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Aims: We aim to evaluate the effectiveness of the Integrated Palliative Care Outcome Scale for people with dementia-based case studies to improve the caring quality for people with dementia in nursing homes by frontline staff and family members. Background: Swiss nursing homes mostly care for people with dementia. This population is at high risk of receiving little to no palliation for their complex needs. The majority of Swiss frontline healthcare staff do not systematically report on the needs of their residents. Additionally, family members do not routinely participate in assessment processes. Design We will conduct a stepped-wedge cluster randomized trial of repeated assessment using the Integrated Palliative Care Outcome Scale for people with dementia (IPOS-Dem) and subsequent case studies. Clusters will consist of Swiss nursing homes randomly assigned to one of three sequential intervention time points. Methods: The study population will consist of people with dementia living in nursing homes with and without specialized dementia care facilities. Over 16 months, staff working at the frontline and family members will assess the needs and concerns of people with dementia using IPOS-Dem. Depending on sequence allocation, facilitated case studies will start after 3, 6 or 9 months. The primary outcome will be caring quality measured by QUALIDEM. The secondary outcome will be symptoms and concerns, as indicated by the IPOS-Dem sum-score. The Zürich Ethics Committee approved the study in 2019 (2019-01847). Impact: The results of this study will contribute to improving the effectiveness of person-centred care for people with dementia. Collaboration between healthcare staff and family members will be systematically developed and built upon thorough assessment using the IPOS-Dem and related case studies. The use of IPOS-Dem will offer all frontline staff a systematic approach to have an independent voice within the nursing process, regardless of their qualification or grade.

We report on solution-processed, semitransparent organic solar cells that are implemented as lenses in sunglasses. The electrical power provided by the lens-fitted solar cells sustains a microelectronic circuit that is used to read out temperature and illumination intensity sensors and to make this information available on two displays integrated into the temples of the “Solar Glasses”. The microelectronic circuit is designed to operate at illumination intensities down to 500 lux, rendering the Solar Glasses suitable for outdoor and indoor use as well as for operation in diffuse light. Hence, this case study provides an example for consumer-oriented mobile applications, self-powered by integrated solar cells, which specifically exploit the unique properties of organic solar cells.

Das Auftreten von Lackfilmstorungen durch Pustelbildung stellt in der industriellen Praxis der Pulverbeschichtung verzinkter Stahlbauteile ein wirtschaftliches Problem dar. Mit einer Reihe sich erganzender wissenschaftlicher Methoden wurden die verursachenden Reagenzien und Entstehungsmechanismen der Pustelbildung erforscht und eine durchgangige Theorie der Pustelbildung entwickelt. Dabei kamen die metallografische Mikroskopie und Analytik ebenso zum Einsatz, wie nasschemische Untersuchungsmethoden, die Glimmentladungsspektroskopie und die Massenspektrometrie. Eine massenspektrometrische Detektion der aus dem Zinkuberzug ausstromenden Gase zeigte, dass mit einem Volumenanteil von 82% insbesondere Wasser, gefolgt von 10% Kohlendioxid und 8% Wasserstoff fur die Pustelbildung verantwortlich zu machen sind. The occurrence of defects like pustules in varnish finishings results in economic problems in the industrial practice of powder coating of galvanized steel parts. The mechanism for the formation of pustules was investigated in a set of scientific integrating methods and a general theory was developed. Metallographic microscopy with its analytic tools as well as wet chemistry research were applied, further glow discharge spectroscopy (GDOS) and mass spectrometry. With mass spectrometry the outgassings from a hot dip zinc probe were identified: it is mainly water with 82% by volume, followed by carbon dioxide (10%) and hydrogen (8%), which together are responsible for the formation of the pustules.

