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Abstract  Recently discovered historical documents indicate that large releases of noble gases (mainly 41Ar and radioactive isotopes of Kr and Xe) from the Mayak Production Association (MPA) over the period from 1948 to 1956 may have caused considerable external exposures of both, inhabitants of Ozyorsk and former inhabitants of villages at the upper Techa River. To quantify this exposure, seven brick samples from three buildings in Ozyorsk, located 8–10 km north-northwest from the radioactive gas release points, were taken. The absorbed dose in brick was measured in a depth interval of 3–13 mm below the exposed surface of the bricks by means of the thermoluminescence (TL) and the optically stimulated luminescence (OSL) method. Generally, luminescence properties using TL were more favorable for precise dose determination than using OSL, but within their uncertainties the results from both methods agree well with each other. The absorbed dose due to natural radiation was assessed and subtracted under the assumption of the bricks to be completely dry. The weighted average of the anthropogenic dose for all samples measured by TL and OSL is 10 ± 9 and 1 ± 9 mGy, respectively. An upper limit for a possible anthropogenic dose in brick that would not be detected due to the measurement uncertainties is estimated at 24 mGy. This corresponds to an effective dose of about 21 mSv. A similar range of values is obtained in recently published dispersion calculations that were based on reconstructed MPA releases. It is concluded that the release of radioactive noble gases from the radiochemical and reactor plants at Mayak PA did not lead to a significant external exposure of the population of Ozyorsk. In addition, the study demonstrates the detection limit for anthropogenic doses in ca. 60-year-old bricks to be about 24 mGy, if luminescence methods are used. [ABSTRACT FROM AUTHOR]

Objective: Evidence on the optimal "dose" of cognitive behavioral therapy (CBT) for treating major depressive disorder is sparse. This analysis aimed to evaluate the dose-response curve in CBT using a nonlinear approach, whereby "dose" was defined as number of treatment sessions. The dose-response curve of CBT was compared to other psychotherapies and pharmacological treatments for depression., Method: A systematic review and metaregression analysis of randomized controlled trials (RCTs) examining the efficacy of CBT in adults with acute depression was conducted. Treatment arms examining other psychosocial or pharmacological interventions were also analyzed. Cubic spline metaregression techniques were used to model nonlinear dose-response curves., Results: Seventy-two studies and 7,377 participants were included. Modeling the dose-response curve between change of depression symptom severity and the number of CBT sessions resulted in a nonlinear curve characterized by a strong improvement in symptom severity from baseline within the first eight sessions. Symptom reduction continues in the further course of the treatment, but at a slower pace. A similar pattern of symptom development was found for other therapies as well, although the prominence of early improvement and overall effect sizes vary across treatment arms., Conclusion: Results imply a general tendency for the strongest alleviation of depressive symptom severity in early stages of CBT treatment, thus, if aiming at symptom alleviation, speak for short CBT interventions. However, these findings have to be discussed in the light of the limited data regarding the sustainability of treatment effects in short-term therapies and effects beyond symptomatic changes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Gambling usually involves wagering real money but can also be conducted with virtual money, chips, or coins. This phenomenon is sometimes referred to as simulated gambling, social gambling, or play money gambling. This study explores correlations and transitions between simulated gambling and real money gambling with an emphasis on gambling-related harms and public health concerns. The analysis is based on a national representative survey of 46,136 German Internet users which included 5,191 real money online gamblers (RMG), 54% of whom had also participated in simulated gambling (SG). The data set is divided into subsamples based on participation in SG to carve out significant differences in these groups in regard to various socio demographics, gambling patterns, and gambling problems. Regression models are used to predict RMG frequency, participation in SG, SG participation frequency, and problem gambling. The results show a clear proximity between SG and RMG with 17% of the total sample and 54% of problem gamblers reporting being "quite sure" or "certain" that simulated gambling had led them to gambling with real money. While 7% of individuals that engaged exclusively in RMG showed gambling problems, the rate is 33% for those that engaged in both RMG and SG. Regression results provide further evidence of a relationship between SG and problem gambling, although with differing effect sizes for different game forms. We argue that SG can be both a substitute and a primer for RMG, especially for problem gamblers., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Online gambling has demonstrated a significant and growing impact on overall gambling involvement. To examine online gambling practices and associated problems, we conducted surveys with national samples of Internet users in several European countries. The objective of this paper is to provide a portrait of online gambling practices and problems in five European countries (i.e., France, Italy, Germany, Switzerland, and Poland) with different online gambling regulatory systems. This paper is the first presenting national comparisons of online gambling practices. Participants reported on their gameplay patterns, demographic characteristics, gambling-related problems, gambling frequency, average spending on different online gambling activities, and offline gambling participation over the past 12 months. The Problem Gambling Severity Index was used to assess the severity of gambling problems in relation to online gambling (Ferris & Wynne, 2001 in The Canadian Problem Gambling Index: Final report, Canadian Centre on Substance Abuse, 2001). Pairwise logistic regressions examined the association between problem gambling and sociodemographic variables as well as gambling patterns and problem gambling. In all countries except Italy, the most popular online gambling activity was lotteries with nearly three quarters of participants reporting participation. The prevalence of at-risk and problem gambling was high in all countries with Poland reporting the highest prevalence and Switzerland the lowest. Gamblers who participated in gambling activities other than lottery were more likely to experience gambling-related problems. The rates in the present study are well above the levels usually found in surveys. High online gambling frequency, high spending, and participation in multiple online gambling activities were significantly associated with experiencing gambling-related problems., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Pay-to-Win gaming describes a common type of video game design in which players can pay to advance in the game. The frequency and value of payments is unlimited, and payments are linked to players' competitiveness or progress in the game, which can potentially facilitate problematic behavioral patterns, similar to those known from gambling. Our analyses focus on assessing similarities and differences between Pay-to-Win and different forms of gambling. Based on a survey among 46,136 German adult internet users, this study presents the demographic and socio-economic profile of (1) Pay-to-Win gamers who make purchases in such games, (2) heavy users who conduct daily payments, and (3) gamers who are also gamblers. Motives for making payments were assessed and participation, frequency and spending in gambling by Pay-to-Win gamers are presented. To assess the similarity of Pay-to-Win gaming and gambling, we tested whether Pay-to-Win participation, frequency of payments and problematic gaming behavior are predictors for gambling and cross-tested the opposite effects of gambling on Pay-to-Win. We find that Pay-to-Win gamers are a distinct consumer group with considerable attraction to gambling. High engagement and problematic behavior in one game form affects (over)involvement in the other. Common ground for Pay-to-Win gaming and gambling is the facilitation of recurring payments., (© 2021. The Author(s).)

