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1.
Annu Rev Neurosci ; 46: 259-280, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-36972612

RESUMO

Radial cell columns are a hallmark feature of cortical architecture in many mammalian species. It has long been held, based on the lack of orientation columns, that such functional units are absent in rodent primary visual cortex (V1). These observations led to the view that rodent visual cortex has a fundamentally different network architecture than that of carnivores and primates. While columns may be lacking in rodent V1, we describe in this review that modular clusters of inputs to layer 1 and projection neurons in the layers below are prominent features of the mouse visual cortex. We propose that modules organize thalamocortical inputs, intracortical processing streams, and transthalamic communications that underlie distinct sensory and sensorimotor functions.


Assuntos
Córtex Visual , Camundongos , Animais , Retroalimentação , Córtex Visual/fisiologia , Interneurônios , Sensação , Vias Visuais/fisiologia , Mamíferos
2.
Proc Natl Acad Sci U S A ; 121(14): e2310513121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498724

RESUMO

Climate change is affecting the phenology of organisms and ecosystem processes across a wide range of environments. However, the links between organismal and ecosystem process change in complex communities remain uncertain. In snow-dominated watersheds, snowmelt in the spring and early summer, followed by a long low-flow period, characterizes the natural flow regime of streams and rivers. Here, we examined how earlier snowmelt will alter the phenology of mountain stream organisms and ecosystem processes via an outdoor mesocosm experiment in stream channels in the Eastern Sierra Nevada, California. The low-flow treatment, simulating a 3- to 6-wk earlier return to summer baseflow conditions projected under climate change scenarios in the region, increased water temperature and reduced biofilm production to respiration ratios by 32%. Additionally, most of the invertebrate species explaining community change (56% and 67% of the benthic and emergent taxa, respectively), changed in phenology as a consequence of the low-flow treatment. Further, emergent flux pulses of the dominant insect group (Chironomidae) almost doubled in magnitude, benefitting a generalist riparian predator. Changes in both invertebrate community structure (composition) and functioning (production) were mostly fine-scale, and response diversity at the community level stabilized seasonally aggregated responses. Our study illustrates how climate change in vulnerable mountain streams at the rain-to-snow transition is poised to alter the dynamics of stream food webs via fine-scale changes in phenology-leading to novel predator-prey "matches" or "mismatches" even when community structure and ecosystem processes appear stable at the annual scale.


Assuntos
Mudança Climática , Ecossistema , Animais , Rios , Temperatura , Invertebrados , Estações do Ano
3.
Proc Natl Acad Sci U S A ; 120(18): e2120252120, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094134

RESUMO

Streams in urbanizing watersheds are threatened by economic development that can lead to excessive sediment erosion and surface runoff. These anthropogenic stressors diminish valuable ecosystem services and result in pervasive degradation commonly referred to as "urban stream syndrome." Understanding how the public perceives and values improvements in stream conditions is necessary to support efforts to quantify the economic benefits of water quality improvements. We develop an ecological production framework that translates measurable indicators of stream water quality into ecological endpoints. Our interdisciplinary approach integrates a predictive hierarchical water quality model that is well suited for sparse data environments, an expert elicitation that translates measurable water quality indicators into ecological endpoints that focus group participants identified as most relevant, and a stated preference survey that elicits the public's willingness to pay for changes in these endpoints. To illustrate our methods, we develop an application to the Upper Neuse River Watershed located in the rapidly developing Triangle region of North Carolina (the United States). Our results suggest, for example, that residents are willing to pay roughly $127 per household and $54 million per year in aggregate (2021 US$) for water quality improvements resulting from a stylized intervention that increases stream bank canopy cover by 25% and decreases runoff from impervious surfaces, leading to improvements in water quality and ecological endpoints for local streams. Although the three components of our analysis are conducted with data from North Carolina, we discuss how our findings are generalizable to urban and urbanizing areas across the larger Piedmont ecoregion of the Eastern United States.

