Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed greatly.It witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred ...Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed greatly.It witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred frequently at a large scale in a very short time,which has thus attracted much attention among geoscientists at home and abroad.展开更多
OBJECTIVE:To explore the characteristics of blood glucose excursions of type 2 diabetes mellitus patients with three different Traditional Chinese Medicine(TCM) syndromes.METHODS:One hundred and nine patients with typ...OBJECTIVE:To explore the characteristics of blood glucose excursions of type 2 diabetes mellitus patients with three different Traditional Chinese Medicine(TCM) syndromes.METHODS:One hundred and nine patients with type 2 diabetes mellitus were recruited from the Department of Endocrinology and the Department of TCM of the Sixth People's Hospital affiliated to Shanghai Jiao Tong University.Subjects were divided into three groups according to TCM syndrome:intrinsic Damp(n- 42),Yin deficiency and internal Heat(n = 25),and Qi and Yin deficiency(n- 42).Subcutaneous interstitial glucose was monitored with a continuous glucose monitoring system for 3consecutive days to investigate the glycemic profile in each group.Plasma C-peptide levels were measured,and an arginine test was taken in 10 patients randomly selected from each group.Glucose data and glycemic variability were analyzed to investigate the differences among the groups.The change in C-peptide levels and the results from arginine trial were used to evaluate β cell function.RESULTS:Indicators reflecting blood glucose level were the highest in subjects with Yin deficiency and internal Heat syndrome,and parameters reflecting glycemic variability were the lowest in those with Qi and Yin deficiency syndrome.The change in C-peptide levels showed that subjects with Qi and Yin deficiency syndrome had the best βcell function among the three groups;this was confirmed by the arginine trial.CONCLUSION:Patients with Qi and Yin deficiency syndrome had a more stable blood glucose profile,as glycemic variability was higher in those with intrinsic Damp syndrome and those with Yin deficiency and internal Heat syndrome.展开更多
Objective:To probe glycemic excursions in type 2 diabetic patients whose hemoglobin A1c(HbA1c) was kept ≤6.0%.Methods:Totally 36 cases with type 2 diabetes(T2DM) with HbA1c≤6.0% and 30 cases with normal glucose tole...Objective:To probe glycemic excursions in type 2 diabetic patients whose hemoglobin A1c(HbA1c) was kept ≤6.0%.Methods:Totally 36 cases with type 2 diabetes(T2DM) with HbA1c≤6.0% and 30 cases with normal glucose tolerance(NGT) from December 2005 to December 2007 in our department were subjected prospectively.Continuous glucose monitoring system(CGMS) was employed to record their continuous blood glucose level for 3 d.The blood glucose profiles including the mean blood glucose(MBG),standard differentiation(SD),mean amplitude of glycemic excursions(MAGE) and absolute means of daily differences(MODD) were analyzed.Results:T2DM group had obviously postprandial hyperglycemia,in about 2 h after meal,especially after breakfast.Fifty-two hypoglycemic episodes occurred during the monitoring period in T2DM groups,of which 73.1%(38 episodes) were absence of symptomatic hypoglycemia with the lowest value of blood glucose only 2.0 mmol/L.And 20 episodes took place during the day hours,while 32 episodes observed during the night hours.Compared with NGT groups,SD,MAGE and MODD were all significantly higher in T2DM groups.MBG was significantly correlated with HbA1c in T2DM groups,but SD,MAGE,NGE and MODD were all independent of HbA1c.MAGE was independent of MODD.Conclusion:The amplitude of glycemic excursions is higher in normol-controlled T2DM groups than the NGT groups.Thus ideally glycemic control is not only to make HbA1c reach standard,but also to lessen glycemic excursions and reduce hypoglycemia episodes.展开更多
Vertical excursions allow divers in seafloor habitats to work at depths deeper than thehabitat.Descending excursions from saturation in nitrox have almost all used air as the breathing gas;depth is effectively restric...Vertical excursions allow divers in seafloor habitats to work at depths deeper than thehabitat.Descending excursions from saturation in nitrox have almost all used air as the breathing gas;depth is effectively restricted to less than 60 msw by narcosis and oxygenexposure.The objective is to investigate use of helium mixtures for excursions, taking展开更多
Cambrian carbonates with abundant fossils of agnostoid trilobites deposited on the southern slope （Jiangnan slope belt） of the Yangtze Platform and in the Jiangnan deepwater basin are well exposed in the Wangeun Sec...Cambrian carbonates with abundant fossils of agnostoid trilobites deposited on the southern slope （Jiangnan slope belt） of the Yangtze Platform and in the Jiangnan deepwater basin are well exposed in the Wangeun Section of western Hunan, South China, and in the Duibian A Section of western Zhejiang, southeastern China, respectively. To better understand the response of carbonisotope excursions to depositional environment changes, mass extinctions and eustatic events, we collected 530 carbonate samples in fresh roadcut exposures of the two measured sections for analysis of carbon and oxygen isotopic compositions. Data of δ^13C from the Wangcun Section, western Hunan, South China, demonstrate that the Cambrian carbon-isotope profile includes three remarkable positive excursions CPEwc-1, 2, 3 in the Upper Series 2, in the Lower and in the Middle Furongian Series. Three distinctive negative excursions CNEwc,-1, 2, 3 were separately tested in the Lower Terreneuvian Series, Lower Series 3 and in the Upper Furongian Series. Similarly, in the corresponding horizons in the Duibian A Section, Zhejiang Province, southeastern China, three positive excursions CPEdb-1, 2, 3 and three negative excursions CNEdb-1, 2, 3 also have been discovered. We interpret these significant carbon-isotope excursions as being associated with enhanced biogenic prodnctivity, mass extinctions and eustatic events.展开更多
Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that ...Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern China. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.展开更多
The Mauna Loa volcano of the Big Island of Hawaii offers the “ad-hoc” lava flows that have recorded the geomagnetic short-term behavior (i.e. excursions) at two key localities such as the younger Kahuku volcanic ser...The Mauna Loa volcano of the Big Island of Hawaii offers the “ad-hoc” lava flows that have recorded the geomagnetic short-term behavior (i.e. excursions) at two key localities such as the younger Kahuku volcanic series (ca. ~41 ka) where 29 flows are exposed for detailed paleomagnetic sampling making up 102 meters of section where the uppermost flow sampled lies directly under the Pahala ash. The second sampling site is the Ninole volcanic series where 25 flows spanning 56 meters of section were also sampled from the northeast and southwest sides of the Kilohana Ridge. The most recent age estimate indicates that the Kahuku flows can correlate well with the transitional/excursional directional results obtained from both volcanic and deep-sea sediments of the global record of the Laschamp (ca. ~41 ka calendar years B.P) excursion and the Ninole flows which are associated to the also global Pringle Fall excursion (ca. 211 ± 13 ka) recorded at the type section.展开更多
Atmospheric CO_(2)is a key factor governing Earth's habitability,with its concentration and isotopic variations influenced by both deep and shallow carbon cycles.The Neoproterozoic Era was pivotal for Earth's ...Atmospheric CO_(2)is a key factor governing Earth's habitability,with its concentration and isotopic variations influenced by both deep and shallow carbon cycles.The Neoproterozoic Era was pivotal for Earth's habitability evolution and global tectonic reorganization,encompassing the assembly-to-breakup of Rodinia and the formation of Gondwana.During this period,marine carbonateδ^(13)C_(PDB)exhibited repeated positive and negative excursions,with the most pronounced negative shift occurring in the Ediacaran(termed the Shuram Excursion,SE).While conventional models attribute SE to organic matter oxidation(due to its13C-depleted signature),this mechanism faces challenges in explaining associated geological features.Notably,the SE event temporally coincides with peak rifting activity and large-scale carbonatite-alkaline magmatism,suggesting a potential deep carbon cycle contribution.Spatial-temporal-compositional correlations imply that tectonic and magmatic processes may play critical roles in carbonateδ^(13)C excursions,necessitating an Earth system approach integrating deep-shallow carbon cycle.Recent studies propose that Neoproterozoicδ^(13)C excursions could originate from deep carbon recycling,with models highlighting subduction-driven decarbonation and melt recycling during supercontinent cycles.These frameworks offer novel insights into the SE enigma.展开更多
The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a...The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a large negative excursion, comparable to ＂BACE＂ （BAsal Cambrian Carbon isotope Excursion） event, which occurs near the Precambrian-Cambrian boundary with a magnitude of 4‰-10‰ （PDB）; （2） the ＂ZHUCE＂ （ZHUjiaqing Carbon isotope Excursion） event, a distinct positive excursion （over 5%0） that can be recognized at the Fortunian Stage to Stage 2 transition; （3） another strong negative one, so-called ＂ROECE＂ （Redlichiid-Olenellid Extinction Carbon isotope Excursion） event, shifting at the interval between Series 2 and Series 3, peaking at -3‰--5‰ （PDB）; （4） the famous Steptoean positive carbon isotope excursion （SPICE）, which has been widely identified at the base of Furongian Series, Paibian Stage, with an amplitude about 4‰ （PDB）. The four sharp σ13C shifts correlate well with coeval paleoceanographic changes and bioevents. Besides, there are some σ13C excursions from a few sections in previous studies, and more data are required to identify whether they are global or regional ones.展开更多
Background The accurate and comprehensive assessment of glycemic control in patients with diabetes is important for optimizing glycemic management and for formulating personalized diabetic treatment schemes. This stud...Background The accurate and comprehensive assessment of glycemic control in patients with diabetes is important for optimizing glycemic management and for formulating personalized diabetic treatment schemes. This study aimed to analyze the correlation between 1,5-anhydroglucitol （1,5-AG） and glycemic excursions in type 2 diabetic patients. Methods Seventy-one outpatients with type 2 diabetes mellitus were randomly recruited from Chinese People＇s Liberation Army General Hospital. Using a continuous glucose monitoring system （CGMS）, these patients＇ blood glucose levels were monitored for three consecutive days to obtain mean blood glucose （MBG） data. Intraday glycemic excursions were evaluated using the mean amplitude of glycemic excursions （MAGE）, the largest amplitude of glycemic excursions （LAGE）, standard deviation of blood glucose （SDBG） and the M-value. Interday glycemic excursion was assessed by absolute mean of daily difference （MODD）. Postprandial glycemic fluctuations were evaluated using postprandial glucose excursions （PPGE） and postprandial incremental area under the curve （iAUC）. Fasting venous blood samples were collected to measure serum 1,5-AG, whole-blood hemoglobin Alc （HbAlc） and