MyHealthFrame - design and evaluation of a minimally invasive communication platform for telemedicine services aimed at older adults

MyHealthFrame is a communication platform that telemedicine (and well-being) services can leverage to deliver motivational messages and notifications to their end-users. Instead of being a telemedicine service in itself, MyHealthFrame is a channel through which external services can reach their users to provide reminders or deliver simple information such as number of steps. To its end-users, MyHealthFrame is a tablet device which is designed to be perceived as a photoframe and can be immersed in the users’ living environment. In this paper, we describe the design and the preliminary assessment of the platform. The results of the feasibility study with five older adults (65+) are promising

The STELLA Robotic Observatory on Tenerife

The Astrophysical Institute Potsdam (AIP) and the Instituto de Astrofísica de Canarias (IAC) inaugurated the robotic telescopes STELLA-I and STELLA-II (STELLar Activity) on Tenerife on May 18, 2006. The observatory is located on the Izaña ridge at an elevation of 2400 m near the German Vacuum Tower Telescope. STELLA consists of two 1.2 m alt-az telescopes. One telescope fiber feeds a bench-mounted high-resolution echelle spectrograph while the other telescope feeds a wide-field imaging photometer. Both scopes work autonomously by means of artificial intelligence. Not only that the telescopes are automated, but the entire observatory operates like a robot, and does not require any human presence on site

Usability of Three-dimensional Augmented Visual Cues Delivered by Smart Glasses on (Freezing of) Gait in Parkinson’s Disease

External cueing is a potentially effective strategy to reduce freezing of gait (FOG) in persons with Parkinson’s disease (PD). Case reports suggest that three-dimensional (3D) cues might be more effective in reducing FOG than two-dimensional cues. We investigate the usability of 3D augmented reality visual cues delivered by smart glasses in comparison to conventional 3D transverse bars on the floor and auditory cueing via a metronome in reducing FOG and improving gait parameters. In laboratory experiments, 25 persons with PD and FOG performed walking tasks while wearing custom-made smart glasses under five conditions, at the end-of-dose. For two conditions, augmented visual cues (bars/staircase) were displayed via the smart glasses. The control conditions involved conventional 3D transverse bars on the floor, auditory cueing via a metronome, and no cueing. The number of FOG episodes and percentage of time spent on FOG were rated from video recordings. The stride length and its variability, cycle time and its variability, cadence, and speed were calculated from motion data collected with a motion capture suit equipped with 17 inertial measurement units. A total of 300 FOG episodes occurred in 19 out of 25 participants. There were no statistically significant differences in number of FOG episodes and percentage of time spent on FOG across the five conditions. The conventional bars increased stride length, cycle time, and stride length variability, while decreasing cadence and speed. No effects for the other conditions were found. Participants preferred the metronome most, and the augmented staircase least. They suggested to improve the comfort, esthetics, usability, field of view, and stability of the smart glasses on the head and to reduce their weight and size. In their current form, augmented visual cues delivered by smart glasses are not beneficial for persons with PD and FOG. This could be attributable to distraction, blockage of visual feedback, insufficient familiarization with the smart glasses, or display of the visual cues in the central rather than peripheral visual field. Future smart glasses are required to be more lightweight, comfortable, and user friendly to avoid distraction and blockage of sensory feedback, thus increasing usability

Cimicifugae rhizoma: Phytoanalytical characterisation of cultivated plants and development of alternative control methods

