Successful Attempt Research Articles

Simultaneous Determination of Tannic Acid and Eugenol in Newly Formulated Churna of Tulsi and Parijat

Herbal formulations are widely used to treat a variety of diseases with the use of natural ingredients and have the additional advantage of negligible side effects. Looking towards the wide applicability of herbal formulations, a novel herbal formulation containing Tulsi and Parijat has been formulated and evaluated for different standardisation parameters. Tulsi and Parijat both possess multiple natural effects like antibacterial, antiviral and antipyretic properties along with wide applicability to treat different respiratory problems. Therefore, the combination of these two naturally available herbs can provide good immunomodulatory action for humans. Apart from the various phytoconstituents present in these two herbs, eugenol and tannic acid are found to have versatile effects. They are widely used to treat various common health issues like tonsillitis and various respiratory complaints like cough, cold and sour throat. A successful attempt has been made to develop the HPTLC method for the simultaneous determination of Tannic acid and Eugenol in pure and newly formulated churna containing Tulsi and Parijat as chief herbs. Tannic acid and eugenol mixtures get resolved by toluene:ethyl acetate:formic acid (5:3:2) with Rf of 0.849 ± 0.003 and 0.534 ± 0.009 respectively for tannic acid and eugenol. Linearity is observed within the range of 250–1500 ng/band for both eugenol and tannic acid. According to ICH Q2 R1 advice for analytical method validation, this designed technique has been effectively validated.

Reconstruction of the Native Biosynthetic System of Carotenoids in E. coli─Biosynthesis of a Series of Carotenoids Specific to Paprika Fruit

Capsanthin, capsorubin, cucurbitaxanthin A, and capsanthin 3,6-epoxide, a series of carotenoids specific to the red fruit of paprika (Capsicum annuum), were produced in pathway-engineered Escherichia coli cells. These cells functionally expressed multiple genes for eight carotenogenic enzymes, two of which, paprika capsanthin/capsorubin synthase (CaCCS) and zeaxanthin epoxidase (CaZEP), were designed to be located adjacently. The biosynthesis of these carotenoids, except for capsanthin, was the first successful attempt in E. coli. In a previous study, the levels of capsanthin synthesized were low despite the high expression of the CaCCS gene, which may have been due to the dual activity of CaCCS as a lycopene β-cyclase and CCS. An enhanced interaction between CaCCS and CaZEP that supplies antheraxanthin and violaxanthin, substrates for CaCCS, was considered to be crucial for an efficient reaction. To achieve this, we adapted S·tag and S-protein binding. The S·tag Thrombin Purification Kit (Novagen) is merchandized for in vitro affinity purification, and S·tag-fused proteins in the E. coli lysate are specifically trapped by S-proteins fixed on the agarose carrier. Furthermore, S-proteins have been reported to oligomerize via C-terminal swapping. In the present study, CaCCS and CaZEP were individually fused to the S·tag and designed to interact on oligomerized S-protein scaffolds in E. coli, which led to the biosynthesis of not only capsanthin and capsorubin but also cucurbitaxanthin A and capsanthin 3,6-epoxide. The latter reaction by CaCCS was assigned for the first time. This approach reinforces the scaffold's importance for multienzyme pathways when native biosynthetic systems are reconstructed in microorganisms.

The relationship between gut microbiota and schizophrenia: Recent research and treatment application

Schizophrenia (SZC) is a common, chronic, and severe mental illness. Recent years have witnessed increased study into the link between gut microbiome and psychotic disorders, particularly schizophrenia. Focusing on inflammatory, tryptophan compounds, and BDNF concentrations, we examine the data that currently exists linking intestinal microbiota to schizophrenia and explain how the presumptive dysregulation could fit into accepted theories of the disease's pathophysiology. We looked at recent research and assessed the therapeutic possibility of modifying the intestinal microbiota with prebiotics as adjuvant therapy for schizophrenia. Overall, although the available information on microbiome changes in schizophrenia is extremely erratic and inadequate to draw any firm conclusions. There were successful attempts that decreased the risk of SCZ by interfering with the intestinal microbiota. The gut microbiota is a possible approach to the treatment of schizophrenia.

