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Organic petrographic investigation for artificially matured marine shale:Insights from anhydrous pyrolysis of Upper Ordovician shale from the Baltic Basin,Lithuania
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作者 Ye Wang Zhong-Liang Ma +6 位作者 Nan-Sheng Qiu Bao-Jian Shen Xiao-Min Xie Tenger Borjigin Lun-Ju Zheng Zhao-Xi Zuo An-Yang Pan 《Petroleum Science》 2025年第7期2677-2698,共22页
The absence of humic vitrinite complicates the determination of thermal maturity in pre-Devonian sediments.Lower Paleozoic shales contain structured zooclasts,solid bitumen,and vitrinite-like materials,and their refle... The absence of humic vitrinite complicates the determination of thermal maturity in pre-Devonian sediments.Lower Paleozoic shales contain structured zooclasts,solid bitumen,and vitrinite-like materials,and their reflectances have been found to be valid maturity proxies.Yet there remains much controversy as to the degree of evolution of reflectances.The current work aims to investigate the reflectance of dispersed organic matter(DOM),as well as their transformation degree and organic pore development.To this end,this study evaluated an Upper Ordovician zooclasts-bearing shale and a Middle Jurassic coal sample via anhydrous-pyrolysis to compare differences in the maturation pathways between marine-derived DOM and terrigenous vitrinite.These two original samples were cut into small blocks and placed in an identical vacuum stainless vessel simultaneously.The pyrolysis was carried out at isothermal temperatures ranging from 250 to 550℃ for 48 h.The morphologic and reflectance changes of DOM in pyrolysis residues were studied and compared with previous pyrolysis results.Adopting the combined use of optical reflectance and scanning electron microscope(SEM)techniques,the study shows that DOM in the shale components consists of solid bitumen(SB),bituminite,chitinozoans,a few graptolites,vitrinite-like particles(VLP),alginate and liptodetrinite.The reflectance sequence,from high to low,is zooclasts,VLP and SB.Their reflectances gradually increases as the pyrolysis temperature rises,although the rate of growth is slower than that of co-heating coal vitrinite.Notably,zooclasts yield significantly higher reflectance values than those of VLP and SB at each pyrolysis temperature.However,the VLP undergoes two distinct phases in reflectance development,despite gradual morphology changes similar to vitrinite.Based on evidence of the optical texture and organic pore evolution,we argue that a fair amount of VLP in studied Upper Ordovician shale does not consist of graptolite-type fragments.Consequently,the VLPRo serves as a reliable indicator for assessing organic matter maturity in Ordovician shales with a reflectance value of less than 2.0%.This investigation enhances scholarly understandings of marine-derived DOM evolution issues,providing clearer correlations among reflectances of different DOM and reducing uncertainties in thermal maturity determination. 展开更多
关键词 Thermal maturity Vitrinite-like particle Zooclast Anhydrous pyrolysis Equivalent vitrinite reflectance Organic pore
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Static aerobic composting of municipal sewage sludge with forced ventilation:Using matured compost as bulking conditioner 被引量:5
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作者 欧阳建新 施周 +3 位作者 钟华 刘卫 柴琦 袁兴中 《Journal of Central South University》 SCIE EI CAS 2014年第1期303-309,共7页
Static aerobic composting of municipal sewage sludge with forced ventilation or air ventilation using matured compost as bulking conditioner was investigated. Physical and chemical parame ,eters, e.g., temperature, mo... Static aerobic composting of municipal sewage sludge with forced ventilation or air ventilation using matured compost as bulking conditioner was investigated. Physical and chemical parame ,eters, e.g., temperature, moisture content, VSS, CODcr, pH, and germination index (GI), were analyzed to characterize the composting process. Fermentation starts quickly in both forced and air ventilation compost heaps and reaches high-temperature stage after 2 d, owing to the bulking function of matured compost. Compared to air ventilation, however, forced ventilation enables the high-temperature stage to last longer for approximately 7 d. The moisture content of both compost bodies decreases from 62% to about 50% as a result of evaporation, and it decreases slightly faster in forced ventilation compost heap after 13 d due to the higher temperature and better ventilation condition. Although no obvious differences of VSS and pH are observed between both compost heaps, the soluble CODcr and GI show differences during the second half period of fermentation. In forced ventilation compost, the soluble CODcr has a small rebound after 13 d, and GI decreases from 46% to 35% but then increases. These results show that in general, the matured compost is a good conditioner and force ventilation with a proper air supply strategy can be more efficient than air ventilation. 展开更多
