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This study presents novel findings on stochastic electron heating via a random electron cyclotron wave (ECW) in a spherical tokamak. Hard x ray measurements demonstrate the time evolution of hard x ray counts at different energy bands, consistent with predictions from the stochastic heating model. The ECW heating rate shows a positive correlation with applied power, confirming the effectiveness of stochastic heating. Remarkably, the ECW-driven plasma current remains insensitive to ECW incidence angle, consistent with model predictions. The observed stochastic heating of electrons offers potential for exploring innovative non-inductive current drive modes in spherical tokamaks. This research contributes to the understanding of plasma behaviour and motivates the development of new models for non-inductive current drive in fusion devices.
Palmitoyl-protein thioesterase (PPT), involved in the fatty acid synthesis and the de-palmitoylation of protein, was induced under ecological cooling treatment in hydrated lettuce seeds. However, there was no significant difference in fatty acid levels between the control and the cooled samples. To further study the function of PPT, 2-bromopalmitic acid (2-Bp), an inhibitor of protein palmitoylation, was applied during the imbibition of hydrated lettuce seeds, which was followed by slow-cooling treatment (−3°C h−1). The application of 2-Bp (1 mM) significantly increased the survival rate of seeds from 6.70% (control imbibition) to 22.67% (2-Bp imbibition) after slow cooling to −20°C. Differential scanning calorimetry (DSC) analysis indicated that 2-Bp led to earlier onset of ice crystals in the endosperm than the control group. Two-dimensional electrophoresis (2D) confirmed that 2-Bp could promote the hydrolysis of seed globulins and the accumulation of globulin peptides with small molecular weights. High-efficiency hydrolysis of globulin induced by mercaptoethanol improved the freezing tolerance of hydrated lettuce seeds and led to the accumulation of small globulin peptides, which further proved the positive function of small globulin polypeptides in enhancing the freezing tolerance of hydrated lettuce seeds. DSC of small globulin peptides showed that the smaller the molecular weight, the earlier the appearance of ice crystals and the higher the enthalpy of heat release. For the smallest peptides, the 2-Bp-4 in 2-Bp group exhibited higher enthalpy in exothermic peak than the control group (c-4). In conclusion, the hydrolysis of seed globulins and accumulation of small-molecule globulin peptides could be the major reason for improving the freezing tolerance of hydrated seeds after de-palmitoylation treatment.
Research suggests that the COVID-19 pandemic and related stressors have triggered OCS for many individuals. However, the extent to which the pandemic and related stressors have influenced OCS seems to vary by individual factors, with some individuals being at greater risk than others. Despite the well-known role of cognitive inflexibility as a marker of risk for OCS, no study to date has examined the extent to which it influences individual susceptibility to developing OCS during the current pandemic. Toward this aim, the current study examined whether cognitive flexibility moderates whether exposure to COVID-related stressors is associated with OCS. Research suggests that the COVID-19 pandemic and related stressors have triggered OCS for many individuals. However, the extent to which the pandemic and related stressors have influenced OCS seems to vary by individual factors, with some individuals being at greater risk than others. Despite the well-known role of cognitive inflexibility as a marker of risk for OCS, no study to date has examined the extent to which it influences individual susceptibility to developing OCS during the current pandemic.
Toward this aim, the current study examined whether cognitive flexibility moderates whether exposure to COVID-related stressors is associated with OCS.
Participants were 169 students (age = 22 years, 62% female) from two student cohorts at Monash Business School who reported experiencing current OCS symptoms. All cohorts completed an online visual search task to measure flexibility of reward-related attentional capture (as an index of cognitive flexibility; measured using the VMAC-R task) and questionnaires gauging exposure to COVID-related stressors, pre-pandemic OCS, and current/lockdown OCS. A negative binomial regression examined the extent to which a) number of COVID-related stressors, b) cognitive flexibility, and c) their interaction was associated with lockdown OCS, adjusting for pre-COVID OCS.
The interaction between COVID-related stressors and cognitive flexibility was significantly associated with OCS (p = 0.048). Follow-up analyses showed that this interaction was driven by exposure to COVID-related stressors being associated with greater OCS among individuals with high cognitive inflexibility scores only (p = .029). Among cognitively flexible individuals, we did not find a relationship between COVID-related stressors and OCS (p = .470).
