Conformational study and reassessment of the vibrational assignments for Norspermidine

The present study presents and discusses the conformational preferences of Norspermidine (NSpd). The effects of varying the dielectric constant on the conformational preferences are discussed, with a view to infer which conformation will correspond to the most stable in the pure condensed liquid phase. Within the same context, a set of NSpd-NH3 molecular adducts were simulated in order to determine the relevance of intermolecular hydrogen bonding on the overall stability and relative positioning of the respective vibrational frequencies. The calculations presently performed allowed a reassessment of the vibrational assignments for NSpd. A full assignment of the NSpd vibrational spectra is presented, with special emphasis being given to the vibrational modes that proved to be most affected by hydrogen bonding. The various inconsistencies of a prior study found in the literature were identified and rectified

Precipitation reaction in alpha-Cu-Al-Ag alloys

The Ag-rich precipitates formation reaction in the Cu-9.22%at. Al-4.66%at. Ag, Cu-9.31%at. Al-5.83%at. Ag and Cu-9.37%at. Al-7.08%at. Ag alloys was studied using microhardness change measurements with temperature and time, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray diffractometry (XRD). The results indicated that the Ag-rich phase formation is an interface controlled process with a zero-order mechanism, due to the amount of unsolved Ag that makes the precipitation reaction rate independent of Ag concentration.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)UNIFESP Departamento de Ciências Exatas e da TerraUNESP Instituto de Química Departamento de Físico-QuímicaUNIFESP, Depto. de Ciências Exatas e da TerraSciEL

Comparative effectiveness of prostate cancer screening between the ages of 55 and 69 years followed by active surveillance

BACKGROUND: Because of the recent grade C draft recommendation by the US Preventive Services Task Force (USPSTF) for prostate cancer screening between the ages of 55 and 69 years, there is a need to determine whether this could be cost-effective in a US population setting. METHODS: This study used a microsimulation model of screening and active surveillance (AS), based on data from the European Randomized Study of Screening for Prostate Cancer and the Surveillance, Epidemiology, and End Results Program, for the natural history of prostate cancer and Johns Hopkins AS cohort data to inform the probabilities of referral to treatment during AS. A cohort of 10 million men, based on US life tables, was simulated. The lifetime costs and effects of screening between the ages of 55 and 69 years with different screening frequencies and AS protocols were projected, and their cost-effectiveness was determined. RESULTS: Quadrennial screening between the ages of 55 and 69 years (55, 59, 63, and 67 years) with AS for men with low-risk cancers (ie, those with a Gleason score of 6 or lower) and yearly biopsies or triennial biopsies resulted in an incremental cost per quality-adjusted life-year (QALY) of $51,918 or$69,380, respectively. Most policies in which screening was followed by immediate treatment were dominated. In most sensitivity analyses, this study found a policy with which the cost per QALY remained below $100,000. CONCLUSIONS: Prostate-specific antigen–based prostate cancer screening in the United States between the ages of 55 and 69 years, as recommended by the USPSTF, may be cost-effective at a$100,000 threshold but only with a quadrennial screening frequency and with AS offered to all low-risk men. Cancer 2018;124:507-13

Carcass Characteristics Of Purebred And Crossbred Nellore Females Fed Solely Pasture

This research aimed to compare carcasses of purebred and crossbred Nellore females reared uniquely on pasture (Brachiaria decumbens and Brachiaria brizantha cv. Marandu). Breeds assessed consisted of purebred Nellore (16) and Nellore x Santa Gertrudis crossbred (16), being 32 ± 1.5 months old. All animals were slaughtered as they reached 450 kg. Crossbred females showed higher slaughter, hot and cold carcass weights and longer lengths (P < 0.05). Conversely, purebred animals attained greater carcass yields (P < 0.05). Nonetheless, crossbred females had higher primal cut weights and plate/ flank percentage (P < 0.05). Also, non-carcass components as kidneys, liver, kidney-pelvic-heart fat showed higher weights for crossbred females (P < 0.05). Thus, regarding beef cattle reared and finished exclusively on grazing areas, crossbred females (Nellore x Santa Gertrudis) may be the most profitable ones for cattle raisers, since they produce heavier slaughtering carcasses. Notwithstanding, they might be interesting for meat industry, for yielding more in prime cuts than purebreds, even if raised at the same conditions and slaughtered at same age.3764213422

