Forest restoration projects involving active planting should prioritize species that are useful to local communities, while also considering species' threat status and resistance to local stress ...factors, but scientific knowledge on these criteria is scarce, especially in understudied tropical ecosystems. We hypothesized that local ecological knowledge can help to fill this gap. Through interviews with 47 local experts and 197 randomly selected households in 8 rural communities of the tropical dry forests of northwestern Peru and southern Ecuador, we identified the species perceived as most useful, most threatened, and most resistant to local stress factors. To better understand the studied local ecological knowledge, we also explored the following research questions and their implications for species selection decisions: (1) How does species' potential usefulness compare to their active use? (2) How does species' perceived threat status relate to their usefulness? (3) Does local knowledge on species' resistance to local stress factors corroborate scientific knowledge? We found large differences between the potential and active use of species and illustrate how data on both can yield useful insights. Furthermore, we found that species' perceived threat status was mainly linked to their usefulness for construction wood, and that the vast majority of local perceptions on species' threat status and stress resistance coincided with scientific knowledge. Our findings illustrate the large potential of local ecological knowledge for improving species selection strategies and thereby increasing the success of forest restoration efforts worldwide.
In spite of the widespread use of the chemical reduction method to obtain silver nanoparticles, the nanoparticle yield is often low due to a required addition of small volumes of diluted metal ions ...to a solution containing a reducer. Higher yields can be obtained following an alternative method, in which the reducer is added to a greater volume of silver ions in the solution. In this study, protocols for both methods are detailed and compared, using characterization tools such as UV-vis spectrometry, dynamic light scattering (DLS), and zeta potential measurements. By using this alternative method, the amount of silver in the solution is three times greater, and nanoparticles with a narrower size distribution are formed (between 6 and 70 nm in size). In contrast, the regular method produces particles of 3 and 100 nm. Zeta potential measurements indicate that the nanoparticles synthesized with the alternative method will be more stable than those from the regular method.
Nanotechnology and its applications to medicine, known as nanomedicine, involve a wide use of nanomaterials to stimulate and guide the regenerative properties of cells. In particular, tissue ...regeneration can be promoted by enabling a controlled release of therapeutic agents, which can be done using nanoparticles. In this review article, the fundamentals of tissue regeneration are discussed, focusing on epithelial tissue, to demonstrate the importance of delivering therapeutic agents in an efficient, sustained and localized manner. Then, the methods for synthesizing metallic and polymeric nanoparticles are described. While polymeric nanoparticles can be loaded with an agent during synthesis, metallic nanoparticles must first be synthesized to later interact with therapeutic agents. This interaction can be fine-tuned by functionalizing metallic nanoparticles with organic molecules, which results in a more controlled attachment.This review highlights the importance of choosing the appropriate method of synthesis and functionalization, which must be designed considering both the type of tissue to regenerate and the nature of the agent to be transported.
Strategies to design novel antibacterial materials may rely on the combination of materials to achieve synergistic effects. The coupling of antibacterial peptides to nanoparticles, however, needs to ...be directed conveniently to avoid structural changes within the peptide and/or degradation of the nanoparticle. Here, we present the results of the attachment of a synthetic peptide (VIHGW-alkyne-G-NH
2
) containing the amino terminal copper and nickel (ATCUN) motif to silver nanoparticles. In order to direct the peptide-nanoparticle coupling, the peptide was functionalized with an alkyne, whereas the nanoparticles were functionalized with azide groups using thiol-polyethylene glycol-azide (HS-PEG-N
3
) chains, so that the acetylide and the azide can undergo a click reaction. The reaction was conducted at room temperature and the steps in the construction of the nanoparticle-PEG-ATCUN array were followed by a combination of UV-Vis absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy. Evidence of the attachment of the PEG molecules through the thiol termination indicates that the nanoparticle is functionalized with azide groups, although only partially. The click reaction with the synthetic peptide is evidenced by the loss of the N
3
-vibrational signal with infrared spectroscopy. Throughout the steps of the synthesis, the behavior of the nanoparticles was followed by UV-Vis spectroscopy, dynamic light scattering, and zeta potential measurements, observing that during the process there are no significant changes in the size of the nanoparticle and that the stability of the nanoparticles increases. Antibacterial tests, conducted using
E. coli
, showed that the activity of the Ag-PEG-ATCUN nanocomposites is higher than that of nanoparticles and ATCUN peptides separately.
