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Least Squares Model Averaging Based on Generalized Cross Validation

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 495-509页

作者： xin-min li Guo-hua ZOU xin-yu ZHANG Shang-wei ZHAO School of Mathematics and Statistics Qingdao UniversityQingdao 266071China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Beijing Academy of Artificial Intelligence Beijing 100084China College of Science Minzu University of ChinaBeijing 100081China

Frequentist model averaging has received much attention from econometricians and statisticians in recent years.A key problem with frequentist model average estimators is the choice of *** paper develops a new approach of choosing weights based on an approximation of generalized cross *** resultant least squares model average estimators are proved to be asymptotically optimal in the sense of achieving the lowest possible squared ***,the optimality is built under both discrete and continuous weigh *** with the existing approach based on Mallows criterion,the conditions required for the asymptotic optimality of the proposed method are more *** studies and real data application show good performance of the proposed estimators.

关键词： asymptotic optimality frequentist model averaging generalized cross validation mallows criterion

Fetal cell microchimerism in the maternal mouse spinal cord

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Neuroscience Bulletin 2014年第1期30卷 81-89页

作者： Guohui Zhang Yunan Zhao xin-min li Jiming Kong Department of Forensic Medicine Hebei North University Department of Human Anatomy and Cell Science Faculty of Medicine University of Manitoba Department of Psychiatry University of Manitoba

Fetal cell microchimerism refers to the persistence of fetal cells in the maternal tissues following pregnancy. It has been detected in peripheral organs and the brain, but its existence in the spinal cord has not been reported. Our aim was to detect fetal cell microchimerism in the spinal cord of maternal mice. C57BL/6 female mice were crossed with GFP transgenic male mice and sacrificed after their first or third delivery. GFP-positive cells, which were presumably from fetuses whose fathers were GFP transgenic, were detected in the spinal cord by fluorescence microscopy and immunohistochemistry. PCR was also performed to detect GFP DNA, which must come from GFP hemizygous fetuses. We found GFP-positive cells and detectable GFP DNA in most of the maternal spinal cords. Twenty percent （1/5） of the mice that were only pregnant once had detectable fetal cells, while 80% （4/5） of those that were pregnant three times had detectable fetal cells. Some fetal cells, which not only emitted green fluorescence but also expressed NeuN, were detected in the spinal cords from maternal mice. These results indicate that fetal cells migrate into the spinal cord of a maternal mouse during and/or after the gestational period, and the fetal cells may differentiate into neurons in the spinal cord.

关键词： fetal cell microchimerism greenfluorescent protein spinal cord mouse

Activation of canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cell line WB-F344 in vitro

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World Journal of Gastroenterology 2008年第43期14卷 6673-6680页

作者： Ying Zhang xin-min li Fu-Kui Zhang Bao-En Wang liver Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China

AIM： To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of hepatic oval cells in vitro. METHODS： WB-F344 cells were treated with recombinant Wnt3a （20, 40, 80, 160, 200 ng/mL） in serum-free medium for 24 h. Cell proliferation was measured by Brdu incorporation analysis; untreated WB-F344 cells were taken as controls. After treatment with Wnt3a （160 ng/mL） for 24 h, subcellular localization and protein expression of p-catenin in WB-F344 cells treated and untreated with Wnt3a were examined by immunofluorescence staining and Western blot analysis. CyclinD1 mRNA expression was determined by semi-quantitative reverse-transcript polymerase chain reaction （RT-PCR）. The mRNA levels of some phenotypic markers （AFP, CK-19, ALB） and two hepatic nuclear factors （HNF-4, HIVF-6） were measured by RT-PCR. Expressions of CK-19 and AFP protein were detected by Western blot analysis. RESULTS： Wnt3a promoted proliferation of WB-F344 cells. Stimulation of WB-F344 cells with recombinant Wnt3a resulte^l in accumulation of the transcriptional activator β-catenin, together with its translocation into the nuclei, and up-regulated typical Wnt target gene CyclinD1. After 3 d of Wnt3a treatment in the absence of serum, WB-F344 cells retained their bipotential to express several specific phenotypic markers of hepatocytes and cholangiocytes, such as AFP and CK-19, following activation of the canonical Wnt signaling pathway. CONCLUSION： The canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cells.

