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Electronic frequency mixers are fundamental building blocks of electronic systems. Harmonic frequency mixing in particular enables broadband electromagnetic signal analysis across octaves of spectrum using a single local oscillator. However, conventional harmonic frequency mixers do not operate beyond hundreds of gigahertz to a few terahertz. If extended to the petahertz scale in a compact and scalable form, harmonic mixers would enable field-resolved optical signal analysis spanning octaves of spectra in a monolithic device without the need for frequency conversion using nonlinear crystals. Here, we demonstrate lightwave-electronic harmonic frequency mixing beyond 0.350 PHz using plasmonic nanoantennas. We demonstrate that the mixing process enables complete, field-resolved detection of spectral content far outside that of the local oscillator, greatly extending the range of detectable frequencies compared to conventional heterodyning techniques. Our work has important implications for applications where optical signals of interest exhibit coherent femtosecond-scale dynamics spanning multiple harmonics.
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Gender-based violence (GBV) poses a significant concern in the construction and natural resources industries, where women, due to lower social status and integration, are at heightened risk. This systematic review aimed to identify the prevalence and experience of GBV in the construction and natural resources industries. A systematic search across databases including PubMed, OVID, Scopus, Web of Science, and CINAHL was conducted. The Risk of Bias Instrument for Cross-sectional Surveys of Attitudes and Practices by McMaster University and the Critical Appraisal of Qualitative Studies by the Center for Evidence Based Medicine at the University of Oxford were used to assess the studies included in the review. Six articles were included after full-text analysis. GBV was reported in the construction, mining, urban forestry, and arboriculture sectors. Workplace GBV was measured differently across the studies, and all studies examined more than one form of GBV. The main forms of GBV discussed in these studies were discrimination, sexual harassment, and sexism. The studies provided some insight for demographic factors that may or may not be associated with GBV, such as age, region of work, and number of years working in the industry. The review also suggests that workplace GBV has a negative impact on mental health and well-being outcomes, such as higher levels of stress and lower job satisfaction. The current research has not established the effectiveness of interventions, tools, or policies in these workplaces. Thus, additional research should include intervention studies that aim to minimize or prevent GBV in male-dominated workplaces. The current study can bring awareness and acknowledgement towards GBV in the workplace and highlight the importance of addressing it as this review outlines the negative consequences of GBV on mental health and well-being in these male-dominated industries.
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Newborn screening (NBS) is an important public health program that aims to identify pre-symptomatic healthy babies that will develop significant disease if left undiagnosed and untreated. The number of conditions being screened globally is expanding rapidly in parallel with advances in technology, diagnosis, and treatment availability for these conditions. In Hong Kong, NBS for inborn errors of metabolism (NBSIEM) began as a pilot program in October 2015 and was implemented to all birthing hospitals within the public healthcare system in phases, with completion in October 2020. The number of conditions screened for increased from 21 to 24 in April 2016 and then to 26 in October 2019. The overall recruitment rate of the NBS program was 99.5%. In the period between October 2015 and December 2022, 125,688 newborns were screened and 295 were referred back for abnormal results. The recall rate was reduced from 0.26% to 0.12% after the implementation of second-tier testing. An inherited metabolic disorder (IMD) was eventually confirmed in 47 infants, making the prevalence of IMD in Hong Kong 1 in 2674. At the time of the NBS result, 78.7% of the newborns with IMD were asymptomatic. There were two deaths reported: one newborn with methylmalonic acidemia cobalamin B type (MMACblB) died after the initial crisis and another case of carnitine palmitoyltransferase II deficiency (CPTII) died at 18 months of age after metabolic decompensation. The most common IMD noted were disorders of fatty acid oxidation metabolism (40%, 19 cases), closely followed by disorders of amino acid metabolism (38%, 18 cases), with carnitine uptake defect (19.1%, 9 cases) and citrullinemia type II (17%, 8 cases) being the two most common IMD picked up by the NBSIEM in Hong Kong. Out of the all the IMDs identified, 19.1% belonged to diverse ethnic groups. False negative cases were reported for citrullinemia type II and congenital adrenal hyperplasia during this period.
