bluuebunny/crossref_metadata_2025 huggingface dataset:
MODELING TOURISM–ENVIRONMENT RELATIONSHIP IN AUSTRALIA: DOES ASYMMETRY MATTER?
Authors: ACHEAMPONG ALEX O.
Published: December 2021

Prior empirical studies have employed various econometric estimation techniques to study the environmental effect of tourism demand. Prominently, these econometric modeling techniques implicitly assume that the environmental effect of tourism is symmetrical, which could sometimes be problematic. This study, therefore, utilized two econometric estimation techniques, namely, the Pesaran et al. ( 2001 ). Bounds testing approaches to the analysis of level relationships. Journal of Applied Econometrics, 16(3), 289–326) symmetric autoregressive distributed lag (ARDL) and Shin et al. ( 2014 ). Modelling asymmetric cointegration and dynamic multipliers in a nonlinear ARDL framework. In Festschrift in Honor of Peter Schmidt, pp. 281–314. New York: Springer) nonlinear ARDL (NARDL) estimation technique to disentangle the effect of tourism demand on carbon emissions in Australia. The results from the symmetric ARDL model reveal that tourism demand significantly increases carbon emissions in the long run, indicating that a 1% increase in tourism demand contributes to a 0.155% increase in carbon emissions in the long run. Contrarily, the NARDL model shows that a positive shock (an increase) in tourism demand reduces carbon emissions while a negative shock (a decrease) in tourism demand increases carbon emissions in the long run. From the NARDL estimate, a 1% increase in tourism demand is associated with a 0.220% decline in carbon emissions, while a 1% decrease in tourism demand increases carbon emissions by 0.250%. Therefore, I argue that carbon emissions depend not only on the size of tourism demand but also on the pattern — thus the increase and decline — of tourism demand. The implications of these results for policy are discussed.
Artificial Intelligence-Based Quality Management and Detection System for Personalized Learning
Authors: Yu Haixia , Wang Jidong , Murugesan Mohanraj , Rahman A. B. M. Salman
Published: December 2021

Recently, the teaching and learning method in the conventional engineering education system needs a group of learners with personalized learning paths. The introduction of technologies like Artificial Intelligence will aid the learners to identify and detect learning opportunities utilizing historical information, present student profile and success data from an institution, and recommend learning measures to enhance their performance. This study proposes an Artificial Intelligence-based Meta-Heuristic Approach (AIMHA) for personalized learning detection systems and quality management. The proposed model has been utilized to optimize learning effectiveness by considering the nature of the learning path and the number of simultaneous visits to every learning action. In addition, a quality resolution can be determined by a meta-heuristic approach. The simulation findings of the learning actions have been utilized to examine the efficiency of the suggested method. The proposed method is evaluated learning activities achieved an efficiency ratio of 92.3%, sensitivity analysis ratio of 88.4%, performance ratio of 92.3%, precision ratio of 94.3% compared to other existing models.
INVESTOR SENTIMENT CONNECTEDNESS: EVIDENCE FROM LINEAR AND NONLINEAR CAUSALITY APPROACHES
Authors: TIWARI AVIRAL KUMAR , BATHIA DEVEN , BOURI ELIE , GUPTA RANGAN
Published: December 2021

This paper provides a novel perspective in determining the Granger causality of sentiment across the US, Latin America, Eurozone, Japan and Asia (excluding Japan), based on monthly data covering the period of January 2003–November 2017. Using a survey-based sentiment index of “sentix”, our results suggest strong evidence of nonlinearity and structural breaks making the use of linear causality models unreliable. Using a kernel-based multivariate nonlinear causality test, we find that causality runs from Eurozone to the US, Asia and Japan, with Japan also causing the Eurozone sentiment, and Latin America causing the Japanese sentiment. Interestingly, when we apply rolling estimations to detect time-varying causality for the cases of Eurozone and the US, Eurozone and Asia, Eurozone and Japan and Latin America and Japan, the results suggest evidence of bidirectional spillovers during certain months of the recent global financial crisis, and thereafter. Overall, our findings indicate that the sentiments of Japan, Asia and the US are related quite strongly with that of the Eurozone, as well as the sentiments of Japan and Latin America.
A Shaky “Wedge”: An Analysis of India’s Strategic Behavior under the US “Indo-Pacific” Strategy
Authors: Lian Bo
Published: December 2021

America’s Indo-Pacific strategy is essentially a combination of its Asia-Pacific and Indian strategies: through the consolidation of its strategic alliances, it can deepen its relations with Asia-Pacific allies, and through its “wedging strategy” it can pull India into its orbit to become a strategic “fulcrum” bridging the region. India was both a key member and leader of the non-aligned movement, while also previously forming a “quasi-alliance” with the Soviet Union. At present, it has responded to the US Indo-Pacific strategy with cautious initiative. From the vantage point of a state targeted vis-à-vis a wedging strategy, India’s strategic behavior is shaped by the strategic environment, its primary strategic objectives, and the relations between allies within the context of a unique strategic environment. This paper identifies two types of strategic environments: the general strategic environment and the specialized strategic environment; it further identifies primary strategic objectives as economic development, sovereign integrity and independence, national security and great state status (especially with respect to that of regional or global major powers); meanwhile, the alliance relationship is defined according to the extent to which there are divisions across state interests and the capacity of states to act autonomously vis-à-vis the alliance. Through an analysis of India’s diplomatic experiences, this paper argues that against the backdrop of America’s “Indo-Pacific” strategy and a lose general strategic environment, the primary strategic objective of achieving major state status and a “large divide over interests and a major space for autonomous action” shape India’s cautious initiative with respect to its alliance relationships.
PARP: A Parallel Traffic Condition Driven Route Planning Model on Dynamic Road Networks
Authors: Dai Tianlun , Li Bohan , Yu Ziqiang , Tong Xiangrong , Chen Meng , Chen Gang
Published: December 2021

