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An Invasive Succulent Plant (Kalanchoe daigremontiana) Influences Soil carbon and Nitrogen Mineralization in a Neotropical Semiarid Zone

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Pedosphere 2018年第4期28卷 632-643页

作者： Ileana HErrErA Jose r. FErrEr-PArIS Diana BENZO Saul FLOrES Belkis garcia Jafet M. NASSAr Ecuela de ciencias Ambientales Universidad Espiritu Santo Guayaquil 091650 (Ecuador) centro de Ecologla Instituto Venezolano de Investigaciones Cientificas (IVIC) Caracas 1020 (Venezuela) centro de Estudios Botdnieos y Agroforestales Instituto Venezolano de Investigaeiones Cientificas Maracaibo 4005 (Venezuela)

It has long been recognized that plant invasions may alter carbon （c） and nitrogen （N） cycles, but the direction and magnitude of such alterations have been rarely quantified. In this study, we quantified the effects caused by the invasion of a noxious exotic plant, Kalanchoe daigrernontiana （crassulaceae）, on c and N mineralization and enzymatic and microbial activities in the soil of a semiarid locality in Venezuela. We compared soil parameters associated with these processes （c and N mineralization time and the cumulative values, fluorescein diacetate hydrolytic activity, and activities of dehydrogenase, β-glucosidase, glucosaminidase, and urease） between invaded and adjacent non-invaded sites. In addition, correlations among these parameters and the soil physical-chemical properties were also examined to determine if a positive feedback exists between nutrient availability and K. daigremontiana invasion. Overall, our results showed that c mineralization and transformation of organic compounds to NH4^＋ were favored at sites colonized by K. daigrernontiana. With this species, we found the highest cumulative amounts of NH4^＋-N and c and the lowest mineralization time. These results could be explained by higher activities of urease and glueosaminidase in soils under the influence of K. daigremontiana. In addition, higher amounts of organic matter and moisture content in invaded soils might favor c and N mineralization. In conclusion, invasion of Neotropical semiarid zones by K. daigrernontiana may influence the chemical and biological properties of the soils covered by this species, increasing nutrient bioavailability, which, in time, can facilitate the invasion process.

关键词： Akaike Information criterion c and N pools enzymatic activity NH4^+-N NO3^--N nutrient availability plant invasion

Microwave-ultrasound assisted extraction of red corn pigments and their effect on chemical composition and tecno-functional properties

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Food Bioscience 2022年第6期50卷 1111-1119页

作者： J.D.garcia-Ortiz A.c.Flores-gallegos J.A.Ascacio-Valdés c.M.López-Badillo S.D.Nery-Flores S.c.Esparza-gonzález r.rodríguez-Herrera School of chemistry Autonomous University of CoahuilaCampus SaltilloSaltilloCoahuila25280Mexico School of Dentistry Autonomous University of CoahuilaCampus SaltilloSaltilloCoahuila25125Mexico

currently, there is a growing interest in obtaining natural pigments, without presenting a risk to health, as well as to the matrix and food safety. The objective of this study was to characterize grains with different shades of red color (High pigmentation maize = rA, Medium pigmentation maize = rM, and Low pigmentation maize = rB, reddish maize with white segments = VO and white maize control = Sc). The physical properties (kernel weight, length, width, thickness, and grain and flour color), chemical composition (moisture, fat, protein, fiber, starch, ash, and minerals), and techno-functional properties (capacity of absorption of organic molecules (OMAc), swelling (cH), oil retention (cAAc), and water absorption (WAS)) variables were measured. Afterward, rM was selected, and a pigment extraction (EAUM) was carried out using microwave-ultrasound equipment with different ratios of ethanol (0, 30, and 70%) and citric acid ratios (0 and 1%). The color and properties of the solid (starch, protein, fat, and their techno-functional properties) were determined in the aqueous phase and were compared with the properties prior to EAUM. The results indicated that the red grains have higher starch content (57.6%) and reddish colors, in addition, VO presented higher moisture (10.4%), fat (6.7%) and fiber (10.0%). The colors of the pigments obtained with EtOH (30 and 70%) show shades red and yellow. Finally, the EAUM decreased the fat content up to 57%, increased WAS and cAAc in the residual flour and generated changes in OMAc and cH, increasing in aqueous medium and reducing with EtOH.

