Cavity Optomechanics with Anderson-Localized Optical Modes.

Confining photons in cavities enhances the interaction between light and matter. In cavity optomechanics, this enables a wealth of phenomena ranging from optomechanically induced transparency to macroscopic objects cooled to their motional ground state. Previous work in cavity optomechanics employed devices where ubiquitous structural disorder played no role beyond perturbing resonance frequencies and quality factors. More generally, the interplay between disorder, which must be described by statistical physics, and optomechanical effects has thus far been unexplored. Here, we demonstrate how sidewall roughness in air-slot photonic-crystal waveguides can induce sufficiently strong backscattering of slot-guided light to create Anderson-localized modes with quality factors as high as half a million and mode volumes estimated to be below the diffraction limit. We observe how the interaction between these disorder-induced optical modes and in-plane mechanical modes of the slotted membrane is governed by a distribution of coupling rates, which can exceed g_{o}/2π∼200 kHz, leading to mechanical amplification up to self sustained oscillations via optomechanical backaction. Our Letter constitutes the first steps towards understanding optomechanics in the multiple-scattering regime and opens new perspectives for exploring complex systems with a multitude of mutually coupled degrees of freedom.

Unique profile of academic learning difficulties in Wiedemann-Steiner syndrome.

BACKGROUND: Wiedemann-Steiner syndrome (WSS) is a rare genetic disorder caused by heterozygous variants in KMT2A. To date, the cognitive profile associated with WSS remains largely unknown, although emergent case series implicate increased risk of non-verbal reasoning and visual processing deficits. This study examines the academic and learning concerns associated with WSS based on a parent-report screening measure. PARTICIPANTS AND METHODS: A total of 25 parents of children/adults with a molecularly-confirmed diagnosis of WSS (mean age = 12.85 years, SD = 7.82) completed the Colorado Learning Difficulties Questionnaire (CLDQ), a parent-screening measure of learning and academic difficulties. Parent ratings were compared to those from a normative community sample to determine focal areas in Math, Reading and Spatial skills that may be weaker within this clinical population. RESULTS: On average, parent ratings on the Math (mean Z = -3.08, SD = 0.87) and Spatial scales (mean Z = -2.52, SD = 0.85) were significantly more elevated than that of Reading (mean Z = -1.31, SD = 1.46) (Wilcoxon sign rank test Z < -3.83, P < 0.001), reflecting relatively more challenges observed in these areas. Distribution of parent ratings in Math items largely reflect a positively skewed distribution with most endorsing over three standard deviations below a community sample. In contrast, distributions of parent ratings in Reading and Spatial domains were more symmetric but flat. Ratings for Reading items yielded much larger variance than the other two domains, reflecting a wider range of performance variability. CONCLUSIONS: Parent ratings on the CLDQ suggest more difficulties with Math and Spatial skills among those with WSS within group and relative to a community sample. Study results are consistent with recent case reports on the neuropsychological profile associated with WSS and with Kabuki syndrome, which is caused by variants in the related gene KMT2D. Findings lend support for overlapping cognitive patterns across syndromes, implicating potential common disease pathogenesis.

Engineering nanoscale hypersonic phonon transport.

Controlling vibrations in solids is crucial to tailor their elastic properties and interaction with light. Thermal vibrations represent a source of noise and dephasing for many physical processes at the quantum level. One strategy to avoid these vibrations is to structure a solid such that it possesses a phononic stop band, that is, a frequency range over which there are no available elastic waves. Here we demonstrate the complete absence of thermal vibrations in a nanostructured silicon membrane at room temperature over a broad spectral window, with a 5.3-GHz-wide bandgap centred at 8.4 GHz. By constructing a line-defect waveguide, we directly measure gigahertz guided modes without any external excitation using Brillouin light scattering spectroscopy. Our experimental results show that the shamrock crystal geometry can be used as an efficient platform for phonon manipulation with possible applications in optomechanics and signal processing transduction.

Montreal cognitive assessment (MoCA) is highly correlated with 1-year mortality in hip fracture patients.

