bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential impact of oral flora dispersal on patients wearing face masks when undergoing ophthalmologic procedures
Authors: Angaramo Santiago , Law Janice C , Maris Alexander Spyros , Schmitz Jonathan Edward , Liu Yuhan , Chen Qingxia , Chomsky Amy
Published: October 2021

Objective

The purpose of this study is to investigate the amount of oral flora dispersion towards the ocular surface in relation to various face mask scenarios.

Methods and analysis

Thirty participants were recruited for this prospective cross-sectional study. Each participant was seated and instructed to hold a blood agar plate perpendicular to the bridge of their nose and facing downward. Participants then partook in three unique face mask scenarios: no face mask, surgical face mask and surgical face mask with tape securing the superior edge. During each scenario, participants were instructed to forcefully exhale for 5 s three times. The primary outcome measure was the number of colony-forming units (CFUs) grown on each face mask scenario-specific plate.

Results

Thirty participants were recruited for the study, and a total of 90 chocolate agar plates were successfully incubated. The proportion of detecting any CFU was 6.67% (95% CI: 0.818% to 22.1%) for no mask scenario, 0% (95% CI: 0% to 11.6%) for mask scenario and 3.33% (95% CI: 0.0844% to 17.2%) for mask-taped scenario. The mean differences in proportion of detecting any CFU were 3.33% (95% CI: 0% to 10%, p=0.309) for no mask versus mask taped, 3.35% (95% CI: 0% to 10%, p=0.307) for mask taped versus mask and 6.68% (95% CI: 0% to 16.7%, p=0.142) for no mask versus mask.

Conclusion

This study showed no difference in bacterial dispersion towards the ocular surface when comparing no face mask, a surgical face mask without tape or a surgical face mask with tape.
Concordance with urgent referral guidelines in patients presenting with any of six ‘alarm’ features of possible cancer: a retrospective cohort study using linked primary care records
Authors: Wiering Bianca , Lyratzopoulos Georgios , Hamilton Willie , Campbell John , Abel Gary
Published: October 2021

Background

Clinical guidelines advise GPs in England which patients warrant an urgent referral for suspected cancer. This study assessed how often GPs follow the guidelines, whether certain patients are less likely to be referred, and how many patients were diagnosed with cancer within 1 year of non-referral.

Methods

We used linked primary care (Clinical Practice Research Datalink), secondary care (Hospital Episode Statistics) and cancer registration data. Patients presenting with haematuria, breast lump, dysphagia, iron-deficiency anaemia, post-menopausal or rectal bleeding for the first time during 2014–2015 were included (for ages where guidelines recommend urgent referral). Logistic regression was used to investigate whether receiving a referral was associated with feature type and patient characteristics. Cancer incidence (based on recorded diagnoses in cancer registry data within 1 year of presentation) was compared between those receiving and those not receiving referrals.

Results

48 715 patients were included, of which 40% (n=19 670) received an urgent referral within 14 days of presentation, varying by feature from 17% (dysphagia) to 68% (breast lump). Young patients (18–24 vs 55–64 years; adjusted OR 0.20, 95% CI 0.10 to 0.42, p<0.001) and those with comorbidities (4 vs 0 comorbidities; adjusted OR 0.87, 95% CI 0.80 to 0.94, p<0.001) were less likely to receive a referral. Associations between patient characteristics and referrals differed across features: among patients presenting with anaemia, breast lump or haematuria, those with multi-morbidity, and additionally for breast lump, more deprived patients were less likely to receive a referral. Of 29 045 patients not receiving a referral, 3.6% (1047) were diagnosed with cancer within 1 year, ranging from 2.8% for rectal bleeding to 9.5% for anaemia.

Conclusions

Guideline recommendations for action are not followed for the majority of patients presenting with common possible cancer features. A significant number of these patients developed cancer within 1 year of their consultation, indicating scope for improvement in the diagnostic process.
Association between anticoagulants and mortality and functional outcomes in older patients with major trauma
Authors: Sato Nobuhiro , Cameron Peter , Mclellan Susan , Beck Ben , Gabbe Belinda
Published: October 2021

Background

The number of trauma patients taking anticoagulants and antiplatelet agents is increasing as society ages. However, there have been limited and inconsistent reports of the association between anticoagulants and mortality and functional outcomes. This study aimed to quantify the association between anticoagulant/antiplatelet medication at the time of injury and both short-term and longer-term outcomes in older major trauma patients.

Methods

This was a population-based registry study using data from the Victorian State Trauma Registry from July 2017 to June 2018. We included patients with major trauma aged 65 years and older. The outcomes of interest were in-hospital mortality, hospital length of stay, intensive care unit length of stay and the Extended Glasgow Outcome Scale (GOS-E) at 6 months after injury. We examined the association between the outcomes and anticoagulants/antiplatelet agents at the time of injury and used multivariable logistic regression models to account for known confounders.

Results

There were 1323 older adults eligible for inclusion in the study, of which 249 (18.8%) were taking anticoagulants (n=8 were taking both anticoagulants and antiplatelet agents), 380 (28.7%) were taking antiplatelet agents and 694 (52.5%) were not using either. Any anticoagulant use was associated with higher odds of in-hospital mortality (adjusted OR (AOR), 2.38; 95% CI 1.58 to 3.59) compared with not using anticoagulants. No differences were observed in the GOS-E at 6 months after injury between any anticoagulants use, antiplatelet use and no anticoagulant use (anticoagulant AOR, 0.71; 95% CI 0.48 to 1.05, antiplatelet AOR, 1.02; 95% CI 0.73 to 1.42).