关键词： Canonical Wnt signaling pathway Oval cells Cell proliferation Self-renewal of cells

The complete mitogenome of Lamproptera curia （Lepidoptera： Papilionidae） and phylogenetic analyses of Lepidoptera

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Frontiers in Biology 2015年第5期10卷 458-472页

作者： xin-min Qin Qing-xin Guan Hui-min li Yu Zhang Yu-Ji liu Dan-Ni Guo Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life Science Guangxi Normal University Guilin 541004China

The complete mitochondrial genome sequence of Lamproptera curia was determined in the present study. Our findings showed that the mtDNA of L. curia had a typical organization of insect mitochrondrial DNA - being 15277 base pairs in length, it contained 13 protein-coding genes （PCGs）, 2 rRNA genes, 22 tRNA genes, and a control region （CR）. The newly determined sequence was used for phylogenetic analyses, together with those of 45 species of Lepidoptera published elsewhere, including sequences of three species of Diptera as outgroups. The phylogenetic trees were constructed using the concatenated amino acid and nucleotide sequences of the 13 protein-coding genes （PCGs） based on the maximum likelihood （ML） and Bayesian inference （BI） methods. Both BI and ML trees revealed a similar topology structure：（（（（（Bombycoidea ＋ Geometroidea）＋ Noctuoide）＋ Pyraloidea）＋（Papilionoidea ＋ Hesperioidea））＋ Tortricoidea）. Furthermore, the phylogenetic analyses demonstrated that each of the 16 families belonged to a monophyletic group respectively. The results of molecular phylogeny from the present study were congruent with traditional classification based on morphology but failed to demonstrate the monophyly of Hesperiidae.

关键词： Lamproptera curia phylogeny mitochondrial genome

Oxygen-promoted Pd/C-catalyzed Suzuki–Miyaura reaction of potassium aryltrifluoroborates

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Chinese Chemical Letters 2016年第5期27卷 631-634页

作者： Chun liu Chao liu xin-min li Zhan-ming Gao Zi-lin Jin State Key Laboratory of Fine Chemicals Dalian University of Technology

A simple and highly efficient protocol has been developed for the Pd/C-catalyzed ligand-free Suzuki- Miyaura reaction of potassium aryltrifluoroborates. In this catalytic system, the results demonstrate that oxygen plays a positive role in the cross-coupling reaction. In addition, this catalytic system could be successfully applied to synthesize biaryl compounds containing a carbazole moiety and the catalyst was recycled seven times without significant loss of catalytic activitv.

关键词： Pd/C Oxygen-promoting effect Suzuki-Miyaura reaction Potassium aryltrifluoroborates Carbazole derivatives

Silence of STIM1 attenua=tes the proliferation and migration of EPCs after vascular injury and its mechanism

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Asian Pacific Journal of Tropical Medicine 2014年第5期7卷 373-377页

作者： xin-Peng Cong Wen-Hui Wang Xi Zhu Can Jin liang liu xin-min li Affiliated Shanghai East Hospital of Tongji University Shanghai Zhoupu Hospital

Objective:To investigate the effect of stromal interaction molecule 1（STIM1） knockdown on the proliferation and migration of endothelial progenitor cells（EPCs） after vascular injury and its ***:The rat bone marrow derived EPCs were divided into three groups:adenovirus negative control（group NSC）,rat STIM1 adenovirus vector transfection group（group si/rSTIM1） and rat &human recombinant STIM1 adenovirus transfection group（group si/rSTlM1+hSTIM1）.The STIM1 expressions in each group were detected by reverse transcription PCR after transfection;the cell proliferation was tested by[3H]thymidine incorporation assay（3HTdR）;Cell cycle was analyzed by flow cytometry;the cells’ migration activity was detected by Boyden assay;Calcium ion concentration was detected by using laser confocal ***:48 h later after transfection,the expression level of STIM1 in si/rSTIM1 cells was significantly lower than that in NSC group（0.21±0.12 vs 1.01±0.01,P1 phase in si/rSTIM1 group[（93.3l±0.24）%]were significantly more than that in NSC group[（78.03±0.34）%,Pliferation and migration after vascular injury,by mediating the calcium ion concentration in EPCs.

