Intergenerational resource sharing and mortality in a global perspective

Resource sharing has always been a central component of human sociality. Children require heavy investments in human capital; during working years, help is needed due to illness, disability, or bad luck. While hunter-gatherer elders assisted their descendants, more recently, elderly withdraw from work and require assistance as well. Willingness to share has been critically important for our past evolutionary success and our present daily lives. Here, we document a strong linear relationship between the public and private sharing generosity of a society and the average length of life of its members. Our findings from 34 countries on six continents suggest that survival is higher in societies that provide more support and care for one another. We suggest that this support reduces mortality by meeting urgent material needs, but also that sharing generosity may reflect the strength of social connectedness, which itself benefits human health and wellbeing and indirectly raises survival

Fluid inclusions in speleothems as a new archive for the noble gas palaeothermometer

Fluid inclusions in speleothem constitute a unique archive for palaeo-waters. This thesis deals with the investigation of fluid inclusions in speleothems and their possible use as a palaeotemperature archive. The main objective focuses on the calculation of noble gas temperatures, which can be derived from the temperature-dependent solubility of the noble gases He, Ne, Ar, Kr and Xe. An essential requirement is the determination of noble gas concentrations, which implies measuring the absolute gas amounts as well as determining the amounts of water released. Two ways of measuring the tiny water amounts (≤ 1 μl) extracted from the speleothems are presented and will be discussed with regard to the required precision. Furthermore, various techniques for the extraction of noble gases from the speleothems are investigated and analysed in terms of the intended application. It turned out that crushing under vacuum in a steel cylinder by milling with a magnetically movable steel ball is the most suitable technique. Additionally, the noble gas preparation and the mass spectrometric procedure, optimized for the measurement of tiny gas amounts, will be discussed. Finally, it is demonstrated that it is possible to determine reliable temperatures from fluid inclusions in speleothems and that the acquired results can be reproduced to a certain extent. From the stalagmite BU-U (Sauerland, NW Germany) six samples from one growth period were extracted and measured. Their results agree within the uncertainties although the samples are not totally identical. Measurements on other stalagmites (BU-1, BU-2) from the same cave revealed temperatures corresponding to the expected climatic conditions in the respective growth period. Typical uncertainties for these samples range from ≤ 1 ℃ to 2 ℃ at most. From the stalagmites BU-U and BU-1 a temperature record has been established by noble gas concentrations and will be discussed in combination with the stable isotope data. These exemplary applications reveal the high potential of the method presented

Oxygen and clumped isotope fractionation during the formation of Mg calcite via an amorphous precursor

The oxygen and clumped isotope signatures of Mg calcites are routinely used as environmental proxies in a broad range of surroundings, where Mg calcite forms either by classical nucleation or via an amorphous calcium magnesium carbonate (ACMC) precursor. Although the (trans)formation of ACMC to Mg calcite has been identified for an increasing number of settings, the behavior of both isotope proxies throughout this stage is still unexplored. In the present study ACMC (trans)formation experiments were carried out at constant pH (8.30 ± 0.03) and temperature (25.00 ± 0.03 °C) to yield high Mg calcite (up to 20 mol% Mg). The experimental data indicate that the oxygen isotope values of the amorphous and/or crystalline precipitate (δ$^{18}$O$_{prec}$, analyzed as Mg calcite) are affected by the (trans)formation pathway, whereas clumped isotopes (Δ$_{47prec}$ = Δ$_{47Mg-calcite}$) are not. The oxygen isotope evolution of the solid phase can be explained by the instantaneous trapping of the isotopic composition of the aqueous (bi)carbonate complexes. This entrapment results in remarkably high 10$^{3}$ln(α$_{prec-H2O}$) values of ∼33‰ at the initial ACMC formation stage. During the ACMC transformation process the oxygen isotope equilibrium is approached rapidly between Mg calcite and water (Δ$^{18}$O$_{Mg calcite-water}$ = 30.3 ± 0.4‰) and no isotopic memory of the initial to the final Mg calcite at the end of the experiment occurs. The implications for oxygen and clumped isotope signatures of Mg calcite formed via ACMC are discussed in the aspects of various scenarios of (trans)formation conditions and their use as environmental proxies

