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Cover crops increase carbon (C) inputs to agricultural soils, and thus have the potential to mitigate climate change through enhanced soil organic carbon (SOC) storage. However, few studies have explored the fate of belowground C inputs associated with varying root traits into the distinct SOC pools of mineral‐associated organic carbon (MAOC) particulate organic carbon (POC). Therefore, a packed 0.5 m column trial was established with 0.25 m topsoil and 0.25 m subsoil with four cover crops species (winter rye, oilseed radish, chicory, and hairy vetch) known to differ in C:N ratio and root morphology. Cover crops were 14CO2‐labeled for 3 months, and then, half of the columns were sampled to quantify root and rhizodeposition C. In the remaining columns, plant shoots were harvested and the undisturbed soil and roots were left for incubation. Bulk soil from both sampling times was subjected to a simple fractionation scheme, where 14C in the <50 and >50 μm fraction was assumed to represent MAOC and POC, respectively. The fast‐growing rye and radish produced the highest root C. The percentage loss of C via rhizodeposition (%ClvR) showed a distinct pattern, with 22% for the more branched roots (rye and vetch) and 6%–8% for the less branched roots (radish and chicory). This suggests that root morphology plays a key role in determining rhizodeposition C. After 1 year of incubation at room temperature, the remaining MAOC and POC were positively correlated with belowground inputs in absolute terms. However, topsoil MAOC formation efficiencies (cover crop‐derived MAOC remaining as a share of belowground inputs) were higher for vetch and rye (21% and 15%, respectively) than for chicory and radish (9% and 10%, respectively), suggesting a greater importance of rhizodeposition (or indirectly, root morphology) than solely substrate C:N ratio for longer term C stabilization. [ABSTRACT FROM AUTHOR]

We investigated whether immature reticulocyte fraction (IRF) and immature reticulocytes to red blood cells ratio (IR/RBC) are sensitive biomarkers for low‐dose recombinant human erythropoietin (rhEpo) treatment at sea level (SL) and moderate altitude (AL) and whether multi (FACS) or single (Sysmex‐XN) fluorescence flow cytometry is superior for IRF and IR/RBC determination. Thirty‐nine participants completed two interventions, each containing a 4‐week baseline, a 4‐week SL or AL (2,230 m) exposure, and a 4‐week follow‐up. During exposure, rhEpo (20 IU kg−1) or placebo (PLA) was injected at SL (SLrhEpo, n = 25, SLPLAn = 9) and AL (ALrhEpo, n = 12, ALPLA n = 27) every second day for 3 weeks. Venous blood was collected weekly. Sysmex measurements revealed that IRF and IR/RBC were up to ~70% (P < 0.01) and ~190% (P < 0.001) higher in SLrhEpo than SLPLA during treatment and up to ~45% (P < 0.001) and ~55% (P < 0.01) lower post‐treatment, respectively. Compared with ALPLA, IRF and IR/RBC were up to ~20% (P < 0.05) and ~45% (P < 0.001) lower post‐treatment in SLrhEpo, respectively. In ALrhEpo, IRF and IR/RBC were up to ~40% (P < 0.05) and ~110% (P < 0.001) higher during treatment and up to ~25% (P < 0.05) and ~40% (P < 0.05) lower post‐treatment, respectively, compared with ALPLA. Calculated thresholds provided ~90% sensitivity for both biomarkers at SL and 33% (IRF) and 66% (IR/RBC) at AL. Specificity was >99%. Single‐fluorescence flow cytometry coefficient of variation was >twofold higher at baseline (P < 0.001) and provided larger or similar changes compared to multi‐fluorescence, albeit with smaller precision. In conclusion, IRF and IR/RBC were sensitive and specific biomarkers for low‐dose rhEpo misuse at SL and AL. [ABSTRACT FROM AUTHOR]

