Working Hypothesis Research Articles

Simulation of Welding Residual Stresses in Large Structures – First Results of Thermal Analyses

AbstractSimulation of welding residual stresses and distortions has been applied mostly for small‐scale components, smaller than those applied in civil engineering structures, due to the high requirements in computational capacities. In the present study, work hypotheses, which can reduce the computational load of welding simulations for an accepted sacrifice in accuracy, are discussed. A series of thermal analyses is carried out, in order to check the validity of the proposed modelling approaches, which refer to the application of simple weld heat source models and hybrid shell‐solid element models. Application of local‐global models is also discussed. The present study aims to work as a first step towards the establishment of an engineering approach for the simulation of welds in civil engineering structures with sufficient accuracy and reduced requirements for computational capacity.

Words for the hearts: a corpus study of metaphors in online depression communities.

Humans understand, think, and express themselves through metaphors. The current paper emphasizes the importance of identifying the metaphorical language used in online health communities (OHC) to understand how users frame and make sense of their experiences, which can boost the effectiveness of counseling and interventions for this population. We used a web crawler to obtain a corpus of an online depression community. We introduced a three-stage procedure for metaphor identification in a Chinese Corpus: (1) combine MIPVU to identify metaphorical expressions (ME) bottom-up and formulate preliminary working hypotheses; (2) collect more ME top-down in the corpus by performing semantic domain analysis on identified ME; and (3) analyze ME and categorize conceptual metaphors using a reference list. In this way, we have gained a greater understanding of how depression sufferers conceptualize their experience metaphorically in an under-represented language in the literature (Chinese) of a new genre (online health community). Main conceptual metaphors for depression are classified into PERSONAL LIFE, INTERPERSONAL RELATIONSHIP, TIME, and CYBERCULTURE metaphors. Identifying depression metaphors in the Chinese corpus pinpoints the sociocultural environment people with depression are experiencing: lack of offline support, social stigmatization, and substitutability of offline support with online support. We confirm a number of depression metaphors found in other languages, providing a theoretical basis for researching, identifying, and treating depression in multilingual settings. Our study also identifies new metaphors with source-target connections based on embodied, sociocultural, and idiosyncratic levels. From these three levels, we analyze metaphor research's theoretical and practical implications, finding ways to emphasize its inherent cross-disciplinarity meaningfully.

Impact of PNPLA3 I148M on alpha-1 antitrypsin deficiency-dependent liver disease progression.

Genetic risk factors are major determinants of chronic liver disease (CLD) progression. Patatin-like phospholipase domain-containing protein 3 (PNPLA3) I148M polymorphism and alpha-1 antitrypsin (AAT) E342K variant, termed PiZ, are major modifiers of metabolic CLD. Both variants are known to affect metabolic CLD through increased endoplasmic reticulum stress, but their combined effect on CLD progression remains largely unknown. Here, we aimed to test our working hypothesis that their combined incidence triggers CLD disease progression. We showed that patients with PiZZ/PNPLA3 I148M from the European alpha-1-antitrypsin deficiency (AATD) liver consortium and the UK Biobank had a trend towards higher liver enzymes, but no increased liver fat accumulation was evident between subgroups. After generating transgenic mice that overexpress the PiZ variant and simultaneously harbor the PNPLA3 I148M knockin (designated as PiZ/PNPLA3 I148M ), we observed that animals with PiZ and PiZ/PNPLA3 I148M showed increased liver enzymes compared to controls during aging. However, no significant difference between PiZ and PiZ/PNPLA3 I148M groups was observed, with no increased liver fat accumulation over time. To further study the impact on CLD progression, a Western-styled diet was administered, which resulted in increased fat accumulation and fibrosis in PiZ and PiZ/PNPLA3 I148M livers compared to controls, but the additional presence of PNPLA3 I148M had no impact on liver phenotype. Notably, the PiZ variant protected PNPLA3 I148M mice from liver damage and obesity after Western-styled diet feeding. Our results demonstrate that the PNPLA3 polymorphism in the absence of additional metabolic risk factors is insufficient to drive the development of advanced liver disease in severe AATD.

