Friedrich-Ebert-Stiftung e.V.

The incorporation of the natural photosynthetic apparatus into a (soft matter) environment highly restricts the number of degradation possibilities and furthermore enables targeted repair of key molecular components. Intrigued by this design-principle of the natural blueprint, we postulate that balancing the interplay between polymeric matrices and photocatalytically active centers prolongs and sustains photocatalytic activity as well as repair-capability in molecular artificial photosynthesis. There are few systems where active repair has been demonstrated, and one prominent example is the Ru(tpphz)PtI2 hydrogen-evolving photocatalyst, where hydrogenation of the pyrazine ring in the tpphz bridging ligand has been shown to lead to an end of photocatalytic activity. Subsequent in-situ repair by persulfate enabled catalyst reactivation, but so far at the cost of decreasing catalytic activity over several repair cycles. We now show that tailored polyampholytic graft copolymers allow to electrostatically immobilize the photocatalyst in a unimolecular soft matter matrix, can prolong (photo)catalytic activity, and facilitate active repair without significant loss of activity over several cycles. We attribute this to a decreased propensity for hydrogenation of the pyrazine ring and, with that, slower degradation of the bridge and improved long term HER activity, as evidenced by a holistic spectroscopic characterization of molecular and electronic structure of the photoredox catalyst. We therefore regard this as a novel blueprint for a synergistic molecule-in-matrix combination for sustainable light-driven catalysis.

Rising summer temperatures are increasing the demand for shading solutions and indoor cooling technologies. Given the substantial surface area of gable roofs, their effective shading plays a significant role in thermal management. While modern buildings often feature heat-insulated roofs equipped with photovoltaic panels or infrared-reflective coatings, such measures are frequently unsuitable for traditional, particularly heritage-protected structures. For this specific category of buildings, ventilated infrared (IR) shielding elements installed on the underside of rafters offer a promising approach to reduce surface temperatures and limit radiative heat transfer to attics or upper living spaces. This study evaluates performance-optimized IR shading systems for heritage roofs, focusing on material selection and emissivity effects. Results indicate that ventilated OSB panels with low-emissivity coatings achieve up to 53% thermal load reduction compared to unshielded conditions. Ventilation of the rafter fields emerges as the critical factor for the functional performance of such IR shading elements.

A review of valid species within genus Pygmaeconus Puillandre & Tenorio, 2017, is presented. Combined analysis of molecular [partial mitochondrial cytochrome c oxidase subunit I (cox1) gene sequences of several individuals, and a nearly-complete mitogenome for one individual] and morphological (shell and radular tooth) characters revealed that tiny cone snails collected with algae and shell grit by scuba at 12 m depth in the southeastern Philippines correspond to a new species, introduced here under the name Pygmaeconus atomus sp. nov. It attains a maximum adult size of < 5 mm, being arguably the smallest recorded member of the cone-snail fauna worldwide.

Through their innovations, the IT and software sectors are part of new emerging technologies which are fundamentally changing other cultural and creative industries (CCIs). As countries must catch up with them to develop their creative economies, the authors of this paper have performed empirical research on the national software innovation ecosystem, which included 242 IT companies from Serbia in 2022. Regression analysis and the Likert scale were used to assess the influence of three groups of factors of the e-innovation ecosystem: institutional, business, and internal factors. The key results of the research show the impact of all these factors, the most significant being that of institutional factors and public policies and measures. The results of this paper could contribute to the design of innovation-based policies, supporting an environment that would promote the creative IT economy in Serbia.

Aus Uganda wird die neue Art Caenis longilobata sp. n. anhand von Männchen beschrieben. Melanistische Exemplare von Caenis aus Uganda werden der bereits aus Uganda bekannten Caenis jinjana Kimmins, 1956 zugeordnet, deren ursprüngliche Beschreibung ergänzt wird.

Human immunodeficiency virus type 1 (HIV-1)-neutralizing antibodies (nAbs) that prevent infection are the main goal of HIV vaccine discovery. But as no nAb-eliciting vaccines are yet available, only data from HIV-1 neutralizers—persons with HIV-1 who naturally develop broad and potent nAbs—can inform about the dynamics and durability of nAb responses in humans, knowledge which is crucial for the design of future HIV-1 vaccine regimens. To address this, we assessed HIV-1-neutralizing immunoglobulin G (IgG) from 2,354 persons with HIV-1 on or off antiretroviral therapy (ART). Infection with non-clade B viruses, CD4+ T cell counts <200 µl−1, being off ART and a longer time off ART were independent predictors of a more potent and broad neutralization. In longitudinal analyses, we found nAb half-lives of 9.3 and 16.9 years in individuals with no- or low-level viremia, respectively, and 4.0 years in persons who newly initiated ART. Finally, in a potent HIV-1 neutralizer, we identified lower fractions of serum nAbs and of nAb-encoding memory B cells after ART initiation, suggesting that a decreasing neutralizing serum activity after antigen withdrawal is due to lower levels of nAbs. These results collectively show that HIV-1-neutralizing responses can persist for several years, even at low antigen levels, suggesting that an HIV-1 vaccine may elicit a durable nAb response.

The expansion of renewable energies requires implementing Smart Grid Services (SGSs) in the distribution grid. Analytical verification of the SGSs’ Quality of Service (QoS) requirements is crucial for reliable operation. This paper proposes a two-step approach: a constraint satisfaction problem (CSP) considers network infrastructure and resource allocations to find candidates’ solutions. Then, the solutions are evaluated using Network Calculus (NC) to calculate delay bounds at the worst-case and compare them to the requirements. If necessary, alternative solutions are generated. The NC framework is adjustable and considers different service priorities by implementing scheduling policies such as strict priority, weighted fair queuing, weighted round robin, and deficit round robin. In the end, the best-performing parameters are derived for a sample network and the results manifest that the NC framework can be used to analyze random communication networks.