Spin transport in graphene nanostructures

Graphene is an interesting material for spintronics, showing long spin relaxation lengths even at room temperature. For future spintronic devices it is important to understand the behavior of the spins and the limitations for spin transport in structures where the dimensions are smaller than the spin relaxation length. However, the study of spin injection and transport in graphene nanostructures is highly unexplored. Here we study the spin injection and relaxation in nanostructured graphene with dimensions smaller than the spin relaxation length. For graphene nanoislands, where the edge length to area ratio is much higher than for standard devices, we show that enhanced spin-flip processes at the edges do not seem to play a major role in the spin relaxation. On the other hand, contact induced spin relaxation has a much more dramatic effect for these low dimensional structures. By studying the nonlocal spin transport through a graphene quantum dot we observe that the obtained values for spin relaxation are dominated by the connecting graphene islands and not by the quantum dot itself. Using a simple model we argue that future nonlocal Hanle precession measurements can obtain a more significant value for the spin relaxation time for the quantum dot by using high spin polarization contacts in combination with low tunneling rates

Strategi UMKM Untuk Bangkit dan Naik Kelas Dengan Akuntansi di Era Pandemi Covid-19

The purpose of this study is to find out the UMKM Strategy so that they can rise in the Covid-19 pandemic era with accounting and how UMKM can advance to class with accounting in the Covid-19 Pandemic Era. The sample in this study was 86 (eighty six) UMKM in Jambi City. The data in this study are primary and secondary data. The analytical method used is descriptive qualitative. The results of the study show that accounting can be a strategy for UMKM to rise in the era of the covid-19 pandemic through the presentation of financial statements in accordance with accounting standards in Indonesia and accounting can make UMKM advance through the presentation of financial statements in accordance with accounting standards in Indonesian.Tujuan penelitian ini adalah untuk mengetahui Startegi UMKM agar bisa bangkit di era pandemi Covid-19 dengan akuntansi dan bagaimana UMKM bisa naik kelas dengan akuntansi di Era Pandemi Covid-19. Sampel pada penelitian ini adalah 86 (delapan puluh enam) UMKM di Kota Jambi.  Data dalam penelitian adalah data primer dan sekunder. Metode analisis yang digunakan adalah Deskriptif kualitatif. Hasil penelitian menunjukkan bahwa akuntansi dapat menjadi strategi untuk UMKM bangkit di era pandemi covid – 19 melalui penyajian laporan keuangan sesuai dengan standar akuntansi di Indonesia serta akuntansi dapat membuat UMKM naik kelas melalui penyajian laporan keuangan sesuai dengan standar akuntansi di Indonesia

Spin transport in high quality suspended graphene devices

We measure spin transport in high mobility suspended graphene (\mu ~ 10^5 cm^2/Vs), obtaining a (spin) diffusion coefficient of 0.1 m^2/s and giving a lower bound on the spin relaxation time (\tau_s ~ 150 ps) and spin relaxation length (\lambda_s=4.7 \mu m) for intrinsic graphene. We develop a theoretical model considering the different graphene regions of our devices that explains our experimental data.Comment: 22 pages, 6 figures; Nano Letters, Article ASAP (2012) (http://pubs.acs.org/doi/abs/10.1021/nl301050a

Telenovelas, telespectadores e representações do amor

A proposta deste artigo é analisar representações do amor em algumas telenovelas brasileiras exibidas recentemente pela Rede Globo, bem como o posicionamento e interlocução estabelecida entre telespectadores e tais narrativas ficcionais O objetivo é delinear um universo simbólico sobre o valor do amor, construído na interlocução entre telenovela e vida social, entre ficção e realidade. Os sentidos configurados nessa relação são atuantes na permanente atualização do ethos contemporâneo, ou seja, do conjunto de referências que orientam a vida dos sujeitos, dentre as quais o amor ocupa um lugar central

COVID-19 and the support network of the National Pastoral of the Elderly

The objective of this study, carried out by the Center for the Study and Research of Aging at PUC-SP, Brazil, in partnership with Staffordshire University – England, UK, was to analyze the action of volunteers from the National Pastoral of the Elderly, in terms of practical support and loving accompaniment. during the Covid-19 pandemic. The study is cross-sectional, quantitative, with a non-probabilistic sample, and involved 4,114 volunteers, mostly women, through telephone interviews done on a 7 period in May 2020

Acute and sub chronic toxicity study of aqueous extract from the leaves and branches of Campomanesia velutina (Cambess) O. Berg.