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In this study, we evaluated the implementation of a second-tier genetic screening test using an amplicon-based next-generation sequencing (NGS) panel in our laboratory during the period of 1 September 2021 to 31 August 2022 for the newborn screening (NBS) of six conditions for inborn errors of metabolism: citrullinemia type II (MIM #605814), systemic primary carnitine deficiency (MIM #212140), glutaric acidemia type I (MIM #231670), beta-ketothiolase deficiency (#203750), holocarboxylase synthetase deficiency (MIM #253270) and 3-hydroxy-3-methylglutaryl-CoA lyase deficiency (MIM # 246450). The custom-designed NGS panel can detect sequence variants in the relevant genes and also specifically screen for the presence of the hotspot variant IVS16ins3kb of SLC25A13 by the copy number variant calling algorithm. Genetic second-tier tests were performed for 1.8% of a total of 22,883 NBS samples. The false positive rate for these six conditions after the NGS second-tier test was only 0.017%, and two cases of citrullinemia type II would have been missed as false negatives if only biochemical first-tier testing was performed. The confirmed true positive cases were citrullinemia type II (n = 2) and systemic primary carnitine deficiency (n = 1). The false positives were later confirmed to be carrier of citrullinemia type II (n = 2), carrier of glutaric acidemia type I (n = 1) and carrier of systemic primary carnitine deficiency (n = 1). There were no false negatives reported. The incorporation of a second-tier genetic screening test by NGS greatly enhanced our program's performance with 5-working days turn-around time maintained as before. In addition, early genetic information is available at the time of recall to facilitate better clinical management and genetic counseling.
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INTRODUCTION: Emergency airway management is a common and critical task EMS clinicians perform in the prehospital setting. A new set of evidence-based guidelines (EBG) was developed to assist in prehospital airway management decision-making. We aim to describe the methods used to develop these EBGs. METHODS: The EBG development process leveraged the four key questions from a prior systematic review conducted by the Agency for Healthcare Research and Quality (AHRQ) to develop 22 different population, intervention, comparison, and outcome (PICO) questions. Evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework and tabulated into the summary of findings tables. The technical expert panel then used a rigorous systematic method to generate evidence to decision tables, including leveraging the PanelVoice function of GRADEpro. This process involved a review of the summary of findings tables, asynchronous member judging, and online facilitated panel discussions to generate final consensus-based recommendations. RESULTS: The panel completed the described work product from September 2022 to April 2023. A total of 17 summary of findings tables and 16 evidence to decision tables were generated through this process. For these recommendations, the overall certainty in evidence was "very low" or "low," data for decisions on cost-effectiveness and equity were lacking, and feasibility was rated well across all categories. Based on the evidence, 16 "conditional recommendations" were made, with six PICO questions lacking sufficient evidence to generate recommendations. CONCLUSION: The EBGs for prehospital airway management were developed by leveraging validated techniques, including the GRADE methodology and a rigorous systematic approach to consensus building to identify treatment recommendations. This process allowed the mitigation of many virtual and electronic communication confounders while managing several PICO questions to be evaluated consistently. Recognizing the increased need for rigorous evidence evaluation and recommendation development, this approach allows for transparency in the development processes and may inform future guideline development.
