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1.
Mar Environ Res ; 193: 106254, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37979404

RESUMEN

Corals provide a complex 3D framework that offers habitat to diverse coral reef fauna. However, future reefs are likely to experience reduced coral abundance. Sponges have been proposed as one potential winner on future coral reefs, but little is known of how they contribute to reef 3D structure. Given the ecological importance of structural complexity, it is critical to understand how changes in the abundance of structure-building organisms will affect the three-dimensional properties of coral reefs. To investigate the potentially important functional role of coral reef sponges as providers of structural complexity, we compared the structural complexity of coral- and sponge-dominated areas of an Indonesian coral reef, using 3D photogrammetry at a 4 m2 spatial scale. Structural complexity of 31 4 m2 quadrats was expressed as rugosity indicating reef contour complexity (R), vector dispersion indicating heterogeneity of angles between reef surfaces (1/k), and fractal dimension indicating geometrical complexity at five different spatial scales between 1 and 120 cm (D1-5). Quadrats were identified as high- or low-complexity using hierarchical clustering based on the complexity metrics. At high structural complexity, coral- and sponge-dominated quadrats were similar in terms of R and 1/k. However, smallest-scale refuge spaces (1-5 cm) were more abundant in coral-dominated quadrats, whereas larger scale refuge spaces (30-60 cm) were more abundant in sponge-dominated quadrats. Branching and massive corals contributed the most to structural complexity in coral-dominated quadrats, and barrel sponges in sponge-dominated quadrats. We show that smaller-scale refugia (1-5 cm) are reduced on sponge-dominated reefs at the spatial scale considered here (4 m2), with potential negative implications for smaller reef fauna.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Ecosistema
2.
Membranes (Basel) ; 12(11)2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36363600

RESUMEN

This is part 2 of the research on pervaporation membranes for seawater desalination based on Geo-rGO-TiO2 nanocomposite. The quality of the Geo-rGO-TiO2 pervaporation membranes (PV), as well as the suitability of the built pervaporation system, is thoroughly discussed. The four membranes described in detail in the first article were tested for their capabilities using the parameters turbidity, salinity, total suspended solids (TSS), and electrical conductivity (EC). The membranes' flux permeate was measured as a function of temperature, and salt rejection was calculated using the electrical conductivity values of the feed and permeate. Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) techniques were used to investigate changes in the chemical composition and internal structure of the membranes after use in pervaporation systems. The morphology of the membrane's surfaces was examined by means of scanning electron microscopy (SEM), and the elemental distribution was observed by using X-ray mapping and energy dispersive spectroscopy (EDS). The results showed that the pervaporation membrane of Geo-rGO-TiO2 (1, 3) achieved a permeate flux as high as 2.29 kg/m2·h with a salt rejection of around 91%. The results of the FTIR and XRD measurements did not show any changes in the functional group and chemical compositions of the membrane after the pervaporation process took place. Long-term pressure and temperature feed cause significant cracking in geopolymer and Geo-TiO2 (3) membranes. SEM results revealed that the surface of all membranes is leached out, and elemental distribution based on X-ray mapping and EDS observations revealed the addition of Na+ ions on the membrane surface. The study's findings pave the way for more research and development of geopolymers as the basic material for inorganic membranes, particularly with the addition of rGO-TiO2 nanocomposites.

