bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transient supplementation of growth factor TGF-β1 effectively initiates chondrogenic redifferentiation of human chondrocytes
Authors: Hiemer Bettina , Achenbach Kathleen , Pasold Juliane , Wree Andreas , Bader Rainer 
Published: September 2017

Abstract
Cartilage tissue is avascular with less regeneration potential and therefore, cartilage regeneration is still a major challenge for therapeutic approaches. Commonly used treatment strategies involve the transplantation of autologous chondrocytes into the defect. Before that, it is required to increase the cell number in vitro resulting in unwanted chondrocyte dedifferentiation. This could impair subsequent tissue regeneration. Both growth factors TGF-ß1 and IGF-1 are used as strong inducer of chondrogenic redifferentiation, however, a controlled application of TGF-ß1 is essential to avoid adverse effects. Therefore, in the present study, we investigated the time-dependent influence of TGF-ß1 administration on chondrocyte redifferentiation.
Human chondrocytes were embedded in alginate and cultured in serum-free DMEM containing ascorbic acid, dexamethasone, ITSTM and IGF-1. TGF-β1 was supplemented for 3, 7 and 21 days. Afterwards, cell viability and synthesis of extracellular matrix (ECM) proteins was analyzed by histological staining.
Live/dead staining of chondrocytes incubated with TGF-β1 for 21 days displayed an enhanced proliferation and formation of cell clusters resulting in excessive outgrowth of fibroblastic-like cells. However, exposure to TGF-β1 over only 7 days caused also cell clustering with moderate cell proliferation. Additionally, after 21 days of cultivation proteoglycan synthesis was identified by alcian blue staining after both TGF-β1 supplementation for 21 and also 7 days. Aggrecan was also detected in the periphery of the cell clusters after TGF-β1 incubation for only 7 days. Chondrocytes lacked proteoglycan expression after three-day TGF-β1 administration.
We could show, that prolonged administration of TGF-β1 results in massive proliferation of chondrocytes which is accompanied by cell outgrowth. We found that TGF-ß1 exposure for seven days is sufficient for achievement of cell clustering without excessive cell proliferation, which is important for inducing subsequent chondrogenic differentiation. Results indicate that even an initial TGF-β1 administration could be sufficient for inducing chondrocyte proliferation and differentiation in vitro.
Myocardial T2
* mapping at ultrahigh magnetic fields: in vivo myocardial tissue characteri-zation and assessment of cardiac physiology with magnetic resonance imaging
Authors: Huelnhagen Till , Flemming Bert , Seeliger Erdmann , Schulz-Menger Jeanette , Niendorf Thoralf 
Published: September 2017

Abstract
Mapping the effective transverse relaxation time T2
* represents an emerging MRI tool for non-invasive myocardial tissue characterization and holds the promise to provide means for assessing myocardial (patho)physiology in vivo. This work takes advantage of the linear increase of susceptibility effects with magnetic field strength which renders it appealing to perform T2
* mapping at ultrahigh magnetic fields and enables temporally resolved T2
* mapping. Recognizing this potential this study examines the applicability of myocardial CINE T2
* mapping in healthy volunteers and hypertrophic cardiomyopathy (HCM) patients at 7.0 Tesla and investigates its capability to distinguish between healthy myocardium and myocardium affected by HCM.
Technical characterization of an 8 or 16 channel recording system to acquire electrocorticograms of mice
Authors: Englert Robert , Rupp Fabienne , Kirchhoff Frank , Koch Klaus Peter , Schweigmann Michael 
Published: September 2017

Abstract
When performing electrocorticography, reliable recordings of bioelectrical signals are essential for signal processing and analysis. The acquisition of cellular electrical activity from the brain surface of mice requires a system that is able to record small signals within a low frequency range. This work presents a recording system with self-developed software and shows the result of a technical characterization in combination with self-developed electrode arrays to measure electrocorticograms of mice.
Op-amp based low noise amplifier for magnetic particle spectroscopy
Authors: Malhotra Ankit , Buzug Thorsten 
Published: September 2017