The problem of route planning on road network is essential to many Location-Based Services (LBSs). Road networks are dynamic in the sense that the weights of the edges in the corresponding graph constantly change over time, representing evolving traffic conditions. Thus, a practical route planning strategy is required to supply the continuous route optimization considering the historic, current, and future traffic condition. However, few existing works comprehensively take into account these various traffic conditions during the route planning. Moreover, the LBSs usually suffer from extensive concurrent route planning requests in rush hours, which imposes a pressing need to handle numerous queries in parallel for reducing the response time of each query. However, this issue is also not involved by most existing solutions. We therefore investigate a parallel traffic condition driven route planning model on a cluster of processors. To embed the future traffic condition into the route planning, we employ a GCN model to periodically predict the travel costs of roads within a specified time period, which facilitates the robustness of the route planning model against the varying traffic condition. To reduce the response time, a Dual-Level Path (DLP) index is proposed to support a parallel route planning algorithm with the filter-and-refine principle. The bottom level of DLP partitions the entire graph into different subgraphs, and the top level is a skeleton graph that consists of all border vertices in all subgraphs. The filter step identifies a global directional path for a given query based on the skeleton graph. In the refine step, the overall route planning for this query is decomposed into multiple sub-optimizations in the subgraphs passed through by the directional path. Since the subgraphs are independently maintained by different processors, the sub-optimizations of extensive queries can be operated in parallel. Finally, extensive evaluations are conducted to confirm the effectiveness and superiority of the proposal.
Predicting Human Mobility with Reinforcement-Learning-Based Long-Term Periodicity Modeling
Authors: Tao Shuo , Jiang Jingang , Lian Defu , Zheng Kai , Chen Enhong
Published: December 2021

Mobility prediction plays an important role in a wide range of location-based applications and services. However, there are three problems in the existing literature: (1) explicit high-order interactions of spatio-temporal features are not systemically modeled; (2) most existing algorithms place attention mechanisms on top of recurrent network, so they can not allow for full parallelism and are inferior to self-attention for capturing long-range dependence; (3) most literature does not make good use of long-term historical information and do not effectively model the long-term periodicity of users. To this end, we propose MoveNet and RLMoveNet. MoveNet is a self-attention-based sequential model, predicting each user’s next destination based on her most recent visits and historical trajectory. MoveNet first introduces a cross-based learning framework for modeling feature interactions. With self-attention on both the most recent visits and historical trajectory, MoveNet can use an attention mechanism to capture the user’s long-term regularity in a more efficient way. Based on MoveNet, to model long-term periodicity more effectively, we add the reinforcement learning layer and named RLMoveNet. RLMoveNet regards the human mobility prediction as a reinforcement learning problem, using the reinforcement learning layer as the regularization part to drive the model to pay attention to the behavior with periodic actions, which can help us make the algorithm more effective. We evaluate both of them with three real-world mobility datasets. MoveNet outperforms the state-of-the-art mobility predictor by around 10% in terms of accuracy, and simultaneously achieves faster convergence and over 4x training speedup. Moreover, RLMoveNet achieves higher prediction accuracy than MoveNet, which proves that modeling periodicity explicitly from the perspective of reinforcement learning is more effective.
Novel Method for Monitoring the Electrochemical Capacitance by In Situ Impedance Spectroscopy as Indicator for Particle Cracking of Nickel-Rich NCMs: Part II. Effect of Oxygen Release Dependent on Particle Morphology
Authors: Oswald Stefan , Pritzl Daniel , Wetjen Morten , Gasteiger Hubert A.
Published: December 2021

Nickel-rich NCMs (LiMO2, with M = Ni, Co, and Mn) are increasingly commercialized as cathode active materials for lithium-ion batteries due to their high specific capacity. However, the available capacity is limited due to their structural instability at high state of charge, causing the formation of a resistive surface layer upon release of lattice oxygen, observed at different upper cutoff potentials depending on the NCM composition. To understand the impact of this instability, the correlation of oxygen release, capacity fading, and particle cracking was investigated as a function of state of charge for three nickel-rich NCMs, differing either in composition (i.e., in transition metal ratio) or in morphology (i.e., in primary crystallite size). First, the onset of the release of lattice oxygen was identified by on-line electrochemical mass spectrometry (OEMS). In electrochemical cycling experiments, the NCM capacitance was tracked in situ by impedance spectroscopy (EIS) using a micro-reference electrode while the upper cutoff potential was increased every third cycle stepwise from 3.9 V to 5.0 V. Hereby, the effect of the degree of delithiation on the discharge capacity and on the particle integrity (tracked via its surface area) was examined, both for poly- and single-crystalline NCMs.
Metal Nanostructures: A New Class of Electronic Devices
Authors: Schwarzacher Walter
Published: December 2021

Since the discovery of the transistor just over 50 years ago (see Interface Vol. 6, No. 1), the cost of electronic systems has been reduced and their performance dramatically improved. New technology has resulted in individual components becoming ever smaller and more highly integrated. Controlling the structure of semiconductor devices on a submicron scale has become routine.
High and Low Dielectric Constant Materials
Authors: Singh Rajenda , Ulrich Richard K.
Published: December 2021