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Manuseio das Vias Aéreas , Serviços Médicos de Emergência , Humanos , Serviços Médicos de Emergência/métodos , Serviços Médicos de Emergência/normas , Manuseio das Vias Aéreas/métodos , Manuseio das Vias Aéreas/normas , Medicina Baseada em Evidências , Guias de Prática Clínica como Assunto , Estados UnidosRESUMO
INTRODUCTION: Unicompartmental knee arthroplasty (UKA) is an effective surgical treatment for medial compartment arthritis of the knee, yet surgical outcomes are directly related to surgical execution. Robotic arm-assisted surgery aims to address these difficulties by allowing for detailed preoperative planning, real-time intraoperative assessment and haptic-controlled bone removal. This study aimed to compare the clinical and radiological outcomes between conventional manual mobile bearing and robot arm-assisted fixed bearing medial UKA in our local population. MATERIALS AND METHODS: This is a retrospective case-control study of 148 UKAs performed at an academic institution with a minimum of 1-year follow-up. 74 robotic arm-assisted UKAs were matched to 74 conventional UKAs via propensity score matching. Radiological outcomes included postoperative mechanical axis and individual component alignment. Clinical parameters included a range of motion, Knee Society knee score and functional assessment taken before, 6 and 12 months after the operation. RESULTS: Robot arm-assisted UKA produced a more neutral component coronal alignment in both femoral component (robotic -0.2 ± 2.8, manual 2.6 ± 2.3; P = 0.043) and tibial component (robotic -0.3 ± 4.0, manual 1.7 ± 5.3; P < 0.001). While the postoperative mechanical axis was comparable, robot arm-assisted UKA demonstrated a smaller posterior tibial slope (robotic 5.7 ± 2.7, manual 8.2 ± 3.3; P = 0.02). Clinical outcomes did not show any statistically significant differences. CONCLUSION: Compared with conventional UKA, robotic arm-assisted UKA demonstrated improved component alignment and comparable clinical outcomes. Improved radiological accuracy with robotic-arm assistance demonstrated promising early results.
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Dried blood spot (DBS) cards from newborn screening (NBS) programs represent a wealth of biological data. They can be stored easily for a long time, have the potential to support medical and public health research, and have secondary usages such as quality assurance and forensics, making it the ideal candidate for bio-banking. However, worldwide policies vary with regard to the duration of storage of DBS cards and how it can be used. Recent advances in genomics have also made it possible to perform extended genetic testing on DBS cards in the newborn period to diagnose both actionable and non-actionable childhood and adult diseases. Both storage and secondary uses of DBS cards raise many ethical, clinical, and social questions. The openness of the key stakeholders, namely, parents and healthcare providers (HCPs), to store the DBS cards, and for what duration and purposes, and to extended genetic testing is largely dependent on local cultural-social-specific factors. The study objective is to assess the parents' and HCPs' awareness and receptivity toward DBS retention, its secondary usage, and extended genetic testing. A cross-sectional, self-administrated survey was adopted at three hospitals, out of which two were public hospitals with maternity services, between June and December 2022. In total, 452 parents and 107 HCPs completed and returned the survey. Overall, both HCPs and parents were largely knowledgeable about the potential benefits of DBS card storage for a prolonged period and its secondary uses, and they supported extended genetic testing. Knowledge gaps were found in respondents with a lower education level who did not know that a DBS card could be stored for an extended period (p < 0.001), could support scientific research (p = 0.033), and could aid public health research, and future policy implementation (p = 0.030). Main concerns with regard to DBS card storage related to potential privacy breaches and anonymity (Parents 70%, HCPs 60%). More parents, compared to HCPs, believed that storing DBS cards for secondary research does not lead to a reciprocal benefit to the child (p < 0.005). Regarding extended genetic testing, both groups were receptive and wanted to know about actionable childhood- and adult-onset diseases. More parents (four-fifths) rather than HCPs (three-fifths) were interested in learning about a variant with unknown significance (p < 0.001). Our findings report positive support from both parents and HCPs toward the extended retention of DBS cards for secondary usage and for extended genetic testing. However, more efforts to raise awareness need to be undertaken in addition to addressing the ethical concerns of both parents and HCPs to pave the way forward toward policy-making for DBS bio-banking and extended genetic testing in Hong Kong.