Alkali-earth metal ion inducing multiphase transition of lanthanum-free Pb(Zr0.5Sn0.5)O3 ceramics improves the energy storage properties

Constructing the stepwise phase transition can delay the polarization process of antiferroelectric ceramics, possessing certain significance for improving the energy storage density. However, the common multiphase transitions are obtained in the rare-earth ions doped PbZrO3-based systems. In the present work, the multiphase transition can also be induced in the lanthanum-free Pb(Zr0.5Sn0.5)O3 matrix with mere doping of the alkali-earth metal ion Sr. The introduction of Sr endows the matrix with a higher lattice distortion and the reduced phase-transition temperature. Moreover, related to the induced stepwise electric field-induced phase transition, the energy storage properties are remarkably enhanced to 10.5 J/cm3 and 83.2% when the substitution content of Sr is 3 mol. %. Sr modification can adjust the phase structure by regulating the phase stability of the matrix and suppress the leakage current originating from the structural changes. This work provides a successful attempt that the phase structure and energy storage performance of antiferroelectric ceramics can also be effectively controlled through cheaper and simpler element modification. The optimized energy storage performance provides a new material selection for pulsed power devices.

New Self-Healing Metallosupramolecular Copolymers with a Complex of Cobalt Acrylate and 4′-Phenyl-2,2′:6′,2″-terpyridine

Currently, the chemistry of self-healing polymers is aimed not only at obtaining materials with high self-healing efficiency, but also at improving their mechanical performance. This paper reports on a successful attempt to obtain self-healing copolymers films of acrylic acid, acrylamide and a new metal-containing complex of cobalt acrylate with a 4'-phenyl-2,2':6',2″-terpyridine ligand. Samples of the formed copolymer films were characterized by ATR/FT-IR and UV-vis spectroscopy, elemental analysis, DSC and TGA, SAXS, WAXS and XRD studies. The incorporation of the metal-containing complex directly into the polymer chain results in an excellent tensile strength (122 MPa) and modulus of elasticity (4.3 GPa) of the obtained films. The resulting copolymers demonstrated self-healing properties both at acidic pH (assisted by HCl healing) with effective preservation of mechanical properties, and autonomously in a humid atmosphere at room temperature without the use of initiators. At the same time, with a decrease in the content of acrylamide, a decrease in the reducing properties was observed, possibly due to an insufficient amount of amide groups to form hydrogen bonds through the interface with terminal carboxyl groups, as well as a decrease in the stability of complexes in samples with a high content of acrylic acid.

Image-based modeling of vascular organization to evaluate anti-angiogenic therapy

In tumor therapy anti-angiogenic approaches have the potential to increase the efficacy of a wide variety of subsequently or co-administered agents, possibly by improving or normalizing the defective tumor vasculature. Successful implementation of the concept of vascular normalization under anti-angiogenic therapy, however, mandates a detailed understanding of key characteristics and a respective scoring metric that defines an improved vasculature and thus a successful attempt. Here, we show that beyond commonly used parameters such as vessel patency and maturation, anti-angiogenic approaches largely benefit if the complex vascular network with its vessel interconnections is both qualitatively and quantitatively assessed. To gain such deeper insight the organization of vascular networks, we introduce a multi-parametric evaluation of high-resolution angiographic images based on light-sheet fluorescence microscopy images of tumors. We first could pinpoint key correlations between vessel length, straightness and diameter to describe the regular, functional and organized structure observed under physiological conditions. We found that vascular networks from experimental tumors diverted from those in healthy organs, demonstrating the dysfunctionality of the tumor vasculature not only on the level of the individual vessel but also in terms of inadequate organization into larger structures. These parameters proofed effective in scoring the degree of disorganization in different tumor entities, and more importantly in grading a potential reversal under treatment with therapeutic agents. The presented vascular network analysis will support vascular normalization assessment and future optimization of anti-angiogenic therapy.