3.
Membranes (Basel) ; 11(12)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34940467

RESUMEN

This is the first of two papers about the synthesis and microstructure properties of the Geo-rGO-TiO2 ternary nanocomposite, which was designed to suit the criteria of a pervaporation membrane for seawater desalination. The performance and capability of Geo-rGO-TiO2 as a seawater desalination pervaporation membrane are described in the second paper. A geopolymer made from alkali-activated metakaolin was utilized as a binder for the rGO-TiO2 nanocomposite. A modified Hummer's method was used to synthesize graphene oxide (GO), and a hydrothermal procedure on GO produced reduced graphene oxide (rGO). The adopted approach yielded high-quality GO and rGO, based on Raman spectra results. The nanolayered structure of GO and rGO is revealed by Transmission Electron Microscopy (TEM) images. The Geo-rGO-TiO2 ternary nanocomposite was created by dispersing rGO nanosheets and TiO2 nanoparticles into geopolymer paste and stirring it for several minutes. The mixture was then cured in a sealed mold at 70 °C for one hour. After being demolded, the materials were kept for 28 days before being characterized. Fourier Transform Infrared (FTIR) and X-ray Diffraction (XRD) measurements revealed that the geopolymer matrix efficiently bonded the rGO and TiO2, creating nanocomposites. Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy (EDS) was used to examine the morphology of the outer layer and cross-sections of nanocomposites, and the results displayed that rGO were stacked on the surface as well as in the bulk of the geopolymer and will potentially function as nanochannels with a width of around 0.36 nm, while TiO2 NPs covered the majority of the geopolymer matrix, assisting in anti-biofouling of the membranes. The pores structure of the Geo-rGO-TiO2 were classified as micro-meso pores using the Brunauer-Emmet-Teller (BET) method, indicating that they are appropriate for use as pervaporation membranes. The mechanical strength of the membranes was found to be adequate to withstand high water pressure during the pervaporation process. The addition of rGO and TiO2 NPs was found to improve the hyropobicity of the Geo-rGO-TiO2 nanocomposite, preventing excessive seawater penetration into the membrane during the pervaporation process. The results of this study elucidate that the Geo-rGO-TiO2 nanocomposite has a lot of potential for application as a pervaporation membrane for seawater desalination because all of the initial components are widely available and inexpensive.

4.
Zootaxa ; 4996(1): 1-48, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34810546

RESUMEN

Sponges that excavate and inhabit calcareous substrate, predominantly of the Clionaidae, are widely distributed in marine habitats, but are particularly diverse and abundant on coral reefs. Unfortunately, their cryptic habit and difficult taxonomy mean respective taxa are poorly understood, and therefore they are rarely included in reef surveys. This is particularly true of the Southeast Asian Indo-Pacific, where a diverse faunistic record is contrasted with a very limited understanding of eco-physiological requirements of these sponges. In light of this, in situ surveys of the most common bioeroding sponges in the Wakatobi region of Southeast Sulawesi, Indonesia were conducted, followed by morphological and molecular analysis. The seven most common species in the Wakatobi included five species with a wide Indo-Pacific distribution and two new species. Four species, Cliona orientalis, Cliona aff. schmidtii, Spheciospongia cf. vagabunda trincomaliensis and Cliothosa hancocki have been previously reported from Indonesian waters, while Zyzzya criceta is a new record for Indonesia. Two brown sponges belonging to the Cliona viridis species complex, Cliona wakatobiensis sp. nov. and Cliona cribripora sp. nov., are here described as new to science. They were morphologically distinct from other species in the sample region and could not conclusively be allocated to any other known clionaid species. A maximum likelihood analysis of ITS1 rDNA revealed them to be phylogenetically closer to other Indo-Pacific species such as Cliona orientalis and Cliona thomasi than to other species within this taxon complex.


Asunto(s)
Arrecifes de Coral , Poríferos , Animales , ADN Ribosómico , Ecosistema , Indonesia
5.
J Oleo Sci ; 70(10): 1509-1515, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34615831

RESUMEN

Many studies have explored the pretreatment of lignocellulosic biomass based on oil palm empty fruit bunch (OPEFB) which is categorized as potential biomass waste for bioethanol production. Before proceeding further to obtain bioethanol, several steps such as pretreatment to increase organic constituents are needed. The ionic liquids (ILs) were commonly investigated by many researchers for lignocellulosic pretreatment because it is easy solubilization property, non-toxic, and not harmful impacts on the environment. Therefore in this study, the hypothesis and main objective were to observe the effectiveness of triethylammonium methanesulfonate ion liquid (TMS IL) in the OPEFB lignocellulose pretreatment process. Three variations were studied to obtain optimization of the pretreatment process, such as times duration, IL composition, and temperature. Based on these results, we observed the effectiveness of the time duration for OPEFB pretreatment of 20 hours. Furthermore, it was applied to determine the optimization of IL composition and temperature showing that using 91% (1:1:10) at 120°C for 20 hours has provided good performance for the OPEFB lignocellulose pretreatment process. TMS IL has exhibited the ability to reduce hemicellulose and lignin contents to 7.35% and 17.80%, whereas cellulose was increased by 54.24%. This has the opportunity to be projected to a larger scale for bioethanol production based on OPEFB lignocellulose.


