bluuebunny/crossref_metadata_2025 huggingface dataset:
Atmospheric Rivers and Rainfall during NASA’s Iowa Flood Studies (IFloodS) Campaign*
Authors: Nayak Munir A. , Villarini Gabriele , Bradley A. Allen
Published: September 2015

Atmospheric rivers (ARs) play a major role in causing extreme precipitation and flooding over the central United States (e.g., Midwest floods of 1993 and 2008). The goal of this study is to characterize rainfall associated with ARs over this region during the Iowa Flood Studies (IFloodS) campaign that took place in April–June 2013. Total precipitation during IFloodS was among the five largest accumulations recorded since the mid-twentieth century over most of this region, with three of the heavy rainfall events associated with ARs. As a preliminary step, the authors evaluate how well different remote sensing–based precipitation products captured the rainfall associated with the ARs and find that stage IV is the product that shows the closest agreement to the reference data. Two of the three ARs during IFloodS occurred within extratropical cyclones, with the moist ascent associated with the presence of cold fronts. In the third AR, mesoscale convective systems resulted in intense rainfall at many locations. In all the three cases, the continued supply of warm water vapor from the tropics and subtropics helped sustain the convective systems. Most of the rainfall during these ARs was concentrated within ~100 km of the AR major axis, and this is the region where the rainfall amounts were highly positively correlated with the vapor transport intensity. Rainfall associated with ARs tends to be larger as these events mature over time. Although no major diurnal variation is detected in the AR occurrences, rainfall amounts during nocturnal ARs were higher than for ARs that occurred during the daytime.
Pro-Environmental Change and Short- to Mid-Term Economic Performance
Authors: Rivera-Torres Pilar , Garcés-Ayerbe Concepción , Scarpellini Sabina , Valero-Gil Jesús
Published: September 2015

The aim of this study is to contribute empirically to the understanding of the economic effects of pro-environmental change in firms. First, we analyse whether pro-environmental changes performed in different sections of firms’ value chain (products, processes and supply and distribution channels) generate positive economic returns in the short- to mid-term. Second, we analyse whether measures implemented by firms to improve environmental performance (pro-environmental change) have been complemented with changes in organisational design, and whether these changes help increase short- to mid-term economic performance. Through an analysis of a sample of 303 firms, we have collected empirical evidence that confirms that pro-environmental change improves short- to mid-term business performance both directly and indirectly, through the mediating effect of improvements in organisational design that often go hand in hand with these processes.
Acute respiratory distress syndrome: does histology matter?
Authors: Lorente José A. , Ballén-Barragán Aida , Herrero Raquel , Esteban Andrés
Published: September 2015

Kao et al. have reported in Critical Care the histological findings of 101 patients with acute respiratory distress syndrome (ARDS) undergoing open lung biopsy. Diffuse alveolar damage (DAD), the histological hallmark of ARDS, was present in only 56.4 % of cases. The presence of DAD was associated with higher mortality. Evidence from this and other studies indicates that the clinical criteria for the diagnosis of ARDS identify DAD in only about half of the cases. On the contrary, there is evidence that the clinical course and outcome of ARDS differs in patients with DAD and in patients without DAD. The discovery of biomarkers for the physiological (increased alveolocapillary permeability) or histological (DAD) hallmarks of ARDS is thus of paramount importance.
The PFP and ESG protein function prediction methods in 2014: effect of database updates and ensemble approaches
Authors: Khan Ishita K. , Wei Qing , Chapman Samuel , KC Dukka B. , Kihara Daisuke
Published: September 2015

Background

Functional annotation of novel proteins is one of the central problems in bioinformatics. With the ever-increasing development of genome sequencing technologies, more and more sequence information is becoming available to analyze and annotate. To achieve fast and automatic function annotation, many computational (automated) function prediction (AFP) methods have been developed. To objectively evaluate the performance of such methods on a large scale, community-wide assessment experiments have been conducted. The second round of the Critical Assessment of Function Annotation (CAFA) experiment was held in 2013–2014. Evaluation of participating groups was reported in a special interest group meeting at the Intelligent Systems in Molecular Biology (ISMB) conference in Boston in 2014. Our group participated in both CAFA1 and CAFA2 using multiple, in-house AFP methods. Here, we report benchmark results of our methods obtained in the course of preparation for CAFA2 prior to submitting function predictions for CAFA2 targets.

Results

For CAFA2, we updated the annotation databases used by our methods, protein function prediction (PFP) and extended similarity group (ESG), and benchmarked their function prediction performances using the original (older) and updated databases. Performance evaluation for PFP with different settings and ESG are discussed. We also developed two ensemble methods that combine function predictions from six independent, sequence-based AFP methods. We further analyzed the performances of our prediction methods by enriching the predictions with prior distribution of gene ontology (GO) terms. Examples of predictions by the ensemble methods are discussed.