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BACKGROUND: To date, there has been little research on the effect of safe consumption site and community-based naloxone programs on regional opioid-related emergency department visits and deaths. We sought to determine the impact of these interventions on regional opioid-related emergency department visit and death rates in the province of Alberta. METHODS: We used a retrospective observational design, via interrupted time series analysis, to assess municipal opioid-related emergency department visit volume and opioid-related deaths (defined by poisoning and opioid use disorder). We compared rates before and after program implementation in individual Alberta municipalities and province-wide after safe consumption site (March 2018 to October 2018) and community-based naloxone (January 2016) program implementation. RESULTS: A total of 24 107 emergency department visits and 2413 deaths were included in the study. After safe consumption site opening, we saw decreased opioid-related emergency department visits in Calgary (level change -22.7 [-20%] visits per month, 95% confidence interval [CI] -29.7 to -15.8) and Lethbridge (level change -8.8 [-50%] visits per month, 95% CI -11.7 to -5.9), and decreased deaths in Edmonton (level change -5.9 [-55%] deaths per month, 95% CI -8.9 to -2.9). We observed increased emergency department visits after community-based naloxone program implementation in urban Alberta (level change 38.9 [46%] visits, 95% CI 33.3 to 44.4). We also observed an increase in urban opioid-related deaths (level change 9.1 [40%] deaths, 95% CI 6.7 to 11.5). INTERPRETATION: The results of this study suggest differences exist between municipalities employing similar interventions. Our results also suggest contextual variation; for example, illicit drug supply toxicity may modify the ability of a community-based naloxone program to prevent opioid overdose without a thorough public health response.
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Analgésicos Opioides , Overdose de Drogas , Humanos , Analgésicos Opioides/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Overdose de Drogas/prevenção & controle , Naloxona/uso terapêutico , Serviço Hospitalar de EmergênciaRESUMO
INTRODUCTION: Injured adolescents may be treated at pediatric trauma centres (PTCs) or adult trauma centres (ATCs). Patient and parent experiences are an integral component of high-quality health care and can influence patient clinical trajectory. Despite this knowledge, there is little research on differences between PTCs and ATCs with respect to patient and caregiver-reported experience. We sought to identify differences in patient and parent-reported experiences between the regional PTC and ATC using a recently developed Patient and Parent-Reported Experience Measure. METHODS: We prospectively enrolled patients (caregivers) aged 15-17 (inclusive), admitted to the local PTC and ATC for injury management (01/01/2020 - 31/05/2021) We provided a survey 8-weeks post-discharge to query acute care and follow-up experience. Patient and parent experiences were compared between the PTC and ATC using descriptive statistics, chi-square tests for categorical and independent t-tests for continuous variables. RESULTS: We identified 90 patients for inclusion (51 PTC, and 39 ATC). From this population, we had 77 surveys (32 patient and 35 caregiver) completed at the PTC, and 41 (20 patient and 21 caregiver) at the ATC. ATC patients tended to be more severely injured. We identified few differences in reported experience on the patient measure but identified lower ratings from caregivers of adolescents treated in ATCs for the domains of information and communication, follow-up care, and overall hospital scores. Patients and parents reported poorer family accommodation at the ATC. CONCLUSION: Patient experiences were similar between centres. However, caregivers report poorer experiences at the ATC in several domains. These differences are multifaceted, and may reflect differing patient volumes, effects of COVID-19, and healthcare paradigms. However, further work should target information and communication improvement in adult paradigms given its impact on other domains of care.
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COVID-19 , Centros de Traumatologia , Humanos , Criança , Adolescente , Adulto , Assistência ao Convalescente , Escala de Gravidade do Ferimento , Alta do PacienteRESUMO
PURPOSE: Tether breakage is the most common complication of Vertebral Body Tethering (VBT) occurring in up to 52% of Adolescent Idiopathic Scoliosis (AIS) patients and risks continued progression and revision. Radiographical diagnosis of tether breakage is commonly defined by a 5° increase in inter-screw angle and associates breakage with loss of correction. However, the sensitivity of this method was 56% only, suggesting that tethers can break without an increase in angulation, which was supported by other studies. To our knowledge, current literature lacks a method merely focusing on the diagnosis of tether breakage radiographically that does not associate the breakages with loss of correction. METHODS: This was a retrospective review of prospectively collected data of AIS patients who underwent VBT. The "inter-screw index" is defined as the percentage increase in inter-screw distance since post-op, with ≥ 13% increase defined as tether breakage as suggested by our mechanical tests. CTs were reviewed to identify the breakages and compared with inter-screw angle and inter-screw index. RESULTS: 94 segments from 13 CTs were reviewed, and 15 tether breakages were identified. Use of inter-screw index correctly identified 14 breakages (93%), whereas ≥ 5° increase in inter-screw angle only identified 12 breakages (80%). CONCLUSION: Use of inter-screw index is proven to be more sensitive than inter-screw angle in identifying tether breakages. Therefore, we propose the use of inter-screw index to diagnose tether breakages radiographically. Tether breakages were not necessarily accompanied by a loss of segmental correction leading to an increase in inter-screw angle, especially after skeletal maturity. LEVEL OF EVIDENCE: Level 3.
