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The late Early-Paleozoic granitic magmatism in Northwestern Fujian, China: constraints on intraplate orogeny in the South China block
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作者 WanLi Gao ZongXiu Wang 《Acta Geochimica》 EI CAS CSCD 2024年第1期134-149,共16页
The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for ... The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for later tectonic activity.The Wuyi-Yunkai orogenic belt in Southeastern China was extensively exposed to Early Paleozoic magmatism,the genetic mechanism of which remains controversial.To shed light on this issue,detailed petrological,geochemical,and zircon U-Pb-Hf isotopic studies were carried out on two granitoids,namely the Yuntongshan pluton and the Gaoqiao pluton,identified in the central Wuyishan.Zircon U-Pb chronology of the Yuntongshan and Gaoqiao bodies yielded ages of437±4 Ma(MSWD=2.2) and 404±2 Ma(MSWD=12),respectively,indicating that they were emplaced during the Early Silurian and Early Devonian periods.These granitoids are primarily composed of biotite-granite and biotite-monzonitic-granites,with high concentrations of S_(i)O_(2)(73.59-75.91 wt%),K_(2)O+Na_(2)O(8.31-8.73wt%),and low contents of MgO,CaO,Cr,Ni.They are classified as high-K calc-alkaline and weakly metaluminous-strongly peraluminous S-type granites.These granitoids are enriched in light rare earth elements(LREEs) and large ion lithophile elements(LILEs) and depleted in heavy rare earth elements(HREEs) and high field strength elements(HFSEs) with arc affinity.The εHf(t) values of-3.3 to-15.4 with two-stage Hf model ages ranging from 2829 to 1644 Ma,combined with the presence of Neoproterozoic inherited zircons,suggest that the primary magma of these granitoids was derived from the partial melting of Neoproterozoic crust with a Paleoproterozoic crustal model age.These findings,combined with the spatio-temporal distribution of regional magmatism,reveal that the late Early-Paleozoic granitoids formed in the intraplate orogenic background originating from the subduction of the proto-Tethys Ocean and proto-Pacific Ocean around the margin of the east Gondwana supercontinent. 展开更多
关键词 late Early-Paleozoic GRANITES Intraplate orogeny Cathysian block Zircon U-Pb-Hf Isotopic composition
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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene
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作者 Dongqin HUANG Xiaolong LI +6 位作者 Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期772-786,共15页
A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare e... A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change. 展开更多
关键词 Yongjiang River estuary sedimentary organic matter LIGNIN environmental change late Pleistocene
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Early proactive monitoring of DNA-thioguanine in patients with Crohn’s disease predicts thiopurine-induced late leucopenia in NUDT15/TPMT normal metabolizers
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作者 Ting Yang Kang Chao +9 位作者 Xia Zhu Xue-Ding Wang Sumyuet Chan Yan-Ping Guan Jing Mao Pan Li Shao-Xing Guan Wen Xie Xiang Gao Min Huang 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1751-1763,共13页
BACKGROUND Thiopurine-induced leucopenia significantly hinders the wide application of thiopurines.Dose optimization guided by nudix hydrolase 15(NUDT15)has significantly reduced the early leucopenia rate,but there ar... BACKGROUND Thiopurine-induced leucopenia significantly hinders the wide application of thiopurines.Dose optimization guided by nudix hydrolase 15(NUDT15)has significantly reduced the early leucopenia rate,but there are no definitive biomarkers for late risk leucopenia prediction.AIM To determine the predictive value of early monitoring of DNA-thioguanine(DNATG)or 6-thioguanine nucleotides(6TGN)for late leucopenia under a NUDT15-guided thiopurine dosing strategy in patients with Crohn’s disease(CD).METHODS Blood samples were collected within two months after thiopurine initiation for detection of metabolite concentrations.Late leucopenia was defined as a leukocyte count<3.5×10^(9)/L over two months.RESULTS Of 148 patients studied,late leucopenia was observed in 15.6%(17/109)of NUDT15/thiopurine methyltransferase(TPMT)normal and 64.1%(25/39)of intermediate metabolizers.In patients suffering late leucopenia,early DNATG levels were significantly higher than in those who did not develop late leucopenia(P=4.9×10^(-13)).The DNATG threshold of 319.43 fmol/μg DNA could predict late leucopenia in the entire sample with an area under the curve(AUC)of 0.855(sensitivity 83%,specificity 81%),and in NUDT15/TPMT normal metabolizers,the predictive performance of a threshold of 315.72 fmol/μg DNA was much more remarkable with an AUC of 0.902(sensitivity 88%,specificity 85%).6TGN had a relatively poor correlation with late leucopenia whether in the entire sample(P=0.021)or NUDT15/TPMT normal or intermediate metabolizers(P=0.018,P=0.55,respectively).CONCLUSION Proactive therapeutic drug monitoring of DNATG could be an effective strategy to prevent late leucopenia in both NUDT15/TPMT normal and intermediate metabolizers with CD,especially the former. 展开更多
关键词 Thiopurine-induced late leucopenia DNA-thioguanine 6-thioguanine nucleotide Proactive therapeutic drug monitoring Crohn’s disease
