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ABSTRACT Background Methods Results Conclusions Cryoballoon ablation has been widely performed in patients with paroxysmal atrial fibrillation (AF). In some challenging pulmonary veins (PVs), the procedure requires additional touch‐up applications against the residual conduction gaps. It implies that there could exist difficult sites to cover with standard cryoballoon applications (CBAs), resulting in resistant conduction gaps (RCGs). This study aims to characterize the RCGs after initial CBAs.We retrospectively enrolled 90 consecutive paroxysmal AF patients in our institute from January 2018 to December 2021 (66.5 ± 8.9 [SD] year‐old, male/female 58/32). The RCGs after initial CBAs were mapped and analyzed with a high‐resolution mapping (HRM) catheter. The PVs isolated using HRM were classified as HRM group. The PVs isolated without HRM, if isolated with a total of one or two CBAs, were classified as Control group.Whereas 325 PVs were isolated without HRM, 29 PVs had RCGs which were mapped and identified with HRM (HRM group): 15 right inferior pulmonary veins (RIPVs), 11 left superior PVs (LSPVs), and 3 left inferior PVs (LIPVs). In HRM group, the rate of broad RCGs in each PV extending over 2 or 3 segments of PV was almost double that of one‐segment RCGs. The width of RCGs significantly correlated with nadir balloon temperature (R = 0.42; p = 0.021) and iTT15 (R = −0.44; p = 0.015).After standard CBAs, most RCGs were demonstrated to spread from the bottom to the posterior wall of RIPV and from the roof to the anterior wall of LSPV. The width of the RCGs was found to be correlated with parameters of balloon temperature, such as Tnadir and iTT15. [ABSTRACT FROM AUTHOR]

Background: The innovative peak frequency mapping facilitates the quantification of electrogram sharpness. However, reference values for normal atrial tissue are currently undefined. In this study, we explored the distribution of peak frequency and omnipolar peak-to-peak voltage (V-max) in a normal heart. Methods: Twenty-two patients with structurally normal heart were included. Either the right atrium (RA) and superior vena cava (SVC) or the left atrium (LA) and pulmonary veins (PVs) were mapped during sinus rhythm. Results: In total, 13,654 points in the RA and 4143 points in the SVC from 15 patients and 4662 points in the LA and 2761 points in PVs from 7 patients were analyzed. The correlation between peak frequency and V-max was weak (R = 0.223). The median peak frequency was larger in the SVC than in the RA (441 [358–524] Hz vs. 358 [291–441] Hz, P < 0.0001) and in PVs than in the LA (346 [253–441] Hz vs. 323 [262–397] Hz, P < 0.0001). Conversely, the median V-max was smaller in the SVC than in the RA (1.96 [0.77–3.75] mV vs. 4.11 [2.10–6.83] mV, P < 0.0001) and in PVs than in the LA (1.16 [0.33–3.17] mV vs. 4.42 [2.63–6.84] mV, P < 0.0001). More than 95% of peak frequencies were > 174 Hz in the RA and > 185 Hz in the LA, and > 95% of V-maxes were > 0.52 and > 1.07 mV in the RA and LA, respectively. Conclusion: Given the limited correlation between peak frequency and V-max, and recognizing their potential to provide distinct information, they can be used complementarily. Employing these parameters to extract varied insights can provide comprehensive understandings of tissue characteristics. [ABSTRACT FROM AUTHOR]

A 53-year-old patient with a history of heart transplant is referred for atrial tachycardia ablation. Two dissociated concomitant rhythms are observed: a focal atrial tachycardia in the donor atrium and atrial fibrillation in the remaining recipient atrium.

Mangroves are one coastal ecosystem that has experienced a long history of fragmentation and loss by urbanization. Yet, these small mangroves in urban areas are often missing from current wetland inventory due to lower resolution mapping methods and size classifications that may overlook these mangroves in highly urbanized areas. We mapped mangroves along a gradient of urbanization in Miami-Dade County, Florida (MDC) by combining several landcover databases, high-resolution imagery, and ground-truthing. We compared our newly mapped mangrove dataset with the Florida Fish and Wildlife Conservation Commission’s (FWC) current mangrove habitat dataset. We quantified differences in mangrove area, fragmentation metrics, and shape complexity across three urban intensities within MDC and between the datasets. We identified an additional 386 mangrove patches that were missed by the FWC map. The majority of these newly found mangroves were in the most urban regions of MDC. We identified average mangrove stand size in the least urbanized region is about 29 times bigger than those found in the most urbanized region. We also found that the FWC dataset significantly overestimated average mangrove stand size (18.32-ha) compared to the newly mapped mangrove dataset (1.43-ha) in the most urbanized region. Our results demonstrate that large scale wetland mapping efforts, like those of state agencies, provide valuable mangrove area estimations but may miss key fragmentation patterns by not including smaller mangrove stands scattered throughout highly urbanized regions. Habitat maps that capture these smaller, fragmented mangroves are needed to evaluate how urbanization shapes mangrove extent and ecosystem function. [ABSTRACT FROM AUTHOR]

Idiopathic verapamil‐sensitive fascicular ventricular tachycardia (VT) is the most common form of Purkinje‐related ventricular tachycardia (PRVT). Left septal fascicle (LSF) involvement and its connections with the other fascicles, have been recently reported as a pathophysiologic mechanism for this form of PRVT. We describe a case of idiopathic PRVT with LSF involvement using omnipolar technology (OT) mapping in relation to a false tendon. Ablation in the area with concealed fusion entrainment did not terminate the tachycardia. However, radiofrequency application in the area of LSF with manifest fusion entrainment, resulted in immediate tachycardia termination. Six months follow‐up showed no tachycardia recurrence. [ABSTRACT FROM AUTHOR]

An accurate and timely spatialization of electricity consumption is fundamental for energy management and sustainable urban development. While previous research has relied heavily on statistical data or moderate-resolution nighttime light data, this study has presented a new spatialization method by combining high-resolution Luojia 1–01 nighttime light and urban functional zoning information. The total electricity consumption volume can be allocated to each land use pixel based on its strong linear relationship with nighttime light. Specifically, urban functional zoning data were connected with the corresponding economic sectors to differentiate the complex relationships between electricity consumption and nighttime light within different zones. The digital number value of every pixel can be multiplied by its corresponding electricity consumption coefficient. A number of comparisons have indicated that the proposed method can more accurately characterize the spatial distribution of electricity consumption. Our results can exhibit much clearer outlines and more detailed internal characteristics. More importantly, urban functional zoning information can be used to distinguish the electricity consumption of various economic sectors at fine scales. The proposed method is expected to capture the spatial characteristics of electricity consumption in a timely and accurate manner. The findings can help local authorities formulate sustainable energy utilization and emission reduction strategies.

