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Background: Laparoscopic cholecystectomy is a very frequent surgical procedure. However, in an ageing society, less surgical staff will need to perform surgery on patients. Collaborative surgical robots (cobots) could address surgical staff shortages and workload. To achieve context-awareness for surgeon-robot collaboration, the intraoperative action workflow recognition is a key challenge. Methods: A surgical process model was developed for intraoperative surgical activities including actor, instrument, action and target in laparoscopic cholecystectomy (excluding camera guidance). These activities, as well as instrument presence and surgical phases were annotated in videos of laparoscopic cholecystectomy performed on human patients (n= 10) and on explanted porcine livers (n= 10). The machine learning algorithm Distilled-Swin was trained on our own annotated dataset and the CholecT45 dataset. The validation of the model was conducted using a fivefold cross-validation approach. Results: In total, 22,351 activities were annotated with a cumulative duration of 24.9 h of video segments. The machine learning algorithm trained and validated on our own dataset scored a mean average precision (mAP) of 25.7% and a top K= 5 accuracy of 85.3%. With training and validation on our dataset and CholecT45, the algorithm scored a mAP of 37.9%. Conclusions: An activity model was developed and applied for the fine-granular annotation of laparoscopic cholecystectomies in two surgical settings. A machine recognition algorithm trained on our own annotated dataset and CholecT45 achieved a higher performance than training only on CholecT45 and can recognize frequently occurring activities well, but not infrequent activities.

Zusammenfassung: Die endovaskuläre Therapie des infrarenalen Bauchaortenaneurysmas hat sich als Alternative zur offenen chirurgischen Versorgung etabliert. Im Gegensatz zu Letzterer ist die Aneurysmatherapie mittels Stent-Grafts auch bei schwerkranken, nicht operationsfähigen Patienten möglich, wobei der Nutzen kontrovers diskutiert wird. Im Gegensatz zur klassischen transabdominellen Operation ist die Stent-Graft-Technik anatomischen Einschränkungen unterworfen, die aber künftig aufgrund bereits abzusehender technischer Weiterentwicklungen eine geringere Rolle spielen werden. Die Diagnostik, die Entscheidung für eine endovaskuläre Therapie, die präinterventionelle Planung und die Nachsorge erfordern den Einsatz bildgebender Verfahren, v. a. der Computer- und Magnetresonanztomographie sowie der Sonographie. Die für die endovaskuläre Aneurysmabehandlung relevanten Aspekte der Diagnostik werden dargestellt. Auf die Technik, die Materialien, die Ergebnisse und die Komplikationen der Stent-Graft-Behandlung wird ausführlich eingegangen.

Aims: The aim of this study was to investigate whether shifting the focus to solution orientation and developing coping strategies for common errors could increase the efficiency of laparoscopic training and influence learning motivation. The concept of coping has been particularly defined by the psychologist Richard Lazarus [Lazarus and Folkman in Stress, appraisal, and coping, Springer publishing company, New York, 1984]. Based on this model, we examined the use of observational learning with a coping model for its effectiveness as a basic teaching model in laparoscopic training. Methods: 55 laparoscopically naive medical students learned a standardized laparoscopic knot tying technique with video-based instructions. The control group was only offered a mastery video that showed the ideal technique and was free from mistakes. The intervention group was instructed on active error analysis and watched freely selectable videos of common errors including solution strategies (coping model) in addition to the mastery videos. Results: There was no statistically significant difference between the intervention and control groups for number of knot tying attempts until proficiency was reached (18.8 ± 5.5 vs. 21.3 ± 6.5, p= 0.142). However, there was a significantly higher fraction of knots achieving technical proficiency in the intervention group after first use of the coping model (0.7 ± 0.1 vs. 0.6 ± 0.2, p= 0.026). Additionally, the proportion of blinded attempts that met the criteria for technical proficiency was significantly higher for the intervention group at 60.9% vs. 38.0% in control group (p= 0.021). The motivational subscore “interest” of the validated score on current motivation (QCM) was significantly higher for the intervention group (p= 0.032), as well as subjective learning benefit (p= 0.002) and error awareness (p< 0.001). Conclusion: Using video-based learning of coping strategies for common errors improves learning motivation and understanding of the technique with a significant difference in its qualitative implementation in laparoscopy training. The ability to think in a solution-oriented, independent way is necessary in surgery in order to recognize and adequately deal with technical difficulties and complications.

