48 research outputs found
Extracting phycocyanin from spirulina and hydrothermal liquefaction of its residues to produce bio-crude oil
Microalgae is a promising biofuel source with high photosynthetic efficiency, and it often contains high-value substances for nutritional, pharmaceutical and medical applications. In order to improve the economic viability of the spirulina utilization, this study investigated a cost competitive biotechnological process for C-phycocyanin (C-PC) extraction from spirulina platensis. The residual biomass after C-PC extraction was converted into bio-crude oil via hydrothermal liquefaction (HTL). The HTL bio-crude oil obtained from the original spirulina feedstock and the residual after the C-PC extraction were compared.
A rapid and efficient process for extraction and purification of food-level C-PC from spirulina platensis was developed in this study. The process conditions include: 1) freeze the spirulina 3 hours to extract the crude protein; 2) add 80 g/L (w/v) activated carbon to the crude extract; 3) use a vacuum filter with a 0.22 μm pore size membrane to collect the extract; and 4) freeze dry the extract to get the C-PC powder. The yield of the C-PC production is 27% and the cost (exclude labor) for entire process is $26.1/kg. After C-PC extraction, there is still 63% dry biomass left which was used for conversion into bio-crude oil via HTL.
The HTL bio-oil products distribution as well as their composition, reaction pathways and energy recovery via HTL were investigated. HTL was conducted at temperatures range from 260˚C to 300˚C at 0.7 MPa N2 initial pressures. The highest bio-crude oil yield of 38 % (based on dry volatile matter) was obtained at 300˚C. The highest higher heating value is 37.1 MJ/kg occurred at 300°C reaction temperature. Elemental analysis revealed that the decarboxylation and denitrification may be dominant from 260˚C to 300°C following repolymerization governing at higher temperature; TG analysis showed that approximately 75.4 % distilled bio-crude products were in the range of 200-550°C. These distillates can be further upgraded for transportation fuels
The Prevalence of Metabolically Healthy and Unhealthy Obesity according to Different Criteria
Objective: Obesity-related disease risks may vary depending on whether the subject has metabolically healthy obesity (MHO) or metabolically unhealthy obesity (MUO). At least 5 definitions/criteria of obesity and metabolic disorders have been documented in the literature, yielding uncertainties in a reliable international comparison of obesity phenotype prevalence. This report aims to compare differences in MHO and MUO prevalence according to the 5 most frequently used definitions. Methods: A random sample of 4,757 adults aged 35 years and older (male 51.1%) was enrolled. Obesity was defined either according to body mass index or waist circumference, and the definitions of metabolic abnormalities were derived from 5 different criteria. Results: In MHO, the highest prevalence was obtained when using the homeostasis model assessment (HOMA) criteria (13.6%), followed by the Chinese Diabetes Society (11.4%), Adult Treatment Panel III (10.3%), Wildman (5.2%), and Karelis (4.2%) criteria; however, the MUO prevalence had an opposite trend to MHO prevalence. The magnitude of differences in the age-specific prevalence of MHO and MUO varied greatly and ranked in different orders. The proportion of insulin resistance for MHO and MUO individuals differed significantly regardless of which metabolic criterion was used. Conclusion: The prevalence of MHO and MUO in the Chinese population varies according to different definitions of obesity and metabolic disorders
Towards Artificial General Intelligence (AGI) in the Internet of Things (IoT): Opportunities and Challenges
Artificial General Intelligence (AGI), possessing the capacity to comprehend,
learn, and execute tasks with human cognitive abilities, engenders significant
anticipation and intrigue across scientific, commercial, and societal arenas.
This fascination extends particularly to the Internet of Things (IoT), a
landscape characterized by the interconnection of countless devices, sensors,
and systems, collectively gathering and sharing data to enable intelligent
decision-making and automation. This research embarks on an exploration of the
opportunities and challenges towards achieving AGI in the context of the IoT.
