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In northern peatlands, near‐saturated surface conditions promote valuable ecosystem services such as carbon storage and drinking water provision. Peat saturated hydraulic conductivity (Ksat) plays an important role in maintaining wet surface conditions by moderating drainage and evapotranspiration. Peat Ksat can exhibit intense spatial variability in three dimensions and can change rapidly in response to disturbance. The development of skillful predictive equations for peat Ksat and other hydraulic properties, akin to mineral soil pedotransfer functions, remains a subject of ongoing research. We report a meta‐analysis of 2,507 northern peat samples, from which we developed linear models that predict peat Ksat from other variables, including depth, dry bulk density, von Post score (degree of humification), and categorical information such as surface microform type and peatland trophic type (e.g., bog and fen). Peat Ksat decreases strongly with increasing depth, dry bulk density, and humification; and increases along the trophic gradient from bog to fen peat. Dry bulk density and humification are particularly important predictors and increase model skill greatly; our best model, which includes these variables, has a cross‐validated r2 of 0.75 and little bias. A second model that includes humification but omits dry bulk density, intended for rapid field estimations of Ksat, also performs well (cross‐validated r2 = 0.64). Two additional models that omit several predictors perform less well (cross‐validated r2 ∼ 0.5), and exhibit greater bias, but allow Ksat to be estimated from less comprehensive data. Our models allow improved estimation of peat Ksat from simpler, cheaper measurements. Key Points: We report skillful statistical models to estimate saturated hydraulic conductivity in northern peats from simpler measurementsPeat dry bulk density and humification (von Post score) are particularly powerful predictorsOur models represent an improvement over existing pedotransfer functions for peat saturated hydraulic conductivity [ABSTRACT FROM AUTHOR]

Background. Several studies have demonstrated the superior tocolytic effectiveness of nifedipine over ritodrine. Only 1 trial conducted a long-term follow-up of newborns and found no difference in psychosocial and motor functioning. In a randomised, multicentre trial, we compared the tocolytic effectiveness of nifedipine and ritodrine and included a long-term follow-up of the newborns after 2 years of age. Methods. Patients with imminent preterm labour were randomised and received either nifedipine or ritodrine. Side-effects, tocolytic effectiveness and neonatal outcome were studied. Development of the children was studied after the age of 2 years by a parental questionnaire. Results. Ninety-three patients were included. Birth was postponed for an average of 4.3 weeks in the ritodrine group and 5.0 weeks in the nifedipine group (p=0.4). Patients who received ritodrine experienced significantly more side-effects compared to patients who received nifedipine (29 versus 4%, p<0.05). No significant differences were found in either group for average birth weight, Apgar scores after 1 min, neonatal intensive care unit (NICU) admission and neonatal complications. Parental questionnaires after 2 years had a response rate of 70%. Two-thirds of the children had developed normally in both groups. In both groups, only a few children were severely retarded (n=4). No significant differences in development were found between the 2 groups. Conclusions. Both nifedipine and ritodrine proved effective tocolytic drugs, however ritodrine caused significantly more maternal side-effects. Neonatal outcome and long-term development after 2 years of age were not significantly different. We favour nifedipine over ritodrine as a tocolytic drug. [ABSTRACT FROM AUTHOR]

Objective: To trace development of quinacrine sterilization (QS).Methods: Review of published reports.Results: The high prevalence of septic abortion among high parity women in Santiago, Chile, motivated Zipper to find a safe, inexpensive method of non-surgical female sterilization. Various cytotoxic drugs were tried in rats. Because quinacrine was already accepted for intrapleural injection it was chosen for the first clinical trial. A slurry consisting of quinacrine and xylocaine was instilled into the uterine cavity with a transcervical syringe. Reasonable efficacy was noted and a limited scar of the intramural tube demonstrated. However, a side effect of cortical excitation and reports of 3 deaths ended this approach. Zipper and Wheeler hypothesized that the difficulty was due to rapid absorption of quinacrine under pressure and designed a pellet form that dissolves slowly and could be delivered transcervically using a modified IUD inserter. A standard protocol of 252 mg in seven 36 mg pellets placed at the uterine fundus on two occasions a month apart has now been widely used with considerable evidence for safety and efficacy. Indeed, protection is greater than 98% at 2 years of use.Conclusion: QS is ready for widespread use, especially where surgical sterilization is not safely available or when women are poor candidates for surgery or have such a fear of surgery that they will not seek surgical sterilization. [ABSTRACT FROM AUTHOR]