serum glycated albumin （GA）. Clinical markers of glycemia and parameters of glycemic excursions from CGMS were analyzed using the Pearson correlation coefficient and multivariate stepwise regression. Results Pearson correlation analysis revealed that 1,5-AG was significantly correlated with MAGE, SDBG, M-value, LAGE, PPGE and iAUC （r values were-0.509,-0.430,-0.530,-0.462,-0.416 and-0.435, respectively, P 〈0.01）, especially in moderately and well-controlled patients, based on defined HbAlc levels. Multivariate stepwise regression analysis revealed a negative correlation between 1,5-AG and the above parameters, but not HbAlc and GA. Finally, HbAlc and GA were positively correlated with MBG and fasting blood glucose （FBG）. Conclusions 1,5-AG was much better than HbAlc and GA as a marker of glycemic excursions in type 2 diabetic patients. Based on these results 1,5-AG is the best metric for assessing postprandial glucose levels in moderately and well-controlled patients, while HbAlc and GA were superior to 1,5-AG for monitoring MBG and FBG.展开更多
The late Ediacaran Shuram Excursion(SE)records the most prominent negativeδ^(13)C excursions(δ^(13)C=-12‰)during Earth’s history.It has been hypothesized to have resulted from oxidation of dissolved organic matter...The late Ediacaran Shuram Excursion(SE)records the most prominent negativeδ^(13)C excursions(δ^(13)C=-12‰)during Earth’s history.It has been hypothesized to have resulted from oxidation of dissolved organic matter,diagenetic or authigenic precipitates.However,the origin of the SE remains enigmatic;current models face challenges regarding the significant amount of atmospheric oxygen needed to balance such extensive oxidation and sustained inputs of light carbon with extremely negative C isotope compositions.Here,we show that the Doushantuo Formation at the Jiulongwan section in South China,a key stratum recording the SE event,contains mineralogical and geochemical signatures related to igneous processes.Both the occurrence of ankerite,feldspar,moissanite and euhedral quartz in the SE samples and the relatively consistent Ce anomalies of carbonate and O isotopes of quartz indicate a contribution from an igneous source.In particular,the SE samples have trace element and C isotope compositions similar to those of recycled carbonatites formed by decarbonation and melting of sedimentary carbonate rocks.These observations suggest that the deep cycle of ancient carbonate rocks,which were subjected to decarbonation during subduction,melting and eruption related to the breakup of the Rodinia supercontinent,contributed to the SE.This igneous model for the SE may provide a connection between the deep and shallow carbon cycles of the Earth.展开更多
In this paper, the authors investigate the joint distribution of end points of excursion awayfrom a closed set straddling on a fixed time and use this result to compute the Levy systemand the Dirichlet form of the bou...In this paper, the authors investigate the joint distribution of end points of excursion awayfrom a closed set straddling on a fixed time and use this result to compute the Levy systemand the Dirichlet form of the boundary process.展开更多
High-resolution δ13C records are presented for the Miocene benthic foraminifers Cibici doides wuellerstorfi and C. kullenbergi (24-5 Ma) and the planktonic foraminifer Globigerinoides sacculifer (18-5 Ma) from ODP Si...High-resolution δ13C records are presented for the Miocene benthic foraminifers Cibici doides wuellerstorfi and C. kullenbergi (24-5 Ma) and the planktonic foraminifer Globigerinoides sacculifer (18-5 Ma) from ODP Site 1148A (18° 50.17′N, 116° 33.93′E, water depth 3308.3 m),northern South China Sea. The general pattern of parallel benthic and planktonic δ13C shows a decrease trend of δ13C values from the early-middle Miocene to the middle-late Miocene. Two dis tinct δ13C positive excursions at 23.1-22.2 and 17.3-13.6 Ma, and two negative excursions at 10.2-9.4 and 6.9-6.2 Ma have been recognized. All these events are cosmopolitan, providing the good data for the stratigraphic correlation of the South China Sea with the global oceans as well as for studying the changes of the global carbon reservoir and its corresponding climate.展开更多
Two positive d 13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbon-ate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attrib...Two positive d 13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbon-ate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attrib-uted to enhanced organic carbon burial during the F-F biological mass extinction. However, this worldwide pattern has not been revealed from the well-deposited Late Devonian sequences in southern China. In this paper, a detailed inves-tigation has been made on the Late Devonian section at Dongcun, Guilin, southern China to constrain perturbations in d 13C of carbonates in the F-F deposited sequence. The result from this section also indicates two positive d 13C ex-cursions during the F-F transition. The first excursion with an amplitude of 1.5 occurred at the bottom of linguiformis Zone, later than the early excursion existing in the Late rhe-nana Zone of the Late Devonian profiles in other continents, especially, in central Europe. This difference has been ex-pected to be a result as conodont Palmatolepis linguiformis occurred earlier in southern China than other sites. The second excursion with an amplitude of 2.1 is located at the F-F boundary, same as the records from other continents. This result strongly supports the view that two carbon iso-tope positive excursions during the F-F transition are com-mon in carbonate sediments, resulting from worldwide in-creases of organic carbon burial intensity.展开更多
