216 research outputs found
The impact of perceived privacy risks on organizations' willingness to share item-level event data acrossthesupply chain
When information is available about the path, on which individual items move through the real world, many beneficial applications can be designed. The necessary data can be generated through attaching identifiers to items and deploying suitable readers all over the supply chain that capture the information on the identifiers. Organizations only have access to data about item movements within their organizational boundaries. Therefore sharing of data between organizations is required to gain full visibility. However, the willingness of organizations to share data is considered to be low. In this paper we present the results of a study that aimed at investigating the actual willingness of companies to share item-level data and at exploring the perceived privacy risks that may restrain companies from sharing item-level data. From the findings, requirements for the design of inter-organizational data sharing infrastructures are derive
Air travel with pneumocephalus: a systematic review
Introduction: Concerns arise when patients with pneumocephalus engage in air travel. How hypobaric cabin pressure affects intracranial air is largely unclear. A widespread concern is that the intracranial volume could relevantly expand during flight and lead to elevated intracranial pressure. The aim of this systematic review was to identify and summarise models and case reports with confirmed pre-flight pneumocephalus.
Methods: The terms (pneumocephalus OR intracranial air) AND (flying OR fly OR travel OR air transport OR aircraft) were used to search the database PubMed on 30 November 2021. This search returned 144 results. To be included, a paper needed to fulfil each of the following criteria: (i) peer-reviewed publication of case reports, surveys, simulations or laboratory experiments that focussed on air travel with pre-existing pneumocephalus; (ii) available in full text.
Results: Thirteen studies met the inclusion criteria after title or abstract screening. We additionally identified five more articles when reviewing the references. A notion that repeatedly surfaced is that any air contained within the neurocranium increases in volume at higher altitude, much like any extracranial gas, potentially resulting in tension pneumocephalus or increased intracranial pressure.
Discussion: Relatively conservative thresholds for patients flying with pneumocephalus are suggested based on models where the intracranial air equilibrates with cabin pressure, although intracranial air in a confined space would be surrounded by the intracranial pressure. There is a discrepancy between the models and case presentations in that we found no reports of permanent or transient decompensation secondary to a pre-existing pneumocephalus during air travel. Nevertheless, the quality of examination varies and clinicians might tend to refrain from reporting adverse events. We identified a persistent extracranial to intracranial fistulous process in multiple cases with newly diagnosed pneumocephalus after flight. Finally, we summarised management principles to avoid complications from pneumocephalus during air travel and argue that a patient-specific understanding of the pathophysiology and time course of the pneumocephalus are potentially more important than its volume.
Keywords: Air travel; Flying; Intracranial air; Intracranial gas; Pneumocephalus
Mobile intraoperative CT-assisted frameless stereotactic biopsies achieved single-millimeter trajectory accuracy for deep-seated brain lesions in a sample of 7 patients
BACKGROUND
Brain biopsies are crucial diagnostic interventions, providing valuable information for treatment and prognosis, but largely depend on a high accuracy and precision. We hypothesized that through the combination of neuronavigation-based frameless stereotaxy and MRI-guided trajectory planning with intraoperative CT examination using a mobile unit, one can achieve a seamlessly integrated approach yielding optimal target accuracy.
METHODS
We analyzed a total of 7 stereotactic biopsy trajectories for a variety of deep-seated locations and different patient positions. After rigid head fixation, an intraoperative pre-procedural scan using a mobile CT unit was performed for automatic image fusion with the planning MRI images and a peri-procedural scan with the biopsy cannula in situ for verification of the definite target position. We then evaluated the radial trajectory error.
RESULTS
Intraoperative scanning, surgery, computerized merging of MRI and CT images as well as trajectory planning were feasible without difficulties and safe in all cases. We achieved a radial trajectory deviation of 0.97 ± 0.39 mm at a trajectory length of 60 ± 12.3 mm (mean ± standard deviation). Repositioning of the biopsy cannula due to inaccurate targeting was not required.