Die Basis dieser Arbeit bildete ein umfangreicher Probensatz von am Albrecht Daniel Thaer-Institut der Humboldt Universität zu Berlin im Zeitraum von 2002–2014 kultivierten Einzelpflanzen von Actaea racemosa (L.) (Ranunculaceae) und anderen Actaea spp. Der Probensatz bestand aus vegetativ vermehrten Pflanzen – sogenannten Klonen – und Pflanzen unterschiedlicher Herkunft, z. B. aus Botanischen Gärten, von Universitäten oder Staudengärtnereien in Europa und den USA. Die Pflanzen sind unter einheitlichen Wachstumsbedingungen kultiviert und im Herbst 2014 gleichzeitig geerntet worden. Der pharmazeutisch genutzte Pflanzenteil ist das Rhizom (Cimicifugae rhizoma). Die Rhizome der in Berlin geernteten Exemplare wurden gemeinsam mit Mischchargen aus kommerziellem Anbau bzw. Wildsammlungen sowie Einzelexemplaren aus Wildsammlungen phytoanalytisch untersucht. Verschiedene Aspekte standen dabei im Fokus. Zum einen wurde untersucht, wie homogen genetisch einheitliches Material im Hinblick auf wertbestimmende Inhaltsstoffe ist. Ebenso wurden in Berlin kultivierte Einzelexemplare von A. racemosa verschiedener Herkunft im Hinblick auf Polyphenol- und Triterpenglykosidmuster charakterisiert. Der zweite Aspekt dieser Arbeit war die Entwicklung alternativer analytischer Verfahren zur Prüfung auf Identität und Substitution von C. rhizoma. Vor dem Hintergrund immer aufwändigerer neuer Verfahren wie dem Metabolic Fingerprinting oder dem DNA-Barcoding wurde untersucht, ob auch gängige, bereits in Routinelaboren etablierte Verfahren wie UV/VIS-Spektroskopie, NIR- Spektroskopie oder HPLC/DAD geeignet sind, ebensolche Prüfung zu ermöglichen. Zu diesem Zweck wurden sie an multivariate Analyseverfahren gekoppelt. Der dritte Aspekt dieser Arbeit betraf die Quantifizierung wertbestimmender Inhaltsstoffe in C. rhizoma mittels NIR-Spektroskopie. Die verschiedenen Klonpflanzen zeigten Schwankungen an Gehalten von Fukinolsäure und Acetylshengmanolxylosid – als prominenteste Vertreter der beiden Inhaltsstoffgruppen Polyphenole und Triterpenglykoside – von 11,5–13,3 % bzw. 8,0–17,0 % und lagen damit geringfügig über bzw. auf dem Niveau der Schwankung innerhalb ein und desselben Rhizoms mit jeweils 13,3 % bzw. 5,7 %. Die Gehalte derselben Verbindungen schwankten in den in Berlin kultivierten, genetisch uneinheitlichen Exemplaren (n = 101) um 37,8 % bzw. 42,4 %. In Handelsware aus Wildsammlungen (n = 6) schwankten entsprechende Gehalte um 33,9 % bzw. 26,3 %. Starke Unterschiede ergaben sich vor allem im Vergleich der Pflanzen aus Wildsammlungen und aus Kultur im Hinblick auf den Gesamtgehalt an Triterpenglykosiden, der in ersteren im Mittel bei > 1,1 %, in letzteren bei < 0,5 % lag. Diskutiert wird in diesem Zusammenhang der Einfluss der Wachstumsbedingungen bzw. der Einfluss der Wachstumsgeschwindigkeit. Für den Gehalt an Polyphenolen wurden allerdings keine großen Unterschiede in C. rhizoma verschiedener Herkunft gefunden. Im Hinblick auf Triterpenglykosid- Fingerprints wurden daher weiterhin Chemotypen postuliert, da bestimmte Muster sowohl bei Exemplaren aus Kultur als auch aus Wildsammlungen auftraten. Die UV /VIS-Spektroskopie, die NIR-Spektroskopie sowie die HPLC/UV konnten erfolgreich zur Abgrenzung von nah verwandten asiatischen und einer nordamerikanischen Actaea sp. und A. racemosa herangezogen werden. Ein auf Linearer Diskriminanzanalyse (LDA) basierendes multivariates Klassifizierungsmodell war in der Lage, die Zugehörigkeit einer Probe zu den Arten A. cimicifuga, A. cordifolia, A. heracleifolia, A. simplex und A. racemosa anhand von UV-Spektren eines Extrakts vorherzusagen. Ebenso konnten die Gehalte für Polyphenole in Rhizomen dieser verschiedenen Actaea spp. zu deren Unterscheidung herangezogen werden. In einer Hauptkomponentenanalyse (PCA) basierend auf diesen Daten zeigten sich separate