Avatars and Lebensform: Kirchberg 2007

Several years ago, after a decade of experiments in the software industry, I returned to academia and found philosophy colleagues troubled by the term “virtual reality” — a term which enjoys wide usage in the ?eld of immersive computing but which raises hackles in post-metaphysical philosophers. Some vocabulary in this paper may create similar unease, so a warning may be in order. What makes sense to software engineers may for philosophers carry too much baggage. Words like “empathetic” or “empathic” may cause similar discomfort for those with an allergy to Romanticism. While these adjectives associated with poets like Wordsworth, the term “empathy” belongs equally to software designers and video-game artists who use it to describe the opposite of “?rst-person shooter” software. Empathic, as opposed to “shoot ‘em up” software, encourages the exchange of viewpoints beyond ?rst-person perspective and may even merge several perspectives. Rather than deepen a user’s ?rst-person point-of-view, empathic software offers a socializing experience, and in fact, is sometimes called “social” software, “Net 2.0,” or “computer supported cooperative work.

Lignin content and chemical characteristics in maize and wheat vary between plant organs and growth stages: consequences for assessing lignin dynamics in soil

Assessing lignin turnover in soil on the basis of a 13C natural abundance labeling approach relies on the assumption that chemical characteristics of labeled and control plant inputs are similar and that the 13C content difference between labeled and control plant inputs is constant within the plant parts. We analyzed lignin in soils, roots, stems and leaves of wheat and maize at different stages of growth using the cupric oxide oxidation method. In both plants, lignin concentrations increased with growth, particularly during grain filling. Maize contained more cinnamyl moieties than wheat. Roots had higher lignin contents (especially cinnamyl moieties) than stems and leaves, and seemed to contribute more to the total soil lignin than the aboveground parts. The isotopic differences (∆ δ13C) of lignin phenols were not significantly different (p > 0.05) between plant organs, confirming assumptions underlying the natural abundance 13C labeling approach. Our data show that lignin content and phenol distribution can vary between plant organs and with the time of harvest. Consequently, the amount of annual lignin input may vary as a function of root amount and harvest date, and thus can affect the calculated apparent turnover times of lignin in natural abundance 13C labeling experiment

Effect of corticosteroids during ongoing drug exposure in pantoprazole-induced interstitial nephritis

Acute interstitial nephritis (AIN) represents a significant cause of acute renal failure in hospital practice. An increasing number of drugs are known to cause AIN. Due to the lack of prospective, randomized clinical trials, the most effective management is still uncertain, especially the role of steroids in the resolution of interstitial nephritis remains to be further defined. We report on a case with pantoprazole-induced interstitial nephritis and on the effect of steroids during ongoing drug exposure. In spite of ongoing drug exposure, steroids led to almost complete resolution of the inflammatory infiltrates. Early diagnosis of interstitial nephritis by renal biopsy and identification of the causative drug and its withdrawal remains the mainstay of treatment. However, the additional use of steroids has the potential to eradicate inflammatory infiltrates more rapidly and completely and may thus be important to minimize subsequent chronic damag

Bayesian Analysis of Femtosecond Pump-Probe Photoelectron-Photoion Coincidence Spectra with Fluctuating Laser Intensities

This paper employs Bayesian probability theory for analyzing data generated in femtosecond pump-probe photoelectron-photoion coincidence (PEPICO) experiments. These experiments allow investigating ultrafast dynamical processes in photoexcited molecules. Bayesian probability theory is consistently applied to data analysis problems occurring in these types of experiments such as background subtraction and false coincidences. We previously demonstrated that the Bayesian formalism has many advantages, amongst which are compensation of false coincidences, no overestimation of pump-only contributions, significantly increased signal-to-noise ratio, and applicability to any experimental situation and noise statistics. Most importantly, by accounting for false coincidences, our approach allows running experiments at higher ionization rates, resulting in an appreciable reduction of data acquisition times. In addition to our previous paper, we include fluctuating laser intensities, of which the straightforward implementation highlights yet another advantage of the Bayesian formalism. Our method is thoroughly scrutinized by challenging mock data, where we find a minor impact of laser fluctuations on false coincidences, yet a noteworthy influence on background subtraction. We apply our algorithm to data obtained in experiments and discuss the impact of laser fluctuations on the data analysis