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Impaired implicit emotion regulation in patients with panic disorder:An event-related potential study on affect labeling
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作者 Hai-Yang Wang Li-Zhu Li +2 位作者 Yi Chang Xiao-Mei Pang Bing-Wei Zhang 《World Journal of Psychiatry》 SCIE 2024年第2期234-244,共11页
BACKGROUND Panic disorder(PD)involves emotion dysregulation,but its underlying mechanisms remain poorly understood.Previous research suggests that implicit emotion regulation may play a central role in PD-related emot... BACKGROUND Panic disorder(PD)involves emotion dysregulation,but its underlying mechanisms remain poorly understood.Previous research suggests that implicit emotion regulation may play a central role in PD-related emotion dysregulation and symptom maintenance.However,there is a lack of studies exploring the neural mechanisms of implicit emotion regulation in PD using neurophysiological indicators.AIM To study the neural mechanisms of implicit emotion regulation in PD with eventrelated potentials(ERP).METHODS A total of 25 PD patients and 20 healthy controls(HC)underwent clinical evaluations.The study utilized a case-control design with random sampling,selecting participants for the case group from March to December 2018.Participants performed an affect labeling task,using affect labeling as the experimental condition and gender labeling as the control condition.ERP and behavioral data were recorded to compare the late positive potential(LPP)within and between the groups.RESULTS Both PD and HC groups showed longer reaction times and decreased accuracy under the affect labeling.In the HC group,late LPP amplitudes exhibited a dynamic pattern of initial increase followed by decrease.Importantly,a significant group×condition interaction effect was observed.Simple effect analysis revealed a reduction in the differences of late LPP amplitudes between the affect labeling and gender labeling conditions in the PD group compared to the HC group.Furthermore,among PD patients under the affect labeling,the late LPP was negatively correlated with disease severity,symptom frequency,and intensity.CONCLUSION PD patients demonstrate abnormalities in implicit emotion regulation,hampering their ability to mobilize cognitive resources for downregulating negative emotions.The late LPP amplitude in response to affect labeling may serve as a potentially valuable clinical indicator of PD severity. 展开更多
关键词 Panic disorder IMPLICIT Emotion regulation Affect labeling late positive potential
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Clinical characteristics of patients with early-and late-onset optic neuromyelitis optica spectrum disease
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作者 LI Fei LIU Ting +5 位作者 Yang Yi-hao LIN Hui-xia TONG jing-yi LI Zong-jun LIANG Bin-ji LI Qi-fu 《Journal of Hainan Medical University》 CAS 2024年第2期14-19,共6页
Objective:To analyze the different clinical features of patients with early-onset(EO-NMOSDs)and late-onset neuromyelitis optica spectrum diseases(LO-NMOSDs).Methods:A total of 51patients with neuromyelitis optica spec... Objective:To analyze the different clinical features of patients with early-onset(EO-NMOSDs)and late-onset neuromyelitis optica spectrum diseases(LO-NMOSDs).Methods:A total of 51patients with neuromyelitis optica spectrum disease who were diagnosed in our hospital for the first time from January 2015 to December 2022 were included in the First Affiliated Hospital of Hainan Medical College and divided into 22 cases in the EO-NMOSDs group and 29 cases in the LO-NMOSDs group according to whether the age of onset was 50 years old.The basic data,Extended Disability Status Scale(EDSS)score,blood and cerebrospinal fluid test indicators of the two groups were statistically analyzed.Results:There were no significant differences in demographic characteristics,clinical features and serum AQP-4 antibody positivity rate between the two groups(all P>0.05),and there were significant differences in triglycerides(TG),low-density lipoprotein(LDL),apolipoprotein A(APOA),apolipoprotein B(APOB)and lipoprotein a(P=0.010,P=0.048,P=0.014,P=0.061,P=0.001,respectively),and cerebrospinal fluid LDH,There were significant differences between microprotein quantification and EDSS score(P=0.018,P=0.034,P=0.025,respectively),and the level of microprotein quantification in cerebrospinal fluid of LO-NMOSDs had a certain correlation with the degree of disability(r=0.52,P<0.03).Conclusion:LO-NMOSDs and EO-NMOSDs group patients have similar demographic characteristics,serum AQP-4 antibody positive rate and clinical features,but compared with EO-NMOSDs,patients in LO-NMOSDs group are prone to abnormal lipid metabolism,higher trace proteins in cerebrospinal fluid and more likely to be disabled,and among LO-NMOSDs,the higher the trace protein in the cerebrospinal fluid,the more severe the disability status of patients. 展开更多
关键词 Optic neuromyelitis optica spectrum DISORDERS late onset Cerebrospinal fluid microprotein quantification EDSS score
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A Comparison between Late Preterm and Term Infants with Respiratory Distress Syndrome, Early-Onset Sepsis, and Neonatal Jaundice in Ecuadorian Newborns