The result of this study highlight the role of cognitive flexibility as a potential moderator between COVID events and OCS. Critically, these findings have implications for detecting who is at risk of developing OCS following exposure to COVID-related stressors, and suggest that future interventions aimed at modifying cognitive flexibility may hold promise for boosting resilience against the effects of COVID-related stressors on OCS.
It has been previously identified that levels of peripheral inflammatory proteins, such as cytokines, are altered in people with schizophrenia spectrum disorders (SSD).
As there is considerable inconsistency in the literature with respect to how inflammatory profiles differ between acute and chronic stages of SSD, a systematic review and network meta-analysis was performed.
Records from CINAHL, the Cochrane Central Register of Controlled Trials, EMBASE, PubMed, and PsycINFO were systematically searched from inception until 31 March 2022 for published studies that had measured levels of inflammatory proteins in cases of SSD and healthy controls. Pairwise and network meta-analyses were performed to determine whether there were significant differences in mean peripheral protein concentrations between acute SSD, chronic SSD, and healthy controls.
After application of the screening process, 215 articles were included for data-analysis. One group of markers were consistently elevated (p<0·05) in both acute and chronic SSD, relative to healthy controls; this group comprised interleukin (IL)-1β, IL-1 receptor antagonist (IL-1RA), soluble interleukin-2 receptor (sIL-2R), IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, and high sensitivity C-reactive protein (hsCRP). A second group of markers were inconsistently altered between illness stages: IL-2 and interferon (IFN)-γ were significantly elevated (p<0·05) in acute SSD, whilst IL-4, IL-12 and IFN-γ were significantly decreased (p<0·05) in chronic SSD.
These results indicate that a baseline level of inflammatory protein alteration occurs in SSD throughout the course of illness. This was evident from the group of markers that were consistently elevated in acute and chronic SSD (e.g., IL-6), representing possible trait markers. Moreover, superimposed immune activity may occur in acute SSD, given the group of possible state markers that were increased only in acute illness (e.g., IFN-γ). Further research is required to elucidate whether these peripheral changes are reflected within the central nervous system.
The prolonged COVID-19 pandemic has created unique and complex challenges in operational and capacity planning for pediatric emergency departments, as initial low pediatric patient volumes gave way to unpredictable patient surges during Delta and Omicron variants. Compounded by widespread hospital supply chain issues, staffing shortages due to infection and attrition, and a concurrent pediatric mental health crisis, the surges have pushed pediatric emergency department leaders to re-examine traditionally defined clinical processes, and adopt innovative operational strategies. This study describes the strategic surge response and lessons learned by 3 major freestanding academic pediatric emergency departments in the western United States to help inform current and future pediatric pandemic preparedness.
Studies of Kelvin–Helmholtz (KH) instability have typically modelled the initial flow as an isolated shear layer. In geophysical cases, however, the instability often occurs near boundaries and may therefore be influenced by boundary proximity effects. Ensembles of direct numerical simulations are conducted to understand the effect of boundary proximity on the evolution of the instability and the resulting turbulence. Ensemble averages are used to reduce sensitivity to small variations in initial conditions. Both the transition to turbulence and the resulting turbulent mixing are modified when the shear layer is near a boundary: the time scales for the onset of instability and turbulence are longer, and the height of the KH billow is reduced. Subharmonic instability is suppressed by the boundary because phase lock is prevented due to the diverging phase speeds of the KH and subharmonic modes. In addition, the disruptive influence of three-dimensional secondary instabilities on pairing is more profound as the two events coincide more closely. When the shear layer is far from the boundary, the shear-aligned convective instability is dominant; however, secondary central-core instability takes over when the shear layer is close to the boundary, providing an alternate route for the transition to turbulence. Both the efficiency of the resulting mixing and the turbulent diffusivity are dramatically reduced by boundary proximity effects.
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.
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.
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: 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.
