1,987 research outputs found
Comparison Of Viral Trajectories In Aids Studies By Using Nonparametric Mixed-Effects Models
The efficacy of antiretroviral therapies for human immunodeficiency virus (HIV) infection can be assessed by studying the trajectory of the changing viral load with treatment time, but estimation of viral trajectory parameters by using the implicit function form of linear and nonlinear parametric models can be problematic. Using longitudinal viral load data from a clinical study of HIV-infected patients in Taiwan, we described the viral trajectories by applying a nonparametric mixed-effects model. We were then able to compare the efficacies of highly active antiretroviral therapy (HAART) and conventional therapy by using Young and Bowman’s (1995) test
Effects of Salt Concentrations and Nitrogen and Phosphorus Starvations on Neutral Lipid Contents in the Green Microalga Dunaliella tertiolecta
Dunaliella tertiolecta, a halotolerant alga, can accumulate large amounts of neutral lipid, which makes it a potential biodiesel feedstock. In this study, neutral lipids of D. tertiolecta induced by different salinities or N or P starvation were analyzed by thin-layer chromatography (TLC), flow cytometry (FCM), and confocal laser scanning microscopy (CLSM). High salinities or N or P starvation resulted in a decrease in cell growth and chlorophyll contents of D. tertiolecta. Neutral lipid contents increased markedly after 3-7 days of N starvation or at low NaCl concentrations (0.5-2.0 M). N starvation had a more dramatic effect on the neutral lipid contents of D. tertiolecta than P starvation. Four putative ME isozymes in different conditions can be detected by using isozyme electrophoresis. Two alternative acetyl-CoA producers, ACL and ACS genes, were up-regulated under low salinities and N starvation. It was suggested that low salinities and N starvation are considered efficient ways to stimulate lipid accumulation in D. tertiolecta.</p
Characterisation of volatile components of red and sparkling wines from a new wine grape cultivar 'Meili' (Vitis vinifera L.)
'Meili' (Vitis vinifera L.) is a new wine grape cultivar from China. Volatile profiles of red and sparkling wines made from 'Meili' grapes were analysed using stir bar sorptive extraction-gas chromatography-mass spectrometry in this study. Fiftyfive volatile compounds were quantified in both wines, and quantitative differences for most of the volatile compounds between 'Meili' wines were observed. 'Meili' sparkling wine had a greater content of esters, fatty acids and shikimic acid derivatives than 'Meili' red wine, although 'Meili' red wine had higher concentrations of alcohols, terpenoids and C13-norisoprenoids. On the basis of odour activity values, ethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, isoamyl acetate, ethyl 2-methylpropanoate, ethyl 3-methylbutanoate, octanoic acid, isoamyl alcohol, 2-phenyl ethanol, linalool, β-damascenone and β-ionone were considered as important aroma compounds in 'Meili' wines. For these compounds, 'Meili' sparkling wine had higher content of ethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate and isoamyl acetate than 'Meili' red wine, while 'Meili' red wine had higher levels of isoamyl alcohol, 2-phenylethanol, linalool, β-damascenone and β-ionone. The concentration differences of aroma compounds due to the differential vinification procedures suggested the differences in sensory characteristics of the two types of wines. In particular, 'Meili' red wine had more rose aroma than 'Meili' sparkling wine.
N-CycloÂhexyl-2-(2,3-dichloroÂphenÂoxy)acetamide
In the crystal structure of title compound, C14H17Cl2NO2, the cycloÂhexyl ring is in a chair conformation and the molÂecules are connected via N—H⋯O hydrogen bonding into chains
Molecular pentaquark states with open charm and bottom flavors
We study the possibly-existing molecular pentaquark states with open charm
and bottom flavors, {\it i.e.}, the states with the quark contents
and (). We investigate the meson-baryon
interactions through the coupled-channel unitary approach within the local
hidden-gauge formalism, and extract the poles by solving the Bethe-Salpeter
equation in coupled channels. These poles qualify as molecular pentaquark
states, which are dynamically generated from the meson-baryon interactions
through the exchange of vector mesons. We calculate their masses and widths as
well as their couplings to various coupled channels. Our results suggest the
existence of the and
molecular states with isospin as well as the and molecular states with isospin
.Comment: 48 pages, 5 figures, 5 tables, suggestions and comments welcom
- …