Recent digital developments provide new opportunities for entrepreneurs to market and present themselves. For solo entrepreneurs, where the business and entrepreneur coincide, self-presentation strategies on social media may be particularly relevant. Using regression analysis, we investigate the personal and business-related characteristics of solo entrepreneurs who typically rely heavily on social media for self-presentation. Data are used from a unique survey conducted among solo entrepreneurs in Austria. At the conceptual level, the impression management theory of Goffman from the 1950s creates the theoretical background, and our paper links three fields of research: social media use, impression management, and aspects relating to solo self-employment. The empirical analysis reveals that the typical solo entrepreneur who attaches great importance to social media use for self-presentation purposes is a female entrepreneur running a young business (younger than 5 years) in the retail industry, with good mental health but relatively poor financial health.

Recently, there have been discussions about the shape of the heliopause. Some scientists question the classical form, which is close to a paraboloid. They suggest that the heliopause may have a two-jet collimated shape. While we disagree with this view of the heliopause shape, it seems likely that for stars with stronger stellar magnetic fields and those that are at rest or moving slowly through the interstellar medium, the astropause will have a two-jet collimated shape. This paper raises the question of the stability of the two-jet collimated astrosphere. Recent studies have noted the emergence of instability in the heliosheath near the axis of the heliospheric jets, linking this to the action of neutral hydrogen atoms. We note in this paper that astrospheric jets can become unstable in the presence of strong magnetic fields, even without the influence of atoms, which is unexpected. Furthermore, due to a feedback mechanism, astrospheric jets undergo self-oscillation. We investigated the development of this instability, the nature of the feedback mechanism, and the period of self-oscillation for different system parameters. Our findings provide valuable insights into the behaviour of these unique plasma structures, and they are another step towards studying the stability of two-jet collimated astrospheres.

The alfalfa weevil Hypera postica Gyllenhal (Coleoptera: Curculionidae) is one of the most destructive alfalfa pests in the world, resulting in substantial economic losses. However, the amount of damage can be reduced by larval parasitoids of the genus Bathyplectes Förster (Hymenoptera: Ichneumonidae) as a conservation biological control strategy. Parasitoids are currently identified by morphological body characteristics, cocoon morphology, and/or DNA analysis, but geometric morphometrics (GM) applied to the wing vein arrangement may also reveal differences between specimens. We distinguished 61 B. anurus (Thomson) and 41 B. curculionis (Thomson) specimens, based on the appearance of the cocoon. GM revealed statistically significant differences in wing vein patterns and fore wing shapes between species, but not between sexes within the same species. The 1 M + 1R1 cell, also known as the horsehead cell, was revealed to be an easy and reliable morphological character for species differentiation. Despite the New World literature, this is the first European report providing a visual method to differentiate B. anurus from B. curculionis. This study highlights the importance of precise species identification methods, such as geometric morphometry. It can contribute to a better implementation of biological control strategies against the alfalfa weevil in Spain and other Mediterranean countries.

Finger weeders were first developed in the 1950s and have since been widely adopted by farmers to improve physical weed control (PWC) within crop rows. Research on finger weeders has largely been comparative, with most studies identifying a top-performing weed control practice among various physical or chemical treatments. Weeding tool performance, however, is often highly variable, affected by tool design and adjustment, soil conditions, and both weed and crop species and size. Finger weeder operating settings have not been systematically tested to determine whether they could optimize tool performance. In this project, field and soil bin experiments examined the effects of finger weeder angle, spacing, and speed on weed control efficacy and weed/crop selectivity. Three finger weeder angles were tested: 108°, which removed soil near the crop; 90°, typical for most commercial tools; and 68°, which moved soil into the crop row. Three spacings and speeds were compared: fingers overlapping (−0.6 cm), touching (0 cm), or spaced apart (2.5 cm); and 4, 7, and 9 km h−1. In both the field and soil bin, finger weeders set at a 68° angle resulted in the greatest efficacy. Decreasing finger spacing and increasing speed improved efficacy in soil bin experiments, as expected, but spacing and speed effects were not detected in the field. The experimental soil bin system shows promise for PWC testing, possibly offering insights that could not be detected in more variable field conditions.

In this work, we demonstrate the generation of high-performance tunable Raman solitons beyond 3 μm in a 10 cm, large-core (40 μm) fluorotellurite fiber. The pump source is a high-peak-power Raman soliton generated through soliton fission in a silica fiber. By further cascading the 10 cm highly nonlinear fluorotellurite fiber, this Raman soliton undergoes successive high-order soliton fission and soliton self-frequency shift with a tunable range of 2.7–3.3 μm. Such an ultra-short-length and ultra-large-core fiber significantly reduces the pulse width of the 3.3 μm Raman soliton to 55 fs, doubling the peak power to 2.3 MW compared to previous studies. Furthermore, owing to the seed’s high-repetition-frequency feature, the 3.3 μm Raman soliton’s power exceeds 2 W. These performance metrics represent the highest levels achieved for Raman solitons at wavelengths above 3 μm, offering a simple and effective new approach for generating high-peak-power femtosecond pulses in the mid-infrared spectral region.