Ethnopharmacological relevance: Campomanesia velutina leaves and branches infusions are used in Brazilian folk medicine to treat diarrhea and to ameliorate intestinal cramps, respectively. Aim of the study: Carry out the acute and sub chronic pre-clinical evaluation and thus assess the safety and toxicological potential of the specie. Materials and methods: In vivo toxicity was evaluated by acute and sub chronic toxicity assays conducted according to the guidelines of the Brazilian Agency of National Health Surveillance (Ag?ncia Nacional de Vigil?ncia Sanit?ria ? ANVISA). For acute toxicity evaluation, a single dose of aqueous extracts from the leaves (AEL) and branches (AEB) of Campomanesia velutina were orally administered to mice at doses of 300, 600 and 1200 mg/kg. Then, the animals were observed for 14 days. In the sub chronic study, the extracts were orally administered to mice for 14 days at doses of 300, 600 and 1200 mg/kg. To assess the toxicological effects, animals were closely observed on general behavior, clinical signs of toxicity, body weight, food and water intake. At the end of the experiment, it was performed biochemical and hematological evaluations, as well as histopathological analysis from the following organs: brain, heart, lungs, liver, stomach, small intestine (section) and left kidney. Preliminary phytochemical analysis was performed using thin layer chromatography (TLC) and colorimetric pharmacognostic tests. Results: In oral acute assay, treatment with AEB at the major dose (1200 mg/kg) caused diarrhea, abdominal cramps and tremors in females. These effects were reversed at 4th hour. Normochromic normocytic anemia was observed in males treated with AEL 300 mg/kg and AEB 600 and 1200 mg/kg as well as in females treated with AEB 300 and 1200 mg/kg. The kidney of all treated animals showed moderate inflammation and a few hemorrhagic points. In sub chronic assay, treatment with AEL 600 mg/kg, AEL 1200 mg/kg and AEB 1200 mg/kg caused hyper excitability in females that was not reversed. Treatments also had impact on weight gain and the relative weight of males? brain was increased on group treated with AEL 300 mg/kg, AEB 300 and AEB 1200 mg/kg. Although changes in hematological parameters were not observed, serum creatinine levels were significantly higher in males treated with AEB 300 mg/kg. Besides, the heart of all treated animals showed intense hyperemia. Preliminary phytochemical analysis revealed the presence of flavonoids, tannins and phenolic compounds. Conclusions: Toxicity signs were mainly observed after treatment with AEL and AEB at the two highest tested doses (600 and 1200 mg/kg), suggesting that the extracts are relatively safe at its effective dose (300 mg/kg). However, alterations on hematological and biochemical parameters and on the kidney and heart of the animals were not closely related with the dose, implying caution on its use

Inhibition of macrophage migration inhibitory factor decreases proliferation and cytokine expression in bladder cancer cells

BACKGROUND: The importance of various inflammatory cytokines in maintaining tumor cell growth and viability is well established. Increased expression of the proinflammatory cytokine macrophage migration inhibitory factor (MIF) has previously been associated with various types of adenocarcinoma. METHODS: MIF IHC was used to localize MIF in human bladder tissue. ELISA and Western blot analysis determined the synthesis and secretion of MIF by human bladder transitional cell carcinoma cells. The effects of MIF inhibitors (high molecular weight hyaluronate (HA), anti-MIF antibody or MIF anti-sense) on cell growth and cytokine expression were analyzed. RESULTS: Human bladder cancer cells (HT-1376) secrete detectable amounts of MIF protein. Treatment with HA, anti-MIF antibody and MIF anti-sense reduced HT-1376 cell proliferation, MIF protein secretion, MIF gene expression and secreted inflammatory cytokines. Our evidence suggests MIF interacts with the invariant chain, CD74 and the major cell surface receptor for HA, CD44. CONCLUSIONS: This study is the first to report MIF expression in the human bladder and these findings support a role for MIF in tumor cell proliferation. Since MIF participates in the inflammatory response and bladder cancer is associated with chronic inflammatory conditions, these new findings suggest that neutralizing bladder tumor MIF may serve as a novel therapeutic treatment for bladder carcinoma

Aspergillus as a multi-purpose cell factory: current status and perspectives

Aspergilli have a long history in biotechnology as expression platforms for the production of food ingredients, pharmaceuticals and enzymes. The achievements made during the last years, however, have the potential to revolutionize Aspergillus biotechnology and to assure Aspergillus a dominant place among microbial cell factories. This mini-review will highlight most recent breakthroughs in fundamental and applied Aspergillus research with a focus on new molecular tools, techniques and products. New trends and concepts related to Aspergillus genomics and systems biology will be discussed as well as the challenges that have to be met to integrate omics data with metabolic engineering attempts

Drug-Induced Regulation of Target Expression

Drug perturbations of human cells lead to complex responses upon target binding. One of the known mechanisms is a (positive or negative) feedback loop that adjusts the expression level of the respective target protein. To quantify this mechanism systems-wide in an unbiased way, drug-induced differential expression of drug target mRNA was examined in three cell lines using the Connectivity Map. To overcome various biases in this valuable resource, we have developed a computational normalization and scoring procedure that is applicable to gene expression recording upon heterogeneous drug treatments. In 1290 drug-target relations, corresponding to 466 drugs acting on 167 drug targets studied, 8% of the targets are subject to regulation at the mRNA level. We confirmed systematically that in particular G-protein coupled receptors, when serving as known targets, are regulated upon drug treatment. We further newly identified drug-induced differential regulation of Lanosterol 14-alpha demethylase, Endoplasmin, DNA topoisomerase 2-alpha and Calmodulin 1. The feedback regulation in these and other targets is likely to be relevant for the success or failure of the molecular intervention