Numerous studies estimating transport CO2 emissions in developing countries were on the large scales and few provided high-resolution mapping of transport CO2 emissions from different transport modes according to their respective distribution and diffusion patterns. This study proposed a hybrid method for high-resolution mapping of transport CO2 emissions in metropolitan regions, and applied it to the Beijing–Tianjin–Hebei (BTH) region of China during 2000-2019. The results indicate that: (1) The transport CO2 emissions in the BTH region increased rapidly, of which road transport carbon emissions accounting for approximately 80%, air transport carbon emissions accounting for nearly 20%, railway and water transport accounted for a relatively small proportion. (2) For the transport CO2 emission structure from 2000 to 2019, road transport was still the main source, but its proportion has decreased since recent years, which air transport became the second largest source of emissions and had greater impact on Beijing and Tianjin. (3) The transport carbon emission hot spots were mainly located in Beijing and kept shrinking, while the cold spots were mainly located in the southern part of Hebei Province and kept expanding. (4) The decoupling relationship between county-level transport carbon emissions and economic growth changed from weak decoupling to expansive negative decoupling, showing a non-ideal development in the BTH region. Overall, this study revealed the spatiotemporal characteristics of transport CO2 emissions in the BTH region, based on which specific carbon reduction strategies could be promoted to facilitate sustainable low-carbon transport development in metropolitan regions in developing countries. [ABSTRACT FROM AUTHOR]

In urban areas, human exposure to environmental pollution is a major concern for health and well-being. It is yet unclear which existing pollution is actually perceived by the residents. This study contributes to a combined analysis of measured and perceived environmental pressures. Based on a high-resolution land cover mapping using the object-based image approach, urban structural information is obtained. Then, a heterogeneous urban district is selected for in-depth investigation to find out if there is a correlation between building structures and exposition. The environmental pressures on urban dwellers are investigated here on a refined scale with mobile measurements and accompanied by walking interviews. Measurements on noise, PM2.5, PM10, and high air temperatures are taken twice a day to monitor potential differences between the early morning and the afternoon situations and how big these might be. The results give a multifaceted picture of the measured and perceived influences. Noise is simply accepted by most interlocutors, as traffic is seen as a fact of life. The perception of measured air temperature varies greatly between pleasant and burdensome, where more stressful situations seem to occur in linear housing and some family homes with either little green infrastructure or a monotonous pattern of large meadows. Most strikingly are the measured PM ranges, where PM2.5 can reach very high values, twice that of PM10. Although PM2.5 severely affects the respiratory system, there is little awareness of these effects. Raising environmental awareness is crucial for environmental health and connects researchers and planners.

High-resolution spatial distribution maps of GDP are essential for accurately analyzing economic development, industrial layout, and urbanization processes. However, the currently accessible GDP gridded datasets are limited in number and resolution. Furthermore, high-resolution GDP mapping remains a challenge due to the complex sectoral structure of GDP, which encompasses agriculture, industry, and services. Meanwhile, multi-source data with high spatial resolution can effectively reflect the level of regional economic development. Therefore, we propose a multi-scale fusion residual network (Res-FuseNet) designed to estimate the GDP grid density by integrating remote sensing and POI data. Specifically, Res-FuseNet extracts multi-scale features of remote sensing and POI data relevant to different sectors. It constructs a joint representation of multi-source data through a fusion mechanism and accurately estimates GDP grid density for three sectors using residual connections. Subsequently, the high-resolution GDP grid data are obtained by correcting and overlaying grid density for each sector using county-level statistical GDP data. The 100-meter gridded GDP map of the urban agglomeration in the middle reaches of the Yangtze River in 2020 was successfully generated using this method. The experimental results confirm that Res-FuseNet outperforms machine learning models and baseline model significantly in training across different sectors and at the town-level. The R2 values for the three sectors are 0.69, 0.91, and 0.99, respectively, while the town-level evaluation results also exhibit high accuracy (R2=0.75). Res-FuseNet provides an innovative high-resolution mapping method, and the generated high-resolution GDP grid data reveal the distribution characteristics of different sector structures and fine-scale economic disparities within cities, offering robust support for sustainable development.

BACKGROUND: Abnormal atrial potentials (AAPs) recorded during sinus rhythm/atrial pacing may indicate areas of slow conduction capable of supporting reentrant atrial tachycardia (AT). Therefore, we sought to examine the relationship between AAPs and AT circuits. METHODS: One hundred twenty-three reentrant ATs in 104 patients were analyzed. AAPs, consisting of fragmented potentials and split potentials, were assessed using the Rhythmia LUMIPOINT algorithm. RESULTS: There was 93±13% overlap between areas with AAPs during sinus rhythm/atrial pacing and areas of slow conduction along the reentry circuit during AT. The cumulative area of AAPs was smaller in patients with localized-reentrant ATs compared with anatomic macro-reentrant ATs (20.0 [14.6-30.5] versus 28.9 [21.8-35.6] cm2; P=0.021). Patients with perimitral ATs had larger areas of AAPs on the lateral wall whereas patients with roof-dependent ATs had larger areas of AAPs on the roof and posterior wall (P=0.018 for all comparisons). The patchy scar that was associated with localizedreentrant AT exhibited a larger area of AAPs at its periphery than the scar that did not participate in localized-reentrant AT (3.1 [2.4-4.5] versus 1.0 [0.7-1.6] cm2; P<0.001). CONCLUSIONS: AAPs recorded during sinus rhythm/atrial pacing are associated with areas of slow conduction during reentrant AT. The burden and distribution of AAPs may provide actionable insights into AT circuit features, including in cases in which ATs are difficult to map. [ABSTRACT FROM AUTHOR]

Reliable and detailed information on livestock distribution is essential for studies of food security, environmental change, and even sustainable development. However, insufficient accuracy and inadequate validation currently remain in high-resolution livestock distribution datasets primarily resulting from using spatially-continuous models and deficient data. This study presents, for the first time to our knowledge, a spatially detailed dataset on intensive (point) and extensive (30”× 30” grid) livestock production in China (HIEL-China) in 2017 based on an improved model and multi-scale data. Technical validation shows high accuracy in spatial distribution and farm-size simulation. Based on the more reliable depiction of livestock farms, we addressed the obvious underestimation of livestock density in previous datasets, and found different structures of livestock production systems in urban, peri-urban and rural areas. This study accordingly contributes to an essential data basis for livestock-associated analyses targeting at sustainable development of food systems, especially for the largest contributor to global livestock production.

Hydroacoustic surveys at the accretionary wedge southwest of Taiwan reveal a confined active hydrocarbon seepage area of ~ 49,000 m2 in ~ 1350 m water depth on the northern crest of the Four-Way Closure Ridge, which we call Yam Seep. In this study, multibeam and side-scan sonar data acquired during surveys with an autonomous underwater vehicle during an expedition with R/V Ocean Researcher I in 2017 showed that the area is characterized by rough topography and high seafloor backscatter. Seafloor observations with a video sled and sediment sampling with gravity corers and the MeBo seafloor drill rig during an expedition with R/V SONNE in 2018 revealed that the area is almost entirely covered by intensely fractured methane-derived carbonates, which indicate that seepage has been ongoing for thousands of years. Hydroacoustic anomalies ('flares') in the water column indicated the presence of several gas bubble emission sites mostly at the center and eastern flank of the area in 2019. Drilling through massive carbonates in the northwestern part of Yam Seep induced free gas escape from a depth of ~ 5.1 m. This suggests the presence of gas hydrates in the subsurface as the seep area is located well within the gas hydrate stability zone. The inter-disciplinary investigations of the Yam Seep demonstrate that upward migration of light hydrocarbons and seafloor discharge has a considerable influence on the seabed properties. [ABSTRACT FROM AUTHOR]

