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Transporting or blending hydrogen (H2) into the existing gas infrastructure can be crucial in the European green transition. However, the regulation of this matter is still debated by interested stakeholders. The THOTH2 project aims to fill normative gaps by developing new protocols for assessing the limits and tolerances of state-of-the-art (SoA) instrumentation installed in natural gas (NG) transmission and distribution grids. This paper outlines the methodology used for selecting the devices and establishing the testing protocols for the various categories of instruments. These instruments are scheduled for experimental testing in the subsequent phase of the project.

The rapidly developing quantum communication technology requires deterministic quantum emitters that can generate single photons and entangled photon pairs in the third telecom window, in order to be compatible with existing optical fiber networks and on-chip silicon photonic processors. InAs/InP quantum dots (QDs) are among the leading candidates for this purpose, due to their high emission efficiency in the required spectral range. However, fabricating versatile InAs/InP QD-based quantum emitters is challenging, especially as these QDs typically have asymmetric profiles in the growth plane, resulting in a substantial bright-exciton fine structure splitting (FSS). This hinders the generation of entangled photon pairs and thus, compromises the versatility of InAs/InP QDs. We overcome this by implementing droplet epitaxy (DE) synthesis of low surface density (2.8 × 108cm−2) InAsxP1−xQDs with x= (80 ± 15)% on an (001)-oriented InP substrate. The resulting QDs are located in etched pits, have concave bases, and most importantly, have symmetric in-plane profiles. We provide an analytical model to explain the kinetics of pit formation and QD base shape modification. Our theoretical calculations of electronic states reveal the properties of neutral and charged excitons and biexcitons confined in such QDs, which agree with the optical investigations of individual QDs. The optical response of QDs' ensemble suggests that FSS may indeed be negligible, as reflected in the vanishing degree of linear polarization. However, single QD spectrum gathered from an etched mesa shows moderate FSS of (50 ± 5) µeV that we link to destructive changes made in the QD environment during the post-growth processing. Finally, we show that the studied DE QDs provide a close-to-ideal single-photon emission purity of (92.5 ± 7.5)% in the third telecom window.

ABSTRACTTools for machining are exposed to high loads, wear, and elevated temperatures. Commonly, such tools consist of cemented carbides and tool steel. To combine the advantages of both materials, high-quality-joints with high strengths are desired. When brazing these materials, the main challenge is the mismatch of the Coefficient of Thermal Expansion (CTE) and the poor wettability of cemented carbides by molten filler alloys. In this regard, the feasibility of two custom-made alloys (CuNi12Si5, CuNi12Si5B0.4) was analysed. Besides being a cost-efficient alternative, these alloys offer the possibility to modify their mechanical properties by precipitation hardening to reduce stresses within the final joints. Thus, this paper shows that a temperature of 1060°C is suitable for wetting and brazing tests on different substrates.

Tools for machining are exposed to high loads, wear, and elevated temperatures. Commonly, such tools consist of cemented carbides and tool steel. To combine the advantages of both materials, high-quality-joints with high strengths are desired. When brazing these materials, the main challenge is the mismatch of the Coefficient of Thermal Expansion (CTE) and the poor wettability of cemented carbides by molten filler alloys. In this regard, the feasibility of two custom-made alloys (CuNi12Si5, CuNi12Si5B0.4) was analysed. Besides being a cost-efficient alternative, these alloys offer the possibility to modify their mechanical properties by precipitation hardening to reduce stresses within the final joints. Thus, this paper shows that a temperature of 1060°C is suitable for wetting and brazing tests on different substrates.

The aim of the experiment was to study the brain's response to the sound stimuli at a specific frequency. The relation between the specific sounds and the changes in the electrical activity of the brain, caused by it, may be helpful to develop the treatment methods of the various disorders of the brain, using the sounds. The aim of the experiment described in the article is to determine the changes in the signal spectrum during the sounds performance with different parameters and to relate it to the basic rhythms, occurring in the EEG signal.

This article presents a subset of findings on the experience of bone marrow aspiration and biopsy (BMAB) from an Australian hematology survivorship study.

