Representation of Nelson Algebras by Rough Sets Determined by Quasiorders

In this paper, we show that every quasiorder $R$ induces a Nelson algebra $\mathbb{RS}$ such that the underlying rough set lattice $RS$ is algebraic. We note that $\mathbb{RS}$ is a three-valued {\L}ukasiewicz algebra if and only if $R$ is an equivalence. Our main result says that if $\mathbb{A}$ is a Nelson algebra defined on an algebraic lattice, then there exists a set $U$ and a quasiorder $R$ on $U$ such that $\mathbb{A} \cong \mathbb{RS}$.Comment: 16 page

Dynamic modulation of beta band cortico-muscular coupling induced by audio-visual rhythms

Human movements often spontaneously fall into synchrony with auditory and visual environmental rhythms. Related behavioral studies have shown that motor responses are automatically and unintentionally coupled with external rhythmic stimuli. However, the neurophysiological processes underlying such motor entrainment remain largely unknown. Here we investigated with electroencephalography (EEG) and electromyography (EMG) the modulation of neural and muscular activity induced by periodic audio and/or visual sequences. The sequences were presented at either 1 Hz or 2 Hz while participants maintained constant finger pressure on a force sensor. The results revealed that although there was no change of amplitude in participants’ EMG in response to the sequences, the synchronization between EMG and EEG recorded over motor areas in the beta (12–40 Hz) frequency band was dynamically modulated, with maximal coherence occurring about 100 ms before each stimulus. These modulations in beta EEG–EMG motor coherence were found for the 2 Hz audio-visual sequences, confirming at a neurophysiological level the enhancement of motor entrainment with multimodal rhythms that fall within preferred perceptual and movement frequency ranges. Our findings identify beta band cortico-muscular coupling as a potential underlying mechanism of motor entrainment, further elucidating the nature of the link between sensory and motor systems in humans

Sonocrystallisation of ZIF-8 in water with high excess of ligand: Effects of frequency, power and sonication time

A systematic study on the sonocrystallisation of ZIF-8 (zeolitic imidazolate framework-8) in a water-based system was investigated under different mixing speeds, ultrasound frequencies, calorimetric powers and sonication time. Regardless of the synthesis technique, pure crystals of ZIF-8 with high BET (Brunauer, Emmett and Teller) specific surface area (SSA) can be obtained in water after only 5 s. Furthermore, 5 s sonication produced even smaller crystals (~0.08 µm). The type of technique applied for producing the ZIF-8 crystals did not have any significant impact on crystallinity, purity and yield. Crystal morphology and size were affected by the use of ultrasound and mixing, obtaining nanoparticles with a more spherical shape than in silent condition (no ultrasound and mixing). However, no specific trends were observed with varying frequency, calorimetric power and mixing speed. Ultrasound and mixing may have an effect on the nucleation step, causing the fast production of nucleation centres. Furthermore, the BET SSA increased with increasing mixing speed. With ultrasound, the BET SSA is between the values obtained under silent condition and with mixing. A competition between micromixing and shockwaves has been proposed when sonication is used for ZIF-8 production. The former increases the BET SSA, while the latter could be responsible for porosity damage, causing a decrease of the surface area. © 2021 The Author(s

Postoperative bladder dysfunction and outcomes after minimally invasive extravesical ureteric reimplantation in children using a laparoscopic and a robot-assisted approach: results of a multicentre international survey

OBJECTIVES: To assess and compare postoperative bladder dysfunction rates and outcomes after laparoscopic and robot-assisted extravesical ureteric reimplantation in children and to identify risk factors associated with bladder dysfunction. PATIENTS AND METHODS: A total of 151 children underwent minimally invasive extravesical ureteric reimplantation in five international centres of paediatric urology over a 5-year period (January 2013-January 2018). The children were divided in two groups according to surgical approach: group 1 underwent laporoscopic reimplantation and included 116 children (92 girls and 24 boys with a median age of 4.5 years), while group 2 underwent robot-assisted reimplantation and included 35 children (29 girls and six boys with a median age of 7.5 years). The two groups were compared with regard to: procedure length; success rate; postoperative complication rate; and postoperative bladder dysfunction rate (acute urinary retention [AUR] and voiding dysfunction). Univariate and multivariate logistic regression analyses were performed to assess predictors of postoperative bladder dysfunction. Factors assessed included age, gender, laterality, duration of procedure, pre-existing bladder and bowel dysfunction (BBD) and pain control. RESULTS: The mean operating time was significantly longer in group 2 compared with group 1, for both unilateral (159.5 vs 109.5 min) and bilateral procedures (202 vs 132 min; P = 0.001). The success rate was significantly higher in group 2 than in group 1 (100% vs 95.6%; P = 0.001). The overall postoperative bladder dysfunction rate was 8.6% and no significant difference was found between group 1 (6.9%) and group 2 (14.3%; P = 0.17). All AUR cases were managed with short-term bladder catheterization except for two cases (1.3%) in group 1 that required short-term suprapubic catheterization. Univariate and multivariate analyses showed that bilateral pathology, pre-existing BBD and duration of procedure were predictors of postoperative bladder dysfunction (P = 0.001). CONCLUSION: Our results confirmed that short-term bladder dysfunction is a possible complication of extravesical ureteric reimplantation, with no significant difference between the laparoscopic and robot-assisted approaches. Bladder dysfunction occurred more often after bilateral repairs, but required suprapubic catheterization in only 1.3% of cases. Bilaterality, pre-existing BBD and duration of surgery were confirmed on univariate and multivariate analyses as predictors of postoperative bladder dysfunction in this series