Hypothesis-generating analysis of the impact of non-damaging metabolic acidosis on the transcriptome of different cell types: Integrated stress response (ISR) modulation as general transcriptomic reaction to non-respiratory acidic stress?

Extracellular pH is an important parameter influencing cell function and fate. Microenvironmental acidosis accompanies different pathological situations, including inflammation, hypoxia and ischemia. Research focussed mainly on acidification of the tumour micromilieu and the possible consequences on proliferation, migration and drug resistance. Much less is known regarding the impact of microenvironmental acidosis on the transcriptome of non-tumour cells, which are exposed to local acidosis during inflammation, hypoxia, ischemia or metabolic derailment. In the present hypothesis-generating study, we investigated the transcriptional impact of extracellular acidosis on five non-tumour cell types of human and rat origin, combining RNA-Sequencing and extensive bioinformatics analyses. For this purpose, cell type-dependent acidosis resiliences and acidosis-induced transcriptional changes within these resilience ranges were determined, using 56 biological samples. The RNA-Sequencing results were used for dual differential-expression analysis (DESeq and edgeR) and, after appropriate homology mapping, Gene Ontology enrichment analysis (g:Profiler), Ingenuity Pathway Analysis (IPA®), as well as functional enrichment analysis for predicted upstream regulators, were performed. Extracellular acidosis led to substantial, yet different, quantitative transcriptional alterations in all five cell types. Our results identify the regulator of the transcriptional activity NCOA5 as the only general acidosis-responsive gene. Although we observed a species- and cell type-dominated response regarding gene expression regulation, Gene Ontology enrichment analysis and upstream regulator analysis predicted a general acidosis response pattern. Indeed, they suggested the regulation of four general acidosis-responsive cellular networks, which comprised the integrated stress response (ISR), TGF-β signalling, NFE2L2 and TP53. Future studies will have to extend the results of our bioinformatics analyses to cell biological and cell physiological validation experiments, in order to test the refined working hypothesis here.

Conceptual engineering for analytic theology

ABSTRACT Conceptual Engineering is the method (or methods) via which we can assess and improve our concepts. Can Conceptual Engineering be usefully employed within analytic theology? Given that analytic theology and analytic philosophy effectively share the same philosophical toolkit then if Conceptual Engineering works well in philosophy then it ought to work well in analytic theology too. This will be our working hypothesis. To make good on this hypothesis, we first address two challenges. The first challenge makes conceptual engineering look to be too inclusive; the second challenge makes it look to be too revolutionary (for analytic theology). To address these challenges, we propose a refined characterisation of Conceptual Engineering. We then turn to consider a number of case studies where analytic theology and conceptual engineering may fruitfully cooperate. These are: theological disagreements, inter-faith dialogue, meaning change, celibacy, AI, the name of God and conceptual genealogy.

The Efficacy of Psychoeducational Family Intervention for Major Depression: Study Protocol of a Randomized Controlled Trial.

This study aims to assess the efficacy of a psychoeducational family intervention (PFI) to reduce the severity of depressive symptoms and to improve psychosocial functioning and to increase social contacts in a sample of patients with major depressive disorder (MDD). The degree to which PFI will reduce patients' relapses, hospitalizations, and self-stigmatization and will improve their quality of life will also be assessed. Other secondary outcomes include the improvement of relatives' coping strategies, family burden, expressed emotions and quality of life. This non-profit, unfunded, national, multicentric randomized controlled trial with blinded outcome assessments will be carried out in 24 Italian university outpatient units. Families will be assessed at baseline and at 6, 12, and 24 months post-randomization. Our working hypothesis is that the PFIs will reduce the patients' severity of depressive symptoms, their relapses, and their hospitalizations, and that they will improve their psychosocial functioning and quality of life. We expect these results to be maintained after 12 and 24 months, albeit with a reduction in magnitude. The sample will consist of 384 patients randomized at a 1:1 ratio and stratified according to center, age, gender, and educational level.

