检索结果-南通市图书馆

Nanocellulose: Effect on Thermal, Structural, Molecular Mobility and Rheological Characteristics of Poly(Butylenes Adipate-Co-Butylene Terephthalate) Nanocomposites

引用

Materials Sciences and Applications 2022年第4期13卷 249-277页

作者： Gerson Alberto Valencia Albitres francisco pereira araujo junior Daniela França Silva Freitas Danielle Mattos Mariano Maria Ines Bruno Tavares Luis Claudio Mendes Universidade Federal do Rio de Janeiro Instituto de Macromoléculas Professora Eloisa Mano Rio de Janeiro Brazil

The concern with environmental preservation is a very current and relevant topic. Regarding polymers, the search for potentially ecofriendly matters has been the subject of scientific research. In this context, this work aimed to study the effect of adding nanocellulose (nCE) with 1, 3, and 5 wt.% on poly(butylene adipate-co-butylene terephthalate) (PBAT). Thermal, structural, relaxometric, and rheological assessments were carried out. Quantitative evaluation of PBAT copolymer by high field NMR revealed 56.4 and 43.6 m.% of the butylene adipate and butylene terephthalate segments, respectively. WAXD measurement on the deconvoluted diffraction patterns identified that nCE was a mixing of Cellulose I and Cellulose II polymorph structures. At any composition, nanocellulose interfered with the PBAT crystallisation process. Also, a series of new PBAT crystallographic planes appeared as a function of nanocellulose content. PBAT hydrogen molecular relaxation varied randomly with nanocellulose content and had a strong effect on the hydrogen relaxation. PBAT cold crystallisation and melting temperatures (Tcc and Tm) were almost unchangeable. Although Tcc did not change during polymer solidification from PBAT molten state, the sample’s degree of crystallinity varied with composition through the transcrystallization phenomenon. Nanocomposite thermal stability decreased possibly owing to the catalytic action of sulfonated amorphous cellulose chains. For the sample with 3 wt.% of nanocellulose, the highest values of complex viscosity and storage modulus were achieved.

关键词： Nanocellulose Poly(Butylene Adipate-Co-Butylene Terephthalate) Molecular Relaxation Nanocomposite

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Recovery of polyphenols from camu-camu(Myrciaria dubia ***)depulping residue by cloud point extraction

引用

Chinese Journal of Chemical Engineering 2018年第12期26卷 2471-2476页

作者： Carlos Eduardo de araujo Padilha Juliana Chris Silva de Azevedo francisco Caninde de Sousa junior Sergio Dantas de Oliveira junior Domingos Fabiano de Santana Souza Jackson araujo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos Laboratory of Biochemical Engineering Chemical Engineering Department Federal University of Rio Grande do Notre(UFRN)NatalRNBrazil Laboratory of Food Bioactive Compounds and Dairy Technology Chemical Engineering DepartmentFederal University of Rio Grande do Notre(UFRN)NatalRNBrazil

In this study the potential of cloud point extraction formed by a non-ionic surfactant was used in order to separate polyphenols from industrial residues of camu-camu. The effects of operational conditions of the cloud point extraction(CPE) on the polyphenol recovery and volumetric ratio were investigated. The results showed a maximum recovery of 95.71% that was obtained using 7.0 wt% Triton X-114, native pH(3.25), and 80 wt%polyphenol extract at 30 °C. The use of cloud point extraction was successful to recover the polyphenols from agroindustrial residue since it is a simple as well as of low-cost technique.

关键词： Cloud point extraction Recovery Polyphenols Camu-camu Depulping residue

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microbial enzymatic stoichiometry and the acquisition of C, N,and P in soils under different land-use types in Braziliansemiarid