Cluster der jeweiligen Arten. Weiterhin konnte die NIR-Spektroskopie o. g. asiatische Arten von den nordamerikanischen abgrenzen. Zusätzlich war die NIR-Spektroskopie in der Lage, C. rhizoma Handelsware von den in Berlin kultivierten Exemplaren zu unterscheiden. Basierend auf Referenzdaten für Polyphenole und Triterpenglykoside in C. rhizoma aus LC/DAD bzw. /ELSD wurden mittels PLS- Regression Vorhersagemodelle für Quantifizierung dieser Inhaltsstoffgruppen sowie Einzelverbindungen mittels NIR-Spektroskopie etabliert. Unterschiede in der Güte der Vorhersagemodelle (Kreuzvalidierungen) ergaben sich je nach Qualität der Referenzdaten aus LC, dem absoluten Gehalt der zu quantifizierenden Verbindung in C. rhizoma und je nach Probenset. Für Polyphenole ergaben sich meist sehr gute bis gute Modelle für z. B. die Bestimmung des Gesamtgehalts in Klonpflanzen mit R2 = 0,98 und RPD = 7,61 oder einzelne Polyphenole (alle R2 ≥ 0,92). Die heterogenere Gruppe der kultivierten Exemplare verschiedener Herkunft zeigte R2 = 0,93 für den Gesamtgehalt, aber eine Modellentwicklung für einzelne Verbindungen war kaum möglich. Im gesamten Probenset (n = 163), bestehend aus Klonpflanzen, kultivierten Exemplaren und Mischchargen aus Wildsammlungen zeigten nur der Gesamtgehalt an Polyphenolen (R2 = 0,95 und RPD = 4,62) und die Summe von Cimicifugasäure A+B (R2 = 0,84 und RPD = 2,49) Korrelation. Aufgrund der geringen Gehalte (häufig < LOQ) an Triterpenglykosiden in den kultivierten Exemplaren konnten generell keine Modelle etabliert werden. Der Bestwert lag hier bei R2 = 0,86 für Acetylshengmanolxylosid in Klonpflanzen. Für die Handelsware aus Wildsammlungen mit ihren entsprechenden höheren Gehalten konnte allerdings ein vielversprechendes Modell auch für den Gesamtgehalt an Triterpenglykosiden (R2 0,93/RPD = 4,22) etabliert werden. Da hier allerdings nur sechs Proben mit einbezogen werden konnten, ist dieses Modell nicht als einsatzfähig zu betrachten. Weitere Untersuchungen sollten dahingehend angestellt werden.This work is based on a large sample set of Actaea racemosa (L.) rhizomes (Cimicifugae rhizoma). The source plants have been cultivated in Berlin at the Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences in the years 2002–2014. The sample set consisted of genetically identical plants derived by vegetative propagation (clone plants), as well as a collection from different origins, e.g. botanical gardens or perennial nurseries from Europe and the US. Furthermore, different Asian and North American Actaea spp. have been cultivated. This set of samples from cultivation in Berlin was extended by different other types of C. rhizoma, i.e. by mixed batches from wholesalers and individual plants – both from wild harvesting in the US – and mixed batches from commercial cultivation in Germany. Altogether, over 200 samples have been phytoanalytically characterised by different methods of modern pharmacognosy, such as LC, TLC, LC/MS, UV/VIS and NIR spectroscopy. We focussed on three different aspects during these studies. First, the cultivated specimens – especially the clone plants – were characterised with regards to their homogeneity in comparison to the plants from different origins. The plants from different origins were investigated for their patterns of polyphenols and triterpene glycosides. The cause of the plant’s differences was assumed in the genetic diversity within the species A. racemosa, as they grew in the same environment. Secondly, this work focussed on development of alternative methods for species authentication. As recent methods get more and more sophisticated, e.g. metabolic fingerprinting or DNA- barcoding, we investigated simple and well-established methods. UV/VIS spectroscopy, HPLC, and NIR spectroscopy were coupled to multivariate analytical tools in order to make them