Inkjet-printed morphogenesis of tumor-stroma interface using bi-cellular bioinks of collagen-poly(N-isopropyl acrylamide-co-methyl methacrylate) mixture

Recent advances in biomaterials and 3D printing/culture methods enable various tissue-engineered tumor models. However, it is still challenging to achieve native tumor-like characteristics due to lower cell density than native tissues and prolonged culture duration for maturation. Here, we report a new method to create tumoroids with a mechanically active tumor-stroma interface at extremely high cell density. This method, named “inkjet-printed morphogenesis” (iPM) of the tumor-stroma interface, is based on a hypothesis that cellular contractile force can significantly remodel the cell-laden polymer matrix to form densely-packed tissue-like constructs. Thus, differential cell-derived compaction of tumor cells and cancer-associated fibroblasts (CAFs) can be used to build a mechanically active tumor-stroma interface. In this methods, two kinds of bioinks are prepared, in which tumor cells and CAFs are suspended respectively in the mixture of collagen and poly (N-isopropyl acrylamide-co-methyl methacrylate) solution. These two cellular inks are inkjet-printed in multi-line or multi-layer patterns. As a result of cell-derived compaction, the resulting structure forms tumoroids with mechanically active tumor-stroma interface at extremely high cell density. We further test our working hypothesis that the morphogenesis can be controlled by manipulating the force balance between cellular contractile force and matrix stiffness. Furthermore, this new concept of “morphogenetic printing” is demonstrated to create more complex structures beyond current 3D bioprinting techniques.

Targeted Glutamate Supply Boosts Insulin Concentrations, Ovarian Activity, and Ovulation Rate in Yearling Goats during the Anestrous Season.

The neuroendocrine regulation of the seasonal reproductive axis requires the integration of internal and external signals to ensure synchronized physiological and behavioral responses. Seasonal reproductive changes contribute to intermittent production, which poses challenges for optimizing goat product yields. Consequently, a significant objective in seasonal reproduction research is to attain continuous reproduction and enhance profitability in goat farming. Glutamate plays a crucial role as a modulator in several reproductive and metabolic processes. Hence, the aim of this study was to evaluate the potential impact of exogenous glutamate administration on serum insulin concentration and ovarian function during the out-of-season period in yearling goats. During the anestrous season, animals were randomly located in individual pens to form two experimental groups: (1) glutamate (n = 10, live weight (LW) = 29.1 ± 1.02 kg, body condition score (BCS) = 3.4 ± 0.2 units) and (2) control (n = 10; LW = 29.2 ± 1.07 kg, BCS = 3.5 ± 0.2), with no differences (p < 0.05) regarding LW and BCS. Then, goats were estrus-synchronized, and blood sampling was carried out for insulin quantification. Ovaries were ultrasonographically scanned to assess ovulation rate (OR), number of antral follicles (AFs), and total ovarian activity (TOA = OR + AF). The research outcomes support our working hypothesis. Certainly, our study confirms that those yearling goats treated with exogenous glutamate displayed the largest (p < 0.05) insulin concentrations across time as well as an augmented (p < 0.05) out-of-season ovarian activity.

A distinct variant of the SzM protein of Streptococcus equi subsp. zooepidemicus recruits C1q independent of IgG binding and inhibits activation of the classical complement pathway

ABSTRACT Streptococcus equi subsp. zooepidemicus (SEZ) is a major equine pathogen that causes pneumonia, abortion, and polyarthritis. It can also cause invasive infections in humans. SEZ expresses the M-like protein SzM, which recruits host proteins such as fibrinogen to the bacterial surface. Equine SEZ strain C2, which binds only comparably low amounts of human fibrinogen in comparison to human SEZ strain C33, was previously shown to proliferate in equine and human blood. As the expression of SzM_C2 was necessary for survival in blood, this study investigated the working hypothesis that SzM_C2 inhibits complement activation through a mechanism other than fibrinogen and non-immune immunoglobulin binding. Loss-of-function experiments showed that SEZ C2, but not C33, binds C1q via SzM in IgG-free human plasma. Furthermore, SzM C2 expression is necessary for recruiting purified human or equine C1q to the bacterial surface. Flow cytometry analysis demonstrated that SzM expression in SEZ C2 is crucial for the significant reduction of C3b labelling in human plasma. Addition of human plasma to immobilized rSzM_C2 and immobilized aggregated IgG led to binding of C1q, but only the latter activated the complement system, as shown by the detection of C4 deposition. Complement activation induced by aggregated IgG was significantly reduced if human plasma was pre-incubated with rSzM_C2. Furthermore, rSzM_C2, but not rSzM_C33, inhibited the activation of the classical complement pathway in human plasma, as determined in an erythrocyte lysis experiment. In conclusion, the immunoglobulin-independent binding of C1q to SzM_C2 is associated with complement inhibition.

