A functional regression analysis of vessel source level measurements from the Enhancing Cetacean Habitat and Observation (ECHO) database.

Measurements of the source levels of 9880 passes of 3188 different large commercial ships from the Enhancing Cetacean Habitat and Observation (ECHO) program database were used to investigate the dependencies of vessel underwater noise emissions on several vessel design parameters and operating conditions. Trends in the dataset were analyzed using functional regression analysis, which is an extension of standard regression analysis and represents a response variable (decidecade band source level) as a continuous function of a predictor variable (frequency). The statistical model was applied to source level data for six vessel categories: cruise ships, container ships, bulk carriers, tankers, tugs, and vehicle carriers. Depending on the frequency band and category, the functional regression model explained approximately 25%-50% of the variance in the ECHO dataset. The two main operational parameters, speed through water and actual draft, were the predictors most strongly correlated with source levels in all of the vessel categories. Vessel size (represented via length overall) was the design parameter with the strongest correlation to underwater radiated noise for three categories of vessels (bulkers, containers, and tankers). Other design parameters that were investigated (engine revolutions per minute, engine power, design speed, and vessel age) had weaker but nonetheless significant correlations with source levels.

Benthic studies adjacent to Sakhalin Island, Russia 2015 III: benthic energy density spatial models in the nearshore gray whale feeding area.

Energy densities of six dominant benthic groups (Actinopterygii, Amphipoda, Bivalvia, Cumacea, Isopoda, and Polychaeta) and total prey energy were modeled for the nearshore western gray whale feeding area, Sakhalin Island, Russia, as part of a multi-disciplinary research program in the summer of 2015. Energy was modeled using generalized additive mixed models (GAMM) with accommodations for zero-inflation (logistic regression and hurdle models) and regression predictions combined with kriging to interpolate energy densities across the nearshore feeding area. Amphipoda energy density was the highest nearshore and in the south whereas Bivalvia energy density was the highest offshore and in the northern portion of the study area. Total energy was the highest in mid-range distances from shore and in the north. Amphipoda energy density was higher than minimum energy estimates defining gray whale feeding habitats (312-442 kJ/m2) in 13% of the nearshore feeding area whereas total prey energy density was higher than the minimum energy requirement in 49% of the habitat. Inverse distance-weighted interpolations of Amphipoda energy provided a broader scale representation of the data whereas kriging estimates were spatially limited but more representative of higher density in the southern portion of the study area. Both methods represented the general trend of higher Amphipoda energy density nearshore but with significant differences that highlight the value of using multiple methods to model patterns in highly complex environments.

Predictors of cesarean section following elective post-dates induction of labor in nullipara with uncomplicated singleton vertex pregnancies.

OBJECTIVE: Although post-dates is among the most common indications for induction of labor, no studies have identified the predictors of cesarean section (C/S) in that population. The high cesarean rate in our institution for this group of women triggered us to assess different induction practices to elicit potential causes. METHODS: We conducted a hospital-based retrospective cohort analysis using chart reviews of all nullipara women with induced labor at the Children's and Women's Health Centre of British Columbia, Vancouver, Canada, during the 2-year period, April 1998 to March 2000. The C/S rate was compared among 3 groups of women who were divided according to their induction method. RESULTS: Three hundred and thirty-nine women meeting the inclusion criteria were induced. Of the 25 women who received oxytocin ideally and the 111 women who did not, 7 (28%) and 53 (48%) were delivered by C/S, (x2=3.228 p=0.07; relative risks 0.59 [95% confidence interval 0.30, 1.13]). A significantly lower C/S rate (x2=21.9, p<0.0005) was found among women induced with prostaglandin (PG) alone (19.4%) compared with those induced with PG and oxytocin, whether oxytocin was given ideally (38.3%) or not ideally (45.4%). Of women who received oxytocin, there was no difference in chorioamnionitis (x2=0.485, p=0.49) between those who had an early membrane rupture (with or pre-oxytocin, 22.4%) and those who had membrane rupture following a period of oxytocin infusion (18.5%). CONCLUSION: The need for oxytocin or less than 2 doses of PG is associated with increased risk of C/S. Whether oxytocin was given according to protocol (ideally) or not, made no difference to the C/S risk in this population.

The prediction of adverse maternal outcomes in preeclampsia.