Prevalence of cognitive impairment in hip fractures was 86.5%. MoCA is an independent risk factor of mortality. MoCA score of < 15 is correlated with 11.71 times increased risk of mortality. Early attention and caution should be given to these patients for appropriate intervention to decrease mortality rates. INTRODUCTION: Hip fractures rank amongst the top 10 causes of disability and current mortality of hip fractures is high. Objectives were to determine 1) prevalence of cognitive impairment, 2) whether Montreal Cognitive Assessment (MoCA) score was an independent risk factor associated with mortality, 3) MoCA cut-off that result in high risk of mortality. METHODS: This was a cohort study between July 2019 to June 2020. Inclusion criteria were 1) hip fracture, 2) > = 65 years old, and 3) low-energy trauma. Patients undergo assessment for cognitive impairment with MoCA. Prevalence was assessed, MoCA cut-off point, and accuracy of statistical model was evaluated. Logistic regression modelling was used to assess association between mortality and MoCA. RESULTS: There were 260 patients recruited. Two hundred twenty-five patients had MoCA score < 22 signifying cognitive impairment, and 202 patients had MoCA score of < 19. 46 hip fracture patients died at 1-year follow-up. 45 of these patients had MoCA score < 19, and 1 patient had a MoCA > 22. Results showed statistical significance and good model effect (at least 0.8) with MoCA cut-off points between < 15 and < 19 (p < 0.05). After controlling confounding factors, statistical significance still existed in MoCA cut-off point at < 15 (odds ratio (95% CI) = 11.71 (1.14, 120.71); p = 0.04). CONCLUSION: Prevalence of cognitive impairment in hip fractures was 86.5%. MoCA is an independent risk factor of mortality in hip fracture patients. MoCA score of < 15 is correlated with 11.71 times increased risk of mortality at 1-year after a hip fracture. AUC with MoCA score < 15 was 0.948. Early attention and caution should be given to these patients for appropriate intervention to decrease mortality rates.

Quasi-exact solutions for guided modes in two-dimensional materials with tilted Dirac cones.

We show that if the solutions to the (2+1)-dimensional massless Dirac equation for a given one-dimensional (1D) potential are known, then they can be used to obtain the eigenvalues and eigenfunctions for the same potential, orientated at an arbitrary angle, in a 2D Dirac material possessing tilted, anisotropic Dirac cones. This simple set of transformations enables all the exact and quasi-exact solutions associated with 1D quantum wells in graphene to be applied to the confinement problem in tilted Dirac materials such as 8-Pmmn borophene. We also show that smooth electron waveguides in tilted Dirac materials can be used to manipulate the degree of valley polarization of quasiparticles travelling along a particular direction of the channel. We examine the particular case of the hyperbolic secant potential to model realistic top-gated structures for valleytronic applications.

What do psychiatrists think about primary mental health competencies among family doctors? A WPA-WONCA global survey.

People with common mental disorders often seek medical attention from their family doctors. Thus, it is essential for family doctors to possess primary mental health knowledge. The aim of this study was to understand whether psychiatrists endorse the primary mental health competencies identified by the World Organization of Family Doctors and whether they agree that family doctors are demonstrating these competencies. A questionnaire was constructed based on 32 core competencies. Presidents of all World Psychiatric Association member societies were invited to complete the questionnaire or to forward it to local experts. According to the respondents, these competencies are considered relevant yet not sufficiently possessed by typical primary care doctors. Proposals are made to bridge this assumed competency gap.

A multi-site study on the impact of an advance care planning workshop on attitudes, beliefs and behavioural intentions over a 6-month period.

