menit hingga 70menit). Setelah proses delignifikasi, produk di bleaching dengan NaOCl hingga warnanya menjadi putih. Analisis yang dilakukan antara lain adalah metode Chesson, X-Ray Diffraction (XRD) dan Scanning Electron Microscopy (SEM). Hasil dari analisa menunjukkan bahwa kristalinitas tertinggi diperoleh sebesar 77,05 % pada 40 °C selama 30 menit dan kadar lignin turun hingga mencapai 0,41%
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