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BackgroundOptimal bowel preparation is one of the major cornerstones for quality of colonoscopy. But poor bowel preparation still occurs in 10% to 25% of all patients. To optimize patient guidance, we developed a new smartphone app (ColoprAPP) for Android smartphones which guides and accompanies the patient starting 4 days before colonoscopy throughout the whole colonoscopy preparation procedure. ObjectiveThe objective of this study was to assess the function of a newly developed smartphone app for supporting colonoscopy preparation. MethodsWe carried out a prospective feasibility study including 25 patients undergoing outpatient colonoscopy at our hospital. As a control, we retrieved the data of 25 patients undergoing outpatient colonoscopy matching in age, sex, and indication for colonoscopy from our colonoscopy database. Patients were asked to download the smartphone app, ColoprAPP, in addition to being given the regular colonoscopy preparation leaflet. All colonoscopies were performed in the morning after using a split-dose preparation containing a polyethlene glycol–based purgative. The study was designed to test feasibility of the prototype, evaluate grade of bowel cleanliness (Boston bowel preparation scale [BBPS]), and assess patient satisfaction with the app. ResultsThe smartphone app use was feasible in all patients. BBPS count as a marker for grade of bowel preparation was significantly higher in the smartphone app–supported group (mean 8.1 [SD 0.3] vs 7.1 [SD 0.4], P=.02). Left (mean 2.8 [SD 0.1] vs 2.4 [SD 0.11], P=.02) and transverse colon (mean 2.8 [SD 0.07] vs 2.4 [SD 0.11], P

BackgroundIn gastroenterology a sufficient colon cleansing improves adenoma detection rate and prevents the need for preterm repeat colonoscopies due to invalid preparation. It has been shown that patient education is of major importance for improvement of colon cleansing. ObjectiveObjective of this study was to assess the function of an automated text messaging (short message service, SMS)–supported colonoscopy preparation starting 4 days before colonoscopy appointment. MethodsAfter preevaluation to assess mobile phone usage in the patient population for relevance of this approach, a Web-based, automated SMS text messaging system was developed, following which a single-center feasibility study at a tertiary care center was performed. Patients scheduled for outpatient colonoscopy were invited to participate. Patients enrolled in the study group received automated information about dietary recommendations and bowel cleansing during colonoscopy preparation. Data of outpatient colonoscopies with regular preparation procedure were used for pair matching and served as control. Primary end point was feasibility of SMS text messaging support in colonoscopy preparation assessed as stable and satisfactory function of the system. Secondary end points were quality of bowel preparation according to the Boston Bowel Preparation Scale (BBPS) and patient satisfaction with SMS text messaging–provided information assessed by a questionnaire. ResultsWeb-based SMS text messaging–supported colonoscopy preparation was successful and feasible in 19 of 20 patients. Mean (standard error of the mean, SEM) total BBPS score was slightly higher in the SMS group than in the control group (7.3, SEM 0.3 vs 6.4, SEM 0.2) and for each colonic region (left, transverse, and right colon). Patient satisfaction regarding SMS text messaging–based information was high. ConclusionsUsing SMS for colonoscopy preparation with 4 days’ guidance including dietary recommendation is a new approach to improve colonoscopy preparation. Quality of colonoscopy preparation was sufficient and patients were highly satisfied with the system during colonoscopy preparation.

The working environment of future university graduates is characterized by highly dynamic and complex product development processes. In addition to disciplinary competence, it is essential to build up methodical and social competence as well as to foster the elaboration and creativity potential of students. In order to meet industrial requirements the Karlsruhe Education Model for Product Development (KaLeP) was implemented. One element of this holistic education model is a design methods internship called ProVIL - Product Development in a Virtual Idea Laboratory. The above mentioned integrated understanding of product development and the competences derived from it are successfully taught in the case-based action learning environment ProVIL. Additionally, the very important aspect of multidisciplinary product development in site-distributed teams is taken into account and generates an added value to the progression of the KaLeP. In this work the authors present the dimensions of competence which should be aimed for a holistic teaching approach for the interdisciplinary student courses in ProVIL. An example illustrates how a continuous alignment and the necessary adaption of competences of student project teams can be achieved within ProVIL.

