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Most metal forming processes use lubricants based on mineral oils as an intermediate medium to reduce friction and wear. To avoid the well-known drawbacks of oil lubrication, a novel and environment friendly lubrication system for deep-drawing processes was demonstrated at the University of Stuttgart. Liquid carbon dioxide and gaseous nitrogen are being used as volatile lubrication during the deep-drawing process, locally injected at high pressure through laser-drilled microholes. This new tribological system provides a significantly enlarged working range and at least 15% larger drawing depths compared to conventional oil lubrication.

Most metal forming processes use lubricants based on mineral oils as an intermediate medium to reduce friction and wear. To avoid the well-known drawbacks of oil lubrication, a novel and environment friendly lubrication system for deep-drawing processes was demonstrated at the University of Stuttgart. Liquid carbon dioxide and gaseous nitrogen are being used as volatile lubrication during the deep-drawing process, locally injected at high pressure through laser-drilled microholes. This new tribological system provides a significantly enlarged working range and at least 15% larger drawing depths compared to conventional oil lubrication.

Nowadays, it is more important than ever to meet the increasing technical and statutory requirements and to develop new process strategies. In sheet metal forming the low consumption of oil lubrication gets an increasingly important role. The aim in sheet metal forming is to reduce the amounts of lubricants. In the long term, the future sheet metal processing should be able to completely dispense without mineral oil-containing lubricants. Two promising approaches for a dry process design are combined in this paper for the first time and the fundamental feasibility of this new hybrid technology is shown. On the one hand, a novel approach for temporary lubrication of deep-drawing processes with CO2 as a volatile medium is used. On the other hand, it is supported by the application of an additional hard coating system such as a silicon nitride (Si3N4) or tungsten doped a-C:H multilayered (Cr/CrNx/a-C:H:W/a-C:H) coating system to further reduce tool wear and wear debris of the formed sheets made of DC04 (mat. no.: 1.0338). The results show a low coefficient of friction and reduced wear. Especially for the carbon coating system, there is minor tool wear at a higher surface pressure. By means of the graphite constituent, even a smoothening of the roughness peaks can be recorded. The next step would be the implementation of this hybrid technology on a tool for deep drawing a rectangular cup.

(1) Background: Cervical intraepithelial neoplasia (CIN) of long-term persistence or associated with individual treatment indications often requires highly invasive treatments. These are associated with risks of bleeding, infertility, and pregnancy complications. For low- and middle-income countries (LMICs), standard treatment procedures are difficult to implement and manage. We characterized the application of the highly energized gas "noninvasive physical plasma" (NIPP) for tissue devitalization and the treatment of CIN. (2) Methods: We report the establishment of a promising tissue devitalization procedure by NIPP application. The procedure was characterized at the in vitro, ex vivo and in vivo levels. We performed the first prospective, single-armed phase-IIb trial in 20 CIN1/2 patients (NCT03218436). (3) Results: NIPP-treated cervical cancer cells used as dysplastic in vitro model exhibited significant cell growth retardation due to DNA damage, cell cycle arrest and apoptosis. Ex vivo and in vivo tissue assessments showed a highly noninvasive and tissue-preserving treatment procedure which induces transmucosal tissue devitalization. Twenty participants were treated with NIPP and attended a 24-week follow-up. Treatment success was achieved in 19 (95%) participants without postinterventional complications other than mild to moderate discomfort during application. (4) Conclusions: The results from this study preliminarily suggest that NIPP could be used for an effective and tissue-preserving treatment for CIN without the disadvantages of standard treatments. However, randomized controlled trials must confirm the efficacy and noninferiority of NIPP compared to standard treatments.