Biomaterials of natural origin have recently gained increasing attention in the field of dental implantology. The requirements for such materials, however, are very high. In addition to high clinical efficiency in tissue regeneration, wound healing should be demonstrably positively influenced. The translational division for regenerative orofacial medicine of the Clinic and Polyclinic for Oral and Maxillofacial Surgery of the University Medical Center Hamburg-Eppendorf (UKE) is examining this research topic by investigating which innovative treatment methods for the reconstruction of bone defects or for augmentative procedures can be applied in the future or are already being applied in the field of oral and maxillofacial surgery., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2022 Smeets et al.)

Oral wounds are among the most troublesome injuries which easily affect the patients' quality of life. To date, the development of functional antibacterial dressings for oral wound healing remains a challenge. In this regard, we investigated antibacterial silk protein-based membranes for the application as wound dressings in oral and maxillofacial surgery. The present study includes five variants of casted membranes, i.e., i) membranes-silver nanoparticles (CM-Ag), ii) membranes-gentamicin (CM-G), iii) membranes-control (without functionalization) (CM-C), iv) membranes-silk sericin control (CM-SSC), and v) membranes-silk fibroin/silk sericin (CM-SF/SS), and three variants of nonwovens, i.e., i) silver nanoparticles (NW-Ag), ii) gentamicin (NW-G), iii) control (without functionalization) (NW-C). The surface structure of the samples was visualized with scanning electron microscopy. In addition, antibacterial testing was accomplished using agar diffusion assay, colony forming unit (CFU) analysis, and qrt-PCR. Following antibacterial assays, biocompatibility was evaluated by cell proliferation assay (XTT), cytotoxicity assay (LDH), and live-dead assay on L929 mouse fibroblasts. Findings indicated significantly lower bacterial colony growth and DNA counts for CM-Ag with a reduction of bacterial counts by 3log levels (99.9% reduction) in CFU and qrt-PCR assay compared to untreated control membranes (CM-C and CM-SSC) and membranes functionalized with gentamicin (CM-G and NW-G) (p < 0.001). Similarly, NW-G yielded significantly lower DNA and colony growth counts compared to NW-Ag and NW-C (p < 0.001). In conclusion, CM-Ag represented 1log level better antibacterial activity compared to NW-G, whereas NW-G showed better cytocompatibility for L929 cells. As data suggest, these two membranes have the potential of application in the field of bacteria-free oral wound healing. However, provided that loading strategy and cytocompatibility are adjusted according to the antibacterial agents' characteristic and fabrication technique of the membranes., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Temporomandibular joint osteoarthritis (TMJ-OA) is a chronic degenerative disease that is often characterized by progressive impairment of the temporomandibular functional unit. The aim of this randomized controlled animal trial was a comparative analysis regarding the chondroregenerative potency of intra-articular stem/stromal cell therapy. Four weeks after combined mechanical and biochemical osteoarthritis induction in 28 rabbits, therapy was initiated by a single intra-articular injection, randomized into the following groups: Group 1: AB Serum (ABS); Group 2: Hyaluronic acid (HA); Group 3: Mesenchymal stromal cells (STx.); Group 4: Mesenchymal stromal cells in hyaluronic acid (HA + STx.). After another 4 weeks, the animals were euthanized, followed by histological examination of the removed joints. The histological analysis showed a significant increase in cartilage thickness in the stromal cell treated groups (HA + STx. vs. ABS, p = 0.028; HA + ST.x vs. HA, p = 0.042; STx. vs. ABS, p = 0.036). Scanning electron microscopy detected a similar heterogeneity of mineralization and tissue porosity in the subchondral zone in all groups. The single intra-articular injection of a stem cell containing, GMP-compliant advanced therapy medicinal product for the treatment of iatrogen induced osteoarthritis of the temporomandibular joint shows a chondroregenerative effect.

