0000000000704424
AUTHOR
D. Rizzi
Experience with the ALEPH silicon vertex detector
Abstract The ALEPH experiment [1] at LEP is equipped with a vertex detector [2] using two layers of double-sided silicon strip detectors. These detectors allow a real two-dimensional measurement of charged particle tracks. The present (1991) detector has the inner layer at a radius of 6.5 cm and the outer layer at 11.5 cm. The theta angle coverage is ±33° for the inner layer and ±50° for the outer layer. The inner layer is made out of 9 faces with four silicon detectors each, the outer layer has 15 such faces. We use silicon detectors of 5 × 5 cm 2 and 300 μm thickness. The readout pitch is 100 μm at both sides and using capacitive charge division a resolution in the order of 10 μm can be a…
Heterogeneity of KRAS, NRAS, BRAF and PIK3CA mutations in metastatic colorectal cancer and potential effects on therapy in the CAPRI GOIM trial
Background: Evidence suggests that metastatic colorectal carcinoma (mCRC) has a high level of intratumor heterogeneity. We carried out a quantitative assessment of tumor heterogeneity for KRAS, NRAS, BRAF and PIK3CA mutations, in order to assess potential clinical implications. Patients and methods: Tumor samples (n = 182) from the CAPRI-GOIM trial of first-line cetuximab + FOLFIRI in KRAS exon-2 wild-type mCRC patients were assessed by next-generation sequencing that allows quantitative assessment of mutant genes. Mutant allelic frequency was normalized for the neoplastic cell content and, assuming that somatic mutations usually affect one allele, the Heterogeneity Score (HS) was calculate…
Maternal complications and procedures in pregnancy and at birth and wheezing phenotypes in children
There is increasing interest in the potential influence of fetal and early life conditions on childhood wheezing.To investigate the associations between maternal complications and procedures in pregnancy and at birth and the risk of various wheezing phenotypes in young children.We studied 15,609 children, aged 6-7 yr, enrolled in a population-based study. Standardized questionnaires were completed by the children's mothers.Of the children, 9.5% (1,478) had transient early wheezing, 5.4% (884) had persistent wheezing, and 6.1% (948) had late-onset wheezing. Maternal hypertension or preeclampsia was associated with an increased risk of all three wheezing phenotypes (for transient early wheezi…
Operational experience with a large detector system using silicon strip detectors with double sided readout
Abstract A large system of silicon strip detectors with double sided readout has been successfully commissioned over the course of the last year at the e + e − collider LEP. The readout of this 73 728 channel system is performed with custom designed VLSI charge sensitive amplifier chips (CAMEX64A). An overall point resolution of 12 μm on both sides has been acheived for the complete system. The most important difficulties during the run were beam losses into the detector, and a chemical agent deposited onto the electronics; however, the damage from these sources was understood and brought under control. This and other results of the 1991 data-taking run are described with special emphasis o…