Metropol Parasol ist ein architektonisch und stadtebaulich innovatives und kontrovers diskutiertes Projekt inmitten der Altstadt von Sevilla, das eine archaologische Ausgrabungsstatte, eine Markthalle, einen stadtischen Open-Air-Veranstaltungsort und eine spektakulare Verschattungskonstruktion aus Holz mit integriertem Restaurant und Aussichtswegen, alles vertikal ubereinander gestapelt, vereint. Der Artikel beschreibt den Tragwerksentwurf im Zusammenspiel mit den formalen und funktionalen Aspekten des Projekts. Die disparaten Anforderungen an das Tragwerk fuhrten zur beschriebenen Hybridkonstruktion aus Holz, Beton, Stahl und Stahlverbund. Dieser Aufsatz beschreibt den gesamten Tragwerksentwurf und Teile seiner Umsetzung in Beton, Stahl und Stahlverbund sowie das Brandschutzkonzept. Ein weiterer Artikel in dieser Ausgabe geht ausfuhrlicher auf die innovative Holzkonstruktion ein. Metropol Parasol in Seville – Innovative hybrid structure in timber, concrete and steel. Metropol Parasol is an urbanistic and architecturally innovative and much discussed signature project in the centre of the old town of Seville. It comprises an archaeological site, a market hall, an urban open-air venue space and a spectacular shading structure which is manufactured from timber and includes a restaurant and walkways on the top. This paper describes the structural design and it’s interdependency with the formal and functional aspects of the project. The disparate requirements for the structural design were best met with a hybrid structure of timber, concrete, steel and steel composite. This paper describes the structural design of the entire project and parts of the concrete, steel and steel composite structure as well as the fire engineering. Another article in this issue will explain in detail the innovative timber structure.

Der aus Sicht der Tragwerksplaner interessanteste und auch fur die Besucher spektakularste Teil des Projekts Metropol Parasol ist die 150 m lange und bis zu 28 m hohe, begehbare Holzkonstruktion aus mehrlagig verklebten Furnierschichtholzscheiben. Die Realisierung gelang nur dank einiger konstruktiver Innovationen, wie der 2 bis 3 mm dicken Polyurethan-Beschichtung, montageoptimierten Verbindungsdetails und der weltweit erstmals im Holzbau eingesetzten Temperung des fur das Einkleben der Gewindestangen verwendeten Epoxid-Harzes. Auserdem erlautert der Bericht besondere Fragestellungen zur statischen Berechnung, der Herstellung und der Montage. New concepts in timber structures with LVL plates – The timber structure of Metropol Parasol in Seville. The most impressive part of the Metropol Parasol from a structural engineer’s point of view as well as from the visitor’s perspective is the 150 m long and up to 28 m high timber structure of the parasols made of multi-glued laminated veneer lumber (LVL) panels. Realisation succeeded due to several constructive innovations like 2–3 mm thick polyurethane coating, easy to install node details and the world premiere of tempered epoxy resin for glued-in rods in a timber construction. Beyond this, the article elucidates special questions concerning the structural design, production and assembly.