关键词 municipal sewage sludge static aerobic composting forced ventilation matured compost bulking conditioner
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EXPRESSING HUMAN MATURED BRAIN-DERIVED NEUROTROPHIC FACTOR GENE IN E.Coli AND DETERMINING ITS BIOACTIVITY 被引量:1
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作者 马东亮 任惠民 +3 位作者 胡海涛 刘勇 杨广笑 王全颖 《Academic Journal of Xi'an Jiaotong University》 2001年第1期9-12,共4页
Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expr... Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expression vector plasmid pBV220. The ligation products were used to transform the competent E. Coli DH5a. The proteins or mBDNF were experessed by temperature inducing. The expression products were dealed with solubilizing inclusion bodies and refolding protein. It was introduced into the embryonic chicken DRG to test whether the expressed mBDNF is a biologically active protein. Results The recombinant plasmid pBV/mBDNF was success- fully constructed. By temperature inducing, under the control of the bacteriophage λPL promoter, the experessed mBDNF protein was a 14Kd non-fusion protein,which existed in E. Coli as inclusion bodies. The size or expressed mBDNF is identical to the prediction. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of embryonic 8-day-old chicken DRG neurons as compared to control. Conclusion Tke mBDNF gene can be expressed bioactively in E. Coli. 展开更多
关键词 human matured brain-derived neurotrophic factor (mBDNF) molecular subcloning EXPRESSION bioactivity
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THE INSEMINATION OF GOLDFISH(CARASSIUM AURATUS) OOCYTE MATURED IN VITRO 被引量:1
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作者 王壬学 吴贤汉 +4 位作者 周晶 张士璀 马英杰 吴尚懃 史瀛仙 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1991年第1期88-93,共6页
Full maturation of goldfish oocyte was induced in vitro by 17 a-hydroxy-20B-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal vesicle breakdown (GVBD). In the... Full maturation of goldfish oocyte was induced in vitro by 17 a-hydroxy-20B-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal vesicle breakdown (GVBD). In the experiment, incubation duration for GVBD varied in different broods of oocytes. Generally, if the duration for GVBD was shorter than 6 h, oocytes would have a better chance to survive after maturation and insemination. The maturation of nucleus (GV) and cytoplasm are not synchronous. Cytoplasm maturation occurs several hs after GVBD. Oocytes inseminated 8-9 h after GVBD have the highest fertilizing and hatching rate. Fertilized ova matured in vitro can develop to sexually mature adults capable of reproduction. 展开更多
关键词 maturation migration mature OOCYTE INSEMINATION PERIPHERY chance CYTOPLASM INCUBATION varied
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Fertilization of in vitro matured human oocytes by intracytoplasmic sperm injection (ICSI) using ejaculated and testicular spermatozoa 被引量:1
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作者 TingFengt JuanChen Ling-BoCai Jia-YinLiu Yun-DongMao WeiDing 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第1期39-43,共5页
Aim: To evaluate the fertilization competence of spermatozoa from ejaculates and testicle when the oocytes were matured in vitro following intracytoplasmic sperm injection (ICSI). Methods: Fifty-six completed cycles i... Aim: To evaluate the fertilization competence of spermatozoa from ejaculates and testicle when the oocytes were matured in vitro following intracytoplasmic sperm injection (ICSI). Methods: Fifty-six completed cycles in 46 women with polycystic ovarian syndrome were grouped according to the semen parameters of their male partners. Group 1 was 47 cycles that presented motile and normal morphology spermatozoa in ejaculates and Group 2 was the other nine cycles where male partners were diagnosed as obstructive azoospermia and spermatozoa could only be found in testicular tissue fragment. All female patients received minimal stimulation with gonadotropin. Immature oocytes were matured in vitro and inseminated by ICSI. The spermatozoa from testes were retrieved by testicular fine needle aspiration. Results: A total of 449 and 78 immature oocytes were collected and cultured for 48 hours, 75.5 % (339/449) and 84.6 % (66/78) oocytes were matured in Groups 1 and 2, respectively. The percentage of oocytes achieving normal fertilization was significantly higher in Group 1 than that in Group 2 (72.9 % vs. 54.5 %, P < 0.05). There were no significant differences in the rates of oocytes cleavage and clinical pregnancies in these two groups [87.4 % (216/247) vs. 88.9 % (32/36); 21.3 % (10/47) vs. 44.4 % (4/9)]. A total of 15 babies in the two groups were healthy delivered at term. Conclusion: It appears that IVM combined with ICSI using testicular spermatozoa can produce healthy infants, while the normal fertilization rate of in vitro matured oocytes after ICSI using testicular spermatozoa was significantly lower than using the ejaculated spermatozoa. 展开更多