Given a symmetric monoidal category ${\mathcal C}$ with product $\sqcup $, where the neutral element for the product is an initial object, we consider the poset of $\sqcup $-complemented subobjects of a given object X. When this poset has finite height, we define decompositions and partial decompositions of X which are coherent with $\sqcup $, and order them by refinement. From these posets, we define complexes of frames and partial bases, augmented Bergman complexes and related ordered versions. We propose a unified approach to the study of their combinatorics and homotopy type, establishing various properties and relations between them. Via explicit homotopy formulas, we will be able to transfer structural properties, such as Cohen-Macaulayness.

In well-studied scenarios, the poset of $\sqcup $-complemented subobjects specializes to the poset of free factors of a free group, the subspace poset of a vector space, the poset of nondegenerate subspaces of a vector space with a nondegenerate form, and the lattice of flats of a matroid. The decomposition and partial decomposition posets, the complex of frames and partial bases together with the ordered versions, either coincide with well-known structures, generalize them, or yield new interesting objects. In these particular cases, we provide new results along with open questions and conjectures.

To sustain a protracted war after losing foreign loans and reserves and being sanctioned by the Allies, Japan used its ‘internal financing mechanism’ to gobble up civilian capital through government bonds, unbacked paper currency and interest rate interventions. These tactics aggrandised the size of the monetary base and money supply in Japan’s home islands and colonies, but also created inflationary pressures. To minimise the risk of (hyper)inflation, the government encouraged civilians to save in order to enrich the capital of financial intermediaries who would then absorb the ever-increasing government bonds. The ideal failed as monetary expansion outstripped economic productivity, even though expansionary monetary policy had to be tolerable in order to supply sufficient credit for war production. Imperial Japan’s use of unsecured credit to finance the war, together with its loose exchange controls, led to the diversion of colonial hyperinflationary pressures to the home islands, multiplying the risk of implosion of the ‘internal financing mechanism’. Although draconian currency controls were subsequently introduced, they further disrupted the empire’s economic order, and eventually led to the collapse of the yen bloc.

Heart failure in children is a clinical and pathophysiological syndrome arising from ventricular dysfunction and pressure or volume overload of the circulatory system. Features of paediatric heart failure include feeding problems, poor weight gain, exercise intolerance, or dyspnoea. The aetiology of heart failure in children is complex, with the primary causes being CHD and cardiomyopathies. Cardiomyopathies occur at an incidence of 1.13–1.24 cases per 100,000 children. The prevalence of cardiomyopathy is estimated to be 7.8–8.3 cases per 100,000 infants, particularly common in patients under one year of age presenting with severe heart failure symptoms. Mitral valve insufficiency is a significant source of morbidity in children with dilated cardiomyopathy. Severe mitral insufficiency can lead to a decrease in cardiac output, independent of the left ventricular ejection fraction, exacerbating the clinical course of heart failure in patients with dilated cardiomyopathy. As ventricular systolic function deteriorates, the options for treating mitral insufficiency decrease, leading to a loss of surgical intervention opportunities and making heart transplantation the only viable option. Close monitoring of mitral valve insufficiency in children with dilated cardiomyopathy is essential, as it may lead to decompensated heart failure. In patients who have lost the chance for valve surgery due to decompensation, the application of left ventricular assist device can help improve the decompensatory state and contribute to the reduction of left ventricular diastolic and systolic dimensions, consequently leading to improvements in the dilation of the mitral annulus and severe mitral insufficiency findings. Further studies are needed to determine the optimal timing for surgery in patients who have not missed the chance for valve surgery due to a decrease in ejection fraction.

In recent years, analysts have raised concerns about the threat misinformation poses to democracy, yet efforts to counter misinformation have been met with charges of bias and censorship, predominantly from the political right. This article asks who sets the terms of debate over misinformation: what it is, how much there is, whether it is a problem, and what to do about it. It frames the past decade’s controversies around misinformation as an implicit struggle for authority and offers a framework to interpret the arguments of the actors involved. It identifies three coalitions with distinct institutional and ideological profiles that have articulated consistent stances on misinformation. The analysis demonstrates how contestation among competing coalitions plays out in five distinct domains of misinformation: content, attribution, scale, consequences, and policy. Viewing the misinformation debate as part of broader political and cultural struggles within democracies at a time of low trust in institutions helps explain why (mis)information is so fiercely contested. The issue takes on outsize proportions because whoever prevails in shaping the discourse surrounding misinformation stands to gain authority over the rules governing the public sphere, with implications for the future of free speech and democratic participation.