OBJECTIVES: (1) To evaluate whether clinical variables reflecting the multiorgan dysfunctions of preeclampsia can predict adverse maternal outcomes of preeclampsia; (2) to determine the usefulness of the mean platelet volume (MPV):platelet ratio as a novel measure of platelet consumption in predicting the severity of preeclampsia. METHOD: A retrospective chart review was conducted of cases of preeclampsia seen in 3 tertiary level units from January 2001 to December 2001. Candidate predictors of adverse maternal outcome were gestational age (GA) on admission to hospital, blood pressure, proteinuria, urine output, uric acid, creatinine, aspartate transaminase (AST), lactate dehydrogenase, bilirubin, albumin, fraction of inspired oxygen:oxygen saturation (FIO2:SaO2) ratio, platelet count, MPV, MPV:platelet ratio, fibrinogen, and seizures. The combined adverse maternal outcomes included maternal death; 1 or more of hepatic failure, hematoma, or rupture; Glasgow coma scale <13; stroke; 2 or more seizures; cortical blindness; positive inotrope support; myocardial infarction; infusion of any third antihypertensive; dialysis; renal transplantation; > or =50% FIO2 for >1 hour; intubation; or transfusion of > or =10 units of blood products. Descriptive, univariable, and multivariable analyses were performed, with significance set at P < .05. RESULTS: Of a total of 594 women with preeclampsia, 60 (10.1%) developed at least 1 element of the combined adverse outcome; 1 of these 60 women died. The most common outcomes were increased oxygen requirements, the use of a third infused antihypertensive, and transfusion >10 units. In women who developed an adverse outcome, GA and fibrinogen were lower, and total leukocyte count, creatinine, and AST were greater. Multivariable logistic regression revealed that admission GA (odds ratio [OR], 0.91), dipstick protein (OR, 1.31), and MPV:platelet ratio (OR, 391.0) independently predicted the outcome. CONCLUSIONS: Several promising markers were identified: admission GA, dipstick proteinuria, and the MPV:platelet ratio. MPV:platelet ratio also showed promise as a marker of platelet consumption. A prospective study is required to develop a clinical prediction model for preeclampsia.

An admixture of 3 mg x kg(-1) of propofol and 3 mg x kg(-1) of thiopentone reduces pain on injection in pediatric anesthesia.

PURPOSE: To evaluate the incidence of pain on injection in children during anesthetic induction with a 3:1.2 volume admixture of 1% propofol and 2.5% thiopentone (P/T) compared to a 10:1 volume admixture of 1% propofol and 2% lidocaine (P/L). METHODS: After Ethics Committee approval and informed written parental consent, 127 children, aged one to ten years were studied and randomized into two groups; Group P/L received an induction with 5 mg x kg(-1) of 1% propofol and 1 mg x kg(-1) of lidocaine, Group P/T with 3 mg x kg(-1) of 1% propofol and 3 mg x kg(-1) of 2.5% thiopentone in a standardized fashion. A single, blinded observer scored pain behaviour defined as a motor response of the arm, a verbal complaint of pain, cry and/or one of three standardized facial expressions of pain. RESULTS: The incidence of pain was 14% in the P/T group, compared to 35% in the P/L group (chi(2)(1) = 7.5, P = 0.006). Motor response was the most frequent pain response in the P/L group (68%). CONCLUSION: The P/T admixture is a practical and efficacious alternative to P/L for reducing pain on induction in children. Further work to evaluate the optimum proportions and possible adverse effects of this admixture should be done.

The association between early membrane rupture, latency, clinical chorioamnionitis, neonatal infection, and adverse perinatal outcomes in twin pregnancies complicated by preterm prelabour rupture of membranes.

The objective of this study was to evaluate associations between adverse outcomes in twin pregnancies and preterm prelabour rupture of membranes (PPROM). A chart review of 246 consecutive twin pregnancies with confirmed PPROM was conducted. Regression analysis (beta [natural log of the odds ratio] and odds ratio [OR]) was performed to identify independent predictors. Two hundred and forty-six twin pregnancies, 492 liveborns, and 20 neonatal deaths. Mean (SD) PPROM gestational age (GA): 31.3 (3.8) wk; delivery GA: 32.0 (3.3) wk. PPROM < 30 wk was associated with increased parity (OR: 2.66), and log (admission leukocyte count) (OR: 9.99). Shortened latency was associated with PPROM GA (beta = -0.17) and chorioamnionitis (beta = 0.95). Neonatal sepsis was predicted by lower delivery GA (OR: 2.04). Adverse perinatal outcomes were protected against by older GA at PPROM (OR 0.53) and shortened latency (OR 0.73). It was concluded that increased leukocytosis and parity implies an infectious aetiology in earlier PPROM. Increased risk for neonatal sepsis at earlier delivery GA is consistent with gestation-dependent fetal immunocompetence. Early PPROM and long latencies were associated with increased adverse perinatal outcomes.