Abstract
Magnetic particle spectrometry (MPS) is a novel technique used to measure the magnetization response of superparamagnetic iron oxide nanoparticles (SPIONs). Therefore, it is one of the most important tools for the characterization of the SPIONs for imaging modalities such as magnetic particle imaging (MPI) and Magnetic Resonance Imaging (MRI). In MPS, change in the particle magnetization induces a voltage in a dedicated receive coil. The amplitude of the signal can be very low (ranging from a few nV to 100 μV) depending upon the concentration of the nanoparticles. Hence, the received signal needs to be amplified with a low noise amplifier (LNA). LNA’s paramount task is to amplify the received signal while keeping the noise induced by its own circuitry minimum. In the current research, we purpose modeling, design, and development of a prototyped LNA for MPS. The designed prototype LNA is based on the parallelization technique of Op-amps. The prototyped LNA consists of 16 Op-amps in parallel and is manufactured on a printed circuit board (PCB), with a size of 110.38 mm × 59.46 mm and 234 components. The input noise of the amplifier is approx. 546 pV/√Hz with a noise figure (NF) of approx. 1.4 dB with a receive coil termination. Furthermore, a comparison between the prototyped LNA and a commercially available amplifier is shown.
Miniature CNT-based X-ray tube: assessment for use in intraoperative radiation therapy
Authors: Mahmoud-Pashazadeh Ali , Illanes Alfredo , Joseph Fredrick Johnson , van Oepen Alexander , Boese Axel , Friebe Michael 
Published: September 2017

Abstract
Carbon nanotube (CNT) is a new technology used to generate gamma photons in X-ray tubes. CNTs, in comparison to other small X-ray sources, produce high X-ray intensities and as they are not based on a thermionic principle they considered cold electron sources with a very high conversion of electrical to photon energy. Their small size and other interesting properties could make them feasible for use in intraoperative radiation therapy applications. In this study, physical characteristics of the photon beam generated by the CNT-based X-ray source were assessed. A soft X-ray ionization chamber and a flat panel detector was used to measure dose and photon counts, respectively. The repetitively produced pulses had almost the same photon intensities with differences of less than 1% between them. For a typical selected pulse, the variation in the pulse amplitude was also insignificant, which shows a stable radiation exposure of the tube during the ON-mode. When moving from the center of the beam profile to the lateral distance of 25 mm, both intensity profile and dose profile showed a falling trend by a factor of almost 3 in the measured values.
We also tested the miniature tube with our novel radiation beam shaping collimator designed for a possible application to treat larynx tumor, which showed the possibility of interventional radiation therapy using this miniature source. An endoscopic camera attached to the system can also make it possible to optically visualize the radiation exposed area.
In conclusion, CNT-based X-ray source with suitable attached collimator to shape the beam of the source, seems to provide an opportunity to deliver radiation to a desired tumor area in minimally invasive image guided medical procedures mainly in the normal cavities of the body.
Comparison of treatment plans calculated by Ray Tracing and Monte Carlo algorithms for head and thorax radiotherapy with Cyberknife
Authors: Galonske Kirsten , Thiele Martin , Ernst Iris , Lehrke Ralph , Zylka Waldemar 
Published: September 2017

Abstract
This study investigates differences between treatment plans generated by Ray Tracing (RT) and Monte Carlo (MC) calculation algorithms in homogeneous and heterogeneous body regions. Particularly, we focus on the head and on the thorax, respectively, for robotic stereotactic radiotherapy and radiosurgery with Cyberknife. Radiation plans for tumors located in the head and in the thorax region have been calculated and compared to each other in 47 cases and several tumor types.
Assuming MC as the algorithm of highest accuracy it is shown that based on selected dose parameters, RT slightly underestimates the dose in homogeneous regions and overestimates in heterogeneous regions. In addition, deviations occur due to tumor size rendering large differences for small tumors. We conclude that dose prescriptions for radiotherapy treatments should differentiate between RT and MC calculation algorithm. This is especially important for small tumors in heterogeneous body regions.
Analysis of the in-vivo GABAB receptor relocalization and oligomerization in chronic pain conditions using spatial intensity distribution analysis
Authors: Bienzeisler Jonas , Landry Marc , Llorente Alberto , Hüttmann Gereon 
Published: September 2017