Objective:To evaluate incidence of interscalar excursions between round window (RW) and cochleostomy approaches for cochlear implant (CI) insertion. Methods:This was a retrospective case-comparison. Flat-panel CT (FPC...Objective:To evaluate incidence of interscalar excursions between round window (RW) and cochleostomy approaches for cochlear implant (CI) insertion. Methods:This was a retrospective case-comparison. Flat-panel CT (FPCT) scans for 8 CI users with Med-El standard length electrode arrays were collected. Surgical technique was identified by a combination of operative notes and FPCT imaging. Four cochleae underwent round win-dow insertion and 4 cochleae underwent cochleostomy approaches anterior and inferior to the round window. Results:In our pilot study, cochleostomy approaches were associated with a higher likeli-hood of interscalar excursion. Within the cochleostomy group, we found 29% of electrode contacts (14 of 48 electrodes) to be outside the scala tympani. On the other hand, 8.5%of the electrode contacts (4 of 47 electrodes) in the round window insertion group were extra-scalar to the scala tympani. These displacements occurred at a mean angle of occur-rence of 364°±133°, near the apex of the cochlea. Round window electrode displacements tend to localize at angle of occurrences of 400? or greater. Cochleostomy electrodes occurred at an angle of occurrence of 19°e490°.展开更多
Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventiona...Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventional M-mode(MM)offers high-resolution imaging but requires precise alignment,which can be diffi cult in ICU patients.[3-5]Anatomical M-mode(AMM)allows flexible line adjustment,enabling accurate DE measurements despite poor acoustic windows.[6]However,comparative data between MM and AMM are limited.This retrospective study evaluated the concordance between MM and AMM for assessing right DE.展开更多
Over the past few years, OSL and TCN datings of glacial material from High Asia have come into fashion. To this day, however, these techniques do not permit safe calibration. The intensity of the cosmic ray flux is be...Over the past few years, OSL and TCN datings of glacial material from High Asia have come into fashion. To this day, however, these techniques do not permit safe calibration. The intensity of the cosmic ray flux is being modulated by the solar and terrestrial magnetic fields and their secular fluctuations in the past. So far, these variations cannot be converted into the respective local TCN production rates for High Asia. We have reason to believe that the ages that are being calculated despite these uneertainties are generally overestimated. This assessment is supported by eonventional radiocarbon dates and above＂ all by the glacial chronology developed independently on the basis of the Quaternary geological method. The strongly emerging evidence for a much more extensive LGM glaciation of High Asia is, however, either being ignored or rejected by many authors, solely on the basis of the above-mentioned uncalibrated datings. This self-conceit based on the ＂dating fallacy＂, as we call it, should be avoided since it goes decidedly against the standards of the scientific method established in Quaternary geology and makes a fundamental scientific discussion impossible.展开更多
The late Quaternary paleoceanographic changes in the western Arctic Ocean are revealed by quan- titative studies of foraminiferal abundance, ice-rafted detritus （IRD） and its mineralogical and petrological compositi...The late Quaternary paleoceanographic changes in the western Arctic Ocean are revealed by quan- titative studies of foraminiferal abundance, ice-rafted detritus （IRD） and its mineralogical and petrological compositions, planktonic Neogloboquadrina pachyderma （sin.） （Nps）-δ18O and -δ13C, biogenic and non-biogenic components in Core M03 token from the Chukchi Basin during the Sec- ond Chinese National Arctic Expedition cruise. Seven IRD events appeared at MIS 7, 5, 3 and 1. These IRD were carried in massive icebergs, which were exported to the Beaufort Sea through the M＇Clure Strait Ice Stream, Canadian Arctic Archipelago, and then transported into the Chukchi Basin by the Beaufort Gyre. Low IRD deposition occurred during the glacial times when more extended ice cover and weakened Beaufort Gyre, while the open water condition and the intensified Beaufort Gyre during interglacial periods favored the IRD deposition. Therefore, the IRD events not only indicate the provenance of coarser detritus and ice export events, but also reflect the evolutionary histories of the Beaufort Gyre and North American ice sheet. Seven light Nps-δ18O and -δ13C excursions could respond to enhanced rates of sea ice formation resulting in the pro- duction and sinking of isotopically light brines, but was irrelevant to the warm Atlantic water and freshwater inputs. Whereas, the heavy Nps-δ18O and -δ13C values separately reflect the lessened Arctic freshwater and Pacific water, and well-ventilated surface water from the continental shelf and halocline water. Variations of CaCO3 content and planktonic foraminiferal abundance during the interglacial and glacial periods can demonstrate the incremental or diminishing input of the Atlantic water, while the total organic carbon （TOC） and opal contents increased and decreased during the glacial and interglacial periods, respectively, which could be related to the TOC degradation, opal dissolution and redox conditions of interface between the bottom water and sediments.展开更多
基金financially supported by the National Natural Science Foundation of China(grant No.4157020610)Science and Technology Program of Guizhou Province,China(No.[2017]1407)
文摘Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed greatly.It witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred frequently at a large scale in a very short time,which has thus attracted much attention among geoscientists at home and abroad.
