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Selective logging alters allometric relationships of five tropical tree species in seasonal semi-deciduous forests

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Journal of Forestry Research 2019年第5期30卷 1633-1639页

作者： Diego Resende Rodrigues Yves rafael Bovolenta José Antonio Pimenta Edmilson Bianchini Departamento de Biologia Animal e Vegetal Centro de Ciências Biológicas Universidade Estadual de Londrina

In selectively logged forests,trees are more likely to expand their diameters(D)at the expense of height(H)growth,resulting in variations in H:D relationships.This study examines how selective logging affects the H:D allometric relationships of five common tree species and whether the effects vary with functional groups(shade-intolerant or shade tolerant)in seasonal semi-deciduous forests.Individuals of five species in a 3000 m^2(0.3 ha)plot were marked and heights and diameters recorded.most of the species,with one exception,showed greater investment in diameter per increment of height compared to an unlogged forest,possibly because of the greater light available.This study shows the effects of selective logging on species populations as evidenced by increases in H:D ratios.Comparison of forest fragments with different degrees of human impact is important because it allows us to understand the differences in architectural characteristics caused by selective logging.

关键词： Allometry Anthropic exploitation Ecological groups Luminosity Selective logging

Enhanced Catalytic Activity of Gold@Polydopamine Nanoreactors with multi-compartment Structure Under NIR Irradiation

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Nano-micro Letters 2019年第4期11卷 469-484页

作者： Shilin mei Zdravko Kochovski rafael Roa Sasa Gu Xiaohui Xu Hongtao Yu Joachim Dzubiella matthias Ballauff Yan Lu Soft matter and Functional materials Helmholtz-Zentrum Berlin für Materialien und EnergieHahn-Meitner Platz 114109 BerlinGermany Department of Applied Physics I University of Málaga29071 MálagaSpain College of materials Science and Engineering Nanjing Tech UniversityNanjing 210000People’s Republic of China Institute of Physics University of Freiburg79104 FreiburgGermany Simulation of Energy materials Helmholtz-Zentrum Berlin für Materialien und EnergieHahn-Meitner Platz 114109 BerlinGermany Institut für Physik Humboldt-Universitat zu BerlinNewtonstr.1512489 BerlinGermany Institute of Chemistry University of Potsdam14476 PotsdamGermany

Photothermal conversion(PTC)nanostructures have great potential for applications in many fields,and therefore,they have attracted tremendous attention.However,the construction of a PTC nanoreactor with multi-compartment structure to achieve the combination of unique chemical properties and structural feature is still challenging due to the synthetic difficulties.Herein,we designed and synthesized a catalytically active,PTC gold(Au)@polydopamine(PDA)nanoreactor driven by infrared irradiation using assembled PS-b-P2VP nanosphere as soft template.The particles exhibit multi-compartment structure which is revealed by 3D electron tomography characterization technique.They feature permeable shells with tunable shell thickness.Full kinetics for the reduction reaction of 4-nitrophenol has been investigated using these particles as nanoreactors and compared with other reported systems.Notably,a remarkable acceleration of the catalytic reaction upon near-infrared irradiation is demonstrated,which reveals for the first time the importance of the synergistic effect of photothermal conversion and complex inner structure to the kinetics of the catalytic reduction.The ease of synthesis and fresh insights into catalysis will promote a new platform for novel nanoreactor studies.

关键词： Gold@polydopamine 3D tomography Nanoreactor Catalysis Photothermal conversion

Paclitaxel-loaded hollow-poly（4-vinylpyridine） nano- particles enhance drug chemotherapeutic efficacy in lung and breast cancer cell lines

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Nano Research 2017年第3期10卷 856-875页

作者： rafael Contreras-Caceres maria C. Leiva Raul Ortiz Amelia Diaz Gloria Perazzoli miguel A.Casado-Rodriguez Consolacion melguizo Jose m. Baeyens Juan m. Lopez-Romero Jose Prados Department of Organic Chemistry Faculty of Science University of Mdlaga 29071 Malaga Spain Institute of Biopathology and Regenerative medicine (IBImER) Center of Biomedical Research (CIBM) University of Granada 18100 Granada Spain Department of Anatomy and Embryology Faculty of Medicine University of Granada 18071 Granada Spain Biosanitary Institute of Granada (IBS. GRANADA) SAS-Universidad de Granada 18014 Granada Spain Department of Health Science University of Jaen 23071 Jadn Spain Department of Pharmacology Institute of Neuroscience Biomedical Research Center (CIBM) University of Granada 18100 Granada Spain