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作者 Teresa Altamirano Molina 《Open Journal of Pediatrics》 2024年第1期22-35,共14页
Background: To examine the differences in prevalence of respiratory distress syndrome, early-onset sepsis and jaundice, between late preterm infants versus term infants in Ecuadorian newborns. Methods: Study design: E... Background: To examine the differences in prevalence of respiratory distress syndrome, early-onset sepsis and jaundice, between late preterm infants versus term infants in Ecuadorian newborns. Methods: Study design: Epidemiological, observational, and cross-sectional, with two cohorts of patients. Settings: IESS Quito Sur Hospital at Quito, Ecuador, from February to April of 2020. Participants: This study included 204 newborns, 102 preterm infants, 102 term infants. Results: There are significant differences between late preterm infants and term infants, with a p-value of 0.000 in the prevalence of early sepsis, 70.59% vs. 35.29%. In respiratory distress syndrome between late and term premature infants, significant differences were observed with a p-value of 0.000, the proportion being 55.58% vs. 24.51% respectively. The prevalence of jaundice is higher in term infants with a p value of 0.002, 72.55%, versus 51.96% in late preterm infants, and the mean value of bilirubins in mg/dL was higher in term infants 14.32 versus 12.33 in late preterm infants;this difference is statistically significant with a p value of 0.004. Admission to the NICU is more frequent in late preterm infants with a p-value of 0.000, being 42.16% for late preterm infants vs. 7.84% in term infants;the mean of the hospital days with p-value 0.005, was higher in late preterm infants 4.97 days vs. 3.55 days for term newborns. Conclusion: Due to the conditions of their immaturity, late preterm infants are 2.86 times more likely to present early sepsis than full-term newborns. It is shown that late preterm infants are 2.69 times more likely to have respiratory distress syndrome compared to term infants, therefore, late preterm infants have a longer hospital stay of 4.97 days versus 3.55 days in term infants. Jaundice and mean bilirubin levels are higher in term infants due to blood group incompatibility and insufficient breastfeeding. 展开更多
关键词 late Preterm Term Newborn Respiratory Distress Syndrome Early Onset Sepsis JAUNDICE
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Tracheostomy-related data from an intensive care unit for two consecutive years before the COVID-19 pandemic
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作者 Maria Papaioannou Evdoxia Vagiana +4 位作者 Serafeim-Chrysovalantis Kotoulas Maria Sileli Katerina Manika Alexandros Tsantos Nikolaos Kapravelos 《World Journal of Methodology》 2024年第2期75-87,共13页
BACKGROUND Tracheostomy is commonly used in intensive care unit(ICU)patients who are expected to be on long-term mechanical ventilation or suffer from emergency upper airway obstruction.However,some studies have confl... BACKGROUND Tracheostomy is commonly used in intensive care unit(ICU)patients who are expected to be on long-term mechanical ventilation or suffer from emergency upper airway obstruction.However,some studies have conflicting findings regarding the optimal technique and its timing and benefits.AIM To provide evidence of practice,characteristics,and outcome concerning tracheostomy in an ICU of a tertiary care hospital.METHODS This was a retrospective cohort study including adult critical care patients in a single ICU for two consecutive years.Patients’demographic characteristics,severity of illness(APACHE II score),level of consciousness[Glasgow Coma Scale(GCS)],comorbidities,timing and type of tracheostomy procedure performed and outcome were recorded.We defined late as tracheostomy placement after 8 days or no tracheotomy.RESULTS Data of 660 patients were analyzed(median age of 60 years),median APACHE II score of 19 and median GCS score of 12 at admission.Tracheostomy was performed in 115 patients,of whom 63 had early and 52 late procedures.Early tracheostomy was mainly executed in case of altered level of consciousness and severe critical illness polyneuromyopathy,however there were no significant statistical results(47.6%vs 36.5%,P=0.23)and(23.8%vs 19.2%,P=0.55)respectively.Regarding the method selected,early surgical tracheostomy(ST)was conducted in patients with maxillofacial injuries(50.0%vs 0.0%,P=0.033),whereas late surgical tracheostomy was selected for patients with goiter(44.4%vs 0.0%P=0.033).Patients with early tracheostomy spent significantly fewer days on mechanical ventilation(15.3±8.5 vs 22.8±9.6,P<0.001)and in ICU in general(18.8±9.1 vs 25.4±11.5,P<0.001).Percutaneous dilatation tracheostomy(PDT)vs ST was preferable in older critical care patients in the case of Central Nervous System underlying cause of admission(62.5%vs 26.3%,P=0.004).ST was the method of choice in compromised airway(31.6%,vs 7.3%P=0.008).A large proportion of patients(88/115)with tracheostomy managed to wean from mechanical ventilation and were transferred out of the ICU(100%vs 17.4%,P<0.001).CONCLUSION PDT was performed more frequently in our cohort.This technique did not affect mechanical ventilation days,ventilator-associated pneumonia(VAP),ICU length of stay,or survival.No complications were observed in the percutaneous or surgical tracheostomy groups.Patients undergoing early tracheostomy benefited in terms of mechanical ventilation days and ICU length of stay but not of discharge status,presence of VAP,or survival. 展开更多