Silicon-based dielectrics (SiO2, Si3N4, SiOxNy etc.) have been widely used as the key dielectrics in the manufacturing of silicon integrated circuits (ICs) and virtually all other semiconductor devices. Dielectrics having a value of dielectric constant k × 8.854 F/cm more than that of silicon nitride (k > 7) are classified as high dielectric constant materials, while those with a value of k less than the dielectric constant of silicon dioxide (k < 3.9) are classified as the low dielectric constant materials. The minimum value of (k) is one for air. The highest value of k has been reported for relaxor ferroelectric (k = 24,700 at 1 kHz).
Pesticidal Activity of Sundarban Mangrove Plant Extracts against Sitophilus Pests and Identification of Active Constituents Using LC-MS
Authors: Rahman Md. Abdur , Paul Rinku Rani , Biswas Chaina , Akter Hakima , Rouf Razina , Nath Sushmita , Shilpi Jamil A. , Nahar Lutfun , Sarker Stayajit D. , Uddin Shaikh Jamal
Published: December 2021

Plants act as a rich source of novel natural pesticides. In the backdrop of the recent revival of interest in developing plant-based insecticides, this study was carried out to investigate the pesticidal activity of Sundarban mangrove plants. A total of nine different plant parts from five plants, namely, Aegiceras corniculatum, Excoecaria agallocha, Heritiera fomes, Xylocarpus moluccensis, and Xylocarpus granatum, were extracted with methanol and tested for insecticidal activity against two common stored product pests Sitophilus oryzae and Sitophilus zeamais using direct contact feeding deterrent wafer disc method. Three bark extracts from A. corniculatum, E. agallocha, and H. fomes showed potent and statistically significant insecticidal activity against both S. oryzae and S. zeamais pests (80–100% mortality). All the active bark extracts were further fractionated using C-18 solid-phase extraction (SPE) columns and tested for their insecticidal activity against S. oryzae pest to identify the active fraction. Only the SPE4 fraction (100% MeOH) from all the three active plants showed the activity against S. oryzae pest with a lethal concentration 50% (LC50) value of 0.5, 1.0, and 1.5 mg/disc for A. corniculatum, E. agallocha, and H. fomes, respectively. The active fraction of A. corniculatum was further profiled for identification of active compounds using LC-ESI-MS and identified (along with some unknown peaks) two previously reported compounds at m/z 625.17630 (isorhamnetin 3-O-rutinoside) and 422.25346 (paspaline) as major constituents. Insecticidal activities of these plants are reported in this study for the first time and would be useful in promoting research aiming for the development of new biopesticides from mangrove plants.
Boundedness of Convex Polytopes Networks via Local Fractional Metric Dimension
Authors: Javaid Muhammad , Zafar Hassan , Aljaedi Amer , Alanazi Abdulaziz Mohammad
Published: December 2021

Metric dimension is one of the distance-based parameter which is frequently used to study the structural and chemical properties of the different networks in the various fields of computer science and chemistry such as image processing, pattern recognition, navigation, integer programming, optimal transportation models, and drugs discovery. In particular, it is used to find the locations of robots with respect to shortest distance among the destinations, minimum consumption of time, and lesser number of the utilized nodes and to characterize the chemical compounds having unique presentation in molecular networks. The fractional metric dimension being a latest developed weighted version of the metric dimension is used in the distance-related problems of the aforementioned fields to find their nonintegral optimal solutions. In this paper, we have formulated the local resolving neighborhoods with their cardinalities for all the edges of the convex polytopes networks to compute their local fractional metric dimensions in the form of exact values and sharp bounds. Moreover, the boundedness of all the obtained results is also proved.
Strangeness Enhancement at LHC Energies Using the Thermal Model and EPOSLHC Event Generator
Authors: Hanafy Mahmoud , Qandil Omnia S. A. , Shalaby Asmaa G.
Published: December 2021

The strangeness enhancement signature of QGP formation at LHC energies is carefully tackled in the present study. Based on HRG, the particle ratios of mainly strange and multistrange particles are studied at energies from lower

s

~
0.001

up to 13 TeV. The strangeness enhancement clearly appeared at more high energies, and the ratios are confronted to the available experimental data. The particle ratios are also studied using the Cosmic Ray Monte Carlo (CRMC) interface model with its two different event generators, namely, EPOS 1.99 and EPOSlhc, which show a good agreement with the model calculations at the whole range of the energy. We utilize them to produce some particles ratios. EPOS 1.99 is used to estimate particle ratios at lower energies from AGS up to the Relativistic Heavy Ion Collider (RHIC) while EPOSlhc is used at LHC energies. The production of kaons and lambda particles is studied in terms of the mean multiplicity in p-p collisions at energies ranging from 4 to 26 GeV. We find that both HRG model and the used event generators, EPOS 1.99 and EPOSlhc, can describe the particle ratios very well. Additionally, the freeze-out parameters are estimated for different collision systems, such as p-p and Pb-Pb, at LHC energies using both models.
Comprehensive Analysis of Myoferlin in Human Pancreatic Cancer via Bioinformatics
Authors: Pi Rou , Chen Yanmei , Du Yijie , Dong Suzhen
Published: December 2021

