With the increase of air transportation, some crossing waypoints (CWPs) are becoming bottlenecks in the operation of air traffic networks. This paper presents a CWP operation optimisation framework based on a two-stage optimisation method. First, we considered the interests of airlines and air traffic controllers and established a flight-level dynamic allocation model for the CWP to minimise the flight-level deviation and the number of flight conflicts. A multi-objective, self-adaptive differential evolution-local search hybrid algorithm was used to solve the model in a parallel computing manner. Subsequently, a flight conflict resolution algorithm based on the Monte-Carlo tree search was designed for flight conflicts that existed after the optimisation. Finally, based on real operation data, four experimental scenarios were constructed, and the air traffic operation simulation system was used for experimental validation. For daily traffic and 1.2 times peak traffic scenarios, the average flight-level deviation reduction rates after optimisation were 53% and 39%, and the successful flight conflict resolution rates reached 89% and 75%, respectively. The experimental results showed that this optimisation framework can effectively balance the number of flight conflicts with the efficiency of flight-level usage and directly improve the capacity of the CWP, which can be used as a reference for air traffic control auxiliary decision support systems.

In this behavioral and electrophysiological study, we compare novel word learning, particularly lexical form acquisition, in an immersive virtual reality (VR) context with a picture-word (PW) association context. We also test whether inhibitory control and age of second language acquisition (L2 AoA) have modulating effects. Chinese speakers of L2 English learned two sets of German words, one set in each of the contexts. Behavioral performance from a subsequent recognition task indicated that responses to VR-learned words were faster than PW-leaned words. ERPs revealed that VR-learned words elicited more negative N100 and N200 waveforms than PW-learned words. Moreover, a significant relationship between L2 AoA and N200 amplitude was observed for VR-learned words. Taken together, the results suggest that the multi-sensory, interactive experience simulated by an immersive VR context has a positive effect on early lexical form acquisition of novel words.

Maritime cybersecurity has attracted increasing attention in industrial and academic scope, which may be relevant to the increasing cyber-incidents in the maritime shipping industry. This paper presents a critical review of publications related to cybersecurity in the maritime transportation industry, to explore the current research status and gaps, as wells as to guide new probe avenues by employing bibliometric approaches. With the advantage of bibliometric methods, the research focus and evolution are conformed and visualised. Representative papers are reviewed together to demonstrate maritime cyber-threats recognition and categories, as well as potential consequence assessment and risk mitigation actions recommendation. This paper also created a detailed database that is comprised of attack form, occurring time, targets, purpose, as well as potential results and cost, which has been included in the Appendix and is fully portable and extendible.

Background: Tuberculosis is an airborne disease caused by Mycobacterium Tuberculosis. Intracranial tuberculoma is a rare complication of extrapulmonary tuberculosis due to hematogenous spread to subpial and subependymal regions. Intracranial tuberculoma can occur with or without meningitis. Methods: A 3-year-old male who recently emigrated from Sudan presented to the emergency department with right-sided seizures lasting 30 minutes which were aborted with levetiracetam and midazolam. CT head revealed a multilobulated left supratentorial mass, with solid and cystic components measuring 8.0 x 4.8 x 6.5 cm. The patient had successful surgical resection of the mass which was positive for Mycobacterium Tuberculosis. He was started on rifampin, isoniazid, pyrazinamide, ethambutol, and fluoroquinolone and discharged home in stable condition. Results: Literature review on pediatric intracranial tuberculoma was performed which included 48 studies (n=49). The mean age was 8.8 ± 5.4 years with slight female predilection (59%). Predominant solitary tuberculomas (63%) were preferentially managed with both surgical resection and antitubercular therapy (ATT) compared to multifocal tuberculomas that were preferentially managed with ATT. Conclusions: Intracranial tuberculoma is a rare but treatable cause of space-occupying lesions in children. Clinicians should maintain high-level of suspicion in patients from endemic regions and involve infectious disease service early in patient’s care.