The liquid fraction after liquid/solid separation of biogas digestate has a high potential as a fertilizer due to its high nutrient concentration. However, the direct application of digestate in agricultural fields results in practical problems due to its voluminous nature. One solution to this could be to concentrate nutrients onto sorbents such as biochar or zeolites, which can subsequently be used as a fertilizer. This study investigated the ability of biochar and zeolite 'clinoptilolite' enriched with digestate nutrients to supply nitrogen (N) when used as a fertilizer. A pot experiment with ryegrass was conducted to test the effect of a nutrient‐enriched biochar and clinoptilolite by determining plant biomass growth and N uptake. This included untreated biochar and clinoptilolite as controls and two levels of N application (15 and 45 mg N per pot) each at two initial loading ratios (low and high). Nutrient‐enriched biochar and clinoptilolite increased plant biomass yield (up to 1.02 and 2.39 g per pot) and N uptake (up to 11.23 and 39.94 mg N per pot) compared to the untreated sorbents treatments. Initial loading ratio had a significant effect on plant biomass response and apparent N recovery (ANR) for enriched clinoptilolite, and lower initial loading ratio improved plant growth. In contrast to clinoptilolite, higher initial loading ratio resulted in higher ANR. In conclusion, our results reveal that N released from enriched clinoptilolite and biochar could be taken up by the plants, clinoptilolite performed more effectively than biochar, and initial loading ratio affected the performance of the sorbents when used as a fertilizer. [ABSTRACT FROM AUTHOR]

Social interactions in which bacteria respond to one another by modifying their phenotype are central determinants of microbial communities. It is known that interspecific interactions influence the biofilm phenotype of bacteria; a phenotype that is central to the fitness of bacteria. However, the underlying role of fundamental ecological factors, specifically coexistence and phylogenetic history, in biofilm formation remains unclear. This study examines how social interactions affect biofilm formation in multi-species co-cultures from five diverse environments. We found prevalence of increased biofilm formation among co-cultured bacteria that have coexisted in their original environment. Conversely, when randomly co-culturing bacteria across these five consortia, we found less biofilm induction and a prevalence of biofilm reduction. Reduction in biofilm formation was even more predominant when co-culturing bacteria from environments where long-term coexistence was unlikely to have occurred. Phylogenetic diversity was not found to be a strong underlying factor but a relation between biofilm induction and phylogenetic history was found. The data indicates that biofilm reduction is typically correlated with an increase in planktonic cell numbers, thus implying a behavioral response rather than mere growth competition. Our findings suggest that an increase in biofilm formation is a common adaptive response to long-term coexistence. [ABSTRACT FROM AUTHOR]

Functional data are data that can be represented by suitable functions, such as curves (potentially multi-dimensional) or surfaces. This paper gives an introduction to some basic but important techniques for the analysis of such data, and we apply the techniques to two datasets from biomedicine. One dataset is about white matter structures in the brain in multiple sclerosis patients; the other dataset is about three-dimensional vascular geometries collected for the study of cerebral aneurysms. The techniques described are smoothing, alignment, principal component analysis, and regression. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A goodness-of-fit test for continuous-time models is developed that examines if the parameter estimates are consistent with another for different sampling frequencies. The test compares parameter estimates obtained from estimating functions for downsamples of the data. We prove asymptotic results for stationary and ergodic processes, and apply the downsampling test to linear drift diffusions. Simulations indicate that the test is quite powerful in detecting non-Markovian deviations from the linear drift diffusions. [ABSTRACT FROM AUTHOR]

Problem  Human Leukocyte Antigen (HLA)-G is a class Ib gene located in the human major histocompatibility complex (MHC). Several lines of investigation indicate that the HLA-G molecule is involved in the maternal acceptance of the semi-allogenic fetus during pregnancy and in the development of tolerance. Expression of soluble HLA-G (sHLA-G) is positively correlated with successful in vitro fertilization (IVF) treatments, and aberrant expression of HLA-G in certain complications of pregnancy, such as pre-eclampsia and spontaneous abortion, has been reported. The main purpose of this study was to investigate the levels of different soluble HLA-G isoforms in maternal plasma in early and late pregnancy. Method of study  Soluble HLA-G (sHLA-G) can be detected in maternal blood, and in this study, two different isoforms of sHLA-G, namely sHLA-G1 generated by shedding of membrane-bound HLA-G1 and HLA-G generated by specific HLA-G transcripts, have been investigated early [median of 16.4 weeks of gestation (GW)] and late (median: 38.9 GW) in pregnancy in an original cohort of 580 pregnant Caucasian women. Results  Lower concentrations of sHLA-G1 were found late in pregnancy (>32 GW) in a group of women with severe pre-eclampsia compared with controls with uncomplicated pregnancies ( P = 0.029, P C = 0.09; Mann–Whitney; Logistic regression analysis: P = 0.024, OR = 0.920, 95% CI: 0.855–0.989). However, this was not the case with HLA-G5, and significantly more of the cases with severe pre-eclampsia had detectable plasma HLA-G5 compared with that of the control group ( P = 0.013, P C = 0.04; Mann–Whitney). Similar findings were not observed in women with gestational hypertension or existing hypertension continuing into pregnancy. Furthermore, there was a trend toward lower maternal plasma sHLA-G1 in a group of women with premature birth (<37 GW) compared with that of the control group ( P = 0.028, P C = 0.17; Mann–Whitney). On the contrary, HLA-G5 was lower in the control group compared with that in the premature group ( P = 0.004, P C = 0.02; Mann–Whitney). Conclusion  This study shows in line with other published studies that a high, detectable soluble HLA-G concentration in maternal plasma or serum is not mandatory for a successful pregnancy. However, complications during pregnancy, such as (severe) pre-eclampsia, spontaneous abortion, IUGR, and premature birth, are associated with a low or undetectable level of soluble HLA-G in the maternal blood circulation. Also, this study indicates that sHLA-G1 is the interesting soluble HLA-G isoform in pre-eclampsia, and that low or undetectable levels of HLA-G5 at the end of pregnancy seem to be associated with an uncomplicated normal pregnancy, whereas in severe pre-eclampsia and possibly other pregnancy complications, such as preterm birth and IUGR, the level of HLA-G5 is higher. [ABSTRACT FROM AUTHOR]