Pancreatic cancer is the fourth leading cause of cancer‐related death and urgently needs biomarkers for clinical diagnosis and prognosis. It has been reported that myoferlin (MYOF) is implicated in the regulation of proliferation, invasion, and migration of tumor cells in many cancers including pancreatic cancer. To confirm the prognostic value of MYOF in pancreatic cancer, a comprehensive cancer versus healthy people analysis was conducted using public data. MYOF mRNA expression levels were compared in many kinds of cancers including pancreatic cancer via the Oncomine and Gene Expression Profiling Interactive Analysis (GEPIA) databases. The results have shown that MYOF mRNA expression levels were upregulated in most types of cancers, especially in pancreatic cancer, compared with healthy people’s tissues. Data from the Cancer Cell Line Encyclopedia (CCLE) and European Bioinformatics Institute (EMBL‐EML) database also revealed that MYOF mRNA is highly expressed in most cancer cells, particularly in pancreatic cancer cell lines. Furthermore, the prognostic value of MYOF was evaluated using GEPIA and Long‐term Outcome and Gene Expression Profiling Database of pan‐cancers (LOGpc) database. Higher expression of MYOF was associated with poorer overall survival, especially in the lower stage and lower grade. Coexpressed genes, possible regulators, and the correlation between MYOF expressions were analyzed via the GEPIA and LinkedOmics database. Nineteen coexpressed genes were identified, and most of these genes were related to cancer. The Tumor Immune Estimation Resource (TIMER) database was used to analyze the correlation between MYOF and immune response. Notably, we found that MYOF might have a potential novel immune regulatory role in tumor immunity. These results support that MYOF is a candidate prognostic biomarker for pancreatic cancer, which calls for further genomics research of pancreatic cancer and deeply functional studies on MYOF.
Stability of the Foundation of Buried Energy Pipeline in Permafrost Region
Authors: Li Yan , Jin Huijun , Wen Zhi , Li Xinze , Zhang Qi
Published: December 2021

During operation, a buried pipeline is threatened by a variety of geological hazards, particularly in permafrost regions, where freezing-thawing disasters have a significant influence on the integrity and safety of the buried pipelines. The topographical environmental conditions along the pipeline, as well as the influence of frost heave and thaw settlement on the pipeline’s foundation soil, must be considered in the design and construction stage. Theoretical analysis, numerical modeling, field testing, and mitigation measures on vital energy pipelines in permafrost have been widely documented, but no attempt has been made to review the freezing-thawing disasters, current research methodologies, and mitigation strategies. This article reviews the formation mechanisms and mitigation measures for frost hazards (e.g., differential frost heave, thaw settlement, slope instability, frost mounds, icing, river ice scouring, and pipeline floating) along buried pipelines in permafrost regions and summarizes and prospects the major progress in the research on mechanisms, analysis methods, model test, and field monitoring based on publications of studies of key energy pipelines in permafrost regions. This review will provide scholars with a basic understanding of the challenging freezing-thawing hazards encountered by energy pipelines in permafrost regions, as well as research on the stability and mitigation of pipeline foundation soils plagued by freezing-thawing hazards in permafrost regions under a warming climate and degrading permafrost environment.
Was Antiphospholipid Syndrome a Risk Factor of Stroke? A Systemic Review and Meta-Analysis of Cohort Studies
Authors: Zhao Kai , Zhou Ping , Xu Ling , Li Ruili , Yang Jincai , Zhang Qiang , Yang Mingfei , Wei Xiaoxing
Published: December 2021

Antiphospholipid syndrome (APS) is characterized by thrombosis. This systemic review and meta-analysis was to verify the hypothesis that APS might increase the risk of stroke. Studies were identified after literature searching of PubMed, Embase, and Cochrane. Newcastle-Ottawa Quality Assessment Scale Cohort Studies (NOQAS-C) was used to assess the quality of studies. The pooled effect with 95% confidence interval (95% CI) was calculated by random-effect model.

I

-square (

I

2

) was used to test heterogeneity. Funnel plot was used to evaluate publication bias. A total of 17 cohort studies with overall high quality were included. There was no publication bias. Pooled hazard ratio of stroke occurrence in APS patients was 1.76 (1.39-2.21) with low heterogenicity and stable result from sensitivity analysis. In the analysis of subgroups, pooled risk ratios of stroke occurrence in patients with only positive antibodies of APS diagnosis were 1.75 (0.99-3.09), which for the APS patients with other autoimmune diseases were 14.70 (7.56-28.56). APS might be a risk factor of stroke, especially in patients with other autoimmune diseases.
Research on the Intelligent Display of Cultural Relics in Smart Museums Based on Intelligently Optimized Digital Images
Authors: Sha Yutian , Zhang Shaohan , Feng Tianxin , Yang Ting
Published: December 2021

The smart museum is a new platform for the appreciation and display of cultural relics across time and space. In the era of 3D scanning technology, computer technology, and network technology, it is necessary to deeply study the smarter and more perfect forms of smart museums. This article, through the analysis of the characteristics of the display level of the smart museum, tries to create a new humanized and intelligent display of cultural relics.
Dynamic Modeling and Analysis of Multidimensional Hybrid Recommendation Algorithm in Tourism Itinerary Planning under the Background of Big Data
Authors: Hao Yange , Song Na
Published: December 2021

Smart tourism can provide high-quality and convenient services for different tourists, and tourism itinerary planning system can simplify tourists’ tourism preparation. In order to improve the limitation of the recommendation dimension of traditional travel planning system, this paper designs a mixed user interest model on the premise of traditional user interest modeling and combines various attributes of scenic spots to form personalized recommendation of scenic spots. Then, it uses heuristic travel planning cost-effective method to construct the corresponding travel planning system for travel planning. In terms of the accuracy rate of travel planning recommendation, the accuracy rate of multidimensional hybrid travel recommendation algorithm is 0.984, and the missing rate is 0. When the travel cost and travel time are the same and the number of scenic spots is 20–30, the memory occupation of MH algorithm is only 1/2 of that of TM algorithm. The results show that the multidimensional hybrid travel recommendation algorithm can improve the personalized travel planning of users and the travel time efficiency ratio. The results of this study have a certain reference value in improving user satisfaction with the travel planning system and reducing user interaction.
Clusters of Severe Eosinophilic Asthma in a Korean Asthma Cohort
Authors: Lee Ji-Hyang , An Jin , Won Ha-Kyeong , Seo Bomi , Kim Jung-Hyun , Park So-Young , Kim Min-Hye , Shin Yoo Seob , Jung Jae-Woo , Song Woo-Jung , Lee Taehoon , Kwon Hyouk-Soo , Lee Jae Hyun , Kim Joo-Hee , Kim Sae-Hoon , Chang Yoon-Seok , Cho You Sook , Nahm Dong-Ho , Jang An-Soo , Park Jung-Won , Yoon Ho-Joo , Cho Sang-Heon , Cho Young-Joo , Choi Byoung Whui , Moon Hee-Bom , Kim Tae-Bum ,   on behalf of the COREA Investigators
Published: December 2021