基金Supported by the State Administration of Traditional Chinese Medicine plan projects:Base Construction of Traditional Chinese Medicine Clinical Research(No.JDZX2012129)Shanghai Science and Technology Commitment plan projects:Science and Technology Support Project(No.12401905000)
文摘OBJECTIVE:To explore the characteristics of blood glucose excursions of type 2 diabetes mellitus patients with three different Traditional Chinese Medicine(TCM) syndromes.METHODS:One hundred and nine patients with type 2 diabetes mellitus were recruited from the Department of Endocrinology and the Department of TCM of the Sixth People's Hospital affiliated to Shanghai Jiao Tong University.Subjects were divided into three groups according to TCM syndrome:intrinsic Damp(n- 42),Yin deficiency and internal Heat(n = 25),and Qi and Yin deficiency(n- 42).Subcutaneous interstitial glucose was monitored with a continuous glucose monitoring system for 3consecutive days to investigate the glycemic profile in each group.Plasma C-peptide levels were measured,and an arginine test was taken in 10 patients randomly selected from each group.Glucose data and glycemic variability were analyzed to investigate the differences among the groups.The change in C-peptide levels and the results from arginine trial were used to evaluate β cell function.RESULTS:Indicators reflecting blood glucose level were the highest in subjects with Yin deficiency and internal Heat syndrome,and parameters reflecting glycemic variability were the lowest in those with Qi and Yin deficiency syndrome.The change in C-peptide levels showed that subjects with Qi and Yin deficiency syndrome had the best βcell function among the three groups;this was confirmed by the arginine trial.CONCLUSION:Patients with Qi and Yin deficiency syndrome had a more stable blood glucose profile,as glycemic variability was higher in those with intrinsic Damp syndrome and those with Yin deficiency and internal Heat syndrome.
基金Supported by the National "Eleventh Five-year Plan" for Major Scientific and Technological Research (2006BAI02B08)
文摘Objective:To probe glycemic excursions in type 2 diabetic patients whose hemoglobin A1c(HbA1c) was kept ≤6.0%.Methods:Totally 36 cases with type 2 diabetes(T2DM) with HbA1c≤6.0% and 30 cases with normal glucose tolerance(NGT) from December 2005 to December 2007 in our department were subjected prospectively.Continuous glucose monitoring system(CGMS) was employed to record their continuous blood glucose level for 3 d.The blood glucose profiles including the mean blood glucose(MBG),standard differentiation(SD),mean amplitude of glycemic excursions(MAGE) and absolute means of daily differences(MODD) were analyzed.Results:T2DM group had obviously postprandial hyperglycemia,in about 2 h after meal,especially after breakfast.Fifty-two hypoglycemic episodes occurred during the monitoring period in T2DM groups,of which 73.1%(38 episodes) were absence of symptomatic hypoglycemia with the lowest value of blood glucose only 2.0 mmol/L.And 20 episodes took place during the day hours,while 32 episodes observed during the night hours.Compared with NGT groups,SD,MAGE and MODD were all significantly higher in T2DM groups.MBG was significantly correlated with HbA1c in T2DM groups,but SD,MAGE,NGE and MODD were all independent of HbA1c.MAGE was independent of MODD.Conclusion:The amplitude of glycemic excursions is higher in normol-controlled T2DM groups than the NGT groups.Thus ideally glycemic control is not only to make HbA1c reach standard,but also to lessen glycemic excursions and reduce hypoglycemia episodes.