Comparison of Efficacy of Laryngeal Mask Versus I-Gel Airway Devices

Background: Adequate ventilation is the primary goal of general anesthesia. A variety of supra-glottic airway devices were introduced to simplify airway management and minimize complications.Objective: To compare the Laryngeal mask airway versus I-Gel in terms of insertion time, number of successful insertion attempts, and changes in hemodynamic parameters in patients getting general anesthesia.Material and Methods: This comparative study was performed at the Anesthesia department, Pir Abdul Qadir Shah Institute of Medical Sciences, Gambat from 1st July 2020 to 31st December 2020. Patients achieving the inclusion criteria were divided into two groups. In Group-A, the I-Gel device was used for airway maintenance; while in Group-B, the Laryngeal Mask Airway(LMA) was used. The mean insertion time, insertion attempts, and hemodynamic parameters were recorded and compared in both groups.Results: Total number of participants studied was 140; with 70 participants in each group. The mean age was 33.74+6.75 years in Group-A and 33.16+7.24 years in Group-B. Gender distribution showed 62.86 % (n=44) male in Group-A and 64.29% (n=45) in Group-B. A comparison of LMA versus I-Gel showed a mean insertion time of 22.81+3.09 seconds in Group-A and 31.53+2.46 seconds in Group-B (p<0.0001). The number of successful insertion attempts and the changes in the hemodynamic parameters was comparable in both groups (p>0.05).Conclusion: This study concluded that the I-Gel device has a significantly low insertion time compared to LMA in elective settings. So, its use can be handy in emergency settings.Keywords: I-Gel, LMA, General anesthesia, insertion time.

Development and evaluation of an anatomically designed and 3D printed device to enhance orotracheal intubation success in rabbits by inexperienced veterinarians

ObjectiveTo assess whether the use of a three-dimensional (3D) printed device enhances the success rate of orotracheal intubation in rabbits. Study designProspective, crossover randomized controlled trial. AnimalsA total of six mixed-breed rabbits. MethodsA device to guide the endotracheal tube was designed based on computed tomography images and then manufactured using 3D printing. Rabbits were randomly assigned for intubation by two inexperienced veterinarians using the blind (BLI), borescope- (BOR) or device- (DEV) guided techniques. Success rate, number of attempts, time to success, injury scores and propofol dose were recorded and compared. Significance was considered when p < 0.05. ResultsSuccess rate was higher in DEV (58.3%) than in BLI (8.3%) (p < 0.023), but not different from that in BOR (41.6%). Total time until successful intubation was lower in DEV (45 ± 23 seconds) and BOR (85 ± 62 seconds) than in BLI (290 seconds; p < 0.006). Time for the successful attempt was lower for DEV (35 ± 10 seconds) and BOR (74 ± 43 seconds) than in BLI (290 seconds; p < 0.0001). The propofol dose required was lower for DEV (2.3 ± 1.2 mg kg–1) than for BLI (3.4 ± 1.6 mg kg–1) (p < 0.031), but not different from BOR (2.4 ± 0.9 mg kg–1). Number of attempts and oxygen desaturation events were not different among techniques (p < 0.051 and p < 0.326, respectively). Injury scores [median (range)] before and after attempts were different in BLI [0 versus 1 (0–3), p < 0.005] and BOR [0 (0–1) versus 1 (0–3), p < 0.002] but not in DEV [0 (0–2) versus 0 (0–3), p < 0.109]. Conclusions and clinical relevanceThe device facilitated orotracheal intubation with a time similar to the borescope-guided technique but faster than the traditional blind technique.