Eine Hochtemperaturbrennstoffzelle (solid oxide fuel cell = SOFC) hat zwar ein sehr einfaches Funktionsprinzip, jedoch erfordern die sehr unterschiedlichen Materialien der Einzelkomponenten hochentwickelte thermische Fugeverfahren, um sie funktionsgerecht miteinander zu verbinden. Fur die SOFC existieren zwei Optionen einer moglichen Anwendung, erstens als dezentrale Hauskraftwerke (stationare SOFC), zweitens als Energiewandler fur Kraftfahrzeuge (mobile SOFC). Es haben sich daher im Forschungszentrum Julich zwei sehr verschiedene Konstruktionstypen etabliert, fur die auch die Entwicklung unterschiedlicher Verfahren zum Fugen der Einzelkomponenten erforderlich wurde. Beim stationaren Design besteht der Hauptfugeprozess in dem elektrisch isolierenden Verbinden einzelner Stahlplatten durch ein Glaslot zu einem SOFC-Stapel. Beim mobilen Design besteht der SOFC-Stapel aus einzelnen dunnen Stahlkassetten. Bei den Kassetten wird deren Fensterblech aus ferritischem Chromstahl mit der keramischen Schicht des Zirkonoxidfeststoffelektrolyten durch ein metallisches Lot verlotet. Es handelt sich bei diesem Lot um ein Silberbasislot mit nur geringen benetzungsbegunstigenden Zusatzen von Kupferoxid und Titanhydrid. Entscheidend fur beide Lotprozesse ist ihre Anwendbarkeit in normaler Atmosphare (Luft), also unter oxidativen Bedingungen. Um die SOFC zur Marktreife auf dem Energiesektor zu entwickeln, dauern die F&E-Arbeiten zur Wirkungsgradsteigerung und zur Langzeitbetriebsstabilitat an. Auch die beiden Lotverfahren sind noch nicht als normale Standardprozesse zu betrachten, sondern erfordern ebenso permanente Weiterentwicklungen, hier im Hinblick auf Reproduzierbarkeit, Bestandigkeit und Festigkeit der Lotverbunde. Auf der Suche nach geeigneten schnellen Ersatzmethoden, um die Fugeeigenschaften der Lotmaterialien genauer studieren und messtechnisch erfassen zu konnen, ohne den Bau aufwendiger komplexer SOFC-Stacks betreiben zu mussen, setzt die Arbeitsgruppe Sonderfugetechnik im Forschungszentrum Julich speziell abgewandte dilatometrische Messverfahren ein. Mit einem sog. Absenkdilatometer werden die Schwindungsprozesse der Glaslotfugen nachgestellt und im μm-Bereich gemessen. Dies ermoglicht, die fur Dichtheit und Kontaktierung entscheidende Glaslotmenge und die Prozessparameter vorherzubestimmen. Mit einem vertikalen Dilatometer erfolgen Untersuchungen des Schmelzverhaltens der reaktiven Silberlote im Hinblick auf Schmelzpunktverschiebung, Zahigkeit und Porenanteil und in Abhangigkeit von der Prozessatmosphare und von einem metallischen Additiv (Aluminium). The principle of operation of solid oxide fuel cells (SOFCs) is very simple. However, the fact that very different materials are used for the individual components requires advanced thermal joining techniques to join them in a functional manner. Two very distinct designs have established themselves for the two different intended applications: decentralised power generation (stationary SOFCs) on the one hand, and power converters for vehicles (mobile SOFCs) on the other hand. As a consequence, alternative techniques for joining the individual components are also required. The principal joining process for the stationary SOFC design consists of joining individual steel plates with a glass sealant in an electrically insulating way so that they form an SOFC stack. For the mobile fuel cell design, the SOFC stack consists of individual thin steel cassettes. The window frame of the cassettes, which is made of ferritic chromium steel, is brazed to the ceramic layer of the zirconium oxide solid electrolyte using a filler metal. The material used is a silver-based brazing filler metal which contains only small amounts of copper oxide (CuO) and titanium hydride (TiH2) as wetting agents. Both joining processes must be applicable in normal atmospheric air, i. e. under oxidative conditions. R&D activities continue for improving the efficiency and long-term operational stability of the technology to such an extent that SOFCs will become ready for the energy sector market. The two joining techniques described cannot yet be considered standard processes. They, too, will require continuous improvement with respect to reproducibility, endurance and strength of the joints. The Special Joining Techniques working group at Forschungszentrum Julich uses specially modified dilatometric techniques as suitable quick replacement methods for studying and measuring the joining characteristics of the materials without having to manufacture complex and expensive SOFC stacks. The shrinkage processes in the glass sealant joints are simulated and measured in the μm range using a special dilatometer. In this way, the amount of glass sealant – which is decisive for tightness and bonding – and the process parameters can be determined in advance. With a vertical dilatometer, the melting behaviour of the reactive silver filler metals is examined with respect to melting point shift, viscosity and void ratio, and as a function of the metal additives (Al) and the process atmosphere.

A series of liquid crystalline compounds based on 2,7-bis(biphenyl)fluorenes was synthesised by a Suzuki cross-coupling reaction and subsequent etherification with different bromoalkenes. By simple variations of the chain lengths the temperature range in which the nematic mesophase is present could be tuned. The described approach offers the possibility of covalent incorporation of the mesogens into polymers via olefin metathesis techniques, resulting in enlarged stability of the mesophase. Monomers and polymers could be easily aligned on rubbed polyimide substrates as revealed by polarised absorption spectroscopy.

Three new strains of eukaryotic picoplankton, isolated from Lake Baikal, were identified as Nannochloropsis limnetica Krienitz, Hepperle, Stich & Weiler. To date, N. limnetica had only been detected in small German and North American inland water bodies. On determination of the 18S rDNA sequence, the three new strains were found to be identical to each other and to the type strain KR 1998/3 (GenBank accession no. AF251496). Rapid analysis of polymorphic DNA-PCR revealed that the genotypes were different, although the Baikalian eustigmatophycean strains were more similar to each other compared with the type strain KR 1998/3 from Germany. Ecophysiological differences were also evident between the new strains from Lake Baikal and the type strain from growth rate determinations. The morphological characteristics were similar to that of a previous description of the species. However, although the cells of Eustigmatophyceae usually propagate by autosporulation, in these newly detected species germination of single daughter cells from thick-walled cells was observed for the first time. Based on pigment analysis, the occurrence of Eustigmatophyceae in Lake Baikal was estimated. Eustigmatophyceae were established to be common members of the phytoplankton community of this large oligotrophic Siberian lake and occurred throughout the year, even under the ice cover during winter. Moreover, they peaked during early summer and in the South Basin. Hence, the widely accepted opinion that Chlorophyceae solely comprise the eukaryotic picoplankton should be changed and the Eustigmatophyceae considered.