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Cifose , Escoliose , Adolescente , Humanos , Vértebras Torácicas/cirurgia , Parafusos Ósseos , Escoliose/cirurgia , Radiografia , Cifose/cirurgiaRESUMO
Tranexamic acid (TXA) is a common haemorrhage control agent in both emergency department (ED) settings and intra-operatively. While efficacy and potential harms are well-studied, there are no overviews of reviews completed on TXA efficacy in the ED setting. We set out to provide an overview of systematic reviews on TXA efficacy in trauma, gastrointestinal bleeding, and subarachnoid haemorrhage in the ED setting, with outcomes including short and long-term mortality, thromboembolic (TE) events, and whether bleeding continued. Our review is guided by the PRIOR statement. We searched Pubmed, Medline, and EMBASE using broad search terms for systematic reviews, and calculated pooled relative-risk ratios using random and fixed-effects modelling from these studies. A risk-of-bias assessment was also completed for each review. We identified 13 systematic reviews for inclusion, with a variety of different outcomes. We identified improvements in 24-h mortality for trauma (RR 0.88, 95% CI 0.84-0.92) and gastrointestinal bleeds (RR 0.30, 95% CI 0.23-0.39), and decreased long-term gastrointestinal bleed mortality (RR 0.57, 95% CI 0.48-0.69). We also identified an increase in TE risk in gastrointestinal bleeding scenarios (RR 1.45, 95% CI 1.09-1.94), but no other clinical scenarios. TXA is effective in reducing mortality following trauma and gastrointestinal bleeds, however, there is limited evidence at this time to support TXA administration in the context of subarachnoid haemorrhage. TE risk is elevated when used in gastrointestinal bleeds. Selective use in high-risk patients may be warranted. TXA should strongly be considered in management in ED and prehospital settings.
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Antifibrinolíticos , Medicina de Emergência , Hemorragia Subaracnóidea , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/uso terapêutico , Antifibrinolíticos/uso terapêutico , Revisões Sistemáticas como Assunto , Hemorragia Gastrointestinal/tratamento farmacológicoRESUMO
BACKGROUND: There is a high prevalence of unconfirmed penicillin allergy, which is associated with a multitude of adverse clinical outcomes. With the overwhelming burden of currently incorrect labels and the lack of allergy specialist services, new delabeling strategies are urgently needed. OBJECTIVE: To assess the effectiveness, safety, and real-world outcomes of a nurse-led, protocol-driven evaluation of penicillin allergy, the Hong Kong Drug Allergy Delabelling Initiative (HK-DADI). METHODS: Adult patients with suspected penicillin allergy were recruited into HK-DADI. Allergy and postdelabeling outcomes were retrospectively compared between patients evaluated via HK-DADI or traditional allergist evaluation. RESULTS: A total of 312 completed penicillin allergy evaluation: 84 (27%) and 228 (73%) via HK-DADI and traditional pathways, respectively. Overall, 280 penicillin allergies were delabeled (90%). The delabeling rate between HK-DADI and traditional pathways was similar (90% vs 89%; P = .796). Among patients of the HK-DADI pathway, the delabeling rate was significantly higher among low-risk (LR) compared with non-LR patients (97% vs 77%; P = .010). Skin tests did not add diagnostic value among LR patients. No patients developed severe or systemic reactions during the evaluation. Upon 6- to 12-month follow-up (median, 10 months), 123 patients experienced infective episodes (44%) and 63 used penicillins again after delabeling (23%). This proportion was significantly higher in patients who were delabeled via HK-DADI compared with the traditional pathway (32% vs 19%; P = .026). CONCLUSIONS: The Hong Kong Drug Allergy Delabelling Initiative, a nurse-led, protocol-driven evaluation, was safe and effective in penicillin allergy delabeling. It led to an even higher rate of future penicillin use after delabeling and mitigated the need for unnecessary skin testing among LR patients.