Background:Online educational programs for nurse preceptors have been created based on various theoretical frameworks; however, no programs using a Strengths-Based Nursing (SBN) approach could be located. Purpose: This qualitative descriptive study explored the nurse preceptors’ experiences in using a SBN approach to provide clinical teaching to nursing students after completing an online SBN clinical teaching course. Methods:Semi-structured interviews were conducted with six nurses. Data was thematically analyzed. Findings: Although their levels of familiarity with SBN varied, all preceptors acknowledged that using a SBN approach in clinical teaching benefits both students and educators. They reported that it empowered students and that it allowed them to discover their strengths. Getting to know their students helped the preceptors provide tailored learning experiences and feedback. Using the SBN approach simultaneously enhanced the preceptors’ self-confidence and created opportunities for shared learning. Conclusion:Using a strengths’ approach offers nurse preceptors a powerful tool to facilitate student learning and skills development in clinical practice.

Background: Laparoscopic videos are increasingly being used for surgical artificial intelligence (AI) and big data analysis. The purpose of this study was to ensure data privacy in video recordings of laparoscopic surgery by censoring extraabdominal parts. An inside-outside-discrimination algorithm (IODA) was developed to ensure privacy protection while maximizing the remaining video data. Methods: IODAs neural network architecture was based on a pretrained AlexNet augmented with a long-short-term-memory. The data set for algorithm training and testing contained a total of 100 laparoscopic surgery videos of 23 different operations with a total video length of 207 h (124 min ± 100 min per video) resulting in 18,507,217 frames (185,965 ± 149,718 frames per video). Each video frame was tagged either as abdominal cavity, trocar, operation site, outside for cleaning, or translucent trocar. For algorithm testing, a stratified fivefold cross-validation was used. Results: The distribution of annotated classes were abdominal cavity 81.39%, trocar 1.39%, outside operation site 16.07%, outside for cleaning 1.08%, and translucent trocar 0.07%. Algorithm training on binary or all five classes showed similar excellent results for classifying outside frames with a mean F1-score of 0.96 ± 0.01 and 0.97 ± 0.01, sensitivity of 0.97 ± 0.02 and 0.0.97 ± 0.01, and a false positive rate of 0.99 ± 0.01 and 0.99 ± 0.01, respectively. Conclusion: IODA is able to discriminate between inside and outside with a high certainty. In particular, only a few outside frames are misclassified as inside and therefore at risk for privacy breach. The anonymized videos can be used for multi-centric development of surgical AI, quality management or educational purposes. In contrast to expensive commercial solutions, IODA is made open source and can be improved by the scientific community.

Five novel Eu(III)-β-diketonate complexes containing ruthenocene ancillary ligands (1,1′-bis(diphenylphosphoryl)ruthenocene─RcBPO) were synthesized and characterized. The coordination compounds presented the general formula [Eu(β-dik)3(RcBPO)], where β-dik stands for 2-thenoyltrifluoroacetonate (tta), 3-benzoyl-1,1,1-trifluoroacetone (btf), 2-dibenzoylmethanate (dbm), 2-acetyl-1,3-indandionate (aind), and 2-benzoyl-1,3-indandionate (bind), and RcBPO stands for 1,1′-bis(diphenylphosphoryl)ruthenocene. The [Eu(aind)3(RcBPO)] complex crystallizes in a monoclinic Cc non-centrosymmetric space group with the europium site environment, assuming a bicapped trigonal prism coordination polyhedron with the symmetry point group close to C2v. Photoluminescent properties for the solid-state samples were described in terms of excitation, emission, lifetime decay curves, and intrinsic and overall quantum yields. The replacement of the two coordinated H2O molecules by the RcBPO ancillary ligand leads to great enhancements of the overall quantum yields (QEuL), with the minimum increment by a factor of 5 for the case of [Eu(btf)3(RcBPO)] and the maximum enhancement of 270 times for the case of the [Eu(dbm)3(RcBPO)] complex. In addition, theoretical calculations were carried out to model the spectroscopic properties of the investigated compounds. To obtain theoretical Judd–Ofelt parameters (Ωλ, λ = 2, 4, and 6) and intramolecular energy transfer rates, the JOYSpectra web platform was employed using the structure obtained from density functional theory calculations. Hence, a rate equation model provided theoretical overall quantum yields, which are in great agreement with measured data.