文摘Vertical excursions allow divers in seafloor habitats to work at depths deeper than thehabitat.Descending excursions from saturation in nitrox have almost all used air as the breathing gas;depth is effectively restricted to less than 60 msw by narcosis and oxygenexposure.The objective is to investigate use of helium mixtures for excursions, taking
基金supported by the National Natural Science Foundation of China(Nos.41672028,41672002,41330101,41221001)
文摘Cambrian carbonates with abundant fossils of agnostoid trilobites deposited on the southern slope （Jiangnan slope belt） of the Yangtze Platform and in the Jiangnan deepwater basin are well exposed in the Wangeun Section of western Hunan, South China, and in the Duibian A Section of western Zhejiang, southeastern China, respectively. To better understand the response of carbonisotope excursions to depositional environment changes, mass extinctions and eustatic events, we collected 530 carbonate samples in fresh roadcut exposures of the two measured sections for analysis of carbon and oxygen isotopic compositions. Data of δ^13C from the Wangcun Section, western Hunan, South China, demonstrate that the Cambrian carbon-isotope profile includes three remarkable positive excursions CPEwc-1, 2, 3 in the Upper Series 2, in the Lower and in the Middle Furongian Series. Three distinctive negative excursions CNEwc,-1, 2, 3 were separately tested in the Lower Terreneuvian Series, Lower Series 3 and in the Upper Furongian Series. Similarly, in the corresponding horizons in the Duibian A Section, Zhejiang Province, southeastern China, three positive excursions CPEdb-1, 2, 3 and three negative excursions CNEdb-1, 2, 3 also have been discovered. We interpret these significant carbon-isotope excursions as being associated with enhanced biogenic prodnctivity, mass extinctions and eustatic events.
基金This work is funded by the National Natural Science Foundation of China(NSFC Grant No.94731010).
文摘Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern China. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.
文摘The Mauna Loa volcano of the Big Island of Hawaii offers the “ad-hoc” lava flows that have recorded the geomagnetic short-term behavior (i.e. excursions) at two key localities such as the younger Kahuku volcanic series (ca. ~41 ka) where 29 flows are exposed for detailed paleomagnetic sampling making up 102 meters of section where the uppermost flow sampled lies directly under the Pahala ash. The second sampling site is the Ninole volcanic series where 25 flows spanning 56 meters of section were also sampled from the northeast and southwest sides of the Kilohana Ridge. The most recent age estimate indicates that the Kahuku flows can correlate well with the transitional/excursional directional results obtained from both volcanic and deep-sea sediments of the global record of the Laschamp (ca. ~41 ka calendar years B.P) excursion and the Ninole flows which are associated to the also global Pringle Fall excursion (ca. 211 ± 13 ka) recorded at the type section.
基金Hubei Provincial Natural Science Foundation of China(Grant No.2025AFA005)Key Research&Development Program of China(Grant No.2019YFA0708400)MOST Special Fund from State Key Laboratory of Geological Processes and Mineral Resources(Grant No.MSFGPMR2025-202)for their financial support。
文摘Atmospheric CO_(2)is a key factor governing Earth's habitability,with its concentration and isotopic variations influenced by both deep and shallow carbon cycles.The Neoproterozoic Era was pivotal for Earth's habitability evolution and global tectonic reorganization,encompassing the assembly-to-breakup of Rodinia and the formation of Gondwana.During this period,marine carbonateδ^(13)C_(PDB)exhibited repeated positive and negative excursions,with the most pronounced negative shift occurring in the Ediacaran(termed the Shuram Excursion,SE).While conventional models attribute SE to organic matter oxidation(due to its13C-depleted signature),this mechanism faces challenges in explaining associated geological features.Notably,the SE event temporally coincides with peak rifting activity and large-scale carbonatite-alkaline magmatism,suggesting a potential deep carbon cycle contribution.Spatial-temporal-compositional correlations imply that tectonic and magmatic processes may play critical roles in carbonateδ^(13)C excursions,necessitating an Earth system approach integrating deep-shallow carbon cycle.Recent studies propose that Neoproterozoicδ^(13)C excursions could originate from deep carbon recycling,with models highlighting subduction-driven decarbonation and melt recycling during supercontinent cycles.These frameworks offer novel insights into the SE enigma.
基金supported by National Science and Technology Major Project (Grant No. 2008ZX05004)Major Project of China National Petroleum Corporation (Grant No. 2008E-0702)
文摘The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a large negative excursion, comparable to ＂BACE＂ （BAsal Cambrian Carbon isotope Excursion） event, which occurs near the Precambrian-Cambrian boundary with a magnitude of 4‰-10‰ （PDB）; （2） the ＂ZHUCE＂ （ZHUjiaqing Carbon isotope Excursion） event, a distinct positive excursion （over 5%0） that can be recognized at the Fortunian Stage to Stage 2 transition; （3） another strong negative one, so-called ＂ROECE＂ （Redlichiid-Olenellid Extinction Carbon isotope Excursion） event, shifting at the interval between Series 2 and Series 3, peaking at -3‰--5‰ （PDB）; （4） the famous Steptoean positive carbon isotope excursion （SPICE）, which has been widely identified at the base of Furongian Series, Paibian Stage, with an amplitude about 4‰ （PDB）. The four sharp σ13C shifts correlate well with coeval paleoceanographic changes and bioevents. Besides, there are some σ13C excursions from a few sections in previous studies, and more data are required to identify whether they are global or regional ones.