Background: Toxoplasma gondii is a protozoan parasite with the ability to infect any nucleated cell in humans. Most immunocompetent infected individuals are asymptomatic. Latent toxoplasma can become reactivated in immunocompromised individuals though this is exceptionally rare in HIV-negative individuals. Methods: We present the case of a 47-year-old male with chronic immunosuppression secondary to marginal zone lymphoma and steroid therapy. Results: The patient presented to hospital with a 1-week history of word-finding difficulties, intermittent right facial numbness and leg weakness, and tonic-clonic seizures. CT head showed a left temporal heterogenous mass measuring 2.8 × 2.8 × 3.5 cm. Biopsy of the lesion showed Multiple tachyzoites and rare bradyzoites with strong positivity for the toxoplasma specific immunostain. The patient was treated with trimethoprim/sulfamethoxazole which resulted in complete neurologic recovery. Conclusions: Our literature review included 32 cases of cerebral toxoplasmosis in HIV-negative patients with an overall mortality rate of 48%. Cerebral toxoplasmosis has a predilection for immunosuppressed patients with an underlying hematologic malignancy (74%, n= 23). Successful treatment requires early recognition of the disease and prompt treatment with sulfamethoxazole and trimethoprim, pyrimethamine, or sulfadiazine. Patients who recover from acute toxoplasmosis should remain on lifelong suppressive antibiotic therapy to prevent relapse.

Background: Basilar fenestration is a rare congenital anomaly. When present, it is commonly found at the proximal portion of the artery near the vertebrobasilar junction. Methods: This is a case report of a ruptured basilar fenestration aneurysm in a 47-year-male successfully treated with endovascular coiling. Results: A 47-year-old male presented with sudden onset headache, neck pain, blurry vision, nausea, vomiting, and diaphoresis. Cerebral angiogram revealed a saccular basilar fenestration aneurysm located at the vertebrobasilar junction measuring 3.1 x 2.6 x 3.4 mm with a 2.3 mm neck. Multiple coils were placed including Target 360 Nano 2mm x 4 cm (Stryker, Kalamazoo, MI, US), Target 360 Nano 1.5 mm x 2 cm (Stryker, Kalamazoo, MI, US), and Target Helical Nano 1.5 mm x 1 cm (Stryker, Kalamazoo, MI, US). A repeat angiogram revealed complete exclusion of the aneurysm with preservation of both vertebral arteries. Conclusions: A literature review was conducted on basilar fenestration aneurysms which included 158 patients from 39 studies. Overall, complete exclusion of the aneurysm was achieved in 75.8% of cases, with 22.4% of cases having residual flow and 1.8% of cases with unreported exclusion status.

Leakage, deformations, power loss, heat generation in the support seal system and other issues are typical when support seals are developed. The design of the support seal system has progressively evolved over recent decades as part of an ongoing effort to provide effective cooling for the aero engine secondary air system. In particular, oil heat management in the oil chamber has strict requirements, which limit the heat generation of the support seal system. The potential of supporting seal research with an oil system is investigated in this work. The combination of the CFD/FEA method and quantifying the heat generation entering the oil chamber allows for improvements not just to the individual buffer air seal unit, but the oil seal together. The analysis relies on the combination of quantifying heat generation entering the oil chamber to provide a mutual influence of neighbouring labyrinth seals. The mutual influence requires further analysis, considering the thermal deformation of the rotor/stator to provide further accurate geometry parameters in preliminary seal designs. The experimental test was conducted to verify the preliminary CFD-FEA loosely coupled analysis result, which reveals that in a turbine support seal system, the radius of the buffer air seal has a significant influence on the leakage flow rate and power loss of the oil seal, which should take into account the integral influence of the pressure difference of the oil seal caused by the radius change of the buffer air seal and the running clearance of the oil seal.