The bacterial genus Tetrasphaeraencompasses abundant polyphosphate accumulating organisms (PAOs) that are responsible for enhanced biological phosphorus removal (EBPR) in wastewater treatment plants. Recent analyses of genomes from pure cultures revealed that 16S rRNA genes cannot resolve the lineage, and that Tetrasphaeraspp. are from several different genera within the Dermatophilaceae. Here, we examine 14 recently recovered high-quality metagenome-assembled genomes from wastewater treatment plants containing full-length 16S rRNA genes identified as Tetrasphaera, 11 of which belong to the uncultured Tetrasphaeraclade 3. We find that this clade represents two distinct genera, named here Ca. Phosphoribacter and Ca. Lutibacillus, and reveal that the widely used model organism Tetrasphaera elongatais less relevant for physiological predictions of this uncultured group. Ca. Phosphoribacter incorporates species diversity unresolved at the 16S rRNA gene level, with the two most abundant and often co-occurring species encoding identical V1-V3 16S rRNA gene amplicon sequence variants but different metabolic capabilities, and possibly, niches. Both Ca. P. hodrii and Ca. P. baldrii were visualised using fluorescence in situ hybridisation (FISH), and PAO capabilities were confirmed with FISH-Raman microspectroscopy and phosphate cycling experiments. Ca. Phosphoribacter represents the most abundant former Tetrasphaeralineage and PAO in EPBR systems in Denmark and globally.

Hintergrund: In den letzten Jahrzehnten hat ein massiver Wandel in der Chirurgie stattgefunden. Der moderne Operationssaal, insbesondere in der minimal-invasiven Chirurgie, zeichnet sich durch eine zunehmende Zahl digitaler Systeme aus. Ziel der Arbeit: In diesem Beitrag sollen aktuelle Entwicklungen sowie Perspektiven aufgezeigt werden, wie wir von der zunehmenden Digitalisierung im OP zu intelligenten, datengetriebenen Lösungen für die onkologische Chirurgie inklusive künstlicher Intelligenz (KI) kommen. Material und Methoden: Der Artikel basiert auf einer Literaturrecherche über PubMed und Forschungsarbeiten der beteiligten Koautoren. Ergebnisse: Datengetriebene Entscheidungsunterstützung umfasst aktuell vermehrt Publikationen, die chirurgisch-onkologische Daten mit maschinellen Lernverfahren verknüpfen. Die Integration von KI-Systemen in die Klinik, die bei klinisch relevanten Entscheidungen unterstützen, steht allerdings noch am Anfang. Diskussion: Zur Realisierung des skizzierten Potenzials wird dabei nicht nur eine engere Kooperation mit der Medizintechnikindustrie entscheidend sein, sondern vor allem auch der Aufbau translationaler, interdisziplinärer Laboratorien unter chirurgischer Leitung innerhalb chirurgischer Kliniken, die neue Innovationen aus der informatischen, datenwissenschaftlichen und robotischen Grundlagenforschung in die Klinik bringen.