关键词 TRACHEOSTOMY Early tracheostomy late tracheostomy Percutaneous dilatation tracheostomy Surgical tracheostomy WEANING Survival Mechanical ventilation
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Trajectory of Walking Function in Late-Stage Older Individuals Managed with a Regular Exercise Program: A 5-Year Longitudinal Tracking with an IoT Gait Analysis System Using Accelerometers
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作者 Taisuke Ito 《Open Journal of Therapy and Rehabilitation》 2024年第2期174-184,共11页
Purpose: This study focused on maintaining and improving the walking function of late-stage older individuals while longitudinally tracking the effects of regular exercise programs in a day-care service specialized fo... Purpose: This study focused on maintaining and improving the walking function of late-stage older individuals while longitudinally tracking the effects of regular exercise programs in a day-care service specialized for preventive care over 5 years, using detailed gait function measurements with an accelerometer-based system. Methods: Seventy individuals (17 male and 53 female) of a daycare service in Tokyo participated in a weekly exercise program, meeting 1 - 2 times. The average age of the participants at the start of the program was 81.4 years. Gait function, including gait speed, stride length, root mean square (RMS) of acceleration, gait cycle time and its standard deviation, and left-right difference in stance time, was evaluated every 6 months. Results: Gait speed and stride length improved considerably within six months of starting the exercise program, confirming an initial improvement in gait function. This suggests that regular exercise programs can maintain or improve gait function even age groups that predictably have a gradual decline in gait ability due to enhanced age. In the long term, many indicators tended to approach baseline values. However, the exercise program seemingly counteracts age-related changes in gait function and maintains a certain level of function. Conclusions: While a decline in gait ability with aging is inevitable, establishing appropriate exercise habits in late-stage older individuals may contribute to long-term maintenance of gait function. 展开更多
关键词 late-Stage Elderly Exercise Gait Function ACCELEROMETER IoT-Based Gait Analysis Device
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The Immediate Analgesic Effect and Impact on Gait Function of Transcutaneous Electrical Nerve Stimulation in Late-Stage Elderly Individuals with Knee Pain: Examination of Gait Function Using an IoT-Based Gait Analysis Device
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作者 Taisuke Ito 《Open Journal of Therapy and Rehabilitation》 2024年第2期185-195,共11页
Purpose: This study verified the effects of transcutaneous electrical nerve stimulation (TENS), which can be worn during walking and exercise, in elderly individuals with late-stage knee pain who exercise regularly. M... Purpose: This study verified the effects of transcutaneous electrical nerve stimulation (TENS), which can be worn during walking and exercise, in elderly individuals with late-stage knee pain who exercise regularly. Methods: Thirty-two late-stage elderly individuals were evaluated for knee pain during rest, walking, and program exercises, with and without TENS. Gait analysis was performed using an IoT-based gait analysis device to examine the effects of TENS-induced analgesia on gait. Results: TENS significantly reduced knee pain during rest, walking, and programmed exercises, with the greatest analgesic effect observed during walking. The greater the knee pain without TENS, the more significant the analgesic effect of TENS. A comparison of gait parameters revealed a significant difference only in the gait cycle time, with a trend towards faster walking with TENS;however, the effect was limited. Conclusion: TENS effectively relieves knee pain in late-stage elderly individuals and can be safely applied during exercise. Pain management using TENS provides important insights into the implementation of exercise therapy in this age group. 展开更多
关键词 late-Stage Elderly Knee Joint Pain Exercise Transcutaneous Electrical Stimulation IoT-Based Gait Analysis Device
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Predictors of early and late hepatocellular carcinoma recurrence 被引量:14
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作者 Riccardo Nevola Rachele Ruocco +10 位作者 Livio Criscuolo Angela Villani Maria Alfano Domenico Beccia Simona Imbriani Ernesto Claar Domenico Cozzolino Ferdinando Carlo Sasso Aldo Marrone Luigi Elio Adinolfi Luca Rinaldi 《World Journal of Gastroenterology》 SCIE CAS 2023年第8期1243-1260,共18页
