Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: Brassica napus (AACC) is self-compatible, although its ancestor species Brassica rapa (AA) and Brassica oleracea (CC) are self-incompatible. Most B.napus accessions have dominant self-compatibility (SC) resulting from an insertion of 3.6 kb in the promoter region of BnSCR-1 on the A genome, while recessive SC in B.napus has rarely been observed. Expression and cloning of SRK and SCR genes and genetic analysis were carried out to dissect bases of recessive SC in B.napus.', 'Eleven accessions were screened to identify stable recessive SC and had the S genotype BnS-7 on the A genome and BnS-6 on the C genome similarly to BrS-29 and BoS-15, respectively. In eight SC accessions, BnSCR-7 and BnSCR-6 were nearly undetectable and harbored no structural mutations in the promoters, while SRK genes were expressed at normal levels and contained intact CDS, with the exception of BnSRK-7 in line C32. SRK and SCR genes were expressed normally but their CDSs had no mutations in three SC accessions. In self-incompatible S-1300 and 11 F1 hybrids, SRK genes and BnSCR-1300 transcripts were present at high levels, while expression of the BnSCR-7 and BnSCR-6 were absent. Plants of S genotype S1300S1300 were completely SI, while SI phenotypes of SBnS-7SBnS-7 and S1300SBnS-7 plants were segregated in BC1 and F2 populations.
Answer: The recessive SC in eight accessions is caused by the loss of function of BnSCR-7 and BnSCR-6 in pollen. Translational repression contributes to the recessive SC in three accessions, whose SRK and SCR genes were expressed normally and had identical CDSs to BrS-29 or BoS-15. SI in 11 F1 hybrids relies on the expression of BnSCR-1300 rather than SRK genes. Other factor(s) independent of the S locus are involved in recessive SC. Therefore, diverse causes underlie recessive SC in B. napus, yielding insight into these complex mechanisms.
Do gene expression and genetic analysis reveal diverse causes of recessive self-compatibility in Brassica napus L?

Context: Natriuretic peptide (NP) levels are routinely employed as useful diagnostic and prognostic tools in the evaluation of patients with heart failure (HF). As hospitalization is the major consumer of healthcare resources, the prognostic power of admission NPs with regard to the duration of hospitalization deserves further investigation.', 'We assessed retrospectively the association between NP values sampled shortly following unplanned admission and the duration of hospitalization in 2978 patients admitted to a cardiology department. Duration of hospitalization (hours) and survival were determined by interrogation of the electronic medical records system. Associations with peptide levels were estimated using regression models and receiver operating characteristic (ROC) analysis. The results demonstrate a significant positive relationship between NP levels and the duration of hospitalization, after adjusting for age (P < 0.001). The median duration of hospitalization for the lowest BNP and NT-proBNP quintiles were 80 and 97 h, respectively, vs. 224.5 and 236 h for the highest quintiles. Using cut-off levels of 115 pmol/L for BNP and 390 pmol/L for NT-proBNP, the peptides have a positive predictive value of 78% and 85% for a stay >4 days. During follow-up, NP levels were strongly predictive of all-cause mortality.
Answer: The results quantify the strong relationship between NP levels taken following an unplanned admission to a cardiology department and the duration of hospitalization. This information permits improved identification of a patient population likely to require a prolonged hospital stay and consume more healthcare resources. Such patients may require a more aggressive diagnostic, treatment, and management strategy.
Do natriuretic peptide levels taken following unplanned admission to a cardiology department predict the duration of hospitalization?

Context: In vitro biomechanical study using a programmable testing apparatus that replicated physiologic flexion/extension cervical spine motion and loading mechanics.', 'To determine the influence of anterior plating on multilevel cervical strut-graft mechanics in vitro.', 'The addition of anterior instrumentation does not prevent construct failure in multilevel cervical corpectomy.', 'Six fresh human cadaveric cervical spines (C2-T1) were tested in the four following sequential conditions: harvested, C4-C6 corpectomy, strut-grafted, and strut-grafted with an anterior cervical plate. A force-sensing strut-graft was used to measure compression/tension, flexion/extension and lateral bending moments, and axial torsion. Parameters of stiffness, vertebral motion, and strut-graft loads were compared to determine differences between the four spine conditions.', 'Application of the anterior plate significantly increased the global stiffness (P < 0.01) and decreased the local motion (P < or = 0.01) of the instrumented levels (C3-C7). Flexion of the strut-grafted spine loaded the strut-graft, whereas extension unloaded the strut-graft. With the anterior plate, flexion of the plated spine unloaded the strut-graft. Extension significantly loaded the strut-graft more than similar degrees of flexion in the strut-grafted condition (P = 0.01). Strut-graft loading end limits of 225 N were reached with a mean 7.5 degrees extension in the plated spines.
Answer: Anterior multilevel cervical plating effectively increases stiffness and decreases local cervical motion after corpectomy. However, anterior cervical plating also reverses graft loads and excessively loads the graft in extension, which may promote pistoning and failure of multilevel constructs.
Does anterior cervical plating reverse load transfer through multilevel strut-grafts?