Persistence Of Type Research Articles

Modeling smothering limit of smoldering combustion: Oxygen supply, fuel density, and moisture content

Smoldering, characterized as a slow, low-temperature, and flameless reaction process, represents one of the most persistent types of combustion phenomena. While oxygen supply is one of the governing mechanisms controlling smoldering, the specific oxygen threshold or smothering limit remains inadequately investigated. Herein, we built a physics-based 1-D computational model integrating heat-and-mass transfer and 5-step heterogeneous chemistry to investigate the oxygen threshold or smothering limit of smoldering propagation in porous pine needle beds subjected to forced internal oxidizer flow. Simulation results revealed that, the required oxidizer flow velocity or oxygen supply rate increased as the oxygen concentration decreased, and the predicted limiting oxygen concentration (LOC) was about 3 %, agreeing well with the experimental observations and theoretical analysis. Moreover, the required airflow velocity was predicted to increase as the fuel density and environmental temperature decreased, or the moisture content increased, and the predicted maximum moisture content capable of supporting smoldering was about 110 %. At the smothering limit, the modeled minimum smoldering temperature and propagation rate were around 300 °C and 0.5 cm/h. This work helps deepen our understanding of the limiting conditions of smoldering combustion, thus improving the mitigation strategy of smoldering fire and the efficiency of applied smoldering systems. Novelty and significance statementsOxygen supply is one of the key mechanisms governing the smoldering propagation. In the literature, scattered studies have examined the limiting oxygen concentration (LOC) of smoldering under different conditions, leading to disparate results even for the same fuels. In our previous work, for the first time, we developed a tubular smoldering reactor capable of precisely controlling the flow of oxidizer, and successfully quantified the exact oxygen supply limit of smoldering combustion. However, no computational model was established specifically for the oxygen threshold of smoldering with forced internal oxygen supply.The novelty of this research is the establishment of the first-ever computational model to investigate the oxygen threshold or smothering limit of smoldering propagation in porous pine needle beds subjected to forced internal oxidizer flow. It is significant because (1) it contributes to a fundamental understanding of smoldering combustion; (2) it investigates the role of fuel properties and environmental conditions in smoldering dynamics and the oxygen supply limits; (3) it assists in optimizing the applied smoldering systems and enriching prevention strategies for smoldering fires.

Identification of Critical Slowing of Conduction Using Unipolar Atrial Voltage and Fractionation Mapping

BackgroundAblation strategies targeting fractionated or low-voltage potentials have been widely used in patients with persistent types of atrial fibrillation (AF). However, recent studies have questioned their role in effectively representing sites of conduction slowing, and thus arrhythmogenic substrates. ObjectivesThe authors studied the relationship between local conduction velocity (CV) and the occurrence of fractionated and/or low-voltage potentials in order to identify areas with critically slowing of conduction. MethodsIntraoperative epicardial mapping was performed during sinus rhythm. Unipolar potentials with an amplitude <1.0 mV were initially classified as low-voltage and potentials with ≥3 deflections as fractionation. A range of thresholds were also explored. Local CV was computed using discrete velocity vectors. ResultsA total of 319 patients were included. Fractionated, low-voltage potentials were rare, accounting for only 0.36% (Q1-Q3: 0.15%-0.78%) of all atrial sites. Local CV at sites with fractionated, low-voltage potentials (46.0 cm/s [Q1-Q3: 22.6-72.7 cm/s]) was lowest compared with sites with either low-voltage, nonfractionated potentials (64.5 cm/s [Q1-Q3: 34.8-99.4 cm/s]) or fractionated, high-voltage potentials (65.9 cm/s [Q1-Q3: 41.7-92.8 cm/s]; P < 0.001). Slow conduction areas (CV <50 cm/s) could be most accurately identified by using a low voltage threshold (<1 mV) and a minimum of 3 deflections (positive predictive value: 54.2%-70.7%), although the overall sensitivity remained low (0.1%-1.9%). ConclusionsSites with fractionated, low-voltage potentials have substantially slower local CV compared with sites with either low-voltage, nonfractionated potentials or fractionated, high-voltage potentials. However, the strong inverse relationship between the positive predictive value and sensitivity of a combined voltage and fractionation threshold for slowed conduction is likely to complicate the use of these signal-based ablation approaches in AF patients.