Background. The aetiology of palatally and labially located ectopic maxillary canines is multifactorial. Accordingly, early prediction of this eruptional disturbance is in most cases not possible. Aim. The purpose of this study was to analyse dental deviations in cases with either palatal or labial ectopic canines. Design. Panoramic and intra-oral radiographs from 50 patients with palatally located (38 females and 12 males) and 19 patients with labially located ectopic canines (11 females and 8 males), aged 10 years, 2 months–18 years, 1 month, were analysed. Dental deviations registered were crown and root malformations, agenesis, and eruption deviations. Registrations were performed in the maxillary incisor field and in the dentition in general. Results. The study documented that palatally as well as labially located ectopic canines can occur in dentitions without other dental deviations. Dental deviations occurred in approximately two-thirds of all cases, more often in females and in cases with palatally located canines. More than half of the females with palatally located canines had deviations in the maxillary incisors and in the dentition in general. Conclusion. Dental deviations may be considered a risk factor for maxillary canine ectopia. Early identification of patients at risk and appropriate interceptive treatment may reduce ectopic eruption of maxillary canines. [ABSTRACT FROM AUTHOR]

From a theoretical point of view, it has often been argued that the model of independent action (IA) is the most correct reference model to use for predicting the joint effect of mixtures of chemicals with different molecular target sites. The theory of IA, however, relies on a number of assumptions that are rarely fulfilled in practice. It has even been argued that, theoretically, the concentration addition (CA) model could be just as correct. In the present study, we tested the accuracy of both IA and CA in describing binary dose-response surfaces of chemicals with different molecular targets using statistical software. We compared the two models to determine which best describes data for 158 data sets. The data sets represented 98 different mixtures of, primarily, pesticides and pharmaceuticals tested on one or several of seven test systems containing one of the following: Vibrio fischeri, activated sludge microorganisms, Daphnia magna, Pseudokirchneriella subcapitata, Lemna minor, Tripleurospermum inodorum, or Stellaria media. The analyses showed that approximately 20% of the mixtures were adequately predicted only by IA, 10% were adequately predicted only by CA, and both models could predict the outcome of another 20% of the experiment. Half of the experiments could not be correctly described with either of the two models. When quantifying the maximal difference between modeled synergy or antagonism and the reference model predictions at a 50% effect concentration, neither of the models proved significantly better than the other. Thus, neither model can be selected over the other on the basis of accuracy alone. [ABSTRACT FROM AUTHOR]