4.
Proc Natl Acad Sci U S A ; 120(18): e2120259119, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094141

RESUMO

The US Environmental Protection Agency (EPA) uses a water quality index (WQI) to estimate benefits of proposed Clean Water Act regulations. The WQI is relevant to human use value, such as recreation, but may not fully capture aspects of nonuse value, such as existence value. Here, we identify an index of biological integrity to supplement the WQI in a forthcoming national stated preference survey that seeks to capture existence value of streams and lakes more accurately within the conterminous United States (CONUS). We used literature and focus group research to evaluate aquatic indices regularly reported by the EPA's National Aquatic Resource Surveys. We chose an index that quantifies loss in biodiversity as the observed-to-expected (O/E) ratio of taxonomic composition because focus group participants easily understood its meaning and the environmental changes that would result in incremental improvements. However, available datasets of this index do not provide the spatial coverage to account for how conditions near survey respondents affect their willingness to pay for its improvement. Therefore, we modeled and interpolated the values of this index from sampled sites to 1.1 million stream segments and 297,071 lakes across the CONUS to provide the required coverage. The models explained 13 to 36% of the variation in O/E scores and demonstrate how modeling can provide data at the required density for benefits estimation. We close by discussing future work to improve performance of the models and to link biological condition with water quality and habitat models that will allow us to forecast changes resulting from regulatory options.


Assuntos
Biodiversidade , Ecossistema , Estados Unidos , Humanos , Qualidade da Água , Rios , Lagos , Monitoramento Ambiental/métodos
5.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36464485

RESUMO

Due to the increasing importance of graphs and graph streams in data representation in today's era, concept drift detection in graph streaming scenarios is more important than ever. Contributions to concept drift detection in graph streams are minimal and practically non-existent in the field of toxicology. This paper applied the discriminative subgraph-based drift detector (DSDD) to graph streams generated from real-world toxicology datasets. We used four toxicology datasets, each of which yielded two graph streams - one with abrupt drift points and one with gradual drift points. We used DSDD both with the standard minimum description length (MDL) heuristic and after replacing MDL with a much simpler heuristic SIZE (number of vertices + number of edges), and applied it to all generated graph streams containing abrupt drift points and gradual drift points for varying window sizes. Following that, we compared and analyzed the results. Finally, we applied a long short-term memory based graph stream classification model to all the generated streams and compared the difference in the performances obtained with and without detecting drift using DSDD. We believe that the results and analysis presented in this paper will provide insight into the task of concept drift detection in the toxicology domain and aid in the application of DSDD in a variety of scenarios.

6.
Glob Chang Biol ; 30(7): e17394, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988095

RESUMO

Water-logged peatlands store tremendous amounts of soil carbon (C) globally, accumulating C over millennia. As peatlands become disturbed by human activity, these long-term C stores are getting destabilized and ultimately released as greenhouse gases that may exacerbate climate change. Oxidation of the dissolved organic carbon (DOC) mobilized from disturbed soils to streams and canals may be one avenue for the transfer of previously stored, millennia-aged C to the atmosphere. However, it remains unknown whether aged peat-derived DOC undergoes oxidation to carbon dioxide (CO2) following disturbance. Here, we use a new approach to measure the radiocarbon content of CO2 produced from the oxidation of DOC in canals overlying peatland soils that have undergone widespread disturbance in Indonesia. This work shows for the first time that aged DOC mobilized from drained and burned peatland soils is susceptible to oxidation by both microbial respiration and photomineralization over aquatic travel times for DOC. The bulk radiocarbon age of CO2 produced during canal oxidation ranged from modern to ~1300 years before present. These ages for CO2 were most strongly influenced by canal water depth, which was proportional to the water table level where DOC is mobilized from disturbed soils to canals. Canal microbes preferentially respired older or younger organic C pools to CO2, and this may have been facilitated by the use of a small particulate organic C pool over the dissolved pool. Given that high densities of canals are generally associated with lower water tables and higher fire risk, our findings suggest that peatland areas with high canal density may be a hotspot for the loss of aged C on the landscape. Taken together, the results of this study show how and why aquatic processing of organic C on the landscape can enhance the transfer of long-term peat C stores to the atmosphere following disturbance.


