Polar Science最新文献

{"title":"Elucidating the influence of freshwater and sympagic inputs on biogeochemical cycling in the Canadian Arctic Archipelago","authors":"Frances Simone Crable ,&nbsp;Cynthia Garcia ,&nbsp;Alessandra D'Angelo ,&nbsp;Samira Umar ,&nbsp;Brice Loose ,&nbsp;Max Berkelhammer ,&nbsp;Andrew Luke King ,&nbsp;Miquel Gonzalez-Meler","doi":"10.1016/j.polar.2025.101355","DOIUrl":"10.1016/j.polar.2025.101355","url":null,"abstract":"<div><div>The Canadian Arctic Archipelago (CAA) receives significant freshwater inputs from rivers, sea ice, and glacial melt that influence ocean processes and biogeochemical cycles. This study presents a baseline dataset of hydrography and isotopic composition of seawater and suspended particulate organic matter from summer 2019, providing a framework to evaluate long-term biogeochemical changes due to Arctic shifts. Using salinity-δ¹⁸O relationships, temperature, Chl-a fluorescence, and macronutrients, interactions between ocean, cryosphere, and terrestrial inputs were characterized. δ¹⁸O indicated glacial and sea ice melt contributions associated with salinity-influenced stratification and depleted surface nutrients. Notably, surface nitrate + nitrite in the freshest waters (0.06–1.2 μM at S = 25–29) showed no enrichment compared to saline waters (S &gt; 30), with no correlation between nutrients and salinity. Depleted δ¹⁵N_PON (particulate organic nitrogen) and δ¹³C_POC (particulate organic carbon) were observed across the region. Low temperatures, pCO_2, and sea ice likely contributed to low δ¹³C_POC, although overlapping drivers of PON and POC isotopic signatures remain unclear. δ¹³C_POC values became enriched with increasing POC concentration (r² = 0.45 surface, r² = 0.61 at Chl-a maximum), with the most depleted values (−34 ‰) at the lowest POC. Enriched δ¹³C_POC and δ¹⁵N_PON correlated with elevated carbon (C) biomass in channels with sea ice, possibly linked to sympagic algal inputs. Nitrogen limitation occurred across transects, with N:P (NO₃:PO₄) ratios consistently below Redfield (16:1), unalleviated by freshwater inputs. These observations serve as a reference for future studies on freshwater impacts on Arctic productivity, with July–August sampling reflecting post-bloom conditions where freshwater primarily acts as a barrier to mixing, not a nutrient source.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"47 ","pages":"Article 101355"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147426649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sympagic communities of the seasonal drift ice fields in the Kara and northeastern Barents Seas","authors":"Anna I. Timchenko ,&nbsp;Daria A. Portnova ,&nbsp;Olga A. Sashova ,&nbsp;Iaroslava P. Protsiuk ,&nbsp;Egor A. Blagodatskikh","doi":"10.1016/j.polar.2025.101310","DOIUrl":"10.1016/j.polar.2025.101310","url":null,"abstract":"<div><div>Changes in the retreating ice edge and decaying ice dynamics in seasonally ice-covered marginal seas can significantly impact the functioning of sympagic communities. This study characterized the diversity and abundance of poorly studied sympagic flora and fauna, as well as their ice drift paths, in the Kara and northeastern Barents Seas during the summer melt seasons of 2021 and 2023. We collected seasonal drifting ice floes, 3–40 cm thick, from a ship's side close to the ice edge and within broken ice fields of varying consolidation. We observed that the overall low values of chlorophyll <em>a</em> (Chl <em>a</em>) concentrations (0.04–0.32 mg/m³), microalgal abundance (10–176.3 × 10³ cells/L), biomass (12.20–120.60 μgC/L), and faunal abundance (0–23 ind/L) could indicate significant patchiness, a decline in productivity, and the release of organisms during the breakup and melting of ice. The taxonomic composition of microalgae in the ice floes consisted of 28 taxa and was dominated by pennate diatoms (Pennales sp., <em>Fragilariopsis oceanica</em>, <em>Cylindrotheca closterium</em>, <em>Nitzschia</em> spp.) and dinoflagellates (<em>Peridiniella catenata</em>, <em>Protoperidinium pellucidum</em>). The metazoan fauna comprised 13 taxa. Rotifers and nematodes (<em>Theristus melnikovi</em> and <em>Cryonema tenue</em>) were the predominant groups, with occasional occurrences of copepods, amphipods, and a single ostracod, bivalve, and halacarid mite specimens. Analysis of sea ice drift trajectories suggests that the sea ice on the inner Kara Sea shelf formed in shallow water and was transported northward to regions with deeper water and distinct hydrological regimes. This transport likely affected the composition of the ice-associated communities.