Hepatocellular carcinoma(HCC)is the most frequent liver neoplasm,and its incidence rates are constantly increasing.Despite the availability of potentially curative treatments(liver transplantation,surgical resection,t... Hepatocellular carcinoma(HCC)is the most frequent liver neoplasm,and its incidence rates are constantly increasing.Despite the availability of potentially curative treatments(liver transplantation,surgical resection,thermal ablation),long-term outcomes are affected by a high recurrence rate(up to 70%of cases 5 years after treatment).HCC recurrence within 2 years of treatment is defined as“early”and is generally caused by the occult intrahepatic spread of the primary neoplasm and related to the tumor burden.A recurrence that occurs after 2 years of treatment is defined as“late”and is related to de novo HCC,independent of the primary neoplasm.Early HCC recurrence has a significantly poorer prognosis and outcome than late recurrence.Different pathogenesis corresponds to different predictors of the risk of early or late recurrence.An adequate knowledge of predictive factors and recurrence risk stratification guides the therapeutic strategy and post-treatment surveillance.Patients at high risk of HCC recurrence should be referred to treatments with the lowest recurrence rate and when standardized to combined or adjuvant therapy regimens.This review aimed to expose the recurrence predictors and examine the differences between predictors of early and late recurrence. 展开更多
关键词 Hepatocellular carcinoma Early recurrence late recurrence PREDICTORS Liver transplant Liver resection Thermal ablation
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Late sowing enhances lodging resistance of wheat plants by improving the biosynthesis and accumulation of lignin and cellulose 被引量:2
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作者 DONG Xiu-chun QIAN Tai-feng +4 位作者 CHU Jin-peng ZHANG Xiu LIU Yun-jing DAI Xing-long HE Ming-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1351-1365,共15页
Delayed sowing mitigates lodging in wheat. However, the mechanism underlying the enhanced lodging resistance in wheat has yet to be fully elucidated. Field experiments were conducted to investigate the effects of sowi... Delayed sowing mitigates lodging in wheat. However, the mechanism underlying the enhanced lodging resistance in wheat has yet to be fully elucidated. Field experiments were conducted to investigate the effects of sowing date on lignin and cellulose metabolism, stem morphological characteristics, lodging resistance, and grain yield. Seeds of Tainong 18,a winter wheat variety, were sown on October 8(normal sowing) and October 22(late sowing) during both of the 2015–2016 and 2016–2017 growing seasons. The results showed that late sowing enhanced the lodging resistance of wheat by improving the biosynthesis and accumulation of lignin and cellulose. Under late sowing, the expression levels of key genes(Ta PAL, Ta CCR, Ta COMT, TaCAD, and TaCesA1, 3, 4, 7, and 8) and enzyme activities(TaPAL and TaCAD) related to lignin and cellulose biosynthesis peaked 4–12 days earlier, and except for the TaPAL, TaCCR, and TaCesA1 genes and TaPAL, in most cases they were significantly higher than under normal sowing. As a result, lignin and cellulose accumulated quickly during the stem elongation stage. The mean and maximum accumulation rates of lignin and cellulose increased, the maximum accumulation contents of lignin and cellulose were higher, and the cellulose accumulation duration was prolonged. Consequently, the lignin/cellulose ratio and lignin content were increased from 0 day and the cellulose content was increased from 11 days after jointing onward. Our main finding is that the improved biosynthesis and accumulation of lignin and cellulose were responsible for increasing the stem-filling degree, breaking strength, and lodging resistance. The major functional genes enhancing lodging resistance in wheat that are induced by delayed sowing need to be determined. 展开更多
关键词 CELLULOSE late SOWING LIGNIN LODGING resistance wheat
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Geochronology,Petrogenesis and Tectonic Setting of the Late Jurassic I-type Granites in the North Qinling Orogenic Belt,Central China 被引量:2
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作者 HUANG Yanna LI Dunpeng +1 位作者 XIAO Aifang XU Songming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1132-1149,共18页
The North Qinling Orogenic Belt(NQOB)is a composite orogenic belt in central China.It started evolving during the Meso-Neoproterozoic period and underwent multiple stages of plate subduction and collision before enter... The North Qinling Orogenic Belt(NQOB)is a composite orogenic belt in central China.It started evolving during the Meso-Neoproterozoic period and underwent multiple stages of plate subduction and collision before entering intra-continental orogeny in the Late Triassic.The Meso-Cenozoic intra-continental orogeny and tectonic evolution had different responses in various terranes of the belt,with the tectonic evolution of the middle part of the belt being particularly controversial.The granites distributed in the Dayu and Kuyu areas in the middle part of the NQOB can provide an important window for revealing the geodynamic mechanisms of the NQOB.The main lithology of Dayu and Kuyu granites is biotite monzogranite,and the zircon U-Pb dating yielded intrusive ages of 151.3±3.4 Ma and 147.7±1.5 Ma,respectively.The dates suggest that the biotite monzogranite were formed at the end of the Late Jurassic.The whole-rock geochemistry analysis shows that the granites in the study areas are characterized by slightly high SiO_(2)(64.50-68.88 wt%)and high Al_(2)O_(3)(15.12-16.24 