EEG-based source localization with enhanced virtual aperture using second order statistics

For the past few decades source localization, based on EEG modality, has been a very active area of research. EEG signal provides temporal resolution in millisecond range that can capture rapidly changing patterns of brain activity but it has a low spatial resolution as compared to techniques like fMRI, PET, CT scan, etc. So, one of the motives of this research is to improve the spatial resolution of the EEG signal. Many successful attempts have been made to localise the active neural sources using EEG signals with the introduction of techniques like MNE, LORETA, sLORETA, FOCUSS, etc. But these techniques require a large number of electrodes for correct localization of a few sources. This paper aims at providing a new method for the localization of EEG sources with a fewer electrode. This is achieved by exploiting the second-order statistics to enhance the aperture and solve the EEG localization problem. The comparison of the proposed method with the state-of-the-art methods is done by observing the localization error with variation in SNR, number of snapshots (time samples), number of active sources, and number of electrodes. The results show that the proposed method can detect a greater number of sources with fewer electrodes and with higher accuracy as compared to methods available in the literature. Real -time EEG signal during an arithmetic task is considered and the proposed algorithm clearly shows a sparse activity in the frontal region.

Debating the Drug Policy in Sweden: Stakeholders’ Moral Justifications in Media 2015–2021

Drug-related harms continue to increase globally and governments struggle in search of effective and legitimate countermeasures. The choice between policy options is intertwined with the arguments that dominate drug policy discussions, which in turn are closely related to who has access to the policy debate. In this study, we examine stakeholders’ visibility and moral justifications of argumentation in the Swedish drug policy debate in the media (2015–2021). Justification analysis (JA) is used as a methodological and theoretical tool to illustrate the moral principles behind the claims by the stakeholders. The results show that the most visible stakeholders were politicians, government agencies and molders of public opinion. Furthermore, the stakeholders with successful active attempts to participate in the debate were molders of public opinion, NGOs, and politicians. The silent stakeholders in the media were people who use drugs and significant others. Stakeholders generally revolve around a dividing line regarding the restrictive features of Swedish drug policy, and were divided into proponents, opponents and neutral ones. All stakeholder groups included all three sides, hence reflecting the ingroup dissonance that may explain the continuing deadlock in Swedish drug policy. Justifications that value evidence-based policymaking ( industrial worth) was used in the argumentation by the majority of the stakeholder groups, often combined with other moral justifications. This notion challenges the dichotomy of evidence and values in drug policy debates. Proponents relied more on the justifications that value paternalism ( domestic worth), while opponents leaned toward the justifications valuing civil rights and social justice ( civic worth). The development of Swedish drug policy may depend on the relative strength of these two value positions ( domestic versus civic worth) in society and among stakeholders in power. This study continues the discussion of making contesting values explicit in the drug policy, serving a riveting case for international comparison.

DIACHRONIC AND EXTERNALLY-SCAFFOLDED SELF-CONTROL IN ADDICTION

A restrictive view of self-control identifies exercises of self-control with synchronic intrapsychic processes, and pictures diachronic and externally-scaffolded strategies not as proper instances of self-control, but as clever ways of avoiding the need to exercise that ability. In turn, defenders of an inclusive view of self-control typically argue that we should construe self-control as more than effortful inhibition, and that, on grounds of functional equivalence, all these diverse strategies might be properly described as instances of self-control. In this paper, I take a fresh look at this debate by focusing on cases of addiction. I argue that addicted agents face a paradigmatic sort of self-control challenge, which makes addiction an important test case for theories of self-control. And I discuss evidence that highlights both the unreliability of synchronic intrapsychic strategies and the crucial role that is played by diachronic and externally-scaffolded strategies in successful attempts at achieving abstinence by addicted people. Abstaining addicts are a paradigmatic case of agents who successfully exercise self-control, and they mostly do so by relying on diachronic and externally-scaffolded strategies. This, I argue, lends further support to an inclusive view of self-control.

How to Open the Ring of a Di-ene-Substituted-δ-Valerolactone: From Carbon Dioxide and 1,3-Butadiene to Functional Polyesters.