Assuntos
Dióxido de Carbono , Carbono , Solo , Solo/química , Dióxido de Carbono/análise , Carbono/análise , Indonésia , Oxirredução
7.
Chem Rec ; 24(8): e202300333, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39051717

RESUMO

Global agricultural by-products usually go to waste, especially in developing countries where agricultural products are usually exported as raw products. Such waste streams, once converted to "value-added" products could be an additional source of revenue while simultaneously having positive impacts on the socio-economic well-being of local people. We highlight the utilization of thermochemical techniques to activate and convert agricultural waste streams such as rice and straw husk, coconut fiber, coffee wastes, and okara power wastes commonly found in the world into porous activated carbons and biofuels. Such activated carbons are suitable for various applications in environmental remediation, climate mitigation, energy storage, and conversions such as batteries and supercapacitors, in improving crop productivity and producing useful biofuels.


Assuntos
Agricultura , Biocombustíveis , Biocombustíveis/análise , Carvão Vegetal/química , Resíduos/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-38629951

RESUMO

Three Gram-stain-negative, aerobic, rod-shaped, non-motile strains (DC2WT, DC25WT, and LKC2W) were isolated from streams in China. Comparisons based on the 16S rRNA gene sequences showed that these three strains share 16S rRNA gene sequence similarity values over 97.0 % with the species of genus Arcicella. There was confusion due to the fact that all species of genera Flectobacillus, Aquirufa, and Sandaracinomonas show 16S rRNA gene sequence similarity of over 90.0 % to the above three strains, but the genus Flectobacillus belongs to the family Spirosomataceae and the genera Aquirufa and Sandaracinomonas belong to the family Cytophagaceae. Observing the phylogenetic trees, strains DC2WT, DC25WT, and LKC2W cluster closely with the species of genus Arcicella, but some species within the families Spirosomataceae and Cytophagaceae are not monophyletic. The phylogenomic tree also showed a confused phylogenetic relationships among these non-monophyletic species. Combining the phylogenetic relationships and average nucleotide identity values, the current taxonomic status of all the genera within the families Spirosomataceae and Cytophagaceae were re-examined. The genera 'Chryseosolibacter', 'Dawidia', and Chryseotalea should belong to the new family Chryseotaleaceae fam. nov., the genera Arcicella, Flectobacillus, Pseudarcicella, Aquirufa, and Sandaracinomonas should belong to the new family Flectobacillaceae fam. nov., the genera Fluviimonas, Taeseokella, Arcticibacterium, Emticicia, Jiulongibacter, Marinilongibacter, Lacihabitans, and Leadbetterella should belong to the new family Leadbetterellaceae fam. nov., the genus Litoribacter should be reassigned to the family Cyclobacteriaceae, and the genera Arundinibacter and Tellurirhabdus should be reassigned to the family Spirosomataceae. Strains DC2WT and DC25WT are reported to represent two novel species of the genus Arcicella, for which the names Arcicella gelida sp. nov. (type strain DC2WT=GDMCC 1.3209T=KCTC 92559T) and Arcicella lustrica sp. nov. (type strain DC25WT=GDMCC 1.3210T=KCTC 92557T) are proposed.