Abstract
The response to the synaptic release of γ-Aminobutyric acid (GABA) in the central nervous system is mediated by the GABAB receptor, inter alia dependent on the formation of receptor oligomers. Spatial intensity distribution analysis (SpIDA) is an image analysis method measuring the oligomerization and density of proteins. It was used to quantify the oligomerization of GABAB receptors in the rodent spinal cord under conditions of chronic pain and inflammation. SpIDA reports a lowered density of tetrameric GABAB receptor entities in GABAergic neurons of the dorsal horn under these conditions compared to sham samples. The soma of neurons in the ventral horn is shown to be populated by single entities of the GABAB receptor. The findings underline the role of receptor oligomerization, as well as the membrane environment in regulating receptor function.
Fast care
Authors: Hoppstock Sabrina , Kußmann Peter , Fischer-Hirchert Ulrich H.P. 
Published: September 2017

Abstract
The project fast care is working on a real-time capable sensor data analysis-framework in the fields of "Ambient Assisted Living" (AAL), "Human-Technology Interaction" (MTI) and "eHealth". The aim is to provide a medical valid - integrated real-time picture of the patient’s situation by using an ad hoc interconnected sensor – actor infrastructure with a latency period of less than 10 ms.
Biomedical applications using magnetic nanoparticles-the SEON-concept
Authors: Alexiou Christoph 
Published: September 2017

Abstract
A multitude of different applications for magnetic nanoparticles were already investigated. Most prominent are drug delivery, imaging and several diagnostic in-vitro methods. To implement nanotechnological applications into clinics it is advantageous to cover all development stages starting from synthesis over characterization to the production of respective material under quality controlled conditions (cGMP)
Distance-dependent penumbra and MLC-width: new insights in determinants of healthy tissue sparing in stereotactic irradiation
Authors: Bratengeier Klaus , Wegener Sonja , Herzog Barbara 
Published: September 2017

Abstract
For stereotactic irradiation, both, penumbra and MLC leaf width make an impact on the sparing of healthy tissue around the target. Mostly, MLC design is regarded as the one influenceable parameter. However, also penumbra can be varied by choosing different distances between the source of radiation and the patient. The authors investigate the distance- dependent penumbra effects of idealized collimators as well as for real 5 mm MLCs. Test objects are small spherical targets of varying diameters to be irradiated under differing prescription conditions. A method to calculate exact stereotactic radial dose distributions from beam profiles or 2D dose distributions of single beams is developed for circular and MLC shaped targets. Also, a planning study is performed using a Pinnacle3™ planning system. Also, in a theoretical analysis perfect top hat profile beams and beams with varying penumbra are compared for better understanding of penumbra effects with respect to radial dose distributions. It is shown, that the penumbra changes for small targets are more relevant than the beam shaping by 5 mm MLCs. Quasi-isotropic irradiated MLC shaped (quadratic) beams at virtual SAD 700 mm produce steeper radial dose decrease than ideal circular beam shapes with a penumbra typical for SAD 1000 mm. A reduced source-to-patient distance allows better sparing of healthy tissue because of two reasons: The smaller effective leaf width but even more due to steeper penumbra. First, the authors suggest for future recommendations on stereotactic irradiations to specify not only MLC widths but also penumbra characteristics. Second, a so-called “virtual isocentre” could be useful to take advantage of the penumbra effect: Dependent on gantry angle and isocentric couch angle, the couch should be steered automatically in a way that the central axes of all beams always intersect in the same point at the same distance from the source.
Experimental and numerical investigations of fluid flow for optimized in vitro stem cell loading in xenografts
Authors: Ott Robert , Wüstenhagen Carolin , Martin Heiner , Stiehm Michael , Schmidt Wolfram , Einnolf Nadia , Frerich Bernhard , Grabow Niels , Schmitz Klaus-Peter , Siewert Stefan 
Published: September 2017