Background: Neurosurgery is a high-risk specialty with a low margin of error. We aim to assess the risk of neurosurgeons being involved in medicolegal cases in Canada. Methods: This retrospective descriptive study evaluated ten years (2012-2021) of closed legal cases, college cases, and hospital complaints against neurosurgeons with data from the CMPA. Included cases were cranial cases, VP shunts, or cases where a catheter or wire was inserted into the brain. Cases excluded angiography, radiation, ultrasound, or percutaneous procedures. Results: We identified 77 cases (66 urgent or emergent). Neurosurgeons had a significantly higher medicolegal risk than the CMPA surgeon membership, however lower risk compared to all physician specialties. Legal cases accounted for 69% with favourable outcomes in 52%. Forty-one cases involved post-operative complications and 16 cases involved VP shunts. Multiple surgeons or residents could be involved spanning age groups and years in practice. Thirty-four cases had a harmful incident, 41% of these severe. The majority of cases occurred at urban centers. The average case duration was 41 months. Conclusions: This study provides a recent medicolegal analysis of cranial neurosurgery in Canada. We identified areas of common complaints and hope the data can be used to mitigate risk surgical risk in the future.

Background: Chronic subdural hematoma (CSDH) is one of the most encountered conditions seen in neurosurgery. Although mainstay treatment of cSDH has been burr hole drainage, no consensus yet exists on optimal anesthesic technique for surgical treatment between general (GA) and local (LA) anesthesia. Methods: A search was conducted in MEDLINE (1946 to November 11, 2022), Embase (1974 to November 11, 2022), and PubMed (up to November 11, 2022). We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to systematically screen studies. Results: Our literature search identified 521 studies, out of which 20 were included. There were a total of 1750 patients who underwent CSDH drainage under LA. The weighted mean age was 71.0 years, and 27.1% were female. Postoperative complication rate was significantly lower in the LA group (odds ratio 0.44, p = 0.004). The mean operative time (mean difference -29.28 minutes, p <0.0001) and length of admission (mean difference -1.58 days, p = 0.0002) were significantly shorter in the LA group. Conclusions: In this meta-analysis, LA shows benefits in shorter operative time, shorter admission length, and fewer postoperative complications. This makes local anesthesia a less invasive alternative to general anesthesia especially in elderly patients.

Background: In meningiomas, CDKN2A/B deletions are associated with poor outcomes but are rare in most cohorts (1-5%). Large molecular datasets are therefore required to explore these deletions and their relationship to other prognostic CDKN2A alterations. Methods: We utilized multidimensional molecular data of 560 meningiomas from 5 independent cohorts to comprehensively interrogate the spectrum of CDKN2A alterations through DNA methylation, copy number variation, transcriptomics, and proteomics using an integrated molecular approach. Results: Meningiomas with either CDKN2A/B deletions (partial or homozygous loss) or an intact CDKN2A gene locus but elevated mRNA expression (CDKN2Ahigh) both had poor clinical outcomes. Increased CDKN2A mRNA expression was a poor prognostic factor independent of CDKN2A deletion. CDKN2A expression and p16 protein increased with tumor grade and more aggressive molecular and methylation groups. CDKN2Ahigh meningiomas and meningiomas with CDKN2A deletions were enriched for similar cell cycling pathways dysregulated at different checkpoints. p16 immunohistochemistry was unreliable in differentiating between meningiomas with and without CDKN2A deletions, but increased positivity was associated with increased mRNA expression. CDKN2Ahigh meningiomas were associated with gene hypermethylation, Rb-deficiency, and lack of response to CDK inhibition. Conclusions: These findings support the role of CDKN2A mRNA expression as a biomarker of clinically aggressive meningiomas with potential therapeutic implications.