引用

Soil Ecology Letters 2023年第3期5卷 101-108页

作者： Erika Valente de Medeiros Érica de Oliveira Silva Gustavo pereira Duda Mario Andrade Lira junior Uemeson Josédos Santos Claude Hammecker Diogo Paes da Costa Fabio Fernando araujo Arthur Prudêncio de araujo pereira Lucas William Mendes Ademir Sergio Ferreira araujo Laboratory of Microbiology and Enzymology-LEMA Federal University of Agreste PernambucoGaranhuns 55292-270Brazil Federal Rural University of Pernambuco Rua Dom Manuel de Medeiross/nDois Irmãos52171-900RecifeBrazil Soil-Agrosystem-Hydrosystem Interaction Lab-LISAH Place Pierre Viala234060 MontpellierFrance Universidade do Oeste Paulista Presidente PrudenteSPBrazil Departamento de Ciência Do Solo Universidade Federal Do CearáFortalezaCEBrazil Center for Nuclear Energy in Agriculture University of Sao PauloPiracicabaSPBrazil Soil Quality Lab Agricultural Science CenterFederal University of PiauíTeresinaPI 60049-550Brazil

This study hypothesized that different land-use affect the microbial enzymatic stoichiometry and C-,N-,and P-acquisition in Brazilian semiarid ***,the enzymesβ-glucosidase(C-acquiring enzyme),urease(N-acquiring enzyme),and acid phosphatase(P-acquiring enzyme)were assessed in soil samples collected at 0−5 and 5−10 cm depth from a tropical dry forest,a protected area with Angico,a protected area with Ipê,scrub area,and an agricultural area with *** values of C-,N-,and P-acquiring enzymes were used to calculate the enzymatic C:N,C:P,and N:P *** values of C:P and N:P ratios were higher at 0−5 cm depth,while no significant variation,between soil depth,was observed for C:N *** values of C-and N-acquiring enzymes were higher at 0−5 cm in tropical dry forest areas and Angico forest,*** all land use types,the values of vectors L and A were higher than 1°and 45°,*** study showed that both land-use and soil depth influence the enzymatic stoichiometry,showing higher values of C-and N-acquiring enzymes in native and protected forests at soil surface.

关键词： C:N:P stoichiometry tropical forests soil depth Luvisols

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Corneal stem cells and tissue engineering: Current advances and future perspectives

引用

World Journal of Stem Cells 2015年第5期7卷 806-814页

作者： Aline Lütz de araujo JoséAlvaro pereira Gomes Clínica Lentecor Porto Alegre-RS 90570041Brazil Department of Ophthalmology and Visual Sciences Universidade Federal de São PauloSao Paulo-SP 04023062Brazil

Major advances are currently being made in regenerative medicine for cornea. Stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there aremany challenges ahead given the singularities of each cellular layer of the cornea. This review recapitulates the current data on corneal epithelial stem cells, corneal stromal stem cells and corneal endothelial cell progenitors. Corneal limbal autografts containing epithelial stem cells have been transplanted in humans for more than 20 years with great successful rates, and researchers now focus on ex vivo cultures and other cell lineages to transplant to the ocular surface. A small population of cells in the corneal endothelium was recently reported to have self-renewal capacity, although they do not proliferate in vivo. Two main obstacles have hindered endothelial cell transplantation to date: culture protocols and cell delivery methods to the posterior cornea in vivo. Human corneal stromal stem cells have been identified shortly after the recognition of precursors of endothelial cells. Stromal stem cells may have the potential to provide a direct cell-based therapeutic approach when injected to corneal scars. Furthermore, they exhibit the ability to deposit organized connective tissue in vitro and may be useful in corneal stroma engineering in the future. Recent advances and future perspectives in the field are discussed.

关键词： Cornea Stem cells Cell-based therapy Limbal transplantation Tissue engineering Cornealendothelium

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Updatism:Pandemic and Historicities in the Never-Ending 2020

引用

Journal of Foreign Languages and Cultures 2021年第2期5卷 90-102,155,156页

作者： Mateus Henrique de Faria pereira Valdei Lopes de araujo Federal University of Ouro Preto

In this essay we demonstrate that the present and the future are also history and must be dimensions of *** that,we return to episodes from our book Alamanac of COVID-19 and some of our readings of key moments of this year in order to reflect on what we have called updatist *** some moments we use the retrospective as a *** others we choose to maintain the anachronistic effect of certain passages in order to highlight the contingent aspect of all representation of *** divided the text into three main *** first presents the most recent shifts in the hypothesis about an updatist *** the second,we gathered some episodes from 2020 as a way to elucidate what we are calling updatism in its relations with politics and history,and finally we point out preliminary paths for action with counter-updatist effects.