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"47 ","pages":"Article 101310"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147427687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The third-quarter time phenomenon: State of research, findings, and perspectives in isolated, confined, and extreme environments","authors":"Karine Paret ,&nbsp;Katia Collomp ,&nbsp;Aude Villemain","doi":"10.1016/j.polar.2025.101354","DOIUrl":"10.1016/j.polar.2025.101354","url":null,"abstract":"<div><div>The Third-Quarter Time (TQT) phenomenon is a psychological and physical state observed in isolated, confined, and extreme (ICE) environments, emerging during the third quarter of long-duration missions. Characterized by mood swings, anxiety, and interpersonal tensions, TQT remains underexplored despite consistent reports from polar research and space missions. To address this, the PAHPA ICE program, supported by ESA and IPEV, is conducting multidisciplinary research at Concordia Station using a Mixed Methods framework. By combining physiological, psychological, and qualitative data, PAHPA ICE aims to identify the factors contributing to TQT and improve adaptation strategies for extreme environments. Insights gained from Concordia are expected to enhance well-being and resilience, not only for polar missions but also for space exploration and submarine deployments.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"47 ","pages":"Article 101354"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147426651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimating the probability of human error for navigational safety in the Arctic waters","authors":"Mehmet Kaptan","doi":"10.1016/j.polar.2025.101313","DOIUrl":"10.1016/j.polar.2025.101313","url":null,"abstract":"<div><div>The increase in maritime traffic in Arctic waters is a consequence of global warming, reducing the distance vessels must navigate compared to traditional routes. However, unlike conventional maritime routes, Arctic waters pose substantial risks to vessel navigation, including ice conditions, dense fog, strong winds, rapidly changing weather conditions, and inadequate navigation and communication aids. It is vital to assess potential man-made hazards to prevent these risks from escalating into accidents that may result in material and human casualties. In this context, human error probabilities in operational tasks on board for navigation safety in Arctic waters were calculated by integrating the Delphi-Analytic Hierarchy Process (AHP) technique into the Human Error Assessment and Reduction Technique (HEART), one of the human reliability analysis (HRA) methods. As a result of the study, the average human error probability (HEP) value for all operations on board, related to navigation safety in Arctic waters, was found to be 4.93E-01. Tasks that demand experience and training were observed to have a higher likelihood of error.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"47 ","pages":"Article 101313"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147426642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Security risks to commercial ships in the Arctic Ocean due to high tension among states","authors":"Hristos Karahalios","doi":"10.1016/j.polar.2026.101356","DOIUrl":"10.1016/j.polar.2026.101356","url":null,"abstract":"<div><div>Navigation of ships in the Arctic Ocean is beneficial for world trade. However, ship security threats may appear due to maritime disputes. This paper aims to identify navigation security risks at different escalation levels among arctic states. In this paper, a conflict escalation game theory for three Arctic states is carried out. At each escalation scenario, an aggressor state has the option to practice certain tactics. Tactics were selected by examining similar maritime dispute conflicts, such as military exercises, rescue operations, and broadcasting safety messages to claim territorial rights in dispute sea zones. Then, escalation scenarios are examined, showing the navigation threats for commercial ships. Results show that a middle-level escalation by an aggressive state could be beneficial to achieving its territorial claims. On the other hand, several navigation risks could cause maritime casualties in a sensitive area. Several studies have covered the issue of safety navigation in the Arctic Ocean and the need for cooperation among states. The originality of this paper lies in examining how each escalation phase could cause risk to commercial ships, urging the need to establish safe navigation zones in the area.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"47 ","pages":"Article 101356"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147426643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A geological cross section of Neogene to Quaternary sediments in the Larsemann Hills, East Antarctica","authors":"Nikita Demidov ,&nbsp;Sergey Verkulich ,&nbsp;Zinaida Pushina ,&nbsp;Elizaveta Rivkina ,&nbsp;Denis Shmelev ,&nbsp;Oksana Zanina ,&nbsp;Natalya Belova ,&nbsp;Martin Melles ,&nbsp;Janet Rethemeyer","doi":"10.1016/j.polar.2025.101214","DOIUrl":"10.1016/j.polar.2025.101214","url":null,"abstract":"<div><div><span>Drilling of 5 holes between the lakes Reid and Nella in the Larsemann Hills oasis of East Antarctica revealed up to 15 m thick Neogene - Quaternary deposits above bedrock. Laboratory analyses comprise cryolithological, geochemical, and