As a substituted-δ-valerolactone, α-ethylidene-δ-vinyl-δ-valerolactone (EVL) provides a method of utilizing carbon dioxide with 1,3-butadiene to produce functional polymers. Its di-ene-substituted lactone ring was considered inactive in polymerization in the past two decades, while successful polymerization attempts of EVL have been reported very recently. Novel synthetic strategies and functional polymers from EVL have been developed. The ring-opening reactions of EVL and the corresponding polymers as well as the ring-opening (co)polymerizations of EVL and its derivatives are highlighted in this review. The obtained functional polymers with or without facile post-polymerization modification possess unique properties, such as amphipathy, elasticity, peel resistance, etc., allowing for application potential in various fields.

Exploiting graph neural networks to perform finite-difference time-domain based optical simulations

Having an artificial neural network that solves Maxwell’s equations in a general setting is an intellectual challenge and a great utility. Recently, there have been multiple successful attempts to use artificial neural networks to predict electromagnetic fields, given a specific source and interacting material distribution. However, many of these attempts are limited in domain size and restricted to object shapes similar to the learned ones. Here, we overcome these restrictions by using graph neural networks (GNNs) that adapt the propagation scheme of the finite-difference time-domain (FDTD) method to solve Maxwell’s equations for a distinct time step. GNNs yield a significant advantage, i.e., size invariance, over conventional neural network architectures, such as convolutional or linear neural networks. Once trained, a GNN can work on graphs of arbitrary size and connectivity. This allows us to train them on the propagation procedure of electromagnetic fields on small domain sizes and, finally, expand the domain to an arbitrary scale. Moreover, GNNs can adapt to any material shape and work not only on structured grids, such as FDTD, but also on arbitrary meshes. This work may be seen as the first benchmark for field predictions with graph networks and could be expanded to more complex mesh-based optical simulations, e.g., those based on finite elements.

Multiparallel MMT: Faster ISD Algorithm Solving High-Dimensional Syndrome Decoding Problem

The hardness of the syndrome decoding problem (SDP) is the primary evidence for the security of code-based cryptosystems, which are one of the finalists in a project to standardize post-quantum cryptography conducted by the U.S. National Institute of Standards and Technology (NIST-PQC). Information set decoding (ISD) is a general term for algorithms that solve SDP efficiently. In this paper, we conducted a concrete analysis of the time complexity of the latest ISD algorithms under the limitation of memory using the syndrome decoding estimator proposed by Esser et al. As a result, we present that theoretically nonoptimal ISDs, such as May-Meurer-Thomae (MMT) and May-Ozerov, have lower time complexity than other ISDs in some actual SDP instances. Based on these facts, we further studied the possibility of multiple parallelization for these ISDs and proposed the first GPU algorithm for MMT, the multiparallel MMT algorithm. In the experiments, we show that the multiparallel MMT algorithm is faster than existing ISD algorithms. In addition, we report the first successful attempts to solve the 510-, 530-, 540- and 550-dimensional SDP instances in the Decoding Challenge contest using the multiparallel MMT.

Non-targeted authentication of black pepper using a local web platform: Development, validation and post-analytical challenges of a combined NIR spectroscopy and LASSO method

Black pepper is a valuable commodity susceptible to economically motivated adulterations. This contribution describes the proper development, standardization, validation and late-stage validation of a non-targeted method for authentication of black pepper by near-infrared spectroscopy (NIR) coupled to a least absolute shrinkage and selection operator (LASSO). Note that this is the first successful attempt to apply the LASSO method to infrared spectroscopy data. We analysed 150 diverse samples of black pepper supplied by a well-recognized spice trader. A first batch of samples (n = 116) were split into training and test sets and then normalized by multiplicative scatter correction (MSC). While the test set was withheld for further testing of the model, the training set was submitted to the LASSO method with the aim of retrieving the discriminant spectral features and classifying the samples as authentic, exogenously-adulterated or endogenously-adulterated. The model was tested on the test set, achieving an overall accuracy of 94% with very high sensitivity and specificity rates. Furthermore, an R-based local web platform was created for immediate prediction of the samples from raw data. The NIR user simply uploads the raw data to the local web application and MSC normalization on the stored training set and interrogation of the LASSO classifier are performed. The online application facilitates the model testing and enables clear visualization of the outcomes. After the creation of the local web platform, the classifier was then validated with a new batch of independent samples, resulting in the correct prediction of 33/34 samples. The robustness of this non-targeted method and its stability over time was further established, and a late-stage validation of the classifier was successfully performed by an inexperienced user. Finally, the LASSO classifier was successfully challenged with a sample from an international inter-laboratory proficiency test. • A non-targeted method for authentication of black pepper by NIR & LASSO. • A web application was created for direct classification of NIR raw data. • Validation and late-stage challenges of the method were carried out. • Successful participation to an international proficiency test.

