"CITY 2020+": assessing climate change impacts for the city of Aachen related to demographic change and health – a progress report

Abstract. The research initiative CITY 2020+ assesses the risks and opportunities for residents in urban built environments under projected demographic and climate change for the year 2020 and beyond, using the city of Aachen as a case study. CITY 2020+ develops strategies, options and tools for planning and developing sustainable future city structures. The investigation focuses on how urban environment, political structure and residential behaviour can best be adapted, with attention to the interactions among structural, political, and sociological configurations and their impacts on human health. The interdisciplinary research is organized in three clusters. Within the first cluster, strategies of older people exposed to heat stress, and their networks as well as environmental health risks according to atmospheric conditions are examined. The second cluster addresses governance questions, urban planning and building technologies as well as spatial patterns of the urban heat island. The third cluster includes studies on air quality related to particulate matter and a historical perspective of city development concerning environmental issues and climate variability. However, it turns out that research topics that require an interdisciplinary approach are best addressed not by pre-structuring the work into related sub-projects but through combining them according to shared methodological approaches. Examples illustrating this rather practical approach within ongoing research are presented in this paper.

Interventional lung assist enables lung protective mechanical ventilation in acute respiratory distress syndrome

BACKGROUND

The feasibility and safety of a pumpless arteriovenous extracorporeal lung assist system (pECLA) has been demonstrated in previous studies of patients with severe respiratory insufficiency. The aim of this report was to examine whether pECLA is feasible in a center that is new to the technology and to determine the positive and adverse effects associated with its use.

METHODS

This was a retrospective case series of 13 consecutive patients with established acute respiratory distress syndrome (ICU patients with ARDS or ALI) at a university hospital. Management consisted of transcutaneous placement of a femoral arteriovenous pECLA to allow lung-protective ventilation. Nonparametric statistics were applied; all data are values and standard deviations (SD).

RESULTS

Mean simplified acute physiology score (SAPS) II was 49.5 (26); ICU mortality was 54% (7/13). Mean length of ICU stay was 34.5 (65.3) days for survivors (S) and 36 (32.8) days for non-survivors (NS). Total time on arteriovenous pECLA was 12.0 (22.2) days (S) and 7.0(7.8) days (NS), total time on mechanical ventilation was 31.0 (28.2) (S) and 32.0 (15.2) days (NS). Hypercapnia was significantly (P<0.05) reduced from 80.0 (23.0) (pre-pECLA) to 48.0 (13.0) mmHg (day 7), as were minute ventilation and inspiratory pressure. pECLA was accompanied by a significant (P<0.05) increase in the PaO2/fraction of inspired oxygen (P/F) ratio from 100.0 (28.9) (pre-pECLA) to 191.1 (114.3) mmHg after 7 days of treatment. Major complications were two inadvertent decannulations in the first two patients treated; there was one minor bleeding event in a patient seen subsequently.

CONCLUSION

pECLA is an effective and manageable technique to support gas exchange in ARDS patients. This retrospective case series demonstrates the feasibility of pECLA in a center that did not have prior experience with this technique. pECLA may decrease further lung injury by minimizing the amount of time for which the lung is exposed to high stress and/or strain.

[Cerebral reorganization in chronic low back pain and neurostimulation to improve motor control]

Chronic recurrent pain results in brain reorganization for cortical sensory and motor representation of muscles. This review supports the hypothesis that maladaptive plasticity in chronic low back pain patients could be associated with disorders of volitional activation of trunk/pelvis muscles and alterations of their anticipatory motor patterns for postural control. This is actually observed for the transversus abdominis muscle, an abdominal muscle that stabilizes the lumbosacral spine against external and internal postural perturbations. Indeed, voluntary activation of this muscle is more difficult in low back pain and a posterolateral translation of its cortical motor representation is observed in association with a delay of its anticipatory activation (usually observed in any focal limb movement). During physiotherapy, low back pain patients are trained to hollowing for contracting the transversus abdominis muscle, which normalizes both activation delays and cortical motor representation. This motor rehabilitation could be potentiated by peripheral repetitive magnetic stimulation directly over the nerves/muscles. This review introduces the magnetic stimulation technique and proposes to combine peripheral theta-burst stimulation to conventional therapy for increasing the functional gain. This may facilitate the activation of sensory afferents and modulate cortical plasticity to improve (or even re-activate) the sensorimotor control and possibly influence pain. Peripheral magnetic stimulation as an ancillary treatment adjuvant for promoting motor control in low back pain might also be relevant in any other neurological or musculoskeletal disorder with underlying maladaptive brain reorganization.