Background: This is a population-based retrospective study of neurologic and cardiac complications of COVID-19 among Chinese and South Asians in Ontario during waves 1-3. Methods: Chinese and South Asians with COVID-19 were identified using a validated surname algorithm and their outcomes of mortality, and cardiac and neurologic complications with those of the general population using multivariable logistic regression models. Results: Compared to the general population (n= 439,977), the Chinese population (n= 15,208) was older (mean age 44.2 vs 40.6 years, P < 0.001) and the South Asian population (n= 46,333) was younger (39.2 years, P < 0.001). The Chinese population had a higher 30-day mortality (odds ratio [OR] 1.44; 1.28-1.61) and more hospitalization or emergency department visits(OR 1.14; 1.09-1.28), with a trend toward a higher incidence of cardiac complications (OR 1.03; 0.87-1.12) and neurologiccomplications (OR 1.23; 0.96-1.58). South Asians had a lower 30-day mortality (OR 0.88; 0.78-0.98) but a higher incidence of hospitalization or emergency department visits (OR 1.17; 1.14-1.20) with a trend toward a lower incidence of cardiac complications(OR 0.76; 0.67-0.87) and neurologic complications (OR 0.89; 0.73-1.09). Conclusions: Ethnicity continues to be an important determinant of mortality, cardiac and neurologic outcomes, and healthcare use among Ontario patients with COVID-19.

One of the most significant issues in hydrodynamic interfacial instabilities is the growth rate of the interfacial perturbations, which plays an important role in both scientific research (e.g. supernova explosion) and engineering applications (e.g. inertial confinement fusion). Yet the underlying mechanisms of such flow phenomena remain unclear or controversial. In this paper the decoupled mechanisms of two effects are found to dominate the interface growth of the single-mode Rayleigh–Taylor instability (RTI) and Richtmyer–Meshkov instability (RMI) via Layzer's potential-flow model. One is the inertial effect induced by the interfacial density gradient and the acceleration, and the other is the frontal distortion effect stemming from interface shape evolution. The former determines the dominant features of interface evolution, while the latter influences the local concavity and convexity of growth rate such as the overshoot phenomenon. These two effects can be approximated as a linearly decoupled analytical solution if their nonlinear interaction term is neglected. With the decoupled solution, the theoretical growth rates agree well with high-fidelity numerical simulation results. The present result indicates that the long-time evolution of fluid interface in both RTI and RMI at all density ratios can be accurately predicted if both inertia and frontal distortion effects are taken into account. Furthermore, the strong dependence of instability evolution on initial amplitude is quantified based on the effects of decoupling, which sheds light on the physical origin of the overshoot phenomenon.

The dynamics of compound drops impacting on a flat substrate is numerically investigated using a ternary-fluid diffuse-interface method, with the aim of assessing the effect of a density difference between the inner and outer droplets (denoted by $\lambda$) on the evolution of the interfaces. With the help of numerical simulations, we find that, at the intermediate stage of drop impact, the inner droplet exhibits a self-similar deformation at $\lambda =1$ and relatively high Weber number, and experiences more or less a uniform acceleration for various $\lambda$. In particular, the acceleration magnitude at $\lambda \ne 1$ can be correlated with the acceleration at $\lambda =1$ and the Atwood number. When the inner droplet is denser than the outer one, a lamella occurs at the spreading front of the inner droplet. We present a scaling analysis of the thickness of the lamella, and the resultant theoretical prediction is in good agreement with numerical results. At the maximal spreading of the compound drop, a bulging structure is formed around the symmetry axis due to the presence of the inner droplet, thereby effectively reducing the liquid supply to the spreading front and leading to a decrease of maximal spreading ratio $\beta _{max}$ as compared with a pure drop. We proposed a corrected Weber number $We^*_\lambda$ by taking account of the combined effects of $\lambda$, volume fraction of the inner droplet, Weber number and morphology of the compound drop. Integrating $We^*_\lambda$ with the universal model of $\beta _{max}$ for impacting pure drops, we successfully build up a new model for predicting the maximal spreading ratio of impacting compound drops with various $\lambda$.