Background: Targeted therapies have broadened the available treatment options for patients with severe eosinophilic asthma (SEA). However, differences in the magnitude of treatment responses among patients indicate the presence of various underlying pathophysiological processes and patient subgroups. Objectives: We aimed to describe the characteristics of SEA and identify its patient subgroups. Methods: Clinical data from the Cohort for Reality and Evolution of Adult Asthma in Korea were analyzed. Cluster analysis was performed among those with SEA using 5 variables, namely, prebronchodilator forced expiratory volume in 1 s, body mass index, age at symptom onset, smoking amount, and blood eosinophil counts. Results: Patients with SEA showed prevalent sensitization to aeroallergens, decreased lung function, and poor asthma control status. Cluster analysis revealed 3 distinctive subgroups among patients with SEA. Cluster 1 (n = 177) consisted of patients reporting the lowest blood eosinophils (median, 346.8 cells/μL) and modest severe asthma with preserved lung function during the 12-month treatment period. Cluster 2 (n = 42) predominantly included smoking males with severe persistent airway obstruction and moderate eosinophilia (median, 451.8 cells/μL). Lastly, cluster 3 (n = 95) included patients with the most severe asthma, the highest eosinophil levels (median, 817.5 cells/μL), and good treatment response in terms of improved lung function and control status. Conclusions: Three subgroups were identified in SEA through the cluster analysis. The distinctive features of each cluster may help physicians predict patients who will respond to biologics with greater magnitude of clinical improvement. Further research regarding the underlying pathophysiology and clinical importance of each subgroup is warranted.
Abstract 10029: Near-Infrared Spectroscopy Assessments for the Prediction of Neurological Outcome in the Rat Model of Cardiac Arrest
Authors: Takegawa Ryosuke , Hayashida Kei , Miyara Santiago , Choudhary Rishabh , Khalili Houman , Endo Yusuke , Aoki Tomoaki , Shinozaki Koichiro , Becker Lance B
Published: December 2021

Introduction:
Clinical studies have demonstrated that the initial rapid decrement in regional cerebral oxygen saturation (rSO
2
) level by near-infrared spectroscopy shortly after ROSC was associated with good neurological outcomes.

Aim:
To evaluate whether the timing of rSO
2
decline shortly after ROSC reflects the severity of brain injury in a well-established rat model of CA/CPR.

Methods:
We used a total of 85 Wister SD rats (male, 435.2±3.1 g).To produce variable severities of brain injury, CA was induced by different asphyxial times and resuscitated by finger chest compressions and mechanical ventilation. Survival time was recorded for 72 hours after ROSC. Daily neurofunctional scores (NFS) were evaluated by an investigator blinded to the experiments. Electroencephalography (EEG), immunohistochemistry, plasma IL-6, and the gene expressions of cytokines (IL-1, IL-6, TNF-α, HMGB-1) and mitochondrial fission-related proteins (Dnm1L, Fis1, Mief1) in the brain were also evaluated.

Result:
Animals in the 12-min CA group exhibited a longer time to EEG recovery after CA/CPR compared with the 6-min group (P<.0001), suggesting the longer CA duration induces a delayed brain electrical recovery. Time from ROSC to achieving the initial minimum rSO
2
value (defined as T
nadir
) was significantly prolonged as CA time increased; 15.3 ± 2.3, 32.1 ± 22.1, and 44.0 ± 2.8 min in 6, 9, and 12min CA, respectively (ANOVA: P<.0001). T
nadir
cut-off of 24-min provided the optimal sensitivity and specificity for predicting good neurologic outcomes (NFS≥60%) at 72 hours after ROSC (AUC, 0.88; sensitivity, 89%; specificity, 86%; P<.01). T
nadir
showed a better predictive power for the good neurological outcome compared with plasma IL-6. Immunohistochemistry at 24 hours post-CA revealed that FJB-positive degenerating neurons in cortex, caudoputamen, and hippocampus were conspicuous in animals with T
nadir
>24-min, but not in animals with T
nadir
≤24-min. Animals with T
nadir
>24 tended to have a higher gene expression level of IL-6 in the brain at 2 hours post-ROSC compared to those with T
nadir
≤24. T
nadir
did not show associations with other inflammatory or mitochondrial fission markers.

Conclusion:
T
nadir
can be a novel predictor for a good neurological outcome after CA/CPR.
Abstract 10679: Tissue-to-Arterial Carbon Dioxide Partial Pressure Gradient as a Useful Measure for Monitoring Tissue Perfusion in a Pig Model of Hemorrhagic Shock and Resuscitation
Authors: Endo Yusuke , Becker Lance B , Takegawa Ryosuke , Miyara Santiago J , Molmenti Ernesto P , Hayashida Kei
Published: December 2021

Introduction:
Transcutaneous CO
2
(tcPCO
2
)

and arterial CO
2
(artPCO
2
) become decoupled during shock.

Aim:
To test the hypotheses the gradient between tcPCO
2
and artPCO
2
(tc-artPCO
2
)

can be an early, sensitive measure to detect inadequate tissue perfusion

in a pig model of hemorrhage shock.