The unstart phenomenon of supersonic inlets caused by backpressure is dangerous for aircraft during flights because it severely reduces the air mass flow rate through the engine. We used unsteady numerical simulations to evaluate the unstart and restart characteristics of a two-dimensional supersonic inlet during rapid backpressure changes. The effects of the depressurisation time and depressurisation value on the inlet flow characteristics and restart features are discussed. The results show that the depressurisation time affects the restart procedure when the back pressure drops from the inlet unstart value to the normal working state value. When the depressurisation time decreases, it becomes easier for the inlet to restart. However, the inlet cannot restart if the depressurisation time is too long. When the depressurisation time and value were large enough, a short buzz period occurred before the inlet restarted. Both the time and value of depressurisation affected the restart characteristics.
This study aimed to compare the pre- and post-operative vestibular and equilibrium functions of patients with cholesteatoma-induced labyrinthine fistulas who underwent different management methods.
Data from 49 patients with cholesteatoma-induced labyrinthine fistulas who underwent one of three surgical procedures were retrospectively analysed. The three management options were fistula repair, obliteration and canal occlusion.
Patients underwent fistula repair (n = 8), canal occlusion (n = 18) or obliteration procedures (n = 23). Patients in the fistula repair and canal occlusion groups suffered from post-operative vertigo and imbalance, which persisted for longer than in those in the obliteration group. Despite receiving different management strategies, all patients achieved complete recovery of equilibrium functions through persistent efforts in rehabilitation exercises.
Complete removal of the cholesteatoma matrix overlying the fistula is reliable for preventing iatrogenic hearing deterioration due to unremitting labyrinthitis. Thus, among the three fistula treatments, obliteration is the optimal method for preserving post-operative vestibular functions.
Body image adjustment is a crucial issue for patients with facial cancer, but body image–specific interventions are scarce. We report results of a novel psychotherapeutic intervention to address body image concerns during acute postoperative recovery following facial reconstructive surgery. Our primary aims were to evaluate the intervention’s feasibility, acceptability, and efficacy on body image concerns, psychological distress, and quality of life (QOL).
Adults with facial cancers who endorsed body image concerns were recruited to participate in a randomized controlled trial. The intervention group participated in 4 in-person counseling sessions. The control group received an educational booklet and a brief phone call. Participants completed measures of body image, distress, and QOL at baseline and at the 4-week follow-up to assess the impact of the intervention. Intervention outcomes were assessed with 2 sample t-tests or Mann–Whitney U tests as appropriate.
Twenty-nine participants completed both the baseline and follow-up assessments. The intervention demonstrated good feasibility with a high retention rate (79%), visit completion rate (81%), and high satisfaction scores (75% reported mean satisfaction score of >3). Intervention did not result in an observed statistically significant difference in reduction in body image dissatisfaction and disturbance, psychological distress, or improvement in QOL compared with the control group. However, intervention resulted in statistically significant difference in perceived social impact (−1 vs. −8.3, p = 0.033) compared to control group.
Significance of results
Our study highlights the potential clinical benefits of a novel psychotherapeutic intervention that targets body image concerns and suggests the need for further evaluation.
Physical activity (PA) may help maintain brain structure and function in aging. Since the intensity of PA needed to effect cognition and cerebrovascular health remains unknown, we examined associations between PA and cognition, regional white matter hyperintensities (WMH), and regional cerebral blood flow (CBF) in older adults.
Forty-three older adults without cognitive impairment underwent magnetic resonance imaging (MRI) and comprehensive neuropsychological assessment. Waist-worn accelerometers objectively measured PA for approximately one week.
Higher time spent in moderate to vigorous PA (MVPA) was uniquely associated with better memory and executive functioning after adjusting for all light PA. Higher MVPA was also uniquely associated with lower frontal WMH volume although the finding was no longer significant after additionally adjusting for age and accelerometer wear time. MVPA was not associated with CBF. Higher time spent in all light PA was uniquely associated with higher CBF but not with cognitive performance or WMH volume.
Engaging in PA may be beneficial for cerebrovascular health, and MVPA in particular may help preserve memory and executive function in otherwise cognitively healthy older adults. There may be differential effects of engaging in lighter PA and MVPA on MRI markers of cerebrovascular health although this needs to be confirmed in future studies with larger samples. Future randomized controlled trials that increase PA are needed to elucidate cause-effect associations between PA and cerebrovascular health.