Sexual Dimorphism in Commercially Important Fish Species in India: A Review

Sexual dimorphism in fishes is an important biological aspect, which helps distinguish males and females based on various primary and secondary sexual characteristics. Based on sexual dimorphic characteristics fishes can be categorized as monomorphic, temporary dimorphic and permanent dimorphic. These characters can be either persistent or non-persistent types in fishes. Sexual dimorphism also can be determined using biometric characteristics as well. In fish, males typically display more conspicuous sexual characteristics compared to females, including the development of vibrant colouration, nuptial tubercles, or the formation of accessory organs. Sexual dimorphism is a significant trait helpful in categorizing and classifying fish species more accurately. It also has significant implications for commercial fisheries, which can aid in catch from the wild. This also can contribute to understanding the intricacies of aquatic ecosystems but also underscores the practical applications of studying sexual dimorphism in the context of sustainable fisheries management.

Permanent and Persistent Atrial Fibrillations Are Independent Risk Factors of Mortality after Severe COVID-19.

Background: The new coronavirus disease (COVID-19), a pandemic infection caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), had a deep global influence on morbidity and mortality profiles. Comorbidities, especially cardiovascular diseases, were identified to strongly modify the clinical course of COVID-19. However, the prognostic role of incident or prevalent atrial fibrillation has not been fully explained. The aim of this study was to evaluate the association between atrial fibrillation and outcomes following hospitalization in patients with severe COVID-19. Methods: We analyzed 199 patients (72 female, median age 70 years) with severe COVID-19 hospitalized between November 2020 and February 2021, due to SARS-CoV-2 infection. The study cohort included 68 patients with a history of AF (34 patients with paroxysmal AF, 19 with permanent AF, 15 patients with persistent AF), and 51 patients presented with AF during hospitalization. Results: Overall mortality during 90 days from the admission to hospital was 41% (n = 82). Non-survivors were older, had significantly elevated inflammation markers (CRP, WBC, procalcitonin, IL-6), NT-proBNP and D-dimer on the first day of hospitalization, lower left ventricular ejection fraction and worse kidney function, as compared to those who stayed alive during the follow-up. Among the hospitalized patients with COVID-19, a history of AF and the presence of AF during hospitalization contributed to higher mortality. Patients with permanent and persistent AF were at the highest risk of death. Different presentations of AF (any history of AF, the subtypes of AF-paroxysmal, permanent, persistent-and the presence of AF during hospitalization) were included in multivariate analysis, aiming to identify independent risk factors of death in the study period. We found that AF was related to worse prognosis, and persistent or permanent forms represented an independent predictor of mortality. Conclusions: Different clinical presentations of AF have varying impacts on survival in severe COVID-19. Mortality in hospitalized patients with severe COVID-19 was higher among patients with a history of AF, especially with persistent and permanent types of AF, and with AF present during hospitalization.

Predicting atrial fibrillation ablation success: a novel approach using pre-procedure sinus rhythm ecg and deep learning

