129 research outputs found

    Plasma-Surface Interactions of Model Polymers for Advanced Photoresist Systems

    Get PDF
    Plasma processing of advanced photoresist (PR) materials is a critical step in nano-manufacturing. We have studied the interactions of PRs and polymers in fluorocarbon/Ar discharges. The effects of process time, PR material, bias and source power, pressure and gas chemistry (C4F8/Ar, CF4/Ar and CF4/H2/Ar) were studied by ellipsometry, atomic force microscopy and x-ray photoelectron spectroscopy. Additionally, patterned structures of 193nm PR were examined using scanning electron microscopy. Polymer destruction in the top surface, oxygen and hydrogen loss along with fluorination were observed for all materials initially, which was followed by steady state etch conditions. A strong dependence of plasma-induced surface chemical and morphological changes on polymer structure was observed. In particular, the adamantane group of 193 nm PR showed poor stability. Two linked mechanisms for the roughening behavior of the films during processing were identified: A physical pattern transfer mechanism enhances initial roughness by non-uniform removal. Additional to that, roughness formation occurred linear to the energy density deposited during processing. For adamantyl polymers, a higher roughening constant was found. Additionally, fluorocarbon (FC) deposition on the damaged PR affected roughening in two opposing ways: Ion-induced mixing with the damaged PR increased roughening, whereas for simple FC precursor deposition a reduction of roughness was seen. Fluorination of the PR surfaces using plasma increased etching yields, which were found to improve the roughness of 193nm PR after etch. The fluorination of the PR prevented the formation of characteristic small scale roughness features at the cost of large scale roughness introduction. Use of low energy density processes suppressed the roughness growth by ion-induced transfer. Examining 3-dimensional trenches and contact holes patterned in PR showed that the sidewall roughness changed with process parameters similar to that seen for blanket films. The close correlation suggested that our model of polymer surface roughening also applies to resist sidewall evolution during etch. All process conditions can be combined in the energy density roughening model. Even for various feedgas chemistries adamantyl containing polymers show enhanced roughening rates, suggesting that the instability of the adamantyl structure used in 193nm PR polymers is the performance limiting factor for processing PR materials

    Exhaled breath condensate acidification in acute lung injury

    Get PDF
    AbstractLung injury in ventilated lungs may occur due to local or systemic disease and is usually caused by or accompanied by inflammatory processes. Recently, acidification of exhaled breath condensate pH (EBC-pH) has been suggested as marker of inflammation in airway disease. We investigated pH, ammonia, lactate, pCO2, HCO3−, IL-6 and IL-8 in EBC of 35 ventilated patients (AECC-classification: ARDS: 15, ALI: 12, no lung injury: 8).EBC-pH was decreased in ventilated patients compared to volunteers (5.85±0.32 vs. 7.46±0.48; P<0.0001). NH4+, lactate, HCO3−, pCO2, IL-6 and IL-8 were analyzed in EBC and correlated with EBC-pH. We observed correlations of EBC-pH with markers of local (EBC IL-6: r=−0.71, P<0.0001, EBC IL-8: r=−0.68, P<0.0001) but not of systemic inflammation (serum IL-6, serum IL-8) and with indices of severity of lung injury (Murray's Lung Injury Severity Score; r=−0.73, P<0.0001, paO2/FiO2; r=0.54, P<0.001). Among factors potentially contributing to pH of EBC, EBC-lactate and EBC-NH4+ were found to correlate with EBC-pH.Inflammation-induced disturbances of regulatory mechanisms, such as glutaminase systems may result in EBC acidification. EBC-pH is suggested to represent a marker of acute lung injury caused by or accompanied by pulmonary inflammation

    Ascites’ neutrophil function is significantly impaired in patients with decompensated cirrhosis but can be restored by autologous plasma incubation

    Get PDF
    Systemic immune cell dysfunction is a typical feature of liver diseases and increases the risk of bacterial infection, especially spontaneous bacterial peritonitis. We evaluated functional properties of neutrophil granulocytes in blood and ascites of patients both with and without decompensated cirrhosis. We collected blood and ascites samples from 63 patients with cirrhosis and eight without cirrhosis. Phagocytosis activity (PA) and oxidative burst activity (OBA) were evaluated after ex vivo stimulation with E. coli, while fluorescence signals were measured by flow cytometry. Ascites’ neutrophil function tests were repeated after incubation with autologous plasma. Ascites’ neutrophils showed an impaired PA and OBA (median blood PA 98.1% (86.8–99.8) vs. ascites’ PA 50.5% (0.4–97.3), p < 0.0001; median blood OBA 98.7% (27.5–100) vs. ascites’ OBA 27.5% (0.3–96.7), p < 0.0001). Patients with non- cirrhotic ascites showed higher PA but equally suppressed OBA. Ascites’ neutrophil function could be partially restored after incubation with autologous plasma (median increase PA: 22.5% (−49.7 – +93.2), p = 0.002; OBA: 22.8% (−10.4 – +48.8), p = 0.002). Ascites’ neutrophils of patients with cirrhosis are functionally impaired, but could be partially restored after incubation with plasma. Further investigations are needed to identify the factors in ascites that are associated with neutrophils’ function