The dependable guarantee of very high seam quality requirements in laser welding of demanding material combinations and highly stressed structures, such as powertrain components, is becoming increasingly important. The combination of sensor-based inline process monitoring and real-time data analysis using machine learning shows enormous potential for ensuring this. The subject of this paper is the assessment of process monitoring based on acoustic and optical sensor data by means of machine learning during laser welding on rotationally symmetric test specimens. The results show that typical welding defects caused by process variations can be detected with an accuracy of approx. 96 %, almost in real-time. Furthermore, approaches for predictive maintenance of system components and predictive modeling of component properties, supported by numerical simulations, are presented.

Background: The aim of this study was to assess the transferability of surgical skills for the laparoscopic hernia module between the serious game Touch Surgery™ (TS) and the virtual reality (VR) trainer Lap Mentor™. Furthermore, this study aimed to collect validity evidence and to discuss “sources of validity evidence” for the findings using the laparoscopic inguinal hernia module on TS. Methods: In a randomized crossover study, medical students (n= 40) in their clinical years performed laparoscopic inguinal hernia modules on TS and the VR trainer. TS group started with “Laparoscopic Inguinal Hernia Module” on TS (phase 1: Preparation, phase 2: Port Placement and Hernia Repair), performed the module first in training, then in test mode until proficiency was reached. VR group started with “Inguinal Hernia Module” on the VR trainer (task 1: Anatomy Identification, task 2: Incision and Dissection) and also performed the module until proficiency. Once proficiency reached in the first modality, the groups performed the other training modality until reaching proficiency. Primary endpoint was the number of attempts needed to achieve proficiency for each group for each task/phase. Results: Students starting with TS needed significantly less attempts to reach proficiency for task 1 on the VR trainer than students who started with the VR trainer (TS = 2.7 ± 0.6 vs. VR = 3.2 ± 0.7; p= 0.028). No significant differences for task 2 were observed between groups (TS = 2.3 ± 1.1 vs. VR = 2.1 ± 0.8; p= 0.524). For both phases on TS, no significant skill transfer from the VR trainer to TS was observed. Aspects of validity evidence for the module on TS were collected. Conclusion: The results show that TS brought additional benefit to improve performances on the VR trainer for task 1 but not for task 2. Skill transfer from the VR trainer to TS could not be shown. VR and TS should thus be used in combination with TS first in multimodal training to ensure optimal training conditions.

The bacterial genus Tetrasphaeraencompasses abundant polyphosphate accumulating organisms (PAOs) that are responsible for enhanced biological phosphorus removal (EBPR) in wastewater treatment plants. Recent analyses of genomes from pure cultures revealed that 16S rRNA genes cannot resolve the lineage, and that Tetrasphaeraspp. are from several different genera within the Dermatophilaceae. Here, we examine 14 recently recovered high-quality metagenome-assembled genomes from wastewater treatment plants containing full-length 16S rRNA genes identified as Tetrasphaera, 11 of which belong to the uncultured Tetrasphaeraclade 3. We find that this clade represents two distinct genera, named here Ca. Phosphoribacter and Ca. Lutibacillus, and reveal that the widely used model organism Tetrasphaera elongatais less relevant for physiological predictions of this uncultured group. Ca. Phosphoribacter incorporates species diversity unresolved at the 16S rRNA gene level, with the two most abundant and often co-occurring species encoding identical V1-V3 16S rRNA gene amplicon sequence variants but different metabolic capabilities, and possibly, niches. Both Ca. P. hodrii and Ca. P. baldrii were visualised using fluorescence in situ hybridisation (FISH), and PAO capabilities were confirmed with FISH-Raman microspectroscopy and phosphate cycling experiments. Ca. Phosphoribacter represents the most abundant former Tetrasphaeralineage and PAO in EPBR systems in Denmark and globally.

Extended dry storage of spent nuclear fuel is a relevant issue in many countries operating nuclear power plants. Beside regulatory and security aspects there are questions with respect to the long-term integrity of the spent fuel as this is of relevance for final transportation and reloading to final waste repository casks. Within the frame of the BMWi project DCS-MONITOR, we investigate the potentials of different methods for non-intrusive monitoring of dry cask storage containers with spent nuclear fuel. These are thermography, radiation-based methods, and acoustic methods. For all of them we study the sensitivity and cross-sensitivity with respect to defined changes in the nuclear fuel distribution inside the containers. The analyses are mainly based on numerical simulations but also include some dedicated experimental studies.