BACKGROUND: This study evaluated the impact of the adapted version of the Respecting Choices® The Living Matters Advance Care Planning (ACP) facilitator training programme on trainees' attitudes on facilitation 6 months post-training. SETTING AND PARTICIPANTS: Two hundred and twenty-one healthcare professionals consisting of doctors, nurses, medical social workers from different training venues in Singapore participated in the first phase of the study (pre- and post) of which 107 participated in the second phase 6 months later (follow-up). METHODS: Participants self-rated their attitudes, beliefs and behavioural intentions through surveys at three time points in an evaluation design that utilised repeated measures one-way ANOVA (pre-, post-, follow-up). Between-group differences were also examined using independent t-test. RESULTS: At follow-up, mean scores increased significantly in understanding, confidence, and competence. Changes in effect sizes were large. Although trainees continued to think that ACP is emotionally draining for facilitators, more than before, facilitation experience was considered pleasant for themselves with the positive change significant and moderate in effect size. Those who had experience completing/initiating ACP significantly held more positive views than those who did not. CONCLUSIONS: The ACP facilitator training programme had lasting effects on enhancing the understanding, competence, and confidence of trainees. Importantly, findings showed that experience in actual facilitation within 6 months after training was important and giving trainees opportunities to facilitate is recommended.

Activity Participation and Perceived Health Status in Patients with Severe Mental Illness: a Prospective Study.

OBJECTIVE: To examine associations between severe mental illness (SMI), general health symptoms, mental wellbeing, and different activity levels in patients with SMI. METHOD: Consecutive patients with SMI referred for occupational therapy were prospectively included. Their hours of activities per day during hospital stay were recorded as <1 hour, 1-3 hours, and >3 hours in three categories: basic self-care activities, interest-based activities, and role-specific activities. Patients were free to join or decline any activities. Patients' somatic and mental health were measured at admission, discharge, and 1 month after discharge using the Brief Psychiatric Rating Scale (BPRS), Patient Health Questionnaire-15 (PHQ-15), Pittsburgh Sleep Quality Index (PSQI), Chinese version of Short Warwick Edinburgh Mental Wellbeing Scale (C-SWEMWBS), and Chinese version of General Activity Motivation Measure (GAMM). RESULTS: 84 patients (35 men and 49 women) aged 16 to 63 years were assessed at the three timepoints. The mean length of hospital stay of current admission was 74.73 days. The most common diagnosis was schizophrenia (n=35), followed by depression (n=15), psychosis (n=14), bipolar affective disorder (n=10), others (n=8), and delusional disorder (n=2). The hours of activities per day was <1 hour in 32 (38.1%) patients, 1-3 hours in 34 (40%) patients, and >3 hours in 18 (21.2%) patients. Improvement in somatic and mental health was positively associated with hours of activities per day. Activities were associated with reduced psychiatric symptoms (measured by BPRS) at discharge (Z = 5.978, p < 0.01). Activities were associated with less somatic complaints (measured by PHQ-15) [χ2 = 23.478, p < 0.01], better sleep quality (measured by PSQI) [χ2 = 14.762, p < 0.01]. The BPRS score for psychiatric symptoms at discharge was inversely associated with C-SWEMWBS score for mental wellbeing (r = -0.233, p = 0.033) and C-GAMM score for activity motivation (r = -0.258, p = 0.018). Basic self-care activities were a predictor for psychiatric symptoms (measured by BPRS) at discharge (adjusted R2 = 0.091, F = 8.496, p = 0.005), whereas a combined group of badminton and Tai Chi was a predictor for general activity motivation (measured by GAMM) at 1 month after discharge (adjusted R2 = 0.047, F = 4.697, p < 0.05), and soccer alone was a predictor for somatic health (measured by PHQ-15) at 1 month after discharge (adjusted R2 = 0.06, F = 5.784, p < 0.05). CONCLUSION: Participating in activities of patients' own choice and interests is positively associated with patients' psychiatric and somatic health and subjective wellbeing. Outdoor soccer has added effect on patients' somatic health. The beneficial effects are maintained at 1 month after discharge. Daily participation of activity meaningful to patients can be a non-pharmacological treatment for patients with SMI to improve somatic and mental health.

Cortical hyperostosis, rare adverse effect of prostaglandin.