capable of distinguishing different Actaea spp. from A. racemosa. Last, NIR spectroscopy was investigated for quantification of value determining compound classes in C. rhizoma. The different sets of clone plants showed a low variability (relative standard deviation) of content in fukinolic acid or acetylshengmanolxyloside – the two most prominent representative compounds for both major groups of constituents in C. rhizoma, polyphenols and triterpene glycosides – with 11.5–13.3 % and 8.0–17.0 %, respectively. This variability was only slightly higher as/at the level of the variability in one rhizome with each 13.3 % and 5.7 %. In contrast, both compounds varied by 37.8 % and 42.4 % in rhizomes of plants from different origins cultivated in Berlin. The mixed batches from wild showed a variability of only 33.9 % and 26.3 %, respectively. Rhizomes/batches from wild harvests showed generally higher total contents in triterpene glycosides (mean 1.1 %) in comparison to the plants from cultivation in Berlin (mean 0.5 %). An environmental influence and an influence of growth rate are discussed. Nevertheless, polyphenol contents were comparable within these groups of samples. For this reason, triterpene glycoside fingerprints were investigated. Different patterns of triterpene glycosides were found irrespectively of plant origin. Therefore, potential chemotypes of A. racemosa were proposed. UV/VIS spectroscopy, HPLC, and NIR spectroscopy were successfully applied to distinguish between different Asian and North American Actaea spp. and A. racemosa. UV/VIS spectroscopy coupled to the multivariate classification technique Linear Discriminant Analysis (LDA) was able to predict species membership for A. cimicifuga, A. cordifolia, A. heracleifolia, A. simplex and A. racemosa within the sample set of this study. Furthermore, genuine patterns of polyphenols in the species rhizomes – quantified by LC/DAD – could be used to distinguish those species. The species formed separate clusters in Principle Component Analysis (PCA) based upon polyphenol data. In addition, NIR spectroscopy was able to discriminate at least North American and Asian Actaea spp. from each other. NIR spectroscopy quantification of polyphenols and triterpene glycosides was investigated based upon reference data, determined by LC/DAD and LC/ELSD. Via Partial Least Squares Regression (PLSR) prediction models were built by correlating NIR spectra with reference data. Cross-validation was carried out. The quality of prediction models differed depending on the quality of reference data, the absolute content of the constituents in C. rhizoma, and the investigated sample subset. In general, model quality was good to very good for polyphenols, e.g. in clone plants alone with R2 = 0.98 and RPD = 7.61 for the total content or R2 ≥ 0.92 and RPD ≥ 3.45 even for individual polyphenols. The more heterogeneous group of plants from different origins, cultivated in Berlin showed R2 = 0.93 for the total content, but low to no correlation for individual polyphenols. Within the heterogeneous whole sample set (n = 163), only model development for determination of total content of polyphenols (R2 = 0.95 and RPD = 4.62) and sum of cimicifugic acids A+B (R2 = 0.84 and RPD = 2.49) was possible. Generally, NIRS quantification models could not be established for triterpene glycosides, as they showed low contents in cultivated C. rhizoma with total content under 0.5 % and many individual glycosides below LOQ. The maximum value was R2 = 0.86 for acetylshengmanolxyloside in clone plants. Nevertheless, the mixed batches from wild, with higher contents, showed promising correlation for the total content of triterpene glycosides (R2 = 0.93/RPD = 4.22). Only six batches were investigated in this case. Therefore, further studies should be conducted