Supplemental Digital Content is available in the text.

Photoemission spectroscopy is central to understanding the inner workings of condensed matter, from simple metals and semiconductors to complex materials such as Mott insulators and superconductors1. Most state-of-the-art knowledge about such solids stems from spectroscopic investigations, and use of subfemtosecond light pulses can provide a time-domain perspective. For example, attosecond (10−18seconds) metrology allows electron wave packet creation, transport and scattering to be followed on atomic length scales and on attosecond timescales2–7. However, previous studies could not disclose the duration of these processes, because the arrival time of the photons was not known with attosecond precision. Here we show that this main source of ambiguity can be overcome by introducing the atomic chronoscope method, which references all measured timings to the moment of light-pulse arrival and therefore provides absolute timing of the processes under scrutiny. Our proof-of-principle experiment reveals that photoemission from the tungsten conduction band can proceed faster than previously anticipated. By contrast, the duration of electron emanation from core states is correctly described by semiclassical modelling. These findings highlight the necessity of treating the origin, initial excitation and transport of electrons in advanced modelling of the attosecond response of solids, and our absolute data provide a benchmark. Starting from a robustly characterized surface, we then extend attosecond spectroscopy towards isolating the emission properties of atomic adsorbates on surfaces and demonstrate that these act as photoemitters with instantaneous response. We also find that the tungsten core-electron timing remains unchanged by the adsorption of less than one monolayer of dielectric atoms, providing a starting point for the exploration of excitation and charge migration in technologically and biologically relevant adsorbate systems.

The time–energy information of ultrashort X-ray free-electron laser pulses generated by the Linac Coherent Light Source is measured with attosecond resolution via angular streaking of neon 1sphotoelectrons. The X-ray pulses promote electrons from the neon core level into an ionization continuum, where they are dressed with the electric field of a circularly polarized infrared laser. This induces characteristic modulations of the resulting photoelectron energy and angular distribution. From these modulations we recover the single-shot attosecond intensity structure and chirp of arbitrary X-ray pulses based on self-amplified spontaneous emission, which have eluded direct measurement so far. We characterize individual attosecond pulses, including their instantaneous frequency, and identify double pulses with well-defined delays and spectral properties, thus paving the way for X-ray pump/X-ray probe attosecond free-electron laser science. Attosecond time–energy characterization of pulses generated by the Linac Coherent Light Source (LCLS) X-ray free-electron laser is enabled by angular streaking measurements.

The downregulation of β-adrenergic receptors (β-AR) and decreased cAMP-dependent protein kinase activity in failing hearts results in decreased phosphorylation and inactivation of phosphatase-inhibitor-1 (I-1), a distal amplifier element of β-adrenergic signaling, leading to increased protein phosphatase 1 activity and dephosphorylation of key phosphoproteins, including phospholamban. Downregulated and hypophosphorylated I-1 likely contributes to β-AR desensitization; therefore its modulation is a promising approach in heart failure treatment. Aim of our study was to assess the effects of adeno-associated virus serotype 9 (AAV9) - mediated cardiac-specific expression of constitutively active inhibitor-1 (I-1c) and to investigate whether I-1c is able to attenuate the development of heart failure in mice subjected to transverse aortic constriction (TAC). 6-8 week old C57BL/6 N wild-type mice were subjected to banding of the transverse aorta (TAC). Two days later 2.8 × 1012AAV-9 vector particles harbouring I-1c cDNA under transcriptional control of a human troponin T-promoter (AAV9/I-1c) were intravenously injected into the tail vein of these mice (n=12). AAV9 containing a Renilla luciferase reporter (AAV9/hRluc) was used as a control vector (n=12). Echocardiographic analyses were performed weekly to evaluate cardiac morphology and function. 4 weeks after TAC pressure- volume measurements were performed and animals were sacrificed for histological and molecular analyses. Both groups exhibited progressive contractile dysfunction and myocardial remodeling. Surprisingly, echocardiographic assessment and histological analyses showed significantly increased left ventricular hypertrophy in AAV9/I-1c treated mice compared to AAV9/hRluc treated controls as well as reduced contractility. Pressure-volume loops revealed significantly impaired contractility after AAV9/I-1c treatment. At the molecular level, hearts of AAV9/I-1c treated TAC mice showed a hyperphosphorylation of the SR Ca2+-ATPase inhibitor phospholamban. In contrast, expression of AAV9/I-1c in unchallenged animals resulted in selective enhancement of phospholamban phosphorylation and augmented cardiac contractility. Our data suggest that AAV9-mediated cardiac-specific overexpression of I-1c, previously associated with enhanced calcium cycling, improves cardiac contractile function in unchallenged animals but failed to protect against cardiac remodeling induced by hemodynamic stress questioning the use of I-1c as a potential strategy to treat heart failure in conditions with increased afterload.