Abstract Introduction Pulmonary vein isolation (PVI) has been the corner stone of the treatment of patients with atrial fibrillation (AF), yet its efficacy varies notably between patient groups. Specifically, it shows reduced efficacy in individuals with persistent AF and those with atrial fibrosis. Recent advancements suggest that additional substrate modification could enhance outcomes in specific patient groups. Therefore, predicting the outcomes of lone PVI could help in stratifying patients who would benefit most from this additional substrate modification. Addressing this gap, our study explores the prognostication of PVI outcomes using pre-procedural 12-lead ECG recordings taken in Sinus rhythm, employing advanced deep learning techniques. Methods This retrospective study analyzed 209 patients with paroxysmal and persistent AF who underwent PVI. These patients were followed up for 12 months after the blanking period. Pre-procedural sinus rhythm 12-lead ECGs were processed using an innovative deep learning architecture, integrating Long Short-Term Memory and Convolutional Neural Networks with a cross-attention module. This multimodal deep learning model was trained using ECG and clinical covariates like age, sex, and BMI to predict binary outcomes – AF type (Paroxysmal or Persistent) and AF recurrence. The model's efficacy was evaluated through a 5-fold stratified cross-validation to ensure accuracy and reliability. Model was also tested using only ECG data. Results The multimodal deep learning model performed significantly better as compared to the model trained using ECG data only. The multimodal deep learning model achieved an accuracy of 75.56% and a sensitivity of 82% in prognosticating ablation outcomes. Additionally, the model demonstrated a significant capability in classifying AF into paroxysmal or persistent types with an accuracy of 86.67% and a recall of 89%. Conclusion Our deep learning approach in analyzing sinus rhythm ECG recordings shows promising results in predicting PVI outcomes and identifying AF types. This approach could offer a more accessible and cost-effective tool to stratify AF patients undergoing PVI, identifying those less likely to benefit from standard procedures. Such insights can assist physicians and patients in determining ablation candidacy and selecting the most appropriate ablation strategy and technique.Proposed StrategyDeep learning model approach

From samples to persistent stratified homotopy types

From samples to persistent stratified homotopy types

Circulating levels of potential markers of ischemic stroke in patients with the different forms of atrial fibrillation and chronic heart failure

Atrial fibrillation (AF) is the most common abnormal type of heart rhythm (cardiac arrhythmia), which is considered the leading cause of stroke. There have been limited studies on the prognostic markers for atrial disease and AF-associated ischemic stroke, despite the high demand for this procedure in daily clinical practice to monitor disease course and assess risk of stroke in patients with AF and chronic heart failure (CHF). Thus, the aim of the present study was to evaluate the levels of serum biomarkers related to ischemic stroke in CHF patients with the different forms of AF. Forty-six patients with various types of AF (paroxysmal, persistent and permanent) with or without ischemic stroke were enrolled in the study, 36 clinically healthy donors served as a control. The levels of inducible nitric oxide synthase (iNOS), vascular endothelial growth factor (VEGF) and angiostatins (AS) were evaluated by western blot analysis in the serum. The levels of active matrix metalloproteinases (MMPs) were analysed by gelatin zymography. Elevated levels of iNOS were shown in patients with all AF forms as compared with control, but iNOS levels in post-ischemic patients were significantly higher than that in paroxysmal AF individuals. However, the levels of VEGF and AS did not differ from the baseline value in patients with paroxysmal AF, while dramatic increase of their contents was shown in post-stroke patients with persistent and permanent types of AF. Elevated active MMP-9 levels were shown to be associated with the diagnosis of all AF forms, regardless of the occurrence of stroke. Taken together, our findings­ demonstrate that tested proteins can be considered as valuable biomarkers of AF forms transformation and potentially useful for ischemic stroke risk stratification in patients with AF and CHF. Observed changes in regulatory protein levels may expand our understanding of pathological roles of endothelial function dysregulation, disrupted angiogenesis balance and abnormal tissue remodeling in AF and associated ischemic events. Keywords: angiostatins, atrial fibrillation, biomarkers, iNOS, ischemic stroke, MMP-9, VEGF

Effectiveness of inosine pranobex in the treatment and prevention of infectious diseases (system review)

The purpose of the article is a systematic review of studies conducted in recent decades in children and adults, with an emphasis on domestic works, on the use of inosine pranobex preparations, in the treatment of infectious diseases. The clinical and immunological effectiveness of inosine pranobex in the treatment and prevention of relapses in patients with recurrent respiratory viral infections against the background of persistent herpesviruses types 4-6 has been demonstrated. Using the example of multicenter comparative as well as placebo-controlled studies, not only the effectiveness, but also the safety of long-term courses of therapy is shown. A promising direction is the use of inosine pranobex in the treatment of COVID-19 and post-Covid conditions, taking into account its immunomodulatory effect without the risk of increasing the “cytokine storm”, as well as studies of the direct antiviral effect on the SARS-CoV-2 virus in vitro.