Conclusions

Updating the annotation database was successful, improving the Fmax prediction accuracy score for both PFP and ESG. Adding the prior distribution of GO terms did not make much improvement. Both of the ensemble methods we developed improved the average Fmax score over all individual component methods except for ESG. Our benchmark results will not only complement the overall assessment that will be done by the CAFA organizers, but also help elucidate the predictive powers of sequence-based function prediction methods in general.
Metabolome of human gut microbiome is predictive of host dysbiosis
Authors: Larsen Peter E. , Dai Yang
Published: September 2015

Background

Humans live in constant and vital symbiosis with a closely linked bacterial ecosystem called the microbiome, which influences many aspects of human health. When this microbial ecosystem becomes disrupted, the health of the human host can suffer; a condition called dysbiosis. However, the community compositions of human microbiomes also vary dramatically from individual to individual, and over time, making it difficult to uncover the underlying mechanisms linking the microbiome to human health. We propose that a microbiome's interaction with its human host is not necessarily dependent upon the presence or absence of particular bacterial species, but instead is dependent on its community metabolome; an emergent property of the microbiome.

Results

Using data from a previously published, longitudinal study of microbiome populations of the human gut, we extrapolated information about microbiome community enzyme profiles and metabolome models. Using machine learning techniques, we demonstrated that the aggregate predicted community enzyme function profiles and modeled metabolomes of a microbiome are more predictive of dysbiosis than either observed microbiome community composition or predicted enzyme function profiles.

Conclusions

Specific enzyme functions and metabolites predictive of dysbiosis provide insights into the molecular mechanisms of microbiome–host interactions. The ability to use machine learning to predict dysbiosis from microbiome community interaction data provides a potentially powerful tool for understanding the links between the human microbiome and human health, pointing to potential microbiome-based diagnostics and therapeutic interventions.
Direct association of visit-to-visit HbA1c variation with annual decline in estimated glomerular filtration rate in patients with type 2 diabetes
Authors: Takenouchi Akiko , Tsuboi Ayaka , Terazawa-Watanabe Mayu , Kurata Miki , Fukuo Keisuke , Kazumi Tsutomu
Published: September 2015

Background/Aims

This study examined associations of visit-to-visit variability of glycemic control with annual decline in estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes attending an outpatient clinic.

Methods

Intrapersonal mean and coefficient of variation (CV) of 8-12 measurements of HbA1c and those of 4-6 measurements of fasting and post-breakfast plasma glucose (FPG and PPG, respectively) during the first 12 months after enrollment were calculated in a cohort of 168 patients with type 2 diabetes. Annual changes in eGFR were computed using 52 (median) creatinine measurements obtained over a median follow-up of 6.0 years. Multivariate linear regressions assessed the independent correlates of changes in eGFR.

Results

CV-HbA1c (standardized β、-0.257、p = 0.004) were significantly and log urine albumin/creatinine ratio (standardized β、-0.155、p = 0.085) and smoking (standardized β、-0.186、p = 0.062) tended to be associated with annual eGFR decline independently of mean HbA1c, age, sex, BMI, waist circumference, diabetes duration and therapy, means and CVs of FPG, PPG and systolic blood pressure, baseline eGFR, and uses of anti-hypertensive and lipid-lowering medications. Association between HbA1c variability and renal function decline was stronger in patients with albumin/creatinine ratio ≧ 30 mg/g than in those with normoalbuminuria (r = -0.400, p = 0.003 and r = -0.169, p = 0.07, respectively).

Conclusions

Consistency of glycemic control is important to preserve kidney function in type 2 diabetic patients, in particular, in those with nephropathy.
Synthesis and Dynamic Structures of a Hybrid Nanohoop Molecule Composed of Anthanthrenylene and Phenylene Panels
Authors: Sarkar Parantap , Sato Sota , Kamata Sho , Matsuno Taisuke , Isobe Hiroyuki
Published: September 2015

A hybrid nanohoop molecule composed of anthanthrenylene and phenylene panels was synthesized. Structural analysis by NMR spectroscopy revealed the synchronous dynamics of the arylene panels in solution. Theoretical calculations further clarified the molecular structures involved in the dynamics and showed correlated rotations of neighboring arylene panels.
Inflammatory ulcera caused of vasculitides and vasculopathy
Authors: Kaisermayer E. S. , Daeschlein G. , Jünger M. , Lutze S.
Published: September 2015

In addition to traditional vascular causes ulceration of the lower leg as peripheral arterial disease and chronic venous insufficiency, it is primarily the vasculitis and vasculopathies, often are both diagnostically and therapeutically to a challenge.

The disorder group ranked in the frequency distribution of the causes of a leg ulcer with <10 % rarely in the area, but is much more complex of the pathogenesis, the clinical picture, the course of therapy and often much more complex.

The revised International in 2012 Chapel Hill Consensus Conference (CHCC) Nomenclature of vasculitis is a first impression of the diversity of this group of diseases and makes it clear how important the medical history for diagnosis is.

In the CHCC- categorizing the etiology, pathogenesis, the caliber of the vessel, the inflammatory type, the organs mainly affected, the clinical manifestation, genetic predisposition and demographic parameters were included.

With this revision of the first CHCC nomenclature of 1994 took place an important adaptation to the latest findings. The group of vasculitis is divided specific, this facilitates the handling of the disease in clinical practice.