Online at Will: A Novel Protocol for Mutual Authentication in Peer-to-Peer Networks for Patient-Centered Health Care Information Systems

Patient-centered health care information systems (PHSs) on peer-to-peer (P2P) networks promise decentralization benefits. P2P PHSs, such as decentralized personal health records or interoperable Covid-19 proximity trackers, can enhance data sovereignty and resilience to single points of failure, but the openness of P2P networks introduces new security issues. We propose a novel, simple, and secure mutual authentication protocol that supports offline access, leverages independent and stateless encryption services, and enables patients and medical professionals to establish secure connections when using P2P PHSs. Our protocol includes a virtual smart card (software-based) feature to ease integration of authentication features of emerging national health-IT infrastructures. The security evaluation shows that our protocol resists most online and offline threats while exhibiting performance comparable to traditional, albeit less secure, password-based authentication methods. Our protocol serves as foundation for the design and implementation of P2P PHSs that will make use of P2P PHSs more secure and trustworthy

Herausforderungen und Chancen für die Lithiumgewinnung aus geothermalen Systemen in Deutschland – Teil 1: Literaturvergleich bestehender Extraktionstechnologien

Die hier vorgestellte Arbeit schätzt den Stand der Extraktionstechnologien zur Lithiumgewinnung aus geothermalen Wässern basierend auf aktuellen wissenschaftlichen Studien ab und identifiziert mögliche technische Herausforderungen. Bewertet werden häufig diskutierte Technologien wie Flüssig-Flüssig-Extraktion, selektive Extraktion durch anorganische Sorptionsmittel, elektrochemische Methoden und Membrantechnologien hinsichtlich ihrer Anwendbarkeit und Integrierbarkeit in die geothermische Energieproduktion. Aktuelle Forschungsprojekte haben verschiedene Extraktionsmethoden im Labor- und teilweise Prototypenmaßstab validiert. Eine Skalierung zu einem industriellen Prozess existiert bisher nicht. Dementsprechend fehlen Informationen bezüglich Dauerbetrieb sowie dem Einfluss standortspezifischer Hürden (Wasserchemie, Volumenstrom, Fließraten, etc.) und zur tatsächlichen Wirtschaftlichkeit. Die Menge des rückgewinnbaren Lithiums ergibt sich in erster Linie aus der Konzentration des im Wasser gelösten Lithiums, der Extraktionseffizienz und –geschwindigkeit, sowie der Menge des verwendeten Extraktionsmittels. Das Zusammenspiel dieser Faktoren bestimmt die Verfahrenstechnik und die Größe der Extraktionsinfrastruktur. Je nach Verfahren werden die physikochemischen Eigenschaften des Wassers (pH, Eh, T, p, etc.) während der Extraktion verändert, wodurch das Scaling- und Korrosionspotential gesteigert werden kann

Herausforderungen und Chancen für die Lithiumgewinnung aus geothermalen Systemen in Deutschland – Teil 2: Potenziale und Produktionsszenarien in Deutschland