文摘Background The accurate and comprehensive assessment of glycemic control in patients with diabetes is important for optimizing glycemic management and for formulating personalized diabetic treatment schemes. This study aimed to analyze the correlation between 1,5-anhydroglucitol （1,5-AG） and glycemic excursions in type 2 diabetic patients. Methods Seventy-one outpatients with type 2 diabetes mellitus were randomly recruited from Chinese People＇s Liberation Army General Hospital. Using a continuous glucose monitoring system （CGMS）, these patients＇ blood glucose levels were monitored for three consecutive days to obtain mean blood glucose （MBG） data. Intraday glycemic excursions were evaluated using the mean amplitude of glycemic excursions （MAGE）, the largest amplitude of glycemic excursions （LAGE）, standard deviation of blood glucose （SDBG） and the M-value. Interday glycemic excursion was assessed by absolute mean of daily difference （MODD）. Postprandial glycemic fluctuations were evaluated using postprandial glucose excursions （PPGE） and postprandial incremental area under the curve （iAUC）. Fasting venous blood samples were collected to measure serum 1,5-AG, whole-blood hemoglobin Alc （HbAlc） and serum glycated albumin （GA）. Clinical markers of glycemia and parameters of glycemic excursions from CGMS were analyzed using the Pearson correlation coefficient and multivariate stepwise regression. Results Pearson correlation analysis revealed that 1,5-AG was significantly correlated with MAGE, SDBG, M-value, LAGE, PPGE and iAUC （r values were-0.509,-0.430,-0.530,-0.462,-0.416 and-0.435, respectively, P 〈0.01）, especially in moderately and well-controlled patients, based on defined HbAlc levels. Multivariate stepwise regression analysis revealed a negative correlation between 1,5-AG and the above parameters, but not HbAlc and GA. Finally, HbAlc and GA were positively correlated with MBG and fasting blood glucose （FBG）. Conclusions 1,5-AG was much better than HbAlc and GA as a marker of glycemic excursions in type 2 diabetic patients. Based on these results 1,5-AG is the best metric for assessing postprandial glucose levels in moderately and well-controlled patients, while HbAlc and GA were superior to 1,5-AG for monitoring MBG and FBG.
基金supported by the Key Research&Development Program of China(2019YFA0708400)the National Natural Science Foundation of China(41530211)+1 种基金MOST(Ministry of Science and Technology)Special Fund from the State Key Laboratory of Geological Processes and Mineral Resources(MSFGPMR01)Australian Research Council(FL180100134)。
文摘The late Ediacaran Shuram Excursion(SE)records the most prominent negativeδ^(13)C excursions(δ^(13)C=-12‰)during Earth’s history.It has been hypothesized to have resulted from oxidation of dissolved organic matter,diagenetic or authigenic precipitates.However,the origin of the SE remains enigmatic;current models face challenges regarding the significant amount of atmospheric oxygen needed to balance such extensive oxidation and sustained inputs of light carbon with extremely negative C isotope compositions.Here,we show that the Doushantuo Formation at the Jiulongwan section in South China,a key stratum recording the SE event,contains mineralogical and geochemical signatures related to igneous processes.Both the occurrence of ankerite,feldspar,moissanite and euhedral quartz in the SE samples and the relatively consistent Ce anomalies of carbonate and O isotopes of quartz indicate a contribution from an igneous source.In particular,the SE samples have trace element and C isotope compositions similar to those of recycled carbonatites formed by decarbonation and melting of sedimentary carbonate rocks.These observations suggest that the deep cycle of ancient carbonate rocks,which were subjected to decarbonation during subduction,melting and eruption related to the breakup of the Rodinia supercontinent,contributed to the SE.This igneous model for the SE may provide a connection between the deep and shallow carbon cycles of the Earth.
基金the National Natural Science Foundation of China(No.10271109).
文摘In this paper, the authors investigate the joint distribution of end points of excursion awayfrom a closed set straddling on a fixed time and use this result to compute the Levy systemand the Dirichlet form of the boundary process.
基金the National Natural Science Foundation of China (Grant No. 49999560) and the State Key Basic Research and Development Plan (Grant No. 2000078502).
文摘High-resolution δ13C records are presented for the Miocene benthic foraminifers Cibici doides wuellerstorfi and C. kullenbergi (24-5 Ma) and the planktonic foraminifer Globigerinoides sacculifer (18-5 Ma) from ODP Site 1148A (18° 50.17′N, 116° 33.93′E, water depth 3308.3 m),northern South China Sea. The general pattern of parallel benthic and planktonic δ13C shows a decrease trend of δ13C values from the early-middle Miocene to the middle-late Miocene. Two dis tinct δ13C positive excursions at 23.1-22.2 and 17.3-13.6 Ma, and two negative excursions at 10.2-9.4 and 6.9-6.2 Ma have been recognized. All these events are cosmopolitan, providing the good data for the stratigraphic correlation of the South China Sea with the global oceans as well as for studying the changes of the global carbon reservoir and its corresponding climate.