Abstract Background Cutaneous electrogastrography (EGG) is a non-invasive technique that detects gastric bioelectrical slow waves, which in part govern the motility of the stomach. Changes in gastric slow waves have been associated with a number of functional gastric disorders, but to date accurate detection from the body-surface has been limited due to the low signal-to-noise ratio. The main aim of this study was to develop a flexible active-electrode EGG array. Methods: Two Texas Instruments CMOS operational amplifiers: OPA2325 and TLC272BID, were benchtop tested and embedded in a flexible linear array of EGG electrodes, which contained four recording electrodes at 20-mm intervals. The cutaneous EGG arrays were validated in ten weaner pigs using simultaneous body-surface and serosal recordings, using the Cyton biosensing board and ActiveTwo acquisition systems. The serosal recordings were taken using a passive electrode array via surgical access to the stomach. Signals were filtered and compared in terms of frequency, amplitude, and phase-shift based on the classification of propagation direction from the serosal recordings. Results: The data were compared over 709 cycles of slow waves, with both active cutaneous EGG arrays demonstrating comparable performance. There was an agreement between frequencies of the cutaneous EGG and serosal recordings (3.01 ± 0.03 vs 3.03 ± 0.05 cycles per minute; p = 0.75). The cutaneous EGG also demonstrated a reduction in amplitude during abnormal propagation of gastric slow waves (310 ± 50 µV vs 277 ± 9 µV; p

A 77-year-old man underwent radiofrequency catheter ablation of incessant ventricular arrhythmias (VAs) originating from the right ventricular (RV) moderator band (MB). Activation mapping during the VAs exhibited a centrifugal pattern with the earliest activation site (EAS) on the RV septum. A local impedance (LI)-guided radiofrequency application targeting the EAS with a maximum power output of 50W successfully eliminated the VAs and resulted in an LI drop of up to 35 Ω. Late gadolinium enhancement magnetic resonance imaging (LGE-MRI) on the day after the ablation procedure demonstrated a confluent non-enhanced dark core on the RV septal portion of the MB. On the LGE-MRI two months after the procedure, the dark core region became contracted and instead the peripheral region surrounding the dark core exhibited a bright enhancement. The size of the dark core and peripheral enhanced regions on the LGE-MRI remained almost unchanged two months to two years after the procedure. He had no VA recurrences during a two-year follow-up period. Previous LGE-MRI studies reported that an ablated area within healthy ventricular myocardium exhibits a bright homogenous enhancement during the post-ablation chronic phase, while that within ventricular scar tissue exhibits a confluent non-enhanced dark core. This case suggested the presence of a dark core with a peripheral enhancement corresponding to the ablated area within the healthy myocardium of the RV-MB. LGE-MRI may be useful for accurately detecting RF ablation lesions on the RV-MB and visualizing the serial changes in the LGE-MRI characteristics from the post-ablation acute to chronic phases.

Structure-from-Motion (SfM) photogrammetry is a time and cost-effective method for high-resolution 3D mapping of cold-water corals (CWC) reefs and deep-water environments. The accurate classification and analysis of marine habitats in 3D provide valuable information for the development of management strategies for large areas at various spatial and temporal scales. Given the amount of data derived from SfM data sources such as Remotely-Operated Vehicles (ROV), there is an increasing need to advance towards automatic and semiautomatic classification approaches. However, the lack of training data, benchmark datasets for CWC environments and processing resources are a bottleneck for the development of classification frameworks. In this study, machine learning (ML) methods and SfM-derived 3D data were combined to develop a novel multiclass classification workflow for CWC reefs in deep-water environments. The Piddington Mound area, southwest of Ireland, was selected for 3D reconstruction from high-definition video data acquired with an ROV. Six ML algorithms, namely: Support Vector Machines, Random Forests, Gradient Boosting Trees, k-Nearest Neighbours, Logistic Regression and Multilayer Perceptron, were trained in two datasets of different sizes (1,000 samples and 10,000 samples) in order to evaluate accuracy variation between approaches in relation to the number of samples. The Piddington Mound was classified into four classes: live coral framework, dead coral framework, coral rubble and sediment and dropstones. Parameter optimisation was performed with grid search and cross-validation. Run times were measured to evaluate the trade-off between processing time and accuracy. In total, eighteen variations of ML algorithms were created and tested. The results show that four algorithms yielded f1-scores >90% and were able to discern between the four classes, especially those with usually similar characteristics, e.g., coral rubble and dead coral. The accuracy variation among them was 3.6% which suggests that they can be used interchangeably depending on the classification task. Furthermore, results on sample size variations show that certain algorithms benefit more from larger datasets whilst others showed discrete accuracy variations (

Background: Although differential pacing conventionally has been used to confirm the achievement of block across linear lesion sets, high-resolution mapping demonstrates that pseudo-block is observed in 20%-30% of cases.Objectives: The purpose of this study was to examine the reliability and versatility of a method using "activation vectors" based on omnipolar technology to confirm the block line.Methods: Linear ablation was performed during pacing, with the HD Grid catheter (Abbott) placed beside the linear lesion opposite the pacing site. The endpoint of complete linear lesion was complete inversion of the activation vectors to the opposite direction. When inversion of the activation vectors was not observed after 10 minutes of radiofrequency (RF) application, high-resolution mapping was performed to assess whether complete block was achieved.Results: In 33 patients, 24 cavotricuspid isthmus lines, 11 mitral isthmus (MI) lines, 16 posterior lines, and 2 intercaval lines were performed using this method. Of the total of 53 lines, 10 (18.9%) required intermediate evaluation of the block line with high-resolution mapping because of the absence of inversion of activation vectors despite 10 minutes of RF application, resulting in incomplete block with endocardial gaps or epicardial conductions. Additional RF applications finally achieved inversion in direction of activation vectors in the 10 lines. In total, the present method can diagnose achievement of complete block line with 100% accuracy, whereas conventional differential pacing misdiagnosed incomplete block with epicardial conduction in posterior lines in 3 cases and in MI lines in 2 cases.Conclusion: Confirmation of complete linear lesions using "activation vectors" based on omnipolar technology is a reliable and versatile method. [ABSTRACT FROM AUTHOR]

Background: An acute cryothermal ablation lesion contains both reversible and irreversible elements. However, differences in lesions created with cryoballoon pulmonary vein isolation (PVI) between the acute and chronic phases have not been fully elucidated. Methods: We retrospectively analyzed 23 consecutive patients with atrial fibrillation who underwent cryoballoon PVI during the initial procedure followed by a second ablation procedure. In all patients, cryoballoon PVI lesions were evaluated with high-resolution voltage mapping just after PVI (acute phase) and during the second session (chronic phase). We compared the area and width of the non-isolated left atrial posterior wall (NI-LAPW) with voltage ≥ 0.5 mV during both sessions. Results: PVI was successfully achieved in all patients. Cryoballoon PVI lesions were re-evaluated at 11 [2–17] months post-procedure. During the chronic phase, NI-LAPW width became significantly larger at the level of the roof (change, 5.8 ± 5.5 mm; p < 0.001) and at the level of the carina (change, 3.3 ± 7.0 mm; p < 0.05), and NI-LAPW area became significantly larger (change, 1.5 ± 1.9 cm2; p < 0.001) compared with the acute phase. Eight patients without any PV reconnections also had larger NI-LAPW areas (change, 1.3 ± 1.2 cm2; p < 0.05) during the chronic phase. Conduction resumption confined to the right carina was observed in 1 (4.3%) patient who presented with circumferential PVI that included the carina during the first session. Conclusion: Acute cryoballoon PVI lesions significantly regressed during the chronic phase. PV reconnections and the isolation area should be carefully re-evaluated during the second procedure. [ABSTRACT FROM AUTHOR]