To gain comprehensive insight into the interactions of key coffee odorants, like the Strecker aldehydes, acetaldehyde, propanal, methylpropanal, 2- and 3-methylbutanal, and methional, and the nonvolatile fraction of coffee, an untargeted metabolomics approach was applied. Ultra performance liquid chromatography (UPLC)-time of flight (TOF)-mass spectrometry (ESI - ) profiling followed by statistical data analysis revealed a marker substance for a coffee beverage spiked with acetaldehyde with an accurate mass of 217.0703 [M - H] - . This compound could be identified as a reaction product of quinic acid (QA) and acetaldehyde linked by acetalization at the cis -diol function of QA. Consequently, the acetalization of aldehydes, QA, 5- O -caffeoyl quinic acid (CQA), and quinic acid γ-lactone (QAL) was investigated by means of model reactions, followed by synthesis, isolation, and structure elucidation via UPLC-TOF-MS and 1D and 2D NMR techniques. UHPLC-MS/MS MRM screening and the quantification of aldehyde adducts in coffee beverages revealed the presence of QA/acetaldehyde, -/propanal, -/methylpropanal, and -/methional reaction products and CQA/acetaldehyde, -/propanal, -/methylpropanal, -/2- and 3-methylbutanal, and -/methional and QAL/acetaldehyde adducts for the first time, in concentrations of 12-270 μg/L for QA/aldehydes, 5-225 μg/L for CQA/aldehydes, and 62-173 μg/L for QAL/acetaldehyde. The sensory characterization of the identified compounds showed bitter taste recognition thresholds of 48-297 μmol/L for CQA adducts and 658 μmol/L for QAL/acetaldehyde, while the QA adducts showed no bitter taste (<2000 μmol/L).

Human adipose-derived stem cells (hASCs) have become an important cell source for the use in tissue engineering and other medical applications. Not every biomaterial is suitable for human cell culture and requires surface modifications to enable cell adhesion and proliferation. Our hypothesis is that chemical surface modifications introduced by low-discharge plasma enhance the adhesion and proliferation of hASCs. Polystyrene (PS) surfaces were modified either by ammonia (NH 3 ), carbon dioxide (CO 2 ) or acrylic acid (AAc) plasma. The results show that the initial cell adhesion is significantly higher on all modified surfaces than on unmodified material as evaluated by bright field microscopy, live/dead staining, total DNA amount and scanning electron microscopy. The formation of focal adhesions was well pronounced on the Tissue Culture PS, NH 3 -, and CO 2 -plasma modified samples. The number of matured fibrillar adhesions was significantly higher on NH 3 -plasma modified surfaces than on all other surfaces. Our study validates the suitability of chemical plasma activation and represents a method to enhance hASCs adhesion and improved cell expansion. All chemical modification promoted hASCs adhesion and can therefore be used for the modification of different scaffold materials whereby NH 3 -plasma modified surfaces resulted in the best outcome concerning hASCs adhesion and proliferation., (© 2019 Wiley Periodicals, Inc.)

Cold atmospheric plasma (CAP) treatment is developing as a promising option for local anti-neoplastic treatment of dysplastic lesions and early intraepithelial cancer. Currently, high-frequency electrosurgical argon plasma sources are available and well established for clinical use. In this study, we investigated the effects of treatment with a non-thermally operated electrosurgical argon plasma source, a Martin Argon Plasma Beamer System (MABS), on cell proliferation and metabolism of a tissue panel of human cervical cancer cell lines as well as on non-cancerous primary cells of the cervix uteri. Similar to conventional CAP sources, we were able to show that MABS was capable of causing antiproliferative and cytotoxic effects on cervical squamous cell and adenocarcinoma as well as on non-neoplastic cervical tissue cells due to the generation of reactive species. Notably, neoplastic cells were more sensitive to the MABS treatment, suggesting a promising new and non-invasive application for in vivo treatment of precancerous and cancerous cervical lesions with non-thermally operated electrosurgical argon plasma sources.