Assuntos
Cytophagaceae , Humanos , Rios , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Bacteroidetes , China
9.
Artigo em Inglês | MEDLINE | ID: mdl-39196633

RESUMO

Four Gram-stain-negative, aerobic, rod-shaped and motile strains (LYT19WT, DXS22WT, DXS29WT and BYS139WT) were isolated from streams in China. All four strains showed highest 16S rRNA gene sequence similarities to the species of genus Ideonella. The calculated average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values among strains LYT19WT, DXS22WT, DXS29WT, BYS139WT and other closely related strains were less than 79.5, 22.5 and 74.0%, respectively, indicating that each of the four strains should represent an independent novel species. The further reconstructed phylogenomic tree showed that strains LYT19WT and DXS29WT clustered closely with Ideonella strains, but strains DXS22WT and BYS139WT formed an independent clade with Aquabacterium terrae and Aquabacterium pictum. Comparing with other Aquabacterium species, A. terrae and A. pictum harboured distinct physiological and genetic characteristics, so it was reasonable to propose a novel genus Pseudaquabacterium to accommodate A. terrae, A. pictum, DXS22WT and BYS139WT. The major fatty acids of the four strains contained C16 : 0, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c). The predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and one unidentified aminophospholipid. Combining above descriptions, strains LYT19WT and DXS29WT should represent two novel species of the genus Ideonella, for which the names Ideonella margarita sp. nov. (type strain LYT19WT=GDMCC 1.3205T=KCTC 92545T) and Ideonella lacteola sp. nov. (type strain DXS29WT=GDMCC 1.3207T=KCTC 92547T) are proposed, respectively. Strains DXS22WT and BYS139WT should represent two novel species of the new genus Pseudaquabacterium, for which the names Pseudaquabacterium inlustre sp. nov. (type strain DXS22WT=GDMCC 1.3206T=KCTC 92546T) and Pseudaquabacterium rugosum sp. nov. (type strain BYS139WT=GDMCC 1.3208T=KCTC 92548T) are proposed, respectively.


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Rios , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , China , Ácidos Graxos/análise , DNA Bacteriano/genética , Rios/microbiologia
10.
Microb Cell Fact ; 23(1): 29, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245756

RESUMO

BACKGROUND: Industrial by-products accrue in most agricultural or food-related production processes, but additional value chains have already been established for many of them. Crude glycerol has a 60% lower market value than commercial glucose, as large quantities are produced in the biodiesel industry, but its valorisation is still underutilized. Due to its high carbon content and the natural ability of many microorganisms to metabolise it, microbial upcycling is a suitable option for this waste product. RESULTS: In this work, the use of crude glycerol for the production of the value-added compound itaconate is demonstrated using the smut fungus Ustilago maydis. Starting with a highly engineered strain, itaconate production from an industrial glycerol waste stream was quickly established on a small scale, and the resulting yields were already competitive with processes using commercial sugars. Adaptive laboratory evolution resulted in an evolved strain with a 72% increased growth rate on glycerol. In the subsequent development and optimisation of a fed-batch process on a 1.5-2 L scale, the use of molasses, a side stream of sugar beet processing, eliminated the need for other expensive media components such as nitrogen or vitamins for biomass growth. The optimised process was scaled up to 150 L, achieving an overall titre of 72 g L- 1, a yield of 0.34 g g- 1, and a productivity of 0.54 g L- 1 h- 1. CONCLUSIONS: Pilot-scale itaconate production from the complementary waste streams molasses and glycerol has been successfully established. In addition to achieving competitive performance indicators, the proposed dual feedstock strategy offers lower process costs and carbon footprint for the production of bio-based itaconate.


Assuntos
Glicerol , Succinatos , Glicerol/metabolismo , Succinatos/metabolismo , Glucose/metabolismo
11.
Microb Ecol ; 87(1): 28, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38182675