micropaleontological investigations, as well as radiocarbon (</span>¹⁴<span>C) dating. The lowermost sediments according to key biostratigraphical taxa are of early Pliocene age and were deposited in shallow marine conditions. This unit is overlain by sediments, which according to </span>¹⁴<span>C dating were deposited ca. 48.1–29.6 ka BP. Their formation in lacustrine-marine conditions, as reflected by results of multi-proxy laboratory studies, suggests that the relative sea level during Marine Isotope Stage<span><span><span> 3 has been at least 32 m higher than present, in order to allow lagoon-type deposition, when fresh lake water mixed with sea water during high tides, or near coastal marine sedimentation, when sea water mixed with melt water from adjacent </span>glaciers. The sediments at the top of the record are tills, consisting of a lateral moraine and an </span>end moraine<span>. Their distribution marks the extend of the last glaciation<span> in the area, with ice masses moving northward during the pre-Antarctic Cold Reversal glaciation 14 ka BP, or during a minor Holocene ice advance.</span></span></span></span></div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"46 ","pages":"Article 101214"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145739078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Initial transformation and export of dense shelf water from the Prydz Bay and Cape Darnley regions: A Lagrangian perspective using clustered drifters","authors":"Margaret Murakami ,&nbsp;Aleksi Nummelin ,&nbsp;Benjamin Keith Galton-Fenzi ,&nbsp;Petteri Uotila","doi":"10.1016/j.polar.2025.101261","DOIUrl":"10.1016/j.polar.2025.101261","url":null,"abstract":"<div><div>Antarctic Bottom Water (AABW) forms the deepest limb of the meridional overturning circulation (MOC) and is a key control in global heat, freshwater, and carbon exchanges. AABW originates in part from Dense Shelf Water (DSW) produced in Antarctic coastal polynyas. Prydz Bay and Cape Darnley host several productive polynyas that supply AABW to the Atlantic and Indian Ocean sectors. However, the pathways by which DSW travels from the shelf to the abyss, and the transformations it undergoes over its first year, remain poorly understood. We use a 10 km circum-Antarctic ocean-sea ice model (the Whole Antarctic Ocean Model) and Lagrangian particle tracking with a novel clustering analysis to examine how DSW from Prydz Bay region is exported and modified before contributing to AABW. Our results reveal that shelf mixing influences DSW’s fate. When DSW flows beneath the Amery Ice Shelf, it mixes with fresher Ice Shelf Water (ISW), becoming less dense and reducing its potential to sink. Along the shelf break, intrusions of Circumpolar Deep Water (CDW) mix with DSW to form modified CDW (mCDW), further altering its properties. We find that the DSW-to-AABW pathway is sensitive to these mixing processes, which can either facilitate or preclude descent. Cluster analysis of Lagrangian trajectories reveals distinct groups of particle pathways and transformations, highlighting the diverse outcomes of DSW export. This Lagrangian approach demonstrates a powerful tool for diagnosing shelf-to-deep water mass transformation, and provides insights into the processes regulating AABW formation in the Prydz Bay region.</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"46 ","pages":"Article 101261"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145739056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin of retrograde saline fluids during collision zone high-temperature metamorphism constrained from whole-rock sulfur isotope composition, the Sør Rondane Mountains, East Antarctica","authors":"Tetsuo Kawakami ,&nbsp;M. Satish-Kumar ,&nbsp;Tokuya Mitsubori ,&nbsp;Silpa Ammini Sasidharan ,&nbsp;Hayato Ikeda ,&nbsp;Fumiko Higashino ,&nbsp;Tatsuro Adachi ,&nbsp;Masaoki Uno","doi":"10.1016/j.polar.2025.101213","DOIUrl":"10.1016/j.polar.2025.101213","url":null,"abstract":"<div><div><span><span>Origin of saline fluids infiltrated during the retrograde metamorphism in the Sør Rondane Mountains (SRM), East </span>Antarctica<span><span> is constrained using whole-rock sulfur isotopic compositions<span>. The SRM exposes granulite facies </span></span>lower crust<span> of ca. 650-500 Ma continental collision zone from which syn-metamorphic Cl-rich fluid infiltrations have been reported. In this study, we determined whole-rock sulfur isotopic compositions of felsic and mafic gneisses with or without the evidence for saline fluid infiltrations. The felsic gneisses gave a wide range of δ</span></span></span>³⁴S from −7.0 to +12.0 ‰ that overlap with δ³⁴<span>S of modern sedimentary sulfides and sulfides in granitoids. The mafic gneisses mostly gave δ</span>³⁴S from −6.0 to +3.9 ‰, consistent with δ³⁴<span>S of sulfides in basalts and gabbros. A mafic wall rock of the Cl-rich hornblende-garnet selvage formed by retrograde saline fluid infiltration gave δ</span>³⁴S of +12.8 ‰, which is higher than δ³⁴S of sulfides in basalts and gabbros, suggesting that the saline fluid added high δ³⁴S to the mafic wall rock. Since the Cl-rich selvages are connected to granitic veins, the source of saline fluid is considered as granitoids that intruded during the retrograde metamorphism. Felsic gneisses with high δ³⁴<span>S have microstructural evidence of retrograde S-bearing fluid infiltration, such as garnet<span> rim replaced by sulfide-bearing assemblage. Therefore, both mafic and felsic gneisses in the SRM are shown to have been affected by the saline-fluid infiltrations to rehydrate the collision zone lower crust. The hydration of the SRM by the saline fluids is likely caused by the post-kinematic granitoid intrusions postdating ca. 560 Ma.