Adult tissue maintenance is often dependent on resident stem cells; however, the phenotypic and functional heterogeneity existing within this self-renewing population is poorly understood. Here, we define distinct subsets of undifferentiated spermatogonia (spermatogonial progenitor cells; SPCs) by differential response to hyperactivation of mTORC1, a key growth-promoting pathway. We find that c...

Nickel Aluminum Bronze (NAB) is a material with marine environment applications. Under certain conditions the material can undergo selective phase corrosion (SPC), which involves the removal of particular elements resulting in a loss of material strength. Additional changes in material properties include a change in conductivity and permeability in comparison with the parent material. Transient...

S PC is SPC is discussed with a view to indicating its implications not only to manufacturing and quality but to research and product development as well. In the manufacturing/quality area, the efforts and methods attending full-scale implementation of SPC are briefly reviewed with special reference to the differences inherent in powder making versus manufacturing of parts. SPC charting techniq...

Sphingosylphosphorylcholine (SPC) is a naturally occurring bioactive sphingolipid in blood plasma, metabolizing from the hydrolysis of the membrane sphingolipid. It has been shown to exert multifunctional role in cell physiological regulation either as an intracellular second messenger or as an extracellular agent through G protein coupled receptors (GPCRs). Because of elevated levels of SPC in...

We investigated the performance of the recently developed SPC/L model for liquid water, as a pure liquid, in binary mixtures with DMSO, and as a solvent model in a peptide folding simulation. Additionally, in order to test the compatibility with the GROMOS biomolecular force field, free energies of hydration of a set of representative compounds were computed. The results are compared to those f...

Two independent methods for improving quality are engineering process control (EPC) and statistical process control (SPC). The first method tries to minimize variability by handling process variables so as to keep the outputs of the process on target. While the latter method, SPC does the same basic task of minimizing variability by supervising and eradicating the assignable causes of variation...

I would observe that this is the third time in six months that I have had to refer questions of interpretation of the SPC Regulation to the CJEU. I do so with considerable regret. That this should be necessary demonstrates the dysfunctional state of the SPC system at present. This is primarily due to the poor drafting of the SPC Regulation and to the failure of the European Commission, Council ...

Inflammation has an important function in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH); however, the mediators of this inflammatory response have not been clearly identified. In this study, we have investigated the potential function of two sphingolipids, which occur naturally in plasma and serum, sphingosylphosphorylcholine (SPC) and sphingosine 1-phosphate (S1P), ...

To cite: Fretheim A, Tomic O. BMJ Qual Saf 2015;24: 748–752. INTRODUCTION Time series plots are widely used, across sectors and media, probably because many find them easy to understand. Figure 1 is a time series plot of how the readmission rate in a hospital changed over time (constructed data set). Statistical process control (SPC) and interrupted time series (ITS) designs are two closely rel...