Establishing an anthropometric database: A case for the Portuguese working population

Up-to-date anthropometric databases can help design appropriate workstations and equipment, reducing occupational accidents and disorders. The primary aim of this study was to create a company database to support the hypothesis that the latest anthropometric database for the Portuguese working population was outdated. Through the traditional manual measurement method, this work collected data on 27 dimensions from 343 workers in an industry in Northern Portugal. The interclass correlation coefficient showed high agreeability intra- and inter-evaluators with average values of 0.940 and 0.950, respectively. Socioeconomic aspects of the sample population, including gender, immigration, and age, were evaluated. Statistical analysis included correlations between the 27 anthropometric dimensions, age, and Body Mass Index (BMI). Among the main findings, men displayed larger average dimensions than women except for hip breadth, and female body measures decreased more with age than males. Men were 1.6 times more likely to be overweight than women, whereas women were twice more likely to be obese. Concerning working shifts, individuals on the night shift showed an increased tendency to be overweight or obese (BMI>25). Since the previous database employed a different method (photogrammetric), it was possible to compare only five dimensions (stature, knee height, elbow height, hip breadth, and abdominal depth) through mean absolute differences. Variations in the population stature and knee and elbow heights support this work's hypothesis and underscore the need to establish and update the Portuguese anthropometric database with a reliable and reproducible method.

Dreaming during a pandemic: Low incorporation of COVID-19-specific themes and lucidity in dreams of psychiatric patients and healthy controls.

The present study examined the impact of the COVID-19 pandemic on the emotional quality of dreams, the incorporation of pandemic-related themes, and the occurrence of lucid dreaming. Dream reports and lucidity ratings of psychiatric outpatients (n=30) and healthy controls (n=81) during two lockdowns in Germany were compared to those of healthy controls (n=33) before the pandemic. Results confirmed previous reports that pandemic-specific themes were incorporated into dreams. Overall, however, incorporation into dreams was rare. Contrary to expectations, psychiatric outpatients did not differ from controls in the frequency of dream incorporation of pandemic-related content. Moreover, incorporation was independent of psychiatric symptoms and loneliness. Loneliness was, however, associated with threat-related content, suggesting that it represents a risk for bad dreams but not for crisis-specific dream incorporation. Regarding lucid dreaming, both groups had similar scores for its underlying core dimensions, i.e., insight, control, and dissociation, during the two lockdowns. Scores for control and dissociation but not insight were lower compared to the pre-pandemic sample. Our working hypothesis is that REM sleep during lockdowns intensified as a means of increased emotional consolidation, rendering the associated mental state less hybrid and thereby less lucid.

Fungal Community Taxa Differ in Diversity and Number between Live and Dead Prunus serotina Ehrh. Wood in a Protected Forest within Its Secondary Range of Distribution