Transfer Functions and Penetrations of Five Differential Mobility Analyzers for Sub-2 nm Particle Classification

The transfer functions and penetrations of five differential mobility analyzers (DMAs) for sub-2 nm particle classification were evaluated in this study. These DMAs include the TSI nanoDMA, the Caltech radial DMA (RDMA) and nanoRDMA, the Grimm nanoDMA, and the Karlsruhe-Vienna DMA. Measurements were done using tetra-alkyl ammonium ion standards with mobility diameters of 1.16, 1.47, and 1.70 nm. These monomobile ions were generated by electrospray followed by high resolution mobility classification. Measurements were focused at an aerosol-to-sheath flow ratio of 0.1. A data inversion routine was developed to obtain the true transfer function for each test DMA, and these measured transfer functions were compared with theory. DMA penetration efficiencies were also measured. An approximate model for diffusional deposition, based on the modified Gormley and Kennedy equation using an effective length, is given for each test DMA. These results quantitatively characterize the performance of the test DMAs in classifying sub-2 nm particles and can be readily used for DMA data inversion

Prehypertensive blood pressures and regional cerebral blood flow independently relate to cognitive performance in midlife

Background High blood pressure is thought to contribute to dementia in late life, but our understanding of the relationship between individual differences in blood pressure ( BP ) and cognitive functioning is incomplete. In this study, cognitive performance in nonhypertensive midlife adults was examined as a function of resting BP and regional cerebral blood flow ( rCBF ) responses during cognitive testing. We hypothesized that BP would be negatively related to cognitive performance and that cognitive performance would also be related to rCBF responses within areas related to BP control. We explored whether deficits related to systolic BP might be explained by rCBF responses to mental challenge. Methods and Results Healthy midlife participants (n=227) received neuropsychological testing and performed cognitive tasks in a magnetic resonance imaging scanner. A pseudocontinuous arterial spin labeling sequence assessed rCBF in brain areas related to BP in prior studies. Systolic BP was negatively related to 4 of 5 neuropsychological factors (standardized β&gt;0.13): memory, working memory, executive function, and mental efficiency. The rCBF in 2 brain regions of interest was similarly related to memory, executive function, and working memory (standardized β&gt;0.17); however, rCBF responses did not explain the relationship between resting systolic BP and cognitive performance. Conclusions Relationships at midlife between prehypertensive levels of systolic BP and both cognitive and brain function were modest but suggested the possible value of midlife intervention. </jats:sec

Near infra-red photoimmunotherapy with anti-CEA-IR700 results in extensive tumor lysis and a significant decrease in tumor burden in orthotopic mouse models of pancreatic cancer.

Photoimmunotherapy (PIT) of cancer utilizes tumor-specific monoclonal antibodies conjugated to a photosensitizer phthalocyanine dye IR700 which becomes cytotoxic upon irradiation with near infrared light. In this study, we aimed to evaluate the efficacy of PIT on human pancreatic cancer cells in vitro and in vivo in an orthotopic nude mouse model. The binding capacity of anti-CEA antibody to BxPC-3 human pancreatic cancer cells was determined by FACS analysis. An in vitro cytotoxicity assay was used to determine cell death following treatment with PIT. For in vivo determination of PIT efficacy, nude mice were orthotopically implanted with BxPC-3 pancreatic tumors expressing green fluorescent protein (GFP). After tumor engraftment, the mice were divided into two groups: (1) treatment with anti-CEA-IR700 + 690 nm laser and (2) treatment with 690 nm laser only. Anti-CEA-IR700 (100 μg) was administered to group (1) via tail vein injection 24 hours prior to therapy. Tumors were then surgically exposed and treated with phototherapy at an intensity of 150 mW/cm2 for 30 minutes. Whole body imaging was done subsequently for 5 weeks using an OV-100 small animal imaging system. Anti-CEA-IR700 antibody bound to the BxPC3 cells to a high degree as shown by FACS analysis. Anti-CEA-IR700 caused extensive cancer cell killing after light activation compared to control cells in cytotoxicity assays. In the orthotopic models of pancreatic cancer, the anti-CEA-IR700 group had significantly smaller tumors than the control after 5 weeks (p&lt;0.001). There was no significant difference in the body weights of mice in the anti-CEA-IR700 and control groups indicating that PIT was well tolerated by the mice