This article presents the findings of a cross-cultural research project that explored similarities and differences between palliative care service provision in Kerala, India and South-East Queensland, Australia, to inform a process of mutual learning for service development.Three major points of difference that can inform this process of mutual learning were identified: 1) an understanding of the significance of honesty in information-giving to the patient, 2) recognition of the importance of palliative care specialists providing education to mainstream health professionals, and 3) appreciation of the need for palliative care to be cognizant of the socio-economic impact of dying-especially for families experiencing poverty-by embracing strategies for financial and material support. The findings highlight the effectiveness of a cross-cultural collaboration between health professionals and researchers in South-East Queensland, Australia and Kerala, India.

In recent years the literature on bioethics has begun to pose the sociological challenge of how to explore organisational processes that facilitate a systemic response to ethical concerns. The present discussion seeks to make a contribution to this important new direction in ethical research by presenting findings from an Australian pilot study. The research was initiated by the Clinical Ethics Committee of Redland Hospital at Bayside Health Service District in Queensland, Australia, and explores health professionals’ understanding of the nature of ethics and their experience with ethical decision-making within an acute medical ward. This study focuses on the actual experience, understanding and attitudes of clinical professionals in a general medical ward. In particular, the discussion explores the specific findings from the study concerned with how a multi-disciplinary team of health professionals define and operationalise the notion of ethics in an acute ward hospital setting. The key issue reported is that health professionals are not only able to clearly articulate notions of ethics, but that the notions expressed by a multi-disciplinary diversity of participants share a common definitional concept of ethics as patient-centred care. The central finding is that all professional groups indicated that there is a guiding principle to address their ethical sense of the ‘good’ or the ‘ought’ and that is to act in a way that furthered the interests of patients and their families. The findings affirm the importance of a sociological perspective as a productive new direction in bioethical research.

AbstractAlthough the incidence of cancer in Indigenous peoples is similar to its incidence in the overall Australian population, Indigenous peoples are less likely to access early detection and medical interventions resulting in higher mortality and morbidity rates. To explore and address this discrepancy, the National Health and Medical Research Council funded a research study to examine Indigenous peoples’ views of cancer and cancer treatments with an end goal of developing an innovative model of Indigenous Palliative Care. Seventy-two participants were interviewed from four geographical areas within the Northern Territory (Australia) including patients, caregivers, Indigenous and non-Indigenous health care workers, and interpreters. Indigenous peoples’ views of cancer have to be examined within a historical, socio-political, and cultural context. There is no Indigenous word for cancer and the Western biomedical language that semantically constructs the notion of cancer is not widely understood. Additionally, for many Indigenous people, the aetiology of cancer is embedded in beliefs about the spiritual world of curses and payback from perceived misdeeds. The paper advocates for cross-cultural education initiatives, stressing the importance of a two way education strategy incorporating a process whereby medical and nursing personnel would improve their understanding of Indigenous peoples’ view of cancer and Indigenous peoples would learn more about prevention and treatment of cancer from a biomedical perspective.

Objectives: To explore communication issues faced by health care workers and Indigenous patients and their families in a palliative care setting. Effective communication with Aborigines is especially important because Aboriginal beliefs of health and sickness are so different from Western views. Method: Data were collected from 72 qualitative interviews conducted throughout the regional, rural and remote areas of the Northern Territory with Indigenous patients and carers and the health professionals who care for them. Results: Participants highlighted the struggle associated with effective communication when working in a cross-cultural setting at the interface of Indigenous and Western health care. The findings record the wisdom and insight from practitioners who have extensive experience dealing with communication difficulties.