The vasculopathies represent another rare fringe of the causes of an ulcer curis. These disorders are often as complex as a vasculitis and must be always used in difficult to treat ulcers in the differential diagnosis.
Comparative Analysis of Different Types Educational Institutions� Readiness for Teaching Pupils with Cerebral Palsy
Authors: �������  , Abkovich Alla , ��������  , Levchenko Irina
Published: September 2015

The article focuses on parents� and teachers� expert assessment of readiness of educational institutions to teach pupils with infantile cerebral palsy (ICP).

The authors identified special educational conditions necessary for successful education of ICP children and developed questionnaires to determine the

level of satisfying these conditions in three types of educational institutions. The questionnaires include questions on the following categories of special

conditions: barrier-free architectural environment and the availability of special technical equipment and devices for teaching; staff; software and methodological

support; medical support and recovery activities; psychological and pedagogical support and intervention work; provisions for orthopedic

treatment; cooperation with parents. Results of questioning allowed carrying out the monitoring of special educational conditions relying on Federal

State Educational Standard for pupils with limited health abilities. The article presents a comparative analysis of the survey among parents and teachers

of special schools for children with musculoskeletal disorders, secondary schools and schools of distance learning, which educate children with cerebral

palsy.
Matrix Approach to Modeling Pedagogical Objects in Didactic and Methodological Research
Authors: �������  , Monakhov V. , �����  , Erina T.
Published: September 2015

In the article, we talk about the technology of creating initial models of such pedagogical objects as educational process, methodological training system, and the trajectory of obtaining educational results required by Federal State Educational Standard. For further improvement of the initial model at the stage of in-model studies we suggest the technology of designing educational systems with given properties developed by V.M. Monakhov. We have also discussed the problem of algorithmically exact solutions of didactic tasks and problems.
On the Need to Prepare Teachers for Developing, Quality Assessing and System Activity Based Using Electronic Educational Resources
Authors: ��������  , Suvorova T.
Published: September 2015

The paper analyzes the status of development and application of electronic educational resources. The author discloses economic and psychologicalpedagogic

reasons for creating electronic educational resources with low didactic and consumer characteristics. For a more detailed review, the problem

of understanding between customers and developers of electronic educational resources is described. The author sees the way out of the situation in

using system-activity approach in developing requirements for electronic educational resources, and presents a number of arguments to justify the suitability

of applying this approach. The paper singles out basic directions of teachers� training for development, quality assessment and use of electronic

educational resources in contemporary processes of learning in information-educational environment.
Worm control in cattle: autumn and housing
Authors: Forbes Andrew
Published: September 2015

Grazing cattle face the risk of parasitic gastroenteritis and husk in the autumn. The magnitude of the risk depends on factors such as weather, grazing management, strategic use of anthelmintics and lungworm vaccination over the preceding months. Monitoring and vigilance are key components of helminth control in the autumn and, irrespective of conditions, effective anthelmintic treatment of cattle, especially youngstock, at housing can mitigate many of the adverse effects of parasites over winter.
Do they value education?
Authors: Sullivan Karen
Published: September 2015

How much do our students value their education, especially compared to others around the world? Karen Sullivan looks at tackling this question in class
Four steps to building your wellbeing
Authors: Stanley Julian
Published: September 2015

As a new school year begins, Julian Stanley looks at what steps you can take to manage your stress and support your wellbeing
AVALIAÇÃO DO ÍNDICE DE SOROPROTEÍNA NÃO DESNATURADA COMO UM INDICADOR DE TRATAMENTO TÉRMICO PARA LEITE UHT E LEITE EM PÓ
Authors: Oliveira Leandra Natália , Marinho Vanessa Toledo , Zamagno Marilana Vidal , Lauro Maraíse Aparecida , Barboza Jéssica Aparecida Norvino , Silva Paulo Henrique Fonseca da
Published: September 2015

Durante o processamento térmico de produtos lácteos ocorrem diversas modificações químicas dentre as quais a desnaturação de soroproteínas é bastante evidente e estudada. Este fenômeno pode gerar gelificação em leite UHT e problemas de solubilização em leite em pó, dois importantes produtos lácteos amplamente difundidos no mercado nacional. O índice de soroproteína não-desnaturada (WPNI) pode ser uma ferramenta útil para avaliar o grau de severidade ao qual o leite está sendo submetido e, portanto, permite inferir sobre a ocorrência dos possíveis defeitos associados à desnaturação proteica. Neste estudo, verificou-se o teor de soroproteína não-desnaturada como indicador de tratamento térmico em leite submetido aos processamentos de ultrapasteurização e de secagem. As amostras comerciais de leite UHT e leite em pó analisadas apresentaram um intervalo de confiança de WPNI (2,39 ± 1,41) mg WPN.mL-1 e (2,63 ± 1,38) mg WPN.mL-1, respectivamente. De acordo com a análise estatística de variância, todas as amostras avaliadas diferiram entre si com um p-valor < 0,001; sendo que 90% das amostras de leite UHT e 67% para as amostras de leite em pó foram classificadas como submetidas a médio tratamento térmico. Os dados obtidos permitiram inferir sobre a severidade do tratamento térmico associado a cada tipo de produto analisado e foram capazes de demonstrar a falta de padronização dos processos de tratamento térmico nas amostras estudadas, fato este que pode ter como consequência o desenvolvimento de características indesejáveis nos produtos ao longo do período de estocagem e comercialização.
IDENTIFICAÇÃO DE BACTÉRIAS PSICROTRÓFICAS PROTEOLÍTICAS ISOLADAS DE LEITE CRU REFRIGERADO E CARACTERIZAÇÃO DO SEU POTENCIAL DETERIORADOR
Authors: De Oliveira Pinto Cláudia Lúcia , Machado Solimar Gonçalves , Martins Maurilio Lopes , Dantas Vanetti Maria Cristina
Published: September 2015