Cities, contributing over 70% of global emissions, are key areas for climate change mitigation. Heterogeneity within cities determines the need for spatialized urban emissions reduction policies. However, few studies have attempted to characterize the spatial distribution of carbon emissions at the urban scale. To address this issue, a novel mapping method was proposed, using Xi'an as an example to explore the spatial distribution of carbon emissions at the city scale. Firstly, multiple geospatial open-source data, such as point of interest (POI), road networks, and land use, were utilized to identify the locations of emission sources. High-resolution carbon emission distributions were then mapped by allocating emissions based on the Intergovernmental Panel on Climate Change (IPCC) methodology. The study employed Global Moran's I to analyze the changes in spatial heterogeneity at different resolutions. Additionally, the Local Indicators of Spatial Association index (LISA) and Standard Deviation Ellipses (SDE) were adopted to examine the spatiotemporal characteristics of carbon emissions in Xi'an. The results show that carbon emissions at Xi'an City rises from 45.112 million tons to 72.701 million tons between 2010 and 2021. The construction of multi-scale carbon emissions spatial distributions, with a resolution of up to 30 m, allowed for a more detailed characterization of carbon emissions, especially in urban fringe areas. In addition, the results indicate that urban carbon emissions exhibit the strongest spatial autocorrelation at a resolution of 350 m. The study can provide a reference for the development of regional carbon emission reduction policies and spatial planning. In addition, the proposed spatialized method of city carbon emissions depends on open-source data, which allows it to have the potential for application in other cities. [Display omitted] • Carbon emissions at Xi'an City rises from 45.112 to 72.701 Mt tons between 2010 and 2021. • A new 30 m resolution method for mapping carbon emissions is proposed. • City carbon emissions exhibit the strongest spatial autocorrelation at a resolution of 350 m. [ABSTRACT FROM AUTHOR]

A combined laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and energy dispersive X-ray spectroscopy (EDS) study was used to map 49 elements in four Fe Mn precipitates produced from three different genetic processes (hydrogenetic, hydrothermal, and mixed-type hydrogenetic-hydrothermal) in samples obtained from the southern Mariana Arc. Results show Mn-oxide minerals are consistently found to be associated with Ba, Mo, Sb, V, Zn, and the rare earth elements and yttrium (REY), excluding Ce, whereas Fe-oxyhydroxide minerals are primarily associated with Ti, Co, Cr, Cu, Nb, and Pb. Element distributions in Fe Mn precipitates from the southern Mariana Arc differ from deposits formed in other environments; notably, there is a decoupling of As and Sb, and redox-sensitive elements are more variable than non-redox-sensitive elements. Samples previously classified as either hydrogenetic or hydrothermal in origin, based on bulk geochemical data, show characteristics of both at higher resolution. Combining high resolution in-situ data with genetic classification discrimination diagrams reveals more ambiguity in metal and metalloid origin than previously thought. Mariana Arc Fe Mn precipitates can be separated into two formation sub-types (hydrothermal or mixed hydrothermal/hydrogenetic) based on textural and compositional differences, e.g., differences in Ce/Ce and Y/Ho values and relative variations in (Zr + Y + Ce) versus (Co + Ni) versus (Mn + Fe). Improved classification and knowledge of how fast-growing hydrothermal Fe Mn precipitates form may help us identify a relatively renewable critical metal resource. [Display omitted] • High resolution laser ablation maps (∼ 1 mm2) were constructed from Mn crusts from the southern Mariana Arc. • Within each map, variation in composition is highly varied and, in some cases, different from whole rock analyses. • Results show that sources of metals to Mn crusts is highly variable in time and space. • Classification diagrams based on whole rock analyses do not reflect the true variation in metal sources to Mn crusts. [ABSTRACT FROM AUTHOR]

The electrophysiological properties of the gap associated with the cavotricuspid isthmus (CTI) block line near the inferior vena cava (IVC) are not fully elucidated. Of 143 patients who underwent CTI block line ablation between September 2020 and April 2021, high-resolution CTI gap mapping was performed for 15 patients. Four patients were identified as having a gap near the IVC (IVC-side gap) despite wide double potentials (DPs) with > 90 ms intervals at the block line. Detailed gap mapping during coronary sinus ostial pacing was performed before and after touch-up ablation. CTI conduction delays caused by an IVC-side gap were classified into 3 patterns: (1) conduction delay at the IVC-side gap without detouring gap conduction, (2) detouring gap conduction due to intrinsic lower lateral right atrium (LLRA)-IVC functional block, and (3) detouring gap conduction due to LLRA-IVC conduction block created by lateral deviation of the CTI ablation line. In Pattern 2, IVC-side gap conduction traveled backward toward the crista terminalis below the LLRA-IVC junction and came back forward again above the border. One patient presented with a head-to-bottom activation pattern of the lateral right atrium (pseudo-CTI block). Pattern 3 was caused by lateral deviation of initial RF deliveries and presented with the same course as intrinsic LLRA-IVC functional block. All patients had wide DP intervals near the tricuspid annulus (mean, 112 ms) and just above the gap site (mean, 109 ms). An IVC-side gap associated with the CTI block line can present with various conduction delay patterns. [ABSTRACT FROM AUTHOR]

Sedimentary systems developed in small (<1 km2) mountain lacustrine basins represent high-resolution geological archives, able to record subtle climatic and tectonic signatures over historical times. The studied example from the Mt. Ragola ophiolitic massif in the Northern Apennines (Italy) allowed us to better understand the role of the different (neo)tectonic and climatic events on the development and distribution of large landslides and lakes/peat bogs during the last 10 kyrs. Implementing a multidisciplinary approach that includes detailed acquisition of bedrock, geomorphological, topographic, and geophysical data, we detected and mapped ridge splitting, trenches, closed depressions, double ridges, and counterscarps. These morphostructures are interpreted as relevant factors influencing the distribution of sediments in historical times by shifting the position of the local equilibrium point (i.e., erosion vs. deposition) and have been correlated to a combination of climatic (i.e., increased flood events) and tectonic (i.e., spatial–temporal clustering of seismic shocks) forcing, starting from the demise of the Little Ice Age in the mid-19th century to the present-day situation. This approach allowed us to better describe the current changes in the hydrologic cycle, reaching beyond the limits of historical instrumental data. Furthermore, allowing the recognition and dating of recent tectonic vs. gravitational deformations, it also constitutes an integrative method for assessing the local geological hazard. [ABSTRACT FROM AUTHOR]