关键词 intracytoplasmic sperm injection immature human oocytes in vitro maturation testicular fine needle sperm aspirations
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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Restoration of hydrocarbon generation potential of the highly mature Lower Cambrian Yuertusi Formation source rocks in the Tarim Basin 被引量:2
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作者 Yao Hu Cheng-Zao Jia +6 位作者 Jun-Qing Chen Xiong-Qi Pang Lin Jiang Chen-Xi Wang Hui-Yi Xiao Cai-Jun Li Yu-Jie Jin 《Petroleum Science》 2025年第2期588-606,共19页
The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Pa... The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Paleozoic.However,its hydrocarbon generation and evolution characteristics and resource potential have long been constrained by deeply buried strata and previous research.In this paper,based on the newly obtained ultra-deep well drilling data,the hydrocarbon generation and expulsion model ofЄ_(1)y shale was established by using data-driven Monte Carlo simulation,upon which the hydrocarbon generation,expulsion,and retention amounts were calculated by using the diagenetic method.The research indicates that theЄ_(1)y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×10^(10)t,the cumulative hydrocarbon expulsion is 35.59×10^(10)t,and the cumulative residual hydrocarbon is 33.29×10^(10)t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ_(1)y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ_(1)y is the most significant source rock contributing to the marine oil and gas resources in the Tarim Basin,filling the gap in hydrocarbon expulsion calculation in the study area,and providing an important basis for the formation and distribution of Paleozoic hydrocarbon reservoirs.The prospect of deep ultra-deep oil and gas exploration in the Tarim Basin is promising.Especially,the large area of dolomite reservoirs under the Cambrian salt and source rock interiors are the key breakthrough targets for the next exploration in the Tarim Basin. 展开更多
关键词 Evaluation of resource potential Highly mature hydrocarbon source rocks Yuertusi formation Tarim Basin
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Development and identification of wheat-Psathyrostachys huashanica 7NsS small segment translocation lines with early heading date gene Ehd-7Ns 被引量:1
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作者 Binwen Tan Jing Gao +13 位作者 Zhijun Yao Wei Zhu Lili Xu Yiran Cheng Yi Wang Jian Zeng Xing Fan Lina Sha Haiqin Zhang Peng Qin Yinghui Li Yonghong Zhou Dandan Wu Houyang Kang 《The Crop Journal》 2025年第4期1186-1196,共11页
Psathyrostachys huashanica Keng ex P.C.Kuo(2n=2x=14,NsNs),a wild relative of wheat,represents a valuable germplasm resource for genetic improvement of wheat.We previously confirmed that a chromosome 7Ns from P.huashan... Psathyrostachys huashanica Keng ex P.C.Kuo(2n=2x=14,NsNs),a wild relative of wheat,represents a valuable germplasm resource for genetic improvement of wheat.We previously confirmed that a chromosome 7Ns from P.huashanica carries genes that accelerate heading and maturity in wheat.Here,we developed three small segment translocation lines(T7NsS-2BL 2BS,T7NsS-1AS 1AL#1,and T7NsS-1AS 1AL#2)along with one additional small segment translocation line(T7NsS-7BS 7BL)through^(60)Co-γ irradiation,identified using genomic in situ hybridization(GISH),fluorescence in situ hybridization(FISH),and liquid chip array analyses.Our findings demonstrated that chromosome 7NsS contained a major early heading date gene,tentatively designated Ehd-7Ns,which was mapped to an approximate31.45 Mb region,corresponding to the short arm of wheat chromosome 7A(IWGSC RefSeq v1.0).The T7NsS-1AS 1AL#2 line exhibited no significant yield penalty and possessed superior agronomic traits relative to the other translocation lines in the field,making it a promising pre-breeding donor for breeding early maturing wheat.Furthermore,21 specific Kompetitive Allele Specific PCR(KASP)markers were developed based on transcriptome data,enabling effective tracing of alien chromosomal segments carrying this source of Ehd-7Ns in marker-assisted breeding.Collectively,these newly developed translocation lines and specific KASP markers will facilitate the transfer and utilization of favorable genes from P.huashanica chromosome 7Ns in future wheat breeding programs. 展开更多
关键词 Early maturity KASP markers Marker assisted selection Wheat breeding