Os objetivos deste estudo foram identificar bactérias psicrotróficas proteolíticas isoladas de leite cru refrigerado, avaliar o seu poder deteriorador e a sua capacidade de adesão em superfícies de aço inoxidável sob temperaturas de refrigeração. Dentre as bactérias gram-positivas, 23,81% e 33,33% dos isolados pertenciam aos gêneros Bacillus e Paenibacillus respectivamente. No grupo de bactérias gram-negativas fermentadoras de glicose foram identificados os gêneros Cedecea, Enterobacter, Hafnia, Klebsiella, Pantoea, Providencia, Rhanella e Serratia e dentre as bactérias gram-negativas não-fermentadoras, os gêneros Acinetobacter,Aeromonas, Burkholderia, Chryseobacteriun (Flavobacterium), Chryseomonas, Moraxella e Pseudomonas. O gênero Pseudomonas foi predominante entre as bactérias identificadas e representou 33,98% do total de isolados. Dentre as bactérias fermentadoras de glicose 14,6%, 15,3% e 20,8% dos isolados apresentaram predominantemente atividade proteolítica a 6,5 ºC, 21 ºC e 35 ºC, respectivamente, enquanto as bactérias gram-negativas não-fermentadoras apresentaram 25% e 23,6% dos isolados com atividades associadas de proteases, lipases e lecitinases a 6,5 ºC e 21 ºC, respectivamente, o que indicou maior potencial deteriorador. Em espécies de bactérias gram-negativas e gram-positivas, constatou-se a produção de enzimas termorresistentes e adesão à superfície de aço inoxidável a 6,5 ºC. Os resultados deste estudo reforçaram a importância da implementação das boas práticas de produção e de fabricação na cadeia produtiva do leite para fins de prevenção de sua deterioração e minimização de perdas de qualidade e econômicas.
Conceptualizing teacher professional identity in neoliberal times: Resistance, compliance and reform
Authors: Hall David , McGinity Ruth
Published: September 2015

This article examines the dramatic implications of the turn towards neo-liberal education policies for teachers’ professional identities. It begins with an analysis of some of the key features of this policy shift including marketization, metricization and managerialism and the accompanying elevation of performativity. This is followed by a discussion of the implications of this turn for teachers in which a new professionalism of increasing regulation and restrictions upon practice in a policy environment dominated by neo-liberalism act to restrict and confine professional identity formation and development. Drawing upon data collected within English schools the article explores how teachers have responded to this new policy environment in ways that are sensitive to how neo-liberal policy has been re-contextualized and re-translated in different educational settings. This reveals both the power of this New Right inspired permanent revolution of educational change in English schools and the complexities of how it has been variously embraced, accommodated and resisted by teachers. The article concludes with a discussion that explores the meaning of resistance in the context of what are identified as restricted teacher professional identities where affordances for professional practices lying outside of neo-liberal subjectivities have been dramatically reduced.
Training students to use syringe pumps: an experimental comparison of e-learning and classroom training
Authors: Grundgeiger Tobias , Kolb Lorenz , Korb Maximilian O. , Mengelkamp Christoph , Held Volker
Published: September 2015

The inadequate use of syringe pumps can jeopardize patient safety, and syringe pump trainings are conducted to manage this risk. A critical step in this risk management process is the learning success of trainees. In the present paper, we compared an e-learning approach with standard classroom training in learning success effectives, trainees’ opinion on the trainings, and investigated the relation between technological affinity and learning success. The results showed that e-learning was as effective as classroom training but nursing students’ confidence in using the pump and satisfaction with the training was decreased for e-learning compared with classroom training. We discuss the results in context of the nursing e-learning literature. Finally, we discuss the literature for risk identification, risk analysis, risk treatment, and risk monitoring and control in the context of syringe pump training and add the lessons learned from the evaluated e-learning program.
The development of an experimental setup to measure acousto-electric interaction signal
Authors: Kristín Inga Gunnlaugsdóttir
Published: September 2015