Abstract
In dentofacial surgery, augmentation procedures employing xenografts have become a reliable treatment. Recent studies, however, have shown significant enhance-ments of the in vivo bone tissue augmentation using mesenchymal stem cells loaded into bone grafts. We conducted experimental and numerical investigations in flow perfusion systems to determine flow conditions which allow for homogenous stem cell distribution in BioOss Block (Geistlich Pharma AG, Switzerland) xenografts. Pressure gradient-velocity characteristics and flow distributions were investigated experimentally and numerically at steady state flow conditions with Reynolds numbers (Re) ranging from 0.01 ≤ Re ≤ 0.40. Distilled water at 20°C with a dynamic viscosity of 1.002 mPa.s and a density of 998 kg/m3 was used. The geometry utilized in three-dimensional computa-tional fluid dynamics (CFD) simulation was obtained by means of micro-computed tomography (μCT). Results of CFD analysis are in good accordance with experimental data. The comparison of the pressure gradient-velocity characteris-tics for experimental and numerical data yields a relative error of 3.6%. According to Darcy’s law for creeping fluid flow the experimentally determined permeability is 2.55.10-9 m2. Moreover, numerical flow distribution analysis shows an increasingly heterogenic streamline distribution for increasing Reynolds numbers. Experimentally validated CFD simulations introduced in this study provide a tool to assess optimal flow conditions for a homogenous stem cell distribution in perfusion flow systems.
Estimation of the interpolation error of a three-step rotation algorithm using recorded images with rotated test pattern as ground truth
Authors: Dicke Elisa , Wachter Andreas , Nahm Werner 
Published: September 2017

Abstract
Nowadays, the surgical microscope is the goldstandard for microsurgical procedures. Additional functionalities such as surgical navigation, data injection or imageoverlay are providing additional valuable information to the surgeon. For substituting the conventional optical system by a fully-digital multi-camera setup the three dimensional (3D) reconstruction of the scenery in the field of view is required. However, for in camera-based systems, an exact alignment of the cameras is a challenging task. Therefore, a final adjustment through a digital image rotation becomes necessary. Even though the digital rotation is a commonly used procedure, it leads to unavoidable errors because of the discretized grid of the image. Previous research reported in literature has demonstrated that the method of digitally rotating the images combined with the Fourier interpolation delivers the results of best quality. Nevertheless, the performance evaluation of this algorithm was carried out rotating an image in multiple threestep rotations to a total of 90 or 180 degrees and comparing it to the original image rotated in one step. This is a valid approach because a rotation of 90 or 180 degrees does not produce rotation artifacts. In this research project, we verify the performance of the three-step rotation algorithm using recorded images for which the test pattern was rotated as ground truth. A series of photographs with a rotation angle of 3 to 45 degrees was created. The advantage of this setup is that the result of the digital rotation can be directly compared to the recorded image. In addition, with the knowledge obtained about the interpolation error, we can improve pixel matching in the further triangulation used for 3D reconstruction. By doing so, the estimation of the interpolation error helps to reduce the triangulation error.
Towards a better understanding of the overall health impact of the game of squash: automatic and high-resolution motion analysis from a single camera view
Authors: Brumann Christopher , Kukuk Markus 
Published: September 2017

Abstract
In this paper, we present a method for locating and tracking players in the game of squash using Gaussian mixture model background subtraction and agglomerative contour clustering from a calibrated single camera view. Furthermore, we describe a method for player re-identification after near total occlusion, based on stored color- and region-descriptors. For camera calibration, no additional pattern is needed, as the squash court itself can serve as a 3D calibration object. In order to exclude non-rally situations from motion analysis, we further classify each video frame into game phases using a multilayer perceptron. By considering a player’s position as well as the current game phase we are able to visualize player-individual motion patterns expressed as court coverage using pseudo colored heat-maps. In total, we analyzed two matches (six games, 1:28h) of high quality commercial videos used in sports broadcasting and compute high resolution (1cm per pixel) heat-maps. 130184 manually labeled frames (game phases and player identification) show an identification correctness of 79.28±8.99% (mean±std). Game phase classification is correct in 60.87±7.62% and the heat-map visualization correctness is 72.47±7.27%.
Counterfactual-Based Prevented and Preventable Proportions
Authors: Yamada Kentaro , Kuroki Manabu 
Published: September 2017

