Model of a Context-Aware Middleware for Mobile Workers

With the development of Internet of things and Web of things, computing becomes more pervasive, invisible and present everywhere. In fact, in our environment, we are surrounded by multiple devices that deliver (web) services which meet the needs of the users. However, the mobility of these devices as the users has important repercussions that challenge software design of these applications because the variability of the environment cannot be anticipated at the design time. Thus, it will be interesting to dynamically discover the environment and adapt the application during its execution to the new contextual conditions. We therefore, propose a model of a context-aware middleware that can address this issue through a monitoring service which is capable of reasoning and observation channels capable of calculating the context during the runtime. The monitoring service evaluates the pre-defined X-Query predicates in the context manager and uses Prolog to deduce the services needed to respond back. An independent observation channel for each different predicate is then dynamically generated by the monitoring service depending on the current state of the environment. Each channel sends its result directly to the context manager which consequently calculates the context based on all the predicates’ results while preserving the reactivity of the self-adaptive system.

Overcoming the limitations of 3D sensors with wide field of view metasurface-enhanced scanning lidar

Lidar, a technology at the heart of autonomous driving and robotic mobility, performs 3D imaging ofa complex scene by measuring the time of flight of returning light pulses. Many technological challenges,including enhancement of the observation field of view (FoV), acceleration of the imaging frame rate,improvement of the ambiguity range, reduction of fabrication cost, and component size, must besimultaneously addressed so that lidar technology reaches the performance needed to strongly impact theglobal market. We propose an innovative solution to address the problem of wide FoV and extendedunambiguous range using an acousto-optic modulator that rapidly scans a large-area metasurface deflector.We further exploit a multiplexing illumination technique traditionally deployed in the context of telecommu-nication theory to extend the ambiguity range and to drastically improve the signal-to-noise ratio of themeasured signal. Compacting our metasurface-scanning lidar system to chip-scale dimension would opennew and exciting perspectives, eventually relevant to the autonomous vehicles and robotic industries.

Creation of periodical domain structure by local polarization reversal in planar waveguide produced by soft proton exchange in LiNbO_(3)

The paper presents the results of an experimental study of the local polarization reversal and creation of domains by a biased tip of scanning probe microscope(SPM)in lithium niobate single crystals of congruent composition with a surface layer modified by soft proton exchange(SPE).The depth dependence of Ht ions concentration in the SPE-modified layer measured by confocal Raman microscopy demonstrates a sufficient composition gradient.The creation of isolated domains and stripe domain structures has been done by two switching modes:(1)point switching by field application in separated points and(2)line scanning switching by motion of the biased tip being in contact with the sample surface.For point switching for pulse durations less than 10 s,the logarithmic dependence of the domain diameter on the pulse duration was observed.The change of the dependence to a linear one for pulse duration above 10 s has been attributed to the transition from the stochastic step generation at the domain wall to the deterministic one at the domain vertexes.The periodical structure of stripe domains was created in SPE CLN planar waveguides by scanning at elevated temperature.The revealed switching regime suppresses electrostatic interaction of neighboring domains and leads to a significant improvement of the domain structure regularity.The creation of the stable periodical domain structure with submicron periods in SPE CLN planar waveguides was demonstrated.

Chitinase 6 is required for procuticle thickening and organ shape in Drosophila wing

The polysaccharide chitin is a major scaffolding molecule in the insect cuticle.In order to be functional,both chitin amounts and chitin organization have been shown to be important parameters.Despite great advances in the past decade,the molecular mechanisms of chitin synthesis and organization are not fully understood.Here,we have characterized the function of the Chitinase 6(Cht6)in the formation of the wing,which is a simple flat cuticle organ,in the fruit fly Drosophila melanogaster.Reduction of Cht6 function by RNA interference during wing development does not affect chitin organization,but entails a thinner cuticle suggesting reduced chitin amounts.This phenotype is opposed to the one reported recently to be caused by reduction of Cht10 expression.Probably as a consequence,cuticle permeability to xenobiotics is enhanced in Cht6-less wings.We also observed massive deformation of these wings.In addition,the shape of the abdomen is markedly changed upon abdominal suppression of Cht6.Finally,we found that suppression of Cht6 transcript levels influences the expression of genes coding for enzymes of the chitin biosynthesis pathway.This finding indicates that wing epidermal cells respond to activity changes of Cht6 probably trying to adjust chitin amounts.Together,in a working model,we propose that Cht6-introduced modifications of chitin are needed for chitin synthesis to proceed correctly.Cuticle thickness,according to our hypothesis,is in turn required for correct organ or body part shape.The molecular mechanisms of this processes shall be characterized in the future.