The [Formula: see text] massive operator matrix elements of [Formula: see text] for the structure function [Formula: see text] and transversity

The contributions [Formula: see text] to the [Formula: see text] massive operator matrix elements describing the heavy flavor Wilson coefficients in the limit [Formula: see text] are computed for the structure function [Formula: see text] and transversity for general values of the Mellin variable N. Here, for two matrix elements, [Formula: see text] and [Formula: see text], the complete result is obtained. A first independent computation of the contributions to the 3-loop anomalous dimensions [Formula: see text], [Formula: see text], and [Formula: see text] is given. In the computation advanced summation technologies for nested sums over products of hypergeometric terms with harmonic sums have been used. For intermediary results generalized harmonic sums occur, while the final results can be expressed by nested harmonic sums only.

[Interventions by clinical pharmacists on surgical wards - impact on antibiotic therapy]

BACKGROUND

Antibiotics are undeniably beneficial. However, inappropriate or incorrect use puts patients at risk for avoidable adverse drug reactions, promotes emergence of resistance and potentially increases overall health-care costs. The objective of this study was to assess the impact of pharmaceutical consulting on the quality and costs of antibiotic use in surgical wards.

PATIENTS AND METHODS

From February 2007 to February 2008 a total of 638 patients were enrolled in the controlled intervention study. Within the control period (n = 317) the current pattern of anti-biotic use was monitored without intervening, in the intervention period (n = 321) the pharmacist gave advice with regard to optimised antibiotic therapy.

RESULTS

In 216 patients 331 antibiotic-related problems were identified; 232 interventions resulted in a modification of therapy (acceptance 70 %). The most common interventions were those regarding the duration of therapy and the choice of agent. The intervention with the greatest acceptance (91 %) was dosing recommendations. The pharmaceutical intervention resulted in a shorter duration of therapy (9.9 vs. 11.2 days, p < 0.001) and an increased adherence to the surgical department's guidelines (64 % vs. 71 %, p = 0.03). Intravenous therapy was switched to oral therapy earlier and more often (p = 0.006). As a result, the total cost for intravenous antibiotics decreased from € 96 500.- to € 81 600.- (p = 0.001). Dosage recommendations (e. g. in impaired organ function) or information on interaction and side effects increased drug -safety.

CONCLUSION

Using the example of antibiotic therapy we showed that pharmaceutical counselling on surgical wards influences various aspects of antibiotic therapy, increases drug safety and reduces cost by having an effect on duration of therapy and timely switch from intravenous to oral preparations.

[Interventional, intramyocardial stem cell therapy in ischemic cardiomyopathy: update 2010]

BACKGROUND

The intracoronary application of autologous bone marrow cells has proven hitherto to be safe but not sufficiently effective in patients with ischemic cardiomyopathy. The interventional application of cells injected directly into the myocardium represents one possible approach to improve effectiveness.

TECHNIQUES

The NOGA method is based on the CARTO technique, which has been evaluated extensively for safety and feasibility in patients with heart failure. In a first step, an electrically and anatomically exact map of the left ventricle is obtained. Guided by this three-dimensional map direct injection of the cells into the ischemic area can be easily performed.

CLINICAL STUDIES

Since its introduction in 2002 many studies have proven the safety, feasibility and effectiveness of NOGA-guided regenerative therapy to the left ventricle. While several studies also suggest effectiveness regarding various parameters of left ventricular function, no larger multicenter study is available to date. Such studies with also clinical endpoints are currently ongoing.

CONCLUSION

The currently available data support, but do not yet prove, the hypothesis that intramyocardial stem cell therapy using NOGA-guided injection into the myocardium is safe and feasible in both acute and chronic ischemic cardiomyopathy. Ongoing trials will reveal whether this approach will become the standard form for applying cell therapy to the heart.

Polarized nonequilibrium Bose-Einstein condensates of spinor exciton polaritons in a magnetic field

The effect of a magnetic field on a spinor exciton-polariton condensate has been investigated. A quenching of a polariton Zeeman splitting and an elliptical polarization of the condensate have been observed at low magnetic fields B<2 T. The effects are attributed to a competition between the magnetic field induced circular polarization buildup and the spin-anisotropic polariton-polariton interaction which favors a linear polarization. The sign of the circular polarization of the condensate emission at B<3 T is negative, suggesting that a dynamic condensation in the excited spin state rather than the ground spin state takes place in this magnetic field range. From about 2T on, the Zeeman splitting opens and from then on the slope of the circular polarization degree changes its sign. For magnetic fields larger than the 3 T, the upper spin state occupation is energetically suppressed and circularly polarized condensation takes place in the ground state.