The aim of the present study was to investigate the effects of melatonin on non-adrenergic, non-cholinergic (NANC) relaxant neurotransmission in the gastrointestinal tract, which is mainly mediated by nitrergic and peptidergic mechanisms. Melatonin (10(-7)-10(-3) M) had no effect on the basal tonus of the rat gastric fundus smooth muscle. Relaxant responses following electrical stimulation(40 V; 0.5 ms pulse duration; 10 s stimulation duration) under NANC conditions on a 5-hydroxytryptamine (5-HT, 10(-7) M) contraction plateau were elicited at frequencies in the range of 0.5-16 Hz. Melatonin significantly reduced these inhibitory NANC responses (16 Hz without melatonin: -103 +/- 6.3%; melatonin 10(-5) M: -80.4 +/- 7.5%; melatonin 10(-4) M: -39.1 +/- 17.1%). Intracellular recording was carried out in a mouse colonic preparation. Electrical neural stimulation of the mouse colonic neurons caused biphasic intracellular hyperpolarization in smooth-muscle cells. The initial fast component is apamin-sensitive, and the following slow component is dependent on nitrergic mechanisms, as it is abolished in the presence of NG-nitro-L-arginine (L-NNA). Melatonin significantly reduced the nitric oxide-dependent slow component of neurally transmitted hyperpolarization, whereas the initial fast component was left unchanged. In a synaptosomal preparation of the enteric nervous system of rat intestine, enzymatic nitric oxide synthase (NOS) activity was significantly reduced by melatonin at concentrations ranging from 10(-7) to 10(-4) M (basal preparation including cofactors: 61.2 +/- 9.4 fmol/mg; melatonin 10(-4) M: 39.2 +/- 6.9 fmol/mg). Reverse transcriptase-polymerase chain reaction (RT-PCR) studies were conducted to investigate the melatonin receptors (mt(1), MT(2) and MT(3)) present in the esophagus, stomach and ileum of the rat. The presence of mt1 mRNA expression alone, but not of mRNA expression for MT(2) or MT(3), was demonstrated in the tissues. In conclusion, this study demonstrates that melatonin reduces the functional inhibitory NANC response. It shows that this effect may be the result of a reduction of the nitrergic component of the smooth-muscle inhibitory junction potential (IJP) and related to direct inhibition of NOS activity in enteric synaptosomes. The presence of mt1 receptor transcripts adds supportive evidence for a possible physiological role of melatonin within the enteric nervous system.

It has been proposed that the membrane allows a much more efficient binding of certain small or medium-sized amphiphilic messenger molecules to their receptor, not only by accumulation of the drug, but also by induction of orientations and conformations that are much more favorable for receptor docking than structures adopted in isotropic phases. A series of eight amphiphilic cyclic peptides containing lipophilic (L-α-aminodecanoic acid=Ada, L-α-aminohexadecanoic acid=Ahd, Nhdg=N-hexadecylglycine) and hydrophilic (Lys, Asp) amino acids were synthesized and examined by means of NMR spectroscopy and molecular dynamics (MD) simulations in isotropic (CDCl3) and membrane-mimicking anisotropic (SDS/H2O) solvents to study the influence of the environment on their individual conformations. NMR data of cyclo(-Gly1-D-Asp2-Ahd3-Ahd4-Asp5-Gly6-) (C4), cyclo(-Lys1-D-Pro2-Lys3-Ada4-Pro5-Ada6-) (C5) and cyclo(-Lys1-Pro2-Lys3-Ada4-D-Pro5-Ada6-) (C6) clearly indicate that those compounds are too rigid to perform a conformational change upon transition from an isotropic to an anisotropic environment. On the other hand, the experimental data of cyclo(-Gly1-Asp2-Ahd3-Ahd4-Asp5-Gly6-) (C1), cyclo(-Asp1-Ala2-Nhdg3-Ala4-D-Asp5-) (C7), and cyclo(-D-Asp1-Ala2-Nhdg3-Ala4-Asp5-) (C8) suggest highly flexible unstructured molecules in both environments. However, for cyclo(-Asp1-Asp2-Gly3-Ahd4-Ahd5-Gly6-) (C2) we observed a structure inducing effect of a membrane-like environment. The compound populates three different conformations in SDS/H2O, whereas in CDCl3 no preferred conformation can be detected. cyclo(-D-Asp1-Asp2-Gly3-Ahd4-Ahd5-Gly6-) (C3) clearly exhibits two different conformations with a shifted β,β-turn motif in CDCl3and SDS/H2O solutions. The conformational change could be reproduced in a restraint-free MD simulation using the biphasic membrane mimetic CCl4/H2O. Our results give clear evidence that membrane interactions may not only lead to structure inductions, but can also induce major conformational changes in compounds already exhibiting a defined structure in isotropic solution. Copyright © 1999 European Peptide Society and John Wiley & Sons, Ltd.