Intracortical brain-computer interfaces (iBCIs) have the potential to restore hand grasping and object interaction to individuals with tetraplegia. Optimal grasping and object interaction require simultaneous production of both force and grasp outputs. However, since overlapping neural populations are modulated by both parameters, grasp type could affect how well forces are decoded from motor cortex in a closed-loop force iBCI. Therefore, this work quantified the neural representation and offline decoding performance of discrete hand grasps and force levels in two human participants with tetraplegia. Participants attempted to produce three discrete forces (light, medium, hard) using up to five hand grasp configurations. A two-way Welch ANOVA was implemented on multiunit neural features to assess their modulation to force and grasp Demixed principal component analysis (dPCA) was used to assess for population-level tuning to force and grasp and to predict these parameters from neural activity. Three major findings emerged from this work: (1) force information was neurally represented and could be decoded across multiple hand grasps (and, in one participant, across attempted elbow extension as well); (2) grasp type affected force representation within multiunit neural features and offline force classification accuracy; and (3) grasp was classified more accurately and had greater population-level representation than force. These findings suggest that force and grasp have both independent and interacting representations within cortex, and that incorporating force control into real-time iBCI systems is feasible across multiple hand grasps if the decoder also accounts for grasp type.

Tekstą iš vokiečių kalbos vertė Antanas Gailius

Hybrid kinetic and kinematic intracortical brain-computer interfaces (iBCIs) have the potential to restore functional grasping and object interaction capabilities in individuals with tetraplegia. This requires an understanding of how kinetic information is represented in neural activity, and how this representation is affected by non-motor parameters such as volitional state (VoS), namely, whether one observes, imagines, or attempts an action. To this end, this work investigates how motor cortical neural activity changes when three human participants with tetraplegia observe, imagine, and attempt to produce three discrete hand grasping forces with the dominant hand. We show that force representation follows the same VoS-related trends as previously shown for directional arm movements; namely, that attempted force production recruits more neural activity compared to observed or imagined force production. Additionally, VoS-modulated neural activity to a greater extent than grasping force. Neural representation of forces was lower than expected, possibly due to compromised somatosensory pathways in individuals with tetraplegia, which have been shown to influence motor cortical activity. Nevertheless, attempted forces (but not always observed or imagined forces) could be decoded significantly above chance, thereby potentially providing relevant information towards the development of a hybrid kinetic and kinematic iBCI.

Decoders optimized offline to reconstruct intended movements from neural recordings sometimes fail to achieve optimal performance online when they are used in closed-loop as part of an intracortical brain-computer interface (iBCI). This is because typical decoder calibration routines do not model the emergent interactions between the decoder, the user, and the task parameters (e.g. target size). Here, we investigated the feasibility of simulating online performance to better guide decoder parameter selection and design. Three participants in the BrainGate2 pilot clinical trial controlled a computer cursor using a linear velocity decoder under different gain (speed scaling) and temporal smoothing parameters and acquired targets with different radii and distances. We show that a user-specific iBCI feedback control model can predict how performance changes under these different decoder and task parameters in held-out data. We also used the model to optimize a nonlinear speed scaling function for the decoder. When used online with two participants, it increased the dynamic range of decoded speeds and decreased the time taken to acquire targets (compared to an optimized standard decoder). These results suggest that it is feasible to simulate iBCI performance accurately enough to be useful for quantitative decoder optimization and design.

The evolution of the surface snow microstructure under the influence of wind during precipitation events is hardly understood but crucial for polar and alpine snowpacks. Available statistical models are solely parameterized from field data where conditions are difficult to control. Controlled experiments which exemplify the physical processes underlying the evolution of density or specific surface area (SSA) of surface snow under windy conditions are virtually non-existent. As a remedy, we conducted experiments in a cold laboratory using a ring-shaped wind tunnel with an infinite fetch to systematically investigate wind-induced microstructure modifications under controlled atmospheric, flow and snow conditions and to identify the relevant processes. Airborne snow particles are characterized by high-speed imaging, while deposited snow is characterized by density and SSA measurements. We used a single snow type (dendritic fresh snow) for simulating different precipitation intensities, varied wind speeds at a height of 0.4 m from 3 to 7 m s -1 (for fixed temperature) and varied temperatures from -24 to -2 °C (for fixed wind speed). The measured airborne impact trajectories confirm the consistency of our coefficient of restitution with large-scale saltation, rendering the setup suitable for realistically studying interactions between airborne and deposited snow. Increasing wind speeds resulted in intensified densification and stronger SSA decreases. The most drastic snow density and SSA changes in deposited snow are observed close to the melting point. Our measured densification rates as a function of wind speed show clear deviations from existing statistical models but can be re-parameterized through our data. This study, as a first of its kind, exemplifies a rich nonlinear interplay between airborne and deposited snow particles, which is discussed in view of a multitude of involved processes, i.e., airborne metamorphism, cohesion, particle separation and fragmentation. [ABSTRACT FROM AUTHOR]