Background: Cutaneous electrogastrography (EGG) is a non-invasive technique that detects gastric bioelectrical slow waves, which in part govern the motility of the stomach. Changes in gastric slow waves have been associated with a number of functional gastric disorders, but to date accurate detection from the body-surface has been limited due to the low signal-to-noise ratio. The main aim of this study was to develop a flexible active-electrode EGG array.Methods: Two Texas Instruments CMOS operational amplifiers: OPA2325 and TLC272BID, were benchtop tested and embedded in a flexible linear array of EGG electrodes, which contained four recording electrodes at 20-mm intervals. The cutaneous EGG arrays were validated in ten weaner pigs using simultaneous body-surface and serosal recordings, using the Cyton biosensing board and ActiveTwo acquisition systems. The serosal recordings were taken using a passive electrode array via surgical access to the stomach. Signals were filtered and compared in terms of frequency, amplitude, and phase-shift based on the classification of propagation direction from the serosal recordings.Results: The data were compared over 709 cycles of slow waves, with both active cutaneous EGG arrays demonstrating comparable performance. There was an agreement between frequencies of the cutaneous EGG and serosal recordings (3.01 ± 0.03 vs 3.03 ± 0.05 cycles per minute; p = 0.75). The cutaneous EGG also demonstrated a reduction in amplitude during abnormal propagation of gastric slow waves (310 ± 50 µV vs 277 ± 9 µV; p < 0.01), while no change in phase-shift was observed (1.28 ± 0.09 s vs 1.40 ± 0.10 s; p = 0.36).Conclusion: A sparse linear cutaneous EGG array was capable of reliably detecting abnormalities of gastric slow waves. For more accurate characterization of gastric slow waves, a two-dimensional body-surface array will be required. [ABSTRACT FROM AUTHOR]

Purpose: The LUMIPOINT™ software module was developed to aid the physician in determining the mechanism of individual atrial tachycardias (ATs). The purpose of this study was to assess the clinical utility of the SKYLINE™ histogram that is a part of LUMIPOINT™.Methods: This study included consecutive patients with iatrogenic sustained AT who underwent catheter ablation using conventional mapping (RHYTHMIA™). SKYLINE™ patterns were analyzed offline and classified into two types: (1) focal type (type-F) exhibiting a low-amplitude (relative activating surface area < 10%) plateau period and (2) reentrant type (type-R) showing no plateau period. How well the two patterns distinguished between focal and macroreentrant ATs as determined by conventional mapping was evaluated.Results: We studied 101 iatrogenic ATs in 91 patients (female: 24, mean age: 67.3 ± 9.1 years). Activation mapping revealed 79 (78.2%) macroreentrant, 6 (5.9%) localized reentrant, and 16 (15.8%) focal ATs. Among the 72 type-R ATs, the mechanism was truly a macroreentry in 70 ATs. However, one focal AT and one localized reentrant AT displayed a type-R pattern (pseudo-reentry pattern). In the 29 type-F ATs, nine macroreentrant ATs were recognized (pseudo-focal pattern). Using SKYLINE™ type-R to differentiate macroreentrant AT from AT with centrifugal activation (focal or localized reentry), the sensitivity and specificity were 88.6% and 90.9%, respectively. Even when the SKYLINE™ type did not match the mapping-based AT mechanism, all discrepancies were electrophysiologically explicable using the SKYLINE™ histograms.Conclusions: SKYLINE™ histograms are a useful tool for the intuitive diagnosis of AT mechanisms. [ABSTRACT FROM AUTHOR]

Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV), which are transmitted by the soil-borne plasmodiophorid Polymyxa graminis , cause high yield losses in barley. In previous studies, the recessive BaMMV resistance gene rym15 , derived from the Japanese landrace Chikurin Ibaraki 1, was mapped on chromosome 6HS of Hordeum vulgare. In this study, 423 F4 segmental recombinant inbred lines (RILs) were developed from crosses of Chikurin Ibaraki 1 with two BaMMV-susceptible cultivars, Igri (139 RILs) and Uschi (284 RILs). A set of 32 competitive allele-specific PCR (KASP) assays, designed using single nucleotide polymorphisms (SNPs) from the barley 50 K Illumina Infinium iSelect SNP chip, genotyping by sequencing (GBS) and whole-genome sequencing (WGS), was used as a backbone for construction of two high-resolution maps. Using this approach, the target locus was narrowed down to 0.161 cM and 0.036 cM in the Igri × Chikurin Ibaraki 1 (I × C) and Chikurin Ibaraki 1 × Uschi (C × U) populations, respectively. Corresponding physical intervals of 11.3 Mbp and 0.281 Mbp were calculated for I × C and C × U, respectively, according to the Morex v3 genome sequence. In the 0.281 Mbp target region, six high confidence (HC) and two low confidence (LC) genes were identified. Genome assemblies of BaMMV-susceptible cultivars Igri and Golden Promise from the barley pan-genome, and a HiFi assembly of Chikurin Ibaraki 1 together with re-sequencing data for the six HC and two LC genes in susceptible parental cultivar Uschi revealed functional SNPs between resistant and susceptible genotypes only in two of the HC genes. These SNPs are the most promising candidates for the development of functional markers and the two genes represent promising candidates for functional analysis. [ABSTRACT FROM AUTHOR]

Ecological footprint (EF) plays an important role in ecological and geographical analysis, but it can only be calculated based on statistical data in a region like a country or a city. High-resolution mapping of ecological footprint is in urgent need for fine-grained analysis of carbon emission and resource consumption. However, current downscaling methods, based on classical statistical models, cannot achieve satisfactory results, because most of them neglect the huge gap of scale between training samples and predicting ones, trying to estimate gridded ecological footprint with only one black-box model. To solve this problem, this paper proposes an innovative AI method for high-resolution mapping of ecological footprint, namely GeoUNet, which can accomplish an end-to-end multi-scale prediction using multi-source datasets. Our experiments indicate that GeoUNet can surpass mainstream downscaling methods in mean square error (MSE) and upscaling mean square error (UMSE). High-resolution gridded EF results obtained by GeoUNet can reveal the spatial heterogeneity of ecological footprint and can be used in fine-scale spatio-temporal analysis.

Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV), which are transmitted by the soil-borne plasmodiophorid Polymyxa graminis, cause high yield losses in barley. In previous studies, the recessive BaMMV resistance gene rym15, derived from the Japanese landrace Chikurin Ibaraki 1, was mapped on chromosome 6HS of Hordeum vulgare. In this study, 423 F4 segmental recombinant inbred lines (RILs) were developed from crosses of Chikurin Ibaraki 1 with two BaMMV-susceptible cultivars, Igri (139 RILs) and Uschi (284 RILs). A set of 32 competitive allele-specific PCR (KASP) assays, designed using single nucleotide polymorphisms (SNPs) from the barley 50 K Illumina Infinium iSelect SNP chip, genotyping by sequencing (GBS) and whole-genome sequencing (WGS), was used as a backbone for construction of two high-resolution maps. Using this approach, the target locus was narrowed down to 0.161 cM and 0.036 cM in the Igri × Chikurin Ibaraki 1 (I × C) and Chikurin Ibaraki 1 × Uschi (C × U) populations, respectively. Corresponding physical intervals of 11.3 Mbp and 0.281 Mbp were calculated for I × C and C × U, respectively, according to the Morex v3 genome sequence. In the 0.281 Mbp target region, six high confidence (HC) and two low confidence (LC) genes were identified. Genome assemblies of BaMMV-susceptible cultivars Igri and Golden Promise from the barley pan-genome, and a HiFi assembly of Chikurin Ibaraki 1 together with re-sequencing data for the six HC and two LC genes in susceptible parental cultivar Uschi revealed functional SNPs between resistant and susceptible genotypes only in two of the HC genes. These SNPs are the most promising candidates for the development of functional markers and the two genes represent promising candidates for functional analysis.

