Early-detection scheme based on sequential tests for low-latency communications.

We propose an early-detection scheme to reduce communications latency based on sequential tests under finite blocklength regime for a fixed-rate transmission without any feedback channel. The proposed scheme processes observations sequentially to decide in favor of one of the candidate symbols. Such a process stops as soon as a decision rule is satisfied or waits for more samples under a given accuracy. We first provide the optimal achievable latency in additive white Gaussian noise channels for every channel code given a probability of block error. For example, for a rate R = 0.5 and a blocklength of 500 symbols, we show that only 63 % of the symbol time is needed to reach an error rate equal to 10 - 5 . Then, we prove that if short messages can be transmitted in parallel Gaussian channels via a multi-carrier modulation, there exists an optimal low-latency strategy for every code. Next, we show how early detection can be effective with band-limited orthogonal frequency-division multiplexing signals while maintaining a given spectral efficiency by random coding or pre-coding random matrices. Finally, we show how the proposed early-detection scheme is effective in multi-hop systems.

XyloFUNS: Xylocaine to freeze during unpleasant nasopharyngeal swabs in children-a randomized controlled trial.

Objectives: To evaluate the efficacy of intranasal vaporized lidocaine in reducing pain for children undergoing a nasopharyngeal (NP) swab in the Emergency Department (ED). Study Design: A randomized blinded clinical trial was conducted in a paediatric ED. Both participants and the researcher evaluating the primary outcome were blinded. Children aged 6 to 17 years old requiring a NP swab were eligible. Participants were randomly allocated to receive intranasal lidocaine or a sham treatment prior to their NP swab. The primary outcome measure was pain during the swab as assessed by the visual analog scale. Secondary outcome measures were pain using the verbal numeric rating scale, fear using the children fear scale, and adverse effects of the intervention. Results: Eighty-eight participants were enrolled-45 in the lidocaine group and 43 controls. The mean visual analog scale scores for pain were 46 mm in the lidocaine group and 53 mm in the control group (mean difference 7 mm; 95% CI: -5 to 19 mm). No serious adverse events were observed. Conclusions: Intranasal lidocaine administered prior to NP swabs in the ED failed to show an improvement in pain scores for school-aged children and youth.

Lung ultrasound findings in asymptomatic healthy children with asthma.

BACKGROUND: Lung ultrasound (LUS) has been shown to be an effective tool to rapidly diagnose certain causes of pediatric respiratory distress. However, very little is known about LUS findings in pediatric asthma. OBJECTIVES: The primary objective of this study was to characterize LUS findings in a cohort of pediatric patients with a definitive diagnosis of asthma, outside of an asthma exacerbation. METHODS: Eligible patients, aged 6-17 years old and diagnosed with asthma, underwent LUS during an outpatient visit. LUS was conducted using a six-zone scanning protocol. Presence of a LUS artifact was defined by one or more of the following: ≥3 B-lines per intercostal space, pulmonary consolidation, and/or pleural abnormality. Images were interpreted by an expert sonographer blinded to patient clinical characteristics. RESULTS: Fifty-two patients were included. 10/52 (19.2%) patients demonstrated the presence of LUS artifacts: 8 with ≥3 B-lines, 1 with consolidation >1 cm, and 7 with subpleural consolidations <1 cm, 1 with a pleural line abnormality. Artifacts were seen in the right anterior and lateral zones in 60% of participants and were limited to 1-2 intercostal space(s) within one lung zone in all participants. No association was found between presence of LUS artifacts and asthma control or severity. CONCLUSION: To our knowledge, this is the first report of LUS findings in outpatient pediatric asthma. LUS artifacts in asthmatic children can be seen outside of acute exacerbations. Such baseline findings need to be taken into consideration when using LUS for the acute evaluation of a pediatric patient with asthma.

Nasopharyngeal swabs vs. saliva sampling for SARS-CoV-2 detection: A cross-sectional survey of acceptability for caregivers and children after experiencing both methods.