</span></span></div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"46 ","pages":"Article 101213"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145739091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric pressure waves and seismic signatures of the Hunga Tonga-Hunga Haʻapai eruption in Antarctica","authors":"Vivek Kumar ,&nbsp;Rahul Kumar ,&nbsp;B. Padma Rao ,&nbsp;Anand K. Singh ,&nbsp;Shailendra Saini ,&nbsp;Vijay K. Soni","doi":"10.1016/j.polar.2025.101233","DOIUrl":"10.1016/j.polar.2025.101233","url":null,"abstract":"<div><div><span>The eruption of the Hunga Tonga-Hunga Ha'apai volcano on January 15, 2022, marked a significant geological occurrences, deemed to be rare and powerful explosive event was observed globally. This research paper presents the detection of atmospheric pressure waves and seismic waves at Indian research bases in </span>Antarctica<span>, representing the first documented evidence of the detection of these volcanic seismic and air waves from Antarctica. Despite the considerable distance of 8560 km from the volcano eruption site to Bharati, and 9839 km to Maitri, seismic observations unveiled heightened volcanic activity during the eruption period, signaling increased detection of tectonic and magmatic activity in the region. The Broadband Seismological Observatory (code is BRTI) effectively detected and recorded seismic waves from the eruption, which released energy comparable to that of an earthquake with a surface wave magnitude (Ms) of ∼5.8. The waves took 11.91 min to reach BRTI, aligning precisely with the signal at ∼04:26:49 UTC. Analysis indicates the multiple eruptions of the HT-HH volcanic activity. Further, the findings of Atmospheric data underscore the significance of comprehensive monitoring and research to gain a comprehensive understanding of the intricate interactions between volcanic activity, atmospheric conditions, and the environment. Atmospheric waves, traveling at velocities of 313.5 m/s and 305.9 m/s, reached Bharati and Maitri in Antarctica, respectively.</span></div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"46 ","pages":"Article 101233"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145739076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of the Archean crust in the Indian Ocean coastal sector (Napier Complex, and nearby areas) of Antarctica – Review","authors":"Tomokazu Hokada ,&nbsp;Simon L. Harley","doi":"10.1016/j.polar.2025.101266","DOIUrl":"10.1016/j.polar.2025.101266","url":null,"abstract":"<div><div>The Antarctic continent preserves a long crustal history from Eoarchean through Proterozoic to Phanerozoic. This article summarizes the evolution of Archean crustal fragments in the Indian Ocean coastal sector of Antarctica (Dronning Maud Land, Enderby Land, Kemp Land and MacRobertson Land). The Napier Complex in Enderby Land and western Kemp Land is an Archean craton measureing 400 km by 200 km. It is characterized by old fragments &gt;3850 Ma and high-T to ultrahigh-T regional metamorphism at about 2550–2480 Ma, thus recording a crustal history spanning nearly the entire Archean. The available data, which are sparse relative to the large area covered, suggest that several crustal components of different ages have come together to form the terrane. Numerous studies have focused on the UHT metamorphism of this terrane, with &gt;1000–1100 °C peak metamorphic temperatures and subsequent isobaric cooling evident along with some local variations in the P–T evolutions. In addition to the Napier Complex, the surrounding Proterozoic metamorphic terranes, such as in the Lützow-Holm Complex, the Western Rayner Complex, the Rayner Complex, and the Rauer Islands, include several relatively small Archean crustal blocks. Some areas of the Rayner Complex are thought to be reworked parts of the Napier Complex (Oygarden Islands and the Edward VIII Gulf area). UHT metamorphism of Neoproterozoic to Cambrian age has also been demonstrated in these complex, polymetamorphic areas containing Archean protoliths (Rundvågshetta, Forefinger Point, Mather Supracrustals).</div></div>","PeriodicalId":20316,"journal":{"name":"Polar Science","volume":"46 ","pages":"Article 101266"},"PeriodicalIF":2.0,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145739145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}