Hepatocyte apoptosis fragment product cytokeratin-18 M30 level and non-alcoholic steatohepatitis risk diagnosis:an international registry study

Background:Liver biopsy for the diagnosis of non-alcoholic steatohepatitis(NASH)is limited by its inherent invasiveness and possible sampling errors.Some studies have shown that cytokeratin-18(CK-18)concentrations may be useful in diagnosing NASH,but results across studies have been inconsistent.We aimed to identify the utility of CK-18 M30 concentrations as an alternative to liver biopsy for non-invasive identification of NASH.Methods:Individual data were collected from 14 registry centers on patients with biopsy-proven non-alcoholic fatty liver disease(NAFLD),and in all patients,circulating CK-18 M30 levels were measured.Individuals with a NAFLD activity score(NAS)≥5 with a score of≥1 for each of steatosis,ballooning,and lobular inflammation were diagnosed as having definite NASH;individuals with a NAS≤2 and no fibrosis were diagnosed as having non-alcoholic fatty liver(NAFL).Results:A total of 2571 participants were screened,and 1008(153 with NAFL and 855 with NASH)were finally enrolled.Median CK-18 M30 levels were higher in patients with NASH than in those with NAFL(mean difference 177 U/L;standardized mean difference[SMD]:0.87[0.69–1.04]).There was an interaction between CK-18 M30 levels and serum alanine aminotransferase,body mass index(BMI),and hypertension(P<0.001,P=0.026 and P=0.049,respectively).CK-18 M30 levels were positively associated with histological NAS in most centers.The area under the receiver operating characteristics(AUROC)for NASH was 0.750(95%confidence intervals:0.714–0.787),and CK-18 M30 at Youden’s index maximum was 275.7 U/L.Both sensitivity(55%[52%–59%])and positive predictive value(59%)were not ideal.Conclusion:This large multicenter registry study shows that CK-18 M30 measurement in isolation is of limited value for non-invasively diagnosing NASH.

Observation of supersymmetric pseudo-Landau levels in strained microwave graphene

Using an array of coupled microwave resonators arranged in a deformed honeycomb lattice,we experimentally observe the formation of pseudo-Landau levels in the whole crossover from vanishing to large pseudomagnetic field strengths.This result is achieved by utilising an adaptable setup in a geometry that is compatible with the pseudo-Landau levels at all field strengths.The adopted approach enables us to observe the fully formed flat-band pseudo-Landau levels spectrally as sharp peaks in the photonic density of states and image the associated wavefunctions spatially,where we provide clear evidence for a characteristic nodal structure reflecting the previously elusive supersymmetry in the underlying low-energy theory.In particular,we resolve the full sublattice polarisation of the anomalous 0th pseudo-Landau level,which reveals a deep connection to zigzag edge states in the unstrained case.

Formation of Nanotubular Structures with Petal Effect by Soft-Template Electropolymerization of Benzotrithiophene with Hydrophilic Carboxyl Group

The bioinspiration is one of the best ways to make a breakthrough in a field,and particularly in the wetting properties.Bioinspired by natural species,such as rose petals and gecko foot,and previous researches,nanotubular structures are prepared here by soft-template electropolymerization in organic solvent and using an original benzotrithiophene with a hydrophilic carboxyl group,as the monomer.The best results are obtained by cyclic voltammetry because of a much higher amount of gas bubbles released with this deposition method.Both nanoparticles and nanotubes are observed while the water content has an influence on the number of nanotubes.Even if the monomer has hydrophilic carboxyl group,the best films have both high hydrophobicity(apparent water contact angle up to 130.7°)and strong water adhesion(petal effect).These surfaces could be used in future in applications such as water harvesting systems.

