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Open Journal of Ecology 2016年第1期6卷 13-21页

作者： Francisco Anguebes-Franseschi Atl Córdova-Quiroz Julia Cerón-Bretón Claudia Aguilar-Ucan Gloria Castillo-martínez Rosa Cerón-Bretón alejandro ruíz-marín Carlos Montalvo-Romero Facultad de Química Universidad Autónoma del Carmen Ciudad del Carmen México Departamento de Informática Instituto Tecnológico de Villahermosa Villahermosa México

In this study, African crude palm olein (CPO) was used to synthesize biodiesel. The objective was to determine the optimal reaction conditions for the methanolysis of olein. The used CPO had a 5.72% concentration of free fatty acids (FFA);thus, the production of biodiesel was carried out in two stages: 1) esterification using sulfuric acid and 2) transesterification using sodium methoxide. In order to optimize the yield of biodiesel during the transesterification process, a central rotatable design and the response surface methodology were used. The studied variables were: catalyst loading, reaction time and reaction temperature. The analysis of variance showed that the variables with significant effect were the catalyst loading, reaction temperature and reaction time;as well as the catalyst loading*reaction temperature and catalyst loading*reaction time. Results indicate that the optimal reaction conditions during transesterification are: 0.65% catalyst loading (wt/wtaceite), reaction time of 135 min and a reaction temperature of 56°C. The optimal reaction conditions during esterification are: 2.5% weight of catalyst, reaction time of 150 min and a reaction temperature of 64.5°C. Under these conditions, a 90% yield of biodiesel was obtained.

关键词： Acid Catalysis Alkaline Catalysis Biodiesel Process Optimization Response Surface Methodology

Acquired sensorineural hearing loss,oxidative stress,and microRnAs

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neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.nunez ru C.Guo Division of Otolaryngology–Head&neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British Columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RnA sequences known as microRnAs(miRnAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLInE,Web of Science Core Collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRnAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRnAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P GC-1α),SIRT

关键词： hearing loss hypoxia microRnAs oxidative stress sensorineural

Carbon Dioxide/Methane Separation by Adsorption on Sepiolite

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Journal of natural Gas Chemistry 2007年第3期16卷 235-243页

作者： José A.Delgado maría A.Uguina José L.Sotelo Beatriz ruíz marcio Rosário Department of Chemical Engineering Universidad Complutense de Madrid28040Madrid.Spain

In this work, the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption （PSA） process has been researched. Adsorption equilibrium and kinetics have been measured in a fixed-bed, and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained. A model based on the LDF approximation has been employed to simulate the fixed-bed kinetics, using the Langmuir equation to describe the adsorption equilibrium isotherm. The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied. The experimental results were compared with the ones predicted by the model adapted to a PSA system. Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle. These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases.

关键词： carbon dioxide methane sepiolite adsorption fixed-bed pressure swing adsorption

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu na Li zhengxiang zhou ru Ye Liyan zhong Yashuang Xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du Department of neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

miRnA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie zhu Xiao-Jia Yang Qian-ru He Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRnA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RnA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRnA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

Conversion of Andean montane forest to exotic forest plantation modifies soil physicochemical properties in the buffer zone of Ecuador's Podocarpus national Park

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Forest Ecosystems 2022年第6期9卷 802-812页

作者： Vinicio Carrion-Paladines Angel Benítez Roberto García-ruíz Departamento de Ciencias Biologicas y Agropecuarias Universidad Tecnica Particular de LojaSan Cayetano Alto s/nC.P.1101608LojaEcuador Departamento de Biología Animal Biología Vegetal y EcologíaSeccion de EcologíaUniversidad de JaenCampus Las LagunillasEdificio Ciencias Experimentales y de la Salud(B3)23071JaenSpain

Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and *** recent decades,southern Ecuador AMFs have been seriously threatened by increased logging and conversion to forest plantations with exotic *** this context,our main objective was to evaluate the effects of AMF conversion to forest plantations on soil physicochemical properties in the buffer zone(Bz)of the Podocarpus national Park(PnP),in southern *** this purpose,random samples were taken at a depth of 0-10 cm in four plots in each contrast zone and analyzed for bulk density,porosity,textural class,leaf litter depth,soil pH,as well as the contents of organic matter(SOM),soil organic carbon(SOC),total nitrogen,and available phosphorus and ***:The results indicate that the conversion of AMFs produces an increase in bulk density and a decrease in SOM,SOC,and total nitrogen contents,thus modifying soil properties,which could result in a decrease in water regulation capacity and produce an increased risk of soil *** accelerates degradation processes,as well as threatens shortages of the drinking water ***:This study can help decision-makers to implement soil management plans in the Bz of the PnP,based on the implementation of new regulations,where the conservation of AMF is *** addition,it is recommended to apply environmental restoration strategies in the anthropized areas of the AMF,as well as in the areas with exotic eucalyptus and pine plantations.