Graphical abstract
Los bosques estacionalmente secos del Perú Linares-Palomino, Reynaldo; Huamantupa-Chuquimaco, Isau; Padrón, Eva ...
Revista peruana de biología,
11/2022, Letnik:
29, Številka:
4
Journal Article
Odprti dostop
Los bosques estacionalmente secos en el Perú constituyen un conjunto de ecosistemas que incluye tres grandes grupos florísticos: bosques costeros, interandinos y orientales. Con la excepción de los ...bosques estacionalmente secos de las llanuras costeras del norte del país, hasta hace poco la ausencia de datos hacía difícil describir adecuadamente estos grupos en base a su florística. En los últimos 20 años, en estos bosques se han generado diversos estudios florísticos e inventarios botánicos enfocados en plantas leñosas, que han llenado vacíos de conocimiento en áreas críticas. Con estos estudios hemos generado la base de datos DRYFLOR Perú que a la fecha incluye 526 inventarios cuantitativos (listas de especies en áreas discretas incluyendo registros de sus abundancias) y que nos permiten confirmar la distinción florística de los tres grandes grupos. Adicionalmente logramos reconocer claramente dos subgrupos de bosques estacionalmente secos costeros (de llanura y de montaña), dos subgrupos interandinos (valles del Marañón-Mantaro y del Pampas) y tres subgrupos orientales (valles del Huallaga, Tambo y Urubamba). Todos los subgrupos tienen un ensamblaje de especies de plantas leñosas que los distingue y caracteriza en términos de abundancia, frecuencia, riqueza de especies y niveles de endemismo. Si bien ahora podemos describir mejor la heterogeneidad florística de los bosques estacionalmente secos en el Perú, hemos identificado vacíos de conocimiento importantes que requieren de atención prioritaria: i) requerimos de esfuerzos de inventario adicionales en los bosques orientales, ii) necesitamos resolver las afinidades florísticas de los bosques del valle del Apurímac, iii) nuestros datos coinciden en poco más del 75% con las definiciones y distribución de bosques secos del reciente Mapa Nacional de Ecosistemas del Perú, y será necesario revisar el concepto de bosque estacionalmente seco para lograr capturar adecuadamente su distribución en este instrumento de gestión.
Seasonally dry forests in Peru are a combination of ecosystems that include three large floristic groups: coastal, inter-Andean and eastern forests. Except for the seasonally dry forests of the ...northern coastal plains of the country, until recently it was difficult to explore what occurred floristically within each group due to lack of data. However, in the last 20 years various floristic studies and botanical inventories focused on woody plants have managed to fill knowledge gaps in critical areas. With these studies we have generated the DRYFLOR Peru database that to date includes 526 quantitative inventories (lists of species in discrete areas, including records of their abundances) and that allows us to confirm the floristic distinction of the three large groups. Additionally, we were able to clearly recognize two subgroups of seasonally dry coastal forests (on coastal plains and along the Andean piedmont), two inter-Andean subgroups (within the Maranon-Mantaro and Pampas valleys) and three eastern subgroups (within the Huallaga, Tambo and Urubamba valleys). All subgroups have an assemblage of woody plant species that distinguishes and characterizes them in terms of abundance, frequency, species richness, and levels of endemism. Although we can now better describe the floristic heterogeneity of seasonally dry forests in Peru, we have identified important knowledge gaps that require urgent attention: i) we require additional inventory efforts in the eastern forests, ii) we need to resolve the floristic affinities of the forests of the Apurimac valley, iii) our data agree in little more than 75% with the definitions and distribution of dry forests of the recent National Ecosystem Map of Peru, and it will be necessary to review the concept of seasonally dry forests to adequately capture its distribution in this management tool.