Effect of Electrolyte Nature on Micellar Soft-Template Electropolymerization in Organic Solvent to Form Nanoporous Polymer Films with a Bioinspired Strategy

Here,using a bioinspired approach,the soft-template electropolymerization of naphtho[2,3-b]thieno[3,4-e][1,4]dioxine(NaphDOT)was conducted in dichloromethane with different water content,and using different supporting electrolytes.The role of the electrolytes in the formation of reverse micelles that constitutes the soft template is investigated.The reverse micelles stabilized by the electrolyte and the monomer were observed by TEM and related to the various porous nanostructures of the obtained polymer films.We show that the nature of the electrolyte is not only fundamental for the formation of reverse micelles and thus porous nanostructures,but also plays a huge role in the good deposition of the oligomers upon the soft template.Surfaces with nanostructures such as nanotubes,nanorings or nanomembranes were realized.

Harmonizing the COVID-19 sample biobanks: Barriers and opportunities for standards, best practices and networks

The coronavirus disease 2019(COVID-19)pandemic has highlighted the practice of infectious diseases biobanking,as well as existing challenges and opportunities.Thus,the future of infectious diseases biobanking in the post-pandemic era,shall not be an“entry-level version”of its counterpart in non-communicable diseases and large population cohorts,but incorporate the lessons learned.Biobanks constitute a critical research infrastructure supported by harmonized practices through the implementation of international standards,and perceived within the broader scope of healthcare's intersection with research.This perspective paper considers the barriers in biobanking and standardization of practices,as well as the emerging opportunities in the field.

Displacement Talbot lithography for nanoengineering of III-nitride materials

Nano-engineering III-nitride semiconductors offers a route to further control the optoelectronic properties,enabling novel functionalities and applications.Although a variety of lithography techniques are currently employed to nanoengineer these materials,the scalability and cost of the fabrication process can be an obstacle for large-scale manufacturing.In this paper,we report on the use of a fast,robust and flexible emerging patterning technique called Displacement Talbot lithography(DTL),to successfully nano-engineer III-nitride materials.DTL,along with its novel and unique combination with a lateral planar displacement(D^(2)TL),allow the fabrication of a variety of periodic nanopatterns with a broad range of filling factors such as nanoholes,nanodots,nanorings and nanolines;all these features being achievable from one single mask.To illustrate the enormous possibilities opened by DTL/D2TL,dielectric and metal masks with a number of nanopatterns have been generated,allowing for the selective area growth of InGaN/GaN core-shell nanorods,the top-down plasma etching of III-nitride nanostructures,the top-down sublimation of GaN nanostructures,the hybrid top-down/bottom-up growth of AlN nanorods and GaN nanotubes,and the fabrication of nanopatterned sapphire substrates for AlN growth.Compared with their planar counterparts,these 3D nanostructures enable the reduction or filtering of structural defects and/or the enhancement of the light extraction,therefore improving the efficiency of the final device.These results,achieved on a wafer scale via DTL and upscalable to larger surfaces,have the potential to unlock the manufacturing of nano-engineered III-nitride materials.

Perovskite polariton parametric oscillator

Optical parametric oscillators(OPOs)have been widely applied in spectroscopy,squeezed light,and correlated photons,as well as quantum information.Conventional OPOs usually suffer from a high power threshold limited by weak high-order nonlinearity in traditional pure photonic systems.Alternatively,polaritonic systems based on hybridized exciton–photon quasi-particles exhibit enhanced optical nonlinearity by dressing photons with excitons,ensuring highly nonlinear operations with low power consumption.We report an on-chip perovskite polariton parametric oscillator with a low threshold.Under the resonant excitation at a range of angles,the signal at the ground state is obtained,emerging from the polariton-polariton interactions at room temperature.Our results advocate a practical way toward integrated nonlinear polaritonic devices with low thresholds.