In a stably stratified shear layer, multiple competing instabilities produce sensitivity to small changes in initial conditions, popularly called the butterfly effect (as a flapping wing may alter the weather). Three ensembles of 15 simulated mixing events, identical but for small perturbations to the initial state, are used to explore differences in the route to turbulence, the maximum turbulence level and the total amount and efficiency of mixing accomplished by each event. Comparisons show that a small change in the initial state alters the strength and timing of the primary Kelvin–Helmholtz instability, the subharmonic pairing instability and the various three-dimensional secondary instabilities that lead to turbulence. The effect is greatest in, but not limited to, the parameter regime where pairing and the three-dimensional secondary instabilities are in strong competition. Pairing may be accelerated or prevented; maximum turbulence kinetic energy may vary by up to a factor of 4.6, flux Richardson number by 12 %–15 % and net mixing by a factor of 2.
Increased access to defensible material wealth is hypothesised to escalate inequality. Market integration, which creates novel opportunities in cash economies, provides a means of testing this hypothesis. Using demographic data collected from 505 households among the matrilineal and patrilineal Mosuo in 2017, we test whether market integration is associated with increased material wealth, whether increased material wealth is associated with wealth inequality, and whether being in a matrilineal vs. patrilineal kinship system alters the relationship between wealth and inequality. We find evidence that market integration, measured as distance to the nearest source of tourism and primary source of household income, is associated with increased household income and ‘modern’ asset value. Both village-level market integration and mean asset value were associated negatively, rather than positively, with inequality, contrary to predictions. Finally, income, modern wealth and inequality were higher in matrilineal communities that were located closer to the centre of tourism and where tourism has long provided a relatively stable source of income. However, we also observed exacerbated inequality with increasing farm animal value in patriliny. We conclude that the forces affecting wealth and inequality depend on local context and that the importance of local institutions is obscured by aggregate statistics drawn from modern nation states.
Unmanned aerial vehicle (UAV) swarm coverage is one of the key technologies for multi-UAV cooperation, which plays an important role in collaborative investigation, detection, rescue and other applications. Aiming at the coverage optimisation problem of UAV in the target area, a collaborative visual coverage control method under positioning uncertainty is presented. First, the visual perception area with imprecise localisation, UAV model and sensor model are created based on the given task environment. Second, a regional division algorithm for the target task area is designed based on the principle of Guaranteed Voronoi (GV) diagram. Then a visual area coverage planning algorithm is designed, in which the task area is allocated to the UAV according to the corresponding weight coefficient of each area, and the input control law is adjusted by the expected state information of the UAV, so that the optimal coverage quality target value and the maximum coverage of the target area can be achieved. Finally, three task scenarios for regional division and coverage planning are simulated respectively, the results show that the proposed area coverage planning algorithm can realise the optimal regional distribution and can obtain more than 90% coverage in different scenarios.
This study assesses governments' long-term non-pharmaceutical interventions upon the coronavirus disease 2019 (COVID-19) pandemic in East Asia. It advances the literature towards a better understanding of when and which control measures are effective. We (1) provide time-varying case fatality ratios and focus on the elderly's mortality and case fatality ratios, (2) measure the correlations between daily new cases (daily new deaths) and each index based on multiple domestic pandemic waves and (3) examine the lead–lag relationship between daily new cases (daily new deaths) and each index via the cross-correlation functions on the pre-whitened series. Our results show that the interventions reduce COVID-19 infections for some periods before the period of the Omicron variant. Moreover, there is no COVID-19 policy lag in Taiwan between daily new confirmed cases and each index. As of March 2022, the case fatality ratios of the elderly group in Japan, Hong Kong and South Korea are 4.69%, 4.72% and 1.48%, respectively, while the case fatality ratio of the elderly group in Taiwan is 25.01%. A government's COVID-19 vaccination distribution and prioritisation policies are pivotal for the elderly group to reduce the number of deaths. Immunising this specific group as best as possible should undoubtedly be a top priority.