Paclitaxel （PTX）, one of the most effective cytotoxins for the treatment of breast and lung cancer, is limited by its severe side effects and low tumor selectivity. In this work hollow-poly（4-vinylpyridine）（hollow-p4VP） nanoparticles （NPs） have been used for the first time to generate PTX@p4VP NPs, employing a novel technique in which a gold core in the center of the NP is further oxidized to produce the hollow structure into which PTX molecules can be incorporated. The hollow-p4VP NPs exhibit good physicochemical properties and displayed excellent biocompatibility when tested on blood （no hemolysis） and cell cultures （no cytotoxicity）. Interestingly, PTX@p4VP NPs significantly increased PTX cytotoxicity in human lung （A-549） and breast （mCF-7） cancer cells with a significant reduction of PTX ICs0 （from 5.9 to 3.6 nm in A-549 and from 13.75 to 4.71 nm in mCF-7）. In addition, PTX@p4VP caused a decrease in volume of A-549 and mCF-7 multicellular tumor spheroids （mTS）, an in vitro system that mimics in vivo tumors, in comparison to free PTX. This increased antitumoral activity is accompanied by efficient cell internalization and increased apoptosis, especially in lung cancer mTS. Our results offer the first evidence that hollow- p4VP NPs can improve the antitumoral activity of PTX. This system can be used as a new nanoplatform to overcome the limitations of current breast and lung cancer treatments.

关键词： paclitaxel,poly（4-vinylpyridine）（p4VP） nanoparticles,lung cancer,breast cancer,cytotoxicity,multicellular tumorspheroids

Appropriate search techniques to estimate Weibull function parameters in a Pinus spp.plantation

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Journal of Forestry Research 2021年第6期32卷 2423-2435页

作者： Lais Almeida Araujo rafael menali Oliveira mario Dobner Jr Carolina Souza Jarochinskie Silva Lucas Rezende Gomide Department of Forest Sciences Federal University of LavrasLavrasMinas GeraisBrazil Department of Agriculture Biodiversity and ForestsFederal University of Santa CatarinaCuritibanosSanta CatarinaBrazil

The Weibull function,a continuous probability distribution,is widely used for diameter distribution modelling,in which parameter estimation performance is affected by stand attributes and fitting methods.The Weibull cumulative distribution function is nonlinear,and classical fitting methods may provide a not optimal solution.Invoking the use of artificial intelligence by metaheuristics is reasonable for this optimisation task.Therefore,aimed and compared(1)the metaheuristics genetic algorithm and simulated annealing performance over the moment and percentile methods;(2)the hybrid strategy merging the metaheuristics tested and the percentile method and,(3)the metaheuristics fitness functions under basal area and density errors.A long-term experiment in a Pinus taeda stand subjected to crown thinning was used.According to our findings,all methods have a similar performance,independent of the thinning regimes and age.The pattern of the estimated parameters tends to be acceptable,as b increases over time and c increases after thinning.Overall,our findings suggest that methods based on metaheuristics have a higher precision than classical methods for estimating Weibull parameters.According to the classification test,the methods that involved simulated annealing stood out.The hybrid method involving this metaheuristic also stood out,with accurate estimates.Classical methods showed the poorest performance,and we therefore suggest the use of simulated annealing due to its faster processing time and high-quality solution.