The transcription factor hepatocyte nuclear factor 4 (HNF4) is an orphan member of the nuclear receptor superfamily expressed in mammals in liver, kidney, and the digestive tract. Recently, we isolated the Xenopushomolog of mammalian HNF4 and revealed that it is not only a tissue-specific transcription factor but also a maternal component of the Xenopusegg and distributed within an animal-to-vegetal gradient. We speculate that this gradient cooperates with the vegetally localized embryonic induction factor activin A to activate expression of HNF1α, a tissue-specific transcription factor with an expression pattern overlapping that of HNF4. We have now identified a second Xenopus HNF4gene, which is more distantly related to mammalian HNF4than the previously isolated gene. This new gene was named HNF4β to distinguish it from the known HNF4gene, which is now called HNF4α. By reverse transcription-PCR, we detected within the 5′ untranslated region of HNF4β two splice variants (HNF4β2 and HNF4β3) with additional exons, which seem to affect RNA stability. HNF4β is a functional transcription factor acting sequence specifically on HNF4 binding sites known for HNF4α, but it seems to have a lower DNA binding activity and is a weaker transactivator than the α isoform. Furthermore, the two factors differ with respect to tissue distribution in adult frogs: whereas HNF4α is expressed in liver and kidney, HNF4β is expressed in addition in stomach, intestine, lung, ovary, and testis. Both factors are maternal proteins and present at constant levels throughout embryogenesis. However, using reverse transcription-PCR, we found the RNA levels to change substantially: whereas HNF4α is expressed early during oogenesis and is absent in the egg, HNF4β is first detected in the latest stage of oogenesis, and transcripts are present in the egg and early cleavage stages. Furthermore, zygotic HNF4α transcripts appear in early gastrula and accumulate during further embryogenesis, whereas HNF4β mRNA transiently appears during gastrulation before it accumulates again at the tail bud stage. All of these distinct characteristics of the newly identified HNF4 protein imply that the α and β isoform have different functions in development and in adult tissues.

The gene encoding the tissue-specific transcription factor HNF1alpha (LFB1) is transcriptionally activated shortly after mid-blastula transition in Xenopus embryos. We have now shown that the HNF1alpha protein is localized in the nuclei of the liver, gall bladder, gut and pronephros of the developing larvae. In animal cap explants treated with activin A together with retinoic acid, we induced HNF1alpha in pronephric tubules and epithelial gut cells, i.e. in mesodermal as well as in endodermal tissues. HNF1alpha can also be induced by activin A, but not by retinoic acid alone. To define the promoter element responding to the activin A signal, we injected various HNF1alpha promoter luciferase constructs into fertilized eggs and cultured the isolated animal caps in the presence of activin A. From the activity profiles of the promoter mutants used, we identified the HNF4-binding site as an activin-A-responsive element. As HNF4 is a maternal protein in Xenopus and localized in an animal-to-vegetal gradient in the cleaving embryo, we speculate that the activin A signal emanating from the vegetal pole cooperates with the maternal transcription factor HNF4 to define the embryonic regions expressing HNF1alpha.

LFB1 (HNF1) is a tissue-specific transcription factor found in the livers, stomachs, intestines, and kidneys of vertebrates. By analyzing the promoter of the Xenopus LFB1 gene, we identified potential autoregulation by LFB1 and regulation by HNF4, a transcription factor with a tissue distribution similar to that of LFB1. Injection of LFB1 promoter-chloramphenicol acetyltransferase constructs into Xenopus eggs revealed embryonic activation that is restricted to the region of the developing larvae expressing endogeneous LFB1. Proper embryonic activation was also observed with a rat LFB1 promoter. Deletion analysis of the Xenopus and rat promoters revealed that in both promoters embryonic activation is absolutely dependnet on the presence of an element that contains CCNCTCTC as the core consensus sequence. Since this element is recognized by the maternal factor OZ-1 previously described by N. Ovsenek, A. M. Zorn, and P. A. Krieg (Development 115:649-655, 1992), we might have identified the main constituents of a hierarchy that leads via LFB1 to the activation of tissue-specific genes during embryogenesis.