Conclusion

Anticoagulant use at the time of injury was associated with higher odds of in-hospital mortality but did not adversely impact functional outcomes at 6 months after injury. These findings demonstrate the importance of seeking an accurate history of anticoagulant use and its indication, as well as the immediate initiation of reversal therapies.
Integrated emergency care reduces hospital admissions and reduces in hospital mortality
Authors: Boyle Adrian
Published: October 2021

Introduction

We closed our Medical Admissions Unit and relocated the staff into an enlarged Emergency Department. We streamlined our assessment processes to reduce duplication of effort. We aimed to evaluate the effect of this on mortality, admission ratios and quality of care.

Methods

We evaluated the effectiveness of this approach using multiple routinely collected measures. We studied the 3 years before the change and 3 years afterward in our centre. We obtained an independent analysis of our standardised admission ratios by the Dr Foster unit. We evaluated mortality with Dr Foster data. We evaluated quality of care by comparing the numbers of complaints, incident forms and re-admissions.

Results

There was a decline in the standardised admissions ratios from 105.8 (95% CI 104.9 to 106.6) in 2003 to 89.5 (95% CI 88.8 to 90.2) in 2009. Hospital Mortality for non-elective admissions also fell slightly. All measures of quality improved or were unchanged after the change.

Discussion

Integrating Emergency Care in one place is associated with substantial reductions in admissions. This system is associated with a slight reduction in mortality and improved quality of care measures.
An investigation into the cognitive and neuropsychological sequelae of minor head injury in children – a prospective pilot study
Authors: Kerr Jacques
Published: October 2021

Objectives

Although the majority of head-injured children are Glasgow Coma Scale (GCS) 15 and do not require admission or further investigations there is evidence that some children with a minor head injury (MHI) will go on to experience significant morphological and functional brain deficits. In view of the lack of controlled studies into the sequelae of MHI in children we carried out a pilot study that examined the neuropsychological performance in children who had sustained an MHI.

Methods

Children aged 6–12 years who presented to the Emergency Department of the Royal Hospital for Sick Children in Edinburgh with a MHI (GCS 15) were recruited to the study. Neuropsychological assessment was performed using the Cambridge Neuropsychological Test Automated Battery (CANTAB); a computerised battery of tests, which measures motor skills, visual attention, spatial memory, working memory and non-verbal memory span. CANTAB also assesses executive function, which is the highest level of cognitive function that manages planning and allows flexible thought and action.

Results

15 head-injured children were recruited over the study period (eleven boys and four girls). A 2 (subject groups) × 3 (time points) repeated measures Analysis of variance was used on the number of problems solved using the minimum number of computer moves at each time point, which showed a significant interaction (p=0.003). Bonferroni posthoc comparisons demonstrated that in week 1 the head-injured group were significantly lower in performance compared to normative data (p=0.03), but significantly increased in performance between week 1 and 12 months (p=0.0001). The difference in the head-injured group performance between week 1 and week 6 approached significance (p=0.05).

Conclusion

The MHI group show a significantly poorer performance with regards to problem-solving in a minimum number of moves, which may indicate impulsive tendencies and insufficient planning ability. Children with a MHI may therefore be at risk of developing problems with high-level cognitive function postinjury.
Economic analysis of the randomised assessment of treatment using panel assay of cardiac markers trial
Authors: Goodacre Steve
Published: October 2021

Background

The randomised Assessment of Treatment using Panel Assay of Cardiac markers (RATPAC) trial showed that diagnostic assessment with a point-of-care biomarker panel increased successful discharges among patients presenting to hospital with acute chest pain. We aimed to determine whether point-of-care panel assessment reduced healthcare costs and whether it was likely to be cost-effective.

Methods

Economic analysis was undertaken using individual patient resource use data from the RATPAC trial (n=2263) and health utility measured on the EQ-5D at one and 3 months. Resource use was valued using national unit costs. Quality-adjusted life years (QALYs) were calculated from EQ-5D scores using the trapezium rule. Mean costs and QALYs accrued after point-of-care and standard care were compared and cost-effectiveness estimated in terms of probability of dominance and incremental cost per QALY.

Results

Point-of-care panel assessment was associated with higher emergency department costs, coronary care costs and cardiac intervention costs, but lower general inpatient costs. Mean costs per patient were £1217 with point-of-care versus £1006 with standard care (p=0.047), while mean QALYs were 0.158 versus 0.161 (p=0.250). The probability of standard care being dominant (ie, cheaper and more effective) was 0.888, while the probability of the point-of-care panel being dominant was 0.004. These probabilities were not markedly altered by sensitivity analysis varying the costs of the point-of-care panel and excluding intensive care costs.

Conclusion

Point-of-care panel assessment does not reduce costs despite reducing admissions and may even increase costs. It is unlikely to be considered a cost-effective use of national healthcare resources.
Temperature post out-of-hospital cardiac arrest: the TOPCAT study
Authors: Lyon Richard
Published: October 2021

Introduction

Out-of-hospital cardiac arrest (OHCA) is a significant cause of death and severe neurological disability. The only postreturn of spontaneous circulation (ROSC) therapy shown to increase survival is mild therapeutic hypothermia (MTH). The relationship between body temperature post OHCA and outcome is still poorly defined.