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Hipersensibilidade a Drogas , Hipersensibilidade , Adulto , Humanos , Estudos Retrospectivos , Hong Kong/epidemiologia , Papel do Profissional de Enfermagem , Penicilinas/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , Testes Cutâneos , Antibacterianos/efeitos adversosRESUMO
Context: The trend of people using complementary and alternative medicine (CAM) has been increasing globally. To enact policies and regulations that promote the safe use of CAM, a detailed investigation is needed into people's knowledge, practices, and beliefs related to CAM. Food therapy has long been regarded as an important part of traditional Chinese medicine (TCM), a type of CAM. Objective: This study intended to empirically examine the public's knowledge about TCM food therapy, including the sources of that knowledge, actual practices, and the public's beliefs about the therapy. Design: The research team designed a questionnaire to test the public's understanding of food properties as designated in TCM food therapy and to identify the public's sources of knowledge and experience in using food therapy. Setting: The study took place at the College of Professional and Continuing Education, the Hong Kong Polytechnic University, and the University of Hong Kong in Hong Kong, China. Participants: Participants were 447 Chinese students participating in postsecondary or tertiary education at the two higher education institutions mentioned above. Outcome Measures: The survey's quantitative questions examined respondents' prior TCM knowledge, sources of knowledge, and food therapy experience compared to their ability to correctly categorize 24 foods. The survey's qualitative questions examined the general practice of food therapy and the cultural beliefs underlying the food therapy strategies that participants used. Results: The study showed that: (1) having prior and partial knowledge of food properties (P = .000); (2) seeking information from the internet (P = .000), television (P = .0473) and friends (P = .0181); and (3) having used food therapy for chronic conditions (P = .0034) significantly improved participants ability to correctly categorize foods as to their food therapy characteristics. Conclusions: Participants relied less on traditional medical sources such as parents and health professionals but more on the internet, which may have empowered them through wider access to information. The study has further contributed to the study of Complementary and Alternative Medicine (CAM) by highlighting the role of cultural practices and beliefs in TCM food therapy.
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Terapias Complementares , Medicina Tradicional Chinesa , Humanos , Hong Kong , China , Pessoal de SaúdeRESUMO
Replacement of missing teeth is becoming more prevalent, currently with more than 700,000 dental implants being placed every year. Patients seek out dental treatment with the expectations of having procedures performed in the least number of time/visits, for as inexpensive as possible, and at the highest quality. As this continues, clinicians can adapt with changing times and adopt the newer advancements in digital dentistry. This case letter aims to provide readers with insight to integration of digital workflows to optimize patient and clinician outcomes with single tooth implant therapy.
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OBJECTIVE: Patient-Reported Experience Measures (PREMs) provide valuable patient feedback on quality of care and have been associated with clinical outcomes. We aimed to test the reliability of a modified adult trauma care PREM instrument delivered to adolescents admitted to hospital for traumatic injuries, and their parents. Modifications included addition of questions reflecting teen-focused constructs on education supports, social network maintenance and family accommodation. RESULTS: Forty adolescent patients and 40 parents participated. Test-retest reliability was assessed using Cohen's kappa, weighted kappa, and percent agreement between responses. Directionality of changed responses was noted. Most of the study ran during the COVID-19 pandemic. We established good reliability of questions related to in-hospital and post-discharge communication, clinical and ancillary care and family accommodation. We identified poorer reliability among constructs reflecting experiences that varied from the norm during the pandemic, which included "maintenance of social networks", "education supports", "scheduling clinical follow-ups" and "post-discharge supports". Parents, but not patients, demonstrated more directionality of change of responses by responding with more negative in-hospital and more positive post-discharge experiences over time between the test and retest periods, suggesting risk of recall bias. Situational factors due to the COVID-19 pandemic and potential risks of recall bias may have limited the reliability of some parts of the survey.