Common fragile sites (CFSs) are specific genomic loci prone to forming gaps or breakages upon replication perturbation, which correlate well with chromosomal rearrangement and copy number variation. CFSs have been actively studied due to their important pathophysiological relevance in different diseases such as cancer and neurological disorders. The genetic locations and sequences of CFSs are crucial to understanding the origin of such unstable sites, which require reliable mapping and characterizing approaches. In this review, we will inspect the evolving techniques for CFSs mapping, especially genome-wide mapping and sequencing of CFSs based on current knowledge of CFSs. We will also revisit the well-established hypotheses on the origin of CFSs fragility, incorporating novel findings from the comprehensive analysis of finely mapped CFSs regarding their locations, sequences, and replication/transcription, etc. This review will present the most up-to-date picture of CFSs and, potentially, a new framework for future research of CFSs. [ABSTRACT FROM AUTHOR]

Abstract Purpose A novel ablation catheter capable of local impedance (LI) monitoring (IntellaNav MiFi OI, Boston Scientific) has been recently introduced to clinical practice. We aimed to determine the optimal LI drops for an effective radiofrequency ablation during cavo‐tricuspid isthmus (CTI) ablation. Methods This retrospective observational study enrolled 50 consecutive patients (68 ± 9 years; 34 males) who underwent a CTI ablation using the IntellaNav MiFi OI catheter, guided by Rhythmia. The LI at the start of radiofrequency applications (initial LI) and minimum LI during radiofrequency applications were evaluated. The absolute and percentage LI drops were defined as the difference between the initial and minimum LIs and 100× absolute LI drop/initial LI, respectively. Results A total of 518 radiofrequency applications were analyzed. The absolute and percentage LI drops were significantly greater at effective ablation sites than ineffective sites (median, 15 ohms vs 8 ohms, P

Common fragile sites (CFSs) are specific genomic loci prone to forming gaps or breakages upon replication perturbation, which correlate well with chromosomal rearrangement and copy number variation. CFSs have been actively studied due to their important pathophysiological relevance in different diseases such as cancer and neurological disorders. The genetic locations and sequences of CFSs are crucial to understanding the origin of such unstable sites, which require reliable mapping and characterizing approaches. In this review, we will inspect the evolving techniques for CFSs mapping, especially genome-wide mapping and sequencing of CFSs based on current knowledge of CFSs. We will also revisit the well-established hypotheses on the origin of CFSs fragility, incorporating novel findings from the comprehensive analysis of finely mapped CFSs regarding their locations, sequences, and replication/transcription, etc. This review will present the most up-to-date picture of CFSs and, potentially, a new framework for future research of CFSs.

Background: Pacing cycle length (PCL)-dependent changes in left atrial (LA) electrophysiologic properties have not been fully elucidated., Objective: We aimed to elucidate these changes using a high-resolution mapping system., Methods: Forty-eight patients underwent atrial fibrillation ablation with RHYTHMIA HDx. Paired LA maps under a baseline PCL (600 ms) and rapid PCL (300 ms) were acquired after pulmonary vein isolation under right atrial appendage pacing. The PCL-dependent change in the low-voltage area (LVA; area with <0.5 mV bipolar voltage), LA activation time (interval from first LA activation to wavefront collision at lateral wall), regional mean voltage, regional mean wave propagation velocity, and slow conduction area (area with <0.3 m/s wave propagation velocity) were quantitatively analyzed., Results: Under the rapid PCL, the total LVA was significantly increased (7.6 ± 9.5 cm 2 vs 6.7 ± 7.6 cm 2 ; P = .031), especially in patients with a 10 cm 2 LVA on the baseline PCL map (21.5 ± 9.1 cm 2 vs 18.1 ± 6.5 cm 2 ; P = .013). The LA activation time was also prolonged (87.9 ± 16.2 ms vs 84.0 ± 14.0 ms; P < .0001). Although the rapid PCL did not decrease the regional mean voltage, it significantly decreased the regional mean wave propagation velocity and increased the slow conduction area in all measured regions., Conclusion: LVA and slow conduction area can be emphasized by rapid PCL LA mapping. There may be poor validity in using these areas as absolute atrial fibrillation substrates without considering the PCL-dependent changes., Competing Interests: Disclosures The authors have no conflicts of interest to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: The classical paradigm of scar-related reentrant ventricular tachycardia (VT) features a circuit with a double loop figure-of-eight (F8) activation pattern.Objective: The purpose of this study was to interrogate VT circuits with F8 activation patterns by entrainment mapping to differentiate an active loop from a passive loop.Methods: Sixty VT circuits with >90% of tachycardia cycle length delineated in high resolution were retrospectively analyzed in 55 patients (nonischemic 49%). A pseudo-F8 VT circuit was defined as a double loop activation pattern driven by a single loop mechanism with a passive loop that yields a long postpacing interval (postpacing interval - tachycardia cycle length ≥ 30 ms).Results: Single loop activation patterns were observed in 33% (n = 20). Of 40 circuits with F8 patterns by activation mapping, 20 were studied with entrainment mapping, where a passive loop was identified by a long postpacing interval in 50%. In 6 circuits where entrainment mapping was performed from both outer loop regions, all demonstrated asymmetric responses to entrainment, confirming a single loop mechanism. Entrainment from both lateral margins of the common pathway (n = 7) demonstrated an asymmetric response in 29%. In all pseudo-F8 circuits (n = 10), the shorter loop functioned as the active loop and ablation targeting the active loop side of the isthmus resulted in VT termination with a single radiofrequency application.Conclusion: In a selected cohort, single loop mechanisms are more prevalent than double loop reentry in reentrant human VT. Half of VT circuits with double loop activation patterns can be demonstrated to be sustained by a single active loop mechanism by entrainment mapping. Ablation targeting the shorter active loop resulted in rapid termination during radiofrequency application. [ABSTRACT FROM AUTHOR]

