64 research outputs found
Neural-network analysis of the vibrational spectra of N-acetyl L-alanyl N '-methyl amide conformational states
Neural-network analysis of the vibrational spectra of N-acetyl L-alanyl N'-methyl amide conformational states
Density-functional theory (DFT) calculations utilizing the Becke 3LYP hybrid functional have been carried out for N-acetyl L-alanine N′-methylamide and examined with respect to the effect of water on the structure, the vibrational frequencies, vibrational absorption (VA), vibrational circular dichroism (VCD), Raman spectra, and Raman optical activity (ROA) intensities. The large changes due to hydration in the structures, and the relative stability of the conformer, reflected in the VA, VCD, Raman spectra, and ROA spectra observed experimentally, are reproduced by the DFT calculations. A neural network has been constructed for reproducing the inverse scattering data (we infer the structural coordinates from spectroscopic data) that the DFT method could produce. The purpose of the network has also been to generate the large set of conformational states associated with each set of spectroscopic data for a given conformer of the molecule by interpolation. Finally the neural network performances are used to monitor a sensitivity analysis of the importance of secondary structures and the influence of the solvent. The neural network is shown to be good in distinguishing the different conformers of the small alanine peptide, especially in the gas phase.Peer reviewe
Med pædagogen på tidsrejse
Hvad skal der til for at gøre børn nysgerrige på lokalhistorien og give dem mod på at høre historier fra fortiden? Hvordan skabes god kulturformidling for børn i alderen 3-6 år? Hvordan kan pædagogiske dagtilbud og museer sammen skabe en ramme, som optimerer børns møde med kulturhistorie? Det kan du læse mere om her.
Artiklen giver et bud på metoder til inddragelse af kulturhistorie i det pædagogiske arbejde, hvor metoderne er afprøvet i et samarbejde mellem pædagoger og museumsformidlere. Pædagogernes ekspertise om børnegrupper og børns udvikling sammen med museumsformidlernes viden om kulturhistorie forenes i et kulturhistorisk tilbud målrettet børn i alderen 3-6 år
Chronic hepatitis C in Swedish subjects receiving opiate substitution therapy-Factors associated with advanced fibrosis.
Background: Opiate substitution therapy (OST) reduces the risk of death from directly drug-related causes in heroin users, allowing other chronic health problems to emerge. People who inject drugs (PWID) are exposed to hepatitis C virus (HCV), with an associated risk of chronic liver disease. We investigated HCV prevalence and liver-related morbidity in a cohort of OST recipients, and analyzed factors associated with significant hepatic fibrosis. Methods: All patients registered on 1 April 2008 in 4 clinics providing OST in the 3 largest cities in Sweden were eligible for inclusion. HCV viremic subjects were evaluated for fibrosis stage by liver biopsy, transient elastometry (TE), and/or a biochemical fibrosis index (Göteborg University Cirrhosis Index; GUCI). Factors associated with severity of fibrosis were determined by logistic regression analysis. Results: Out of 524 eligible patients, 277 consented to enrolment. Two hundred and thirty-six subjects (88%) were anti-HCV-positive, and 162 of these were viremic (69%). Significant liver fibrosis (defined as Ishak stages F3-F6, TE value ≥ 8.85 kPa, or GUCI > 0.33) was found in 69 out of 103 (67%) tested viremic patients, and was associated with alcohol intake (p = 0.03), higher body mass index (BMI; p = 0.04), and the presence of anti-HBc antibodies (indicating exposure to hepatitis B virus (HBV); p = 0.02). Conclusions: Significant liver fibrosis was detected in two-thirds of HCV viremic OST recipients in this cohort, and was associated with alcohol use, high BMI, and exposure to HBV. These findings indicate that the management of HCV and associated risk factors should be emphasized in Swedish OST programs
Simulation of Doxorubicin Delivery via Glucosamine(ethylene glycol) Carrier
This article focuses on the molecular modeling of the release of doxorubicin from capsules composed of glucosamine(ethylene glycol) oligomers. Doxorubicin forms micelle structures with glucosamine(ethylene glycol), and the drug release mechanism can be studied through the modeling of oligomeric bond breaking under acidic, neutral, or basic conditions. Under these conditions, the activation energies were calculated to be 145.51, 135.78, and 287.60 kcal/mol, respectively, at the B3LYP/6-31G//PM3 level. Based on these values, doxorubicin can be released into acidic and neutral solutions but not into basic solution. Ethylene glycol chain length in glucosamine(ethylene glycol) also effects drug release. As the length of ethylene glycol increases, the amount of drug released increases under acidic conditions, but decreases under neutral and basic conditions. When the drug is released from glucosamine(ethylene glycol) oligomers, the drug molecule and glucosamine(ethylene glycol) molecules form a micelle structure. Studies found that, as the length of the ethylene glycol chains increases, the micelle structure is more easily formed. The ethylene glycol group can deliver doxorubicin to cancer cells in micelle form
Caught in the Clash amid Customs and Market: A Case of the Poor and Marginalized Rural Population’s Access to Land in Zambia
The paper is a case study analyzing the effects of the Zambian Lands Act of 1995. The problem area centers on the question as to why the market-based land reform of 1995 in Zambia has not, despite its purpose, improved the access to land for the poor and marginalized rural population. The ability to acquire land titles in Zambia highly depends on (i) access to knowledge, (ii) legal access, (iii) access through social identity, and (iv) access to authority. The findings of this paper reveal a reality in which mostly Zambian elites, chiefs, and foreign investors benefit from the prevalent power structures gaining exclusive control over land. Additionally, problems such as complicated and costly bureaucratic procedures as well as civil status, traditional hierarchies, and corruptive behavior weaken the poor and marginalized rural population’s access to land. The paper concludes that the Zambian market-based land reform in 1995 has not benefited the poor and marginalized rural population’s access to land, but has intensified inequalities
Chronic hepatitis C in Swedish subjects receiving opiate substitution therapy—Factors associated with advanced fibrosis
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