We describe here an infant girl with ductal dependent complex cyanotic heart disease, who required prostaglandin infusion for a total of five months prior to Blalock-Taussig shunt procedure. Her alkaline phosphatase activity was raised after seven weeks being on prostaglandin and only dropped to the normal range seven days after discontinuing prostaglandin infusion. During our review at five months old, her limbs were grossly swollen and radiographic examination showed dense periosteal reaction in the long bones. Based on the clinical findings and investigations, she was diagnosed to have cortical hyperostosis, which is an uncommon side effect of prostaglandin. She underwent right Blalock-Taussig Shunt procedure successfully with no major complications. Unfortunately, she succumbed to infection two months after surgery.

Microwave- and heat-based decontamination of N95 filtering facepiece respirators: a systematic review.

BACKGROUND: In pandemics such as COVID-19, shortages of personal protective equipment are common. One solution may be to decontaminate equipment such as facemasks for reuse. AIM: To collect and synthesize existing information on decontamination of N95 filtering facepiece respirators (FFRs) using microwave and heat-based treatments, with special attention to impacts on mask function (aerosol penetration, airflow resistance), fit, and physical traits. METHODS: A systematic review (PROSPERO CRD42020177036) of literature available from Medline, Embase, Global Health, and other sources was conducted. Records were screened independently by two reviewers, and data was extracted from studies that reported on effects of microwave- or heat-based decontamination on N95 FFR performance, fit, physical traits, and/or reductions in microbial load. FINDINGS: Thirteen studies were included that used dry/moist microwave irradiation, heat, or autoclaving. All treatment types reduced pathogen load by a log10 reduction factor of at least three when applied for sufficient duration (>30 s microwave, >60 min dry heat), with most studies assessing viral pathogens. Mask function (aerosol penetration <5% and airflow resistance <25 mmH2O) was preserved after all treatments except autoclaving. Fit was maintained for most N95 models, though all treatment types caused observable physical damage to at least one model. CONCLUSIONS: Microwave irradiation and heat may be safe and effective viral decontamination options for N95 FFR reuse during critical shortages. The evidence does not support autoclaving or high-heat (>90°C) approaches. Physical degradation may be an issue for certain mask models, and more real-world evidence on fit is needed.

Efficacy and safety of disinfectants for decontamination of N95 and SN95 filtering facepiece respirators: a systematic review.

BACKGROUND: Decontaminating and reusing filtering facepiece respirators (FFRs) for healthcare workers is a potential solution to address inadequate FFR supply during a global pandemic. AIM: The objective of this review was to synthesize existing data on the effectiveness and safety of using chemical disinfectants to decontaminate N95 FFRs. METHODS: A systematic review was conducted on disinfectants to decontaminate N95 FFRs using Embase, Medline, Global Health, Google Scholar, WHO feed, and MedRxiv. Two reviewers independently determined study eligibility and extracted predefined data fields. Original research reporting on N95 FFR function, decontamination, safety, or FFR fit following decontamination with a disinfectant was included. FINDINGS AND CONCLUSION: A single cycle of vaporized hydrogen peroxide (H2O2) successfully removes viral pathogens without affecting airflow resistance or fit, and maintains an initial filter penetration of <5%, with little change in FFR appearance. Residual hydrogen peroxide levels following decontamination were within safe limits. More than one decontamination cycle of vaporized H2O2 may be possible but further information is required on how multiple cycles would affect FFR fit in a real-world setting before the upper limit can be established. Although immersion in liquid H2O2 does not appear to adversely affect FFR function, there is no available data on its ability to remove infectious pathogens from FFRs or its impact on FFR fit. Sodium hypochlorite, ethanol, isopropyl alcohol, and ethylene oxide are not recommended due to safety concerns or negative effects on FFR function.

Decontaminating N95 and SN95 masks with ultraviolet germicidal irradiation does not impair mask efficacy and safety.

