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The purpose of this study is to develop and compare model choice strategies in context of logistic regression. Model choice means the choice of the covariates to be included in the model.

A single dose of 2 g of tinidazole was preoperatively given to 51 patients who underwent vaginal surgery; 60 patients served as controls. The overall infection rate of the operation site was 5.9% (3/51) in the tinidazole group and 25.0% (15/60) in the control group. The difference was significant. [ABSTRACT FROM PUBLISHER]

Concentrations of metronidazole and tinidazole were analysed in mother's serum, placental tissue and foetal tissue after a single intravenous infusion of 500 mg of either drug in 21 patients who underwent a first trimester legal abortion. At the time of the evacuation (60 min from the start of the infusion) the concentrations of metronidazole and tinidazole in serum were 13.6 +/- 0.6 micrograms/ml and 13.2 +/- 0.4 micrograms/ml, respectively. In foetal tissue the concentrations of metronidazole and tinidazole reached 66% and 58%, and in placental tissue 26% and 37%, of the respective serum values. [ABSTRACT FROM AUTHOR]

Wind is a significant cause of power outages in overhead line networks. Present electricity distribution network management systems provide an extensive amount of data on network faults. These data combined with the openly available weather and soil information allow to analyze the impact of wind and soil frost on electricity system reliability more accurately than in the past. The objective is to determine the effect of soil frost on wind-induced faults in the electricity distribution system and identify variables that provide the best correlation between wind speed and the number of power supply interruptions. Five geographical areas in Finland are analyzed based on extensive electricity distribution interruption statistics collected in the country between 2008 and 2018. We introduce a methodology to analyze the effect of wind speed and soil frost and present numerical data analyzed for the areas under consideration. The methodology employs a multivariate linear regression model to show the dependence between wind, soil frost, and power supply interruptions. The results indicate that there is a strong positive correlation between the number of power supply interruptions and wind speed, and furthermore, in the multivariate model, adding the variable of soil frost improves correlation in all the areas under consideration. On average, the correlation with wind gusts and the number of power supply interruptions is approximately 0.67. However, with the soil frost variable, the correlation increases to 0.72. The results show that soil frost should be considered in studies on interruption modeling in Nordic conditions., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

Background: Information about social mixing patterns under heavy social distancing is needed to model the impact of nonpharmaceutical interventions on SARS-CoV-2 transmission., Methods: We conducted a survey on daily person-to-person contacts during the early phase of the SARS-CoV-2 epidemic in Finland, one month after strong social distancing measures had been introduced nationwide. We defined a contact as exchange of at least a few words in proximity of another person. We also considered physical ("skin-to-skin") contacts separately. Based on 3,171 reported contacts by 1,320 participants of 1-79 years of age, we estimated age-stratified contact matrices essential in modeling virus transmission., Results: Compared with contacts during prepandemic conditions, as learned from the Finnish part of the Polymod study, there was a 72% (95% credible interval, CI = 71, 74) reduction in the daily number of all contacts and a 69% (95% CI = 66, 73) reduction in the daily number of physical contacts in April 2020. The largest reduction, of almost 90%, occurred in physical contacts by individuals more than 70 years of age. The estimated reduction in the transmission potential of the virus attributable solely to reduced contact frequencies varied between 59% (whole population; physical contacts; 95% CI = 52, 68) and 77% (over 20-year olds; physical contacts; 95% CI = 70, 89)., Conclusions: We surmise that the large reduction in the daily numbers of social contacts in the early part of the SARS-CoV-2 epidemic in Finland was likely a major contributor to the steady decline of the epidemic in the country since early April., Competing Interests: The authors report no funding and conflicts of interest., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Machine learning methods have gained increased popularity in biomedical research during the recent years. However, very few of them support the analysis of longitudinal data, where several samples are collected from an individual over time. Additionally, most of the available longitudinal machine learning methods assume that the measurements are aligned in time, which is often not the case in real data. Here, we introduce a robust longitudinal machine learning method, named likelihood contrasts (LC), which supports study designs with unaligned time points. Our LC method is a binary classifier, which uses linear mixed models for modelling and log-likelihood for decision making. To demonstrate the benefits of our approach, we compared it with existing methods in four simulated and three real data sets. In each simulated data set, LC was the most accurate method, while the real data sets further supported the robust performance of the method. LC is also computationally efficient and easy to use.