In search of nano-materials with enhanced secondary electron emission for radiation detectors

There has been limited research devoted to secondary electron emission (SEE) from nano-materials using rapid and heavy ion bombardment. Here we report a comparison of SEE properties between novel nano-materials with a three-dimensional nano-structure composed of a mostly regular pattern of rods and gold used as a standard material for SEE under bombardment of heavy ions at energies of a few MeV/nucleon. The nano-structured materials show enhanced SEE properties when compared with gold. Results from this work will enable the development of new radiation detectors for science and industry

Usability of three-dimensional augmented visual cues delivered by smart glasses on (Freezing of) gait in parkinson's disease

External cueing is a potentially effective strategy to reduce freezing of gait (FOG) in persons with Parkinson's disease (PD). Case reports suggest that three-dimensional (3D) cues might be more effective in reducing FOG than two-dimensional cues. We investigate the usability of 3D augmented reality visual cues delivered by smart glasses in comparison to conventional 3D transverse bars on the floor and auditory cueing via a metronome in reducing FOG and improving gait parameters. In laboratory experiments, 25 persons with PD and FOG performed walking tasks while wearing custom-made smart glasses under five conditions, at the end-of-dose. For two conditions, augmented visual cues (bars/staircase) were displayed via the smart glasses. The control conditions involved conventional 3D transverse bars on the floor, auditory cueing via a metronome, and no cueing. The number of FOG episodes and percentage of time spent on FOG were rated from video recordings. The stride length and its variability, cycle time and its variability, cadence, and speed were calculated from motion data collected with a motion capture suit equipped with 17 inertial measurement units. A total of 300 FOG episodes occurred in 19 out of 25 participants. There were no statistically significant differences in number of FOG episodes and percentage of time spent on FOG across the five conditions. The conventional bars increased stride length, cycle time, and stride length variability, while decreasing cadence and speed. No effects for the other conditions were found. Participants preferred the metronome most, and the augmented staircase least. They suggested to improve the comfort, esthetics, usability, field of view, and stability of the smart glasses on the head and to reduce their weight and size. In their current form, augmented visual cues delivered by smart glasses are not beneficial for persons with PD and FOG. This could be attributable to distraction, blockage of visual feedback, insufficient familiarization with the smart glasses, or display of the visual cues in the central rather than peripheral visual field. Future smart glasses are required to be more lightweight, comfortable, and user friendly to avoid distraction and blockage of sensory feedback, thus increasing usability

Retaining traditionally hard to reach participants: Lessons learned from three childhood obesity studies

Retaining underserved populations, particularly low-income and/or minority participants in research trials, presents a unique set of challenges. In this paper, we describe the initial retention strategies and enhanced the retention strategies over time across three childhood obesity prevention trials. Hip-Hop to Health Jr. (HH) was a randomized controlled trial (RCT) testing a preschool-based obesity prevention intervention among predominately African-American children. Retention was 89% at 14-weeks, 71% at 1-year, and 73% at 2-year follow-up. Primary retention strategies for HH included: 1) collaboration with a community-based organization to enhance program credibility; 2) continuity of data collection locations; 3) collecting detailed contact information and provision of monetary compensation; and 4) developing a detailed tracking/search protocol. In a follow-up trial, Hip-Hop to Health Jr. Obesity Prevention Effectiveness Trial (HH Effectiveness), 95% of participants completed assessment at 14 weeks and 88% completed assessment at 1 year. For this trial, we emphasized staffing continuity in order to enhance participant relationship building and required data collection staff to have relevant community service experience. In a third study, we assessed dietary quality among participants in the Special Supplemental Nutrition Programfor Women, Infants, and Children (WIC) across three time points following the WIC food package shift instituted nationally in 2009. Retention rates were 91% at 12 months and 89% at 18 months. For our WIC\ study, we augmented retention by developing a home data collection protocol and increased focus on staff diversity training. We conclude with a summary of key strategies and suggestions for future research