For the post-surgical treatment of oral wounds and mucosal defects beyond a certain size, the gold standard is still an autologous skin or mucosal graft in combination with complex suturing techniques. A variety of techniques and biomaterials has been developed for sutureless wound closure including different tissue glues or collagen patches. However, no wound covering that enables for sutureless fixation has yet been introduced. Thus, a new system was developed that allows for sutureless wound covering including a transparent collagen membrane, which can be attached to the mucosa using a specially modified 2λ laser beam with integrated temperature sensors and serum albumin as bio-adhesive. The sutureless wound closure system was tested for its applicability and its cytocompatibility by an established in vitro model in the present study. The feasibility of the laser system was tested ex vivo on a porcine palate. The in vitro cytocompatibility tests excluded the potential release of toxic substances from the laser-irradiated collagen membrane and the bio-adhesive. The results of the ex vivo feasibility study using a porcine palate revealed satisfactory mean tensile strength of 1.2-1.5 N for the bonding of the membrane to the tissue fixed with laser of 980 nm. The results suggest that our newly developed laser-assisted wound closure system is a feasible approach and could be a first step on the way towards a laser based sutureless clinical application in tissue repair and oral surgery.

Gain or loss-of-function mutations in fibroblast growth factor receptor 3 (FGFR3) result in cranial vault defects highlighting the protein's role in membranous ossification. Zebrafish express high levels of fgfr3 during skull development; in order to study FGFR3's role in cranial vault development, we generated the first fgfr3 loss-of-function zebrafish (fgfr3 lof/lof ). The mutant fish exhibited major changes in the craniofacial skeleton, with a lack of sutures, abnormal frontal and parietal bones, and the presence of ectopic bones. Integrated analyses (in vivo imaging and single-cell RNA sequencing of the osteoblast lineage) of zebrafish fgfr3 lof/lof revealed a delay in osteoblast expansion and differentiation, together with changes in the extracellular matrix. These findings demonstrate that fgfr3 is a positive regulator of osteogenesis. We conclude that changes in the extracellular matrix within growing bone might impair cell-cell communication, mineralization, and new osteoblast recruitment. © 2020 American Society for Bone and Mineral Research., (© 2020 American Society for Bone and Mineral Research.)

Background: Clinical practice guidelines are not easily implemented, leading to a gap between research synthesis and their use in routine care., Aims: To summarise the evidence relating to the impact of guideline implementation on provider performance and patient outcomes in mental healthcare settings, and to explore the performance of different strategies for guideline implementation., Method: A systematic review of randomised controlled trials, controlled clinical trials and before-and-after studies comparing guideline implementation strategies v. usual care, and different guideline implementation strategies, in patients with severe mental illness., Results: In total, 19 studies met our inclusion criteria. The studies did not show a consistent positive effect of guideline implementation on provider performance, but a more consistent small to modest positive effect on patient outcomes., Conclusions: Guideline implementation does not seem to have an impact on provider performance, nonetheless it may influence patient outcomes positively., (© The Royal College of Psychiatrists 2017.)