Overview of Dynamic Test Techniques for Flight Dynamics Research at NASA LaRC (Invited)

An overview of dynamic test techniques used at NASA Langley Research Center on scale models to obtain a comprehensive flight dynamics characterization of aerospace vehicles is presented. Dynamic test techniques have been used at Langley Research Center since the 1920s. This paper will provide a partial overview of the current techniques available at Langley Research Center. The paper will discuss the dynamic scaling necessary to address the often hard-to-achieve similitude requirements for these techniques. Dynamic test techniques are categorized as captive, wind tunnel single degree-of-freedom and free-flying, and outside free-flying. The test facilities, technique specifications, data reduction, issues and future work are presented for each technique. The battery of tests conducted using the Blended Wing Body aircraft serves to illustrate how the techniques, when used together, are capable of characterizing the flight dynamics of a vehicle over a large range of critical flight conditions

Dissolved organic matter properties in arctic coastal waters are strongly influenced by fluxes from permafrost coasts and by local meteorology.

Under future climate change scenarios, Arctic coastal waters are believed to receive higher terrestrial organic matter (OM) fluxes. Permafrost carbon is increasingly mobilized upon thaw from rivers draining permafrost terrain and from eroding permafrost coasts. Once received, the coastal waters are the transformation zone for terrestrial OM, although quantities, especially those of dissolved organic matter (DOM) released by coastal erosion, are largely unknown. This nearshore zone plays a crucial role in Arctic biogeochemical cycling, as here the released material is destined to be (1) mineralized into greenhouse gases, (2) incorporated into marine primary production, (3) buried in nearshore sediments or (4) transported offshore. In this presentation, we show data on DOM quantities in surface water in the nearshore zone of the southern Beaufort Sea from two consecutive summer seasons under different meteorological conditions. Colored dissolved organic matter (cDOM) properties help to differentiate the terrestrial from the marine DOM component. Figure 1 shows DOC concentrations and salinities for 23 and 24 days in the summer seasons of 2013 and 2014, respectively. DOC concentrations in the nearshore zone of the southern Beaufort Sea vary between about 1.5 and 5 mg C L-1. In the Lena River Delta, bay water, river water, and permafrost meltwater creeks yielded similar values between 5.8 and 5.9 mg C L-1 (Dubinenkov et al., 2015). Similarly, Fritz et al. (2015) found DOC concentrations in ice wedges between 1.6 and 28.6 mg C L-1. In 2013, the first half of July was characterized by low salinity between 8 and 15 psu and high DOC concentrations of 3.5 to 5 mg C L-1. Then, a sudden change in water properties occurred after a major storm which lasted for at least 2 days. This storm led to strongly decreased DOC (1.5 to 2.5 mg C L-1) concentration and increasing salinity (14 to 28 psu) in surface water, probably due to upwelling In 2014, a more stable situation in both salinity and DOC prevailed, with relatively high salinity (23 to 29 psu) and low DOC concentration (1.5 to 2.5 mg C L-1). This pattern was due to rather windy and wavy conditions throughout the whole season. The water column in 2014 was likely well-mixed and DOC-poor because saline waters have probably been transported from the offshore to the nearshore. We recognized a significant negative correlation between DOC and salinity, independent from varying meteorological conditions. In general, this suggests a conservative mixing between DOC derived from terrestrial/permafrost runoff and marine DOC. The low salinity in July 2013 was probably due to prolonged sea-ice presence