Effect of dietary concentrate on rumen fermentation, digestibility, and nitrogen losses in dairy cows

The objective of this experiment was to investigate the effect of level of dietary concentrate on rumen fermentation, digestibility, and N losses in lactating dairy cows. The experiment was a replicated 3x3 Latin square design with 6 cows and 16-d adaptation periods. Ruminal contents were exchanged between cows at the beginning of each adaptation period. Data for 2 of the diets tested in this experiment are presented here. The diets contained (dry matter basis): 52% (LowC; control) and 72% (HighC) concentrate feeds. Crude protein contents of the diets were 16.5 and 16.4%, respectively. The HighC diet decreased ruminal pH and ammonia concentration and increased propionate concentration compared with LowC. Acetate:propionate ratio was greater for LowC than for HighC. Rumen methane production and microbial protein synthesis were unaffected by diet. Dry matter intake was similar among diets, but milk yield was increased by HighC compared with LowC (36.0 and 33.2 kg/d, respectively). Milk fat percentage and yield and total-tract apparent NDF digestibility were decreased by HighC compared with LowC. More ruminal ammonia N was transferred into milk protein with HighC than with LowC. Urinary N excretion, plasma urea N, and milk urea N concentration were not affected by diet. The ammonia emitting potential of manure was similar between LowC and HighC diets. Increased concentrate proportion in the diet of dairy cows resulted in reduced ruminal ammonia concentration and enhanced ammonia utilization for milk protein synthesis. These effects, however, did not result in reduced urinary N losses and only marginally improved milk N efficiency. Increasing dietary concentrate was not a successful strategy to mitigate enteric methane production and ammonia emissions from manure.

[Impact of systematic lymph node dissection in the resection of pulmonary metastases of solid extrapulmonary tumours]

BACKGROUND

The systematic mediastinal and hilar lymph node dissection for the treatment of pulmonary metastases has, until now, not attracted much attention. A possible advantage of systematic lymph node dissection is an improved staging and a better locoregional tumour control due to resection of tumour micrometastases and the disintegration of lymphatic vessels. Aim of the study was to investigate the impact of mediastinal and hilar lymphnode metastases on the prognosis of the patient.

METHODS AND RESULTS

Between 1978 and 2006, 249  patients underwent resection of pulmonary metastases from renal cell (91), colorectal (89), breast (45) and head and neck cancer (24), in combination with a systematic mediastinal and hilar lymphnode dissection. Survival was analysed by the Kaplan-Meier method. Multivariate analysis was performed using Cox regression analysis. Lymph node metastases were histologically demonstrated in 25.3 % of all patients. They did not correlate with the tumour grading and lymph node status of the primary tumour or the number of pulmonary metastases. Patients with lymph node metastases had a significantly shorter median survival than patients without (18 vs. 53  months, p < 0.001). Patients who underwent a systematic mediastinal and hilar lymph node dissection showed a trend to a prolonged survival (39.1 vs. 31.9  months, p = 0.089).

CONCLUSION

Mediastinal and hilar lymph node metastases are significantly correlated with decreased survival. Systematic mediastinal and hilar lymphadenectomy provides valuable information for the staging and prognosis of patients with pulmonary metastases of kidney, head and neck, breast and colorectal cancers and may help to distinguish those patients who might profit from a more aggressive surgical therapy or an adjuvant therapy.

The effects of ruminally degraded protein on rumen fermentation and ammonia losses from manure in dairy cows