Methods

Prospective observational study of all OHCA patients admitted to a single centre for a 14-month period. Oesophageal temperature was measured in the Emergency Department and Intensive Care Unit (ICU). Select patients had prehospital temperature monitoring.

Results

164 OHCA patients were included in the study. 105 (64.0%) were pronounced dead in the Emergency Department. 59 (36.0%) were admitted to ICU for cooling; 40 (24.4%) died in ICU and 19 (11.6%) survived to hospital discharge. Patients who achieved ROSC and had oesophageal temperature measured prehospital (n=29) had a mean prehospital temperature of 33.9°C (95% CI 33.2 to 34.5). All patients arriving in the ED post OHCA had a relatively low oesophageal temperature (34.3°C, 95% CI 34.1 to 34.6). Patients surviving to hospital discharge were warmer on admission to ICU than patients who died in hospital (35.7°C vs 34.3°C, p<0.05). Patients surviving to hospital discharge also took longer to reach target MTH temperature than non-survivors (2 h 48 min vs 1 h 32 min, p<0.05). There was no difference in mean arterial blood pressure on arrival in the ED between survivors and non-survivors.

Conclusions

Following OHCA all patients have oesophageal temperatures below normal in the prehospital phase and on arrival in the Emergency Department. This questions the need for prehospital cooling post-OHCA patients. Patients who achieve ROSC following OHCA and survive to hospital discharge are warmer on arrival in ICU and take longer to reach target MTH temperatures compared to patients who die in hospital. The mechanisms of action underlying oesophageal temperature and survival from OHCA remain unclear and further research is warranted to clarify this relationship.
Current practice and opinion regarding the use of therapeutic hypothermia after cardiac arrest survival in children: a survey of UK Paediatric Emergency Medicine consultants to inform the cold-PACK study
Authors: Lyttle M
Published: October 2021

Background and aims

Therapeutic hypothermia improves neurological outcome in adults after cardiac arrest and term neonates with hypoxic ischaemic encephalopathy. There is currently no evidence to support its use in the paediatric population following cardiac arrest. This survey of UK Paediatric Emergency Medicine (PEM) consultants aims to ascertain current practice in UK, and attitudes and opinions to guide the feasability of a multicentre randomised controlled trial (RCT) of therapeutic hypothermia after cardiac arrest in children (the Cold-PACK study).

Methods

In early 2010 UK PEM consultants were invited to complete a web based survey of current practice in therapeutic hypothermia and opinions regarding future research.

Results

Following return of spontaneous circulation after cardiac arrest in children 58 % of respondents never cool, 35.5% seldom cool and 3.2 % often cool. The most common reasons for not cooling are ‘not enough research evidence to support its use’ (31.8%) and ‘no equipment available to initiate cooling’ (31.8%). 87.1% of responders did not know if therapeutic hypothermia improved outcome. Only 12.9% have a specific protocol for cooling, and there is wide variation in practice with respect to the depth of cooling. In those who cool, a range of cooling methods is employed, the most common of which is ice packs applied to skin (22.6%). 86% of respondents would support an RCT in the UK investigating the use of hypothermia after cardiac arrest, and 87% of respondents would be willing to commence therapeutic hypothermia in the Emergency Department. 80% felt that deferred consent could be used.

Conclusions

There is wide variation in UK practice in the use of therapeutic hypothermia in PEM. This survey demonstrates clinical equipoise, and shows support for a future RCT of therapeutic hypothermia after cardiac arrest in children.
A lean, keen, kid-centred machine: change in children's ED
Authors: Crew Jamie
Published: October 2021

Introduction

Our Children's Emergency Department, as part of a whole hospital improvement project has been piloting ‘Lean Thinking’ to develop and trial new ideas and processes within the department. Our initial project has been focusing on how we manage injuries in the department with the aim of ‘developing a system whereby children with injuries can be seen more efficiently and effectively by having combined medical and nursing staff assessment and treatment, coupled with the ability to prescribe and make appointments during the same consultation.’

Methods

We have used a series of lean processes and tools (Scope tools, KANO workshops, current state, process mapping, future state, ideas wall, Plan-Do-Study-Act (PDSA) cycle) to engage staff and facilitate them to generate ideas and develop projects for change and improvement. The initial priority for our Children's Emergency Department was the development of a multidisciplinary area in which to see and treat injuries. The idea was then developed into a clinical process and trialled, within the department, in real-time without any cessation of service. The findings are analysed, the processes refined, and further trials instituted to consolidate the process before full implementation.

Results

We have completed three trials of the MDT injuries area with dramatic improvements in patient and staff satisfaction, as well as more objective outcomes one example being decreased patient journey. The average time from arrival to discharge in the trial was compared with baseline data for the same time over the preceeding 10 weeks:- Trial 1 (4 h) baseline 120 min, trial 30 min; Trial 2 (8 h) baseline 103 min, trial 54; Trial 3 (10 h) baseline 94 min, trial 49. We are now moving to implementation of this new area for 10 h a day, 7 days a week.