关键词： Vascular injury STIM1 Proliferation Migration tEPCs

Complex Boronized Layer on the Hot-dip Aluminized Steels and Its Surface Performances

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材料热处理学报 2004年第05B期25卷 653-656页

作者： LUOxin-min liDian-kai WANGLan CHENKang-min JiangsuUniversity ZhenjiangJiangsuP.R.China

Plain carbon steels were dipped in molten aluminum bath at 720°C ±5°C and diffused for 1, 2.5 and 6 hours respectively and then boronized at 950°C for 6 hours. The oxidation, hot-corrosion and abrasion resistance behavior were examined. The experimental results showed the compounds of the aluminized layer, from the surface to the matrix, were composed of Fe2Al5 ( n -phase ) .. Fe3Al ( -phase ) and a phase. The microstructure of aluminized plus complex boronized were similar to that simplex boronized. The XRD analysis results indicated that there existed Fe2B> Fe2AlB2and Fe2Als in this kind of layer. The simplex aluminized layers still remained bright gray appearance when oxidized at 950°C, but complex boronized layer was not able to resist oxidization at the temperature. Both the layers of complex boronized and aluminized had the same anti-oxidization level in the circulative oxidization tests, and also good anti-corrosion ability in molten salt medium. Under dry abrasive conditions, wear resistance of complex boronized layer was superior to the aluminized layer.

关键词：热镀喷铝钢硼化热腐蚀磨损

Application of ozonated water for treatment of gastro-thoracic fistula after comprehensive esophageal squamous cell carcinoma therapy: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4550-4557页

作者： De-Di Wu Ke-Nan Hao Xiao-Jing Chen xin-min li Xiao-Feng He Division of Vascular and Interventional Radiology Department of General SurgeryNanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

BACKGROUND Gastro-thoracic fistula is a serious complication after radical surgery for esophageal cancer,and a conservative approach or endoscopic intervention is commonly applied to treat most *** SUMMARY Here we describe the case of a patient with a gastro-thoracic fistula which could not be closed during gastroscopy after receiving postoperative radiotherapy,together with severe multiple drug-resistant bacterial infection and chest wall *** abscess was drained and local irrigation applied with ozonated water,together with oral ozonated water,which achieved a good effect and highlighted a new way to cure fistula in such *** Patients with gastro-thoracic fistula that cannot be closed and severe infection can be treated by drainage and flushing with ozonated water.

关键词： Esophageal squamous cell carcinoma Ozonated water Radiotherapy Gastrothoracic fistula Drug-resistant bacterial infection Case report

Subconjunctival trypsin injection for anterior chamber fibrin exudates in eyes with globe rupture following vitrectomy

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International Journal of Ophthalmology(English edition) 2024年第11期17卷 2037-2044页

作者： Shu-Wen Lu Hao-Yu li xin-min li Chao Ma Xian li Qiu-ming Hu Department of Ophthalmology the First Affiliated Hospital of Henan University of Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Ophthalmology the Second Xiangya HospitalCentral South UniversityChangsha 410021Hunan ProvinceChina Hunan Clinical Research Centre of Ophthalmic Disease Changsha 410021Hunan ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Xinxiang Medical UniversityXinxiang 453100Henan ProvinceChina Department of Ophthalmology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina School of Pharmacy and Optometry Faculty of BiologyMedicine and HealthThe University of ManchesterManchester M139PLUnited Kingdom Department of Retina and Vitreous Jingliang Eye HospitalGuangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repair and ***:A retrospective analysis included 42 males and 10 females(mean age 46.0±6.0y,range 34 to 58y)who underwent primary wound sutures and vitrectomy for globe *** with pupil-covered fibrinous exudate or/and membrane in the anterior chamber were *** the first postoperative day,subconjunctival injections of either 5000 units(0.4 mL)of trypsin solution(n=25)or 0.5 mL(1 mg)DEX(n=27)were administered to accelerate exudate *** was assessed by observing break time and partial absorption of the fibrin exudate *** and comfort were evaluated by monitoring intraocular pressure(IOP),allergy,pain,and foreign body ***:Both groups achieved 1/3 absorption of the anterior chamber fibrin exudate membrane,but the trypsin group exhibited shorter break time and partial absorption time compared to the DEX group(P<0.05).Trypsin treatment was also less irritating to *** adverse reactions were reported,and IOP remained *** acuity improved in both groups without statistical ***:Compared to DEX,trypsin demonstrates a shorter absorption time for the fibrin exudate membrane with a more comfortable process in treating pupil-covered fibrinous exudate or/and membrane after vitrectomy for globe rupture.

关键词： globe rupture vitrectomy exudative fibrin membrane trypsin dexamethasone