关键词： updatism COVID-19 historicity politics time

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Characterization of Cnidoscolus quercifolius Pohl bark root extract and evaluation of cytotoxic effect on human tumor cell lines

引用

Asian Pacific Journal of Tropical Biomedicine 2018年第7期8卷 345-351页

作者： Paulo Fernando Machado Paredes Selene Maia de Morais Fernando Cesar Rodrigues Brito Luiz francisco Wemmenson Goncalves Moura Patricia de araujo Rodrigues Stephen Rathinaraj Benjamin francisco Ernani Alves Magalhaes Eridan Orlando pereira Tramontina Florean Maria Izabel Florindo Guedes Northeast Biotechnology Network Graduate Program of Biotechnology State University of Ceara Itaperi campus Department of Chemistry State University of Ceara Itaperi campus Laboratory of Bioprospecting of Natural Products and Biotechnology State University of CearaCECITEC

Objective: To evaluate the chemical components of active extract from Cnidoscolus quercifolius root bark and its cytotoxic potential against several tumor strains. Methods: The high-performance liquid chromatography with diode-array detection and ~1H and ^(13)C nuclear magnetic resonance spectroscopy of the extract were used to distinguish the existence of possible functional groups in the root bark extract. The in vitro cytotoxic activity of methanol extract on human colon cancer cell lines was evaluated using OVCAR-8, SF-295, HCT-116, HL-60 strains and the samples were assessed by 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyltetrazolium bromide method. Results: The analysis of nuclear magnetic spectra of the active chloroform fraction revealed the presence of absorptions bands correspondent to a mixture of favelines such as neofavelanone, deoxofaveline or methyl-faveline, which structures were confirmed by ultraviolet spectra upon high-performance liquid chromatography with diode-array detection analysis. The active fraction showed cytotoxic effects in the tested strains, HCT-116, SF-295, OVCAR-8 and HL-60 cells with IC_(50) of 72 hours ranging from 4.95 to 15.23 μg/mL. Conclusions: The results suggest that the substances present in faveleira(Cnidoscolus quercifolius) root bark extract have a cytotoxic potential against several tumor lines, showing a broader antitumour potential, and in addition no adverse to healthy cells. Therefore, the root bark extract of Cnidoscolus quercifolius has a possibility of use for anticarcinogenic therapies.

关键词： Cnidoscolus quercifolius Pohl. methyl-faveline Deoxofaveline Neofavelanone Faveline Cytotoxicity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

19-year remotely sensed data in the forecast of spectral models of the environment

引用

International Journal of Digital Earth 2021年第8期14卷 1040-1066页

作者： Fernando Saragosa Rossi Carlos Antonio da Silva junior Joséfrancisco de Oliveira-Júnior Paulo Eduardo Teodoro Luciano Shozo Shiratsuchi Mendelson Lima Larissa pereira Ribeiro Teodoro Auana Vicente Tiago Guilherme Fernando Capristo-Silva State University of Mato Grosso(UNEMAT) Alta FlorestaMato GrossoBrazil Department of Geography State University of Mato Grosso(UNEMAT)SinopMato GrossoBrazil cFederal University of Alagoas(UFAL) MaceióAlagoasBrazil dFederal University of Mato Grosso do Sul(UFMS) Chapadão do SulMato Grosso do SulBrazil eAgCenter School of PlantEnvironmentaland Soil SciencesLouisiana State University(LSU)Baton RougeLouisianaUSA fPostgraduate Program in Agronomy Federal University of Mato Grosso(UFMT)SinopMato GrossoBrazil