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COVID-19 , Adolescente , Adulto , Assistência ao Convalescente , COVID-19/epidemiologia , Humanos , Pandemias , Alta do Paciente , Reprodutibilidade dos TestesRESUMO
Inorganic-organic hybrid materials represent a large share of newly reported structures, owing to their simple synthetic routes and customizable properties1. This proliferation has led to a characterization bottleneck: many hybrid materials are obligate microcrystals with low symmetry and severe radiation sensitivity, interfering with the standard techniques of single-crystal X-ray diffraction2,3 and electron microdiffraction4-11. Here we demonstrate small-molecule serial femtosecond X-ray crystallography (smSFX) for the determination of material crystal structures from microcrystals. We subjected microcrystalline suspensions to X-ray free-electron laser radiation12,13 and obtained thousands of randomly oriented diffraction patterns. We determined unit cells by aggregating spot-finding results into high-resolution powder diffractograms. After indexing the sparse serial patterns by a graph theory approach14, the resulting datasets can be solved and refined using standard tools for single-crystal diffraction data15-17. We describe the ab initio structure solutions of mithrene (AgSePh)18-20, thiorene (AgSPh) and tethrene (AgTePh), of which the latter two were previously unknown structures. In thiorene, we identify a geometric change in the silver-silver bonding network that is linked to its divergent optoelectronic properties20. We demonstrate that smSFX can be applied as a general technique for structure determination of beam-sensitive microcrystalline materials at near-ambient temperature and pressure.
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Elétrons , Prata , Cristalografia por Raios X , Lasers , Difração de Raios XRESUMO
Under the sudden outbreak of COVID-19 worldwide, students were forced to switch from face-to-face to online learning. This study reports the experience of Hong Kong students in higher education concerning the challenges they faced, the strategies they used and the support they needed in their online learning during the period. An online questionnaire was used to invite students to answer open-ended questions about these three aspects. 145 students from two higher education institutions completed the questionnaire and their comments were coded using thematic analysis. The study has discovered that socio-economic factors may have presented difficulties to students' online learning concerning their study environment and access to equipment. Students were emotionally distressed by online learning, particularly by the quality of feedback and clarity of course arrangement, so support for these aspects should be given. Self-regulated learning strategies were found to have been deployed by students to facilitate their learning, in which the use of time management apps and lecture videos highlights the increasing importance of technology to self study. These socio-economic, technological and emotional factors will be further discussed and corresponding suggestions will be made to help teachers and university policy makers examine the conditions that can help improve and promote online learning for higher education students under COVID-19.
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BACKGROUND AND OBJECTIVES: Canada legalized nonmedical cannabis possession and sale in October 2018. In the United States, state legalization has been tied to an increase in cannabis-related emergency department (ED) visits; however, little research exists on provincial changes in pediatric visits after nationwide legislation. We compared pre- and postlegalization trends in pediatric cannabis-related ED visits and presentation patterns in urban Alberta EDs. METHODS: Retrospective National Ambulatory Care Reporting System data were queried for urban Alberta cannabis-related ED visits among patients aged <18 years from October 1, 2013, to February 29, 2020. Population subgroups included children (aged 0-11 years), younger adolescents (12 to 14 years), and older adolescents (15 to 17 years). We calculated interrupted time series, incident rate ratios (IRRs), and relative risk (RR) ratios to identify trend change. IRRs identified changes against growth-adjusted Alberta population, while RRs measured presentation pattern changes against prelegalization ED visits. RESULTS: Pediatric visit volume did not change postlegalization when accounting for preexisting volume trends. Unintentional ingestions increased in children (IRR: 1.77, 95% confidence interval [CI]: 1.42 to 2.20 and RR: 1.24, 95% CI: 1.05 to 1.47, respectively) and older adolescents (IRR: 1.36, 95% CI: 1.07 to 1.71 and RR: 1.48, 95% CI: 1.21 to 1.81, respectively). Presentation patterns remained similar, although older adolescent co-ingestant use decreased (RR: 0.77, 95% CI: 0.67 to 0.88), whereas hyperemesis cases increased (RR: 1.64, 95% CI: 1.13 to 2.37). CONCLUSIONS: Cannabis legalization has increased child and older adolescent unintentional cannabis ingestions, increasing child cannabis-related ED visits. Changes highlight need for public health interventions targeting pediatric exposures.