BACKGROUND: Saliva sampling is a promising alternative to nasopharyngeal swabs for SARS-CoV-2 testing, but acceptability data is lacking. We characterize the acceptability of saliva sampling and nasopharyngeal swabs for primary decision makers and their children after experiencing both testing modalities. METHODS: We administered a cross-sectional survey to participants aged 6-to-17 years and their primary decision makers at an Ottawa community COVID-19 testing centre in March 2021. Included were participants meeting local guidelines for testing. Excluded were those identified prior to participation as having inability to complete the consent, sampling, or survey process. Acceptability in multiple hypothetical scenarios was rated using a 5-point Likert scale. Pain was measured using the Faces Pain Scale-Revised (FPS-R). Preference for testing was assessed with direct binary questions. RESULTS: 48 participants and 48 primary decision makers completed the survey. Nasopharyngeal swab acceptability differed between scenarios, ranging 79% [95%CI: 66, 88] to 100% [95%CI: 95, 100]; saliva sampling acceptability was similar across scenarios, ranging 92% [95%CI: 82, 97] to 98% [95%CI: 89, 99]. 58% of youth described significant pain with nasopharyngeal swabbing, versus none with saliva sampling. 90% of children prefer saliva sampling. 66% of primary decision makers would prefer nasopharyngeal swabbing if it were 10% more sensitive. CONCLUSION: Though youth prefer saliva sampling over nasopharyngeal swabs, primary decision makers present for testing remain highly accepting of both. Acceptance of nasopharyngeal swabs, however, varies with the testing indication and is influenced by perceived test accuracy. Understanding factors that influence sampling acceptance will inform more successful testing strategies.

Municipal regulation of cannabis and public health in Canada: A comparison of Alberta, Ontario, and Québec.

Canada legalized nonmedical cannabis in October 2018, but significant variations in municipal regulations exist. This study explored the variations that exist and pondered their potential public health consequences. A comparative analysis was completed on the regulations and guidelines that addressed retailers' location and public consumption in the municipalities of Alberta, Ontario, and Québec. Municipal regulations that addressed the location of retailers were more numerous and extensive in Alberta and Ontario (in the context of provincial private retail models) than in Québec (government-based model). Municipalities in Alberta added more restrictions to public consumption laws as compared to municipalities in Ontario and in Québec. These additions were made to Alberta's and Ontario's provincial-level smoking and vaping bans which used tobacco-inspired frameworks, and to Québec's ban on smoking and vaping in all public spaces. The comparative analysis showed the importance of considering municipal cannabis regulations when studying the impact of legalization, given the significant variations that exist. Policy makers should be made aware of these variations in the regulation of cannabis in order to limit health harms and further social inequalities.

Diverting people who use drugs from the criminal justice system: A systematic review of police-based diversion measures.

BACKGROUND: Previous reviews of the effectiveness of measures to divert those who use drugs from the criminal justice system have focused mainly on post-conviction or post-sentence programs and report mixed results. The present systematic review synthesizes evidence on the effectiveness of police-based diversion measures in reducing criminal offenses and other harms related to drug use and then summarizes evidence from qualitative studies to identify facilitators and barriers associated with the implementation of such measures. METHODS: Eight databases were searched to find evaluations of police-based diversion measures for drug-related offenders. Twenty-seven studies were identified. The vote-count method and the Maryland Scientific Method Scale were used to assess the impact of police-based diversion measures. Themes related to barriers or conditions facilitating the implementation of these measures were extracted from qualitative studies. RESULTS: Evidence from quantitative studies indicates that in general police-based diversion measures are effective in preventing criminal offending and show promising results for improving participants' health and diminishing social costs as well as costs associated with processing drug-related offenses. There was insufficient evidence to draw conclusions about the effect of police-based diversion measures on drug use, drug accessibility, or changes in participants' socioeconomic conditions. Findings from qualitative studies suggest that program acceptance by police officers, constructive intersectoral collaboration, clear eligibility criteria, and timely access to services seem to facilitate the implementation and delivery of police-based diversion measures. CONCLUSION: Police-based diversion measures can be effective in preventing drug-related criminal offenses and harm. Additional research is needed to evaluate their effect on participants' socioeconomic conditions and drug use as well as drug accessibility.

Characterizing pediatric lung ultrasound findings during a chemically induced bronchospasm.

BACKGROUND: Lung ultrasound (LUS) has been shown to be a useful clinical tool in pediatrics, but very little is known about the LUS findings of asthma in children. OBJECTIVES: The primary objective was to characterize LUS findings of pediatric patients before and after a chemically induced bronchospasm. The secondary objective was to evaluate the effect of bronchodilators on LUS findings. METHODS: Eligible children 6-17 years old presenting for a methacholine challenge test (MCT) in a pediatric respiratory clinic were recruited. Patients with viral symptoms were excluded. A six-zone LUS protocol was performed before and after the MCT, and after bronchodilator administration; video recordings were analysed by an expert blinded to the patient characteristics and MCT results. RESULTS: Forty-four patients were included in the study. Five patients had positive LUS findings at baseline. Nine patients out of 29 (31%) had new-onset positive LUS following a reactive MCT. There was a significant association between having a chemically induced bronchospasm and a positive LUS post-MCT (odds ratio [95% confidence interval]: 5.3 [1.0-27.7]; p = 0.05). Among patients who developed positive LUS findings post-MCT, four out of nine returned to having a negative LUS postbronchodilator administration. CONCLUSIONS: This is the first known report of an association between LUS findings and bronchospasm in pediatric patients. It is also the first documentation of resolution of LUS findings postbronchodilator administration. Most LUS findings observed were small and limited to a few intercostal spaces. Further research is required to quantify these findings and evaluate the effect of salbutamol on LUS.