Methods:
Six female pigs were used. A transcutaneous monitor was attached to the ear for measuring transcutaneous O
2
(tcPO
2
) and tcPCO
2
. Pulmonary artery catheter and the pulse index continuous cardiac output (PiCCO) were instrumented for monitoring a variety of hemodynamic parameters. To induce massive hemorrhagic shock, blood was withdrawn stepwisely. Then, animals were resuscitated in stages with transfusions of the stored blood. The parameters were measured at the timings of 10, 20, and 30 ml/kg of blood withdrawals and the completions of 10, 20, and 30 ml/kg of blood transfusion
.
Levels of systemic oxygen delivery (DO
2
) were also calculated at all measurement points.

Results:
Hemorrhage and blood transfusion impacted hemodynamic and laboratory data, such as cardiac output (CO), stroke volume, MAP, heart rate, pulmonary artery wedge pressure, global end-diastolic volume, hemoglobin, and arterial lactate. The tc-artPCO
2
markedly increased as CO decreased (
Figure A
). The critical level of DO
2
(DO
2crit
) was defined as 11.72 ml/kg/min according to tcPO
2
(a threshold as 30 mmHg). There was significant correlation between tc-artPCO
2
and DO
2
(r = -0.83, P<.0001). ROC analyses revealed that the AUCs to predict DO
2crit
for tc-artPCO
2
, shock index (SI), and lactate were 0.94 (95% CI, 0.87-1.00), 0.78 (0.63-0.93), and 0.65 (0.47-0.82), respectively. The AUC for tc-artPCO
2
was greater with respect to the prediction of DO
2crit
than for SI (P<.05) (
Figure B
).

Conclusions:
The tc-artPCO
2
strongly correlated with CO and DO
2
during hemorrhage shock and resuscitation. The less-invasive tc-artPCO
2
monitoring can sensitively detect systemic inadequate O2 supply in hemorrhagic shock.
Abstract 10739: Simulation Based Assessment of Trainee’s Performance in Post-Cardiac Arrest Resuscitation
Authors: Ali Afrah A , Chang Wan-Tsu , Tabatabai Ali , Pergakis Melissa B , Gutierrez Camilo A , Neustein Benjamin , Gilbert Gregory E , Podell Jamie E , Parikh Gunjan , Badjatia Neeraj , Motta Melissa , Lerner David P , Morris Nicholas A
Published: December 2021

Up to 22% of patients survive to hospital admission following out-of-hospital cardiac arrest (OHCA). Post cardiac arrest is complex and requires a multidisciplinary approach. Our aim is to assess trainee’s performance in managing post-cardiac arrest care using a high-fidelity manikin-based simulation. We also sought to obtain evidence regarding the validity of our findings.

Methods:
In this prospective, observational, simulation based study, participants ranging from sub interns to attending physicians evaluated and managed a post cardiac arrest patient, complicated by refractory status epilepticus. Critical actions were developed by a modified Delphi approach based on relevant American Heart Association guidelines and the Neurocritical Care Society’s Emergency Neurological Life Support protocols. The primary outcome measure was the critical action item sum score. We sought validity evidence to support our findings by comparing trainees’ performance across four levels of training.

Results:
Forty-nine participants completed the simulation. The mean sum of critical actions completed by participants was 10/21(49%). Eleven(22%) participants verbalized a differential diagnosis for the arrest. Thirty-two(65%) recognized the abnormal electrocardiography, and consulted cardiology. Forty trainees(81%) independently decided to start target temperature management (TTM), but only 20(41%) insisted on TTM when asked to reconsider. There was an effect of level of training on critical action checklist sum scores (novice mean score [standard deviation (SD)] = 4.8 (1.8) vs. intermediate mean score (SD) = 10.4 (2.1) vs. advanced mean score (SD) = 11.6 (3.0) vs. expert mean score (SD) = 14.7 (2.2)

Conclusions:
High-fidelity manikin-based simulation holds promise as an assessment tool in the performance of post-cardiac arrest care. Areas for further educational initiatives to improve performance include diagnostic work-up of OHCA and implementation of TTM.
Abstract 10874: Evaluation of Intensive Care Unit and Ventilator-free Days as Alternative Outcomes in Out-of-Hospital Cardiac Arrest Trials
Authors: Wang Henry E , Panchal Ashish R , Nassal Michelle , Vanden hoek Terry , Li Jing , CALLAWAY Clifton W , Nichol Graham , Daya Mohamud R , Schmicker Robert , Idris Ahamed , Aufderheide Tom P , Hansen Matthew L , Hyer Madison , Wei Lai
Published: December 2021

Objective:
Compared with traditional out-of-hospital cardiac arrest (OHCA) trial outcomes such as hospital survival, alternative outcomes such as intensive care unit-free (IFD) and ventilator-free days (VFD) have potential advantages including requiring smaller sample sizes to detect significant differences. Few studies have evaluated these outcomes in OHCA. We sought to evaluate the utility and validity of IFD and VFD as candidate outcomes for OHCA trials.

Methods:
We analyzed data from the Pragmatic Airway Resuscitation Trial (PART), which tested laryngeal tube (LT) vs. endotracheal intubation (ETI) airway strategies in adult OHCA. We defined IFD as the number of days alive and permanently out of ICU during the first 30 days after the OHCA event. We examined IFD distribution and correlation with Modified Rankin Scale (MRS). To test associations with trial interventions, we applied a range of analytic strategies, including modeling IFD as continuous (Generalized Estimating Equations - GEE), non-parametric (Wilcoxon Rank-Sum test - WRS) and count (zero-inflated negative binomial regression - ZINB) data. We also modeled time-to-ICU discharge using a survival model with death as a competing risk. We repeated the analysis assessing VFD.