Specifically, it starts by outlining the fundamental principles of IoT and the
critical role of Artificial Intelligence (AI) in IoT systems. Subsequently, it
delves into AGI fundamentals, culminating in the formulation of a conceptual
framework for AGI's seamless integration within IoT. The application spectrum
for AGI-infused IoT is broad, encompassing domains ranging from smart grids,
residential environments, manufacturing, and transportation to environmental
monitoring, agriculture, healthcare, and education. However, adapting AGI to
resource-constrained IoT settings necessitates dedicated research efforts.
Furthermore, the paper addresses constraints imposed by limited computing
resources, intricacies associated with large-scale IoT communication, as well
as the critical concerns pertaining to security and privacy
Mitigating scattering effects in DMD-based microscale 3D printing using machine learning
Mitigating scattering effects in DMD-based microscale 3D printing using machine learning
Characterization of morpho-functional traits in mesophotic corals reveals optimized light capture and photosynthesis
AbstractThe morphology and skeleton architecture of photosynthetic corals modulates the light capture and functioning of the coral-algal symbiosis on shallow-water corals. Since corals can thrive on mesophotic reefs under extreme light-limited conditions, we hypothesized that microskeletal coral features optimize light capture under low-light environments. Using micro-computed tomography scanning, we conducted a comprehensive three-dimensional (3D) assessment of small-scale skeleton morphology of the depth-generalist coral Stylophora pistillata collected from shallow (5 m) and mesophotic (45 m) depths. We detected a high phenotypic diversity between depths, resulting in two distinct morphotypes, with calyx diameter, theca height, and corallite marginal spacing contributing to most of the variation between depths. To determine whether such depth-specific morphotypes affect coral light capture and photosynthesis on the corallite-scale, we developed 3D simulations of light propagation based on photosynthesis-irradiance parameters. We found that corals associated with shallow morphotypes dissipated excess light through self-shading microskeletal features; while mesophotic morphotypes facilitated enhanced light absorption and photosynthesis under low-light conditions. We conclude that the mesophotic coral architecture provides a greater ability to trap solar energy and efficiently exploit the limited light conditions, and suggest that morphological modifications play a key role in the photoadaptation response to low-light.</jats:p
Morpho-functional traits of the coral Stylophora pistillata enhance light capture for photosynthesis at mesophotic depths.
The morphological architecture of photosynthetic corals modulates the light capture and functioning of the coral-algal symbiosis on shallow-water corals. Since corals can thrive on mesophotic reefs under extreme light-limited conditions, we hypothesized that microskeletal coral features enhance light capture under low-light environments. Utilizing micro-computed tomography scanning, we conducted a novel comprehensive three-dimensional (3D) assessment of the small-scale skeleton morphology of the depth-generalist coral Stylophora pistillata collected from shallow (4-5 m) and mesophotic (45-50 m) depths. We detected a high phenotypic diversity between depths, resulting in two distinct morphotypes, with calyx diameter, theca height, and corallite marginal spacing contributing to most of the variation between depths. To determine whether such depth-specific morphotypes affect coral light capture and photosynthesis on the corallite scale, we developed 3D simulations of light propagation and photosynthesis. We found that microstructural features of corallites from mesophotic corals provide a greater ability to use solar energy under light-limited conditions; while corals associated with shallow morphotypes avoided excess light through self-shading skeletal architectures. The results from our study suggest that skeleton morphology plays a key role in coral photoadaptation to light-limited environments
Serum uric acid and impaired cognitive function in community-dwelling elderly in Beijing
3D bioprinting of complex tissues in vitro: state-of-the-art and future perspectives
AbstractThe pharmacology and toxicology of a broad variety of therapies and chemicals have significantly improved with the aid of the increasing in vitro models of complex human tissues. Offering versatile and precise control over the cell population, extracellular matrix (ECM) deposition, dynamic microenvironment, and sophisticated microarchitecture, which is desired for the in vitro modeling of complex tissues, 3D bio-printing is a rapidly growing technology to be employed in the field. In this review, we will discuss the recent advancement of printing techniques and bio-ink sources, which have been spurred on by the increasing demand for modeling tactics and have facilitated the development of the refined tissue models as well as the modeling strategies, followed by a state-of-the-art update on the specialized work on cancer, heart, muscle and liver. In the end, the toxicological modeling strategies, substantial challenges, and future perspectives for 3D printed tissue models were explored.</jats:p