Genetic predisposition could be assumed to be causing clustering of autoimmunity in individuals and families. We tested whether HLA and non-HLA loci associate with such clustering of autoimmunity. We included 1,745 children with type 1 diabetes from the Finnish Pediatric Diabetes Register. Data on personal or family history of autoimmune diseases were collected with a structured questionnaire and, for a subset, with a detailed search for celiac disease and autoimmune thyroid disease. Children with multiple autoimmune diseases or with multiple affected first- or second-degree relatives were identified. We analysed type 1 diabetes related HLA class II haplotypes and genotyped 41 single nucleotide polymorphisms (SNPs) outside the HLA region. The HLA-DR4-DQ8 haplotype was associated with having type 1 diabetes only whereas the HLA-DR3-DQ2 haplotype was more common in children with multiple autoimmune diseases. Children with multiple autoimmune diseases showed nominal association with RGS1 (rs2816316), and children coming from an autoimmune family with rs11711054 (CCR3-CCR5). In multivariate analyses, the overall effect of non-HLA SNPs on both phenotypes was evident, associations with RGS1 and CCR3-CCR5 region were confirmed and additional associations were implicated: NRP1, FUT2, and CD69 for children with multiple autoimmune diseases. In conclusion, HLA-DR3-DQ2 haplotype and some non-HLA SNPs contribute to the clustering of autoimmune diseases in children with type 1 diabetes and in their families.

Recently, tumour budding (TB) has been suggested as a strong prognostic marker in oesophageal cancer. The aim of this systematic review is to test the prognostic value of TB in oesophageal cancer by a meta-analysis of previously published studies. We systematically reviewed the literature related to TB by using the bibliographic databases of Scopus, PubMed, and Web of Science. The search was limited to publications in the English language up to and including December 2014. There are 11 retrospective studies in which TB has been evaluated in oesophageal cancer. Two authors independently extracted the results from eligible studies. The meta-analysis of eligible studies revealed that TB is a significant prognosticator for overall survival in oesophageal cancer, with a risk ratio (RR) of 2.97 [95% confidence interval (CI) 1.81-4.85; P = 0.0023] in univariate analysis, and with an RR of 2.07 (95% CI 1.22-3.52; P = 0.017) in multivariate analysis. We conclude that a high TB score is a promising prognostic marker of poor survival in oesophageal cancer. Because of its simplicity, reproducibility and high predictive power, TB is strongly recommended to be included in the routine pathology report of oesophageal cancer., (© 2015 John Wiley & Sons Ltd.)

Conflict arises among social organisms when individuals differ in their inclusive-fitness interests. Ant societies are excellent models for understanding how genetic relatedness mediates conflict intensity. However, although conflicts within colonies typically arise over offspring production, the role of larvae as actors in social conflict has received little attention. We develop and empirically test kin-selection theory of larval egg cannibalism in ant societies. Specifically, we investigate how selection for cannibalism is mediated by nestmate relatedness and larval sex in a mathematical model and then test the model's predictions by measuring cannibalism levels in eight ant species with varying nestmate relatedness. In line with our theoretical predictions, cannibalism levels in larvae were significantly influenced by relatedness and sex. Increased relatedness was associated with reduced levels of cannibalism, indicating that larval behavior is mediated by inclusive-fitness considerations. Levels of cannibalism were significantly higher in male larvae, and our model suggests that this is due to sex differences in the benefits of cannibalism. By examining the selfish interests of larvae and the constraints they face in a social environment, our study presents a novel perspective on conflict in ants and on the evolution of selfish elements in social systems in general.

Understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. Postglacial fishes are excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete environments with variation in available niches. Here, we combine data of niche utilization, trophic morphology, and 17 microsatellite loci to investigate the diversification process of three sympatric European whitefish morphs from three northern Fennoscandian lakes. The morphological divergence in the gill raker number among the whitefish morphs was related to the utilization of different trophic niches and was associated with reproductive isolation within and across lakes. The intralacustrine comparison of whitefish morphs showed that these systems represent two levels of adaptive divergence: (1) a consistent littoral-pelagic resource axis; and (2) a more variable littoral-profundal resource axis. The results also indicate that the profundal whitefish morph has diverged repeatedly from the ancestral littoral whitefish morph in sympatry in two different watercourses. In contrast, all the analyses performed revealed clustering of the pelagic whitefish morphs across lakes suggesting parallel postglacial immigration with the littoral whitefish morph into each lake. Finally, the analyses strongly suggested that the trophic adaptive trait, number of gill rakers, was under diversifying selection in the different whitefish morphs. Together, the results support a complex evolutionary scenario where ecological speciation acts, but where both allopatric (colonization history) and sympatric (within watercourse divergence) processes are involved.

In this article, we develop an admixture F model (AFM) for the estimation of population-level coancestry coefficients from neutral molecular markers. In contrast to the previously published F model, the AFM enables disentangling small population size and lack of migration as causes of genetic differentiation behind a given level of F(ST). We develop a Bayesian estimation scheme for fitting the AFM to multiallelic data acquired from a number of local populations. We demonstrate the performance of the AFM, using simulated data sets and real data on ninespine sticklebacks (Pungitius pungitius) and common shrews (Sorex araneus). The results show that the parameterization of the AFM conveys more information about the evolutionary history than a simple summary parameter such as F(ST). The methods are implemented in the R package RAFM.

While it is well understood that the pace of evolution depends on the interplay between natural selection, random genetic drift, mutation, and gene flow, it is not always easy to disentangle the relative roles of these factors with data from natural populations. One popular approach to infer whether the observed degree of population differentiation has been influenced by local adaptation is the comparison of neutral marker gene differentiation (as reflected in FST) and quantitative trait divergence (as reflected in QST). However, this method may lead to compromised statistical power, because FST and QST are summary statistics which neglect information on specific pairs of populations, and because current multivariate tests of neutrality involve an averaging procedure over the traits. Further, most FST-QST comparisons actually replace QST by its expectation over the evolutionary process and are thus theoretically flawed. To overcome these caveats, we derived the statistical distribution of population means generated by random genetic drift and used the probability density of this distribution to test whether the observed pattern could be generated by drift alone. We show that our method can differentiate between genetic drift and selection as a cause of population differentiation even in cases with FST=QST and demonstrate with simulated data that it disentangles drift from selection more accurately than conventional FST-QST tests especially when data sets are small.

The heterogametic sex chromosomes (i.e. mammalian Y and avian W) do not usually recombine with the homogametic sex chromosomes which is known to lead into rapid degeneration of Y and W due to accumulation of deleterious mutations. On the other hand, some 96% of amphibian species have homomorphic, i.e. non-degenerate Y chromosomes. Nicolas Perrin's fountain-of-youth hypothesis states that this is a result of recombination between X and Y chromosomes in sex-reversed individuals. In this study, I model the consequences of such recombination for the dynamics of a deleterious mutation occurring in Y chromosomes. As expected, even relatively low levels of sex reversal help to purge deleterious mutations. However, the population-dynamic consequences of this depend on the type of selection that operates on the population undergoing sex reversal. Under fecundity selection, sex reversal can be beneficial for some parameter values, whereas under survival selection, it seems to be always harmful.