Binary-mixture studies often are conducted with the aim of elucidating the effect of one specific chemical on the biological action of another. The results can be interpreted in relation to reference models by the use of response-surface analyses and isobolograms. The amount of data needed for these analyses is, however, extensive, and the experiments therefore rarely are repeated. In the present study, we investigate the reproducibility of isobole shapes of binary-mixture toxicity experiments in terms of deviation from the reference model of concentration addition (CA), dose-level dependence, and isobole asymmetry. We use data from four herbicide mixtures tested in three to five independent experiments on the aquatic test plant Lemna minor and the terrestrial plant Tripleurospermum inodorum. The results showed that the variation both within and among experiments was approximately half the size for the aquatic test system compared to the terrestrial system. As a consequence, a consistent deviation from CA could be obtained in three of four herbicide mixtures for L. minor, whereas this was only the case for one or two of the herbicide mixtures tested on T. inodorum. For one mixture on T. inodorum, both CA synergism and antagonism were detected. Dose-dependent effects could not be repeated consistently, just as the asymmetry found in some isoboles could not. The study emphasizes the importance of repeating mixture toxicity experiments, especially for test systems with large variability, and using caution when drawing biological conclusions from the test results. [ABSTRACT FROM AUTHOR]

The effect of hysterectomy on sexuality is not fully elucidated and until recently total and subtotal hysterectomies have only been compared in observational studies. To compare total abdominal hysterectomy (TAH) to subtotal abdominal hysterectomy (SAH) regarding effects on sexuality. In a Danish multicenter trial 319 women were randomized to TAH ( n = 158) or SAH ( n = 161); 185 women had self-selected TAH ( n = 80) or SAH ( n = 105) in a simultaneously conducted observational study. Women were followed for 1 year by strict data collection procedures, including postal questionnaires. Results were analyzed by intention to treat (ITT) analyses. No significant differences were observed between TAH and SAH at 1-year follow-up in both the randomized trial and the observational study regarding women's desire for sex, frequency of intercourse, frequency of orgasm, quality of orgasm, localization of orgasm, satisfaction with sexual life, and dyspareunia. None of these sexual variables changed significantly from entry to the 1-year follow-up, apart from dyspareunia, which was significantly ( p = 0.009) reduced in both intervention groups. Significant ( p < 0.05) predictors for satisfaction with sexual life after hysterectomy were the preoperative satisfaction with sexual life [odds ratio (OR) 32, 95% confidence interval (CI) 10–125], good relationship with partner (OR 50, 95% CI 9–354), physical well-being (OR 0.30, 95% CI 0.09–0.88) and hormone replacement therapy (OR 0.23, 95% CI 0.06–0.78). Both TAH and SAH significantly reduce dyspareunia without having a negative effect on sexual function. The shift toward SAH seems unwarranted. [ABSTRACT FROM AUTHOR]

Background: The effect of hysterectomy on sexuality is not fully elucidated and until recently total and subtotal hysterectomies have only been compared in observational studies.Aims: To compare total abdominal hysterectomy (TAH) to subtotal abdominal hysterectomy (SAH) regarding effects on sexuality.Methods: In a Danish multicenter trial 319 women were randomized to TAH (n = 158) or SAH (n = 161); 185 women had self-selected TAH (n = 80) or SAH (n = 105) in a simultaneously conducted observational study. Women were followed for 1 year by strict data collection procedures, including postal questionnaires. Results were analyzed by intention to treat (ITT) analyses.Results: No significant differences were observed between TAH and SAH at 1-year follow-up in both the randomized trial and the observational study regarding women's desire for sex, frequency of intercourse, frequency of orgasm, quality of orgasm, localization of orgasm, satisfaction with sexual life, and dyspareunia. None of these sexual variables changed significantly from entry to the 1-year follow-up, apart from dyspareunia, which was significantly (p = 0.009) reduced in both intervention groups. Significant (p < 0.05) predictors for satisfaction with sexual life after hysterectomy were the preoperative satisfaction with sexual life [odds ratio (OR) 32, 95% confidence interval (CI) 10-125], good relationship with partner (OR 50, 95% CI 9-354), physical well-being (OR 0.30, 95% CI 0.09-0.88) and hormone replacement therapy (OR 0.23, 95% CI 0.06-0.78).Conclusions: Both TAH and SAH significantly reduce dyspareunia without having a negative effect on sexual function. The shift toward SAH seems unwarranted. [ABSTRACT FROM AUTHOR]

Abstract. This paper deals with parametric inference for continuous-time stochastic volatility models observed at discrete points in time. We consider approximate maximum likelihood estimation: for the k th-order approximation, we pretend that the observations form a k th-order Markov chain, find the corresponding approximate log-likelihood function, and maximize it with respect to θ . The approximate log-likelihood function is not known analytically, but can easily be calculated by simulation. For each k , the method yields consistent and asymptotically normal estimators. Simulations from a model based on the Cox–Ingersoll–Ross model are used for illustration. [ABSTRACT FROM AUTHOR]