Autotract: Automatic cleaning and tracking of fibers

We propose a new tool named Autotract to automate fiber tracking in diffusion tensor imaging (DTI). Autotract uses prior knowledge from a source DTI and a set of corresponding fiber bundles to extract new fibers for a target DTI. Autotract starts by aligning both DTIs and uses the source fibers as seed points to initialize a tractography algorithm. We enforce similarity between the propagated source fibers and automatically traced fibers by computing metrics such as fiber length and fiber distance between the bundles. By analyzing these metrics, individual fiber tracts can be pruned. As a result, we show that both bundles have similar characteristics. Additionally, we compare the automatically traced fibers against bundles previously generated and validated in the target DTI by an expert. This work is motivated by medical applications in which known bundles of fiber tracts in the human brain need to be analyzed for multiple datasets

Estimation of Canadian manure and fertilizer nitrogen application rates for crops at the soil polygon level using the CANB v2.0 model

Non-Peer ReviewedIn response to national environmental and climate change modeling projects such as agri-environmental indicators, greenhouse gases, carbon sequestration and policy scenarios, fertilizer N and manure nitrogen N application rates were estimated for individual crops at the Soil Landscapes of Canada (SLC) polygon scale (1:1 million). This database provides an estimate of the actual amount of N applied per crop and per hectare, based on provincial fertilization recommendations, manure production levels of each type of livestock and reported amounts of fertilizer sold. The database is being incorporated into ongoing programs related to Kyoto accounting of greenhouse gas emissions, environmental performance and policy formulation at Agriculture and Agri-Food Canada. A standardized Canadian Agricultural Nitrogen Budget (CANB v2.0) model was developed to calculate the agri-environmental indicators Residual Soil Nitrogen (RSN) and Indicator of Risk of Water Contamination by Nitrogen (IROWC-N). CANB is a national-level model that operates on 3500 SLC polygons using generalized soil, landscape, climate, and Census of Agriculture socioeconomic data. It is designed to provide a regional update on the soil N balance for each of the census years of 1981, 1986, 1991, 1996, 2001 and into the future. The database and model have the capability to calculate a number of different components of the nutrient balance, including the inputs of fertilizer N, manure N, biological N and atmospheric N and N the removals of N in the harvested proportion of the crop and via nitrogenous gas emissions. This paper describes the procedures to estimate fertilizer N and manure N inputs for each crop within each polygon. It includes: (i) the compilation of soil-specific N application rates from provincial extension guidelines, (ii) the calculation of total manure N production from animal numbers and excretion rates, (iii) the calculation of available manure N after storage and handling losses, and (iv) the recommended and adjusted nitrogen application rates. Adjustments were made to account for the amount of inorganic N in the manure applied to the various crops. The adjusted nitrogen rate data was also reconciled with the provincial fertilizer sales data

Revisión sobre métodos de preparación, mecanismos y aplicaciones de péptidos antioxidantes en aceites

Natural antioxidants, especially those used in edible oil, are safer compared to chemically synthesized antioxidants. Therefore, research on natural antioxidants has become prevelant. Antioxidant peptides derived from food protein can effectively prevent oil oxidation. Protein hydrolyzation is widely applied for the production of antioxidant peptides in industry, and bioinformatics is employed nowadays to generate the desired peptide sequence. Furthermore, the mechanism of antioxidant peptides in the oil system is still controversial, which limits the further development of antioxidant peptides as food antioxidants. This review introduces the preparation method of antioxidant peptides and their mechanisms as well as applications in the oil. It will help to comprehensively understand the function of antioxidant peptides and promote their development in the oil field.Los antioxidantes naturales, especialmente utilizados en aceites comestibles, son más seguros en comparación con los antioxidantes sintetizados químicamente. Por lo tanto, la investigación sobre antioxidantes naturales se convierte en un punto de interés. Los péptidos antioxidantes derivados de las proteínas alimentarias pueden prevenir eficazmente la oxidación del aceite. La hidrolización de proteínas se usa ampliamente en la industria para la producción de péptidos antioxidantes y la bioinformática se emplea hoy en día para generar la secuencia de péptidos deseada. Además, el mecanismo de los péptidos antioxidantes en el sistema oleoso sigue siendo controvertido, lo que limita el desarrollo posterior de péptidos antioxidantes como antioxidantes alimentarios. Esta revisión presenta el método de preparación de péptidos antioxidantes y su mecanismo, así como las aplicaciones en aceite, lo que ayudará a comprender de manera integral la función de los péptidos antioxidantes y promoverá su desarrollo en el campo petrolero

An Algorithm for Matching Perspective Views of 3-D Object by Using Composite Circuits

National Science Foundation / MCS 82-06926Ope

Drying of the Qaidam basin and its controlling factors deduced from core SG-1

Abstract HKT-ISTP 2013 B

Caffeine Suppresses GABA Receptor-Mediated Current in Rat Primary Sensory Neurons Via Inhibition of Intracellular Phosphodiesterase

