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: Biotechnological screening processes are performed since more than 8 decades in small scale shaken bioreactors like shake flasks or microtiter plates. One of the major issues of such reactors is the sufficient oxygen supply of suspended microorganisms. Oxygen transfer into the bulk liquid can in general be increased by introducing suitable baffles at the reactor wall. However, a comprehensive and systematic characterization of baffled shaken bioreactors has never been carried out so far. Baffles often differ in number, size and shape. The exact geometry of baffles in glass lab ware like shake flasks is very difficult to reproduce from piece to piece due to the hard to control flow behavior of molten glass during manufacturing. Thus, reproducibility of the maximum oxygen transfer capacity in such baffled shake flasks is hardly given.', 'As a first step to systematically elucidate the general effect of different baffle geometries on shaken bioreactor performance, the maximum oxygen transfer capacity (OTRmax) in baffled 48-well microtiter plates as shaken model reactor was characterized. This type of bioreactor made of plastic material was chosen, as the exact geometry of the baffles can be fabricated by highly reproducible laser cutting. As a result, thirty different geometries were investigated regarding their maximum oxygen transfer capacity (OTRmax) and liquid distribution during shaking. The relative perimeter of the cross-section area as new fundamental geometric key parameter is introduced. An empirical correlation for the OTRmax as function of the relative perimeter, shaking frequency and filling volume is derived. For the first time, this correlation allows a systematic description of the maximum oxygen transfer capacity in baffled microtiter plates.
Answer: Calculated and experimentally determined OTRmax values agree within ± 30% accuracy. Furthermore, undesired out-of-phase operating conditions can be identified by using the relative perimeter as key parameter. Finally, an optimum well geometry characterized by an increased perimeter of 10% compared to the unbaffled round geometry is identified. This study may also assist to comprehensively describe and optimize the baffles of shake flasks in future.

Ex Output:
Is cross-section perimeter a suitable parameter to describe the effects of different baffle geometries in shaken microtiter plates?


Ex Input:
Context: To determine whether the number and location of positive surgical margins (PSMs) in radical prostatectomy (RP) surgical specimens affect biochemical recurrence (BCR) rates.', 'The locations of PSMs were recorded for 1308 consecutive men who underwent RP between October 2000 and December 2006. BCR was defined as three consecutive prostate-specific antigen (PSA) level rises with the peak level >or=0.15 ng/mL. Multivariate regression analyses were used to identify preoperative predictors of PSMs and BCR. The estimated 5-year risk of BCR was calculated using the Kaplan-Meier method.', 'In all, 128 (9.8%) men had one or more PSMs. The mean body mass index, mean preoperative serum PSA level, the distributions of clinical stage and biopsy Gleason scores, and the presence or absence of biopsy perineural invasion were significantly different between men with or with no PSMs. In multivariate analysis, baseline serum PSA level, Gleason score and perineural invasion were independent preoperative predictors of PSMs. The 5-year actuarial BCR rates were dependent on the site of the PSM (P = 0.035) and not the number of PSMs (P = 0.18). The rank order of estimated 5-year BCR rates according to the site of PSMs were base > anterior > posterolateral > apex approximately posterior.
Answer: About half of the men with PSMs in the RP surgical specimen in our prospective series did not develop BCR. The risk of BCR was dependent on the site and not the number of PSMs. Adjuvant therapy should be considered in cases with anterior and basilar PSMs due to the very high risk of BCR.

Ex Output:
Does site of positive surgical margins influence biochemical recurrence after radical prostatectomy?


Ex Input:
Context: Esophageal squamous cell carcinoma (ESCC) is an important cause of cancer-related death worldwide. To improve prognoses in patients with ESCC, we evaluated the potential of transforming growth factor-beta-induced protein (TGFBI), which is overexpressed in ESCC, as a therapeutic candidate.', 'We examined the clinical significance of TBFBI in 102 ESCC samples using real-time RT-PCR. Immunohistochemical studies were conducted to examine the localization of TGFBI. Knockdown of TGFBI in cocultured fibroblasts was performed to determine the roles of TGFBI in migration and invasion.', 'The level of TGFBI in ESCC tissues was higher than that in normal tissues. The high TGFBI expression group (n = 16) had higher TGFB1 expression and more frequent hematogenous recurrence than the low-expression group (n = 86). High TGFBI expression was an independent prognostic factor in patients with ESCC. TGFBI was mainly localized in stromal cells of ESCC. Moreover, suppression of TGFBI in fibroblasts inhibited the migration and invasion capacity of TE8 ESCC cells.
Answer: High TGFBI expression in ESCC tissues could be a powerful biomarker of poor prognosis and hematogenous recurrence. TGFBI in stromal cells might be a promising molecular target for ESCC treatment.

Ex Output:

Is tGFBI Expression in Cancer Stromal Cells Associated with Poor Prognosis and Hematogenous Recurrence in Esophageal Squamous Cell Carcinoma?