Purpose of Review: Clinical practice guidelines in mental healthcare are viewed as an essential asset if appropriately developed and implemented. The purpose of this article was to review the existing literature on how guidelines should be implemented to optimize their impact on provider performance and patient outcomes in specialist mental healthcare settings., Recent Findings: Findings from recent studies suggest a trend toward an improvement in process and patient outcomes following guideline implementation. However, studies are heterogeneous in terms of design, implementation strategies and outcome measures, making it very difficult to draw firm conclusions about which implementation strategy is effective in different healthcare contexts., Summary: Current knowledge about how guidelines should be implemented is still sparse and inconclusive in mental healthcare. Future studies should attempt to employ more rigorous designs, including random allocation of patients or clusters of patients, to shed further light on this compelling issue. Research on guideline implementation strategies should additionally take into account potential barriers to knowledge translation, which can heavily influence the implementability of treatment recommendations.

Electronic gambling offers the opportunity to analyze huge and unbiased data sets of automatically recorded actual gambling behavior. This study refers to data on 2,127,887 poker playing identities from the Online Poker Database of the University of Hamburg (OPD-UHH) to analyze three subgroups of gamblers: regulars, newcomers, and dropouts. Their gambling habits over 6 months are analyzed in total, as well as over time. Regulars show a much higher involvement than non-regulars and increase their playing volume slightly over the observation period. Newcomers have a lower involvement than non-newcomers and most of them decrease their playing volume over time. Still, there is a small group of newcomers which increases their playing volume sharply and is, hence, very interesting for the industry as well as for the early prevention of pathological gambling. Dropouts have a higher gambling involvement than newcomers but play less than players who have not stopped stop gambling. Most dropouts also show a decreasing playing volume before dropping out. An analysis of the correlations between different variables of gambling habits shows that most of them reinforce each other, for example: gamblers with a higher total playing time tend to play at more tables simultaneously. Only playing frequency is a moderating variable of gambling involvement.

Objective: To investigate in vertigo patients in routine practice to what extent a rapid and straightforward triple bedside test (spontaneous nystagmus, head-shaking nystagmus, and the head impulse test) can predict a normal result on caloric testing., Study Design: Prospective, single-blind, diagnostic study., Setting: Tertiary referral center., Patients: 151 patients (78 male and 73 female subjects; mean age, 52.5 +/- 16.4 yr) presenting with acute or recent symptoms of vertigo., Intervention: Diagnostic evaluation., Main Outcome Measure: The negative predictive value (NPV) of the triple test in relation to a normal caloric test response., Results: In unilateral weakness (UW) on caloric testing (UW, >=25%), the triple test had sensitivity of 63.6%, specificity of 85.4%, a positive predictive value (PPV) of 71.4%, and an NPV of 80.4%. In other words, 80.4% of patients with a negative triple test also had a normal response on caloric testing. In pronounced canal paresis (UW, >=50%), the triple test had sensitivity of 81.8%, specificity of 81.4%, a PPV of 55.1%, and an NPV of 94.1%. Significant differences were found between 2 subgroups assessed by examiners with differing levels of experience (p < 0.05)., Conclusion: The triple test represents a good screening tool that quickly and reliably excludes unilateral weakness and in particular pronounced canal paresis on caloric testing., ((C) 2013 Otology & Neurotology, Inc.)

The color darkening of selected brushstrokes of Georges Seurat's A Sunday on La Grande Jatte--1884 was noted as early as 1892. Artificial aging of model systems containing zinc yellow (K(2)O·4ZnCrO(4)·3H(2)O) mixed with linseed oil successfully replicated the phenomena observed on La Grande Jatte. Electron energy loss spectroscopy measurements performed on the uppermost few microns of thin sections of the paint layers (obtained with focused ion beam milling) determined that samples which turned olive green (aged at 90% RH, with SO(2) and light) contain mostly the altered species Cr(III) and that the ochre-yellow coloration of specimens aged at 50% RH with SO(2) and light is due to the presence of dichromate ions (Cr (VI)). The altered species are only present in the first few microns of paint and are likely poorly crystalline, so that they eluded other types of bulk and surface measurements, but they create a substantial color alteration at the surface of the paint films. A similar phenomenon was confirmed on a sample from La Grande Jatte, where Cr(III) and Cr(VI) dichromate ions were detected in the ochre-colored, altered brushstrokes of zinc yellow. Laboratory simulations demonstrated that the equilibrium between chromate and dichromate ions is reversible within the paint film and that the orange dichromate ions can be transformed back into bright yellow chromates by exposure to highly alkaline gases.