Three sequential outbreaks of Group A Streptococcus over a two-year period at the Canadian Forces Leadership and Recruit School, St. Jean Garrison, Québec.

BACKGROUND: Since December 2016, the basic military training (BMT) facility for the Canadian Armed Forces (CAF) has experienced repeated outbreaks of Group A Streptococcus (GAS). In 2018, a voluntary mass antibiotic prophylaxis (MAP) program was implemented to interrupt GAS transmission among recruits. The objective of this study was to describe the epidemiology of three GAS outbreaks and a period of increased pharyngitis infections at the CAF BMT facility in Québec over a two-year span, and to detail the prevention and control measures implemented to mitigate the risk to recruit health. METHODS: Descriptive data were collected on invasive and severe GAS cases along with laboratory data including genotyping of throat swabs from recruits presenting with pharyngitis. A laboratory-based acute respiratory infection surveillance system was used to aid in monitoring and decision-making. Close contacts of recruits were assessed for asymptomatic GAS carriage and MAP adverse events surveillance was conducted. RESULTS: Three distinct GAS outbreaks occurred at the Canadian Forces Leadership and Recruit School totaling eight invasive (iGAS) and 13 severe (sGAS) cases over two years. All iGAS/sGAS cases, apart from one instructor, were among recruits. The predominant strain in all three outbreaks was type emm6.4. A total of 11,293 recruits received MAP (penicillin G benzathine or azithromycin) between March 7, 2018 and November 18, 2019. There were eight reported serious adverse events related to penicillin administration. CONCLUSION: The CAF BMT facility experienced three GAS outbreaks over the course of two years, and despite the use of enhanced hygiene measures, only MAP has been effective in quelling these outbreaks.

Adverse events following mass antibiotic prophylaxis during a Group A Streptococcus outbreak in the Canadian Forces Leadership and Recruit School.

BACKGROUND: Between December 2016 and March 2018, two outbreaks of Group A Streptococcus (GAS) infection occurred at the Canadian Forces Leadership and Recruit School. A voluntary mass antibiotic prophylaxis (MAP) program was implemented in March 2018, to interrupt an ongoing GAS outbreak, and to prevent future outbreaks. METHODS: Instructors and recruits were offered a one-time intramuscular injection of 1.2 million units penicillin G benzathine (PGB). Individuals with a penicillin allergy were offered azithromycin; 500 mg orally once weekly for four consecutive weeks. Instructors and recruits were also asked to complete a voluntary and anonymous survey one week after receipt of MAP, to detect MAP-related adverse events. RESULTS: MAP was offered to 2,749 individuals; 2,707 of whom agreed to receive it (98.5% uptake). The majority of personnel experienced adverse events in the days following MAP; 92.3% of personnel who received PGB reported localized pain at the injection site, and 70.2% of personnel who received azithromycin reported gastrointestinal symptoms. However, only five cases of serious adverse events were reported, and less than 1% of recruits could not complete their basic military training course because of MAP-related adverse events. CONCLUSION: The MAP program implemented in March 2018 was the first of its kind in the Canadian Armed Forces, and the largest single use of PGB in a defined group in Canada. It resulted in very few serious adverse events and with minimal impact on military recruits' successful completion of recruit training.

Analysis and Experimental Validation of Efficient Coded OFDM for an Impulsive Noise Environment.

The importance of synergy with industry lies in the possibility of experimental validation of the work research results. With Software-Defined Radio (SDR) platforms, it is possible to implement a physical layer and to have tests with hardware in a real environment. In this paper, we investigate the validation of an impulsive noise resistant physical layer based on Orthogonal Frequency Division Multiplexing (OFDM) and an interesting concatenation of forward error correcting codes: Rank metric Code (RC) and Convolutional Code (CC). We fully design and implement a new block namely RC Encoder + WiFi Mapper in GNU Radio, which acts as a forward error correcting code to mitigate impulsive noise occurring in substations. After showing by simulations that using this coding scheme is very efficient in mitigating the bursty nature of impulsive noise, we then confirm that the same performance is maintained even with various impulsive voltages and experimental scenarios, which confirms the high performance of the proposed approach.