Nonthermal treatment with cold atmospheric plasma (CAP) is a promising option for local treatment of chronic-inflammatory and precancerous lesions as well as various mucosal cancer diseases, besides its primary indication for wound healing and antiseptics. Atmospheric pressure plasma jets (APPJs) are versatile plasma sources, some of which are well-characterized and medically approved. The characterization of APPJs, however, is often based on the treatment of simple solutions or even studies on the plasma effluent itself. To better assess the in vivo effects of CAP treatment, this study aims to recapitulate and study the physicochemical tissue-level effects of APPJ treatment on human primary mucosal tissue and tissue models. High resolution on-tissue infrared (IR) thermography and a first-time-performed spatially resolved optical emission spectroscopy (OES) of the APPJ emissions did not identify potentially tissue-harming effects. In this study, electron-spin-resonance (ESR) spectroscopy on human tissue samples, treated with different CAP doses, enabled the measurement and the distribution of CAP-derived radicals in the tissues. The results correlate plasma dosage and the generation of radical species with cell viability and cell proliferation of primary human fibroblasts while demonstrating apoptosis-independent antiproliferative cell effects. Moreover, a dose-dependent increase of cells in the G1 phase of the cell cycle was observed, stressing the likely important role of cell cycle regulation for antiproliferative CAP mechanisms. This study introduces suitable methods for CAP monitoring on tissues and contributes to a better understanding of tissue-derived plasma effects of APPJs.

The control of surface properties is a substantial step in the development and improvement of biomaterials for clinical applications as well as for their use in tissue engineering. Interaction of the substrate surface with the biochemical or biological environment is crucial for the outcome of the applied biomaterial and therefore should meet specific requirements regarding the chemical composition, wettability, elasticity, and charge. In this study, we examined the effect of chemical groups introduced by low pressure plasma treatments of polystyrene surfaces on the cell behavior of primary human mesenchymal stem cells (hMSCs) and dermal microvascular endothelial cells (hDMECs). X-ray photoelectron spectroscopy analysis and contact angle measurements were employed to evaluate ammonia-, carbon dioxide-, and acrylic acid-plasma modifications to substrate surfaces. HMSCs and hDMECs were analyzed simultaneously to identify the most suitable surface functionalization for each cell type. Significantly higher cell proliferation was detected on ammonia plasma-treated surfaces. Cell-material interaction could be shown on all created interfaces as well as the expression of typical cell markers. Hence, the applied plasma treatment presents a suitable tool to improve culture condition on polystyrene for two important cell types (hMSCs and hDMECs) in the field of tissue engineering., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A multicentre study involving 36 out of 38 German medico-legal Institutes discovered 784 non-natural fatalities among 78,000 external examinations before cremation (1%) in 1995. These included 169 accidents, 16 suicides, 3 homicides and 589 deaths in connection with medical treatment. In the remaining 7 cases, a belated differentiation between homicide and accident was not successful. A linear projection results in 1980 non-natural fatalities among all 197,000 external examinations before cremation. This number includes 8 homicides but due to considerable inhomogeneities, a number of 40 homicides appears to be realistic. Consequently, abolishing the mandatory external examination before cremation would be equivalent to an official renouncement of solving relevant non-natural deaths. In case of a thorough external examination, a total of 18,000 non-natural fatalities including approximately 180 homicides could be detected per year during the first external examinations (n = 885,000).

The paper reports on a remarkable case of corpse disposal. A 32-year-old inmate of a prison with the permission to go out on weekends had disappeared since 1 1/4 years. His corpse poured in a concrete block was found in a metal-drum having been sunk in a disused part of a river. Although formation of adipocere and putrefaction was found, the corpse was in a relatively good status of conservation. The man had been killed by a punch of a forked crowbar on his head.

Although traffic participation of bicycle riders is steadily increasing only few investigations concerning "riding while intoxicated" are available. This study examines the blood sample records of all blood samples submitted to the Duesseldorfer Institute of Forensic Medicine for blood alcohol analysis from 1986 to 1990 with respect to the participation of bicycle riders. As to the most important epidemiologic data: The proportion of samples from bicyclists increased from 2.6% in 1986 to 4.8% in 1990. Women account for 6.5%. 36.8% are younger than 30 years. Most bicycle riders were apprehended during the months of summer, on the days of the weekend and in the hours around midnight. 67.3% displayed a BAC above the legal limit for bicycle riders of 1.7 g/l. In comparison only 34.5% were judged highly drunken on medical examination. Regarding the group with a BAC above 2.5 g/l expected to be highly intoxicated 37.7% only appeared slightly or moderately impaired rising the suspicion of high alcohol tolerance.