This experiment investigated the effect of dietary crude protein (CP) and ruminally degraded protein (RDP) levels on rumen fermentation, digestibility, ammonia emission from manure, and performance of lactating dairy cows. The experiment was a replicated 3 x 3 Latin square design with 6 cows. Three diets varying in CP concentration were tested (CP, % of dry matter): 15.4 (high CP, control), 13.4 (medium CP), and 12.9% (low CP). These diets provided metabolizable protein balances of 323, -44, and 40 g/d and RDP balances of 162, -326, and -636 g/d (high, medium, and low, respectively). Both the medium and low CP diets decreased ruminal pH compared with high CP, most likely because of the higher nonfiber carbohydrate concentration in the former diets. Ruminal ammonia pool size (rumen ammonia N was labeled with (15)N) and the concentration of total free amino acids were greater for the high CP diet than for the RDP-deficient diets. Apparent total-tract nutrient digestibilities were not affected by treatment. Both the medium and low CP diets resulted in lower absolute and relative excretion of urinary N compared with the high CP diet, as a proportion of N intake. Excretion of fecal N and milk yield and composition were not affected by diet. Milk N efficiency (milk N / N intake) and the cumulative secretion of ammonia-(15)N in milk protein were greater for the RDP-deficient diets, and milk urea N concentration was greater for the high CP diet. Both medium and low CP diets decreased the irreversible loss of ruminal ammonia N compared with the high CP diet. The rate and cumulative ammonia emissions from manure were lower for the medium and low CP diets compared with the high CP diet. Overall, this study demonstrated that dairy diets with reduced CP and RDP concentrations will produce manure with lower ammonia-emitting potential without affecting cow performance, if metabolizable protein requirements are met.

Up on the Jaynes-Cummings ladder of a quantum-dot/microcavity system

In spite of their different natures, light and matter can be unified under the strong-coupling regime, yielding superpositions of the two, referred to as dressed states or polaritons. After initially being demonstrated in bulk semiconductors and atomic systems, strong-coupling phenomena have been recently realized in solid-state optical microcavities. Strong coupling is an essential ingredient in the physics spanning from many-body quantum coherence phenomena, such as Bose-Einstein condensation and superfluidity, to cavity quantum electrodynamics. Within cavity quantum electrodynamics, the Jaynes-Cummings model describes the interaction of a single fermionic two-level system with a single bosonic photon mode. For a photon number larger than one, known as quantum strong coupling, a significant anharmonicity is predicted for the ladder-like spectrum of dressed states. For optical transitions in semiconductor nanostructures, first signatures of the quantum strong coupling were recently reported. Here we use advanced coherent nonlinear spectroscopy to explore a strongly coupled exciton-cavity system. We measure and simulate its four-wave mixing response, granting direct access to the coherent dynamics of the first and second rungs of the Jaynes-Cummings ladder. The agreement of the rich experimental evidence with the predictions of the Jaynes-Cummings model is proof of the quantum strong-coupling regime in the investigated solid-state system.

[Analysis of the statistical value of various commercially available stool tests - a comparison of one stool sample in correlation to colonoscopy]

INTRODUCTION

Guajac based fecal occult blood tests have proven to reduce mortality of colorectal cancer - despite their unsatisfactory statistical values. The potential of newer tests is yet inconclusive. We compared two guajac based, four immunochemical and the M2-PK test with colonoscopic and histological results as a reference.

METHODS

In 1128 stool samples of patients undergoing (screening) colonoscopy the mentioned tests were performed.

RESULTS

Positivity rate was 1.9 to 4.1 % for guajac based and immunochemical tests, M2-PK reached 11.6 %. In case of advanced neoplasias, no significant differences in sensitivity (7.3 - 20 %), specifity (96.6 - 98.4 %), positive predictive value (16.7 - 30.6 %) or accuracy (92.9 - 94.0 %) between guajac based and immunochemical tests were encountered. The slightly higher sensitivity of M2-PK (27.3 %) did not reach statistical significance - however the comparatively low specifity (89.2 %) and accuracy (86.2 %) were clearly lower compared to all other tests. Regarding all neoplasia, immunochemical tests performed better than conventional hemoccult, but the difference did not reach statistical significance. In this group, the sensitivity of M2-PK is clearly better, but specifity is clearly inferior to all other tests.

DISCUSSION

Low sensitivity and low predictive values are explained by the study design with single test and low prevalence of neoplasia. Due to small numbers, there is only a trend, but no significant difference between the performance of conventional hemoccult compared with immunochemical and high senstitive guajac tests. Because of its low specificity, M2-PK is not an appropriate screening test for colorectal neoplasia.