Inadequate supply of filtering facepiece respirators (FFRs) for healthcare workers during a pandemic such as the novel coronavirus outbreak (SARS-CoV-2) is a serious public health issue. The aim of this study was to synthesize existing data on the effectiveness of ultraviolet germicidal irradiation (UVGI) for N95 FFR decontamination. A systematic review (PROSPERO CRD42020176156) was conducted on UVGI in N95 FFRs using Embase, Medline, Global Health, Google Scholar, WHO feed, and MedRxiv. Two reviewers independently determined eligibility and extracted predefined variables. Original research reporting on function, decontamination, or mask fit following UVGI were included. Thirteen studies were identified, comprising 54 UVGI intervention arms and 58 N95 models. FFRs consistently maintained certification standards following UVGI. Aerosol penetration averaged 1.19% (0.70-2.48%) and 1.14% (0.57-2.63%) for control and UVGI arms, respectively. Airflow resistance for the control arms averaged 9.79 mm H2O (7.97-11.70 mm H2O) vs 9.85 mm H2O (8.33-11.44 mm H2O) for UVGI arms. UVGI protocols employing a cumulative dose >20,000 J/m2 resulted in a 2-log reduction in viral load. A >3-log reduction was observed in seven UVGI arms using >40,000 J/m2. Impact of UVGI on fit was evaluated in two studies (16,200; 32,400 J/m2) and no evidence of compromise was found. Our findings suggest that further work in this area (or translation to a clinical setting) should use a cumulative UV-C dose of 40,000 J/m2 or greater, and confirm appropriate mask fit following decontamination.

The predictors and economic burden of early-, mid- and late-onset cardiac implantable electronic device infections: a retrospective cohort study in Ontario, Canada.

The rate of cardiac implantable electronic device (CIED) infection is increasing with time. We sought to determine the predictors, relative mortality, and cost burden of early-, mid- and late-onset CIED infections. We conducted a retrospective cohort study of all CIED implantations in Ontario, Canada between April 2013 and March 2016. The procedures and infections were identified in validated, population-wide health-care databases. Infection onset was categorized as early (0-30 days), mid (31-182 days) and late (183-365 days). Cox proportional hazards regression was used to assess the mortality impact of CIED infections, with infection modelled as a time-varying covariate. A generalized linear model with a log-link and γ distribution was used to compare health-care system costs by infection status. Among 17 584 patients undergoing CIED implantation, 215 (1.2%) developed an infection, including 88 early, 85 mid, and 42 late infections. The adjusted hazard ratio (aHR) of death was higher for patients with early (aHR 2.9, 95% CI 1.7-4.9), mid (aHR 3.3, 95% CI 1.9-5.7) and late (aHR 19.9, 95% CI 9.9-40.2) infections. Total mean 1-year health costs were highest for late-onset (mean Can$113 778), followed by mid-onset (mean Can$85 302), and then early-onset (Can$75 415) infections; costs for uninfected patients were Can$25 631. After accounting for patient and procedure characteristics, there was a significant increase in costs associated with early- (rate ratio (RR) 3.1, 95% CI 2.3-4.1), mid- (RR 2.8, 95% CI 2.4-3.3) and late- (RR 4.7, 95% CI 3.6-6.2) onset infections. In summary, CIED infections carry a tremendous clinical and economic burden, and this burden is disproportionately high for late-onset infections.

Five Personality Traits in Late-onset Depression in Hong Kong.

OBJECTIVE: This study aimed to examine the association between five personality traits and late-onset depression in Hong Kong older people. METHODS: This cross-sectional study included a convenience sample of 40 older people with late-onset depression (LOD) and 54 non-depressed elderly controls. The patients were assessed using the NEO Five Factor Inventory (for personality), the Hamilton Depression Rating Scale (for depression severity), the Mini-Mental State Examination (for cognitive function), the Lawton Instrumental Activities of Daily Living (for functioning), and the Cumulative Illness Rating Scale (for number of physical illnesses). RESULT: The LOD group had a higher Hamilton Depression Rating Scale score (18.9 vs 3.7, p < 0.001), lower Mini Mental State Examination score (24.9 vs 26.4, p = 0.004), and lower Instrumental Activities of Daily Living scale score (21.9 vs 23.7, p = 0.013). On the NEO Five Factor Inventory, the LOD group had a higher neuroticism score (30.7 vs 17.5, p < 0.001) and lower scores on extraversion (19.0 vs 26.4, p < 0.001), openness (18.9 vs 21.5, p = 0.026), and conscientiousness (29.1 vs 33.8, p < 0.001). Neuroticism was the only significant predictor of LOD (odds ratio = 2.325, p = 0.001) and the only significant factor associated with depression severity (ß = 0.581, p = 0.003). CONCLUSIONS: The personality trait of neuroticism is associated with LOD and its severity. Assessment of personality traits should be included in the assessment of people with depression.