Asunto(s)
Compuestos de Amonio/química , Biomasa , Etanol/síntesis química , Tecnología Química Verde , Líquidos Iónicos/química , Lignina/química , Mesilatos/química , Aceite de Palma/química , Solventes/química , Frutas/química , Eliminación de Residuos , Solubilidad , Temperatura , Factores de Tiempo
6.
Membranes (Basel) ; 10(12)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287149

RESUMEN

An ionic imprinted membrane (IIM) was synthesized using sulfonated polyeugenol, derived from eugenol, as its functional polymer and polysulfone as its base membrane for the selective adsorption of Au(III). This study aims to determine the adsorption of Au(III) metal ions using IIM compared with the non-imprinted membrane (NIM) and to figure out the membrane selectivity towards Au(III) in mixed solutions of Au/Cd, Au/Cu, and Au/Fe. IIM has a pore size of 0.767 µm while the non-imprinted membrane (NIM) has a pore size of 0.853 µm. The best adsorption result was obtained in the variation of the membrane with the addition of 3.84 g of polysulfone that had pores according to the size of Au. The selectivity results of the Au/Cd mixture solution in NIM and IIM were 17.802 and 36.265. In the mixture of Au/Cu, the NIM and IIM selectivity was 2.386 and 6.886, and in the mixed solution of Au/Fe, the selectivity of NIM and IIM was 0 and 8.489. Thus, the selectivity of IIM towards Au is bigger than NIM.

7.
Sci Rep ; 9(1): 18033, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31776440

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

8.
Sci Rep ; 8(1): 15317, 2018 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-30333574

RESUMEN

Describing life history dynamics of functionally important species is critical for successful management. Barrel sponges (Xestospongia spp.) fill ecologically important roles on coral reefs due to their large size and water column interactions. Studies of Caribbean X. muta suggest they may be up to 1000 s of years old. However, nothing is known of barrel sponge growth rates outside the Caribbean. We assessed Indo-Pacific barrel sponge demography with a focus on specific growth rate (SGR), density, and mean volume across four sites of varying habitat quality. Four growth models were compared using Akaike's Information Criterion using a multi-model inference approach. Age was extrapolated and validated based on sponge size on a shipwreck of known age. Sponges from different sites showed differences in density, volume gained, and mean volume, but not growth rates. Interestingly, SGRs were slightly slower than that of X. muta, yet growth models supported rapid growth; Indo-Pacific sponges were over twice as old as published estimates of comparably sized X. muta (53-55 as compared to 23 years of age, respectively), although extrapolation errors are likely to increase with sponge size. This suggests that barrel sponge growth rates in the Indo-Pacific might be more comparable to Pines rather than Redwoods.


Asunto(s)
Longevidad , Xestospongia/crecimiento & desarrollo , Animales , Arrecifes de Coral , Ecosistema , Océano Índico , Océano Pacífico , Xestospongia/fisiología
9.
Mar Pollut Bull ; 135: 466-474, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30301060

RESUMEN

Watershed-based pollution is a common form of coral reef degradation. Affected reefs are often highly turbid, where light-limitation confines the distribution of photosynthetic benthic taxa and the capacity for photoacclimation is important for survival. We investigated low light photoacclimation in a Symbiodinium-hosting bioeroding sponge using in situ PAM fluorometry. Cliona aff. viridis was artificially shaded (70 & 95% ambient light reduction) on a low turbidity Indonesian reef for 25 days, with a subsequent 14-day recovery period. Significant changes in rETRmax, and qP, and a non-significant but observable decline in Ek, demonstrated that C. aff. viridis is able to photoacclimate to conditions of extreme light reduction and recover within a relatively short period of time. The sponge is therefore unlikely to be light limited on even the most turbid reefs. However, other aspects of watershed-pollution such as sedimentation may still limit their distribution in affected coastal waters.