Aims and objectives The aim of this integrative literature review was twofold: (1) to investigate different collaborative programmes for older people with depression living at home with diverse access to care and (2) to describe conceptualisation of the nurses' role and interventions within these care models. Background One in four older people who visits a General Practitioner suffers from depression. Depression is a concern for 15% of all older home-care service clients. Detecting and managing depression in older people is highlighted as a key role of nurses. A literature review has been conducted to investigate collaborative models of care, aimed at ensuring low-threshold access to care and exploring the scope of nurse practice within these models. Methods Literature review comprising 14 studies and reviews. Results Three different collaborative care programmes (Collaborative Care Model, Community Mental Health Team and Psychogeriatric Assessment and Treatment in City Housing programme) were identified. In all programmes, the essential aspects were complex and multifaceted interventions, provided by a variety of healthcare professionals, but the access to care differed. All studies described the role of nurses differently and with wide variations. Conclusions Despite a broad scope of practice, nurses play a pivotal role within the different models of care. Nurses have to have the educational background and expertise in mental health issues to recognise depression and eventually be able to provide more comprehensive interventions to alleviate depression in older people. Relevance to practice Collaboration is needed to meet the needs of older people with depression. New forms of work divisions are pivotal to achieve this objective.

The αv/β3 integrin is implicated in human tumor metastasis and angiogenesis. It has been shown that structures of the sequence cyclo(-Arg1-Gly2-Asp3-D-Phe4-Xaa5-) (I) and cyclo(-Arg1-Gly2-Asp3-Phe4-D-Xaa5-) (II) bind with high affinity and the latter with high selectivity to this receptor. The residues Xaa and D-Xaa accept a broad variety of amino acids. Here, we report on the synthesis, activities, and conformational analysis of cyclic Arg-Gly-Asp (RGD) peptides containing liophilic amino acids Xaa or D-Xaa in position 5. For I, these were (2S)-2-aminohexadecanoic acid (Ahd) and N′-hexadecylglycine (Hd-Gly) and in II, D-Ahd and Hd-Gly, and, for control purposes, Ahd were incorporated (Fig. 1). The enantiomerically pure a-amino acids were obtained by non-enantioselective synthesis and subsequent enzymatic separation of isomers using acylase I (Scheme). Hd-Gly was prepared in a modified procedure according to Stewart from ethyl bromoacetate and hexadecylamine (Scheme). The synthesis and physicochemical properties of the corresponding (9H-fluoren-9-ylmethoxy)carbonyl (Fmoc) derivatives, compatible with solid-phase peptide synthesis, are described. Structure elucidation by NMR reveals that the lipid modification has no significant impact on the template structures when incorporated into them. For peptides I with Xaa = Ahd or Hd-Gly (1 or 2), a βII′/γ-turn-like arrangement with D-Phe in i+1 position of the β-turn is found. Peptides II with D-Xaa = D-Ahd or Hd-Gly (3 or 4) exhibit a βII′/γ-turn conformation with Gly in i+1 position of the β-turn, whereas II with Ahd instead of D-Xaa, i.e., lacking a D-amino acid in position 4 or 5 (5). adopts no defined conformation. However, in assays of receptor specificity employing human αvv/β3 integrin, the compounds exhibit IC50 values ranging from nanomolar to less than millimolar. These results indicate that although the arrangement of the pharmacophoric groups is preserved in the target compounds, the biological activity is highly dependent on spatial requirements of the lipid anchor in the receptor binding pocket. Obviously, only certain positions do not affect the binding.