wt%)and Na_(2)O(3.55-3.80 wt%)contents.They are also enriched in light rare earth elements,large ion lithophile elements(e.g.,Ba,K,La,Pb and Sr),and depleted in high field strength elements(HFSEs)(e.g.,Ta,Nb,P and Ti).Additionally,the granites have weakly negative-slightly positive Eu anomalies(δEu=0.91-1.19).Zircon Lu-Hf isotopic analysis showedε_(Hf)(t)=-6.1--3.8,and the two-stage model age is T_(2DM(crust))=1.5-1.6 Ga.The granites in the study areas are analyzed as weak peraluminous high-K calc-alkaline I-type granites.They formed by partial melting of the thickened ancient lower crust,accompanied by the addition of minor mantle-derived materials.During magma ascent,they experienced fractional crystallization,with residual garnet and amphibole for a certain proportion in the magma source region.Comprehensive the geotectonic data suggest that the end of the Late Jurassic granite magmatism in the Dayu and Kuyu areas represents a compression-extension transition regime.It may have been a response to multiple tectonic mechanisms,such as the late Mesozoic intra-continental southward subduction of the North China Craton and the remote effect of the Paleo-Pacific Plate subduction. 展开更多
关键词 partial melting tectonic transition I-type granite late Jurassic North Qinling Orogenic Belt
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Petrogenesis of the Late Eocene to Early Oligocene Yao'an Shoshonitic Complex,Southeastern Tibet:Partial Melting of an Ancient Continental Lithospheric Mantle beneath the Yangtze Block 被引量:2
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作者 DONG Mengmeng YANG Tiannan +3 位作者 XUE Chuandong XIN Di LIANG Mingjuan YAN Qinggao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1657-1670,共14页
Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the C... Cenozoic potassic-ultrapotassic igneous rocks are widespread in the southeastern Tibetan Plateau.Their petrogenesis and magmatic processes remain subject to debate in spite of numerous publications.Almost all of the Cenozoic extrusive and intrusive rocks in the Yao’an area,western Yunnan Province,SW China,are geochemically shoshonitic,collectively termed here the Yao’an Shoshonitic Complex(YSC).The YSC is located in the(south)easternmost part of the ENE-WSW-trending,~550 km-long and~250 km-wide Cenozoic magmatic zone;the latter separates the orthogonal and oblique collision belts of the India-Eurasia collision orogen.Previously published geochronological and thermochronological data revealed that the rocks of the YSC were emplaced over a short timespan of 34-32 Ma.This and our new data suggest that the primary magma of the YSC likely was formed by partial melting of ancient continental lithospheric mantle beneath the Yangtze Block.This part of the continental lithospheric mantle had likely not been modified by any oceanic subduction.Fractionation crystallization of an Mg-and Ca-bearing mineral and TiFe oxides during the magmatic evolution probably account for the variable lithologies of the YSC. 展开更多
关键词 Ancient continental lithospheric mantle Partial melting Yao’an Shoshonitic Complex late Eocene to early Oligocene SE Tibetan Plateau
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Palynological Evidence of Late Pleistocene Soft-sediment Deformation Event in the Northeastern Margin of the Tibetan Plateau 被引量:1
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作者 WEI Lijie LI Zhenhong +3 位作者 DONG Xiaopeng CUI Jiawei HUANG Ting KOU Linlin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期841-854,共14页
The northeastern margin of the Tibetan Plateau is the youngest part of the Tibetan Plateau where tectonic activity is intense and climate change is complex.In this study,combined with field investigations,we explored ... The northeastern margin of the Tibetan Plateau is the youngest part of the Tibetan Plateau where tectonic activity is intense and climate change is complex.In this study,combined with field investigations,we explored accelerator mass spectrometry 14C and optically stimulated luminescence dating and palynological analysis of the sedimentary sequence in the Qingshuihe Basin to explain the origin of soft-sediment deformation layer.Dating and palynological results from the Sanchahe section in the basin revealed a detailed history of vegetation variation and associated climate change from~18 to~5 ka BP.The results indicate that the permafrost developed at~18–11.7 ka BP,and the soft-sediment deformation structures formed at~11.7–5 ka BP.Together with the characteristics of the deformation(meter-scale,continuous symmetrical wave)and paleoclimate,we suggest that the soft-sediment deformation layer in the late Pleistocene was cryoturbated under climatic conditions.The discovery of a series of cryoturbations in the Qingshuihe Basin has further enriched the regional distribution of periglacial phenomena in the west of the Ordos Plateau,expanded the distribution range of periglacial phenomena,and provided evidence for exploring the temporal and spatial changes in permafrost in northern China at the end of the late Pleistocene. 展开更多
关键词 cryoturbation palynological analysis late Pleistocene Qingshuihe Basin Tibetan Plateau
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Late Jurassic Volcanism Deduced from Geochemical,Geochronological,and Sr-Nd-Hf Isotopic Composition Characteristics of the Nanyuan Formation,South China 被引量:1