Uno de los desafíos en la implementación del uso de nanopartículas metálicas como vehículos;
de proteínas es la falta de metodologías de formación de compuestos del tipo nanopartículaproteína que ...permitan mantener la actividad biológica de dichas biomoléculas. En esta investigación, se presenta una metodología para la síntesis de nanopartículas de plata, las cuales;
se caracterizan por su facilidad de síntesis, biocompatibilidad y su naturaleza antimicrobiana,;
a altas concentraciones y su interacción con una proteína estándar, la albúmina de suero bovino;
(BSA, del inglés bovine albumin serum), y con factor de crecimiento epidermal (EGF, del;
inglés epidermal growth factor), la cual es una proteína de interés para la regeneración de tejido;
epitelial. La interacción nanopartícula-proteína ha sido caracterizada mediante espectroscopía;
UV-Visible, espectroscopía infrarroja por transformada de Fourier (FTIR, del inglés fouriertransform infrared spectroscopy), dispersión dinámica de luz (DLS, del inglés dynamic light;
scattering), potencial zeta (ZP, del inglés zeta potential) y microscopía electrónica de;
transmisión (TEM, del inglés transmission electron microscopy). La evaluación de la actividad;
antibacterial fue evaluada en cultivos de Escherichia coli. Se demostró que con un tiempo de;
reacción de 20 minutos y una concentración inicial de 1.0 mM de nitrato de plata, AgNPs de;
33 mM con una baja distribución en longitud de onda máxima y absorbancia eran obtenidas.;
Además, bajo la metodología desarrollada una relación molar de 0.018 BSA:AgNPs fue;
encontrada óptima para una mayor interacción entre BSA nativo y las AgNPs. Por último, dicha;
metodología fue extrapolada para la interacción de AgNPs con 1000, 2500 y 4000 ng rh EGF,;
encontrando una mayor eficiencia de carga, mayor velocidad de liberación y una mayor;
estabilidad de la proteína usando 4000 ng rh EGF. Los ensayos antibacteriales mostraron que;
la actividad antibacterial se mantuvo en las AgNPs en interacción con rh EGF aunque en menor;
escala en comparación con las AgNPs puras.
Consejo Nacional de Ciencia y Tecnología (Perú). Fondo Nacional de Desarrollo Científico y ;
Tecnológico (Fondecyt)
Tesis
Water quality in rivers is affected as it passes through urban areas; this situation can be improved with good management of water resources. High Andean rivers require further studies to indicate ...their quality status. In addition, it is important to estimate the health risks associated with exposure to contaminants in the river water. Therefore, it is proposed to assess the Water Quality Index (WQI) using the National Sanitation Foundation (NSF) model and the health risks in the urban section of the Ichu River in Peru. Six monitoring points were selected in the section of the Ichu River that includes the urbanized part of the city of Huancavelica. The sample was taken during the months of February to April 2021. Critical parameters were analyzed by multivariate statistical analysis as principal components and cluster test. In addition, Pearson's correlation test was performed, and the water quality status was evaluated using the WQI-NSF model. The Ichu River was of "bad" quality, unfit for human consumption, and confirming the impact of the population on water quality. The WQI-NSF model could be useful for high Andean watercourses suffering from anthropogenic deterioration of quality, with illegal effluent discharges and poor sanitation. There is a high health risk due to fecal coliform contamination from sewage discharges into the river. In addition, the total hazard index indicated that contaminants are causing negative health effects in adult males at a low risk level (risk 2), adult females at a moderate risk level (risk level 3), and children at a negligible risk level (risk level 1). With the help of this study, an appropriate management plan can be put in place to restore the ecological integrity of the Ichu River.
Aim
To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and ...hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser‐availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource‐availability hypothesis).
Time period
Tree‐inventory plots established between 1934 and 2019.
Major taxa studied
Trees with a diameter at breast height (DBH) ≥ 9.55 cm.
Location
Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield.
Methods
We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree‐inventory plots across terra‐firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance‐weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes.
Results
Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra‐firme forests (excluding podzols) compared to flooded forests.
Main conclusions
The disperser‐availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types.
In developing countries, river monitoring is very limited. Despite environmental and health problems, there is a paucity of information regarding the contaminants phosphates and nitrates. Thus, ...concentration and health risks, of phosphates and nitrates of the Ichu river waters, in Huancavelica, Peru, were evaluated. Sampling was carried out at six different points. Important water quality parameters were analyzed, such as pH, Temperature, Dissolved oxygen (DO) and electric conductivity (EC). The results revealed that the phosphate and nitrate varied between 0.475 to 0.575 mg/L and 11.10 to 14.00 mg/L, respectively. The concentration of phosphates and nitrates was 0.520±0.02 mg/L and 13.10±0.48, respectively. The Ichu River water had the quality that corresponded to its category, when compared to the permitted limits of the Environmental Quality Standards (EQS) for water. It did not present contamination according to the nutrient contamination index and the health risk was from chronic low intake. Besides, it presented a moderate relationship between nitrate and phosphate, due to the low concentration of phosphates during the dry season. What is new about this research is the approach to potential health risks of exposure to nitrates and phosphates, in a high Andean river in Huancavelica, Peru.
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