A new method is desirable for secure efficiency of FES treatment of degenerated denervated muscles. Degeneration of denervaed muscles as a consequence of spinal injuries are treated with functional electrical stimulation (FES). So far, no effective method to monitor the effectiveness of the treatment over the whole treated muscle is available. The most common method is placing finger on appropriate tendons and sense the movement. We suggest new approach. As pressure wave changes locally electrical conductivity in its propagation direction of the medium, a change in voltage is detected when electrical field is applied simultaneously at that location. This change in voltage is called acousto-electric interaction (AEI) signal. By recording AEI signal a distribution of electrical activity can be mapped, known as ultrasound current source density imaging (UCSDI). In this paper, an experimental setup to investigate the AEI signal is developed. The signal is measured and compared to calculated values. Debye effect and AEI signal is detected.
Field mapping of ballistic pressure pulse sources
Authors: Rad Abtin Jamshidi , Ueberle Friedrich
Published: September 2015

Ballistic pressure pulse sources are used since late 1990s for the extracorporeal treatment of chronic Enthesitis. Newly indications are found in trigger-point-therapy for the treatment of musculoskeletal disorders. In both applications excellent results without relevant side effects were found in clinical trials. The technical principle of pressure pulse source is based on the same techniques used in air guns. A projectile is accelerated by pressurized air and hits the applicator with high kinetic energy. By this a compression wave travels through the material and induces a fast (4..5μs), almost singular pressure pulse of 2..10 MPa, which is followed by an equally short rarefaction phase of about the same amplitude. It is assumed that the pressure pulse accounts for the biomedical effects of the device. The slower inertial motion of the waveguide is damped by elastic stoppers, but still can be measured several micro seconds after the initial pressure pulse. In order to characterize the pressure pulse devices, field mapping is performed on several radial pressure pulse sources using the fiber optic hydrophone and a polyvinylidenfluorid (PVDF) piezoelectric hydrophone. It could be shown that the current standard (IEC 61846) is not appropriate for characterization of ballistic pressure pulse sources.
Spike sorting: the overlapping spikes challenge
Authors: Sauer Inga , Doerr Christopher , Schanze Thomas
Published: September 2015

When recording action potentials (spikes) from many neurons simultaneously via multichannel micro-electrodes the overlapping of spikes from different neurons is a demanding problem for detection and classifi-cation of spikes (spike sorting). Since multichannel electrodes provide better possibilities to separate the superimposed waveforms, we refined an algorithm for separation of overlapping spikes for the use on multichannel recordings and tested it on simulated data with different numbers of signal channels and with several signal parameters. We show that the larger the number of signal channels the better the separation that may be achieved, especially under demanding recording conditions.
Compressed sensing of multi-lead ECG signals by compressive multiplexing
Authors: Tigges Timo , Sarikas Janis , Klum Michael , Orglmeister Reinhold
Published: September 2015

Compressed Sensing has recently been proposed for efficient data compression of multi-lead electrocardiogram recordings within ambulatory patient monitoring applications, e.g. wireless body sensor networks. However, current approaches only focus on signal reconstruction and do not consider the efficient compression of signal ensembles. In this work, we propose the utilization of a compressive multiplexing architecture that facilitates an efficient implementation of hardware compressed sensing for multi-lead ECG signals. For the reconstruction of ECG signal ensembles, we employ an greedy algorithm that exploits their joint sparsity structure. Our simulative study shows promising results which motivate further research in the field of compressive multiplexing for the acquisition multi-lead ECG signals.
Synchronization in wireless biomedical-sensor networks with Bluetooth Low Energy
Authors: Bideaux André , Zimmermann Bernd , Hey Stefan , Stork Wilhelm
Published: September 2015

Bluetooth Low Energy (BLE) has reduced the energy consumption for sensor nodes drastically. One major reason for this improvement is a non-continuous connection between the nodes. But this causes also a nondeterministic data transmission time. Most synchronization protocols are influenced by this characteristic, with the result of less accuracy. In wireless body sensor networks this accuracy is often of vital importance. Therefore this paper evaluates different synchronization principles customized for BLE.

For the evaluation measurements we used two BLE modules connected to one micro controller. This setup allowed us to calculate the error directly for the different principles. First we measured the send-receive time as a reference which influences most synchronization protocols. This time is directly affected by random transmission delays of BLE. Second we used the time difference between receiving and acknowledging a message as principle (A). The last principle (B) can only be used between nodes that use BLE that don’t require a constant connection, because it needs to connect and disconnect the nodes. After a new connection the “connected” events occur in the BLE nodes almost at the same time and can be used for synchronization. The reference measurement showed the worst results. The average delay was 4.76 ms with a standard deviation of 2.32 ms. Principle (A) showed average delays of 7.51 ms, which was almost exactly 1 connection interval in our setup. The standard deviation was 0.41 ms. Principle (B) showed the best results with an average time difference of 39.92 μs and a standard deviation of 14.19 μs

The results showed that with the principles (A) and (B) the synchronization of nodes can be highly improved compared to the reference. In future we will test the principles with synchronization protocols in real sensor nodes also with respect to the processor load.
Effects of sampling rate on automated fatigue recognition in surface EMG signals
Authors: Kahl Lorenz , Eger Marcus , Hofmann Ulrich G.
Published: September 2015