Conclusion

Lean processes with real-time trials can facilitate successful, continuous, staff driven change within a Paediatric Emergency Department.
The Q**** Study – basic randomised evaluation of attendance at a children's emergency department
Authors: Johnson Graham
Published: October 2021

Introduction

Health Professionals are superstitious; be it a little ritual before sitting a cannula, or wearing a particular item of clothing while on-call, there are many things that we irrationally do day-to-day. One of the most well known superstitions is that uttering the word “quiet” (Q****) will immediately turn what has previously been a pleasant day into an extremely busy one. This belief is strongly at odds with modern Evidence Based Medicine, in fact a thorough literature review revealed no published research in this area. The aim of this study was to establish if there was any evidence that saying the word “Q****” influenced the number of attendances to a Children's Emergency Department.

Method

We measured attendance during three time periods per day for the study duration (A – 00:00 to 07:59; B – 08:00 to 15:59; C – 16:00 to 23:59). At the beginning of each time period a randomised envelope was opened that contained either the word “Q****”, “Busy” or was blank, this prompted the doctor and nurse in charge to utter a sentence containing the word from the envelope, which was also displayed for the rest of the 8 h.

Results

1454 patients were included in the intervention period and 2818 were included in the 4 week control period to measure typical attendance. Mean attendance for intervention and control were: A 7.29 and 7.71; B 40.86 and 40; C 55.57 and 52.86 respectively. “Q****” and Busy were uttered 12 times each. There was no statistically significant difference in attendance for either word.

Conclusion

This study has shown that the long-held belief that saying the word ‘Quiet’ has dire consequences is unfounded. We would recommend further research to explore whether other words could be used to influence Emergency Department attendances.
Multicentre comparative analysis of long-term outcomes after aortic valve replacement in children
Authors: Knight Jessica H , Sarvestani Amber Leila , Ibezim Chizitam , Turk Elizabeth , McCracken Courtney E , Alsoufi Bahaaldin , St Louis James , Moller James H , Raghuveer Geetha , Kochilas Lazaros K
Published: October 2021

Objective

The ideal valve substitute for surgical intervention of congenital aortic valve disease in children remains unclear. Data on outcomes beyond 10–15 years after valve replacement are limited but important for evaluating substitute longevity. We aimed to describe up to 25-year death/cardiac transplant by type of valve substitute and assess the potential impact of treatment centre. Our hypothesis was that patients with pulmonic valve autograft would have better survival than mechanical prosthetic.

Methods

This is a retrospective cohort study from the Pediatric Cardiac Care Consortium, a multi-institutional US-based registry of paediatric cardiac interventions, linked with the National Death Index and United Network for Organ Sharing through 2019. Children (0–20 years old) receiving aortic valve replacement (AVR) from 1982 to 2003 were identified. Kaplan-Meier transplant-free survival was calculated, and Cox proportional hazard models estimated hazard ratios for mechanical AVR (M-AVR) versus pulmonic valve autograft.

Results

Among 911 children, the median age at AVR was 13.4 years (IQR=8.4–16.5) and 73% were male. There were 10 cardiac transplants and 153 deaths, 5 after transplant. The 25-year transplant-free survival post AVR was 87.1% for autograft vs 76.2% for M-AVR and 72.0% for tissue (bioprosthetic or homograft). After adjustment, M-AVR remained related to increased mortality/transplant versus autograft (HR=1.9, 95% CI=1.1 to 3.4). Surprisingly, survival for patients with M-AVR, but not autograft, was lower for those treated in centres with higher in-hospital mortality.

Conclusion

Pulmonic valve autograft provides the best long-term outcomes for children with aortic valve disease, but AVR results may depend on a centre’s experience or patient selection.
Severity of anaemia and association with all-cause mortality in patients with medically managed left-sided endocarditis
Authors: Pries-Heje Mia Marie , Hasselbalch Rasmus Bo , Wiingaard Christoffer , Fosbøl Emil Loldrup , Glenthøj Andreas Birkedal , Ihlemann Nikolaj , Gill Sabine Ute Alice , Christiansen Ulrik , Elming Hanne , Bruun Niels Eske , Povlsen Jonas Agerlund , Helweg-Larsen Jannik , Schultz Martin , Østergaard Lauge , Fursted Kurt , Christensen Jens Jørgen , Rosenvinge Flemming , Køber Lars , Tønder Niels , Moser Claus , Iversen Kasper , Bundgaard Henning
Published: October 2021

Objective

To assess the prevalence and severity of anaemia in patients with left-sided infective endocarditis (IE) and association with mortality.

Methods

In the Partial Oral versus Intravenous Antibiotic Treatment of Endocarditis trial, 400 patients with IE were randomised to conventional or partial oral antibiotic treatment after stabilisation of infection, showing non-inferiority. Haemoglobin (Hgb) levels were measured at randomisation. Primary outcomes were all-cause mortality after 6 months and 3 years. Patients who underwent valve surgery were excluded due to competing reasons for anaemia.

Results

Out of 400 patients with IE, 248 (mean age 70.6 years (SD 11.1), 62 women (25.0%)) were medically managed; 37 (14.9%) patients had no anaemia, 139 (56.1%) had mild anaemia (Hgb <8.1 mmol/L in men and Hgb <7.5 mmol/L in women and Hgb ≥6.2 mmol/L) and 72 (29.0%) had moderate to severe anaemia (Hgb <6.2 mmol/L). Mortality rates in patients with no anaemia, mild anaemia and moderate to severe anaemia were 2.7%, 3.6% and 15.3% at 6-month follow-up and 13.5%, 20.1% and 34.7% at 3-year follow-up, respectively. Moderate to severe anaemia was associated with higher mortality after 6 months (HR 4.81, 95% CI 1.78 to 13.0, p=0.002) and after 3 years (HR 2.14, 95% CI 1.27 to 3.60, p=0.004) and remained significant after multivariable adjustment.