Evaluation of a Microsurgery Training Curriculum.

Microsurgery is one of the most challenging areas of surgery with a steep learning curve. To address this educational need, microsurgery curricula have been developed and validated, with the majority focus on technical skills only. The aim of this study was to report on the evaluation of a well-established curriculum using the Kirkpatrick model. A training curriculum was delivered over 5 days between 2017 and 2020 focusing on (1) microscopic field manipulation, (2) knot tying, nondominant hand usage, (3) 3-D models/anastomosis, and (4) tissue experience. The Kirkpatrick model was applied to evaluate the curriculum at four levels: (1) participants' feedback (2) skills development using a validated, objective assessment tool (Global Assessment Score form) and CUSUM charts were constructed to model proficiency gain (3) and (4) assessing skill retention/long-term impact. In total, 155 participants undertook the curriculum, totaling 5,425 hours of training. More than 75% of students reported the course as excellent, with the remaining voting for "good." All participants agreed that the curriculum met expectations and would recommend it. Significant improvement in anastomosis attainment scores between days 1 and 3 (median score 4) and days 4 and 5 (median score 5) (W = 494.5, p = 0.00170). The frequency of errors reduced with successive attempts (chi square = 9.81, p = 0.00174). The steepest learning curve was in anastomosis and patency domains, requiring 11 attempts on average to reach proficiency. In total, 88.5% survey respondents could apply the skills learnt and 76.9% applied the skills learnt within 6 months. Key areas of improvement were identified from this evaluation, and actions to address them were implemented in the following programs. Robust evaluation of curriculum can be applied to microsurgery training demonstrating its efficacy in reducing surgical errors with an improvement in overall technical skills that can extend to impact clinical practice. It allows the identification of areas of improvement, driving the refinement of training programs.

Assessment of the Possibility of Using the Laryngoscopes Macintosh, McCoy, Miller, Intubrite, VieScope and I-View for Intubation in Simulated Out-of-Hospital Conditions by People without Clinical Experience: A Randomized Crossover Manikin Study.

The aim of the study was to evaluate the laryngoscopes Macintosh, Miller, McCoy, Intubrite, VieScope and I-View in simulated out-of-hospital conditions when used by people without clinical experience, and to choose the one that, in the case of failure of the first intubation (FI), gives the highest probability of successful second (SI) or third (TI). For FI, the highest success rate (HSR) was observed for I-View and the lowest (LSR) for Macintosh (90% vs. 60%; p < 0.001); for SI, HSR was observed for I-View and LSR for Miller (95% vs. 66,7%; p < 0001); and for TI, HSR was observed for I-View and LSR for Miller, McCoy and VieScope (98.33% vs. 70%; p < 0.001). A significant shortening of intubation time between FI and TI was observed for Macintosh (38.95 (IQR: 30.1-47.025) vs. 32.4 (IQR: 29-39.175), p = 0.0132), McCoy (39.3 (IQR: 31.1-48.15) vs. 28.75 (IQR: 26.475-35.7), p < 0.001), Intubrite (26.4 (IQR: 21.4-32.3) vs. 20.7 (IQR: 18.3-24.45), p < 0.001), and I-View (21 (IQR: 17.375-25.1) vs. 18 (IQR: 15.95-20.5), p < 0.001). According to the respondents, the easiest laryngo- scopes to use were I-View and Intubrite, while the most difficult was Miller. The study shows that I-View and Intubrite are the most useful devices, combining high efficiency with a statistically significant reduction in time between successive attempts.

