Given a passage, 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 Q]: The purpose of this study is to examine the effect of insurance coverage on stage of presentation, treatment, and survival of head and neck cancer (HNC).', 'A retrospective study was conducted using the Surveillance, Epidemiology, and End Results (SEER) program to identify patients diagnosed with HNC. The primary variable of interest was insurance analyzed as a dichotomous variable: Patients were considered uninsured if they were classified as "uninsured" by SEER, whereas patients were considered insured if they were defined by SEER as "any Medicaid," "insured," or "insured/no specifics." The outcomes of interest were cancer stage at presentation (M0 vs M1), receipt of definitive treatment, and HNC-specific mortality (HNCSM). Multivariable logistic regression modeled the association between insurance status and stage at presentation, as well as between insurance status and receipt of definitive treatment, whereas HNCSM was modeled using Fine and Gray competing risks. Sensitivity logistic regression analysis was used to determine whether observed interactions remained significant by insurance type (privately insured, Medicaid, and uninsured).', 'Patients without medical insurance were more likely to present with metastatic cancer (adjusted odds ratio, 1.60; P < .001), were more likely to not receive definitive treatment (adjusted odds ratio, 1.64; P < .001), and had a higher risk of HNCSM (adjusted hazard ratio, 1.20; P= .002). Sensitivity analyses showed that when results were stratified by insurance type, significant interactions remained for uninsured patients and patients with Medicaid.
[EX A]: Does health Insurance affect Head and Neck Cancer Treatment Patterns and Outcomes?

[EX Q]: Despite much clinical experience, there are few published accounts of the surgical manifestations of HIV/AIDS in children and still fewer guidelines for the best or most appropriate treatment. Our primary objective was to document the incidence of HIV infection in children who presented with a surgical emergency to a major pediatric surgical unit in South Africa. If possible, we aimed to provide a description of the impact of the disease in a surgical pediatric population and to raise awareness of the mode of presentation of HIV to the pediatric surgeon in a developing nation, now that specific antiretroviral therapies are available.', 'This was a prospective observational study of consecutive surgical emergency admissions to the Division of Paediatric Surgery at the University of the Witwatersrand, Johannesburg, South Africa, between April 1 and May 31, 2005. Consent for inclusion in the study was sought in all cases. The clinical profile of children presenting during the study period was recorded. If relevant, permission was sought from the parent/guardian to undertake HIV status testing if this were not already known.', 'Three hundred ninety-one children were admitted as emergency cases during the study period. Thirty-seven (9.5%) of 391 were excluded, because consent could not be obtained, leaving 354 children. Ages ranged between 1 day and 17 years, with a median age of 3 years. The diagnosis in most was trauma/burns (42%) and abdominal emergencies (27%). Infections occurred in 13% of these patients. Human immunodeficiency virus status was already known in 10 (3%) of 354 patients, and only 18 (5%) of 344 children were tested; of these, 10 (55%) were positive. As expected, the predominant surgical presentation of HIV positive children was sepsis. The prevalence of HIV/AIDS in those children not tested is unknown.
[EX A]: Are surgeons failing to recognize children with HIV infection?

[EX Q]: Stomatal guard cells monitor and respond to environmental and endogenous signals such that the stomatal aperture is continually optimised for water use efficiency. A key signalling molecule produced in guard cells in response to plant hormones, light, carbon dioxide and pathogen-derived signals is hydrogen peroxide (H(2)O(2)). The mechanisms by which H(2)O(2) integrates multiple signals via specific signalling pathways leading to stomatal closure is not known.', 'Here, we identify a pathway by which H(2)O(2), derived from endogenous and environmental stimuli, is sensed and transduced to effect stomatal closure. Histidine kinases (HK) are part of two-component signal transduction systems that act to integrate environmental stimuli into a cellular response via a phosphotransfer relay mechanism. There is little known about the function of the HK AHK5 in Arabidopsis thaliana. Here we report that in addition to the predicted cytoplasmic localisation of this protein, AHK5 also appears to co-localise to the plasma membrane. Although AHK5 is expressed at low levels in guard cells, we identify a unique role for AHK5 in stomatal signalling. Arabidopsis mutants lacking AHK5 show reduced stomatal closure in response to H(2)O(2), which is reversed by complementation with the wild type gene. Over-expression of AHK5 results in constitutively less stomatal closure. Abiotic stimuli that generate endogenous H(2)O(2), such as darkness, nitric oxide and the phytohormone ethylene, also show reduced stomatal closure in the ahk5 mutants. However, ABA caused closure, dark adaptation induced H(2)O(2) production and H(2)O(2) induced NO synthesis in mutants. Treatment with the bacterial pathogen associated molecular pattern (PAMP) flagellin, but not elf peptide, also exhibited reduced stomatal closure and H(2)O(2) generation in ahk5 mutants.
[EX A]:
Does the histidine kinase AHK5 integrate endogenous and environmental signals in Arabidopsis guard cells?