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作者 WANG Dongsheng LI Jinwen +3 位作者 SHE Hongquan WANG Kunming YANG Junzhi REN Chenghao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期449-468,共20页
The Nanyuan Formation contains information related to the Mesozoic tectonic transformation.In this study,three representative profiles were surveyed from the Nanyuan Formation,and multiple analyses were conducted.Zirc... The Nanyuan Formation contains information related to the Mesozoic tectonic transformation.In this study,three representative profiles were surveyed from the Nanyuan Formation,and multiple analyses were conducted.Zircon U-Pb dating yielded their ages as approximately 158–146 Ma.The volcanic rocks are enriched in Rb,Th,U,K,and Pb and depleted in Nb,Ta,P,and Ti,implying their affinity for I-type granites.TheεNd(t)values(-8.3 to-6.0),^(87)Sr/^(86)Sr)i values(0.7077–0.7094)of the volcanic rock,andεHf(t)values(-8.71 to 0.12)of the Mesozoic zircons suggest that the Nanyuan Formation magma originated in the lower crust with the involvement of depleted mantle materials.The parent rocks of the rhyolitic and dacitic volcanic rocks formed by partial melting of basement rocks in South China and the andesitic volcanic rocks were derived from partial melting of the metasomatites generated by slab-mantle interaction.The fractional crystallization also played an important role in later stage.Discrimination diagrams of the volcanic rocks indicated that they formed in a volcanic arc environment.Combined with previous data,the Nanyuan Formation recorded subduction of the Paleo-Pacific Plate before regional tectonic transformation.The compressive stress field endured until the end of the Late Jurassic. 展开更多
关键词 late Jurassic Nanyuan Formation volcanic rocks volcanic arc geochemistry PETROGENESIS Pinghe
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Late spring cold reduces grain number at various spike positions by regulating spike growth and assimilate distribution in winter wheat
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作者 Feifei Lin Cheng Li +8 位作者 Bo Xu Jian Chen Anheng Chen Muhammad A.Hassan Binbin Liu Hui Xu Xiang Chen Jianqiang Sun Jincai Li 《The Crop Journal》 SCIE CSCD 2023年第4期1272-1278,共7页
Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses o... Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield. 展开更多
关键词 WHEAT late spring cold Dry matter accumulation Cell wall invertase Grain number Yield
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Fast tracking alien gene discovery by molecular markers in a late flowering Chinese cabbage-cabbage translocation line‘AT7–4'
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作者 Hui Li Aixia Gu +12 位作者 Daling Feng Na Li Rui Yang Xinpei Zhang Shuangxia Luo Umer Karamat Qianyun Wang Shuxin Xuan Xueping Chen Yin Lu Yanhua Wang Shuxing Shen Jianjun Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第1期89-97,共9页
Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained seve... Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding objective.In our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage genes.Cabbage-specific molecular markers show that these genes were coming from chromosome C01 of cabbage.In this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the offspring.Consequently,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week vernalization.Based on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were developed.This study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines. 展开更多
关键词 Chinese cabbage Translocation line Alien gene Molecular marker late flowering
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The sedimentary record of the Sanshui Basin:Implication to the Late Cretaceous tectonic evolution in the northern margin of South China Sea
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作者 Zhe ZHANG Nianqiao FANG Zhen SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期532-549,共18页
Whether the South China continental margin had shifted from active subduction to passive extension in the Late Cretaceous remains controversial.Located in the northernmost of the South China Sea continental margin,San... Whether the South China continental margin had shifted from active subduction to passive extension in the Late Cretaceous remains controversial.Located in the northernmost of the South China Sea continental margin,Sanshui Basin developed continuous stratigraphy from Lower Cretaceous to Eocene and provides precious outcrops to study the regional tectonic evolution during the Cretaceous.Therefore,we conducted field observations,petrology,clay mineralogy,geochemistry,and detrital zircon chronology analyses of sedimentary rocks from the Upper Cretaceous Sanshui Formation in Sanshui Basin.Results suggest that the Sanshui Basin is characterized as an intermoutane basin with multiple provenances,strong hydrodynamic environment,and proximal accumulation in the Late Cretaceous.An angular unconformity at the boundary between the Lower and Upper Cretaceous was observed in the basin.The sedimentary facies of the northern basin changed from lacustrine sedimentary environment in the Early Cretaceous to alluvial facies in the Late Cretaceous.The zircon U-Pb ages of granitic gravelly