Recently discovered historical documents indicate that large releases of noble gases (mainly (41)Ar and radioactive isotopes of Kr and Xe) from the Mayak Production Association (MPA) over the period from 1948 to 1956 may have caused considerable external exposures of both, inhabitants of Ozyorsk and former inhabitants of villages at the upper Techa River. To quantify this exposure, seven brick samples from three buildings in Ozyorsk, located 8-10 km north-northwest from the radioactive gas release points, were taken. The absorbed dose in brick was measured in a depth interval of 3-13 mm below the exposed surface of the bricks by means of the thermoluminescence (TL) and the optically stimulated luminescence (OSL) method. Generally, luminescence properties using TL were more favorable for precise dose determination than using OSL, but within their uncertainties the results from both methods agree well with each other. The absorbed dose due to natural radiation was assessed and subtracted under the assumption of the bricks to be completely dry. The weighted average of the anthropogenic dose for all samples measured by TL and OSL is 10 +/- 9 and 1 +/- 9 mGy, respectively. An upper limit for a possible anthropogenic dose in brick that would not be detected due to the measurement uncertainties is estimated at 24 mGy. This corresponds to an effective dose of about 21 mSv. A similar range of values is obtained in recently published dispersion calculations that were based on reconstructed MPA releases. It is concluded that the release of radioactive noble gases from the radiochemical and reactor plants at Mayak PA did not lead to a significant external exposure of the population of Ozyorsk. In addition, the study demonstrates the detection limit for anthropogenic doses in ca. 60-year-old bricks to be about 24 mGy, if luminescence methods are used.

This study reports the multi-analytical investigation of ready-mixed house paints used by artists such as Pablo Picasso (1881-1973) in the first half of the twentieth century. The pigment composition of paint swatches on four historic paint sample cards from the Art Institute of Chicago reference collection was characterized by thorough screening using Fourier transform infrared (FT-IR) and X-ray fluorescence (XRF) spectroscopies, followed by Raman spectroscopy when necessary. Spectroscopic investigations highlighted the dominance of zinc-based whites, the consistent choice of particular pigments or their mixtures, as well as the avoidance of others to achieve the various hues on the sample cards. Notable findings included the documentation of strong spectroscopic signatures of metal soaps. Given the similarities in composition of early twentieth century artists' and house paints, the results indicate that the identification of house paints in works by Pablo Picasso and others must be based on a combination of parameters rather than the detection of a single chemical marker. Results have been applied to the case study of Picasso's 1935 sculpture Figure (AIC 1988.428), which incorporates direct evidence of the use of house paint by the artist.

The incidence of hyper-contracted giant fibres in pig postmortem skeletal muscle is closely related to poor meat quality in terms of pale, soft, and exudative pork. Detection of a predisposition to develop giant fibres in live pigs could help to predict pork quality and to exclude affected pigs from genetic selection. The abundance and proportion of giant fibres in longissimus muscle were highest in Piétrain followed by Landrace, Large White, and Leicoma pigs of market weight. The postmortem development of giant fibres could be successfully simulated in vitro incubating biopsy samples from longissimus muscle at 37°C for 60min. For repeated measurements on three samples the intraclass correlation coefficient for the number of giant fibres/cm(2) was ϑˆ(3)=0.69 for biopsy and ϑˆ(3)=0.87 for carcass samples. "Simulated" giant fibres exhibited ultrastructural changes in plasma membrane, myofibrils, mitochondria, and sarcoplasmatic reticulum as shown previously for giant fibres in carcass samples.

Striated muscles exhibit a wide range of metabolic activity levels. Heart and diaphragm are muscles with continuous contractile performance, which requires life-long function. In contrast, skeletal muscles like longissimus muscle can adapt metabolism from resting to different stages of exercise. The aim of this study was to compare the morphological features of these three muscles and the expression of genes that are important for energy metabolism. Therefore, histochemical studies were performed for determination of muscle fibre type composition. Oxidative and glycolytic capacity was assessed by measuring isocitrate dehydrogenase (ICDH) and lactate dehydrogenase (LDH) activities. The mRNA expression of glucose transporter 4 (GLUT 4), growth hormone receptor (GHR) and AMP-activated kinase (AMPK) alpha(1) and alpha(2) subunits was studied by semiquantitative Northern blotting. Heart, and to a slightly lesser extent diaphragm were highly oxidative muscles characterised by high expression of oxidative muscle fibres and ICDH activity. Longissimus muscle exhibited the highest percentage of glycolytic fibres and LDH activity. GLUT 4 mRNA was lowest in heart reflecting the dependency of heart muscle on fatty acids as major energy source. Higher expression of GLUT 4 in diaphragm indicated that glucose is an important energy substrate in this oxidative muscle. Highest GLUT 4 expression in longissimus should be essential for the refilling of glycogen stores after exercise. AMPK subunits, which are important stimulators of GLUT 4 protein insertion into the sarcolemma, are also highest expressed in longissimus muscle indicating the strong capacity to adapt energy metabolism to large changes in energy demand. Interestingly, AMPK alpha(1) subunit expression on protein level is strongly restricted to muscle fibres containing type I myosin in this muscle. GHR mRNA expression was also highest in longissimus muscle indicating that an enhanced effect of growth hormone, which is described to be diabetogenic, could be involved in the lower insulin sensitivity of glycolytic muscles.