Objective: Gastric contractions are, in part, coordinated by slow-waves. Functional motility disorders are correlated with abnormal slow-wave patterns. Gastric pacing has been attempted in a limited number of studies to correct gastric dysmotility. Integrated electrode arrays capable of pacing and recording slow-wave responses are required. Methods: New flexible surface-contact pacing electrodes (SPE) that can be placed atraumatically to pace and simultaneously map the slow-wave activity in the surrounding area were developed. SPE were applied in pigs in-vivo for gastric pacing along with concurrent high-resolution slow wave mapping as validation. Histology was conducted to assess for tissue damage around the pacing site. SPE were compared against temporary cardiac pacing electrodes (CPE), and hook-shaped pacing electrodes (HPE), for entrainment rate, entrainment threshold, contact quality, and slow-wave propagation patterns. Results: Pacing with SPE (amplitude: 2 mA, pulse width: 100 ms) consistently achieved pacemaker initiation. Histological analysis illustrated no significant tissue damage. SPE resulted in a higher rate of entrainment (64%) than CPE (37%) and HPE (24%), with lower entrainment threshold (25% of CPE and 16% of HPE). High resolution mapping showed that there was no significant difference between the initiated slow-wave propagation speed for SPE and CPE (6.8 ± 0.1 vs 6.8 ± 0.2 mm/s, P>0.05). However, SPE had higher loss of tissue lead contact quality than CPE (42 ± 16 vs 13 ± 10% over 20 min). Conclusion: Pacing with SPE induced a slow-wave pacemaker site without tissue damage. Significance: SPE offered an atraumatic pacing electrode with a significant reduction of power consumption and placement time compared to impaled electrodes. [ABSTRACT FROM AUTHOR]

Introduction: Local impedance (LI) drops during radiofrequency ablation can predict lesion formation. Some conduction gaps during pulmonary vein isolation (PVI) can be associated with nonendocardial connections. This study aimed to investigate the incidence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during an LI‐guided PVI. Methods and Results: We prospectively enrolled 157 consecutive patients undergoing an initial LI‐guided extensive PVI of atrial fibrillation (AF). After the first‐pass encirclement, the residual conduction gaps and reconnected gaps were mapped using Rhythmia (Boston Scientific) and a mini‐basket catheter. Right and left PV (RPV/LPV) gaps were observed in 22.3% and 18.5% of the patients, respectively: 27 endocardial and 49 nonendocardial gaps. The carina regions were common sites for the gaps (51 carina‐related vs. 25 noncarina‐related). The carina‐related gaps consisted of more nonendocardial gaps than endocardial gaps (RPVs: 90.0% vs. 10.0%, p =.001; LPVs: 76.2% vs. 23.8%, p <.001). A univariate analysis revealed that paroxysmal AF and the left atrial (LA) volume index for RPV endocardial gaps (odds ratio [OR]: 8.640 and 0.946; p =.043 and 0.009), minor right inferior PV diameter for RPV nonendocardial gaps (OR: 1.165; p =.028), and major left inferior PV diameter for LPV endocardial gaps (OR: 1.233; p =.028) were significant predictors. Conclusions: During the LI‐guided PVI, approximately two‐thirds of the conduction gaps were nonendocardial. The carina regions had more conduction gaps than noncarina regions, which was due to the presence of nonendocardial connections. Paroxysmal AF, a lower LA volume index, and larger inferior PV diameters may increase the risk of conduction gaps. [ABSTRACT FROM AUTHOR]

Introduction: Ultrahigh‐density mapping for ventricular tachycardia (VT) is increasingly used. However, manual annotation of local abnormal ventricular activities (LAVAs) is challenging in this setting. Therefore, we assessed the accuracy of the automatic annotation of LAVAs with the Lumipoint algorithm of the Rhythmia system (Boston Scientific). Methods and Results: One hundred consecutive patients undergoing catheter ablation of scar‐related VT were studied. Areas with LAVAs and ablation sites were manually annotated during the procedure and compared with automatically annotated areas using the Lumipoint features for detecting late potentials (LP), fragmented potentials (FP), and double potentials (DP). The accuracy of each automatic annotation feature was assessed by re‐evaluating local potentials within automatically annotated areas. Automatically annotated areas matched with manually annotated areas in 64 cases (64%), identified an area with LAVAs missed during manual annotation in 15 cases (15%), and did not highlight areas identified with manual annotation in 18 cases (18%). Automatic FP annotation accurately detected LAVAs regardless of the cardiac rhythm or scar location; automatic LP annotation accurately detected LAVAs in sinus rhythm, but was affected by the scar location during ventricular pacing; automatic DP annotation was not affected by the mapping rhythm, but its accuracy was suboptimal when the scar was located on the right ventricle or epicardium. Conclusion: The Lumipoint algorithm was as/more accurate than manual annotation in 79% of patients. FP annotation detected LAVAs most accurately regardless of mapping rhythm and scar location. The accuracy of LP and DP annotations varied depending on mapping rhythm or scar location. [ABSTRACT FROM AUTHOR]

Background: Only few studies have been performed that explore the electrophysiological differences between clockwise (CW) and counterclockwise (CCW) right atrial (RA) cavotricuspid isthmus (CTI)‐dependent atrial flutter (AFL) using the high‐resolution Rhythmia mapping system. Objectives: We sought to compare CW and CCW CTI‐dependent AFL in pure right AFL patients (pts) using the ultra‐high‐definition (ultra‐HD) Rhythmia mapping system and we mathematically developed a cartography model based on automatic velocity RA measurements to identify electrophysiological AFL specificities. Methods and Results: Thirty‐three pts were recruited. The mean age was 71 ± 13 years old. The sinus venosus (SV) block line was present in 32/33 of cases (97%) and no significant difference was found between CCW and CW CTI AFL (100% vs. 91%; p =.7). No line was localized in the region of the crista terminalis (CT). A superior gap was present in the posterior line in 14/31 (45.2%) but this was similarly present in CCW AFL, when compared to CW AFL (10/22 [45.5%] vs. 4/10 [40%]; p =.9). When present, the extension of the posterior line of block was observed in 18/31 pts (58%) without significant differences between CCW and CW CI AFL (12/22 [54.5%] vs. 6/10 [60%]; p =.9) The Eustachian ridge line of block was similarly present in both groups (82% [18/22] vs. 45.5% [5/11]; p =.2). The absence of the Eustachian ridge line of block led to significantly slowed velocity in this area (28 ± 10 cm/s; n = 8), and the velocities were similarly altered between both groups (26 ± 10 [4/22] vs. 29.8 ± 11 cm/s [4/11]; p =.6). We created mathematical, three‐dimensional RA reconstruction‐velocity model measurements. In each block localization, when the block line was absent, velocity was significantly slowed (≤20 cm/s). A systematic slowdown in conduction velocity was observed at the entrance and exit of the CTI in 100% of cases. This alteration to the conduction entrance was localized at the lateral side of the CTI for the CCW AFL and at the septal side of the CTI for CW AFL. The exit‐conduction alteration was localized at the CTI septal side for the CCW AFL and at the CTI lateral side for the CW AFL. Conclusion: The ultra‐HD Rhythmia mapping system confirmed the absence of significant electrophysiological differences between CCW and CW AFL. The mechanistic posterior SV and Eustachian ridge block lines were confirmed in each arrhythmia. A systematic slowing down at the entrance and exit of the CTI was demonstrated in both CCW and CW AFL, but in reverse positions. [ABSTRACT FROM AUTHOR]