The aims of this study were:i)to compare no-till areas in two municipalities located in different regions of Brazil,along with the influence on CO_(2)Flux and GPP,and ii)to verify the difference between environmental factors followed by the trends of these variables regarding future scenarios(ARIMA time-series model number).The study was carried out in two areas with different latitudes in the municipalities of Sinop-MT and Passo Fundo-RS,both in Brazil.A time series of 19 years was performed with data acquired by remote sensing from the following satellites:i)Landsat-8(OLI and TIRS),and ii)TERRA/AQUA(MODIS).The results propound that the spectro-temporal variables are directly influenced by soil management and agricultural practices over the observation time,with a satisfactory correlation in future predictions of the variables for the next ten years,in which presented that the variation of GPP and albedo values for the two study sites would gradually increase until 2028 and the temperature remained constant between the range of its seasonality,and CO_(2)Flux tends to decrease in its seasonality,indicating a higher CO_(2) absorption.

关键词： ARIMA numerical modeling remote sensing orbital products tillage

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Eucalyptol prevents pilocarpine-induced seizure and neuronal damage in mice,through the cholinergic,monoaminergic and antioxidant pathways

引用

Food Bioscience 2023年第3期53卷 3059-3066页

作者： Daniel Souza Bezerra Gyllyandeson de araujo Delmondes Maria Janice pereira Lopes Isaac Moura araujo Giovana Mendes de Lacerda Leite Maysa de Oliveira Barbosa Roseli Barbosa Adriano francisco Alves Cassio Rocha Medeiros Sloana Giesta Lemos Florencio Irwin Rose Alencar de Menezes Henrique Douglas Melo Coutinho Cicero francisco Bezerra Felipe Marta Regina Kerntopf Regional University of Cariri(URCA) Department of Biological Chemistry(DBQ)PimentaCrato63105-000Ceará-CEBrazil Federal University of Paraíba(UFPB) Departamento de Biologia Molecular(DBM)Cidade Universitária58051-900João PessoaPBBrazil CECAPE College Av.Padre Cícero3917São JoséJuazeiro do NorteCE63024-015Brazil

Current antiepileptic drugs can inhibit seizure occurrence but are not effective in preventing its ***,they produce several side effects,which may impact the efficacy of the *** addition,it has been stimulating the prospection of new molecules isolated from aromatic plants,with potential anticonvulsant and neuroprotective activities and less side *** study aimed to evaluate,though behavioural and neuro-chemical methodologies,the anticonvulsant,and neuroprotective effects of eucalyptol on mice subjected to the pilocarpine-induced seizure ***(100,200 and 400 mg/kg,p.o.)was administered in mice prior to pilocarpine(350 mg/kg,i.p.)and the following behavioural parameters were assessed:Latency to First Seizure(LFS),Seizure Intensity(SI)and Latency to Death(LD).In addition,an oxotremorine-induced tremors test was performed to evaluate the cholinergic system involvement on the eucalyptol *** tests were also performed,including determination of hippocampal(HC)concentration of thiobarbituric acid reactive substances(TBARS)and nitrite/nitrate and striatal(ST)concentration of noradrenaline,dopamine,and ***,histopathological,and morphometric hippocampal analysis were *** increased the latency to first seizure and latency to death,inhibited oxotremorine-induced tremors,decreased hippocampal TBARS and nitrite/nitrate overproduction,increased striatal noradrenaline and dopamine levels and prevented hippocampal *** results demonstrate the potential anticonvulsant,neuroprotective and antioxidant effects of eucalyptol,probably through a conjunction of mechanisms including muscarinic cholin-ergic antagonism,oxidative stress mitigation and the monoaminergic system modulation,which appears to effectively control the seizure onset.

关键词： Seizure Pilocarpine Eucalyptol Monoamines Antioxidant Neuroprotection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanisms of neuroplasticity and brain degeneration: strategies for protection during the aging process

引用

Neural Regeneration Research 2021年第1期16卷 58-67页

作者： Mariana Toricelli Arthur Antonio Ruiz pereira Guilherme Souza Abrao Helena Nascimento Malerba Julia Maia Hudson Sousa Buck Tania araujo Viel Department of Physiological Sciences Santa Casa de Sao Paulo School of Medical SciencesSao PauloBrazil Laboratory of Neurobiology of Aging School of ArtsSciences and HumanitiesUniversidade de São PauloSao PauloBrazil