ObjectiveBrain-computer interfaces (BCIs) can enable individuals with tetraplegia to communicate and control external devices. Though much progress has been made in improving the speed and robustness of neural control provided by intracortical BCIs, little research has been devoted to minimizing the amount of time spent on decoder calibration.ApproachWe investigated the amount of time users needed to calibrate decoders and achieve performance saturation using two markedly different decoding algorithms: the steady-state Kalman filter, and a novel technique using Gaussian process regression (GP-DKF).Main resultsThree people with tetraplegia gained rapid closed-loop neural cursor control and peak, plateaued decoder performance within 3 min of initializing calibration. We also show that a BCI-naïve user (T5) was able to rapidly attain closed-loop neural cursor control with the GP-DKF using self-selected movement imagery on his first-ever day of closed-loop BCI use, acquiring a target 37 s after initiating calibration.SignificanceThese results demonstrate the potential for an intracortical BCI to be used immediately after deployment by people with paralysis, without the need for user learning or extensive system calibration.

Background: Intervertebral disk (IVD) degeneration affects both humans and canines and is a major cause of low back pain (LBP). Mast cell (MC) and macrophage (MØ) infiltration has been identified in the pathogenesis of IVD degeneration (IVDD) in the human and rodent model but remains understudied in the canine. MC degranulation in the IVD leads to a pro‐inflammatory cascade and activates protease activated receptor 2 (PAR2) on IVD cells. The objectives of the present study are to: (1) highlight the pathophysiological changes observed in the degenerate canine IVD, (2) further characterize the inflammatory effect of MCs co‐cultured with canine nucleus pulposus (NP) cells, (3) evaluate the effect of construct stiffness on NP and MCs, and (4) identify potential therapeutics to mitigate pathologic changes in the IVD microenvironment. Methods: Canine IVD tissue was isolated from healthy autopsy research dogs (beagle) and pet dogs undergoing laminectomy for IVD herniation. Morphology, protein content, and inflammatory markers were assessed. NP cells isolated from healthy autopsy (Mongrel hounds) tissue were co‐cultured with canine MCs within agarose constructs and treated with cromolyn sodium (CS) and PAR2 antagonist (PAR2A). Gene expression, sulfated glycosaminoglycan content, and stiffness of constructs were assessed. Results: CD 31+ blood vessels, mast cell tryptase, and macrophage CD 163+ were increased in the degenerate surgical canine tissue compared to healthy autopsy. Pro‐inflammatory genes were upregulated when canine NP cells were co‐cultured with MCs and the stiffer microenvironment enhanced these effects. Treatment with CS and PAR2 inhibitors mediated key pro‐inflammatory markers in canine NP cells. Conclusion: There is increased MC, MØs, and vascular ingrowth in the degenerate canine IVD tissue, similar to observations in the clinical population with IVDD and LBP. MCs co‐cultured with canine NP cells drive inflammation, and CS and PAR2A are potential therapeutics that may mitigate the pathophysiology of IVDD in vitro. [ABSTRACT FROM AUTHOR]

The crush-leach technique is a frequently used method to determine the bulk composition of fluid inclusions trapped in a range of geological samples. We present a modified crush-leach technique combining ion chromatography (IC) and total reflection X-ray fluorescence spectroscopy (TXRF) which allows to determine a range of major, minor and trace elements out of one leachate. To date, trace element detection by means of TXRF is barely used in geosciences, although it combines the advantages of low to very low detection limits ([micro]g/L to ng/L range), small sample amount needed ([micro]L-range) and a fast and inexpensive analytical procedure. Previously described problems of adsorption of polyvalent cations at sample surfaces have been overcome by using acidified water as a leachate. Instead, it has been demonstrated that, for example, the syringe filter type used for IC measurements influences contamination and/or adsorption for a number of elements. The proposed method combination was evaluated for accuracy, reproducibility and system blanks and subsequently applied to quartz samples from hydrothermal vein deposits of the Schwarzwald ore district, SW Germany., Author(s): Sara Ladenburger [sup.1], Benjamin F. Walter [sup.1], Michael A. W. Marks [sup.1], Gregor Markl [sup.1] Author Affiliations: (1) grid.10392.39, 0000 0001 2190 1447, Fachbereich Geowissenschaften, Universität Tübingen, , 72074, [...]