Reifying “river”: Unpacking pluriversal possibilities in rejuvenation surrounding the Adi Ganga of Kolkata

Using the River Adi Ganga as the case study and implementing the historical urban political ecology (HUPE) framework, in this article we demonstrate multiple trends and trajectories that comprise city-river relationships. We explore coeval ontologies framing “river,” “riverine space” and “river rejuvenation” schemes, encapsulating “storylines” through the deployment of multi-modal (qualitative) research methodologies to trace and document plural perceptions on the river that was declared to be “dead”—the pillaged stretch that embodied the construction of the metro pillars. Media journalists and activists' narrative, that this act had slaughtered the river and robbed her of her original flows and services, has crafted a deep imprint on the citizens of Kolkata who consider the river as a stinking sink, offering minimal sewerage facilities to the city. Our paper challenges this linear depiction and weaves together positive moments, events and actions that keep the river flowing—shaping and in turn being shaped by (more-than)human actors across long temporal units and scales. We integrate the numerous agential and stakeholder voices attached to the river, shedding light on various (un)successful attempts to revive the river beyond global conceptualizations of what a “river” should be. We believe that the unfolding of this “pluriverse” will forge sustainable understandings of the river's current challenges and existing opportunities toward a collaborative blueprint through knowledge coproduction, stakeholder mobilization and actions. While our empirical frame of reference focuses on micro-realities surrounding a particular river on a specific urban hydroscape, our theoretical conceptualization framings and methodological applications will have potentials to be implemented at scales.

Using model checking to formally verify rendezvous algorithms for robots with lights in Euclidean space

The paper details the first successful attempt at using model checking techniques to verify the correctness of distributed algorithms for robots evolving in a continuous environment. The study focuses on the problem of rendezvous of two robots with lights.There exist many different rendezvous algorithms that aim at finding the minimal number of colors needed to solve rendezvous in various synchrony models (e.g., FSYNC, SSYNC, ASYNC). While these rendezvous algorithms are typically very simple, their analysis and proof of correctness tend to be extremely complex, tedious, and error-prone as impossibility results are based on subtle interactions between the activation schedules of the robots.The paper presents a generic verification model that can be concretely expressed in available software model-checkers. In particular, we explain the subtle design decisions that allow to keep the search space finite and tractable, as well as prove several important theorems that support them. As a sanity check, we use the model to verify several known rendezvous algorithms in six different models of synchrony. In each case, we find that the results obtained from the model checker are consistent with the results known in the literature. The model checker outputs a counter-example execution in every case that is known to fail.In the course of developing and proving the validity of the model, we identified several fundamental theorems, including the ability for a well chosen algorithm and ASYNC scheduler to produce an emerging property of memory in a system of oblivious mobile robots, and why it is not a problem when robots executing the gathering algorithms are equipped with lights.

Third time lucky: An analysis of Paris’ bids for the Olympic Games in 2008, 2012 and 2024

Hosting the Olympic Games has become a unique occasion to implement several projects aimed at upgrading public infrastructure and improving the economic performance of the host city. Thus, some cities are so determined to host the Olympics that they decide to bid multiple times. One of the examples of such a city is Paris, which since the 2000s has submitted its bids three times, for 2008, 2012, and 2024, of which the last attempt turned out to be successful. Based on the above, the main aim of this article is to present the trajectory of changes and developments made by the three successive bid attempts, with an emphasis on the latest successful campaign. This study demonstrates that there are some recurrent ideas, projects, and plans shared by each bid with some modifications to emphasize their uniqueness, novelty, and up-to-date approach. In some aspects, the Paris 2024 bid builds on its previous candidature from 2012 in the field of long-term legacy effects and sustainability. Therefore, there is a consistent action taken by the bid managers and city authorities in terms of using the Olympic Games as a tool for urban regeneration and sports development.