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Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report
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作者 Saori Kondo Takashi Suzuki +4 位作者 Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi 《World Journal of Clinical Cases》 SCIE 2025年第1期56-61,共6页
BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a ... BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life. 展开更多
关键词 Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report
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The validity of automatic methods for estimating maturation stage in young athletes:A comparison of the Maturo smartphone application and sport science expert evaluations
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作者 Ximing Shang Jorge Arede +1 位作者 Pedro Couto Nuno Leite 《Journal of Sport and Health Science》 2025年第4期32-39,共8页
Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biologica... Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biological maturity and the limitations of existing testing methods, particularly in adolescent sports contexts, there is a pressing need for a non-invasive method that is convenient, accurate, and broadly applicable to monitor the biological maturity of adolescent athletes comprehensively. In response to this need, a maturity assessment method based on the smartphone application Maturo has been developed. This study evaluates the accuracy and validity of the Maturo software, an automated tool for estimating biological age and related maturation metrics.Methods: A sample of 103 actively training teenage athletes aged 9-17 years. The sample included 76 males(age = 11.74 ± 1.55 years, mean ±SD) and 27 females(age = 13.95 ± 1.40 years), all without medical conditions that might impact growth or development.Results: Compared to traditional expert evaluations, the intraclass correlation coefficients(ICCs) and Pearson correlation coefficients demonstrated reliable positive correlations and significant agreement between the Maturo software and expert methods across multiple metrics, such as biological age(ICC = 0.965, R = 0.97), corrected biological age(ICC = 0.973, R = 0.99), predicted adult height(ICC = 0.991, R = 0.99), and percentage of adult height achieved(ICC = 0.955, R = 0.97). The Bland-Altman plots provided additional evidence of the validity of the Maturo software estimations, showing low systematic error in most measures. The linear regression analysis produced excellent adjusted R2values: 0.95for biological age and 0.99 for anticipated adult height. The Maturo approach demonstrated a high level of dependability in classifying teenagers into groups based on their maturity status and timing. The κ coefficients of 0.93 for maturity status and 0.82 for maturity timing indicate a nearly perfect agreement with the expert technique.Conclusion: While the Maturo software's non-invasive nature, cost-effectiveness, and ease of use could make it a potential tool for regular monitoring of growth and maturation in young athletes, its promising results in assessing maturation should be interpreted with caution due to limitations such as sample size and demographic constraints. Further longitude research with larger and more diverse populations is needed to validate these preliminary findings and strengthen the evidence for its broader applicability. 展开更多
关键词 Maturation assessment Youth athletes Maturo software Biological maturation estimation ANTHROPOMETRY
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Designing a Comprehensive Data Governance Maturity Model for Kenya Ministry of Defence
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作者 Gilly Gitahi Gathogo Simon Maina Karume Josphat Karani 《Journal of Information Security》 2025年第1期44-69,共26页
The study aimed to develop a customized Data Governance Maturity Model (DGMM) for the Ministry of Defence (MoD) in Kenya to address data governance challenges in military settings. Current frameworks lack specific req... The study aimed to develop a customized Data Governance Maturity Model (DGMM) for the Ministry of Defence (MoD) in Kenya to address data governance challenges in military settings. Current frameworks lack specific requirements for the defence industry. The model uses Key Performance Indicators (KPIs) to enhance data governance procedures. Design Science Research guided the study, using qualitative and quantitative methods to gather data from MoD personnel. Major deficiencies were found in data integration, quality control, and adherence to data security regulations. The DGMM helps the MOD improve personnel, procedures, technology, and organizational elements related to data management. The model was tested against ISO/IEC 38500 and recommended for use in other government sectors with similar data governance issues. The DGMM has the potential to enhance data management efficiency, security, and compliance in the MOD and guide further research in military data governance. 展开更多