Die hier vorgestellte Arbeit liefert Hintergrundinformationen, um das Potential einer künftigen Lithiumproduktion aus geothermalen Fluiden in Deutschland abzuschätzen. Aus der wachsenden Nachfrage und der bisherigen Abhängigkeit von schlecht diversifizierten Überseequellen lässt sich eine hohe strategische Bedeutung einer möglichen Binnenquelle ableiten. Hinzu kommen ökologische Aspekte, wie CO2-ärmere und flächenschonendere Lithiumgewinnungsmethoden. Basierend auf dem Technologievergleich zur direkten Lithiumextraktion aus geothermalen Fluiden und dem heutigen Ausbauzustand der Geothermie in Deutschland und dem französischen Teil des Oberrheingrabens wurden unterschiedliche Szenarien für die extrahierbare Menge an Lithiumkarbonat berechnet. So lässt sich im optimistischsten Szenario unter Berücksichtigung aller zurzeit aktiven Bohrungen eine maximale Produktion von 7200 t/a Lithiumkarbonat-Äquivalent prognostizieren. Damit könnten 5 – 19 % des jährlichen Bedarfs der geplanten deutschen Batteriezellenproduktion gedeckt werden. Schlüsselparameter für das Prozessdesign sind der nutzbare Volumenanteil des geothermalen Fluids und die Extraktionseffizienz. Die Unsicherheiten in der Ressourcenbewertung bezüglich Größe und Nachhaltigkeit ihrer Bewirtschaftung sind bislang noch beachtlich. Um die großen Potentiale dieser Technologie nutzen zu können, müssen diese zentralen Fragen geklärt werden

Security Engineering of Patient-Centered Health Care Information Systems in Peer-to-Peer Environments: Systematic Review

Background: Patient-centered health care information systems (PHSs) enable patients to take control and become knowledgeable about their own health, preferably in a secure environment. Current and emerging PHSs use either a centralized database, peer-to-peer (P2P) technology, or distributed ledger technology for PHS deployment. The evolving COVID-19 decentralized Bluetooth-based tracing systems are examples of disease-centric P2P PHSs. Although using P2P technology for the provision of PHSs can be flexible, scalable, resilient to a single point of failure, and inexpensive for patients, the use of health information on P2P networks poses major security issues as users must manage information security largely by themselves. Objective: This study aims to identify the inherent security issues for PHS deployment in P2P networks and how they can be overcome. In addition, this study reviews different P2P architectures and proposes a suitable architecture for P2P PHS deployment. Methods: A systematic literature review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) reporting guidelines. Thematic analysis was used for data analysis. We searched the following databases: IEEE Digital Library, PubMed, Science Direct, ACM Digital Library, Scopus, and Semantic Scholar. The search was conducted on articles published between 2008 and 2020. The Common Vulnerability Scoring System was used as a guide for rating security issues. Results: Our findings are consolidated into 8 key security issues associated with PHS implementation and deployment on P2P networks and 7 factors promoting them. Moreover, we propose a suitable architecture for P2P PHSs and guidelines for the provision of PHSs while maintaining information security. Conclusions: Despite the clear advantages of P2P PHSs, the absence of centralized controls and inconsistent views of the network on some P2P systems have profound adverse impacts in terms of security. The security issues identified in this study need to be addressed to increase patients\u27 intention to use PHSs on P2P networks by making them safe to use

The interplay of incentives and mode-choice design in self-administered mixed-mode surveys

Self-administered mixed-mode surveys are increasingly used as an alternative to face-to-face surveys for collecting data from the general population. However, little is known about how decisions regarding the incentive scheme and the mode-choice design jointly affect key outcomes such as response rates, net sample composition, and survey costs. To study this, we drew a probability sample of the residential population of the city of Mannheim, Germany (N = 2,980) and randomly assigned target persons to one of four incentive schemes (€0, €1, or €2 prepaid incentive on first contact, and €2 delayed prepaid incentive) and one of two mode-choice designs (concurrent or sequential [web-push]). Our results indicate that small prepaid monetary incentives work better in concurrent than in sequential designs. Moreover, a €2 prepaid incentive in a concurrent design proved particularly successful for older target persons, probably reinforcing their sense of trust and reciprocity, while also fitting better with their survey-mode preferences. Finally, a €2 delayed prepaid incentive in a sequential design primarily motivated target persons aged under 50 years. This combination of incentive scheme and mode-choice design also proved to be most cost-effective in that age group. Based on our results, we recommend using sampling frame information on age to address different age groups with different combinations of incentive scheme and mode-choice design. This may help to maximize response rates, achieve a balanced net sample composition, and minimize survey costs