The Endoplasmic Reticulum Stress Response in Neuroprogressive Diseases: Emerging Pathophysiological Role and Translational Implications

The endoplasmic reticulum (ER) is the main cellular organelle involved in protein synthesis, assembly and secretion. Accumulating evidence shows that across several neurodegenerative and neuroprogressive diseases, ER stress ensues, which is accompanied by over-activation of the unfolded protein response (UPR). Although the UPR could initially serve adaptive purposes in conditions associated with higher cellular demands and after exposure to a range of pathophysiological insults, over time the UPR may become detrimental, thus contributing to neuroprogression. Herein, we propose that immune-inflammatory, neuro-oxidative, neuro-nitrosative, as well as mitochondrial pathways may reciprocally interact with aberrations in UPR pathways. Furthermore, ER stress may contribute to a deregulation in calcium homoeostasis. The common denominator of these pathways is a decrease in neuronal resilience, synaptic dysfunction and even cell death. This review also discusses how mechanisms related to ER stress could be explored as a source for novel therapeutic targets for neurodegenerative and neuroprogressive diseases. The design of randomised controlled trials testing compounds that target aberrant UPR-related pathways within the emerging framework of precision psychiatry is warranted

Reactive magnetron co sputtering of Cu In,Ga Se2 absorber layers by a 2 stage process Role of substrate type and Na doping

By simultaneous sputtering from metallic CuGa and In targets in an Ar H2Se atmosphere onto heated substrates, single phase and well crystallized Cu In,Ga Se2 thin films can be directly deposited in a single process step. However, the preparation of Cu poor films, which are needed for high solar cell efficiencies, is impeded by the re evaporation of excess indium, which occurs readily at moderate substrate temperatures in the range of 400 C to 500 C. Therefore, a significant In excess is necessary during the second deposition stage in order to transform the final film composition into the desired Cu poor regime [Cu] [In] [Ga] b 0.95 . Higher open circuit voltages and efficiencies are achieved for absorbers produced with an intermediate Cu rich composition and or by using Na containing precursor films NaF or Mo Na . A best cell efficiency of 12.9 is achieved, which demonstrates the high potential of the investigated reactive magnetron sputtering process for solar cell manufacturing, as it is well suited for large area, industrial application

Toward efficient Cu In,Ga Se2 solar cells prepared by reactive magnetron co sputtering from metallic targets in an Ar H2Se atmosphere

In this paper, we show that a reactive co sputtering process using metallic CuGa and In targets; an Ar H2Se atmosphere is well suited for the deposition of photoactive Cu In,Ga Se2 CIGSe absorber layers for thin film solar cells in a single process step. The achievement of single phase and well crystallized layers is thereby no major problem if a sufficiently high H2Se content and substrate temperatures in the range of 400 500 C are used. However, in order to achieve the desired Cupoor film stoichiometry, which is crucial for the device performance, it has to be considered already that, at moderate substrate temperatures in the range of 400 500 C, indium has a strong tendency to re evaporate from the film surface if the film composition is Cu poor. If excess indium is supplied, this effect can lead to a self adjustment of the film composition. This allows a very wide process window in a one stage process concerning the supply ratio from the two targets of [Cu] [In] [Ga] supply amp; 8776;0.35 0.8. However, the maximum efficiencies achievable with such a process are limited to 11.7 because an adequate Cu poor composition can only be achieved with significant Cu poor conditions, which allow only a low material quality. By using an improved process with an intermediate Cu rich composition and a final Cupoor stage, the absorber quality could be significantly improved; efficiencies of up to 14.3 have been achieved with CIGSe films prepared on Na doped Mo back contact

Ion energy distributions at a substrate in reactive magnetron sputtering discharges in Ar H2S from copper, indium and tungsten targets