    Life within a limited radius: Investigating activity space in women with a history of child abuse using global positioning system tracking

    Get PDF
    Early experiences of childhood sexual or physical abuse are often associated with functional impairments, reduced well-being and interpersonal problems in adulthood. Prior studies have addressed whether the traumatic experience itself or adult psychopathology is linked to these limitations. To approach this question, individuals with posttraumatic stress disorder (PTSD) and healthy individuals with and without a history of child abuse were investigated. We used global positioning system (GPS) tracking to study temporal and spatial limitations in the participants’ real-life activity space over the course of one week. The sample consisted of 228 female participants: 150 women with PTSD and emotional instability with a history of child abuse, 35 mentally healthy women with a history of child abuse (healthy trauma controls, HTC) and 43 mentally healthy women without any traumatic experiences in their past (healthy controls, HC). Both traumatized groups—i.e. the PTSD and the HTC group—had smaller movement radii than the HC group on the weekends, but neither spent significantly less time away from home than HC. Some differences between PTSD and HC in movement radius seem to be related to correlates of PTSD psychopathology, like depression and physical health. Yet group differences between HTC and HC in movement radius remained even when contextual and individual health variables were included in the model, indicating specific effects of traumatic experiences on activity space. Experiences of child abuse could limit activity space later in life, regardless of whether PTSD develops.Peer Reviewe

    On the knee in the energy spectrum of cosmic rays

    Get PDF
    The knee in the all-particle energy spectrum is scrutinized with a phenomenological model, named poly-gonato model, linking results from direct and indirect measurements. For this purpose, recent results from direct and indirect measurements of cosmic rays in the energy range from 10 GeV up to 1 EeV are examined. The energy spectra of individual elements, as obtained by direct observations, are extrapolated to high energies using power laws and compared to all-particle spectra from air shower measurements. A cut-off for each element proportional to its charge Z is assumed. The model describes the knee in the all-particle energy spectrum as a result of subsequent cut-offs for individual elements, starting with the proton component at 4.5 PeV, and the second change of the spectral index around 0.4 EeV as due to the end of stable elements (Z=92). The mass composition, extrapolated from direct measurements to high energies, using the poly-gonato model, is compatible with results from air shower experiments measuring the electromagnetic, muonic, and hadronic components. But it disagrees with the mass composition derived from X_max measurements using Cerenkov and fluorescence light detectors.Comment: 30 pages, 21 figures, 9 tables, accepted by Astroparticle Physic

    Successful direct acting antiviral (DAA) treatment of HCV/HIV-coinfected patients before and after liver transplantation

    Get PDF
    Objectives The aim of this multicenter retrospective study was to investigate safety and efficacy of direct acting antiviral (DAA) treatment in the rare subgroup of patients with HCV/HIV-coinfection and advanced liver cirrhosis on the liver transplant waiting list or after liver transplantation, respectively. Methods When contacting 54 German liver centers (including all 23 German liver transplant centers), 12 HCV/HIV-coinfected patients on antiretroviral combination therapy were reported having received additional DAA therapy while being on the waiting list for liver transplantation (patient characteristics: Child-Pugh A (n = 6), B (n = 5), C (n = 1);MELD range 7-21;HCC (n = 2);HCV genotype la (n = 8), 1 b (n = 2), 4 (n = 2)). Furthermore, 2 HCV/HIV-coinfected patients were denoted having received DAA therapy after liver transplantation (characteristics: HCV genotype 1a (n = 1), 4 (n = 1)). Results Applied DAA regimens were SOF/DAC (n = 7), SOF/LDV/RBV (n = 3), SOF/RBV (n = 3), PTV/r/OBV/DSV (n = 1), or PTV/r/OBV/DSV/RBV (n = 1), respectively. All patients achieved SVR 12, in the end. In one patient, HCV relapse occurred after 24 weeks of SOF/DAC therapy;subsequent treatment with 12 weeks PTV/r/OBV/DSV achieved SVR 12. One patient underwent liver transplantation while on DAA treatment. Analysis of liver function revealed either stable parameters or even significant improvement during DAA therapy and in followup. MELD scores were found to improve in 9/13 therapies in patients on the waiting list for liver transplantation;in only 2 patients a moderate increase of MELD scores persisted at the end of follow-up. Conclusion DAA treatment was safe and highly effective in this nation-wide cohort of patients with HCV/HIV-coinfection awaiting liver transplantation or being transplanted

    Positive taxis and sustained responsiveness to water motions in larval zebrafish

    Get PDF
    Larval zebrafish (Danio rerio) have become favored subjects for studying the neural bases of behavior. Here, we report a highly stereotyped response of zebrafish larvae to hydrodynamic stimuli. It involves positive taxis, motion damping and sustained responsiveness to flows derived from local, non-stressful water motions. The response depends on the lateral line and has a high sensitivity to stimulus frequency and strength, sensory background and rearing conditions—also encompassing increased threshold levels of response to parallel input. The results show that zebrafish larvae can use near-field detection to locate sources of minute water motions, and offer a unique handle for analyses of hydrodynamic sensing, sensory responsiveness and arousal with accurate control of stimulus properties
    • …
    corecore