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.

Ex Input:
Context: Blood oxygenation level-dependent (BOLD)-weighted and vessel-encoded arterial spin labeling (VE-ASL) MRI provide complementary information and can be used in sequence to gauge hemodynamic contributions to cerebrovascular reactivity. Here, cerebrovascular reactivity is assessed using dual echo VE-ASL MRI to understand how VE labeling preparations influence BOLD and ASL contrast in flow-limited and healthy perfusion territories.', 'Patients (n\u2009=\u200912; age\u2009=\u200955 +/- 14 years; 6F/6M) presenting with ischemic steno-occlusive cerebrovascular disease underwent 3.0T angiographic imaging, T1 -weighted structural, and planning-free dual echo hypercarbic hyperoxic (i.e., carbogen) VE-ASL MRI. Vasculopathy extent, timecourses, and cerebrovascular reactivity (signal change and Z-statistic) for different VE-ASL images were contrasted across flow territories and Bonferroni-corrected P-values reported.', 'BOLD cerebrovascular reactivity (i.e., long-TE VE-ASL) Z-statistics were similarly sensitive to asymmetric disease (P\u2009≤\u20090.002) regardless of labeling scenario. Cerebral blood flow reactivity correlated significantly with BOLD reactivity (Z-statistic). However, BOLD signal changes did not differ significantly between labeling scenarios (P\u2009>\u20090.003) or across territories (P\u2009>\u20090.002), indicating BOLD signal changes in response to carbogen offer low sensitivity to lateralizing disease.
Answer: Dual echo VE-ASL can provide simultaneous cerebral blood flow and qualitative BOLD contrast consistent with lateralizing disease severity in patients with asymmetric steno-occlusive disease. The methodological strengths and limitations of composite BOLD and VE-ASL measurements in the clinic are discussed.

Ex Output:
Do dual echo vessel-encoded ASL for simultaneous BOLD and CBF reactivity assessment in patients with ischemic cerebrovascular disease?


Ex Input:
Context: Bacillus cereus group isolates that produce diarrheal or emetic toxins are frequently isolated from raw milk and, in spore form, can survive pasteurization. Several species within the B. cereus group are closely related and cannot be reliably differentiated by established taxonomical criteria. While B. cereus is traditionally recognized as the principal causative agent of foodborne disease in this group, there is a need to better understand the distribution and expression of different toxin and virulence genes among B. cereus group food isolates to facilitate reliable characterization that allows for assessment of the likelihood of a given isolate to cause a\xa0foodborne disease.', 'We performed whole genome sequencing of 22 B. cereus group dairy isolates, which represented considerable genetic diversity not covered by other isolates characterized to date. Maximum likelihood analysis of these genomes along with 47 reference genomes representing eight validly published species revealed nine phylogenetic clades. Three of these clades were represented by a single species (B. toyonensis -clade V, B. weihenstephanensis - clade VI, B. cytotoxicus - VII), one by two dairy-associated isolates (clade II; representing a putative new species), one by two species (B. mycoides, B. pseudomycoides - clade I) and four by three species (B. cereus, B. thuringiensis, B. anthracis - clades III-a, b, c and IV). Homologues of genes encoding a principal diarrheal enterotoxin (hemolysin BL) were distributed across all, except the B. cytotoxicus clade. Using a lateral flow immunoassay, hemolysin BL was detected in 13 out of 18 isolates that carried hblACD genes. Isolates from clade III-c (which included B. cereus and B. thuringiensis) consistently did not carry hblACD and did not produce hemolysin BL. Isolates from clade IV (B. cereus, B. thuringiensis) consistently carried hblACD and produced hemolysin BL. Compared to others, clade IV was significantly (p\u2009=\u20090.0001) more likely to produce this toxin. Isolates from clade VI (B. weihenstephanensis) carried hblACD homologues, but did not produce hemolysin BL, possibly due to amino acid substitutions in different toxin-encoding genes.
Answer: Our results demonstrate that production of diarrheal enterotoxin hemolysin BL is neither inclusive nor exclusive to B. cereus sensu stricto, and that phylogenetic classification of isolates may be better than taxonomic identification for assessment of B. cereus group isolates risk for causing a diarrheal foodborne disease.

Ex Output:
Is production of hemolysin BL by Bacillus cereus group isolates of dairy origin associated with whole-genome phylogenetic clade?


Ex Input:
Context: To examine whether hypercapnia in very low birth weight (VLBW) infants during the first 3 days of life is associated with severe intraventricular hemorrhage (IVH).', 'Retrospective cohort study of inborn VLBW infants between January 1999 and May 2004 with arterial access during the first 3 days of life. A multiple logistic regression analysis was used where IVH was dichotomized ((grades 0/1/2) = non-severe; (grades 3/4) = severe). Measures of hypercapnia were entered into the model to ascertain their association with severe IVH.', 'In total, 574 VLBW infants met entry criteria. Worst IVH grade was 0 in 400; 1: 54; 2: 42; 3: 47; and 4: 31 infants. The logistic regression model consisted of the following predictors of severe IVH: gestational age, gender, 1 min Apgar score (dichotomized into two groups: >3 vs < or =3), multifetal gestation, vasopressor use, and maximum PaCO(2).
Answer: In addition to traditional risk factors, it appears maximum PaCO(2) is a dose-dependent predictor of severe IVH during the permissive hypercapnia era.

Ex Output:

Is hypercapnia during the first 3 days of life associated with severe intraventricular hemorrhage in very low birth weight infants?