Conclusion

Moderate to severe anaemia was present in 29% of patients with medically treated IE after stabilisation of infection and was independently associated with higher mortality within the following 3 years. Further investigations are warranted to determine whether intensified treatment of anaemia in patients with IE might improve outcome.
Prediction of incident atrial fibrillation in community-based electronic health records: a systematic review with meta-analysis
Authors: Nadarajah Ramesh , Alsaeed Eman , Hurdus Ben , Aktaa Suleman , Hogg David , Bates Matthew G D , Cowan Campbel , Wu Jianhua , Gale Chris P
Published: October 2021

Objective

Atrial fibrillation (AF) is common and is associated with an increased risk of stroke. We aimed to systematically review and meta-analyse multivariable prediction models derived and/or validated in electronic health records (EHRs) and/or administrative claims databases for the prediction of incident AF in the community.

Methods

Ovid Medline and Ovid Embase were searched for records from inception to 23 March 2021. Measures of discrimination were extracted and pooled by Bayesian meta-analysis, with heterogeneity assessed through a 95% prediction interval (PI). Risk of bias was assessed using Prediction model Risk Of Bias ASsessment Tool and certainty in effect estimates by Grading of Recommendations, Assessment, Development and Evaluation.

Results

Eleven studies met inclusion criteria, describing nine prediction models, with four eligible for meta-analysis including 9 289 959 patients. The CHADS (Congestive heart failure, Hypertension, Age>75, Diabetes mellitus, prior Stroke or transient ischemic attack) (summary c-statistic 0.674; 95% CI 0.610 to 0.732; 95% PI 0.526–0.815), CHA2DS2-VASc (Congestive heart failure, Hypertension, Age>75 (2 points), Stroke/transient ischemic attack/thromboembolism (2 points), Vascular disease, Age 65–74, Sex category) (summary c-statistic 0.679; 95% CI 0.620 to 0.736; 95% PI 0.531–0.811) and HATCH (Hypertension, Age, stroke or Transient ischemic attack, Chronic obstructive pulmonary disease, Heart failure) (summary c-statistic 0.669; 95% CI 0.600 to 0.732; 95% PI 0.513–0.803) models resulted in a c-statistic with a statistically significant 95% PI and moderate discriminative performance. No model met eligibility for inclusion in meta-analysis if studies at high risk of bias were excluded and certainty of effect estimates was ‘low’. Models derived by machine learning demonstrated strong discriminative performance, but lacked rigorous external validation.

Conclusions

Models externally validated for prediction of incident AF in community-based EHR demonstrate moderate predictive ability and high risk of bias. Novel methods may provide stronger discriminative performance.

Systematic review registration

PROSPERO CRD42021245093.
Living in a block group with a higher eviction rate is associated with increased odds of preterm delivery
Authors: Freedman Alexa A , Smart Britney P , Keenan-Devlin Lauren S , Borders Ann , Ernst Linda M , Miller Gregory E
Published: October 2021

Background

Housing instability is associated with adverse pregnancy outcomes. Recent studies indicate that eviction, which may affect a larger segment of the population than other forms of housing instability, is also associated with adverse pregnancy outcomes. However, these studies evaluate eviction across large areas, such as counties, so it remains unclear whether these patterns extend to individual-level pregnancy outcomes.

Methods

We used data on a cohort of all singleton live births at a single Chicago hospital between March 2008 and March 2018 to investigate the associations between block-group eviction rates and individual adverse pregnancy outcomes. Eviction data were obtained from the Eviction Lab at Princeton University. Generalised estimating equations were used to estimate associations and account for correlations among individuals living in the same block groups.

Results

Individuals living in block groups in the highest quartile for eviction filing rate were 1.17 times as likely to deliver preterm (95% CI: 1.08 to 1.27) and 1.13 times as likely to deliver a small for gestational age infant (95% CI: 1.03 to 1.25) as compared with individuals living in block groups in the lowest quartile. Further, tests for linear trend indicated that for each quartile increase in eviction filing rate, there was a corresponding increase in odds of adverse outcomes (p<0.05). Results were strongest in magnitude for those with low neighbourhood and individual socioeconomic status, who are most likely to be renters and affected by local eviction policies.

Conclusion

Our results suggest that individuals living in block groups with higher eviction rates are more likely to deliver preterm. Future research should explore associations of individual experience with eviction on adverse pregnancy outcomes and examine whether policies to improve tenant protections also impact pregnancy outcomes.
ANA-positive primary immune thrombocytopaenia: a different clinical entity with increased risk of connective tissue diseases
Authors: Liu Yuan , Chen Shiju , Yang Guomei , Wang Bin , Lan Jinying , Dai Fan , Rao Peishi , Wu Puqi , Qian Hongyan , Shi Guixiu
Published: October 2021

Objective

Primary immune thrombocytopaenia (ITP) is highly heterogeneous. ANA-positive primary ITP may resemble the preclinical stage of connective tissue diseases (CTDs), but is still considered primary ITP due to a controversial CTD risk assessment in this group. The objective of this study was to clarify the risk of CTD in ANA-positive patients with primary ITP.