This study investigated the effects different sampling rates may produce on the quality of muscle fatigue detection algorithms. sEMG signals were obtained from isometric contractions of the arm. Subsampled signals resulting in technically relevant sampling rates were computationally deduced from the original recordings. The spectral based fatigue recognition methods mean and median frequency as well as spectral moment ratio were included in this investigation, as well as the sample and the fuzzy approximate entropy. The resulting fatigue indices were evaluated with respect to noise and separability of different load levels. We concluded that the spectral moment ratio provides the best results in fatigue detection over a wide range of sampling rates.
Metal artifact reduction by projection replacements and non-local prior image integration
Authors: Stille Maik , Thorsten Buzug M.
Published: September 2015

The presence of high-density objects remains an open problem in medical CT imaging. Data of projections that passing through such objects are dominated by noise. Reconstructed images become less diagnostically conclusive because of pronounced artifacts that manifest as dark and bright streaks. A new reconstruction algorithm is proposed, which incorporates information gained from a prior image. Based on a non-local regularization, these information are used to reduce streaking artifacts. In an iterative scheme, the prior image is transformed in order to match intermediate results of the reconstruction by solving a registration problem. During iterations, temporally appearing artifacts are reduced with a bilateral filter and projection values passing through high-density objects are replaced by new calculated values, which are used further on for the reconstruction. Results show that the proposed algorithm significantly reduces streaking artifacts.
Inkjet printing of viable human dental follicle stem cells
Authors: Mau Robert , Kriebel Katja , Lang Hermann , Seitz Hermann
Published: September 2015

Inkjet printing technology has the potential to be used for seeding of viable cells for tissue engineering approaches. For this reason, a piezoelectrically actuated, drop-on-demand inkjet printing system was applied to deliver viable human dental follicle stem cells (hDFSC) of sizes of about 15 μm up to 20 μm in diameter. The purpose of these investigations was to verify the stability of the printing process and to evaluate cell viability post printing. Using a Nanoplotter 2.1 (Gesim, Germany) equipped with the piezoelectric printhead NanoTip HV (Gesim, Germany), a concentration of 6.6 ×106 cells ml−1 in DMEM with 10% fetal calf serum (FCS) could be dispensed. The piezoelectric printhead has a nominal droplet volume of ~ 400 pl and was set to a voltage of 75 V and a pulse of 50 μs while dosing 50 000 droplets over a time of 100 seconds. The volume and trajectory of the droplet were checked by a stroboscope test right before and after the printing process. It was found that the droplet volume decreases significantly by 35% during printing process, while the trajectory of the droplets remains stable with only an insignificant number of degrees deviation from the vertical line. It is highly probable that some cell sedimentations or agglomerations affect the printing performance. The cell viability post printing was assessed by using the Trypan Blue dye exclusion test. The printing process was found to have no significant influence on cell survival. In conclusion, drop-on-demand inkjet printing can be a potent tool for the seeding of viable cells.
The use of an icebindingprotein out of the snowflea Hypogastrura harveyi as a cryoprotectant in the cryopreservation of mesenchymal stem cells
Authors: Vierthaler M. , Reinard T. , Glasmacher B. , Hofmann N.
Published: September 2015

Today researchers look for a possibility to keep cells for a long time without losing their viability. For that cryopreservation is often used. In this process it is necessary that the cells are not destroyed so cryoprotective agents (CPA) are needed. At the moment 5 to 10 % dimethylsulfoxide (DMSO) is mostly used, but this chemical is cytotoxic to the cells. So an alternative is needed. In this work experiments are made with an icebindingprotein (IBP) of Hypogastrura harveyi, as an alternative to DMSO. It was shown in previous studies that this protein isn’t cytotoxic for the cells, with crude extract and purified inclusion bodies it even seems that the mixtures have a positive effect on growth and proliferation. As a first step the protein was produced heterologous in E. coli and then the crude extract and the purified inclusion bodies were used for experiments on the influence of the IBP on the cryopreservation of mesenchymal stem cells from the common marmoset monkey Callithrix jacchus. In the process it was found that the protein could not replace DMSO completely. But it was possible to show that the DMSO-concentration can be reduced by adding the IBP.
QRS and QT ventricular conduction times and permanent pacemaker therapy after transcatheter aortic valve implantation
Authors: Takam P.C. , Höfflin D. , Heinke M.
Published: September 2015

Transcatheter aortic valve implantation is a therapy for patients with reduced left ventricular ejection fraction and symptomatic aortic stenosis. The aim of the study was to compare the pre-and post- transcatheter aortic valve implantation procedures to determine the QRS and QT ventricular conduction times as a potential predictor of permanent pacemaker therapy requirement after transcatheter aortic valve implantation. QRS and QT ventricular conduction times were prolonged after transcatheter aortic valve implantation in heart failure patients with permanent dual chamber pacemaker therapy after transcatheter aortic valve implantation. QRS and QT ventricular conduction times may be useful parameters to evaluate the risk of post-procedural ventricular conduction block and permanent pacemaker therapy in transcatheter aortic valve implantation.
Improving tactile sensation in laparoscopic surgery by overcoming size restrictions
Authors: Wiederer C. , Fröhlich M. , Strohmayr M.W.
Published: September 2015