RESUMO

High mountain freshwater systems are particularly sensitive to the impacts of global warming and relevant environmental changes. Microorganisms contribute substantially to biogeochemical processes, yet their distribution patterns and driving mechanism in alpine streams remain understudied. Here, we examined the bacterial and fungal community compositions in stream biofilm along the elevational gradient of 745-1874 m on Mt. Kilimanjaro and explored their alpha and beta diversity patterns and the underlying environmental drivers. We found that the species richness and evenness monotonically increased towards higher elevations for bacteria, while were non-significant for fungi. However, both bacterial and fungal communities showed consistent elevational distance-decay relationships, i.e., the dissimilarity of assemblage composition increased with greater elevational differences. Bacterial alpha diversity patterns were mainly affected by chemical variables such as total nitrogen and phosphorus, while fungi were affected by physical variables such as riparian shading and stream width. Notably, climatic variables such as mean annual temperature strongly affected the elevational succession of bacterial and fungal community compositions. Our study is the first exploration of microbial biodiversity and their underlying driving mechanisms for stream ecosystems in tropical alpine regions. Our findings provide insights on the response patterns of tropical aquatic microbial community composition and diversity under climate change.


Assuntos
Microbiota , Rios , Tanzânia , Bactérias/genética , Biofilmes
12.
Neurocase ; 30(1): 8-17, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38700140

RESUMO

Mary, who experienced non-fluent aphasia as a result of an ischemic stroke, received 10 years of personalized language training (LT), resulting in transient enhancements in speech and comprehension. To enhance these effects, multisite transcranial Direct Current Stimulation (tDCS) was added to her LT regimen for 15 sessions. Assessment using the Reliable Change Index showed that this combination improved her left inferior frontal connectivity and speech production for two months and significantly improved comprehension after one month. The results indicate that using multisite transcranial direct current stimulation (tDCS) can improve the effectiveness of language therapy (LT) for individuals with non-fluent aphasia.


Assuntos
Terapia da Linguagem , Estimulação Transcraniana por Corrente Contínua , Feminino , Humanos , Afasia/etiologia , Afasia/reabilitação , Afasia/diagnóstico por imagem , Afasia/terapia , Neuroimagem Funcional , AVC Isquêmico/complicações , AVC Isquêmico/reabilitação , AVC Isquêmico/diagnóstico por imagem , Terapia da Linguagem/métodos , Acidente Vascular Cerebral/complicações , Reabilitação do Acidente Vascular Cerebral/métodos
13.
Oecologia ; 204(2): 401-411, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37486411

RESUMO

Increases in the intensity and frequency of wildfires highlight the need to understand how fire disturbance affects ecological interactions. Though the effects of wildfire on free-living aquatic communities are relatively well-studied, how host-parasite interactions respond to fire disturbance is largely unexplored. Using a Before-After-Control-Impact design, we surveyed 10 stream sites (5 burned and 5 unburned) in the Willamette River Basin, Oregon and quantified snail host infection status and trematode parasite community structure 1 year before and two years after historic wildfires. Despite the severity of the wildfires, snail host populations did not show significant shifts in density or size distributions. We detected nine taxa of trematode parasites and overall probability of infection remained consistent over the three-year study period. However, at the taxon-specific level, we found evidence that infection probability by one trematode decreased and another increased after fire. In a larger dataset focusing on the first year after fire (9 burned, 8 unburned sites), we found evidence for subtle differences in trematode community structure, including higher Shannon diversity and evenness at the burned sites. Taken together, host-parasite interactions were remarkably stable for most taxa; for trematodes that did show responses, changes in abundance or behavior of definitive hosts may underlie observed patterns. These results have implications for using parasites as bioindicators of environmental change and suggest that aquatic snail-trematode interactions may be relatively resistant to wildfire disturbance in some ecosystems.


Assuntos
Rios , Incêndios Florestais , Interações Hospedeiro-Parasita , Ecossistema , Água Doce
14.
Cereb Cortex ; 33(10): 6207-6227, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36573464