sandstone from Sanshui Formation prominently range from 100 Ma to 300 Ma,which is close to the deposition age of Sanshui Formation.The major and trace elements of the Late Cretaceous sedimentary samples show characteristics of active continental margin,and are different from the Paleogene rifting sequences.Hence,we propose that the northern South China Sea margin underwent an intense tectonic uplift at the turn of the Early and Late Cretaceous(around 100 Ma).Afterward,the northern South China Sea margin entered a wide extension stage in the Late Cretaceous(~100 to~80 Ma).This extensional phase is related to the back-arc extension in the active continental margin environment,which is different from the later passive rifting in the Cenozoic.The transition from active subduction to passive extension in the northern South China Sea may occur between the late Late Cretaceous and the Paleogene. 展开更多
关键词 continental margin South China Sea Sanshui Basin late Cretaceous tectonic transition
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Late Holocene glacier variations indicated by theδ18O of ice core enclosed gaseous oxygen in the central Tibetan Plateau
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作者 LI Jiu-le XU Bai-qing +2 位作者 WANG Ning-lian YAO Ping XU Xiang-ke 《Journal of Mountain Science》 SCIE CSCD 2023年第2期325-337,共13页
Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar regions.Yet,less is known about its climatic implication in the mountainous glaciers as the lack of contin... Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar regions.Yet,less is known about its climatic implication in the mountainous glaciers as the lack of continuous record.Here,we present a long-term,continuousδ18Obub record from the Tanggula glacier in the central Tibetan Plateau(TP).Based on comparisons of its variation with regional climate and glacier changes,we found that there was a good correlation between the variation of theδ18Obub in this alpine ice core and the accumulation and melting of this glacier.The more developed the firn layer on glacier surface,the more positive theδ18Obub.Conversely,the more intense the glacier melting,the more negative theδ18Obub.Combined with the chronology of ice core enclosed gases,the glacier variations since the late Holocene in the central TP were reconstructed.The result showed that there were four accumulation and three deficit periods of glaciers in this region.The strongest glacier accumulation period was 1610-300 B.C.,which corresponds to the Neoglaciation.The most significant melting period was the last 100 years,which corresponds to the recent global warming.The Medieval Warm Period was relatively significant in the central TP.However,during the Little Ice Age,there was no significant glacier accumulation in the central TP,and even short deficit events occurred.Comparisons of the late Holocene glacier variation in the central TP with glacier and climate variations in the TP and the Northern Hemisphere showed that it was closely related to the North Atlantic Oscillation. 展开更多
关键词 Ice core air bubble Stable isotope ratio Gaseous oxygen Glacier variation late Holocene Tibetan Plateau
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Late presentation of dural tears:Two case reports and review of literature
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作者 Chang Xu Rong-Peng Dong +1 位作者 Xue-Liang Cheng Jian-Wu Zhao 《World Journal of Clinical Cases》 SCIE 2023年第11期2464-2473,共10页
BACKGROUND The late presentation of dural tears(LPDT)has a low incidence rate and hidden symptoms and is easily ignored in clinical practice.If the disease is not treated in time,a series of complications may occur,in... BACKGROUND The late presentation of dural tears(LPDT)has a low incidence rate and hidden symptoms and is easily ignored in clinical practice.If the disease is not treated in time,a series of complications may occur,including low intracranial pressure headache,infection,pseudodural cyst formation,and sinus formation.Here,we describe two cases of LPDT.CASE SUMMARY Two patients had sudden fever 1 wk after lumbar surgery.Physical examination showed obvious tenderness in the operation area.The patients were confirmed as having LPDT by lumbar magnetic resonance imaging and surgical exploration.One case was caused by continuous negative pressure suction and malnutrition,and the other was caused by decreased dural ductility and low postoperative nutritional status.The first symptom of both patients was fever,with occasional headache.Both patients underwent secondary surgery to treat the LPDT.Dural defects were observed and dural sealants were used to seal the dural defects,then drainage tubes were retained for drainage.After the operation,the patients were treated with antibiotics and the patients’surgical incisions healed well,without fever or incision tenderness.Both recovered and were discharged 1 wk after the operation.CONCLUSION LPDT is a rare complication of spinal surgery or neurosurgery that has hidden symptoms and can easily be overlooked.Since it may cause a series of complic-ations,LPDT needs to be actively addressed in clinical practice. 展开更多
关键词 late presentation of dural tears Delayed cerebrospinal fluid leakage Dural repair FACTORS Clinical management Case report
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