In acutely isolated rat primary sensory neurons, the effects of caffeine on GABA receptormediated current (IGABA) were investigated using a whole-cell patch clamp technique. We found that applications of GABA (10-1000 µM) induced inward currents in a concentration-dependent manner; the currents manifested obvious desensitization. Pretreatment with caffeine (0.01- 100 µM) suppressed IGABA in a noncompetitive manner; caffeine shifted the concentration – response curve for GABA downwards compared to the control. Theophylline showed a similar and stronger inhibitory effect on IGABA. Isolated application of 1 µM diazepam enhanced IGABA, while pretreatment with 10 µM caffeine and 1 µM diazepam suppressed this current. Intracellular application of the protein kinase A inhibitor H-8 dramatically weakened the inhibitory effect of caffeine on IGABA. Because primary afferent depolarization is related to GABAA receptors, our results suggest that caffeine might antagonize presynaptic inhibitory effects of primary afferents, probably via inhibition of intracellular phosphodiesterase.Досліджували впливи кофеїну на струми, опосередковані рецепторами ГАМК (IGABA), в гостроізольованих первинних нейронах щура; використовували методику петчклемп у конфігурації «ціла клітина». Аплікації ГАМК (10–1000 мкМ) викликали струми вхідного напрямку, амплітуда котрих була залежною від концентрації; струми демонстрували яскраво виражену десенситизацію. Попередня обробка кофеїном (0.01–100 мкМ) призводила до неконкурентного пригнічення IGABA. Вплив кофеїну зміщував вниз криву концентрація–відповідь для ГАМК порівняно з контролем. Теофілін демонстрував подібні й навіть сильніші гальмівні впливи на IGABA. Ізольована аплікація 1 мкМ діазепаму посилювала IGABA, тоді як попередня обробка 10 мкМ кофеїну перед дією 1 мкМ діазепаму пригнічувала цей струм. Внутрішньоклітинна аплікація H-8 (інгібітору протеїнкінази А) дуже значно послаблювала гальмівний вплив кофеїну на IGABA. Оскільки деполяризація терміналий первинних аферентів опосередковується рецепторами ГАМК, наші результати вказують на те, що кофеїн може протистояти пресинаптичному гальмуванню первинних аферентів. Ефекти кофеїну опосередковуються гальмуванням внутрішньоклітинної фосфодіестерази

Study of the Anti-Proliferative Activity of 5-Substituted 4,7-Dimethoxy-1,3-Benzodioxole Derivatives of SY-1 from Antrodia camphorata on Human COLO 205 Colon Cancer Cells

A set of 10 4,7-dimethoxy-1,3-benzodioxole derivatives based on a lead compound previously discovered by our group, SY-1, which was isolated from Antrodia camphorata, were evaluated for their in vitro inhibitory activity on human colorectal carcinoma cells (COLO 205). Structure-activity relationship studies of the 10 compounds indicated the importance of the chain length of the alkyl group at the 5-position, and the 2-propenyl substituent named “apiole” exhibited the most potent inhibitory activity. In the present study, we demonstrate that the SY-1 analogue “apiole” decreased the proliferation of COLO 205 cells, but not that of normal human colonic epithelial cells (FHC). The G0/G1 cell cycle arrest induced by apiole (75–225 μM) was associated with significantly increased levels of p53, p21 and p27 and decreased levels of cyclin D1. Concerning COLO 205 cell apoptosis, apiole (>150 μM) treatment significantly increased the levels of cleaved caspases 3, 8, 9 and bax/bcl-2 ratio and induced ladder formation in DNA fragmentation assay and sub-G1 peak in flow cytometry analysis. These findings suggest that apiole can suppress COLO 205 cell growth; however, the detailed mechanisms of these processes require further investigation

Electronic Structure and Optical Properties of the Co-doped Anatase TiO2_{2} Studied from First Principles

The Co-doped anatase TiO$_{2}$, a recently discovered room-temperature ferromagnetic insulator, has been studied by the first-principles calculations in the pseudo-potential plane-wave formalism within the local-spin-density approximation (LSDA), supplemented by the full-potential linear augmented plane wave (FP-LAPW) method. Emphasis is placed on the dependence of its electronic structures and linear optical properties on the Co-doping concentration and oxygen vacancy in the system in order to pursue the origin of its ferromagnetism. In the case of substitutional doping of Co for Ti, our calculated results are well consistent with the experimental data, showing that Co is in its low spin state. Also, it is shown that the oxygen vacancy enhances the ferromagnetism and has larger effect on both the electronic structure and optical properties than the Co-doping concentration only.Comment: 12 pages, 4 figure

Leveraging auxiliary data to improve precision in inverse probability-weighted analyses

Purpose: To demonstrate improvements in the precision of inverse probability-weighted estimators by use of auxiliary variables, i.e., determinants of the outcome that are independent of treatment, missingness or selection. Methods: First with simulated data, and then with public data from the National Health and Nutrition Examination Survey (NHANES), we estimated the mean of a continuous outcome using inverse probability weights to account for informative missingness. We assessed gains in precision resulting from the inclusion of auxiliary variables in the model for the weights. We compared the performance of robust and nonparametric bootstrap variance estimators in this setting. Results: We found that the inclusion of auxiliary variables reduced the empirical variance of inverse probability-weighted estimators. However, that reduction was not captured in standard errors computed using the robust variance estimator, which is widely used in weighted analyses due to the non-independence of weighted observations. In contrast, a nonparametric bootstrap estimator properly captured the precision gain. Conclusions: Epidemiologists can leverage auxiliary data to improve the precision of weighted estimators by using bootstrap variance estimation, or a closed-form variance estimator that properly accounts for the estimation of the weights, in place of the standard robust variance estimator