Harms and benefits of prostate cancer screening and active surveillance

Prostate cancer is the second most commonly diagnosed cancer and the 5th cause of cancer death worldwide. The PSA-test consists of a simple blood test which gives the value of PSA in the blood. An elevated PSA value indicates a high probability of presence of cancer, though it could also be due to unrelated causes. While prostate cancer screening may save lives, it also causes harm, since many screen-detected men are overdiagnosed and overtreated. In this thesis I use a microsimulation model (MISCAN) adapted to prostate cancer to explore multiple avenues to make PSA-based screening worthwhile and effective. I find that prostate cancer screening should be focused on younger age groups, Active Surveillance should become the primary treatment option for low-risk men, and that personalized screening strategies should be adopted to minimize the harms of screening

Environmental heterogeneity caused by anthropogenic disturbance drives forest structure and dynamics in Brazilian Atlantic Forest

We evaluated how tree community floristic composition, forest structure and dynamics varied over a period of 13 years across a topographic gradient of ravines created by anthropic disturbance in Brazilian Atlantic Forest. The study area is located within a fragment of Atlantic Forest (21° 09' S, 44° 54' W), in Minas Gerais state, Brazil. This work was based on data of tree diameter at 1.3 m from the soil, collected in four inventories. Each individual was recorded as being in one of three stratified topographic classes: hilltop, slope and bottom. We used direct gradient analysis to evaluate floristic compositional changes, phytosociological analysis to evaluate structural variations, and assessed demographic and biomass changes over time through analysis of rates of forest dynamics. The results did not reflect modifications in the patterns of floristic composition and species diversity along the topographic gradient, while differences in forest structural attributes and dynamics may be detected at these smaller spatial scales. Thus, the same species group may employ different strategies against different restrictive environmental factors. Finally, we suggest that floristic composition and species diversity may be less sensitive parameters for post-disturbance responses than forest dynamics and structure

Different proportion of root cutting and shoot pruning influence the growth of citronella plants

Environment concern, sustainable products demand, and natural components conscious are currently global movement factors. Related to the global movement factors, citronella grass (Cymbopogon nardus L.) is being widely used in folk medicine, and has insect repellent activity, fungal and bactericidal action. Its essential oil has high content of citronellal, citronellol, geraniol. The essential oil is mostly extracted from leaves which turns this plant with high commercial demand. However, to obtain the best therapeutic quality and productivity of medicinal plants, which culminates in greater quantity and quality of the active compounds, the proper management of the crop is fundamental, as several factors can interfere during its growth and development. Thus, we analyzed the growth of citronella plants submitted to different levels of shoot and root cuts. Five different proportions of root pruning (0, 25, 50, 75, 100%), after 145 days of seedling planting and four cuttings in the shoots: blunt; a cut at 145 DAP (days after planting) along with the root cut; a cut at 228 DAP; and cuts at 145 and 228 DAP (two cuts). Four harvesting for dry matter accumulation and photoassimilate partition data were performed. The treatment with 100% root cut, but without leaf cut, increased the total dry mass accumulation of the plant in relation to the other treatments, for the last analysis period, demonstrating a recovery. Thus, the application of two leaf cuts or no leaf cutting within the 100% root cut treatment for leaf dry mass accumulation is more effective when compared to the blunt root treatment

Unparticle effects on top quark rare decays

In this work we study the flavor changing neutral current(FCNC) decays of the top quark, $t\to c\gamma$ and $t\to c g$. The Standard Model, predictions for the branching ratios of these decays are about $\sim 5\times 10^{-14}$, and $\sim 1\times 10^{-12}$, respectively. The recent study presented by the ATLAS Collaboration gives a sensitivity on these branching ratios about $\sim 10^{-5}$ at $$ C.L. The parameter space of $\lambda$, $\Lambda$, and $d$ where the branching ratios of $t\to c\gamma$ and $t\to c g$ decays exceed these predictions is obtained

Classical self-forces in a space with a dispiration

We derive the gravitational and electrostatic self-energies of a particle at rest in the background of a cosmic dispiration (topological defect), finding that the particle may experience potential steps, well potentials or potential barriers depending on the nature of the interaction and also on certain properties of the defect. The results may turn out to be useful in cosmology and condensed matter physics.Comment: 5 pages, 4 figures, revtex4 fil