Asunto(s)
Aclimatación , Arrecifes de Coral , Poríferos/fisiología , Animales , Antozoos , Luz , Fotosíntesis
10.
RSC Adv ; 8(67): 38376-38383, 2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-35559085

RESUMEN

In this study, carbon dots synthesized from bamboo leaf cellulose were used simultaneously as a staining agent and for doxorubicin delivery to target cancer cells. Owing to their nontoxic properties, the production of carbon dots from bamboo leaves is a green approach involving optimized application of bamboo tree waste. For multifunctional applications, the carbon dots were modified with 4-carboxybenzylboronic acid and doxorubicin to improve target specificity and drug delivery to HeLa tumor cells. The resulting modified carbon dots were characterized using different analytical techniques, which showed that they were biocompatible, nontoxic, and highly stable over a wide range of pH values and at high ionic strengths. Furthermore, in vitro confocal microscopy studies demonstrated their blue fluorescence and cellular pathway for entering HeLa cells via folate receptor-mediated endocytosis. Cell viability data and flow cytometry results also confirmed the selective uptake of the carbon dots by HeLa cells, which significantly enhanced cell cytotoxicity.

12.
PLoS One ; 9(3): e91635, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24651687

RESUMEN

While estimates of connectivity are important for effective management, few such estimates are available for reef invertebrates other than for corals. Barrel sponges are one of the largest and most conspicuous members of the coral reef fauna across the Indo-Pacific and given their large size, longevity and ability to process large volumes of water, they have a major role in reef functioning. Here we used a panel of microsatellite markers to characterise the genetic structure of two barrel sponge species, Xestospongia testudinaria and a currently undescribed Xestospongia species. We sampled across seven populations in the Wakatobi Marine National Park, SE Sulawesi (Indonesia) spanning a spatial scale of approximately 2 to 70 km, and present the first estimates of demographic connectivity for coral reef sponges. Genetic analyses showed high levels of genetic differentiation between all populations for both species, but contrasting patterns of genetic structuring for the two species. Autocorrelation analyses showed the likely dispersal distances of both species to be in the order of 60 and 140 m for Xestopongia sp. and Xestospongia testudinaria, respectively, which was supported by assignment tests that showed high levels of self-recruitment (>80%). We also found consistently high inbreeding coefficients across all populations for both species. Our study highlights the potential susceptibility of barrel sponges to environmental perturbations because they are generally long-lived, slow growing, have small population sizes and are likely to be reliant on self-recruitment. Surprisingly, despite these features we actually found the highest abundance of both barrel sponge species (although they were generally smaller) at a site that has been severely impacted by humans over the last fifty years. This suggests that barrel sponges exhibit environmental adaptation to declining environmental quality and has important implications for the management and conservation of these important reef species.


Asunto(s)
Distribución Animal/fisiología , Conservación de los Recursos Naturales , Clima Tropical , Xestospongia/fisiología , Alelos , Animales , Teorema de Bayes , Tamaño Corporal , Análisis por Conglomerados , Intervalos de Confianza , Variación Genética , Genética de Población , Geografía , Indonesia , Repeticiones de Microsatélite/genética , Análisis de Componente Principal , Xestospongia/genética
13.
Artículo en Inglés | WPRIM | ID: wpr-626396

RESUMEN

Quality is the most important element in the process of production or services produced by organization to its customers. Quality of service refers to the measure of how a service is delivered matches customer expectations. The study aims to examine the quality of public health services received by immigrant labours. There are three aspects of quality in public health services to be measured i.e health service condition, the waiting time for treatment and treatment by hospital staff on immigrant labours. The result showed a large number of immigrant labours are satisfi ed with the quality of health services

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