Hepatic tumors appear as stiff inclusions within the surrounding soft, healthy tissue. In open surgery they are searched for by manual palpation with the gloved fingertip. However, to exploit the benefits of MIS it is mandatory to implement a substitution for the human sense of touch. Therefore, a tactile instrument has been developed with the aim of enlarging the sensing area at the tool tip once it enters the abdominal cavity through the trocar. The provision of a large sensitive surface enables the detection of nearly all sizes of tumors and decreases the time needed for the performance of this task. A prototype was manufactured by laser sintering in PA serving as a carrier for an existing flexible silicone sensor. Automated as well as manual subject palpation tests have shown that a prototypical instrument with a laterally opening lid would be a suitable device for tumor detection in laparoscopic liver surgery.
Evaluation of endourological tools to improve the diagnosis and therapy of ureteral tumors – from model development to clinical application
Authors: Wagner D. , Porsch M. , Detert M. , Bartel F. , Siedentopf S. , Schindele D. , Wendler JJ. , Lux A. , Schmidt B. , Schostak M. , Liehr UB.
Published: September 2015

Adequate diagnosis of upper urinary tract (UUT) tumors is essential for successful local treatment. Organsparing approaches are technically difficult and require consistent further development. Appropriate models for investigating new diagnostic and therapeutic methods are not yet available. This study demonstrates the incorporation of a fresh sample model into five different test levels (I-V) for improving the diagnosis and therapy of ureteral tumors. In these test levels, new diagnostic and ablation techniques are evaluated for feasibility, application safety, efficacy and accuracy. An assessment of their suitability for broad preclinical and clinical application also took economic aspects into account.
Frequency based assessment of surgical activities
Authors: Maktabi Marianne , Vinz Sascha T. , Neumuth Thomas
Published: September 2015

In hospitals the duration of surgeries plays a decisive role in many areas, such as patient safety or financial aspects. By utilizing accurate automated online prediction efficient surgical patient care and effective resource management can be attained. In this work several surgical activities during an intervention were examined for their potential to forecast the remaining intervention time. The method used was based on analysing in the frequency domain of time series which represented the status of surgical activities during an intervention. A nonparametric estimation of power spectral density was calculated for single surgical tasks during an intervention. The power spectral densities (PSD) of different surgical activities were compared in a leave-one-out cross validation of forty surgical workflow recordings of lumbar discectomies. The results showed that the activity irrigate with a mean prediction error of 26 min 23 s is best-suited for determining the remainder of the intervention. To construct a scheduling support for a wider range of surgery types the actions conducted by the surgeon’s right and left hand would eminently be more suitable; the error of the action right hand was 41 min 39 s, yet. In conclusion sophistication into the presented frequency based method might support time and resource management in a general manner.
Pseudo-haptic feedback in medical teleoperation
Authors: Neupert Carsten , Matich Sebastian , Pott Peter P. , Hatzfeld Christian , Werthschützky Roland
Published: September 2015

Pseudo-haptic feedback is a haptic illusion based on a mismatch of haptic and visual perception. It is well known from applications in virtual environments. In this work, we discuss the usabiliy of the principle of pseudo-haptic feedback for teleoperation. Using pseudo-haptic feedback can ease the design of haptic medical tele-operation systems.

Thereby a user’s grasping force at an isometric user interface is used to control the closing angle of an end effector of a surgical robot. To provide a realistic haptic feedback, the coupling characteristic of grasping force and end effector closing angle is changed depending on acting end effector interaction forces.

With an experiment, we show the usability of pseudo-haptic feedback for discriminating compliances, comparable to the mechanical characteristic of muscles relaxed and contracted. The provided results base upon the data of 10 subjects, and 300 trails.
Feasibility of interactive gesture control of a robotic microscope
Authors: Antoni Sven-Thomas , Sonnenburg Christian , Saathoff Thore , Schlaefer Alexander
Published: September 2015

Robotic devices become increasingly available in the clinics. One example are motorized surgical microscopes. While there are different scenarios on how to use the devices for autonomous tasks, simple and reliable interaction with the device is a key for acceptance by surgeons. We study, how gesture tracking can be integrated within the setup of a robotic microscope. In our setup, a Leap Motion Controller is used to track hand motion and adjust the field of view accordingly. We demonstrate with a survey that moving the field of view over a specified course is possible even for untrained subjects. Our results indicate that touch-less interaction with robots carrying small, near field gesture sensors is feasible and can be of use in clinical scenarios, where robotic devices are used in direct proximity of patient and physicians.
Integrating multimodal information for intraoperative assistance in neurosurgery
Authors: Eisenmann U. , Metzner R. , Wirtz C.R. , Dickhaus H.
Published: September 2015