关键词 Data Governance Maturity Model Maturity Index Kenya Ministry of Defence Key Performance Indicators Data Security Regulations
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Genome-wide circular RNAs signatures involved in sexual maturation and its heterosis in chicken
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作者 Yuanmei Wang Jingwei Yuan +10 位作者 Yanyan Sun Aixin Ni Jinmeng Zhao Yunlei Li Panlin Wang Lei Shi Yunhe Zong Pingzhuang Ge Shixiong Bian Hui Ma Jilan Chen 《Journal of Integrative Agriculture》 2025年第2期697-711,共15页
Sexual maturation heterosis has been widely exploited in animal crossbreeding.However,the underlying mechanism has been rarely explored in chicken.In the present study,we performed the reciprocal crossing between Whit... Sexual maturation heterosis has been widely exploited in animal crossbreeding.However,the underlying mechanism has been rarely explored in chicken.In the present study,we performed the reciprocal crossing between White Leghorn and Beijing You chicken to evaluate the phenotypes related to sexual maturation,and profiled the ovary circRNAs of purebreds(WW,YY)and crossbreds(WY,YW)to elucidate the molecular mechanism underlying heterosis for sexual maturation.Pubic space and oviduct length exhibited positive heterosis,and age at first egg(AFE)exhibited negative heterosis in the crossbreds.We identified 3,025 known circRNAs and 624 putative circRNAs,which were mainly derived from the exons.Among these circRNAs,141 and 178circRNAs were specially expressed in WY and YW,respectively.There were 52.38 and 64.63%of total circRNAs in WY and YW exhibited non-additive expression pattern,respectively.GO enrichment and KEGG pathway analysis showed that the host genes of non-additive circRNAs were mainly involved in TGF-beta signaling pathway,oocyte development,ATPase activator activity,oocyte meiosis,progesterone-mediated oocyte maturation and GnRH signaling pathway.Weighted gene co-expression network analysis identified that 4 modules were significantly(P<0.05)correlated with oviduct length and pubic space.The host genes of non-additive circRNAs harbored in the 4 modules were associated with MAPK signaling pathway and Wnt signaling pathway.Furthermore,competing endogenous RNAs(ceRNA)network analysis characterized non-additive circRNAs gal-FGFR2_0005 and galMAPKAP1_0004 could interact with gga-miR-1612 and gga-miR-12235-5p to regulate CNOT6,COL8A1,and FHL2,which were essential for ovary development,indicating that the non-additive circRNAs involved in the formation of sexual maturation heterosis through regulating genes related to the reproductive and developmental process.The findings would provide a deeper understanding of the molecular mechanism underlying sexual maturation heterosis from a novel perspective. 展开更多
关键词 CHICKEN sexual maturation HETEROSIS OVARY circRNA
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Petroleum system,filling history and age appraisal of source rocks of the Niger Delta Basin:Fingerprinting of pentacyclic triterpenoids
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作者 Timothy Chibuike Anyanwu Bassey Offiong Ekpo 《Energy Geoscience》 2025年第2期331-341,共11页
Gas chromatography-mass spectrometry(GC-MS)was used to analyze the pentacyclic triterpenoid distributions,specifically hopane and oleanane fingerprints,in 24 crude oil samples from the Niger Delta depobelts,with the a... Gas chromatography-mass spectrometry(GC-MS)was used to analyze the pentacyclic triterpenoid distributions,specifically hopane and oleanane fingerprints,in 24 crude oil samples from the Niger Delta depobelts,with the aim of defining the petroleum system,filling history,and the age of source rock producing these oils.The results indicate that the Niger Delta oils belong to a single fluvio-deltaic petroleum system,reflecting similar source organic facies and depositional environments.Geochemical parameters,including C29/C30hopane ratios,oleanane index,Ts/Tm,(Ts/(Ts+Tm)),moretane/C30hopane ratios,and C3222S/(22S+22R)ratios,suggest oxic conditions during source rock deposition and thermal maturity of the oils.The presence of terrigenous organic matter and complex filling history are also evident and influenced by multiple phases of sedimentation,and petroleum generation.A comparative plot of geologic time(Paleogene-Neogene age)and oleanane percentage composition show that the crude oils are constrained to the chronostratigraphic ages of their respective depobelts,demonstrating the potential of oleanane-derived parameters for relative dating of hydrocarbon sources,complementing traditional index fossil methods. 展开更多
关键词 OLEANANE Petroleum system Depositional history MATURITY Depobelts Niger delta