Results:
IFD was available for 2,898 of 3,004 patients. IFD was skewed and J-shaped; 91% IFD=0 and 5.3% IFD≥22. Mean (±SD) IFD was 2.0±6.6 days; 21.2±7.5 days for survivors. IFD varied by intervention (LT 2.4±7.2, ETI 1.6±5.8 days). IFD and VFD strongly correlated with MRS (ρ= -0.88, -0.89). LT was associated with increased IFD using GEE, WRS, and ZINB, but not competing risks model. (Table) LT was associated with increased VFD using GEE and WRS, but not ZINB or competing risks models.

Conclusion:
IFD and VFD differentiated OHCA interventions, suggesting their utility. IFD and VFD were highly correlated with MRS, suggesting validity. IFD and VFD have important features that may influence OHCA trial design.
Abstract 10936: Gender Disparities in In-Hospital Management of Out-of-Hospital Cardiac Arrest Patients: A Propensity Score Matching Analysis
Authors: Kim Jooyeong , Sung Jin Kim , Ahn Sejoong , Park Jonghak , Song Juhyun , Cho Hanjin
Published: December 2021

Background:
Gender differences of outcomes of out-of-hospital cardiac arrest (OHCA) were reported in previous studies and still remains uncertainty. Furthermore, gender disparities in in-hospital management are not well studied.

Hypothesis:
We hypothesized there is differences in in-hospital management in OHCA patients by gender in Korea.

Method:
This is an observational study using Korean Cardiac Arrest Research Consortium (KoCARC) data. Adult (age over 18 years) OHCA patients from October 2015 to June 2020 were included. The main variable of interest was gender. Primary outcomes were whether in-hospital managements such as coronary angiography (CAG), percutaneous coronary intervention (PCI), target temperature management (TTM), and extracorporeal membrane oxygenation (ECMO) were performed. Secondary outcomes were clinical outcomes such as survival to admission, survival to discharge, and good neurologic outcome (cerebral performance category 1 or 2) at discharge. The propensity score matching (PSM) method was performed to minimize differences in baselines demographics and characteristics.

Results:
Total 8,177 OHCA patients were enrolled. After PSM, 6564 patients (female: 2782, male: 2782) were obtained. In unmatched cohort, female patients were less likely receive CAG, PCI, TTM, ECMO and less likely to survive to admit, survive to discharge, and discharge as good neurologic outcome. In PSM cohort, female patients were less likely to receive CAG, PCI than male (179 (6.4%) vs 252 (9.1%), p<0.001 and 54 (1.9%) vs 104 (8.2%), p<0.001, respectively). The proportion of TTM, ECMO, and clinical outcomes were not statistically different among gender.

Conclusions:
CAG, PCI were less likely to performed in female OHCA patients. Further studies are needed for gender disparities in in-hospital management of OHCA patients.
Abstract 11045: Pre-Hospital Airway for Out-of-Hospital Cardiac Arrest: A Nationwide Multicenter Study
Authors: Chang Hansol , Choi Jin Ho , JEONG DAUN
Published: December 2021

Introduction:
This study investigated whether use of pre-hospital advanced airway management (AAM) is associated with improved survival of adults with out-of hospital cardiac arrest (OHCA) compared to conventional bag-valve-mask ventilation (BVM).

Method:
The study subjects were derived from Korean Cardiac Arrest Research Consortium (KoCARC), a multi-center OHCA registry of Korea. Patients who underwent AAM or BVM using supraglottic airway, oropharyngeal airway, or endotracheal intubation were compared. The differences in baseline clinical characteristics were adjusted using propensity scoring matching (PSM) or inverse probability of treatment weighting (IPTW). The primary outcome was 30-day survival with neurologically favorable status of cerebral performance category ≤2. The outcome was also compared according to the duration of low-flow time.

Results:
Of 9,616 patients enrolled, (median age = 71, male sex = 65%) there were 7,583 AAM and 2,033 BVM patients. The unadjusted survival to with neurologically favorable status was lower in AAM compared to BVM (HR = 1.27, 95% confidence interval (CI) = 1.20 - 1.34, p<0.001). However, there was no significant difference of survival to with neurologically favorable status between AAM and BVM after PSM or ITPW-adjusted comparisons (p>0.05, all). This finding was consistent irrespective of duration of low-flow time.

Conclusion:
In this nationwide real-world data of out-of hospital cardiac arrest study, prehospital advanced airway management compared to bag-and-mask ventilation did not result in an improved clinical outcome at 30 days.
Abstract 11112: Impact of Changes in Clinical Practice Guidelines on Survival Outcomes After Traumatic Out-of-Hospital Cardiac Arrest
Authors: Alqudah Zainab , Nehme Ziad , Williams Brett , Oteir Alaa , Smith Karen L
Published: December 2021

Aim:
In this study, we examine the impact of a trauma-based resuscitation protocol on survival outcomes following emergency medical services (EMS) witnessed traumatic out-of-hospital cardiac arrest (OHCA).

Methods:
We included EMS-witnessed OHCAs arising from trauma and occurring between 2008 and 2019. In December 2016, a new resuscitation protocol for traumatic OHCA was introduced prioritizing the treatment of potentially reversible causes before conventional cardiopulmonary resuscitation. The effect of the new protocol on survival outcomes was assessed using adjusted multivariable logistic regression models.