Computer-assisted planning of complex neurosurgical interventions benefits from a variety of specific functions and tools. However, commercial planning- and neuronavigation systems are rather restrictive concerning the availability of innovative methods such as novel imaging modalities, fiber tracking algorithms or electrical dipole mapping. In this respect there is a demand for modular neurosurgical planning systems offering flexible interfaces for easy enhancement. Furthermore all relevant planning information should be available within neuron-avigation. In this work we present a planning system providing these capabilities and its suitability and application in a clinical setting. Our Multimodal Planning System (MOPS 3D) offers a variety of tools such as definition of trajectories for minimally invasive surgery, segmentation of ROIs, integration of functional information from atlas maps or magnetoencephalography. It also supplies plugin interfaces for future extensions. For intraoperative application MOPS is coupled with the neuronavigation system Brainlab Vector Vision Cranial/ENT (VVC). We evaluated MOPS in the Department of Neurosurgery at the University Hospital Heidelberg. Surgical planning and navigation was performed in 5 frequently occurring clinical cases. The time necessary for planning was between 5 and 15 minutes including data import, segmentation and planning tasks. The additional information intraoperatively provided by MOPS 3D was highly appreciated by the neurosurgeons and the performance was satisfactory.
Respiratory motion tracking using Microsoft’s Kinect v2 camera
Authors: Ernst Floris , Saß Philipp
Published: September 2015

In image-guided radiotherapy, monitoring and compensating for respiratory motion is of high importance. We have analysed the possibility to use Microsoft’s Kinect v2 sensor as a low-cost tracking camera. In our experiment, eleven circular markers were printed onto a Lycra shirt and were tracked in the camera’s color image using cross correlation-based template matching. The 3D position of the marker was determined using this information and the mean distance of all template pixels from the sensor. In an experiment with four volunteers (male and female) we could demonstrate that real time position tracking is possible in 3D. By averaging over the depth values inside the template, it was possible to increase the Kinect’s depth resolution from 1 mm to 0.1 mm. The noise level was reduced to a standard deviation of 0.4 mm. Temperature sensitivity of the measured depth values was observed for about 10-15 minutes after system start.
Experimental evaluation of different weighting schemes in magnetic particle imaging reconstruction
Authors: Szwargulski Patryk , Rahmer Jürgen , Ahlborg Mandy , Kaethner Christian , Buzug Thorsten M.
Published: September 2015

Magnetic Particle Imaging (MPI) is a new imaging technique with an outstanding sensitivity, a high temporal and spatial resolution. MPI is based on the excitation and detection of magnetic tracer material by using magnetic fields. The spatial resolution strongly depends on the reconstruction parameters and on the selection and weighting of the system function frequency components. Currently, no fundamental strategy to weight the system function for the reconstruction is given. In this contribution, the influence on the spatial resolution of different selection and weighting methods is analyzed. Thereby, a new strategy is proposed to select and weight the components with respect to their mixing order. As a result, it is confirmed that a weighted system function provides better results of image reconstruction than a non-weighted one. In addition to this, it is shown that the usage of the mixing order in combination with established weightings improves the resolution.
Intraoperative identification of somato-sensory brain areas using optical imaging and standard RGB camera equipment – a feasibility study
Authors: Oelschlägel M. , Meyer T. , Sobottka S. B. , Kirsch M. , Schackert G. , Morgenstern U.
Published: September 2015

Intraoperative Optical Imaging (IOI) is a neuro-imaging technique that allows the visualization of changes in optical properties of the brain cortex. Recent developments enhanced the method regarding the robustness under intraoperative conditions. However, the necessity of additional hardware still limits the use in the operating room (OR). Since modern surgical microscopes are potentially equipped with all required hardware for imaging, we investigated the possible use of such standard RGB camera for IOI. Measurements were performed on eight patients. Changes in optical properties of the cortical surface were acquired with a monochrome CCD camera (AxioCam MRm) and simultaneously with a standard RGB camera (Trio 610). Maps of cortical activity were calculated from the image data and the quality of these maps was assessed with a spatial signal-to-noise ratio. Activity maps calculated from AxioCam MRm data showed highest SNR in six out of eight patients. In two patients the activity map calculated from Trio 610 red channel performed best overall. The Trio 610 maps calculated from red channel data performed best in three out of eight cases like the activity maps calculated from green channel data, whereas the activity map calculated from blue channel data performed best in only two cases. If the color channel with the highest SNR is chosen in each patient for comparison to AxioCam MRm, the median of the SNR (SNR
AxioCam
/SNRBestColorChannel
) is 84 % (Quartile 1 (Q1): 78 %, Quartile 3 (Q3): 99%). Results reveal that the integration of the Intraoperative Optical Imaging method into the OR and surgical workflow can be further improved by using RGB camera equipment. A robust identification of somato-sensory areas seems possible. Due to the gain of information from different wavelength bands the need for intelligent evaluation algorithms is increased and should therefore be topic of future research.
Preliminary investigations of magnetic modulated nanoparticles for microwave breast cancer detection
Authors: Ley S. , Helbig M. , Sachs J.
Published: September 2015

This paper investigates the potential of magnetic modulated iron oxide nanoparticles in terms of a contrast enhancement for Ultra-wideband (UWB) breast imaging. The work is motivated by the low dielectric contrast between tumor and normal glandular/fibroconnective tissue. The influence of an external polarizing magnetic field on pure and coated magnetite nanoparticles is investigated in this contribution. Measurements were conducted using M-sequence UWB technology and an oil-gelatin phantom. It is shown that a coating, which is necessary for clinical use, results in a lower signal response, and thus leads to a lower detectability of magnetic modulated nanoparticles.