Microbial metabolism influences microplastic perturbation of dissolved organic matter in agricultural soils.

An estimated 258 million tons of plastic enter the soil annually. Joining persistent types of microplastic (MP), there will be an increasing demand for biodegradable plastics. There are still many unknowns about plastic pollution by either type, and one large gap is the fate and composition of dissolved organic matter (DOM) released from MPs as well as how they interact with soil microbiomes in agricultural systems. In this study, polyethylene MPs, photoaged to different degrees, and virgin polylactic acid MPs were added to agricultural soil at different levels and incubated for 100days to address this knowledge gap. We find that, upon MP addition, labile components of low aromaticity were degraded and transformed, resulting in increased aromaticity and oxidation degree, reduced molecular diversity, and changed nitrogen and sulfur contents of soil DOM. Terephthalate, acetate, oxalate, and L-lactate in DOM released by polylactic acid MPs and 4-nitrophenol, propanoate, and nitrate in DOM released by polyethylene MPs were the major molecules available to the soil microbiomes. The bacteria involved in the metabolism of DOM released by MPs are mainly concentrated in Proteobacteria, Actinobacteriota, and Bacteroidota, and fungi are mainly in Ascomycota and Basidiomycota. Our study provides an in-depth understanding of the microbial transformation of DOM released by MPs and its effects of DOM evolution in agricultural soils.

Heatwave exposure in relation to decreased sleep duration in older adults

Few studies have delved into the effects of heatwaves on sleep duration loss among older adults. Our study examined correlations between heatwave exposure and sleep duration reductions in this demographic. Utilizing data of 7,240 older adults drawn from the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2018, we assessed sleep duration differences between the baseline year (2015) and follow-up year (2018). Absolute reductions in sleep duration were defined as differences of ≥ 1, 1.5, or 2 h. Changes in sleep duration were categorized based on cut-offs of 5 and 8 h, including excessive decrease, moderate to short and persistent short sleep duration types. 12 heatwave definitions combining four thresholds (90th, 92.5th, 95th, and 97.5th percentiles of daily minimum temperature) and three durations (≥2, ≥3 and ≥ 4 days) were used. Heatwave exposure was determined by the difference in the number of 12 preceding months' heatwave days or events in 2015 and the number of 12 preceding months' heatwave days or events in 2018. The results showed that increased heatwave events (defined as ≥ P90th percentile & lasting three days) were associated with a higher likelihood of ≥ 1-hour sleep reduction and persistent short sleep duration. An increase in heatwave event (defined as ≥ P95th percentile & lasting three days) was linked to shifts from moderate to short sleep duration. For the association between an absolute reduction in sleep duration and heatwave exposure, while higher thresholds signified greater sleep reduction risks, the effect estimates of longer durations were not uniformly consistent. We observed that air pollution and green space modified the relationship between heatwaves and sleep duration. Females, urban residents, and individuals with chronic diseases were identified as vulnerable populations. This study found that increased heatwave exposure was associated with a higher risk of sleep duration loss in older adults.

HPV-related lesions after hysterectomy for high-grade cervical intraepithelial neoplasia and early-stage cervical cancer: A focus on the potential role of vaccination.

To date, no data supports the execution of vaccination after hysterectomy for high-grade cervical intraepithelial neoplasia (CIN2+) and early-stage cervical cancer. We aim to evaluate the potential effect of vaccination after hysterectomy for high-grade cervical intraepithelial neoplasia and early-stage cervical cancer. This is a multi-center retrospective study evaluating data of women who develop lower genital tract dysplasia (including anal, vulvar and vaginal intra-epithelial neoplasia) after having hysterectomy for CIN2+ and FIGO stage IA1- IB1 cervical cancer. Overall, charts for 77 patients who developed lower genital tract dysplasia were collected. The study population included 62 (80.5%) and 15 (19.5%) patients with CIN2+ and early-stage cervical cancer, respectively. The median (range) time between hysterectomy and diagnosis of develop lower genital tract dysplasia was 38 (range, 14-62) months. HPV types covered by the nonavalent HPV vaccination would potentially cover 94.8% of the development of lower genital tract dysplasia. Restricting the analysis to the 18 patients with available HPV data at the time of hysterectomy, the beneficial effect of nonvalent vaccination was 89%. However, considering that patients with persistent HPV types (with the same HPV types at the time of hysterectomy and who developed lower genital tract dysplasia) would not benefit from vaccination, we estimated the potential protective effect of vaccination to be 67% (12 out of 18 patients; four patients had a persistent infection for the same HPV type(s)). Our retrospective analysis supported the adoption of HPV vaccination in patients having treatment for HPV-related disease. Even in the absence of the uterine cervix, HPV vaccination would protect against develop lower genital tract dysplasia. Further prospective studies have to confirm our preliminary research.