Methods

We performed a retrospective cohort study and a meta-analysis. 586 patients with newly diagnosed primary ITP were followed up and Cox regression analyses were used to analyse the associations of ANA positivity and other immune parameters with CTD development.

Results

The mean follow-up time was 37 (19–56) months. ANA was positive in 21.33% (125 of 586) of patients with primary ITP in our retrospective cohort, and the overall rate of ANA positivity in the meta-analysis was 17.06% (369 of 2163). The adjusted HR for CTD in ANA-positive primary ITP was 6.15 (95% CI 2.66 to 14.23, p<0.001). Five patients in the ANA-positive group developed SLE (5 of 125, 4.0%), significantly higher than in the ANA-negative group (0 of 461, 0%). A clinical model combining ANA, anti-Sjogren’s syndrome A antibody and C3 was successfully developed to predict the risk of CTD in patients with primary ITP. Increased risk of CTD (risk ratio=12.43, 95% CI 7.91 to 19.55, p<0.00001), especially SLE (risk ratio=30.41, 95% CI 13.23 to 69.86, p<0.00001), among ANA-positive patients with primary ITP was confirmed by a meta-analysis of previous studies and the present study.

Conclusions

The findings suggest that ANA-positive primary ITP is a clinical entity distinct from other primary ITPs and is associated with increased risk of developing CTDs, especially SLE.
Flavour capsule cigarette use and perceptions: a systematic review
Authors: Kyriakos Christina N , Zatoński Mateusz Zygmunt , Filippidis Filippos T
Published: October 2021

Objective

This systematic review on flavour capsule cigarettes aims to examine prevalence, correlates of use, behaviours and perceptions of these products globally.

Data sources

A search of original, peer-reviewed research without restrictions in publication year, population, study design or language, using a combination of cigarette and capsule terms was conducted across four databases (Medline, Embase, Web of Science and Scopus), indexed until 30 April 2021.

Study selection

Studies were included if they presented original, human subjects research on flavour capsule cigarettes.

Data extraction

Two authors independently extracted data on main outcome results and assessed risk of bias using a validated quality assessment tool (QATSDD).

Data synthesis

Of 842 unduplicated database records and four studies from citation searching screened, 20 studies were included in the review. Studies reported data from 2009 to 2019 across eight countries, the majority of which used cross-sectional or focus group study designs. Current capsule use among smokers was highest in Chile and Mexico (40%) and was associated with younger age, and in some countries, with being female. Capsule cigarettes are perceived as tasting better, being smoother on the throat, more fun to smoke, and more attractive compared with non-capsule cigarettes, particularly among susceptible non-smokers and non-daily smokers.

Conclusion

Findings call for the adoption of comprehensive tobacco control policies that account for flavour capsules and similar iterations, which can increase appeal through flavours and innovative features. Continued monitoring and research of these products is critical, with particular attention to low-income and middle-income countries, which make up a disproportionately larger share of the capsule market.
Thermodynamic properties of Bardeen black holes in dRGT massive gravity
Authors: Singh R.P. , Singh B.K. , Gupta B.R.K. , Sachan Shobhit
Published: October 2021

The Bardeen black hole solution is the first spherically symmetric regular black hole based on the Sakharov and Gliner proposal which is a modification of the Schwarzschild black hole. We present the Bardeen black hole solution in the presence of the de Rham, Gabadaadze, and Tolly (dRGT) massive gravity, which is regular everywhere in the presence of a nonlinear source. The obtained solution reduces to the Bardeen black hole in the absence of a massive gravity parameter, and the Schwarzschild black hole when magnetic charge g = 0. We investigated the thermodynamic quantities, that is, mass (M), temperature (T), entropy (S), and free energy (F), in terms of the horizon radius for both canonical and grand canonical ensembles. We checked the local and global stability of the obtained solution by studying the heat capacity and free energy. The heat capacity changes sign at r = rc. The black hole is thermodynamically stable with a positive heat capacity C > 0 (i.e., globally preferred with negative free energy F < 0). In addition, we studied the phase structure of the obtained solution in both ensembles.
Dark matter self-interactions from spin-2 mediators
Authors: Kang Yoo-Jin , Lee Hyun Min
Published: October 2021

We propose a new mechanism for rendering dark matter self-interacting in the presence of a massive spin-2 mediator. The derived Yukawa-type potential for dark matter is independent of the spins of dark matter in the leading order of the momentum expansion, so are the resulting non-perturbative effects for the dark matter self-scattering. We find that both the Born cross section and relatively mild resonance effects assist to make the self-scattering cross section velocity-dependent. We discuss how to evade the current indirect bounds on dark matter annihilations and show that the model is marginally compatible with perturbative unitarity in the ghost-free realization of the massive spin-2 particle.
Scalarized Einstein–Maxwell-scalar black holes in anti-de Sitter spacetime
Authors: Guo Guangzhou , Wang Peng , Wu Houwen , Yang Haitang
Published: October 2021