Aging is a dynamic and progressive process that begins at conception and continues until *** process leads to a decrease in homeostasis and morphological,biochemical and psychological changes,increasing the individual’s vulnerability to various *** growth in the number of aging populations has increased the prevalence of chronic degenerative diseases,impairment of the central nervous system and dementias,such as Alzheimer’s disease,whose main risk factor is age,leading to an increase of the number of individuals who need daily support for life *** theories about aging suggest it is caused by an increase of cellular senescence and reactive oxygen species,which leads to inflammation,oxidation,cell membrane damage and consequently neuronal ***,mitochondrial mutations,which are generated throughout the aging process,can lead to changes in energy production,deficiencies in electron transport and apoptosis induction that can result in decreased ***,increasing cellular senescence and the release of proinflammatory cytokines can cause irreversible damage to neuronal *** reports point to the importance of changing lifestyle by increasing physical exercise,improving nutrition and environmental enrichment to activate neuroprotective defense ***,this review aims to address the latest information about the different mechanisms related to neuroplasticity and neuronal death and to provide strategies that can improve neuroprotection and decrease the neurodegeneration caused by aging and environmental stressors.

关键词： cell senescence cell signaling cholinergic enriched environment long-term potentiation neurodegeneration neurogenesis neuroinflammatory neuronal death neuroprotection neurotophin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prognosis value of heat-shock proteins in esophageal and esophagogastric cancer:A systematic review and meta-analysis

引用

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1578-1595页

作者： Eric Toshiyuki Nakamura Amanda Park Marina Alessandra pereira Daniel Kikawa francisco Tustumi Department of Gastroenterology Instituto do CâncerHospital das Clínicas da Universidade de São PauloFaculdade de MedicinaUniversidade de São PauloSão Paulo 01246000Brazil Department of Scientific Initiation Universidade Mogi das CruzesSão Paulo 08780911Brazil Department of Evidence-Based Medicine Centro Universitário LusíadaCentre for Evidence-Based MedicineCentro Universitário Lusíada(UNILUS)SantosBrazil Department of Surgery Hospital Israelita Albert EinsteinSão Paulo 05652900Brazil

BACKGROUND Heat shock proteins(HSPs)are molecular chaperones that play an important role in cellular protection against stress events and have been reported to be overex-pressed in many *** prognostic significance of HSPs and their regulatory factors,such as heat shock factor 1(HSF1)and CHIP,are poorly *** To investigate the relationship between HSP expression and prognosis in esophageal and esophagogastric *** A systematic review was conducted in accordance with PRISMA recommend-ations(PROSPERO:CRD42022370653),on Embase,PubMed,Cochrane,and ***,case-control,and cross-sectional studies of patients with eso-phagus or esophagogastric cancer were ***-positive patients were compared with HSP-negative,and the endpoints analyzed were lymph node metastasis,tumor depth,distant metastasis,and overall survival(OS).HSPs were stratified according to the HSP family,and the summary risk difference(RD)was calculated using a random-effect *** The final selection comprised 27 studies,including esophageal squamous cell carcinoma(21),esophagogastric adenocarcinoma(5),and mixed neoplasms(1).The pooled sample size was 3465 ***40 and 60 were associated with a higher 3-year OS[HSP40:RD=0.22;95%confidence interval(CI):0.09-0.35;HSP60:RD=0.33;95%CI:0.17-0.50],while HSF1 was associated with a poor 3-year OS(RD=-0.22;95%CI:-0.32 to-0.12).The other HSP families were not associated with long-term ***1 was associated with a higher probability of lymph node metastasis(RD=-0.16;95%CI:-0.29 to-0.04).HSP40 was associated with a lower probability of lymph node dissemination(RD=0.18;95%CI:0.03-0.33).The expression of other HSP families was not significantly related to tumor depth and lymph node or distant *** The expression levels of certain families of HSP,such as HSP40 and 60 and HSF1,are associated with long-term survival and lymph node dissemination in patients with esophageal and esophagogastric cancer.

关键词： Heat-shock proteins Heat-shock response Prognosis Esophageal neoplasms Meta-analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：