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In this article, we present an approach to the ABZ 2020 case study that differs from those usually presented at ABZ: Rather than using a (correct-by-construction) approach following a formal method, we use C for a low-level implementation instead. We strictly adhere to test-driven development for validation, and only afterwards apply model checking using CBMC for verification. While the approach has several benefits compared to the more rigorous approaches, it also provides less mathematical clarity and overall less thorough verification. In consequence, our realization of the ABZ case study serves as a baseline reference for comparison, allowing to assess the benefit provided by the various formal modeling languages, methods and tools. [ABSTRACT FROM AUTHOR]

This pilot study investigated whether sonic-powered application of a bulk-fill resin-based composite (RBC) in Class-II or endodontic access cavities reduces void formation. The crowns and roots of 60 bovine teeth with Class-II cavities (C) and endodontic access cavities (E) respectively, were assigned to ten groups (C1–C5, E1–E5). Cavities were filled with RBC (SDR flow + , one increment) using different application techniques: no adaptation (C1 + E1), spreading of RBC on the cavity surfaces with a dental explorer tip (C2 + E2), low (C3 + E3) or high frequency (C4 + E4) direct activation by inserting a sonic-powered tip into RBC and high frequency indirect activation with an ultrasonic insertion tip (C5 + E5). The restorations were light-cured and investigated for voids using microtomography. The number of voids and percentage of voids related to the volume were statistically analysed (α < 0.05). While most voids in Class-II restorations were observed in C4 (p ≤ 0.0031), no significant differences were found between the other groups (p > 0.05). The percentage of voids showed no differences in E1-E5 (p > 0.05). C4 showed a significantly higher percentage of voids compared to C2 (p < 0.001). There is no benefit in applying sonic vibration when filling Class-II or endodontic access cavities. [ABSTRACT FROM AUTHOR]

The geometrical properties of toothbrushes play a role in developing abrasive tooth wear and non-carious cervical lesions. This study investigated the interplay between the toothbrush tuft arrangement (crossed vs. parallel) and bristle stiffness (soft vs. medium) on the abrasive dentin wear using three slurries with different levels of abrasivity (RDA: 67, 121 and 174). Twelve groups of bovine dentin samples (n = 20) were brushed with a combination of the aforementioned variables. Abrasive dentin wear was recorded with a profilometer and the resulting abrasive wear of each group was calculated and compared with each other using two-way ANOVA and pairwise tests. Toothbrushes with parallel tuft arrangement caused statistically significantly higher dentin wear compared to crossed tuft arrangement, regardless of the abrasivity level of the used slurry and the bristle stiffness. Soft crossed tuft toothbrushes caused statistically significantly higher abrasive dentin wear than medium crossed tuft toothbrushes, while soft and medium parallel tuft toothbrushes caused the same amounts of dentin wear, regardless of the RDA value of the used slurry. These results could be helpful for dentists and dental hygienists when advising patients. Crossed tuft toothbrushes could be a less-abrasive choice in comparison to parallel tuft toothbrushes. [ABSTRACT FROM AUTHOR]

The common formal methods workflow consists of formalising a model followed by applying model checking and proof techniques. Once an appropriate level of certainty is reached, code generators are used in order to gain executable code. In this paper, we propose a different approach: instead of generating code from formal models, it is also possible to embed a model checker or animator into applications in order to use the formal models themselves at runtime. We present a Java API to the ProB animator and model checker. We describe several case studies that use this API as enabling technology to interact with a formal specification at runtime. [ABSTRACT FROM AUTHOR]

In this article, we present a concrete realisation of the ETCS hybrid level 3 concept, whose practical viability was evaluated in a field demonstration in 2017. Hybrid level 3 introduces virtual subsections as sub-divisions of classical track sections with trackside train detection. Our approach introduces an add-on for the radio block centre (RBC) of Thales, called virtual block function (VBF), which computes the occupation states of the virtual subsections using the train position reports, train integrity information, and the track occupation states. From the perspective of the RBC, the VBF behaves as an interlocking that transmits all signal aspects for virtual signals introduced for each virtual subsection to the RBC. We report on the development of the VBF, implemented as a formal B model executed at runtime using ProB and successfully used in a field demonstration to control real trains. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate margin integrity of Class V composite restorations in demineralized and sound enamel after bonding with different etch-and-rinse and self-etch adhesive systems. Out of a total of 60 specimens from bovine incisors, 30 specimens were demineralized (21 days, acid buffer, pH 4.95) to create artificial enamel lesions. Circular Class V cavities were prepared in all 60 specimens and treated with either an unfilled etch-and-rinse adhesive (Syntac Classic; Ivoclar Vivadent), a filled etch-and-rinse adhesive (Optibond FL; Kerr), or a self-etch adhesive (iBond Self Etch; Heraeus) (n = 10 per group). The cavities were restored with a nanofilled resin composite and thermocycled (5000×, 5–55 °C). Scanning electron microscopy was used to evaluate margin integrity of the composite restorations, and the percentage of continuous margin was statistically analyzed (α = 0.05). Demineralized enamel led to a significantly lower margin integrity when the self-etch adhesive iBond Self Etch was applied, but did not affect margin integrity when the etch-and-rinse adhesives Optibond FL (filled) or Syntac Classic (unfilled) were used. No significant differences in margin integrity in sound and demineralized enamel were observed between the different adhesives. Demineralized enamel reduces margin integrity of composite restorations when bonded with a self-etch adhesive, but does not affect margin integrity when an etch-and-rinse approach is used. [ABSTRACT FROM AUTHOR]

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Background: The benefits of patient-reported symptom assessment combined with integrated palliative care are well documented. This study assessed the symptom burden of palliative and curative-intent radiation oncology patients.Patients and Methods: Prior to first consultation and at the end of RT, all adult cancer patients planned to receive fractionated percutaneous radiotherapy (RT) were asked to answer the Edmonton Symptom Assessment Scale (ESAS; nine symptoms from 0 = no symptoms to 10 = worst possible symptoms). Mean values were used for curative vs. palliative and pre-post comparisons, and the clinical relevance was evaluated (symptom values ≥ 4).Results: Of 163 participating patients, 151 patients (90.9%) completed both surveys (116 curative and 35 palliative patients). Before beginning RT, 88.6% of palliative and 72.3% of curative patients showed at least one clinically relevant symptom. Curative patients most frequently named decreased general wellbeing (38.6%), followed by tiredness (35.0%), anxiety (32.4%), depression (30.0%), pain (26.3%), lack of appetite (23.5%), dyspnea (17.8%), drowsiness (8.0%) and nausea (6.1%). Palliative patients most frequently named decreased general wellbeing (62.8%), followed by pain (62.8%), tiredness (60.0%), lack of appetite (40.0%), anxiety (38.0%), depression (33.3%), dyspnea (28.5%), drowsiness (25.7%) and nausea (14.2%). At the end of RT, the proportion of curative and palliative patients with a clinically relevant symptom had increased significantly to 79.8 and 91.4%, respectively; whereas the proportion of patients reporting clinically relevant pain had decreased significantly (42.8 vs. 62.8%, respectively). Palliative patients had significantly increased tiredness. Curative patients reported significant increases in pain, tiredness, nausea, drowsiness, lack of appetite and restrictions in general wellbeing.Conclusion: Assessment of patient-reported symptoms was successfully realized in radiation oncology routine. Overall, both groups showed a high symptom burden. The results prove the need of systematic symptom assessment and programs for early integrated supportive and palliative care in radiation oncology. [ABSTRACT FROM AUTHOR]