Roles of Dynamic and Thermodynamic Processes in Regulating the Decay Paces of El Niño Events

Abstract Most El Niño events decay after a peak in boreal winter, but some persist and strengthen again in the following year. Several mechanisms for regulating its decay pace have been proposed; however, their relative contributions have not been thoroughly examined yet. By analyzing the fast-decaying and persistent types of the events in a 1200-yr coupled simulation, we quantify the key dynamic and thermodynamic processes in the decaying spring that are critical to determining the decay pace of El Niño. The zonal advection due to upwelling Kelvin wave accounts for twice as much the cooling difference as evaporation or meridional advection does. The upwelling Kelvin wave is much stronger in the fast-decaying events than the others, and its strength is equally attributed to the reflected equatorial Rossby wave and the equatorial easterly wind forcing over the western Pacific in the preceding 2–3 months. Relative to the fast-decaying events, the evaporative cooling is weaker but the meridional warm advection is stronger in the persistent events. The former is due to more meridionally asymmetric wind and sea surface temperature anomalies (SSTA) signaling positive Pacific meridional mode. The latter results from the advection of equatorial warm SSTA by climatological divergent flow, and the warmer SSTA persists from the mature stage subject to weaker cloud-radiative cooling in response to the central-Pacific-type SSTA distribution in the persistent events relative to the fast-decaying events. Our result consolidates the existing knowledge and provides a more comprehensive and physical pathway for the causality of El Niño’s diverse duration.

Performing Asian/American Women

The transnational circulation of persistent racial types that are attached to Asian/American women have shaped Asian-focused narratives and roles on Broadway. The King and I (2015) and KPOP (2022) exemplify Asian/American women’s performative labor and the tensions embedded in and disruptive of the contested political arena of Broadway musical theatre.

Quantitative Investigation of Methylation Heterogeneity by Digital Melting Curve Analysis on a SlipChip for Atrial Fibrillation.

Methylation is an essential epigenetic modification involved in regulating gene expression and maintaining genome stability. Methylation patterns can be heterogeneous, exhibiting variations in both level and density. However, current methods of methylation analysis, including sequencing, methylation-specific PCR, and high-resolution melting curve analysis (HRM), face limitations of high cost, time-consuming workflows, and the difficulty of both accurate heterogeneity analysis and precise quantification. Here, a droplet array SlipChip-based (da-SlipChip-based) digital melting curve analysis (MCA) method was developed for the accurate quantification of both methylation level (ratio of methylated molecules to total molecules) and methylation density (ratio of methylated CpG sites to total CpG sites). The SlipChip-based digital MCA system supplements an in situ thermal cycler with a fluorescence imaging module for real-time MCA. The da-SlipChip can generate 10,656 droplets of 1 nL each, which can be separated into four lanes, enabling the simultaneous analysis of four samples. This method's clinical application was demonstrated by analyzing samples from ten healthy individuals and twenty patients with atrial fibrillation (AF), the most common arrhythmia. This method can distinguish healthy individuals from those with AF of both the paroxysmal and persistent types. It also holds potential for broader application in various research and clinical settings requiring methylation analysis.