文摘Two positive d 13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbon-ate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attrib-uted to enhanced organic carbon burial during the F-F biological mass extinction. However, this worldwide pattern has not been revealed from the well-deposited Late Devonian sequences in southern China. In this paper, a detailed inves-tigation has been made on the Late Devonian section at Dongcun, Guilin, southern China to constrain perturbations in d 13C of carbonates in the F-F deposited sequence. The result from this section also indicates two positive d 13C ex-cursions during the F-F transition. The first excursion with an amplitude of 1.5 occurred at the bottom of linguiformis Zone, later than the early excursion existing in the Late rhe-nana Zone of the Late Devonian profiles in other continents, especially, in central Europe. This difference has been ex-pected to be a result as conodont Palmatolepis linguiformis occurred earlier in southern China than other sites. The second excursion with an amplitude of 2.1 is located at the F-F boundary, same as the records from other continents. This result strongly supports the view that two carbon iso-tope positive excursions during the F-F transition are com-mon in carbonate sediments, resulting from worldwide in-creases of organic carbon burial intensity.
文摘Objective:To evaluate incidence of interscalar excursions between round window (RW) and cochleostomy approaches for cochlear implant (CI) insertion. Methods:This was a retrospective case-comparison. Flat-panel CT (FPCT) scans for 8 CI users with Med-El standard length electrode arrays were collected. Surgical technique was identified by a combination of operative notes and FPCT imaging. Four cochleae underwent round win-dow insertion and 4 cochleae underwent cochleostomy approaches anterior and inferior to the round window. Results:In our pilot study, cochleostomy approaches were associated with a higher likeli-hood of interscalar excursion. Within the cochleostomy group, we found 29% of electrode contacts (14 of 48 electrodes) to be outside the scala tympani. On the other hand, 8.5%of the electrode contacts (4 of 47 electrodes) in the round window insertion group were extra-scalar to the scala tympani. These displacements occurred at a mean angle of occur-rence of 364°±133°, near the apex of the cochlea. Round window electrode displacements tend to localize at angle of occurrences of 400? or greater. Cochleostomy electrodes occurred at an angle of occurrence of 19°e490°.
文摘Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventional M-mode(MM)offers high-resolution imaging but requires precise alignment,which can be diffi cult in ICU patients.[3-5]Anatomical M-mode(AMM)allows flexible line adjustment,enabling accurate DE measurements despite poor acoustic windows.[6]However,comparative data between MM and AMM are limited.This retrospective study evaluated the concordance between MM and AMM for assessing right DE.
文摘Over the past few years, OSL and TCN datings of glacial material from High Asia have come into fashion. To this day, however, these techniques do not permit safe calibration. The intensity of the cosmic ray flux is being modulated by the solar and terrestrial magnetic fields and their secular fluctuations in the past. So far, these variations cannot be converted into the respective local TCN production rates for High Asia. We have reason to believe that the ages that are being calculated despite these uneertainties are generally overestimated. This assessment is supported by eonventional radiocarbon dates and above＂ all by the glacial chronology developed independently on the basis of the Quaternary geological method. The strongly emerging evidence for a much more extensive LGM glaciation of High Asia is, however, either being ignored or rejected by many authors, solely on the basis of the above-mentioned uncalibrated datings. This self-conceit based on the ＂dating fallacy＂, as we call it, should be avoided since it goes decidedly against the standards of the scientific method established in Quaternary geology and makes a fundamental scientific discussion impossible.
基金The National Basic Research Program of China under contract No.G2007CB815903the National Natural Science Foundation of China under contract No.41030859+1 种基金Chinese IPY Program (2007-2009)China Geological Survey projectH[2011]01-14-04
文摘The late Quaternary paleoceanographic changes in the western Arctic Ocean are revealed by quan- titative studies of foraminiferal abundance, ice-rafted detritus （IRD） and its mineralogical and petrological compositions, planktonic Neogloboquadrina pachyderma （sin.） （Nps）-δ18O and -δ13C, biogenic and non-biogenic components in Core M03 token from the Chukchi Basin during the Sec- ond Chinese National Arctic Expedition cruise. Seven IRD events appeared at MIS 7, 5, 3 and 1. These IRD were carried in massive icebergs, which were exported to the Beaufort Sea through the M＇Clure Strait Ice Stream, Canadian Arctic Archipelago, and then transported into the Chukchi Basin by the Beaufort Gyre. Low IRD deposition occurred during the glacial times when more extended ice cover and weakened Beaufort Gyre, while the open water condition and the intensified Beaufort Gyre during interglacial periods favored the IRD deposition. Therefore, the IRD events not only indicate the provenance of coarser detritus and ice export events, but also reflect the evolutionary histories of the Beaufort Gyre and North American ice sheet. Seven light Nps-δ18O and -δ13C excursions could respond to enhanced rates of sea ice formation resulting in the pro- duction and sinking of isotopically light brines, but was irrelevant to the warm Atlantic water and freshwater inputs. Whereas, the heavy Nps-δ18O and -δ13C values separately reflect the lessened Arctic freshwater and Pacific water, and well-ventilated surface water from the continental shelf and halocline water. Variations of CaCO3 content and planktonic foraminiferal abundance during the interglacial and glacial periods can demonstrate the incremental or diminishing input of the Atlantic water, while the total organic carbon （TOC） and opal contents increased and decreased during the glacial and interglacial periods, respectively, which could be related to the TOC degradation, opal dissolution and redox conditions of interface between the bottom water and sediments.