CONCLUSION
Intraoperative verification using a mobile CT unit in combination with frameless neuronavigation-guided stereotaxy and pre-operative MRI-based trajectory planning was feasible, safe and highly accurate. The setting enabled single-millimeter accuracy for deep-seated brain lesions and direct detection of intraoperative complications, did not depend on a dedicated operating room and was seamlessly integrated into common stereotactic procedures
Removal of mismatched bases from synthetic genes by enzymatic mismatch cleavage
The success of long polynucleotide de novo synthesis is largely dependent on the quality and purity of the oligonucleotides used. Generally, the primary product of any synthesis reaction is directly cloned, and clones with correct products have to be identified. In this study, a novel strategy has been established for removing undesired sequence variants from primary gene synthesis products. Single base-pair mismatches, insertions and deletions were cleaved with specific endonucleases. Three different enzymes—T7 endonuclease I, T4 endonuclease VII and Escherichia coli endonuclease V—have been tested. As a model, a synthetic polynucleotide encoding the bacterial chloramphenicol-acetyltransferase (cat) was synthesized using different methods for one step polynucleotide synthesis based on ligation of oligonucleotides. The influence of enzymatic mismatch cleavage (EMC) as an error correction step on the frequency of correct products was analyzed by functional cloning of the synthetic cat and comparing the error rate with that of untreated products. Significant reduction of all mutation types was observed. Statistical analysis revealed that the T4 and E.coli endonucleases reduced the occurrence of mutations in cloned synthetic gene products. The EMC treatment was successful especially in the removal of deletions and insertions from the primary ligation products
A Versatile Sensor Data Processing Framework for Resource Technology
Die Erweiterung experimenteller Infrastrukturen um neuartige Sensor eröffnen die Möglichkeit, qualitativ neuartige Erkenntnisse zu gewinnen. Um diese Informationen vollständig zu erschließen ist ein Abdecken der gesamten Verarbeitungskette von
der Datenauslese bis zu anwendungsbezogenen Auswertung erforderlich. Eine Erweiterung bestehender wissenschaftlicher Instrumente beinhaltet die strukturelle und zeitbezogene Integration der neuen Sensordaten in das Bestandssystem. Das hier vorgestellte Framework bietet durch seinen flexiblen Ansatz das Potenzial, unterschiedliche Sensortypen in unterschiedliche, leistungsfähige Plattformen zu integrieren. Zwei unterschiedliche Integrationsansätze zeigen die Flexibilität dieses Ansatzes, wobei einer auf die Steigerung der Sensitivität einer Anlage zur Sekundärionenmassenspektroskopie und der andere auf die Bereitstellung eines Prototypen zur Untersuchung von Rezyklaten ausgerichtet ist. Die sehr unterschiedlichen Hardwarevoraussetzungen und Anforderungen der Anwendung bildeten die Basis zur Entwicklung eines flexiblen Softwareframeworks. Um komplexe und leistungsfähige Applikationsbausteine bereitzustellen wurde eine Softwaretechnologie entwickelt, die modulare Pipelinestrukturen mit Sensor- und Ausgabeschnittstellen sowie einer Wissensbasis mit entsprechenden Konfigurations- und Verarbeitungsmodulen kombiniert.:1. Introduction
2. Hardware Architecture and Application Background
3. Software Concept
4. Experimental Results
5. Conclusion and OutlookNovel sensors with the ability to collect qualitatively new information offer the potential to improve experimental infrastructure and methods in the field of research technology. In order to get full access to this information, the entire range from detector readout data transfer over proper data and knowledge models up to complex application functions has to be covered. The extension of existing scientific instruments comprises the integration of diverse sensor information into existing hardware, based on the expansion of pivotal event schemes and data models. Due to its flexible approach, the proposed framework has the potential to integrate additional sensor types and offers migration capabilities to high-performance computing platforms. Two different implementation setups prove the flexibility of this approach, one extending the material analyzing capabilities of a secondary ion mass spectrometry device, the other implementing a functional prototype setup for the online analysis of recyclate. Both setups can be regarded as two complementary parts of a highly topical and ground-breaking unique scientific application field. The requirements and possibilities resulting from different hardware concepts on one hand and diverse application fields on the other hand are the basis for the development of a versatile software framework. In order to support complex and efficient application functions under heterogeneous and flexible technical conditions, a software technology is proposed that offers modular processing pipeline structures with internal and external data interfaces backed by a knowledge base with respective configuration and conclusion mechanisms.:1. Introduction
2. Hardware Architecture and Application Background
3. Software Concept
4. Experimental Results
5. Conclusion and Outloo
Магнитоэлектрический двигатель для привода рулевой колонки автотранспортного средства
Научная квалификационная работа посещена исследованию пульсаций электромагнитного момента в магнитоэлектрическом двигателе рулевой колонки автотранспортного средства. В первой главе выполнен обзор исследований на тему магнитоэлектрических машин с различной компоновкой магнитов на роторе и осуществлена постановка задачи научной квалификационной работы. Во второй главе рассмотрены вопросы имитационного моделирования магнитоэлектрической машины в конечно-элементной компьютерной среде. Выполнено планирование эксперимента, получена взаимосвязь между количеством пазов ротора, зубцами статора, коэрцитивной силы магнитов с позиции значений электромагнитного момента. В третьей главе выполнен расчет связанной модели магнитоэлектрический двигатель-инвертор напряжения-система управления.Scientific qualification work is visited to a research of pulsations of the electromagnetic torque in the magnetoelectric motor of a steering column of the vehicle. In chapter 1 the review of researches on magnetoelectric machine with various configuration of magnets on a rotor is executed and problem definition of scientific qualification work is carried out. In chapter 2 questions of a simulation modeling of the magnetoelectric machine in the terminating and element computer environment are considered. Scheduling of an experiment is executed, the interrelation between quantity of poles of a rotor, tooths of a stator, a coercive force of magnets from a position of values of the electromagnetic torque is received. In a chapter 3 calculation of the bound model the magnetoelectric motor
Расчет коэффициентов характеризующих форму наплавляемого валика при восстановлении изношенных деталей
Методика создания конечно-элементной модели и расчета крупногабаритного трансформируемого сетчатого рефлектора космического аппарата
Laserablation für Temporallappenepilepsien
Die interstitielle thermale Lasertherapie findet immer häufiger bei refraktären Epilepsieerkrankungen Anwendung. Dabei handelt es sich um eine neuartige minimal invasive Methode, mit der mittels Magnetresonanztomografie unter direkter Kontrolle von Temperatur und Ablation auch tief im Gehirn gelegene Areale behandelt werden können. Dieser Beitrag fasst den aktuellen Wissensstand zur Laserbehandlung von Temporallappenepilepsien zusammen und vergleicht diese Technik mit anderen epilepsiechirurgischen Optionen
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