Peripheral human CD4+CD8+ T lymphocytes exhibit a memory phenotype and enhanced responses to IL-2, IL-7 and IL-15.

CD4+CD8+ T lymphocytes account for 1-2% of circulating human T lymphocytes, but their frequency is augmented in several diseases. The phenotypic and functional properties of these T lymphocytes are still ill-defined. We performed an ex vivo characterization of CD4+CD8+ T lymphocytes from the blood of healthy individuals. We observed that CD4+CD8+ T lymphocytes exhibit several characteristics associated with memory T lymphocytes including the expression of chemokine receptors (e.g. CCR7, CXCR3, CCR6) and activation markers (e.g. CD57, CD95). Moreover, we showed that a greater proportion of CD4+CD8+ T lymphocytes have an enhanced capacity to produce cytokines (IFNγ, TNFα, IL-2, IL-4, IL-17A) and lytic enzymes (perforin, granzyme B) compared to CD4+ and/or CD8+ T lymphocytes. Finally, we assessed the impact of three key cytokines in T cell biology on these cells. We observed that IL-2, IL-7 and IL-15 triggered STAT5 phosphorylation in a greater proportion of CD4+CD8+ T lymphocytes compared to CD4 and CD8 counterparts. We demonstrate that CD4+CD8+ T lymphocytes from healthy donors exhibit a phenotypic profile associated with memory T lymphocytes, an increased capacity to produce cytokines and lytic enzymes, and a higher proportion of cells responding to key cytokines implicated in T cell survival, homeostasis and activation.

A randomized, single-blind, controlled, parallel assignment study of exercise versus education as adjuvant in the treatment of peripheral neuropathic pain.

OBJECTIVE: Some forms of chronic pain are receptive to exercise therapy for maintenance of pain relief. We evaluated the impact of a balanced exercise program in the management of human peripheral neuropathic pain compared with an educational intervention. METHODS: This was a single-center, randomized, single-blind, controlled study using an intention-to-treat protocol. Patients with confirmed neuropathic pain and a pain score ≥4 (0 to 10 scale) on visual analog scale (VAS) continued their regular pain therapies and were randomized to 6 months of either a balanced exercise program or an educational program. VAS for pain severity was the primary outcome variable. Characteristics of pain, function, mood, anxiety, sleep, and quality of life along with Single Stage Treadmill Walking Test calculating maximal oxygen consumption (VO2) formed the secondary outcome measures. RESULTS: Seventy-eight patients were screened and 54 participated, with 28 randomized to exercise and 26 randomized to education. A total of 19 (68%) and 20 patients (77%) completed exercise and education, respectively. VAS scores improved 17% for the exercise group as compared with 9% for the education group (P=0.08). The only secondary outcome measure demonstrating improvement was VO2, which improved in exercise participants (25.6±4.5 mL/kg/min at baseline vs. 28.9±3.8 mL/kg/min at 6 mo). DISCUSSION: A balanced exercise program was beneficial for exercise capacity, but produced only a medium-sized effect without statistical significance. A small sample size and unexpectedly high dropout rates may have limited our ability to demonstrate statistically significant improvement in pain relief.

Influencing public policies: Two (very good) reasons to look toward scientific knowledge in public policy.

The healthy public policy movement rests on the belief that a range of public policies should be at least partly informed by evidence demonstrating the positive effects of these policies on population health, health inequalities and their determinants. In order to address certain difficulties that the movement faces, knowledge produced in various scientific disciplines regarding public policies may provide some valuable guidance. In this short commentary, we examine how knowledge from the scientific disciplines investigating public policies makes it possible to address two difficulties in the development of healthy public policies: 1) adequately anticipating the effects of public policies, and 2) assessing the political viability of the policies being promoted. Since urban traffic policies are of interest to most of the other contributors to this supplement, we use examples from this field to illustrate some of our points.

A family of Nyquist pulses for coherent optical communications.

A new family of Nyquist pulses for coherent optical single carrier systems is introduced and is shown to increase the nonlinearity tolerance of dual-polarization (DP)-QPSK and DP-16-QAM systems. Numerical investigations for a single-channel 28 Gbaud DP-16-QAM long-haul system without optical dispersion compensation indicate that the proposed pulse can increase the reach distance by 26% and 19%, for roll-off factors of 1 and 2, respectively. In multi-channel transmissions and for a roll-off factor of 1, a reach distance increase of 20% is reported. Experimental results for DP-QPSK and DP-16-QAM systems at 10 Gbaud confirm the superior nonlinearity tolerance of the proposed pulse.