We report selected experimental results on the spin dynamics and spin freezing at ferromagnetic quantum phase transitions to illustrate some of the most prominent escape routes by which ferromagnetic quantum criticality is avoided in real materials. In the transition metal Heusler compound Fe2TiSn we observe evidence for incipient ferromagnetic quantum criticality. High pressure studies in MnSi reveal empirical evidence for a topological non-Fermi liquid state without quantum criticality. Single crystals of the hexagonal Laves phase compound Nb1−yFe2+yprovide evidence of a ferromagnetic to spin density wave transition as a function of slight compositional changes. Last but not least, neutron depolarisation imaging in CePd1−xRhxunderscore evidence taken from the bulk properties of the formation of a Kondo cluster glass.

In this study, the shape of the current pulse for shortpulse resistance spot welding (RSW) was investigated. In a companion study, it was shown through experiments and simulations that the welding time and total heat input could be reduced without a reduction in final weld size for the resistance spot welding of aluminum alloy AA6016-T4 using medium-frequency direct current (MFDC) welding systems. This study used a variation in current upslope time to vary the current pulse shape, and it used experiments and simulations to analyze the effect of heat input rate on the welding result. Experimental tests were performed on thin sheets (e.g., 1 to 2 mm or 0.04 to 0.08 in.) of AA6016-T4. The size and quality of the welds were evaluated by pull-out testing, ultrasound, and metallography. Resistance and electrode position profiles were evaluated through in-line parameter measurements. An increase in heat input rate was shown to reduce the current level necessary for welding nugget formation and decrease scatter in nugget size for low sheet thicknesses, resulting in a higher process stability. Additionally, significant time and energy savings in comparison to standard practices were obtained. Through an optimized current pulse shape and welding time, the short-pulse MFDC RSW technique can both reduce the current level and overall heat input requirements for satisfactory weld results for this alloy. [ABSTRACT FROM AUTHOR]

Short-pulse welding parameters for resistance spot welding (RSW) of aluminum alloy AA6016-T4 using medium-frequency direct current (MFDC) systems were developed to reduce the heat input required for nugget formation. Optimization of current and time parameters is critical during RSW of aluminum alloys for reducing energy requirements and avoiding weld imperfections, such as solidification cracking and expulsion, while maintaining weld quality, particularly given the high electrical and thermal conductivities of the materials. The welding time and the applied current level of the current pulse were varied systematically for thin sheets (1 mm or 0.04 in.) of AA6016-T4. The quality of the welds was evaluated by pull-out testing, ultrasound testing, and metallography techniques. Simulations of the same welding processes were performed with the finite element-based SORPAS® software. The results showed short-pulse MFDC RSW can reduce the energy required for sound welds in this alloy without requiring an increase in welding current. The simulations and experiments also showed the welding process had distinct weld nugget nucleation and growth phases. [ABSTRACT FROM AUTHOR]