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Wnt2bb signaling promotes pharyngeal chondrogenic precursor proliferation and chondrocyte maturation by activating Yap expression in zebrafish
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作者 Xiaojuan Guo Liping Yang +4 位作者 Yujie Wang Mengna Yuan Wenqing Zhang Xinyu He Qiang Wang 《Journal of Genetics and Genomics》 2025年第2期220-230,共11页
Pharyngeal cartilage morphogenesis is crucial for the formation of craniofacial structures.Cranial neural crest cells are specified at the neural plate border,migrate to pharyngeal arches,and differentiate into pharyn... Pharyngeal cartilage morphogenesis is crucial for the formation of craniofacial structures.Cranial neural crest cells are specified at the neural plate border,migrate to pharyngeal arches,and differentiate into pharyngeal chondrocytes,which subsequently flatten,elongate,and stack like coins during maturation.Although the developmental processes prior to chondrocyte maturation have been extensively studied,their subsequent changes in morphology and organization remain largely elusive.Here,we show that wnt2bb is expressed in the pharyngeal ectoderm adjacent to the chondrogenic precursor cells in zebrafish.Inactivation of Wnt2bb leads to a reduction in nuclearβ-catenin,which impairs chondrogenic precursor proliferation and disrupts chondrocyte morphogenesis and organization,eventually causing a severe shrinkage of pharyngeal cartilages.Moreover,the decrease ofβ-catenin in wnt2bb^(-/-)mutants is accompanied by the reduction of Yap expression.Reactivation of Yap can restore the proliferation of chondrocyte progenitors as well as the proper size,shape,and stacking of pharyngeal chondrocytes.Our findings suggest that Wnt/β-catenin signaling promotes Yap expression to regulate pharyngeal cartilage formation in zebrafish. 展开更多
关键词 Wnt/β-catenin signaling YAP Wnt2bb Chondrocyte maturation Pharyngeal cartilage ZEBRAFISH
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Natural variation of ClCCT promoter promotes flowering and dwarfing in adlay(Coix lacryma-jobi L.)
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作者 Jieliang Bao Yanan Wang +11 位作者 Kuoshu Cui Xiangdong Li Hong Pan Chaoyuan Shi Xiang Yan Jinglin Wang Xiaotong Wang Qing Dou Xiaolong Dong Yibing Yuan Shufeng Zhou Chao Guo 《The Crop Journal》 2025年第3期942-951,共10页
The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countrie... The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countries.However,the currently planted varieties are all semi-domesticated landraces with delayed flowering and excessive height.These defects limit yield improvement per unit area and mechanized harvesting.In this study,a major QTL associated with flowering time and plant height in adlay has been mapped and identified as Cl CCT,a gene having a conserved function and regulatory pathway for inhibiting flowering time and increasing plant height in gramineous crops.Among the six identified haplotypes of Cl CCT,the haplotype with 38-bp insertion in promoter region of Cl CCT has earlier flowering time and wider geographical distribution than other haplotypes.The insertion variation,which arises from the segmental duplication of Cl CCT,can inhibit the expression level of reporter gene and has been used in breeding for early maturity and dwarfing.These research results not only reinforce our understanding of the importance of CCT domain protein in the tropical crops adapting to high-latitude environment,but also provide a validated breeding target for the early maturity and dwarfing of adlay. 展开更多
关键词 Early maturity DWARFING CCT domain Convergent selection Genome duplication event
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Stable carbon isotope compositions of individual light hydrocarbons in oils: New indicator of source facies and maturity
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作者 Donglin Zhang Meijun Li Rongzhen Qiao 《Geoscience Frontiers》 2025年第5期455-469,共15页
Light hydrocarbons(LHs)are key components of petroleum,and the carbon isotopes composition(δ^(13)C)of individual LHs contains a wealth of geochemical information.Forty-four oil samples from five different basins were... Light hydrocarbons(LHs)are key components of petroleum,and the carbon isotopes composition(δ^(13)C)of individual LHs contains a wealth of geochemical information.Forty-four oil samples from five different basins were analyzed using gas chromatography(GC),gas chromatography-mass spectrometry(GC–MS),and gas chromatography-isotope ratio mass spectrometry(GC-IRMS).Theδ^(13)C values of forty-three LHs were recognized and determined by comparing the GC and GC-IRMS methods.The results revealed significant differences inδ^(13)C distribution characteristics among different LH compounds.Theδ^(13)C variation of individual LHs in iso-paraffins showed the widest range,followed by cycloalkanes and aromatics,whereas theδ^(13)C variation in