A Quantitative Theory of the Credit Score

What is the role of credit scores in credit markets? We argue that it is, in part, the market's assessment of a person's unobservable type, which here we take to be patience. We postulate a model of persistent hidden types where observable actions shape the public assessment of a person's type via Bayesian updating. We show how dynamic reputation can incentivize repayment. Importantly, we show how an economy with credit scores implements the same equilibrium allocation. We estimate the model using both credit market data and the evolution of individuals' credit scores. We conduct counterfactuals to assess how more or less information used in scoring individuals affects outcomes and welfare. If tracking of individual credit actions is outlawed, poor young adults of low type benefit from subsidization by high types despite facing higher interest rates arising from lower dynamic incentives to repay.

Combining Remote Sensing and Space-Time Analysis for Desertification Monitoring in the Semiarid Dryland of Nigeria

Desertification has been identified as the resultant effect of dryland loss. Desertification is catalysed by anthropogenic modifications and variations in environmental/climatic conditions. The situation in Nigeria is further exacerbated by the growing demand for land by the population. To this effect, this study performed a space-time analysis of vegetative cover between 2001 and 2020 to unravel patterns and trends across the semiarid region of the dryland system in Nigeria. The dynamics during the rainy season (May and September) were examined using the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) dataset subjected to space-time analysis. Generalised Difference Vegetation Index (GDVI) was computed to the power of 2 to quantify vegetative cover across the study area. The results showed that the average of the GDVI ranges between -0.40 and 0.94, with a standard deviation of 0.11. Time series cluster analysis revealed that there are two temporal clusters: (1) no statistically significant trend (Statistics= 1.33, p-value = 0.18) and (2) statistically significant downtrend (Statistics = -2.37, p=0.02), with cluster 1 covering 95% of the areas examined. The most dominant (97% of the area) emerging space-time pattern was cold-spots (persistent, diminishing, sporadic, oscillating, and historical types). In conclusion, most of the areas showed no definite temporal pattern of vegetation pattern during the period, while more than 90% of the areas have witnessed a decline in vegetative cover. There is a need for a more coordinated approach to desertification control, constant monitoring is pertinent while new approaches to restoring degraded land are recommended.

Prevalence and Characteristics of Persistent Symptoms in Children During the COVID-19 Pandemic: Evidence From a Household Cohort Study in England and Wales.

Prevalence and Characteristics of Persistent Symptoms in Children During the COVID-19 Pandemic: Evidence From a Household Cohort Study in England and Wales.

Long COVID symptoms in a population-based sample of persons discharged home from hospital.

ObjectivesThe impact of long COVID among persons hospitalized and discharged home is unknown. We aimed to (1) report the prevalence of long COVID in persons hospitalized for COVID-19 and discharged home; (2) estimate the prevalence of physical, sensory, and psychological/mental health impairments; and (3) explore associated factors.MethodsWe conducted a telephone survey of adult residents in Laval, Quebec, who were discharged home ≥ 2 months post-hospitalization for COVID-19. Participants responded to a standard questionnaire regarding persistent symptoms. We calculated the prevalence of long COVID and of persistent types of symptoms and evaluated associated factors using bivariate analysis and multivariable logistic regression.ResultsIn our sample (n = 398), 70% reported physical symptoms, 58% psychological problems, and 16% sensory impairments. 31.5% reported being troubled by persistent symptoms (long COVID). Factors associated with long COVID were a greater number of symptoms (odds ratio (OR) = 1.97, 95% confidence interval (CI) = 1.69–2.28) and increased hospital stay (OR = 1.03, 95% CI = 1.01–1.06). Other factors associated with physical and psychological symptoms were female sex (OR = 2.17, 95% CI = 1.27–3.71 and OR = 2.06, 95% CI = 1.25–3.39; respectively), higher education level (OR = 2.10, 95% CI = 1.20–3.68 and OR = 2.43, 95% CI = 1.44–4.14; respectively), and obesity (OR = 1.95, 95% CI = 1.15–3.34 and OR = 1.70, 95% CI = 1.05–2.77; respectively).ConclusionIn this population-based study of persons hospitalized for COVID-19 and discharged home, nearly one third were troubled by symptoms for 2 months or more post-discharge. There was a high proportion with persistent physical and psychological/mental health symptoms. Further research will assess the specific needs of these patients to inform health policy makers on service requirements for these persons.