Background: The proportion of muscle fibre types and their size affect muscularity as well as functional properties of the musculature and meat quality. We aimed to identify QTL for microstructural muscle properties including muscle fibre size, their numbers and fibre type proportions as well as biophysical parameters of meat quality and traits related to body composition, i.e. pH, conductivity, area of M. longissimus dorsi and lean meat content. A QTL scan was conducted in a porcine experimental population that is based on Duroc and Berlin Miniature Pig., Results: Least square regression interval mapping revealed five significant and 42 suggestive QTL for traits related to muscle fibre composition under the line-cross model as well as eight significant and 40 suggestive QTL under the half-sib model. For traits related to body composition and biophysical parameters of meat quality five and twelve significant plus nine and 22 suggestive QTL were found under the line-cross and half-sib model, respectively. Regions with either significant QTL for muscle fibre traits or significant QTL for meat quality and muscularity or both were detected on SSC1, 2, 3, 4, 5, 13, 14, 15, and 16. QTL for microstructural properties explained a larger proportion of variance than did QTL for meat quality and body composition., Conclusion: Microstructural properties of pig muscle and meat quality are governed by genetic variation at many loci distributed throughout the genome. QTL analysis under both, the line-cross and half-sib model, allows detecting QTL in case of fixation or segregation of the QTL alleles among the founder populations and thus provide comprehensive insight into the genetic variation of the traits under investigation. Genomic regions affecting complex traits of muscularity and meat quality as well as microstructural properties might point to QTL that in first instance affect muscle fibre traits and by this in second instance meat quality. Disentangling complex traits in their constituent phenotypes might facilitate the identification of QTL and the elucidation of the pleiotropic nature of QTL effects.

This paper describes the long-term behaviour of (90)Sr and (137)Cs in foods, feeds and a variety of environmental media. The long-term behaviour is quantified by means of the ecological half-life which integrates all processes that cause a decrease of activity in a given medium such as leaching, fixation and erosion. A large number of long-term time series of concentrations of radiocaesium and radiostrontium in these media have been identified and re-evaluated using a standardised statistical procedure to establish reference data sets of ecological half-lives. By example of undisturbed soils and marine water bodies it is shown that the ecological half-life concept is questionable if the distribution of the radionuclide of interest within the medium studied is non-uniform and if mixing and transport processes within this medium, therefore, are of considerable importance during the time period of observation.

The aim of this study was to alter the fatty acid composition of porcine tissue by accumulating essential fatty acids without adversely affecting carcass composition, muscle structure or meat eating quality. A total of 13 female and 12 castrated Pietrain×German Landrace pigs were fed a basal concentrate diet supplemented with 5% olive oil or 5% linseed oil during the growing-finishing period. Carcass composition and meat quality were not affected by the diet. Feeding linseed oil to pigs significantly increased the relative content of linolenic acid and long chain n-3 fatty acids in lipids of muscle, backfat and heart at the expense of arachidonic acid. Oleic acid was accumulated in muscle, backfat and heart lipids by feeding olive oil. The overall flavour of combined meat/backfat samples from castrates was negatively influenced by linseed oil supplementation compared to supplementation with olive oil. The oxidative stability of muscle lipids was lower in linseed oil-fed pigs compared to olive oil fed pigs. The greater cross section areas of the longissimus muscle of females were caused by an increased diameter of red, intermediate and white fibres.