Prunus serotina is an important invasive plant species in Poland. It was introduced to European forests, even in places currently protected by law, such as national parks. One major factor contributing to the spread of this species is the lack of infecting pathogens and incomplete knowledge about the relationship between the plant and microorganisms. This study aimed to identify fungal communities collected from freshly cut stumps of live and dead black cherry tree specimens growing in a protected forest. The main working hypotheses were as follows: (i) fungal communities inhabiting the wood of dead and living trees will differ in diversity and the number of taxa; and (ii) saprotrophic fungi will dominate in the wood of dead tree stumps. This study applied Illumina sequencing based on the amplification of the fungal ribosomal ITSI region. The average number of sequences (OTU) obtained from the analysis of dead tree wood was 101,758, while that of living trees was 94,150. These sequences belonged to 312 taxa, among which 254 were isolated from the wood of dead trees and 171 from that of living trees. Among the saprotrophs on dead trees, the following species were identified: Stereum rugosum, Ganoderma adspersum, G. applanatum, Peniophora cinerea, and Ascocoryne cylichnium. On the other hand, in the wood of living trees, Cytospora leucostoma and Botrytis cinerea were the most abundant saprotrophic species. The fungal communities inhabiting the wood of dead and living trees differed in the diversity and abundance of taxa, thus confirming our hypothesis. The results of our research conducted in a protected area indicate that black cherry wood can be naturally colonized by many pathogen species that can further limit its expansion.

From autopoiesis to self-optimization: Toward an enactive model of biological regulation

The theory of autopoiesis has been influential in many areas of theoretical biology, especially in the fields of artificial life and origins of life. However, it has not managed to productively connect with mainstream biology, partly for theoretical reasons, but arguably mainly because deriving specific working hypotheses has been challenging. The theory has recently undergone significant conceptual development in the enactive approach to life and mind. Hidden complexity in the original conception of autopoiesis has been explicated in the service of other operationalizable concepts related to self-individuation: precariousness, adaptivity, and agency. Here we advance these developments by highlighting the interplay of these concepts with considerations from thermodynamics: reversibility, irreversibility, and path-dependence. We interpret this interplay in terms of the self-optimization model, and present modeling results that illustrate how these minimal conditions enable a system to re-organize itself such that it tends toward coordinated constraint satisfaction at the system level. Although the model is still very abstract, these results point in a direction where the enactive approach could productively connect with cell biology.

A not-glycosylated isoform of γ-conglutin, a hexameric glycoprotein of Lupinus albus seed, participates in the oligomerization equilibrium

γ-conglutin (γ-C) is a hexameric glycoprotein accumulated in lupin seeds and has long been considered as a storage protein. Recently, it has been investigated for its possible postprandial glycaemic regulating action in human nutrition and for its physiological role in plant defence. The quaternary structure of γ-C results from the assembly of six monomers in reversible pH-dependent association/dissociation equilibrium. Our working hypothesis was that the γ-C hexamer is made up of glycosylated subunits in association with not-glycosylated isoforms, that seem to have ‘escaped’ the correct glycosylation process in the Golgi. Here we describe the isolation of not-glycosylated γ-C monomers in native condition by two in tandem lectin-based affinity chromatography and the characterization of their oligomerization capacity. We report, for the first time, the observation that a plant multimeric protein may be formed by identical polypeptide chains that have undergone different post-translational modifications. All obtained considered, the results strongly suggest that the not-glycosylated isoform can also take part in the oligomerization equilibrium of the protein.

Декларированные и латентные социальные группы: феномен, эволюция, детерминанты. Часть 2