Expression and function of aquaporins in human skin: Is aquaporin-3 just a glycerol transporter?

AbstractThe aquaporins (AQPs) are a family of transmembrane proteins forming water channels. In mammals, water transport through AQPs is important in kidney and other tissues involved in water transport. Some AQPs (aquaglyceroporins) also exhibit glycerol and urea permeability. Skin is the limiting tissue of the body and within skin, the stratum corneum (SC) of the epidermis is the limiting barrier to water loss by evaporation. The aquaglyceroporin AQP3 is abundantly expressed in keratinocytes of mammalian skin epidermis. Mice lacking AQP3 have dry skin and reduced SC hydration. Interestingly, however, results suggested that impaired glycerol, rather than water transport was responsible for this phenotype. In the present work, we examined the overall expression of AQPs in cells from human skin and we reviewed data on the functional role of AQPs in skin, particularly in the epidermis. By RT-PCR on primary cell cultures, we found that up to 6 different AQPs (AQP1, 3, 5, 7, 9 and 10) may be selectively expressed in various cells from human skin. AQP1, 5 are strictly water channels. But in keratinocytes, the major cell type of the epidermis, only the aquaglyceroporins AQP3, 10 were found. To understand the role of aquaglyceroporins in skin, we examined the relevance to human skin of the conclusion, from studies on mice, that skin AQP3 is only important for glycerol transport. In particular, we find a correlation between the absence of AQP3 and intercellular edema in the epidermis in two different experimental models: eczema and hyperplastic epidermis. In conclusion, we suggest that in addition to glycerol, AQP3 may be important for water transport and hydration in human skin epidermis

Changes in aroma and sensory profile of food ingredients smoked in the presence of a zeolite filter

During smoking, formation of desirable smoky compounds and carcinogenic polycyclic aromatic hydrocarbons (PAH) are inextricably linked. We have previously developed a zeolite filter technology (PureSmoke Technology or PST) that reduces the PAH content of a smoke stream, particularly reducing the concentration of benzo[a]pyrene, a known carcinogen, by up to 93%. The aim of this work was to determine whether there were changes in the volatile and sensory profiles of ingredients smoked using PST compared to the traditional smoking process (Trad). Smoked tomato flakes (either PST or Trad) were added to either low-fat or full-fat cream cheese for sensory profiling and consumer preference tests, and volatile analysis was carried out using solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS). The sensory analysis showed a significant decrease (p < 0.01) in bitterness when the PST was employed and a significant decrease in overall smoky aroma and flavor (p < 0.001), which resulted in an increase in the perception of cheesy aroma and flavor. This was consistent with a decrease in many of the smoky aroma compounds, particularly the guaiacols. However, consumer preference tests showed that there was no adverse effect on the flavor of the products, and there was even a tendency for the PST product to be preferred to the Trad product (p = 0.096). The smoke compounds were quantitated and compared in smoked tomato paste. Odor activity values (OAVs) calculated from the literature thresholds suggested that guaiacol and 4-alk(en)yl-substituted guaiacols are likely to be among the most highly odor-active compounds in these smoked ingredients

Xenon detection in human blood: Analytical validation by accuracy profile and identification of critical storage parameters.