Ion energy distributions from copper, indium and tungsten targets were measured during reactive sputtering in argon hydrogen sulfide H2S mixtures, since reactive magnetron sputtering of sulfides from metallic targets is of increasing interest, especially for photovoltaic applications buffer and absorber layers, i.e. CuInS2, In2S3 or WS2 . The mass spectra of the ions show a wide range of molecules HxSn derived from H2S by plasma assisted attachment, both for positive n amp; 8804;9 and negative n amp; 8804;6 ions. From the copper and the indium targets metallic ions Cu , In could be detected. While tungsten and indium sulfur compounds were found, copper does not form compounds with sulfur, caused by its lower chemical reactivity. Positive Ar , S , W , Cu , In etc. as well as negative ions S , InS , WS3 were measured for DC and RF 27 MHz plasma excitation. The positive ions originate mainly from the plasma in front of the substrate and exhibit energies of about 12 eV for the DC and 18 eV for the RF discharge for the substrate at floating potential. The energy difference is caused by the higher electron temperature in the RF compared to the DC discharge. The ion energy distributions of negative ions exhibit two distinct peaks. The high energetic peak can be attributed to ions accelerated in the cathode dark space to a high energy up to more than 400 eV corresponding to the cathode target voltage. The second peak has its maximum at zero energy decreasing steeply up to energies of about 100 eV. These ions are generated by charge exchange collisions of energetic species from the target reflected neutral argon, negative sulfur ions etc. on their passage from the target to the substrate caused by the high charge exchange cross section. RF magnetron sputtering leads to significantly lower energies of negative ions from the target, caused by the lower discharge voltages, which could be advantageous for the deposition of active semiconducting sulfide films. Keywords reactive magnetron sputtering, ion distribution functions, copper, indium, tungsten, sulfides, ion assisted growth, semiconductor thin films PACS numbers 52.40Hf, 52.70Nc, 73.61.Le, 81.15C

A combined sensor for the diagnostics of plasma and film properties in magnetron sputtering processes

A combined sensor for the simultaneous measurement of plasma and deposition parameters has been designed and built. It comprises i a quartz crystal microbalance, ii a planar Langmuir probe and iii a calorimetric Gardon probe, which allows to measure the deposition rate, typical plasma parameters plasma density and electron temperature and the total energy input into a growing film. The combined sensor is electrically insulated against ground, allowing these measurements also for floating or substrate bias conditions. These parameters are measured nearly simultaneously, controlled by a specific measurement and analysis program. The operation of this combined sensor is demonstrated for the deposition of copper and tungsten films with a 2 inch planar magnetro

Radioimmunoassay of Human Serum Serotonin

Peer Reviewe

Reactive co sputtering of Cu In,Ga S2 absorber layers role of Cu excess and ion assistance

Reactive and non reactive magnetron sputtering as a large area, low temperature, industrial deposition method is used already on a large scale in thin film photovoltaics, but only for electronically inactive films, i.e., back contacts molybdenum, silver , front contacts ITO, ZnO Al and metal precursor layers copper, indium . Though we could show recently, that reactive magnetron sputtering of CuInS2 absorber layers by co sputtering from a Cu and an In target yields cell efficiencies of more than 11 , this process is not yet stable enough for module production, partly due to insufficient understanding of the growth process. In this article we investigate the crystallization process of Cu In, Ga S2 layers by in situ, time resolved energy dispersive X ray diffraction EDXDR and study the influence of an additional plasma source on the film morphology and cell efficiencies. It is found that with increasing Cu excess the crystallization of Cu In,Ga S2 occurs at much lower temperatures down to about 200 C . This is comparable to the crystallization of evaporated CuInS2 with an CuSx top layer. An additional plasma directed to the substrate improves the efficiency of Cu In,Ga S2 cells considerably, if the plasma density is not too high. Too high plasma densities at the substrate lead to a re sputtering of the growing films. From elemental SIMS profiles it is found, that the Ga profiles are flat, an advantage compared to the sequential proces

Development of a compact combined plasma sensor for plasma surface engineering processes

A combined sensor for the investigation of plasma based surface engineering processes has been developed, which basically consists of a quartz crystal microbalance that is simultaneously used as a heat flux sensor and a planar Langmuir probe in one active element. The sensor can thus measure deposition flux, heat flux, and charged particle flux laterally resolved at the same time and position. The setup and working principle of the sensor are shown, and the suitability for process investigations is demonstrated exemplarily for a dc magnetron sputtering discharge for Ti thin film depositio