The aim of the research is to study the features of the social environment as potential conditions for the formation, functioning and evolution of latent social groups. Hypotheses: 1) there are pre-forms of social alliances of people (which can be tentatively called latent social groups); 2) different conditions of a subject’s external and internal environment (including features perceived by a person as subjectively significant for them in relation to certain life goals) might be the reasons why the pre-forms appear. The methods of the research are as follows: theoretical and categorical analysis, the study of literary sources, empirical research (questionnaires), multidimensional methods of parametric statistics. According to the author’s methodology (questionnaire “Dynamics of professional life style” – DPLS), respondents assessed the following variables: the role conditions of the social environment play as “factors of professionalism”, and the dynamics of their professionalism from 20 to 65 years (retrospectively to the current age and prospectively – predicting the dynamics of subsequent evolution); their socio-demographic and official characteristics were also recorded. 482 employees, men and women aged 30 to 50 years (132 civil servants, 129 engineers and heads of departments of manufacturing plants, 221 managers) were interviewed as participants of the study. The total sample was divided into groups several times. As criteria for division, relative characteristics (calculated by the formulas) of “career speed”, “managerial experience”, “family life experience” were used. The results of the empirical study confirm the working hypotheses. When dividing the sample according to different criteria – both obvious (men / women, specialists / managers, etc.) and relative, the groups differ significantly in a number of variables (environmental conditions marked as “factors of professionalism”). Conclusion: in one social space-time, different social alliances, structures, to a greater or lesser extent of their expression (manifestation), development, and active functioning as social groups can coexist. There are reasons to single out the phenomenon of latent social groups (LSG) as pre-forms of manifest social groups with subsequent different trajectories of their possible development. LSG are possible alliances of people who are similar to each other in a number of important aspects of life (value orientations, lifestyle, etc.), and who are potentially capable of integration and interaction (to achieve common goals, to establish comfortable interpersonal communication, to maintain typical patterns of behavior, etc.). LGS are the pre-stages of various social structures representing their possible formation and development. Representatives of some latent social groups differ from others both in terms of their preference and recognition of the role of individual environmental conditions and individual social spaces (parental family, their family, work groups, etc.). There may be some other “deep factors” behind people’s recognition of the subjective significance of different conditions of the social environment for them.

The DTX Protein Family: An Emerging Set of E3 Ubiquitin Ligases in Cancer.

Until recently, Deltex (DTX) proteins have been considered putative E3 ligases, based on the presence of an E3 RING domain in their protein coding sequence. The human DTX family includes DTX1, DTX2, DTX3, DTX3L and DTX4. Despite the fact that our knowledge of this class of E3-ubiquitin ligases is still at an early stage, our understanding of their role in oncogenesis is beginning to unfold. In fact, recently published studies allow us to define specific biological scenarios and further consolidate evidence-based working hypotheses. According to the current evidence, all DTX family members are involved in the regulation of Notch signaling, suggesting a phylogenetically conserved role in the regulation of this pathway. Indeed, additional evidence reveals a wider involvement of these proteins in other signaling complexes and cancer-promoting mechanisms beyond NOTCH signaling. DTX3, in particular, had been known to express two isoform variants (DTX3a and DTX3b). The recent identification and cloning of a third isoform variant in cancer (DTX3c), and its specific involvement in EphB4 degradation in cancer cells, sheds further light on this group of proteins and their specific role in cancer. Herein, we review the cumulative knowledge of this family of E3 Ubiquitin ligases with a specific focus on the potential oncogenic role of DTX isoforms in light of the rapidly expanding findings regarding this protein family's cellular targets and regulated signaling pathways. Furthermore, using a comparative and bioinformatic approach, we here disclose a new putative motif of a member of this family which may help in understanding the biological and contextual differences between the members of these proteins.

Electroencephalography-Derived Functional Connectivity in Sensorimotor Networks in Post Stroke Fatigue

BackgroundPoor suppression of anticipated sensory information from muscle contractions is thought to underlie high fatigue. Such diminished task-related sensory attenuation is reflected in resting state connectivity. Here we test the hypothesis ‘altered electroencephalography (EEG)-derived functional connectivity in somatosensory network in the beta band, is a signature of fatigue in post-stroke fatigue’.MethodsIn non-depressed, minimally impaired stroke survivors (n = 29), with median disease duration of 5 years, resting state neuronal activity was measured using 64-channel EEG. Graph theory-based network analysis measure of functional connectivity via small-world index (SW) was calculated focusing on right and left motor (Brodmann areas 4, 6, 8, 9, 24 and 32) and sensory (Brodmann areas 1, 2, 3, 5, 7, 40 and 43) networks, in the beta (13–30 Hz) frequency range. Fatigue was measured using Fatigue Severity Scale - FSS (Stroke), with scores of > 4, defined as high fatigue.ResultsResults confirmed the working hypothesis, with high fatigue stroke survivors showing higher small-worldness in the somatosensory networks when compared to low fatigue.ConclusionHigh levels of small-worldness in somatosensory networks indicates altered processing of somesthetic input. Such altered processing would explain high effort perception within the sensory attenuation model of fatigue.