Various sites of Phragmites australis in Germany (Uckermark and Mark Brandenburg) and sites in Hungary and Denmark were investigated by PCR fingerprinting in order to determine their genetic diversity. Genetic similarities were calculated and, based on this, a cluster analysis was performed. The genetic similarity of reed clones around one lake ranged from between 70 to 100%, that of clones from different lakes was clearly lower. The further apart the clones were situated from each other, the less similar they were. At a wetland site near the shore a sudden colonisation by several new Phragmites clones was observed. This site was located in front of a well established genetically almost homogenous stand within the eulittoral. All the results are discussed in connection with a proposed model of establishment and development of water reed stands: colonization, selection of best adapted clones by competition and the stability of stands.

The amino-terminal fragment of human uPA (ATF; amino acids 1-135), which contains the binding site for the uPA receptor (uPAR, CD87) was expressed in the yeast Saccharomyces cerevisiae. Recombinant yeast ATF, modified and extended by an amino-terminal in-frame insertion of a His6 tract, was purified from total protein extracts by nickel chelate affinity chromatography and shown to be functionally active since it efficiently competes with uPA for binding to cell-surface-associated uPAR. The ATF expression plasmid served as a template for the construction of a series of site-directed mutants in order to define those amino acids that are important for binding to uPAR. All mutant ATF proteins but one (deletion of Ser26) were expressed in a stable form (about 20-30 ng/mg total protein) and the binding capacity of each mutant was tested by a uPA-ligand binding assay employing recombinant uPAR immobilized to a microtiter plate. Each of the 11 amino acids of loop B of the binding region of uPA (amino acids 20-30) were individually substituted with alanine. Lys23, Tyr24, Phe25, IIe28, and Trp30 were important determinants for uPAR binding. A systematic alanine scan was also performed with chemically synthesized linear peptides spanning amino acids 14-32 of ATF. Comparable results to those with the yeast ATF mutants were obtained. In a different set of experiments, those amino acids of the uPAR-binding region of uPA that are only conserved between man and baboon but not in other species were altered: whereas substitution of Thr18 by alanine or Asn32 by serine had hardly any effect, replacement of Asn22 by tyrosine and Trp30 by arginine (both positions are strictly conserved in other mammals) led to ATF variants incapable of interacting with human uPAR. Deletion of either Val20, Ser21, Lys23, His29 or Val20 plus Ser21, respectively, also generated non-reactive ATF mutants. Finally, Lys23 in ATF was substituted with certain amino acids: whereas the replacement of Lys23 by alanine, histidine or glutamine generated ATF variants with moderate uPAR-binding activity, the introduction of a negatively charged amino acid (exchange of Lys23 by glutamic acid) completely abolished uPAR-binding activity. The results presented for the ATF mutants and uPA-derived peptides may provide clues necessary to establish the nature of the physical interaction of uPA with its receptor and may help to develop uPA-derived peptide analogues as potential therapeutic agents to block tumor cell-associated uPA/uPAR interaction.

All-solution deposited, ITO-free organic solar cells comprising hybrid top and bottom electrodes and ternary polymer:fullerene photo-active layers are investigated. A printed micro silver mesh and conductive PEDOT:PSS are employed as bottom electrode on a mechanically flexible PET substrate, whereas the top electrode features highly conductive PEDOT:PSS with dispersed silver nanowires. The highly efficient ternary polymer:fullerene absorber blend PffBT4T-2OD:PC61BM:PC71BM and all other functional layers are doctor bladed from non-halogenated solvents in order to comply with the requirements of industrial device fabrication. The semi-transparent solar cells yield maximum power conversion efficiencies of 6.6% on active areas ≤ 0.1 cm2 and 5.9% on active areas > 1 cm2. Omitting additional bus bars for charge extraction grants the solar cells a homogeneous appearance and transparency perception.

A fundamental analysis of the external quantum efficiency (EQE) of organic tandem solar cells with equal absorbers in both subcells (homo-tandem solar cells) is presented. Providing direct access to both subcells by introducing a conductive intermediate polymer electrode into the recombination zone, without changing the optical and electric device properties, the three-terminal device becomes a proxy to the two-terminal tandem solar cell properties. From the spectrally resolved EQE of the subcells in three-terminal configuration wavelength and intensity of suitable bias light as well as bias voltage are determined that in turn allow for accurate EQE measurements of the common two-terminal tandem solar cells. Theoretic considerations allow the prediction of the tandem solar cell's EQE from its subcells' EQEs as well as the prediction of the tandem cell EQE under monochromatic bias light illumination being in excellent agreement with experimental results. All findings discussed herein can be applied to more common hetero-tandem solar cell architectures likewise.