n-paraffins showed the narrowest range.Theδ^(13)C values of most individual LHs are primarily affected by the source facies and thermal evolution.Among them,c-1,3-dimethylcyclohexane(c-1,3DMCH)is mainly sourced from higher plants but may also form through abiotic mechanisms such as catalysis or cyclization.Theδ^(13)C values of c-1,3DMCH(δ^(13)Cc-1,3DMCH)primarily exhibit parental genetic characteristics,enabling effective distinction of oil from different source facies.Specifically,theδ^(13)Cc-1,3DMCH in marine oils,lacustrine oils,terrigenous oils,and coal-formed oils are<–22‰,from–22‰to−20.2‰,from−20.2‰to−18.4‰,and>−18.4‰,respectively.Moreover,maturity is the primary controlling factor forδ^(13)C values of 3MC7(δ^(13)C3MC7,3MC7:3-methylheptane),while the source facies serve as a secondary influence.The plot ofδ^(13)Cc-1,3DMCH andδ^(13)C3MC7 was introduced to classify source facies.Asδ^(13)Cc-1,3DMCH andδ^(13)C3MC7 increase,the source facies transits from marine to lacustrine,then terrigenous,and finally coal facies.Additionally,increasingδ^(13)C3MC7 indicates a relative increase in maturity.Therefore,theδ^(13)Cc-1,3DMCH vs.δ^(13)C3MC7 plot serves as an effective tool for distinguishing source facies and assessing relative maturity. 展开更多
关键词 Light hydrocarbons Individual carbon isotope Source facies MATURITY
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Toward Digital Technology Maturity:Empowering Small Medium Enterprise in Sleman Yogyakarta Indonesia Toward Sustainable Tourism and Creative Economy Development
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作者 Ayu Helena Cornellia Robertus Saptoto Kamila Salsabela 《Journalism and Mass Communication》 2025年第2期98-112,共15页
In the era of global tourism and creative economies,digital technology maturity has emerged as a critical factor for the sustainable development of small and medium enterprises(SMEs)in Indonesia.This research is imple... In the era of global tourism and creative economies,digital technology maturity has emerged as a critical factor for the sustainable development of small and medium enterprises(SMEs)in Indonesia.This research is implemented to find out current digital technology maturity levels among SMEs in the subdistrict of Cangkringan,district of Sleman,Yogyakarta,Indonesia,highlighting their role in fostering sustainable tourism and creative economic growth.Using a mixed-method approach,the research combines qualitative insights from in-depth interviews with three local government representatives and Focus Group Discussion with 15 SMEs in the area.Additionally,a quantitative analysis of SMEs across various sectors,including crafts and culinary services,supports the study’s conclusions.The finding reveals a significant gap between government’s training programs and the digital literacy of SMEs as well as a lack of affordable technological resources which could impede the full realization of digital benefits.Strengthening digital technology maturity among SMEs is essential for enhancing their competitiveness and long-term sustainability,yielding both financial and non-financial benefits.This also contributes to find out digital literacy gaps,impact on competitiveness and sustainability,policy and stakeholder recommendations,and government action.These insights offer valuable guidance for policymakers and stakeholders striving to support the digital transformation of SMEs in similar settings.The study also sheds light on digital literacy gaps,their impact on competitiveness and offers policy recommendations for government and stakeholders to address these challenges such as through government and community collaboration. 展开更多
关键词 digital technology maturity SMES sustainable tourism creative economy
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Accelerating Hydrocarbon Maturation: The Role of Metals and Unconventional Resources in the Northeast Java Basin
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作者 Bagus Sapto Mulyatno Muh Sarkowi +4 位作者 Ordas Dewanto Asep Irawan Suharso Andy Setyo Wibowo Indra Mamad Gandidi 《Energy Engineering》 2025年第8期3099-3116,共18页
Rising global energy needs have intensified the search for unconventional hydrocarbon sources,especially in under-selected areas like the Northeast Java Basin.This region harbors promising unconventional hydrocarbon r... Rising global energy needs have intensified the search for unconventional hydrocarbon sources,especially in under-selected areas like the Northeast Java Basin.This region harbors promising unconventional hydrocarbon reserves,where source rocks function as dual-phase systems for both hydrocarbon generation and storage.This research investigates how metal-based catalysts,particularly iron(Fe),can expedite hydrocarbon maturation in such reservoirs.Combining well logging,geochemical assessments,seismic data,and advanced lab techniques,including