Drafting the Bibliotheke . Diodorus Siculus’ Writing Process

Summary The article offers a new perspective on the organization of Diodorus Siculus’ process of writing the Bibliotheke Historike. By analyzing passage 1.4.6 and fragment 40.8 in terms of both the vocabulary used and their function within the narrative, the article argues for the interpretation that Diodorus created an extended draft of his work (hypothesis) before dividing it into individual books. This interpretation is further strengthened by the analysis of the compositional features of the Bibliotheke. The analysis of the distribution of material between the books suggests that Diodorus in general had a very good idea about the amount of space he needed for different periods. At the same time, the presence of the unfulfilled declarations concerning the missing material suggests that the division has been made before the work has been brought to completion. Proposed interpretation is also congruent with what we know about the ancient authors’ writing process. The article argues that the final division into books, taking place after the unauthorized publication of some books referred to in 40.8, constituted a defining point for the Bibliotheke as we know it. Such a perspective opens various possibilities, e.g. that after making the final division, Diodorus was no longer constrained to work in chronological order. It also opens a possibility that the Bibliotheke was not as close to being finished as it is usually assumed.

Presence of Non-Tuberculous Mycobacteria Including Mycobacterium avium subsp. paratuberculosis Associated with Environmental Amoebae.

One of the obstacles to eradicating paratuberculosis or Johne's Disease (JD) seems to be the persistence of Mycobacterium avium subsp. paratuberculosis (Map) in the environment due to its ability to survive alone or vectorized. It has been shown that Map is widely distributed in soils and water. Previously, we isolated amoebae associated with Map strains in the environment of bovines from an infected herd. This work aims to verify our working hypothesis, which suggests that amoebae may play a role in the transmission of JD. In this study, we sampled water in the vicinity of herds infected with Map or Mycobacterium bovis (M. bovis) and searched for amoebae and mycobacteria. Live amoebae were recovered from all samples. Among these amoebae, four isolates associated with the presence of mycobacteria were identified and characterized. Map and other mycobacterial species were detected by qPCR and, in some cases, by culture. This study suggests that amoebae and Map may be found in the same environment and might represent a risk of exposure of animals to pathogenic mycobacteria. These data open up new perspectives on the control measures to be put in place to prevent contamination by Map.

The paradox of learned song in a semi‐solitary mammal

AbstractLearning can occur via trial and error; however, learning from conspecifics is faster and more efficient. Social animals can easily learn from conspecifics, but how do less social species learn? In particular, birds provide astonishing examples of social learning of vocalizations, while vocal learning from conspecifics is much less understood in mammals. We present a hypothesis aimed at solving an apparent paradox: how can harbor seals (Phoca vitulina) learn their song when their whole lives are marked by loose conspecific social contact? Harbor seal pups are raised individually by their mostly silent mothers. Pups' first few weeks of life show developed vocal plasticity; these weeks are followed by relatively silent years until sexually mature individuals start singing. How can this rather solitary life lead to a learned song? Why do pups display vocal plasticity at a few weeks of age, when this is apparently not needed? Our hypothesis addresses these questions and tries to explain how vocal learning fits into the natural history of harbor seals, and potentially other less social mammals. We suggest that harbor seals learn during a sensitive period within puppyhood, where they are exposed to adult males singing. In particular, we hypothesize that, to make this learning possible, the following happens concurrently: (1) mothers give birth right before male singing starts, (2) pups enter a sensitive learning phase around weaning time, which (3) coincides with their foraging expeditions at sea which, (4) in turn, coincide with the peak singing activity of adult males. In other words, harbor seals show vocal learning as pups so they can acquire elements of their future song from adults, and solitary adults can sing because they have acquired these elements as pups. We review the available evidence and suggest that pups learn adult vocalizations because they are born exactly at the right time to eavesdrop on singing adults. We conclude by advancing empirical predictions and testable hypotheses for future work.