Xenon is a rare, mostly inert, noble gas that has applications in a wide range of fields, including medicine. Xenon acts on the human body as a useful organ-protective and anesthetic agent and has also been previously studied for potential applications in fields such as optics, aerospace and medical imaging. Recently, it was discovered that xenon can boost erythropoietin production, and it has been used as a performance-enhancing agent in international sports competitions such as the Sochi Olympic Games. Therefore, screening methods to detect the misuse of xenon by analysis of biological samples and to monitor anesthesia kinetics and efficiency are being investigated. The aim of this study was to develop and validate an analytical method to detect xenon in blood samples using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Preliminary studies were conducted to determine the best parameters for chromatography and mass spectrometry for xenon. The analysis was performed using the multiple reaction monitoring (MRM) mode using the transitions m/z 129 → 129, 131 → 131 for xenon and 84 → 84, 86 → 86 for krypton, which was chosen as the internal standard. The LOD of GC-MS/MS was found to be 52 pmol on-column. Calibration lines and controls were made to obtain an accuracy profile at a range of 2.08-104 nmol with a β-expectation tolerance interval set at 80% and the acceptability limit set at ±30%. From the accuracy profile, the LOQ of 15 nmol on-column for the range of 2.08-104 nmol was obtained. The method was validated according to the guidelines of the French Society of Pharmaceutical Sciences and Techniques. The detection method was finally validated using blood from test persons subjected to a 15% or 30% xenon mixture with pure oxygen and air for 45 min. Even though the probes were already used for other projects, it was still possible to detect xenon

Neural multimodal integration underlying synchronization with a co-performer in music: influences of motor expertise and visual information

Sensorimotor synchronization is a general skill that musicians have developed to the highest levels of performance, including synchronization in timing and articulation. This study investigated neurocognitive processes that enable such high levels of performance, specifically testing the relevance of 1) motor resonance and sharing high levels of motor expertise with the co-performer, and 2) the role of visual information in addition to auditory information. Musicians with varying levels of piano expertise (including non-pianists) performed on a single piano key with their right hand along with recordings of a pianist who performed simple melodies with the left hand, synchronizing timing and articulation. The prerecorded performances were presented as audio-only, audio-video, or audio-animation stimuli. Double pulse Transcranial Magnetic Stimulation (dTMS) was applied to test the contribution of the right dorsal premotor cortex (dPMC), an area implicated in motor resonance with observed (left-hand) actions, and the contribution of the right intraparietal sulcus (IPS), an area known for multisensory binding. Results showed effects of dTMS in the conditions that included visual information. IPS stimulation improved synchronization ability, although this effect was found to reverse for the video condition with higher levels of relevant motor expertise. dPMC stimulation improved or worsened synchronization ability. Level of relevant motor expertise was found to influence this direction in the video condition. These results indicate that high levels of relevant motor expertise are required to beneficially employ visual and motor information of a co-performer for sensorimotor synchronization, which may qualify the effects of dPMC and IPS involvement

Ballistic Josephson junctions in edge-contacted graphene

Hybrid graphene-superconductor devices have attracted much attention since the early days of graphene research. So far, these studies have been limited to the case of diffusive transport through graphene with poorly defined and modest quality graphene-superconductor interfaces, usually combined with small critical magnetic fields of the superconducting electrodes. Here we report graphene based Josephson junctions with one-dimensional edge contacts of Molybdenum Rhenium. The contacts exhibit a well defined, transparent interface to the graphene, have a critical magnetic field of 8 Tesla at 4 Kelvin and the graphene has a high quality due to its encapsulation in hexagonal boron nitride. This allows us to study and exploit graphene Josephson junctions in a new regime, characterized by ballistic transport. We find that the critical current oscillates with the carrier density due to phase coherent interference of the electrons and holes that carry the supercurrent caused by the formation of a Fabry-P\'{e}rot cavity. Furthermore, relatively large supercurrents are observed over unprecedented long distances of up to 1.5 $\mu$m. Finally, in the quantum Hall regime we observe broken symmetry states while the contacts remain superconducting. These achievements open up new avenues to exploit the Dirac nature of graphene in interaction with the superconducting state.Comment: Updated version after peer review. Includes supplementary material and ancillary file with source code for tight binding simulation

A tiered approach to the use of alternatives to animal testing for the safety assessment of cosmetics: Eye irritation

AbstractThe need for alternative approaches to replace the in vivo rabbit Draize eye test for evaluation of eye irritation of cosmetic ingredients has been recognised by the cosmetics industry for many years. Extensive research has lead to the development of several assays, some of which have undergone formal validation. Even though, to date, no single in vitro assay has been validated as a full replacement for the rabbit Draize eye test, organotypic assays are accepted for specific and limited regulatory purposes. Although not formally validated, several other in vitro models have been used for over a decade by the cosmetics industry as valuable tools in a weight of evidence approach for the safety assessment of ingredients and finished products. In light of the deadlines established in the EU Cosmetics Directive for cessation of animal testing for cosmetic ingredients, a COLIPA scientific meeting was held in Brussels on 30th January, 2008 to review the use of alternative approaches and to set up a decision-tree approach for their integration into tiered testing strategies for hazard and safety assessment of cosmetic ingredients and their use in products. Furthermore, recommendations are given on how remaining data gaps and research needs can be addressed