In this paper, we study spontaneous scalarization of asymptotically anti-de Sitter charged black holes in an Einstein–Maxwell-scalar model with a non-minimal coupling between the scalar and Maxwell fields. In this model, Reissner–Nordström-AdS (RNAdS) black holes are scalar-free black hole solutions, and may induce scalarized black holes due to the presence of a tachyonic instability of the scalar field near the event horizon. For RNAdS and scalarized black hole solutions, we investigate the domain of existence, perturbative stability against spherical perturbations and phase structure. In a micro-canonical ensemble, scalarized solutions are always thermodynamically preferred over RNAdS black holes. However, the system has much richer phase structure and phase transitions in a canonical ensemble. In particular, we report a RNAdS BH/scalarized BH/RNAdS BH reentrant phase transition, which is composed of a zeroth-order phase transition and a second-order one.
Covariant density and velocity perturbations of the quasi-Newtonian cosmological model in f(T) gravity
Authors: Sami Heba , Sahlu Shambel , Abebe Amare , Dunsby Peter K. S.
Published: October 2021

We investigate classes of shear-free cosmological dust models with irrotational fluid flows within the framework off(T) gravity. In particular, we use the$$1 + 3$$1+3covariant formalism and present the covariant linearised evolution and constraint equations describing such models. We then derive the integrability conditions describing a consistent evolution of the linearised field equations of thesequasi-Newtonianuniverses in thef(T) gravitational theory. Finally, we derive the evolution equations for the density and velocity perturbations of the quasi-Newtonian universe. We explore the behaviour of the matter density contrast for two models –$$f(T)= \mu T_{0}(T/T_{0})^{n}$$f(T)=μT0(T/T0)nand the more generalised case, where$$f(T)= T+ \mu T_{0} (T/T_{0})^{n}$$f(T)=T+μT0(T/T0)n, with and without the application of the quasi-static approximation. Our numerical solutions show that thesef(T) theories can be suitable alternatives to study the background dynamics, whereas the growth of energy density fluctuations change dramatically from the expected$$\Lambda $$ΛCDM behaviour even for small deviation from the general relativistic limits of the underlyingf(T) theory. Moreover, applying the so-called quasi-static approximation yields exact-solution results that are orders of magnitude different from the numerically integrated solutions of the full system, suggesting that these approximations are not applicable here.
Thermodynamics of graviton condensate
Authors: Alfaro Jorge , Mancilla Robinson
Published: October 2021

In this work, we present the thermodynamic study of a model that considers the black hole as a condensate of gravitons. In this model, the spacetime is not asymptotically flat because of a topological defect that introduces an angle deficit in the spacetime like in Global Monopole solutions. We have obtained a correction to the Hawking temperature plus a negative pressure associated with the black hole of mass M. In this way, the graviton condensate, which is assumed to be at the critical point defined by the condition $$\mu _{ch}=0,$$

μ

ch

=
0
,

has well-defined thermodynamic quantities P, V, $$T_{h}$$

T
h

, S, and U as any other Bose–Einstein condensate (BEC). In addition, we present a formal equivalence between the Letelier spacetime and the line element that describes the graviton condensate. We also discuss the Kiselev black hole, which can parametrize the most well-known spherically symmetric black holes. Finally, we present a new metric, which we will call the BEC–Kiselev solution, that allows us to extend the graviton condensate to the case of solutions with different matter contents.
Probing the parameters of a Schwarzschild black hole surrounded by quintessence and cloud of strings through four standard astrophysical tests
Authors: Cárdenas Víctor H. , Fathi Mohsen , Olivares Marco , Villanueva J. R.
Published: October 2021

In this paper, we concern about applying general relativistic tests on the spacetime produced by a static black hole associated with cloud of strings, in a universe filled with quintessence. The four tests we apply are precession of the perihelion in the planetary orbits, gravitational redshift, deflection of light, and the Shapiro time delay. Through this process, we constrain the spacetime’s parameters in the context of the observational data, which results in about $$\sim 10^{-9}$$

∼

10

-
9

for the cloud of strings parameter, and $$\sim 10^{-20}$$

∼

10

-
20

 m$$^{-1}$$

-
1

for that of quintessence. The response of the black hole to the gravitational perturbations is also discussed.
Rotating spacetimes generalizing Lifshitz black holes
Authors: Herrera-Aguilar Alfredo , Herrera-Mendoza Jhony A. , Higuita-Borja Daniel F.
Published: October 2021

We present a spinning black hole solution in d dimensions with a maximal number of rotation parameters in the context of the Einstein–Maxwell-Dilaton theory. An interesting feature of such a solution is that it accommodates Lifshitz black holes when the rotation parameters are set to zero. We verify the rotating nature of the black hole solution by performing the quasi-local analysis of conserved charges and defining the corresponding angular momenta. In addition, we perform the thermodynamical analysis of the black hole configuration, show that the first law of thermodynamics is completely consistent, and obtain a Smarr-like formula. We further study the thermodynamic stability of the constructed solution from a local viewpoint, by computing the associated specific heats, and from a global perspective, by using the so-called new thermodynamic geometry. We finally make some comments related to a pathology found in the causal structure of the obtained rotating black hole spacetime and compute some of its curvature invariants.
Fracture behaviors at inclusions of very-high-cycle fatigue in newly developed clean bearing steel
Authors: Suh Min-Soo , Nahm Seung-Hoon , Suh Chang-Min , Lee Seul-Bi
Published: October 2021

