Tallgrass prairie butterfly surveys in recent decades in four states in the USA indicate numerous declines of prairie-specialist butterflies including Speyeria idalia, Oarisma poweshiek, Atrytone arogos, Hesperia dacotae, and H. ottoe in fire-managed preserves, including large high-quality ones. These results replicate previous findings, indicating that upon initiation of conservation action, both cessation of prior management and inception of new management affect specialists negatively and that butterfly declines can be as great on reserves as nonreserves. Results at Wisconsin sites with species-specific management protocols, including permanent non-fire refugia, were more favorable for the specialists (S. idalia, Lycaeides melissa samuelis) the protocols were specifically designed to benefit. Butterfly declines after preservation will likely continue unless the conservation approach changes to include consideration of individual species' required resources and management tolerances. The ecosystem approach assumes that habitat specialists are co-evolved with processes such as fires assumed to maintain those ecosystems. Data presented here indicate that tallgrass prairie specialist butterflies are not co-evolved with current fire regimes. An alternate perspective views ecological processes as resetting vegetation to current climate and landscape conditions. Over geologic time, relict vegetation associations persist as outliers until an event resets them. In modern times, human disturbances (especially soil-exposing ones) can reset sites to favour the more generalist species (plants and butterflies) found in the prevailing, human-degraded landscape.
Single-chain human recombinant factor VII produced by transfected baby hamster kidney cells was purified to homogeneity in the presence of benzamidine. The amidolytic activity of single-chain recombinant factor VII with a peptidylnitroanilide substrate, methoxycarbonyl-D-cyclohexanylglycyl-L-arginine-p-nitroanilide, was less than 1% of that obtained with factor VIIa. Purified single-chain recombinant factor VII spontaneously activated in the absence of inhibitor. The activation reaction was enhanced by at least 2 orders of magnitude in the presence of a positively charged surface, provided either as an anion-exchange matrix or as poly(D-lysine). The progress curve for factor VIIa generation was sigmoidal. Benzamidine inhibits recombinant factor VIIa activity and factor VII activation with identical inhibition constants (Ki) of 11 mM. In contrast, benzamidine inhibition of bovine factor Xa and bovine factor IIa was observed at Ki values equal to 0.3 and 0.5 mM, respectively. Bovine factors Xa and IIa are known activators of factor VII and the most likely contaminants of our recombinant factor VII preparations. Single-chain recombinant factor VII purified from cells cultured in the absence of bovine serum activated at the same rate as factor VII from cells cultured in the presence of bovine serum. This also excluded the possibility that the activation reaction was caused by contaminating bovine proteases. On the basis of these observations, we propose that factor VII is autoactivated in vitro in the presence of a positively charged surface.
Background: Distal pancreatectomy (DP) is increasingly done by laparoscopy but data from routine practise are scarce. We describe practise in a national cohort. Methods: Data from the Norwegian Patient Register of all patients undergoing DP from 2012 to 2016. National resection rates were analysed. Short-term outcomes include length of stay, reoperation, readmissions and 90-day mortality. Risk is reported as odds ratio (OR) with 95% confidence interval (c.i.).Results: Of 554 procedures, 327 (59%) were laparoscopic. Median age was 66 years (iqr 55-72) and 52% were women. Resection rates increased during the period for all DP (from 1.76 to 2.39 per 100.000/ yr), and significantly for laparoscopic DP (adjusted R-square 0.858; P = 0.015). Elderly patients had more resection (r 2 = 0.11; P = 0.019). Splenectomy (n = 427; 77%) was less likely with laparoscopy (laparoscopy 72% vs open 84%, respectively; OR 0.64, 95% c.i. 0.42-0.97; P = 0.035). Multivisceral resections occurred more often in open DP (5.3% vs 1.2% for laparoscopy, OR 4.51, 1.44-14.2; P = 0.008). Reoperation occurred in 34 (6%), readmission in 109 (20%), and mortality in 8 (1.4%).Hospital stay was shorter for laparoscopic DP. Conclusion:Use of DP increases in the population, particularly in the elderly, with use of laparoscopic access and an association with a reduced hospital stay.
BackgroundThe quality of data collected in survey research is usually indicated by the response rate; the representativeness of the sample, and; the rate of completed questions (item-response). In attempting to improve a generally declining response rate in surveys considerable efforts are being made through follow-up mailings and various types of incentives. This study examines effects of including a scratch lottery ticket in the invitation letter to a survey.MethodQuestionnaires concerning oral health were mailed to a random sample of 2,400 adults. A systematically selected half of the sample (1,200 adults) received a questionnaire including a scratch lottery ticket. One reminder without the incentive was sent.ResultsThe incentive increased the response rate and improved representativeness by reaching more respondents with lower education. Furthermore, it reduced item nonresponse. The initial incentive had no effect on the propensity to respond after the reminder.ConclusionWhen attempting to improve survey data, three issues become important: response rate, representativeness, and item-response. This study shows that including a scratch lottery ticket in the invitation letter performs well on all the three.
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