关键词： Natural colorant Zea mays green extraction Proximal analysis NIr Agronomic properties

Plasmonic metasurface Luneburg lens

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Photonics research 2019年第10期7卷 1112-1118页

作者： c.E.garcia-OrTIZ r.cOrTES J.E.gOMEZ-cOrrEA E.PISANO J.FIUTOWSKI D.A.garcia-OrTIZ V.rUIZ-cOrTES H.-g.rUBAHN V.cOELLO cIcESE Unidad MonterreyAlianza Centro 504PIITApodacaNL 66629Mexico catedras cONAcYT-centro de Investigaciones enoptica Alianza Centro 504PIITApodacaNL 66629Mexico Mads clausen Institute University of Southern DenmarkNanoSYDAlsion 2 DK6400S?nderborgDenmark cIcFIM-UANL Av Universidad S/NSan Nicolas de los GarzaNL 66450Mexico Departamento deoptica CICESEEnsenadaBC 22860Mexico

We present a new design of a plasmonic Luneburg lens made from a gradient-index metasurface that was constructed with an array of nanometer-sized holes in a dielectric thin film. The fabricated structure consists of a planar lens with a diameter of 8.7 μm composed of a rectangular array of holes with a periodicity of 300 nm. The experimental characterization includes leakage-radiation microscopy imaging in the direction and frequency space. The former allows for characterization of the point spread function and phase distribution,whereas the latter grants access to qualitative measurements of the effective mode indices inside the plasmonic lens. The experimental results presented here are in good agreement with the expected average performance predicted by the numerical calculations. Nevertheless, the robustness of the characterization techniques presented here is also exploited to determine deviations from the design parameters.

关键词： space. film. characterization

Isolation and characterization of cellulose Nanofibers from Argentine Tacuara cane(guadua Angustifolia Kunth)

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Journal of renewable Materials 2019年第4期7卷 373-381页

作者： c.A.rodríguez ramírez Fleur rol Julien Bras Alain Dufresne Nancy Lis garcia Norma D'Accorso Universidad de Buenos Aires Facultad de Ciencias Exactas y NaturalesDepartamento de Química OrgánicaBuenos Aires Argentina cONIcET-Universidad de Buenos Aires.centro de Investigación en Hidratos de carbono(cIHIDEcAr).Buenos Aires Argentina Univ.grenoble Alpes CNRSGrenoble INPLGP2F-38000France

New trends in the area of material improvement are the use of natural nano-charges from renewable biomass,improving the value and sustainability of our country’s natural *** is widely used in many countries of the world,although in Argentina,despite being commercialized and exported for the manufacture of wood floors,it goes unnoticed despite having native ***,researchers identified the native and exotic species present in our country and are working on novel *** this context,it is proposed the Argentine Tacuara cane(guadua Angustifolia Kunth),endemic plant as a new source of nanocellulosic materials,where stem fibers have been isolated using a green method achieving with yield of 45.9%of *** cellulose nanofibrils(cNF)were obtained using a green homogenization *** cNF exhibited web-like long fibrous structure with the diameter of 10-20 *** crystallinity was 65.5%,as for the onset temperature of thermal decomposition was 212°*** nanocellulose isolated from the Tacuara cane seed fibers has a high potential to be used as a new source of cellulose-based nanofiller for the reinforcement of bionanocomposite films.

关键词： cellulose nanofibers green valorization

LDH conversion films for active protection of AZ31 Mg alloy

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Journal of Magnesium and Alloys 2023年第1期11卷 201-216页

作者： B.Pillado B.Mingo r.del Olmo E.Matykina A.M.Kooijman Y.gonzalez−garcia r.Arrabal M.Mohedano Departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad ComplutenseMadrid 28040Spain Department of Materials University of ManchesterOxford RoadManchester M139PLUK Institute of Optoelectronics Military University of Technology2 Kaliskiego Str.Warsaw 00-908Poland Materials Science and Engineering Department Delft University of TechnologyMekelweg 2Delft 2628 CDthe Netherlands

Zinc aluminium(Zn-Al)and lithium aluminium(Li-Al)–layered double hydroxides(LDH)coatings with incorporated inhibitors(Li-,Mo-and W-based)were successfully synthesized on AZ31 Mg ***-Al LDH W and Li-Al LDH Li showed the highest corrosion resistance and were selected for further *** cross-section examination revealed a bi-layer structure composed of an outer part with loose flakes and a denser inner ***,FTIr,and XPS analysis confirmed the incorporation of the ***-treatments with corrosion inhibitors containing solutions resulted in the selective dissolution of the most external layer of the LDH coating,reducing the surface roughness,hydrophilicity and paint adhesion of the *** corrosion properties were confirmed by SVET evaluation for the Zn-Al LDH W *** proposed active corrosion mechanism involves the ion-exchange of aggressive cl-ions,deposition of hydroxides and competitive adsorption of W-rich corrosion inhibitors.