Bearing steel is essential for the driving parts of the rotating body, but fisheye crack of inclusions such as TiN, Al2O3 and Cr matrix is formed in the very-high-cycle fatigue (VHCF) regime. Therefore, research on the development of a clean bearing steel that reduces the size of inclusion such as TiN or that does not contain inclusion has been made recently. In this study, the results of long-term attempts by the maker to improve the performance and quality of bearing steel for very long life were quantitatively analyzed from the viewpoint of fracture mechanics. In other words, the phase transformation properties, VHCF characteristics with ultrasonic nanocrystal surface modification (UNSM) treatment and fracture mechanics analysis of this clean bearing are compared quantitatively with those of other common bearing steels from the viewpoint of engineering and industrial applications. The quenching and tempering (QT) specimens of the clean bearing showed fisheye cracks and duplex [Formula: see text]–[Formula: see text] curves in the VHCF regime. The fisheye crack of the clean bearing steel was an internal fatigue crack caused by a small inclusion mainly composed of Al2O3 in the VHCF region. However, fisheye cracking due to TiN and Cr matrix, which was observed in other common bearing steels, did not occur in the clean bearing steel due to the efforts of the developers of new clean bearing.
Solitary waves in magnetostrictive circular rods with temperature effect
Authors: Jia H. T. , Xue Chun-Xia , Chen Q.
Published: October 2021

A simple nonlinear model is constructed in this paper to study the solitary wave in an infinite circular magnetostrictive rod. Based on the constitutive relations for transversely isotropic magnetostrictive materials, considering the coupling of multiphysics, combined with Hamilton’s principle and Euler equation, the longitudinal wave equation (LWE) of the infinite circular rod is obtained. The nonlinearity considered is geometrically associated with the nonlinear normal strain in the longitudinal rod direction. The transverse Poisson’s effect is included by introducing the effective Poisson’s ratio. Solitary wave solution, non-topological bell-type soliton and singular periodic solutions of the LWE are obtained by the [Formula: see text]-expansion method. By using the reductive perturbation method, we derive the KdV equation, furthermore, the two-solitary solution is obtained. Numerical analysis results show that the increase of the magnetic field intensity or temperature will reduce the solitary wave’s propagation velocity. As the wave velocity ratio increases, the wave amplitude gradually increases; when the coupled physics parameter and the wave velocity ratio are constant, the increase of the dispersion parameter will make the wavelength longer. The dynamic behavior of the two-soliton solution in the magnetostrictive rod exhibits nonlinear superposition and has elastic collision characteristics.
Tnvmalloc: A Thread-Level-Based Wear-Aware Allocator for Nonvolatile Main Memory
Authors: Xiao Chunhua , Zhang Lin , Zhou Mingliang
Published: October 2021

The nonvolatile main memory (NVMM) has the advantages of near-DRAM speed, byte-addressability, and persistence, and presents limitations in write durability. The memory allocator, a fundamental data structure of memory management, can effectively mitigate the wear speed, thereby prolonging the NVMM lifetime. Nevertheless, balancing the performance and writing reliability in single and multi-thread scenarios is still an open problem for NVMM allocators. In this paper, we propose a thread-level wear-aware allocator (Tnvmalloc) that divides the NVMM space into multiple management granularities and then dynamically selects the optimal blocks using a wear-leveling strategy based on allocation requests and wear records. Experiments show that the proposed Tnvmalloc provides more than 10 times improvement in wear-leveling than typical allocators Glibc malloc, NVMalloc, and nvm_malloc, which becomes obvious especially in multi-threaded scenarios. Moreover, when allocating large memory blocks, Tnvmalloc achieves three times faster than that of NVMalloc.
Stability for the training of deep neural networks and other classifiers
Authors: Berlyand Leonid , Jabin Pierre-Emmanuel , Safsten C. Alex
Published: October 2021

We examine the stability of loss-minimizing training processes that are used for deep neural networks (DNN) and other classifiers. While a classifier is optimized during training through a so-called loss function, the performance of classifiers is usually evaluated by some measure of accuracy, such as the overall accuracy which quantifies the proportion of objects that are well classified. This leads to the guiding question of stability: does decreasing loss through training always result in increased accuracy? We formalize the notion of stability, and provide examples of instability. Our main result consists of two novel conditions on the classifier which, if either is satisfied, ensure stability of training, that is we derive tight bounds on accuracy as loss decreases. We also derive a sufficient condition for stability on the training set alone, identifying flat portions of the data manifold as potential sources of instability. The latter condition is explicitly verifiable on the training dataset. Our results do not depend on the algorithm used for training, as long as loss decreases with training.
Optimizations of Replacement Policies for Random k-out-of-n Systems
Authors: Zhang Xiaoning , Wang Junyuan
Published: October 2021

In this paper, a random repairable [Formula: see text]-out-of-[Formula: see text] system is studied when random replacement policies are performed, where [Formula: see text] is a stochastic parameter. It is replaced before failure at a planned time [Formula: see text] or at random working cycle [Formula: see text], whichever occurs last or first. Furthermore, optimal replacement policies are obtained for the extended models with working numbers. This paper aims to find the optimal replacement policies when replacement first and last policies are performed. Expected cost rates for the first and last replacement policies are derived, and their optimal replacement policies are derived analytically. Numerical examples are given to illustrate the theoretical results.