The gene encoding the tissue-specific transcription factor HNF1α (LFB1) is transcriptionally activated shortly after mid-blastula transition in Xenopus embryos. We have now shown that the HNF1α protein is localized in the nuclei of the liver, gall bladder, gut and pronephros of the developing larvae. In animal cap explants treated with activin A together with retinoic acid, we induced HNF1α in pronephric tubules and epithelial gut cells, i.e. in mesodermal as well as in endodermal tissues. HNF1α can also be induced by activin A, but not by retinoic acid alone. To define the promoter element responding to the activin A signal, we injected various HNF1α promoter luciferase constructs into fertilized eggs and cultured the isolated animal caps in the presence of activin A. From the activity profiles of the promoter mutants used, we identified the HNF4-binding site as an activin-A-responsive element. As HNF4 is a maternal protein in Xenopus and localized in an animal-to-vegetal gradient in the cleaving embryo, we speculate that the activin A signal emanating from the vegetal pole cooperates with the maternal transcription factor HNF4 to define the embryonic regions expressing HNF1α.

The transcription factor hepatocyte nuclear factor 4 (HNF4) is an orphan member of the nuclear receptor superfamily expressed in mammals in liver, kidney, and the digestive tract. Recently, we isolated the Xenopus homolog of mammalian HNF4 and revealed that it is not only a tissue-specific transcription factor but also a maternal component of the Xenopus egg and distributed within an animal-to-vegetal gradient. We speculate that this gradient cooperates with the vegetally localized embryonic induction factor activin A to activate expression of HNF1alpha, a tissue-specific transcription factor with an expression pattern overlapping that of HNF4. We have now identified a second Xenopus HNF4 gene, which is more distantly related to mammalian HNF4 than the previously isolated gene. This new gene was named HNF4beta to distinguish it from the known HNF4 gene, which is now called HNF4alpha. By reverse transcription-PCR, we detected within the 5' untranslated region of HNF4beta two splice variants (HNF4beta2 and HNF4beta3) with additional exons, which seem to affect RNA stability. HNF4beta is a functional transcription factor acting sequence specifically on HNF4 binding sites known for HNF4alpha, but it seems to have a lower DNA binding activity and is a weaker transactivator than the alpha isoform. Furthermore, the two factors differ with respect to tissue distribution in adult frogs: whereas HNF4alpha is expressed in liver and kidney, HNF4beta is expressed in addition in stomach, intestine, lung, ovary, and testis. Both factors are maternal proteins and present at constant levels throughout embryogenesis. However, using reverse transcription-PCR, we found the RNA levels to change substantially: whereas HNF4alpha is expressed early during oogenesis and is absent in the egg, HNF4beta is first detected in the latest stage of oogenesis, and transcripts are present in the egg and early cleavage stages. Furthermore, zygotic HNF4alpha transcripts appear in early gastrula and accumulate during further embryogenesis, whereas HNF4beta mRNA transiently appears during gastrulation before it accumulates again at the tail bud stage. All of these distinct characteristics of the newly identified HNF4 protein imply that the alpha and beta isoform have different functions in development and in adult tissues.

Hepatocyte nuclear factor 4 (HNF4) was first identified as a DNA binding activity in rat liver nuclear extracts. Protein purification had then led to the cDNA cloning of rat HNF4, which was found to be an orphan member of the nuclear receptor superfamily. Binding sites for this factor were identified in many tissue-specifically expressed genes, and the protein was found to be essential for early embryonic development in the mouse. We have now isolated cDNAs encoding the human homolog of the rat and mouse HNF4 splice variant HNF4 alpha 2, as well as a previously unknown splice variant of this protein, which we called HNF alpha 4. More importantly, we also cloned a novel HNF4 subtype (HNF4 gamma) derived from a different gene and showed that the genes encoding HNF 4 alpha and HNF4 gamma are located on human chromosomes 20 and 8, respectively. Northern (RNA) blot analysis revealed that HNF4 GAMMA is expressed in the kidney, pancreas, small intestine, testis, and colon but not in the liver, while HNF4 alpha RNA was found in all of these tissues. By cotransfection experiments in C2 and HeLa cells, we showed that HNF4 gamma is significantly less active than HNF4 alpha 2 and that the novel HNF4 alpha splice variant HNF4 alpha 4 has no detectable transactivation potential. Therefore, the differential expression of distinct HNF4 proteins may play a key role in the differential transcriptional regulation of HNF4-dependent genes.

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