关键词： Andean montane forests Land use conversion Edaphic properties

Detection of KRAS G12D in colorectal cancer stool by droplet digital PCR

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World Journal of Gastroenterology 2017年第39期23卷 7087-7097页

作者： Susana Olmedillas-López Dennis César Lévano-Linares Carmen Laura Aúz Alexandre Luz Vega-Clemente Edurne León Sánchez alejandro Villagrasa Jaime ruíz-Tovar mariano García-Arranz Damián García-Olmo Foundation Health Research Institute-Fundación Jiménez Díaz University Hospital Department of Surgery School of Medicine Universidad Autónoma de Madrid Department of Surgery Rey Juan Carlos University Hospital Department of Pathology Fundación Jiménez Díaz University Hospital Department of Biomedicine and Biotechnology Universidad de Alcalá Department of Surgery Fundación Jiménez Díaz University Hospital

AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DnA from colorectal cancer (CRC) *** this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DnA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DnA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DnA by ddPCR was performed for these patients as *** the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DnA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DnA in 80% of all fecal samples from CRC patients with this point *** is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DnA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management.

关键词： Droplet digital PCR KRAS Stool Formalin-fixed paraffin-embedded Pyrosequencing Colorectal cancer

An improvement of Chen-ru-Yan's degenerated second main theorem

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Science China Mathematics 2015年第12期58卷 2517-2530页

作者： SHI Lei ru Min Department of Mathematics East China Normal University Department of Mathematics University of Houston

We give an improvement for the second main theorem of algebraically non-degenerate holomorphic curves into a complex projective variety V intersecting hypersurfaces in subgeneral position, obtained by Chen et al.(2012... 详细信息

关键词： nevanlinna theory holomorphic curve second main theorem truncation level

Hepatitis C virus nS5A region mutation in chronic hepatitis C genotype 1 patients who are non-responders to two or more treatments and its relationship with response to a new treatment

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World Journal of Gastroenterology 2017年第25期23卷 4538-4547页

作者： Paloma Munoz de rueda José Manuel Fuentes RodríguezRosa Quiles Pérez Ana Gila Medina Ana Belén martínálvarez Jorge Casado ruíz ángeles ruíz Extremera Javier Salmerón Research Support Unit San Cecilio University Hospital of Granada Instituto de Investigación Biosanitaria CIBERehd Instituto de Salud Carlos III Unit for Clinical Management of Digestive Diseases San Cecilio University Hospital of Granada Granada University

To determine the number of mutations in the nS5A region of the hepatitis C virus (HCV) and its relationship to the response to antiviral therapy in patients with chronic hepatitis C genotype 1 who are non-responders to two or more treatments. METHODSSequences within HCV nS5A [PKR binding domain (PKRBD) and the interferon-sensitivity-determining region (ISDR)] were analysed via direct sequencing in a selected cohort of 72 patients, with a total of 201 treatments [interferon-alpha (IFn-α), n = 49; IFn-α + ribavirin (RBV), n = 75; pegylated (peg) IFn-α + RBV, n = 47; first-generation direct-acting antivirals (DAAs), n = 13; and second-generation DAAs, n = 17]. Of these, 48/201 achieved a sustained virological response (SVR) and 153/201 achieved no virological response (nVR). RESULTSFor both regions, treatments resulting in SVR were associated with more baseline mutations than were treatments resulting in nVR (SVR vs nVR; PKRBD: 5.82 ± 3 vs 4.86 ± 2 mutations, P = 0.045; ISDR: 2.65 ± 2 vs 1.51 ± 1.7 mutations, P = 0.005). A decrease or no change in the number of mutations over time between treatments in the PKRBD or ISDR, as shown by sequencing, was associated with patients who usually failed to respond to treatment (PKRBD, P = 0.02; ISDR, P = 0.001). Moreover, patients showing a post-treatment baseline viral load > 600000 IU/mL and increased ISDR mutations with respect to the previous treatment were 9.21 times more likely to achieve SVR (P = 0.001). COnCLUSIOnThe obtained results show that among patients who have shown no response to two or more antiviral treatments, the likelihood of achieving SVR increases with the genetic variability in the ISDR region (≥ 2 mutations or number of substitutions from the HCV-J and HCV-1 prototype), especially when the viral load is greater than 600000 IU/mL.

关键词： Interferon-based therapy Interferon-free therapy Chronic hepatitis C nS5A region Sustained virological response number of mutations

Endophytic Occupation in nodules of Rhynchosia Plants from Semiarid Regions of Argentina

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1081-1099页

作者： Cinthia T.Lucero maría de los Á.ruíz Fabiola Pagliero Carolina Castaño mariela L.Ambrosino Graciela S.Lorda Facultad de Ciencias Exactas y naturales Universidad Nacional de La PampaRuta Nacional 35km 330Santa RosaLa PampaCP6300Argentina InTA EEA Anguil“Ing.Agr.Guillermo Covas”ruta nacional 5 km 580AnguilLa PampaCC116326Argentina

Beneﬁcial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease *** addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth ***,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid *** vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume *** contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human *** this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were *** isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)*** the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM naCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using *** results showed great variability among the isolates in terms of the characteristics *** legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR *** conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment.

关键词： native strains endophytes PGPR native legumes stress