X-ray Diffraction(XRD),we pinpoint optimal zones for exploration.Results indicate that the Tuban,Kujung,and Ngimbang formations contain economically viable unconventional deposits,exhibiting tight reservoir properties(permeability:0.01–1 md)and moderate to good Total Organic Carbon(TOC)levels(1%–2%).Spatial analysis reveals elevated density concentrations in the northern sector,indicative of high-viscosity hydrocarbons typical of unconventional plays.Crucially,Fe additives were found to markedly enhance organic matter conversion,shortening maturation periods and boosting hydrocarbon yield.XRD data confirms that Fe alters crystalline configurations,increasing reactivity and speeding up thermal breakdown(shifting immature organic compounds toward maturity at an accelerated rate).These findings contribute to the evolving discourse on unconventional resource exploitation by proposing an innovative recovery enhancement strategy.The study also sets a precedent for investigating metal-assisted hydrocarbon conversion in geologically comparable basins globally. 展开更多
关键词 Unconventional hydrocarbons hydrocarbon maturation metal catalysis geochemical analysis
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ABA-activated subclassⅢSnRK2s control kernel maturation in maize
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作者 Yayun Wang Tiandan Long +8 位作者 Aying Qin Qiang Liao Hao Wang Junjie Zhang Hanmei Liu Yinghong Liu Yufeng Hu Yubi Huang Yangping Li 《The Crop Journal》 2025年第3期777-791,共15页
Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known ... Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known regulatory network that modulate seed maturation in Arabidopsis;however,the underlying genetic and regulatory mechanisms in cereal crops remain largely unknown.Here,we found that ABA levels exhibited two distinct peaks during kernel development in maize,corresponding to the lag and maturation phase,respectively.Integrated transcriptome and proteome profiling of kernels treated with exogenous ABA at the pre-maturation stage suggested that the second peak of ABA acts as a trigger for kernel maturation program.Knockout of ZmSnRK2s demonstrated that subclassⅢZmSnRK2s are required for kernel maturation in maize,and the loss-of-function of subclassⅢZmSnRK2s showed a disruption in kernel dehydration and dormancy.We identified a conserved ABA–SnRK2–b ZIP signaling pathway mediating this process in maize.Additionally,ZmSnRK2.10 overexpression accelerates kernel dehydration during maturity,achieving reduced kernel moisture content(KMC)at physiological maturity(PM).Overall,our findings establish ABA-activated SnRK2s as central regulators of kernel maturation in maize and provide valuable genetic resources for breeding maize varieties with low moisture content at harvest. 展开更多
关键词 Seed maturation ABA SubclassⅢZmSnRK2s Maize kernel KMC
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Design and synthesis of novel saponin-triazole derivatives in the regulation of adipogenesis
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作者 Yongsheng Fang Zhiyun Zhu +7 位作者 Chun Xie Dazhen Xia Huimin Zhao Zihui Wang Qian Lu Caimei Zhang Wenyong Xiong Xiaodong Yang 《Chinese Journal of Natural Medicines》 2025年第8期920-931,共12页
Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduce... Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduced pharmacological efficacy.This study synthesized and evaluated 36 saponin-1,2,3-triazole derivatives of ginsenosides Rg1/Rb1 and notoginsenoside R1 for anti-adipogenesis activity in vitro.The research revealed that the ginsenosides Rg1-1,2,3-triazole derivative a17 demonstrates superior adipogenesis inhibitory effects.Structure-activity relationships(SARs)analysis indicates that incorporating an amidyl-substituted 1,2,3-triazole into the saponin side chain via Click reaction enhances anti-adipogenesis activity.Additionally,several other derivatives exhibit general adipogenesis inhibition.Compound a17 demonstrated enhanced potency compared to the parent ginsenoside Rg1.Mechanistic investigations revealed that a17 exhibits dose-dependent inhibition of adipogenesis in vitro,accompanied by decreased expression of preadipocytes.Peroxisome proliferator-activated receptorγ(PPARγ),fatty acid synthase(FAS),and fatty acid binding protein 4(FABP4)adipogenesis regulators.These findings establish the ginsenoside Rg1-1,2,3-triazole derivative a17 as a promising adipocyte differentiation inhibitor and potential therapeutic agent for obesity and associated metabolic disorders.This research provides a foundation for developing effective therapeutic approaches for various metabolic syndromes. 展开更多
关键词 Panax notoginseng Saponin-triazole derivatives Adipocyte differentiation and maturation Lipid metabolism Structure-activity relationships
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