in the sampled area. This leads to the assumption that DOC also originates from melting sea ice. Quantitatively more important will be terrestrial runoff which is relatively rich in DOC. A stable stratification in the nearshore zone and calm weather conditions will increase the influence of terrestrial-derived DOM. The strength of the terrestrial influence can be estimated by salinity measures as they directly correlate with DOC concentrations; the lower the salinity the stronger the terrestrial influence. We conclude that the terrestrial imprint of coastal erosion on DOM concentrations in the nearshore zone is significant. We see that DOC concentrations are significantly elevated also compared to riverine input in front of river mouths and deltas. Meteorological conditions play a major role for the strength of the terrestrial DOM signal, which can vary on short timescales. Our approach is different from ship-based oceanography because we study DOM that is directly derived from thawing permafrost coasts, explicitly excluding rivers. When qualifying DOM origin from permafrost landscapes apart from rivers we have to take into consideration the different DOM mobilization pathways. 1) Surface runoff and near-surface groundwater flow mainly drain and flush the active layer. 2) Melting ground ice releases DOM. 3) Ground ice meltwater leaches DOM from sedimentary OM upon permafrost thaw on land. 4) DOM is leached from sedimentary OM upon contact with sea water. The latter three will mobilize old OM which is believed to be highly bioavailable (see Vonk et al., 2013a, b). References: Dubinenkov, I., Flerus, R., Schmitt-Kopplin, P., Kattner, G., Koch, B.P., 2015. Origin-specific molecular signatures of dissolved organic matter in the Lena Delta. Biogeochemistry 123, 1-14. Fritz, M., Opel, T., Tanski, G., Herzschuh, U., Meyer, H., Eulenburg, A., Lantuit, H., 2015. Dissolved organic carbon (DOC) in Arctic ground ice. The Cryosphere 9, 737-752. Vonk, J.E., Mann, P.J., Davydov, S., Davydova, A., Spencer, R.G.M., Schade, J., Sobczak, W.V., Zimov, N., Zimov, S., Bulygina, E., Eglinton, T.I., Holmes, R.M., 2013a. High biolability of ancient permafrost carbon upon thaw. Geophysical Research Letters 40, 2689-2693. Vonk, J.E., Mann, P.J., Dowdy, K.L., Davydova, A., Davydov, S.P., Zimov, N., Spencer, R.G.M., Bulygina, E.B., Eglinton, T.I., Holmes, R.M., 2013b. Dissolved organic carbon loss from Yedoma permafrost amplified by ice wedge thaw. Environmental Research Letters 8, 035023

Horizontal gene transfer contributed to the evolution of extracellular surface structures

The single-cell layered ectoderm of the fresh water polyp Hydra fulfills the function of an epidermis by protecting the animals from the surrounding medium. Its outer surface is covered by a fibrous structure termed the cuticle layer, with similarity to the extracellular surface coats of mammalian epithelia. In this paper we have identified molecular components of the cuticle. We show that its outermost layer contains glycoproteins and glycosaminoglycans and we have identified chondroitin and chondroitin-6-sulfate chains. In a search for proteins that could be involved in organising this structure we found PPOD proteins and several members of a protein family containing only SWT (sweet tooth) domains. Structural analyses indicate that PPODs consist of two tandem β-trefoil domains with similarity to carbohydrate-binding sites found in lectins. Experimental evidence confirmed that PPODs can bind sulfated glycans and are secreted into the cuticle layer from granules localized under the apical surface of the ectodermal epithelial cells. PPODs are taxon-specific proteins which appear to have entered the Hydra genome by horizontal gene transfer from bacteria. Their acquisition at the time Hydra evolved from a marine ancestor may have been critical for the transition to the freshwater environment