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981.
Soenens Bart; Vansteenkiste Maarten; Lens Willy; Luyckx Koen; Goossens Luc; Beyers Wim; Ryan Richard M. 《Canadian Metallurgical Quarterly》2007,43(3):633
In current research on parenting, 2 ways of conceptualizing perceived parental autonomy support can be distinguished. Parental autonomy support can be defined in terms of promotion of independence (PI) or in terms of promotion of volitional functioning (PVF). This study aimed to establish the empirical distinctiveness of both conceptualizations and to examine their relative contribution to the prediction of adolescents' adjustment. The authors conducted 3 studies, 2 which sampled late adolescents (N = 396, mean age = 18.70 years, 79% female; and N = 495, mean age = 19.30 years, 74% female, respectively) and 1 which sampled middle adolescents (N = 153, mean age = 15.12 years, 70% female). Factor analyses pointed to the distinction between perceived PVF and PI. Structural equation modeling (SEM) indicated that whereas perceived PVF uniquely predicted adjustment ( ps .05). SEM also demonstrated that adolescents' self-determined functioning significantly mediates the relationship between perceived parental PVF and adjustment ( ps 相似文献
982.
Edouard Dantoing Nicolas Piton Mathieu Salaün Luc Thiberville Florian Guisier 《International journal of molecular sciences》2021,22(12)
Anti-PD1/PD-L1 immunotherapy has emerged as a standard of care for stage III-IV non-small cell lung cancer (NSCLC) over the past decade. Patient selection is usually based on PD-L1 expression by tumor cells and/or tumor mutational burden. However, mutations in oncogenic drivers such as EGFR, ALK, BRAF, or MET modify the immune tumor microenvironment and may promote anti-PD1/PD-L1 resistance. In this review, we discuss the molecular mechanisms associated with these mutations, which shape the immune tumor microenvironment and may impede anti-PD1/PD-L1 efficacy. We provide an overview of the current clinical data on anti-PD1/PD-L1 efficacy in NSCLC with oncogenic driver mutation. 相似文献
983.
A Lucía JF de las Heras M Pérez JC Elvira A Carvajal AJ Alvarez JL Chicharro 《Canadian Metallurgical Quarterly》1999,115(1):158-164
Trehalose is a saccharide that possesses no reducing group and so has possible use in parenteral nutrition, especially because it can be stored with amino acids without undergoing the Maillard reaction. To evaluate this possibility, a series of experiments were conducted. The activity of trehalase, an enzyme that metabolizes trehalose to glucose, was measured in rabbit serum and kidney. Conversion of trehalose to glucose and excretion of trehalose in the urine were measured in rabbits administered 10% trehalose intravenously. The effects on nutritional indices as indicators of its use as an energy source were also measured in rabbits infused with 8.23 g.kg-1.d-1 (4. 12 g.kg-1 on d 1) of trehalose for 5 d. Trehalase activity resembled maltase activity, both being high in the renal cortex (2.04 +/- 0.71 and 2.93 +/- 0.26 micromol.g-1.min-1, respectively), weak in the medulla, and undetectable in the serum. Serum glucose and insulin concentrations were increased significantly by trehalose infusion. Significant elevations were observed in serum glucose but not insulin levels by maltose infusion. On the other hand, urinary excretion of trehalose (1.1 +/- 2.1% of dose) was significantly lower than that of maltose (10.1 +/- 4.9% of dose). Similar effects of trehalose and maltose infusions as seen in normal rabbits occurred in rabbits with alloxan diabetes (urinary excretion rate, 3. 8 +/- 3.0% of the infused trehalose dose and 35.6 +/- 9.7% of the infused maltose dose). Nitrogen balance was positive in the trehalose- and glucose-infused normal rabbits with significant difference from the control group infused with saline, suggesting that trehalose was used as an energy source. These results suggest that trehalose has the potential for use as a saccharide source for parenteral nutrition. 相似文献
984.
985.