关键词： AZ31 Magnesium Layered double hydroxides corrosion inhibitors Active corrosion protection

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Myth and writing

Myth and writing

Effect of caffeine in the intraventricular hemorrhage of the preterm newborn

作者： J. Neil c. garcia.

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Neural regeneration research 2023年第9期18卷 1942-1943页

作者： Pilar Alves-Martinez Monica garcia-Alloza Division of Physiology School of MedicineUniversidad de CadizCadizSpain Biomedical research and Innovation Institute of cádiz(INiBIcA)research Unit Puerta del Mar University Hospital University of CadizCadizSpain

There are around 15 million preterm newborns(PT) eve ry year(Atienza-Navarro et al., 2020).With these figures in mind,prematurity represents a major health problem worldwide and it is a leading cause of infant mortality,accounting for up to 35%of all deaths among newborns(Atienza-Navarro et al.,2020) and up to 18% of the deaths among children under 5 years of age.

关键词： newborn infant deaths

Understanding the immune response and the current landscape of immunotherapy in pancreatic cancer

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World Journal of gastroenterology 2021年第40期27卷 6775-6793页

作者： Lorena Ostios-garcia Julia Villamayor Esther garcia-Lorenzo David Vinal Jaime Feliu Department of Oncology La Paz University HospitalIDIPAZCIBERONCCátedra UAMAMGENMadrid 28046Spain

Pancreatic ductal adenocarcinoma(PDAc)is an aggressive tumor with high *** with surgery,radiotherapy,chemotherapy,and other locoregional or systemic therapies,the survival rates for PDAc are low and have not significantly changed in the past *** special characteristics of the PDAc’s microenvironment and its complex immune escape mechanism need to be considered when designing novel therapeutic approaches in this *** is characterized by chronic inflammation with a high rate of tumor-associated macrophages and myeloid-derived suppressor cells and a low rate of natural killer and effector T *** pancreatic microenvironment is a fibrotic,microvascularized stroma that isolates the tumor from systemic ***,a novel approach that has demonstrated effectiveness in certain solid tumors,has failed to show any practice-changing results in pancreatic cancer,with the exception of PDAcs with mismatch repair deficiency and high tumor mutational burden,which show prolonged survival rates with ***,numerous clinical trials are attempting to assess the efficacy of immunotherapeutic strategies in PDAc,including immune checkpoint inhibitors,cancer vaccines,and adoptive cell transfer,alone or in combination with other immunotherapeutic agents,chemoradiotherapy,and other targeted therapies.A deep understanding of the immune response will help in the development of new therapeutic strategies leading to improved clinical outcomes for patients with PDAc.

关键词： Pancreatic cancer Immunity Immune evasion Tumor microenvironment Immunotherapy cancer vaccines

Micro- and nanoporous materials capable of absorbing solvents and oils reversibly： the state of the art

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Petroleum Science 2017年第1期14卷 84-104页

作者： Javier S. Acevedo cortez Boris I. Kharisov Thelma E. Serrano Quezada Tomas c. Hernandez garcia Facultad de ciencias Qufmicas Universidad Autonoma de Nuevo Leon Ave. Universidad s/n66455 San Nicolas de los Garza NL Mexico

Treatment of petroleum spills and organic solvent pollution in general is an important issue; several techniques are under development to remove oil from water. The use of absorbents is one of the most common techniques to tackle this problem. These absorbents can be classified based on their characteristics of recyclability into irreversible and reversible ones. In this review, we discuss the application of several materials as oil absorbents, according to their classification and characteristics such as hydrophobicity, surface area and oil absorption capacity. Also, the fabrication methods for some materials are presented and analyzed.

关键词： Oil spills - composites reversibility Aerogels - Natural absorbents Micro- and nanoporousmaterials