In Longissimus muscle from a F(2) population of Duroc×Berlin Miniature Pigs, micro-structural fibre traits and fatty acid composition were investigated to calculate correlation coefficients between these traits and meat quality. The animals of the F(2) population exhibited low carcass weight (55.7±11.2 kg), low meat percentage (35.0±8.4%) but a relatively high intramuscular fat content (3.52±1.44%) compared to pure bred animals (F(0)). No unacceptable meat quality was observed. The variation coefficients of carcass composition, muscle fibre traits, and fat traits were high enough to allow the analysis of candidate genes which influence the growth of muscle fibres, fat cells, and meat quality. Phenotypic correlation coefficients between muscle fibre characteristics and meat quality traits were low whereas fatty acid composition and meat quality were more closely related. The correlation coefficients between muscle fibre traits and fatty acid composition ranged from 0.10 to 0.40. The relationship between a low quotient of n-6/n-3 fatty acids in muscle and greater fibre sizes, higher percentages of the oxidative fibre type and higher capillary density was noteworthy indicating good conditions for muscle growth and meat quality.

The objective of this study was to examine the effects of somatotropin (ST) on porcine reproductive and metabolic statuses during early pregnancy. Four pregnant crossbred gilts received 6 mg of recombinant porcine somatotropin (rpST) daily from days 10 to 27 after artificial insemination while six pregnant gilts served as controls. Blood samples were taken on days 8, 10, 12, 14, 18, 22, and 27 prior to rpST injections (8:00 h) and subsequently at 9:00, 10:00, 12:00, 14:00, 16:00, 18:00, and 20:00 h. On all remaining days of treatment, samples were taken once daily before injections (8:00 h). The samples were assayed for the metabolic hormones: ST, insulin-like growth factor I (IGF-I), insulin, thyroxine (T(4)), triiodothyronine (T(3)), and cortisol; for metabolites: free fatty acids (FFA) and glucose; and for the reproductive hormones: luteinizing hormone (LH), progesterone, estradiol-17beta, estrone sulfate, and prostaglandin F(2alpha). Delivery of rpST daily induced a 20- to 40-fold increase in plasma ST concentrations. Moreover, repeated administration of rpST resulted in a continuous increase in plasma IGF-I concentration (P < 0.001), from 191.0 +/- 22.3-340.0 +/- 15.3 ng/mL 24 h after initial injection to 591.3 +/- 46.8 ng/mL after final injections. Mean serum insulin tended to be greater in rpST-treated gilts. Blood concentrations of T(4) were reduced (P < 0.05) from day 14 of gestation in treated gilts while T(3) concentrations remained unchanged. Concentrations of both glucose and FFA were greater (P < 0.01) and cortisol concentrations were unchanged in treated gilts. Changes in reproductive steroid hormones were minimally affected. Circulating progesterone (P = 0.078), and estradiol-17beta (P = 0.087) concentrations tended to be lower in treated animals. These data show that treatment of pregnant gilts with rpST during early gestation mainly impacts metabolic rather than reproductive status., (Copyright 2002 Elsevier Science Inc.)

The purpose of this study was to evaluate the cellular compatibility of five endodontic sealers in the first 24 h after mixing. Specimens of N2, Endomethasone, Apexit, AH Plus, and Ketac Endo were extracted with cell culture medium 0, 1, 5, and 24 h after mixing. Eluates were tested for cytotoxicity with immortal 3T3 cells and primary human periodontal ligament fibroblasts using XTT-assays. Data were analyzed for statistically significant differences by means of Dunnett's t tests (p < 0.05). All extracts of N2 completely inhibited cell metabolism (p < 0.05). Similar effects were provoked by the first three eluates of Endomethasone, but the 24-h extract irritated cells significantly less (p < 0.05). Severe cytotoxicity was also observed with all Ketac Endo extracts (p < 0.05). A significant inhibition of mitochondrial activity was induced by the first (3T3) or the first and second eluate (periodontal ligament fibroblasts) of AH Plus (p < 0.05). The subsequent eluates of this sealer and all extracts of Apexit did not reveal any cytotoxic potency.

The effects of maternal treatment with somatotropin during early gestation on fetal muscle development were determined. Crossbred gilts received daily injections of either 3 ml of a placebo ( n=31) or of 6 mg porcine somatotropin ( n=31) from day (d) 10 to 27 of gestation and samples were collected from d 28 embryos, d 37 and 62 fetuses, and from neonates. Administration of somatotropin increased the total number of fibres (primary and secondary fibres) in neonatal semitendinosus muscle of middle- and low-weight littermates, whilst no increase was observed in psoas major muscle. Somatotropin induced increases in muscular protein concentration, creatine kinase activity, muscle fibre girth, as well as type II to type I fibre conversion which revealed an advanced degree of differentiation at birth. Treatment effects on prenatal development preceded these changes. Increased DNA concentrations at d 28 of gestation indicate stimulation of cellular proliferation during the embryonic stages. Thereafter, the withdrawal of somatotropin caused a transient delay of differentiation as indicated by lower protein concentrations and creatine kinase activity compared with controls at d 37 of gestation. This was compensated again at d 62, and the number of semitendinosus primary fibres was increased in middle-weight fetuses, whereas secondary or total fibre number did not yet differ. However, enhanced expression of Myf5 and MyoD indicates higher numbers of initially determined, proliferating myoblasts that may have contributed to increased formation of secondary fibres. In conclusion, maternal somatotropin is an influential factor in early pregnancy capable of affecting the basic events of myogenesis.