The economic impact of the transition from branded to generic oncology drugs.

Background: Economic evaluations are an integral component of many clinical trials. Costs used in those analyses are based on the prices of branded drugs when they first enter the market. The effect of genericization on the cost-effectiveness (ce) or cost-utility (cu) of an intervention is unknown because economic analyses are rarely updated using the costs of generic drugs. Methods: We re-examined the ce or cu of regimens previously evaluated in Canadian Cancer Trials Group (cctg) studies that included prospective economic evaluations and where genericization has occurred or is anticipated in Canada. We incorporated the new costs of generic drugs to characterize changes in ce or cu. We also determined acceptable cost levels of generic drugs that would make regimens reimbursable in a publicly funded health care system. Results: The four randomized controlled trials included (representing 1979 patients) were cctg br.10 (early lung cancer, adjuvant vinorelbine-cisplatin vs. observation, n = 172), cctg br.21 (metastatic lung cancer, erlotinib vs. placebo, n = 731), cctg co.17 (metastatic colon cancer, cetuximab vs. best supportive care, n = 557), and cctg ly.12 (relapsed or refractory lymphoma, gemcitabine-dexamethasone-cisplatin vs. cytarabine-dexamethasone-cisplatin, n = 619). Since the initial publication of those trials, the genericization of vinorelbine, erlotinib, cetuximab, and cisplatin has taken place or is expected in Canada. Costs of generics improved the ces and cus of treatment significantly. For example, genericization of erlotinib ($1460.25 per 30 days) resulted in an incremental cost-effectiveness ratio (icer) of $45,746 per life-year gained compared with $94,638 for branded erlotinib. Likewise, genericization of cetuximab ($275.80 per 100 mg) produced an icer of $261,126 per quality-adjusted life-year (qaly) gained compared with $299,613 for branded cetuximab. Decreases in the cost of generic cetuximab to $129.39 and $63.51 would further improve the icer to $150,000 and $100,000 per QALY respectively. Conclusions: Genericization of a costly oncology drug can modify the ce and cu of a regimen significantly. Failure to revisit economic analyses with the costs of generics could be a missed opportunity for funding bodies to optimize value-based allocation of health care resources. At current levels, the costs of generics might not be sufficiently low to sustain publicly funded health care systems.

Medical conditions and driving fitness of older Singaporean taxi drivers.

BACKGROUND: Taxi driving has been associated with the risk of various diseases (e.g. cardiovascular disease, hypertension, diabetes, hyperlipaemia, back pain). Little is known about the relationship between health conditions and driving fitness of older taxi drivers who continue to work. AIMS: To investigate the (i) prevalence of medical conditions and (ii) relationship between age and medical conditions, with on-road driving tests in the relicensing process of older taxi drivers aged ≥70 years, prior to the mandatory retirement age of 75 years. METHODS: We analysed retrospectively all relicensing records (N = 855) of taxi drivers aged 70, 73 and 74 years that were submitted from April 2014 to April 2015. RESULTS: All passed their medical fitness screening. Ninety-eight per cent passed their driving tests. Thirty-one per cent, 36% and 24% reported none, one and two medical conditions, respectively. These included hypertension (56%), eye disease (25%; cataracts 19%), diabetes (24%), corrected hearing impairment (14%), hyperlipaemia (12%) and heart disease (9%). Deafness (P < 0.001) was associated with older age. No past medical condition affected driving outcome. CONCLUSION: Older Singaporean taxi drivers were healthy and generally competent drivers. Early effective preventive health screening and modifiable lifestyle intervention are recommended in older taxi drivers.