Is This Stalking? Perceptions and Victimization Experiences of Stalking and Intrusive Behaviors in Hong Kong, Mainland China, and Ghana.

Many studies of stalking and intrusive behaviors are conducted with samples from individualist Western cultures, and limited information is available on such behavior in collectivist cultures. By using a sample of 1143 adults (440 males and 703 females) from Hong Kong (n = 305), mainland China (n = 464), and Ghana (n = 374), this study compares perceptions and experiences of stalking and intrusive behaviors as well as the frequency and duration of the participants’ worst experiences with such behaviors. The lifetime prevalence rate of stalking victimization for the overall sample was 34.6%, 22.3% for the Hong Kongers, 32.3% for the mainland Chinese, and 47.3% for the Ghanaians. Relative to the Hong Kongers and Ghanaians, the mainland Chinese were more likely to judge most intrusive activities as unacceptable. However, the mainland Chinese were generally less likely to have experienced the listed intrusive activities than their counterparts. The Ghanaians, in contrast, reported significantly more victimization experiences than the Hong Kongers and the mainland Chinese, especially with aggression and surveillance, unwanted attention, and persistent courtship and imposition types of behaviors. Furthermore, the mainland Chinese and Ghanaians generally reported significantly higher frequencies of stalking and intrusive behavior in their worst experiences than did the Hong Kongers. Conversely, the Hong Kongers and Ghanaians reported significantly more persistent types of stalking and intrusive behaviors than the mainland Chinese. The results of this study indicate the need for anti-stalking legislation in Hong Kong, mainland China, and Ghana, given the devastating nature and consequences of stalking and intrusive behaviors there.

0720 Accuracy of WatchPat Portable Sleep Monitoring and Sleep Assessment in Patients with Atrial Fibrillation

Abstract Introduction Obstructive sleep apnea(OSA) is an established risk factor for atrial fibrillation(AF), necessitating early diagnosis and management. Home-based sleep-monitoring technology has become a mainstream diagnostic modality. Peripheral arterial tonometry (PAT) device is increasingly being used to screen for OSA in patients with AF. Our study aimed to examine the accuracy of Watch-PAT (WP) in OSA evaluation, and night-to-night variability of sleep characteristics as measured by WP when used during consecutive night sleep studies. Methods Patients with history of AF undergoing clinically indicated PSG were prospectively enrolled and had concurrent WP while undergoing PSG. Patients then were studied again using WP over two consecutive days at home. We compared agreement of OSA severity(defined as no OSA[AHI (apnea hypopnea index)&amp;lt;5], mild OSA[15&amp;gt;AHI³5], moderate OSA[30&amp;gt;AHI³15], severe OSA[AHI&amp;gt;30]) and total sleep time(TST) using Cohen’s Kappa(K) for categorical and Bland-Altman plots for continuous variables. To further characterize PSG versus WP, the cohort was stratified into paroxysmal versus persistent AF types. 1A/1B hypopnea scoring criteria was defined as per AASM. Results Our cohort included 24 patients with AF(80% male, mean age 68y). Most patients had clinically defined OSA(AHI³5). Patients with persistent AF had more severe OSA than those with paroxysmal AF (severe OSA present in 60% vs. 29%). Comparison of PSG to concurrently conducted WP in the lab showed substantial agreement in OSA severity by both 1A(K=0.623) and 1B(0.706) criteria. Percent difference in TST between PSG versus WP in the paroxysmal AF versus persistent groups was not statistically significant(p=0.387). Comparing two consecutive at-home WP tests showed substantial agreement in OSA severity measures(1A=0.872,1B=0.889). Bland-Altman plots for TST and sleep architecture showed ³95% of residuals within 2 standard-deviations, suggesting intertester agreement. Confidence intervals were broad in these plots reflecting our small sample size. Conclusion Our findings demonstrate that WP is a reasonable alternative to PSG, particularly if using the 1B criteria to diagnose OSA. Additionally, our results show that persistent versus paroxysmal AF does not seem to affect the results of WP tests. Night to night variability of OSA measures and TST was small. Future studies should verify the results of our study in a larger cohort. Support (If Any)