Single site-controlled In(Ga)As/GaAs quantum dots: growth, properties and device integration

Results obtained by an advanced growth of site-controlled quantum dots (SCQDs) on pre-patterned nanoholes and their integration into both photonic resonators and nanoelectronic memories are summarized. A specific technique has been pursued to improve the optical quality of single SCQDs. Quantum dot (QD) layers have been vertically stacked but spectrally detuned for single SCQD studies. Thereby, the average emission linewidth of single QDs could be reduced from 2.3 meV for SCQDs in a first QD layer close to the etched nanoholes down to 600 microeV in the third InAs QD layer. Accurate SCQD nucleation on large QD distances is maintained by vertical strain induced QD coupling throughout the QD stacks. Record narrow linewidths of individual SCQDs down to approximately 110 microeV have been obtained. Experiments performed on coupled photonic SCQD-resonator devices show an enhancement of spontaneous emission. SCQDs have also been integrated deterministically in high electron mobility heterostructures and flash memory operation at room temperature has been observed.

Direct observation of correlations between individual photon emission events of a microcavity laser

Lasers are recognized for coherent light emission, the onset of which is reflected in a change in the photon statistics. For many years, attempts have been made to directly measure correlations in the individual photon emission events of semiconductor lasers. Previously, the temporal decay of these correlations below or at the lasing threshold was considerably faster than could be measured with the time resolution provided by the Hanbury Brown/Twiss measurement set-up used. Here we demonstrate a measurement technique using a streak camera that overcomes this limitation and provides a record of the arrival times of individual photons. This allows us to investigate the dynamical evolution of correlations between the individual photon emission events. We apply our studies to micropillar lasers with semiconductor quantum dots as the active material, operating in the regime of cavity quantum electrodynamics. For laser resonators with a low cavity quality factor, Q, a smooth transition from photon bunching to uncorrelated emission with increasing pumping is observed; for high-Q resonators, we see a non-monotonic dependence around the threshold where quantum light emission can occur. We identify regimes of dynamical anti-bunching of photons in agreement with the predictions of a microscopic theory that includes semiconductor-specific effects.

The influence of the 5‐HT3receptor antagonist tropisetron on pain in fibromyalgia: a functional magnetic resonance imaging pilot study

OBJECTIVE

Central pain processing is altered in patients with fibromyalgia syndrome (FMS). The serotonin metabolism, especially the 5-HT3 receptor, seems to play an important role.

METHODS

We investigated the effect of the local injection of the 5-HT3 receptor antagonist tropisetron on the perception and central processing of pain in FMS patients using painful mechanical stimulation and functional magnetic resonance imaging (fMRI) within the framework of a pre-/posttreatment double-blind design.

RESULTS

In the contralateral primary somatosensory cortex, contralateral posterior insula, and anterior cingulate cortex, we found that the activation was significantly reduced after treatment. On average, patients rated the stimulation-induced pain intensity as stronger in the session after treatment compared to before treatment, although the individual data revealed a heterogeneous pattern. All patients showed sensitisation during the painful stimulation, which was not influenced by the treatment.

CONCLUSIONS

Both the sensory-discriminative and motivational-affective components of pain as measured by fMRI were altered by tropisetron.

Involvement of the PRKCB1 gene in autistic disorder: significant genetic association and reduced neocortical gene expression

Protein kinase C enzymes play an important role in signal transduction, regulation of gene expression and control of cell division and differentiation. The fsI and betaII isoenzymes result from the alternative splicing of the PKCbeta gene (PRKCB1), previously found to be associated with autism. We performed a family-based association study in 229 simplex and 5 multiplex families, and a postmortem study of PRKCB1 gene expression in temporocortical gray matter (BA41/42) of 11 autistic patients and controls. PRKCB1 gene haplotypes are significantly associated with autism (P<0.05) and have the autistic endophenotype of enhanced oligopeptiduria (P<0.05). Temporocortical PRKCB1 gene expression was reduced on average by 35 and 31% for the PRKCB1-1 and PRKCB1-2 isoforms (P<0.01 and <0.05, respectively) according to qPCR. Protein amounts measured for the PKCbetaII isoform were similarly decreased by 35% (P=0.05). Decreased gene expression characterized patients carrying the 'normal' PRKCB1 alleles, whereas patients homozygous for the autism-associated alleles displayed mRNA levels comparable to those of controls. Whole genome expression analysis unveiled a partial disruption in the coordinated expression of PKCbeta-driven genes, including several cytokines. These results confirm the association between autism and PRKCB1 gene variants, point toward PKCbeta roles in altered epithelial permeability, demonstrate a significant downregulation of brain PRKCB1 gene expression in autism and suggest that it could represent a compensatory adjustment aimed at limiting an ongoing dysreactive immune process. Altogether, these data underscore potential PKCbeta roles in autism pathogenesis and spur interest in the identification and functional characterization of PRKCB1 gene variants conferring autism vulnerability.