When a new editorial team takes over responsibility for the important task of overseeing the production of a journal, it is critical, for both readers and those interested in publishing their scholarly work in the journal, that they clearly present their vision for the direction of the journal. Such a statement provides an opportunity for the editors to illustrate their plans for interpreting the journal's mandate in a manner that ensures continuity with previous volumes of the journal while also emphasizing areas of the mandate that may not have received the attention they deserve. This editorial is designed with these purposes in mind. In the following paragraphs, we will provide information on the structure and scope of the journal for the next four years, as well as practical information on how authors should interpret the mandate of the journal and submit their work to the journal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
In this article we discuss recent work on coarse-graining methods for microscopic stochastic lattice systems. We emphasize
the numerical analysis of the schemes, focusing on error quantification as well as on the construction of improved algorithms
capable of operating in wider parameter regimes. We also discuss adaptive coarse-graining schemes which have the capacity
of automatically adjusting during the simulation if substantial deviations are detected in a suitable error indicator. The
methods employed in the development and the analysis of the algorithms rely on a combination of statistical mechanics methods
(renormalization and cluster expansions), statistical tools (reconstruction and importance sampling) and PDE-inspired analysis
(a posteriori estimates). We also discuss the connections and extensions of our work on lattice systems to the coarse-graining of polymers. 相似文献
987.
Several publications (e.g., Smil, Reynolds) have shown the links between civilisation and the efficiency of energy options. As a general rule, human progress was supported by more and more efficient energy options. One indicator of this efficiency is the energy payback, the ratio of energy produced to energy invested. From the earliest use of wood to the massive use of oil in the 1970s, energy payback ratios (EPRs) have improved significantly. 相似文献
988.
Simultaneous Object Recognition and Segmentation from Single or Multiple Model Views 总被引:3,自引:0,他引:3
Vittorio Ferrari Tinne Tuytelaars Luc Van Gool 《International Journal of Computer Vision》2006,67(2):159-188
We present a novel Object Recognition approach based on affine invariant regions. It actively counters the problems related
to the limited repeatability of the region detectors, and the difficulty of matching, in the presence of large amounts of
background clutter and particularly challenging viewing conditions. After producing an initial set of matches, the method
gradually explores the surrounding image areas, recursively constructing more and more matching regions, increasingly farther
from the initial ones. This process covers the object with matches, and simultaneously separates the correct matches from
the wrong ones. Hence, recognition and segmentation are achieved at the same time. The approach includes a mechanism for capturing
the relationships between multiple model views and exploiting these for integrating the contributions of the views at recognition
time. This is based on an efficient algorithm for partitioning a set of region matches into groups lying on smooth surfaces.
Integration is achieved by measuring the consistency of configurations of groups arising from different model views. Experimental
results demonstrate the stronger power of the approach in dealing with extensive clutter, dominant occlusion, and large scale
and viewpoint changes. Non-rigid deformations are explicitly taken into account, and the approximative contours of the object
are produced. All presented techniques can extend any view-point invariant feature extractor.
This research was supported by EC project VIBES, the Fund for Scientific Research Flanders, and the IST Network of Excellence
PASCAL. 相似文献
989.
The concept of a valveless acoustic micropump was investigated. Two-dimensional, time-varying, axisymmetric, incompressible
viscous flows through a planar diffuser-nozzle element were analyzed for applications in valveless acoustic micropumps. The
diffuser divergence half-angles (θ), and the maximum pressure amplitudes (P) were independently varied. The inflow was periodic and the excitation frequency (f) was varied over the range 10 kHz ≤ f ≤ 30 kHz. The net time-averaged volume flux and the rectification capability of the diffuser were found as functions of
θ, f, and P. The phase difference between pressure and velocity waveforms, the life time and the size of large scale flow recirculation
regions inside the microdiffuser, and energy losses were found to be strongly frequency dependent. 相似文献
990.
Condition Based Maintenance (CBM) is based on the assessment of equipment state which is obtained by measuring some indicators. When there is uncertainty concerning the state of the equipment, the measurements gathered are called imperfect. In this case the equipment aging and degradation process is assumed to follow a Markov process and is modeled by a Hidden Markov Model (HMM). This article describes a general procedure that can be used to estimate the parameters of the HMM. It is based on the Expectation-Maximization (EM) algorithm. The procedure deals with independent as well as correlated maintenance observations. The latter are most common in CBM applications. Simulated examples are presented. 相似文献