The objective of this study was to investigate the growth- and breed-related changes of muscle fiber characteristics in cattle and their importance to meat quality. Four cattle breeds with different growth impetus and muscularity were reared and slaughtered under experimental conditions. German Angus as a beef type, Galloway as a hardy type, Holstein Friesian as a dairy type, and double-muscled Belgian Blue as an extreme type for muscle growth were used. Between 5 and 17 bulls of each breed were slaughtered at 0, 2, 4, 6, 12, 18, and 24 mo of age. Muscle fiber traits were determined and classified by computerized image analysis, and several measures of meat quality were also determined, including shear force value, meat color, and i.m. fat content. The postnatal growth of semitendinosus muscle in cattle was characterized by a nearly 10-fold increase of muscle fiber area from birth to 24 mo of age. In the first few months after birth, a transformation of type IIA fibers into IIB fibers was found, whereas type I fibers were nearly unaffected by age. The apparent total muscle fiber number of semitendinosus muscle did not increase during postnatal life. These results confirm that the fiber number is determined in embryonic development. Throughout the study, the double-muscled Belgian Blue (BBDM) bulls had almost twice the fiber number of the other breeds, emphasizing a more extensive hyperplasia of muscle fibers during embryonic development in BBDM compared with the other three breeds. The apparent number of type I fibers was, however, not affected by breed, which suggests that the additional fibers found in BBDM postnatally were type IIB and IIA fibers. We did not find significant differences in muscle fiber total number, muscle fiber type frequencies, or meat quality characteristics among breeds, with the exception of BBDM. Having pooled the four breeds, paler meat was related to a higher frequency of type IIB fibers, a lower area of type IIA and type I fiber, and a higher total muscle fiber number. These findings based on data of double muscling give us some hints for biological causes for the variation of meat quality. Further investigation, in particular within each breed, is necessary to identify the superior fiber traits for bovine meat production.

In pigs, intensive growth of the musculature is often accompanied by malignant hyperthermia susceptibility (MHS; n gene) and poorer meat quality. Using histological and histochemical methods, different fibre characteristics in the Longissimus muscle were found in Pietrain×German Landrace pigs with this gene defect. Compared to MHS homozygous negative pigs, groups with the n gene had increased diameters of the mean fibre types and increased glycolytic metabolic potential, as shown by a higher frequency of the fast twitch glycolytic type and a lower frequency of the slow twitch oxidative fibre type. Differences between the groups were also found in the number of angular and giant fibre types. Furthermore, a positive correlation was found between the frequency of oxidative fibres and the relative enzyme activity of NADH tetrazolium reductase. The changes correlated with lower pH and higher drip loss in meat from the MHS homozygous positive group. In conclusion, the different muscle fibre characteristics can be interpreted as endogenous factors which influence the physiological condition in the muscle of the live animal and meat quality post mortem.

Different mass spectrometric approaches were used to identify an original non-terpenoid varnish. Direct temperature-resolved MS and pyrolysis-GC/MS mainly showed the phenolic components, whereas thermally assisted (trans)methylation with tetramethylammonium hydroxide (TMAH) strongly enhanced the evidence for tung oil as part of the varnish. Transethylation studies of the fatty acids confirmed the TMAH data. The degree of hydrolysis of the oil network was found to be low. No evidence was found for a direct link between the drying oil and phenolic resin. On the basis of the MS information, the aged varnish is identified as an open-structure tert-butylphenol-formaldehyde resin which entangles the tung oil polymer.

The administration of porcine somatotropin (pST) to pregnant sows during early gestation (day 10 to 24) induced the formation of significantly more muscle fibres in the semitendinosus muscle of the fetuses, representing a higher growth capacity of skeletal muscle. The pST-treatment during late pregnancy (day 80 to 94) accelerated the development of the fetus resulting in higher body weights and advanced stage of maturity at birth.