1,548 research outputs found
Extension of apparent devolatilization kinetics from thermally thin to thermally thick particles in zero dimensions for woody biomass
Devolatilization kinetics of woody biomass at short residence times and high heating rates and peak temperatures
Regulated Expression of Human Histocompatibility Leukocyte Antigen (HLA)-DO During Antigen-dependent and Antigen-independent Phases of B Cell Development
Human histocompatibility leukocyte antigen (HLA)-DO, a lysosomal resident major histocompatibility complex class II molecule expressed in B cells, has previously been shown to be a negative regulator of HLA-DM peptide loading function. We analyze the expression of DO in human peripheral blood, lymph node, tonsil, and bone marrow to determine if DO expression is modulated in the physiological setting. B cells, but not monocytes or monocyte-derived dendritic cells, are observed to express this protein. Preclearing experiments demonstrate that ∼50% of HLA-DM is bound to DO in peripheral blood B cells. HLA-DM and HLA-DR expression is demonstrated early in B cell development, beginning at the pro-B stage in adult human bone marrow. In contrast, DO expression is initiated only after B cell development is complete. In all situations, there is a striking correlation between intracellular DO expression and cell surface class II–associated invariant chain peptide expression, which suggests that DO substantially inhibits DM function in primary human B cells. We report that the expression of DO is markedly downmodulated in human germinal center B cells. Modulation of DO expression may provide a mechanism to regulate peptide loading activity and antigen presentation by B cells during the development of humoral immune responses
The Ursinus Weekly, May 6, 1971
Dennis Stoner sings in memorial concert • Dr. Loren C. Eiseley speaks at Myrin Library dedication • The new Ursinus chapter initiates 21 students into Omicron Delta Epsilon • Economics seminar meets; Discusses Federal Reserve; Claims financial trend up • Ullman and Malinauskas chosen as new YM-YWCA presidents • Editorial: It\u27s up to us! • Student Life Committee meets, proposes several changes • Student Activities Committee regulates entire campus life • \u2771 Ruby progresses; Finances look good • Nuclear power plant planned; Limerick reactor site disputed • WRUC elects officers; R. Teel general manager • Theater critic: A look at Broadway • Rough week for tennis squad; Championship matches begin Sat. • Bears win two more; MACs start Friday • Bears lacrosse stay No. 1; Girls take 7 out of 12 • New baseball team looks very promising • Varsity golf improving; Peter Allen shoots parhttps://digitalcommons.ursinus.edu/weekly/1145/thumbnail.jp
The Ursinus Weekly, May 6, 1971
Dennis Stoner sings in memorial concert • Dr. Loren C. Eiseley speaks at Myrin Library dedication • The new Ursinus chapter initiates 21 students into Omicron Delta Epsilon • Economics seminar meets; Discusses Federal Reserve; Claims financial trend up • Ullman and Malinauskas chosen as new YM-YWCA presidents • Editorial: It\u27s up to us! • Student Life Committee meets, proposes several changes • Student Activities Committee regulates entire campus life • \u2771 Ruby progresses; Finances look good • Nuclear power plant planned; Limerick reactor site disputed • WRUC elects officers; R. Teel general manager • Theater critic: A look at Broadway • Rough week for tennis squad; Championship matches begin Sat. • Bears win two more; MACs start Friday • Bears lacrosse stay No. 1; Girls take 7 out of 12 • New baseball team looks very promising • Varsity golf improving; Peter Allen shoots parhttps://digitalcommons.ursinus.edu/weekly/1145/thumbnail.jp
Combining visible near-infrared spectroscopy and water vapor sorption for soil specific surface area estimation
Abstract The soil specific surface area (SSA) is a fundamental property governing a range of soil processes relevant to engineering, environmental, and agricultural applications. A method for SSA determination based on a combination of visible near‐infrared spectroscopy (vis‐NIRS) and vapor sorption isotherm measurements was proposed. Two models for water vapor sorption isotherms (WSIs) were used: the Tuller–Or (TO) and the Guggenheim–Anderson–de Boer (GAB) model. They were parameterized with sorption isotherm measurements and applied for SSA estimation for a wide range of soils (N = 270) from 27 countries. The generated vis‐NIRS models were compared with models where the SSA was determined with the ethylene glycol monoethyl ether (EGME) method. Different regression techniques were tested and included partial least squares (PLS), support vector machines (SVM), and artificial neural networks (ANN). The effect of dataset subdivision based on EGME values on model performance was also tested. Successful calibration models for SSATO and SSAGAB were generated and were nearly identical to that of SSAEGME. The performance of models was dependent on the range and variation in SSA values. However, the comparison using selected validation samples indicated no significant differences in the estimated SSATO, SSAGAB, and SSAEGME, with an average standardized RMSE (SRMSE = RMSE/range) of 0.07, 0.06 and 0.07, respectively. Small differences among the regression techniques were found, yet SVM performed best. The results of this study indicate that the combination of vis‐NIRS with the WSI as a reference technique for vis‐NIRS models provides SSA estimations akin to the EGME method
A Scientific Basis for the Development of the Next Generation of Biomass Burners
The kinetics derived from the classical engineering study are used to simulate the devolatilization and char burn-out phases in the CFD model. Likewise, the study on morphology development will be used to estimate suitable sub-routines, e.g. effective drag coeffcients. The full-scale campaign is used to evaluate the results of the generic CFD models. As the qualitative trends can be reproduced, the CFD models can be used to extend the experimental matrix and facilitate process optimization
Mouse CD94/NKG2A Is a Natural Killer Cell Receptor for the Nonclassical Major Histocompatibility Complex (MHC) Class I Molecule Qa-1b
Natural killer (NK) cells preferentially lyse targets that express reduced levels of major histocompatibility complex (MHC) class I proteins. To date, the only known mouse NK receptors for MHC class I belong to the Ly49 family of C-type lectin homodimers. Here, we report the cloning of mouse NKG2A, and demonstrate it forms an additional and distinct class I receptor, a CD94/NKG2A heterodimer. Using soluble tetramers of the nonclassical class I molecule Qa-1b, we provide direct evidence that CD94/NKG2A recognizes Qa-1b. We further demonstrate that NK recognition of Qa-1b results in the inhibition of target cell lysis. Inhibition appears to depend on the presence of Qdm, a Qa-1b-binding peptide derived from the signal sequences of some classical class I molecules. Mouse NKG2A maps adjacent to CD94 in the heart of the NK complex on mouse chromosome six, one of a small cluster of NKG2-like genes. Our findings suggest that mouse NK cells, like their human counterparts, use multiple mechanisms to survey class I expression on target cells
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