Parasite infection impacts population dynamics through effects on fitness and fecundity of the individual host. In addition to the known roles of environmental factors, host susceptibility to parasites has a genetic basis that has not been well characterized. We previously mapped quantitative trait loci (QTL) for susceptibility to rat tapeworm (Hymenolepis diminuta) infection in Tribolium castaneum using dominant AFLP markers; however, the resistance genes were not identified. Here, we refined the QTL locations and increased the marker density in the QTL regions using new microsatellite markers, sequence-tagged site markers, and single-strand conformational polymorphism markers. Resistance QTL in three linkage groups (LG3, LG6, and LG8) were each mapped to intervals

New challenges are emerging in fine-scale air quality modeling in China due to a lack of high-resolution emission maps. Currently, only a few emission sources have accurate geographic locations (point sources), while a large part of sources, including industrial plants, are estimated as provincial totals (area sources) and spatially disaggregated onto grid cells based on proxies; this approach is reasonable to some extent but is highly questionable at fine spatial resolutions. Here, we compile a new comprehensive point source database that includes nearly 100,000 industrial facilities in China. We couple it with the frame of Multi-resolution Emission Inventory for China (MEIC), estimate point source emissions, combine point and area sources, and finally map China's anthropogenic emissions of 2013 at the spatial resolution of 30″×30″ (~1 km). Consequently, the percentages of point source emissions in the total emissions increase from less than 30% in the MEIC up to a maximum of 84% for SO 2 in 2013. The new point source-based emission maps show the uncoupled distribution of emissions and populations in space at fine spatial scales, however, such a pattern cannot be reproduced by any spatial proxy used in the conventional emissions mapping. This new accurate high-resolution emission mapping approach reduces the modeled biases of air pollutant concentrations in the densely populated areas compared to the raw MEIC inventory, thus improving the assessment of population exposure. [ABSTRACT FROM AUTHOR]

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Background: High-density automated mapping of complex atrial tachycardias (ATs) requires accurate assessment of activation maps. A new local activation display module (HD coloring, Biosense Webster®) provides higher map resolution, a better delineation of potential block reducing color interpolation, and a new propagation display. We evaluated the accuracy of a dedicated local activation display compared with standard algorithm. Methods: High-density maps from 10 AT were collected with a multipolar catheter and were displayed with standard activation or HD coloring. Six expert operators retrospectively analyzed activation maps and were asked to define (1) the tachycardia mechanism, (2) ablation target, and (3) level of difficulty to interpret those maps. Results: Using HD coloring, operators were able to reach a correct diagnosis in 93% vs. 63%, p < 0.05 compared to standard activation maps. Time to diagnosis was shorter 1.9 ± 1.0 min vs. 3.9 ± 2.1 min, p < 0.05. Confidence level would have allowed ablation without necessity for entrainment maneuvers in 87% vs. 53%, p < 0.05. Operators would have needed to remap or proceed with multiple entrainments in 3% vs. 13% of cases, p < 0.05. Finally, ablation strategy was more accurately identified in 97% vs. 67%, p < 0.05. Conclusion: Activation mapping with the new HD coloring module allowed a more accurate, reliable, and faster interpretation of complex ATs mechanisms compared to standard activation maps. [ABSTRACT FROM AUTHOR]

Background: Late potential (LP) elimination has been proposed as a surrogate endpoint for scar-related ventricular tachycardia (VT) ablation procedures. The characteristics, distribution, and predictors of persistent late potentials (pLPs) after ablation have not been studied., Objective: The purpose of this study was to characterize the spatial distribution and features of pLP after catheter ablation of VT substrate with high-resolution mapping., Methods: Cases of scar-related VT ablation with adequate pre- and postablation electroanatomic maps (EAMs) acquired exclusively using a high-density grid catheter were reviewed from 2021 to 2023., Results: A total of 62 EAMs (pre- and postablation) from 31 cases using a high-density grid catheter were reviewed. pLPs were observed in 19 cases (61%) after ablation. New LP, spatially distinct from preablation LP, at the periphery of the ablation area comprised the majority of pLPs (16/19 [84%]). Isolated pLPs were more prevalent than fractionated pLPs, with a median amplitude of 0.26 mV (0.09-0.59 mV). The presence of pLP was associated with a significantly lower left ventricular ejection fraction (LVEF) and septal ablation but not low voltage, LP, or ablation area compared to absence of pLP (22.8% ± 7.8% vs 31.5% ± 8.0%, P = .008 for LVEF; 83% vs 44%, P = .033 for septal ablation)., Conclusion: Formation of spatially distinct new LP after targeted VT ablation is common, especially in patients with lower LVEF and septal substrate independent of ablation burden. This finding highlights the limitations of complete LP elimination as an endpoint to VT ablation procedures., Competing Interests: Disclosures Shreel Joshi is an employee of Abbott Laboratories, manufacturer of the mapping system and catheters used in this study. All other authors have no conflicts to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Eight-millimeter-tip ablation catheters are characterized by poor mapping resolution as they depend on electrode size and spacing. IntellaTip MiFi XP 8-mm (Boston Scientific) catheters offer high mapping resolution due to 3 mini-electrodes (ME) located at the distal tip of the catheter and are dedicated for cavo-tricuspid isthmus (CTI) radiofrequency ablation (RFA). The aim of the study was to evaluate the usefulness, effectiveness and safety of novel IntellaTip MiFi XP catheter for CTI RFA and its ability to localize anatomical structures of the heart. Methods: The study included 10 patients referred for atrial flutter ablation. The 3D mapping system EnSite Velocity was utilized for catheter visualization. The ME signals were used for tricuspid annulus visualization, RF delivery effectiveness assessment defined as ME signal attenuation, and localization of the gaps in the ablation line. The use of ME signals for TV annulus localization resulted in a 13.9 mm (35.5 ± 4.8 mm vs 49.4 ± 7.8 mm; p < 0.01) shorter ablation line in comparison with the potential ablation line designed using standard bipol. The ablation endpoint, bidirectional block, was achieved in all 10 cases (100%) and lasted for at least 15 min after the last RF delivery. The ablation endpoint was reached after 5.1 ± 1.67 RF applications. The total RF time was 220 ± 61 s. Total procedure time was 66 ± 13.5 min, fluoroscopy time 3.92 ± 4.21 min, and total fluoroscopy dose 40.3 ± 56.5 mGy. Results: In 3 out of 10 cases, there was a need of filling the gap with 1–2 additional applications after the first linear lesion set. No additional RF applications were required at the annular end of the ablation line. The indirect comparison with previously conducted studies using a standard 8-mm ablation catheter shows that the studied catheter has at least the same or even better performance. Conclusions: The use of the novel IntellaTip MiFi XP may help to avoid unnecessary RF application especially at the annular part of cavo-tricuspid isthmus and enables a purely electrophysiological approach to atrial flutter ablation, as high-resolution ME signals help to understand local electrophysiological phenomena. [ABSTRACT FROM AUTHOR]

Cryoballoon ablation is a recognized and widespread method for pulmonary vein isolation. For many years the impossibility of using it to create additional lines was considered a drawback of this approach. However, recently, the technique was adapted to allow the creation of rooflines, and potentially also inferior lines. In this article, we present the first reported case of a patient submitted to pulmonary vein isolation plus posterior wall isolation using the novel Boston POLAR X™ cryoballoon exclusively. To confirm the quality of the lesions, the patient underwent pre and postablation high‐density mapping. [ABSTRACT FROM AUTHOR]