AbstractPrevented and preventable fractions have been widely used in medical science to evaluate the proportion of new diseases that can be averted by a protective exposure. However, most existing formulas used in practical situations cannot be interpreted as proportions without any further assumptions because they are obtained according to different target populations and may fall outside the range$[0.000,1.000]$. To solve this problem, this paper proposes counterfactual-based prevented and preventable proportions. When both causal effects and observed probabilities are available, we show that the proposed measures are identifiable under the negative monotonicity assumption. Additionally, when the negative monotonicity assumption is violated, we formulate the bounds on the proposed measures. We also show that negative monotonicity together with exogeneity induces equivalence between the proposed measures and existing measures.
Fabrication of porous polymeric structures using a simple sonication technique for tissue engineering
Authors: Álvarez-Suarez Alan Saúl , López-Maldonado Eduardo Alberto , Graeve Olivia A. , Martinez-Pallares Fabián , Gómez-Pineda Luis Enrique , Oropeza-Guzmán Mercedes Teresita , Iglesias Ana Leticia , Ng Theodore , Serena-Gómez Eduardo , Villarreal-Gómez Luis Jesús 
Published: September 2017

Abstract
Porous polymeric scaffolds have been applied successfully in the biomedical field. This work explores the use of an ultrasonic probe to generate cavitation in a polymeric solution, thus producing pores in the polymeric scaffolds. Porous polymeric structures with average pore sizes ranging from 5 to 63 μm and porosity of 6–44% were fabricated by a process consisting of sonication, flash freezing, and lyophilization of poly(lactic-co-glycolic acid) (PLGA), gelatin (GEL), chitosan (CS) and poly(vinyl alcohol) (PVAL) solutions. Pore structure was characterized by scanning electron microscopy (SEM) and image analysis software. The infrared spectra were analyzed before and after the fabrication process to observe any change in the chemical structure of the polymers. A water absorption test indicated the susceptibility of the samples to retain water in their structure. TGA results showed that GEL experienced degradation at 225°C, CS had a decomposition peak at 280°C, the thermal decomposition of PLGA occurred at 375°C, and PVAL showed two degradation regions. The DSC analysis showed that the glass transition temperature (Tg) of GEL, CS, PLGA and PVAL occurred at 70°C, 80°C, 60°C and 70°C, respectively. The fabricated porous structures demonstrated similar physical characteristics to those found in bone and cartilage.
Rafet Bey: The Last Ottoman Consul in Batavia during the First World War 1911-1924
Authors: Supratman Frial Ramadhan 
Published: September 2017

This paper will investigate a brief intellectual history of Rafet Bey, an Ottoman statesman who was appointed as consul-general in Batavia in the early twentieth century. In this paper, intellectual and global history will be the main approach to analyze relations between the Ottomans and the Dutch East Indies (Indonesia) in the early twentieth century, especially during the First World War. The appointment of Rafet Bey as Ottoman consul in Batavia coincided with a moment of strength for the Dutch East Indies, after conquering Aceh and other Indonesian regions. On the other hand, the emergence of the Armenian question also caused some difficulties in Ottoman foreign policy at the time. In short, a brief intellectual biography of Rafet Bey is important because it allows deeper analysis on Ottoman- Indonesia relations in the early twentieth century.DOI: 10.15408/sdi.v24i1.3684
Ṣuwar al-ḥaḍānah ba‘da al-ṭalāq fī Aceh al-Wusṭá
Authors: Fauzi Fauzi 
Published: September 2017

The divorce rate occurred in post-tsunami Aceh have increased sharply, especially in Central Aceh district by 2015. This research was conducted in order to figure out the causes of divorce, the patterns of ḥaḍānah (child custody) and the parent’s attention towards their children after the divorce. The selection of Central Aceh as the object of research was because this district has been occupying the highest position of divorce rate when compared to other districts/cities. The results of this study explain that divorce occurs due to love affairs, economic problems, third-party intervention, early marriage, lack of communication, having no trust and different views of life principles. Meanwhile the pattern of ḥaḍānah happened was mostly carried out by their mother, and the rest was taken care of by their father and the third party like their grandparents. The relationship between the cause of divorce and ḥaḍānah is that when divorce is caused by a spouse’s bickering usually has a negative effect on the pattern of ḥaḍānah, if the divorce happened due to disagreement in the life principles or a certain principle it would have a positive impact. This negative impact on certain conditions requires that older children bear the needs of their younger siblings.DOI: 10.15408/sdi.v24i1.4189