The concentrations of erythromycin (E) and 2'-acetyl erythromycin (2'-AE) in female pelvic organs, i.e. endometrium, myometrium, ovary and Fallopian tube, as well as in plasma, were determined after oral dosing of erythromycin acistrate (EA, CAS 96128-89-1), a erythromycin prodrug. Ten patients undergoing selective gynecological operation were given three doses of EA (400 mg) at 8-h intervals immediately before the operation. Tissue samples were taken 75-205 min after the intake of the last dose. Blood samples were collected immediately prior to and up to 8 h after the intake of the last dose. High total antibiotic (erythromycin + 2'-acetyl erythromycin) concentration in plasma were measured throughout the dose interval after the last dose. The concentrations of E in plasma were over the MICs for most of the erythromycin-sensitive bacteria (0.5 micrograms/ml) in 7 out of 10 patients (mean 0.66 micrograms/ml) at the end of the third dose interval. The drug concentrations in tissues were lower than in plasma (due to short treatment time of totally 24 h). The mean percentage of penetration (tissue/plasma ratios) for erythromycin ranged from 63 to 95% in various pelvic tissues. However, rather extensive interindividual variation was observed. The degree of hydrolysis of 2'-acetyl erythromycin to erythromycin was 29-39% in plasma and 42-73% in tissue samples. There were negligible amounts of inactive anhydro forms in plasma after EA and their concentrations in tissue samples were low, as well.

The haemodynamic effects in the early phase of canine acute experimental pancreatitis (AP) were studied using a cardiac catheterization technique. AP was induced in anaesthetized dogs with an infusion of trypsin-sodium-taurocholate into the pancreatic duct. The initial haemodynamic measurements were performed after the preparation of the animal and 5 min after the induction of AP. Thereafter, pressure and volume parameters were measured at 10 min intervals. AP induced significant increases in heart rate, dP/dtmax and mean arterial pressure, but a decrease in Vmax 5 min after the induction of AP. After the initial phase, the heart rate remained significantly increased, while constant and significant decreases of stroke volume, cardiac output, end-diastolic volume and end-diastolic pressure developed. The parameters of the contractility of the left ventricle were not affected to the same extent. It is suggested that the circulatory failure observed in AP, characterised by a prompt reduction of cardiac output, was primarily due to a heavy reduction in preload. This supports the theory that cardiac output is primarily affected by impaired venous return with consequently decreased preload rather than by a loss of ventricular contractility. Hence, the existence of a myocardial depressant factor in the early phase of experimental AP does not gain support from the present results.

A single dose of 2 g tinidazole was given preoperatively to 70 patients undergoing elective hysterectomy; 76 patients served as controls. One patient in the drug therapy group and 10 in the control group had a temperature of 38 degrees C at some time after the first postoperative day. One patient in the tinidazole group and seven among the controls had abscess formation. The differences between the tinidazole and the control groups were highly significant. This simple prophylactic procedure reduced treatment costs and minimised infection following hysterectomy.

The effect of experimental acute hemorrhagic pancreatitis on hemodynamics and systolic time intervals were studied simultaneously by catheterization in dogs. Following the initial hemodynamic measurements pancreatitis was induced by a mixture of trypsin and sodium taurocholate infused into the pancreatic duct (PG, n = 7). After 60 min of surveillance the hemodynamic measurements were repeated and the results were compared to those obtained from the sham-operated group (CG, n = 7) paced at a similar contraction frequency to the PG after the follow-up time. Left ventricular ejection time (LVET) and the ratio of PEP/LVET (PEP, preejection period) increased more in the PG than in the CG (P less than 0.05 and P less than 0.001, respectively). This was related to a lower left ventricular end-diastolic volume and pressure in the PG in comparison to the CG (P less than 0.05). PEP remained unaltered in both groups during the interventions. No significant differences between the groups were observed in the responses of the maximum value of the left ventricular systolic pressure rise (dP/dtmax). The ejection fraction decreased more in the PG than in the CG (P less than 0.05), which was related to the decreased end-diastolic volume in the PG (P less than 0.001). Mean aortic pressure decreased significantly in the PG (P less than 0.01). The results indicate that experimental acute hemorrhagic pancreatitis leads to altered loading conditions of the heart and causes marked alterations in the systolic phases of the contraction cycle. This model of experimental pancreatitis does not depress the myocardial contractility on the basis of these results.