Results:
Paramedics attempted resuscitation on 490 patients, with 341 (69.6%) and 149 (30.4%) occurring during the control and intervention periods, respectively. A reduction in the proportion of cases receiving cardiopulmonary resuscitation and epinephrine administration were found in the intervention period compared to the control period, whereas trauma-based interventions increased significantly, including blood administration (pre-arrest: 17.9% vs 3.7%; intra-arrest: 24.1% vs 2.7%), splinting (pre-arrest: 38.6% vs 17.1%; intra-arrest: 20.7% vs 5.2%), and finger thoracostomy (pre-arrest: 13.1% vs 0.6%; intra-arrest: 22.8% vs 0.9%), respectively, with p-values <0.001 for all comparisons. After adjustment, the trauma-based resuscitation protocol was not associated with an improvement in survival to hospital discharge (AOR 1.29, 95% CI: 0.51-3.23), event survival (AOR 0.72, 95% CI: 0.41-1.28) or prehospital return of spontaneous circulation (AOR 0.63, 95% CI: 0.39-1.03).

Conclusion:
In our region, the introduction of a trauma-based resuscitation protocol led to an increase in the delivery of almost all trauma interventions; however, this did not translate into better survival outcomes following EMS-witnessed traumatic OHCA.
Abstract 11488: Ventilation Rate and Sustained Return of Spontaneous Circulation in In-Hospital Cardiac Arrest: Is More Better?
Authors: Jaffe Ian S , Yuriditsky Eugene , Keshavarz Shirazi Tara , Gonzales Anelly , Horowitz James , Parnia Sam
Published: December 2021

Introduction:
Current consensus holds that CPR must balance chest compressions and ventilation rate (VR), with a low VR being essential for venous return and cardiac output. AHA guidelines recommend a VR of 10 ventilations per minute (vpm) after advanced airway placement. We sought to examine VR adherence and its impact on end-tidal CO
2
(ETCO
2
) and ROSC >20 minutes.

Methods:
This is a retrospective analysis of data from AWARE II, a multicenter prospective observational study of adult in-hospital cardiac arrest (IHCA) outcomes at 14 US and UK sites. Inclusion criteria were: 1) adult patient in CA, 2) advanced airway already in place or placed during the CA, and 3) at least one minute of VR and ETCO
2
data available after removal of the last minute of CPR in subjects achieving ROSC (due to the rise of ETCO
2
just prior to ROSC).

Results:
A total of 563 subjects were enrolled in the parent study. Of these, 225 had ETCO
2
and VR tracings available, and 201 had sufficient data for inclusion. Mean age was 69.3 (range 18-100), patients were 63.7% male, and 16.4% had a shockable initial rhythm. A total of 116 subjects (57.7%) achieved ROSC, which was sustained in 76 (37.8%), leading to survival to hospital discharge with favorable neurological outcomes in 9 (4.5%). Mean VR was 16.3 vpm, with 171 (85.1%) subjects being ventilated in excess of guidelines; only 16 (8.0%) subjects received 8-10 vpm. Higher VR had a weak but significant association with increased mean ETCO
2
(linear R
2
= 0.11, p < 1x10
-6
) and sustained ROSC (OR 1.05; 95% CI: 1.01-1.11; p = 0.02). Patients with sustained ROSC had a significantly higher VR at 17.7 vpm than those without sustained ROSC at 15.6 vpm (p = 0.007). Patients receiving a VR close to AHA guidelines (6-12 vpm) had a significantly lower rate of sustained ROSC (26.1%, n = 46) than patients receiving >12 vpm (42.0%, n = 148) (OR 2.30; 95% CI: 1.08-4.89; p = 0.031 using a multivariate model including patient age, shockable initial rhythm, known cardiac disease, witnessed IHCA, and use of mechanical compressions).

Conclusions:
VR within AHA guidelines is rare during IHCA. However, ventilation in excess of current guidelines may increase rates of sustained ROSC, an essential predicate to survival. AHA guidelines on VR in CPR with an advanced airway may not yet be optimized.
Abstract 11652: Long-Term Outcomes in Post-Cardiac Arrest Patients With Severe Functional Disability at Hospital Discharge
Authors: Xiao Amy , Coppler Patrick J , CALLAWAY Clifton W
Published: December 2021

Background:
In patients resuscitated from out of hospital cardiac arrest (OHCA) with severe functional disability, life support is often limited. However, long-term outcomes in such patients are largely unknown, leaving little data to guide this decision.

Methods:
We performed a retrospective cohort study of OHCA survivors ≥ 18 years of age, treated at a single center in Western Pennsylvania from 01/01/2010-05/20/2021, with a modified Rankin scale (mRS) of 5 and cerebral performance category (CPC) of 4 at hospital discharge. We recorded demographics, arrest characteristics, and neurological exam at hospital discharge. We reviewed records from index hospitalization to the present to determine the date and type of subsequent healthcare encounters and whether or not subjects followed commands in subsequent neurological exams. National Death Index query and internet search for obituary until 5/20/2021. Survival time and hazard ratios were estimated using Kaplan-Meier curves.

Results:
Among 2,460 OHCA patients treated, 857 (35%) survived to hospital discharge. Of survivors, 83 (9.6%) had mRS 5 and CPC 4, and 69 (85%) did not follow commands. One year mortality was 59% (n=48) with median survival time of 166 days (IQR 77-1083). Age ≥ 65 years was not associated with survival [HR 1.51, 95%CI 0.79 - 2.89]. We found 361 subsequent medical encounters (median per patient =1, IQR 0-4), most often ED visits (n=131, 41%). Visits comprised 87 (28%) well patient visit/medication refills, 60 (22%) infections, and 38 (12%) tracheostomy/feeding tube issues. Average frequency of healthcare encounters was about once every 3 months (.30 encounters per month, SD .799). Of subjects who did not follow commands at hospital discharge, 4 (6%) followed commands on subsequent encounters.

Conclusions:
About 10% of OHCA survivors were discharged from the hospital with severe functional disability. They had a 59% 1-year mortality and frequent visits to the ED. Few (6%) patients regained the ability to follow commands.