关键词： Forest management Diameters distribution Weibull function Genetic algorithm Simulated annealing

Chemically Induced and Light-Independent Cryptochrome Photoreceptor Activation

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molecular Plant 2008年第1期1卷 4-14页

作者： Gesa Rosenfeldt rafael munoz Viana Henning D. mootz Albrecht G. von Arnim Alfred Batschauera FB Biologie-pflanzenphysiologie Philipps-Universitat Karl-von-Frisch-Str. 8 35032 Marburg Germany Universitat Dortmund FB Chemie-Chemische Biologie Otto-Hahn-Str. 6 44227 Dortmund Germany University of Tennessee Department of Biochemistry Cellular and Molecular Biology Waiters Life Sciences M407 Knoxville TN 37996-0840 USA

The cryptochrome photoreceptors of higher plants are dimeric proteins. Their N-terminal photosensory domain mediates dimerization, and the unique C-terminal extension （CCT） mediates signaling. We made use of the human FK506binding protein （FKBP） that binds with high affinity to rapamycin or rapamycin analogs （rapalogs）. The FKBP-rapamycin complex is recognized by another protein, FRB, thus allowing rapamycin-induced dimerization of two target proteins. Here we demonstrate by bioluminescence resonance energy transfer （BRET） assays the applicability of this regulated dimer- ization system to plants. Furthermore, we show that fusion proteins consisting of the C-terminal domain of Arabidopsis cryptochrome 2 fused to FKBP and FRB and coexpressed in Arabidopsis cells specifically induce the expression of cryptochrome-controlled reporter and endogenous genes in darkness upon incubation with the rapalog. These results demonstrate that the activation of cryptochrome signal transduction can be chemically induced in a dose-dependent fashion and uncoupled from the light signal, and provide the groundwork for gain-of-function experiments to study specifically the role of photoreceptors in darkness or in signaling cross-talk even under light conditions that activate members of all photoreceptor families.

关键词： C-terminal extension (CCT) FK506-binding protein (FKBP) bioluminescence resonance energy transfer (BRET)

Tumor-induced neurogenesis and immune evasion as targets of innovative anti-cancer therapies

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1584-1606页

作者： Rodolfo Daniel Cervantes-Villagrana Damaris Albores-García Alberto rafael Cervantes-Villagrana Sara Judit García-Acevez Department of Pharmacology Center for Research and Advanced Studies of the National Polytechnic Institute(CINVESTAV-IPN)07360 Mexico CityMexico Department of Environmental Health Sciences Florida International University(FIU)MiamiFlorida 33199USA Laboratorio de investigación en Terapéutica Experimental Unidad Académica de Ciencias QuímicasÁrea de Ciencias de la SaludUniversidad Autónoma de Zacatecas(UAZ)ZacatecasMéxico Dirección de Proyectos e Investigación Grupo Diagnóstico Médico Proa06400 CDMX CuauhtémocMéxico

Normal cells are hijacked by cancer cells forming together heterogeneous tumor masses immersed in aberrant communication circuits that facilitate tumor growth and dissemination.Besides the well characterized angiogenic effect of some tumor-derived factors;others,such as BDNF,recruit peripheral nerves and leukocytes.The neurogenic switch,activated by tumor-derived neurotrophins and extracellular vesicles,attracts adjacent peripheral fibers(autonomic/sensorial)and neural progenitor cells.Strikingly,tumor-associated nerve fibers can guide cancer cell dissemination.moreover,IL-1β,CCL2,PGE2,among other chemotactic factors,attract natural immunosuppressive cells,including T regulatory(Tregs),myeloid-derived suppressor cells(mDSCs),and m2 macrophages,to the tumor microenvironment.These leukocytes further exacerbate the aberrant communication circuit releasing factors with neurogenic effect.Furthermore,cancer cells directly evade immune surveillance and the antitumoral actions of natural killer cells by activating immunosuppressive mechanisms elicited by heterophilic complexes,joining cancer and immune cells,formed by PD-L1/PD1 and CD80/CTLA-4 plasma membrane proteins.Altogether,nervous and immune cells,together with fibroblasts,endothelial,and bone-marrow-derived cells,promote tumor growth and enhance the metastatic properties of cancer cells.Inspired by the demonstrated,but restricted,power of anti-angiogenic and immune cell-based therapies,preclinical studies are focusing on strategies aimed to inhibit tumor-induced neurogenesis.Here we discuss the potential of anti-neurogenesis and,considering the interplay between nervous and immune systems,we also focus on anti-immunosuppression-based therapies.Small molecules,antibodies and immune cells are being considered as therapeutic agents,aimed to prevent cancer cell communication with neurons and leukocytes,targeting chemotactic and neurotransmitter signaling pathways linked to perineural invasion and metastasis.

关键词： PD1 therapies invasion

Three-dimensional mapping and comparative analysis of the distal human corpus cavernosum and the inflatable penile prosthesis

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Asian Journal of Andrology 2013年第4期15卷 567-570,I0012页

作者： Tariq S Hakky Daniel Ferguson Philippe E Spiess Paul Bradley Tom FLue rafael E Carrion Department of Urology University of South Florida Tampa General Circle Tampa FL 33602 USA 23D3Solutions Burnaby BCV5J 5M8 Canada and Department of Urology University of Southern California San Francisco 400 Parnassus Ave San Francisco CA 94143 USA

The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional （3D） scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios mesh software, and GOm Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm （36.01-37.0 mm）, which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip.

关键词： corpus cavernosum penile prosthesis three-dimensional analysis

Refractive index measurement of dielectric samples using highly focused radially polarized light(Invited Paper)

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Chinese Optics Letters 2017年第3期15卷 12-15页

作者： Guadalupe López-morales Victor-manuel Rico-Botero rafael Espinosa-Luna Qiwen Zhan GIPYS Laboratory Centro de Investigaciones en Optica A. C. León Gto 37150 México Department of Electro-Optics and Photonics University of Dayton Dayton OH 45469 USA

In this Letter, a refractive index measurement of a dielectric sample using highly focused radially polarized light is reported. Through imaging analysis of the optical field at the pupil plane of a high numerical aperture （NA） objective lens reflected by the sample under study, the Brewster angle is found. Employing a high NA objective lens allows the measurement of multiple angles of incidence from 0° to 64° in a single shot. The refractive index of the sample is estimated using the measured Brewster angle. The experimental results are compared with the theoretical images computed with the Fresnel theory, and a good agreement is obtained.

关键词： high Refractive index measurement of dielectric samples using highly focused radially polarized light

Bioinformatics Analysis of NprR-NprX Quorum-Sensing System of <i>Bacillus thuringiensis</i>Isolates from the Papaloapan Region, Oaxaca-mexico

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Advances in Biological Chemistry 2015年第7期5卷 293-304页

作者： Humberto rafael Bravo-D Alain Cruz-Nolasco Luis Raúl Gutiérrez-Lucas Ana Karin navarro-mtz División de Estudios de Posgrado Universidad del Papaloapan Circuito Central 200 Parque Industrial Tuxtepec Oaxaca México Instituto de Biotecnología Universidad del Papaloapan Circuito Central 200 Parque Industrial Tuxtepec Oaxaca México

Quorum sensing is a chemical communication process that bacteria use to regulate collective behaviors. In Gram-positive bacteria, oligopeptides (called autoinducers) are the signaling molecules to elicit quorum sensing. In Bacillus thuringiensis, NprR is a transcriptional regulator whose activity depends on the NprX signalling peptide. Bacillus thuringiensis is closely related to Bacillus cereus and Bacillus anthracis. The principal difference between them is that Bacillus thuringiensis is the only one that produced Cry protein. The aim of this study is to explore the relation of nprR and 16S rRNA genes in Bacillus thurin-giensis. Phylogenetic trees of nucleotide sequences of nprR and 16S rRNA genes were built. Sequences of fourteen new isolates from Papaloapan region were included in those phylo-genetic trees. In order to identify the isolates, a simple and fast methodology considering the Cry protein formation was used. The 16S rRNA phylogenetic tree allows identify eight isolates as Bacillus thuringiensis and the others as Bacillus spp. The nprR phylogenetic tree does not match with the 16S rRNA phylogenetic tree. This confirms that nprR is not a molecular marker for evolution. most of the new isolates have the same NprR sequence (WTSDIVG). However, the SKPDIVG is the most common NprR sequence in thuringiensis species.

关键词： Quorum-Sensing Bacillus thuringiensis NprR-NprX Phylogenetic Tree