RESUMO

To understand auditory cortical processing, the effective connectivity between 15 auditory cortical regions and 360 cortical regions was measured in 171 Human Connectome Project participants, and complemented with functional connectivity and diffusion tractography. 1. A hierarchy of auditory cortical processing was identified from Core regions (including A1) to Belt regions LBelt, MBelt, and 52; then to PBelt; and then to HCP A4. 2. A4 has connectivity to anterior temporal lobe TA2, and to HCP A5, which connects to dorsal-bank superior temporal sulcus (STS) regions STGa, STSda, and STSdp. These STS regions also receive visual inputs about moving faces and objects, which are combined with auditory information to help implement multimodal object identification, such as who is speaking, and what is being said. Consistent with this being a "what" ventral auditory stream, these STS regions then have effective connectivity to TPOJ1, STV, PSL, TGv, TGd, and PGi, which are language-related semantic regions connecting to Broca's area, especially BA45. 3. A4 and A5 also have effective connectivity to MT and MST, which connect to superior parietal regions forming a dorsal auditory "where" stream involved in actions in space. Connections of PBelt, A4, and A5 with BA44 may form a language-related dorsal stream.


Assuntos
Córtex Auditivo , Humanos , Córtex Auditivo/diagnóstico por imagem , Lobo Temporal , Lobo Parietal , Semântica , Idioma
15.
Cereb Cortex ; 33(20): 10686-10701, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689834

RESUMO

The hierarchical organization between 25 ventral stream visual cortical regions and 180 cortical regions was measured with magnetoencephalography using the Human Connectome Project Multimodal Parcellation atlas in 83 Human Connectome Project participants performing a visual memory task. The aim was to reveal the hierarchical organization using a whole-brain model based on generative effective connectivity with this fast neuroimaging method. V1-V4 formed a first group of interconnected regions. Especially V4 had connectivity to a ventrolateral visual stream: V8, the fusiform face cortex, and posterior inferior temporal cortex PIT. These regions in turn had effectivity connectivity to inferior temporal cortex visual regions TE2p and TE1p. TE2p and TE1p then have connectivity to anterior temporal lobe regions TE1a, TE1m, TE2a, and TGv, which are multimodal. In a ventromedial visual stream, V1-V4 connect to ventromedial regions VMV1-3 and VVC. VMV1-3 and VVC connect to the medial parahippocampal gyrus PHA1-3, which, with the VMV regions, include the parahippocampal scene area. The medial parahippocampal PHA1-3 regions have connectivity to the hippocampal system regions the perirhinal cortex, entorhinal cortex, and hippocampus. These effective connectivities of two ventral visual cortical streams measured with magnetoencephalography provide support to the hierarchical organization of brain systems measured with fMRI, and new evidence on directionality.


Assuntos
Magnetoencefalografia , Lobo Temporal , Humanos , Lobo Temporal/diagnóstico por imagem , Hipocampo , Giro Para-Hipocampal , Córtex Entorrinal , Imageamento por Ressonância Magnética
16.
J Phycol ; 60(1): 15-25, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37948315

RESUMO

The relative frequency of sexual versus asexual reproduction governs the distribution of genetic diversity within and among populations. Most studies on the consequences of reproductive variation focus on the mating system (i.e., selfing vs. outcrossing) of diploid-dominant taxa (e.g., angiosperms), often ignoring asexual reproduction. Although reproductive systems are hypothesized to be correlated with life-cycle types, variation in the relative rates of sexual and asexual reproduction remains poorly characterized across eukaryotes. This is particularly true among the three major lineages of macroalgae (green, brown, and red). The Rhodophyta are particularly interesting, as many taxa have complex haploid-diploid life cycles that influence genetic structure. Though most marine reds have separate sexes, we show that freshwater red macroalgae exhibit patterns of switching between monoicy and dioicy in sister taxa that rival those recently shown in brown macroalgae and in angiosperms. We advocate for the investigation of reproductive system evolution using freshwater reds, as this will expand the life-cycle types for which these data exist, enabling comparative analyses broadly across eukaryotes. Unlike their marine cousins, species in the Batrachospermales have macroscopic gametophytes attached to filamentous, often microscopic sporophytes. While asexual reproduction through monospores may occur in all freshwater reds, the Compsopogonales are thought to be exclusively asexual. Understanding the evolutionary consequences of selfing and asexual reproduction will aid in our understanding of the evolutionary ecology of all algae and of eukaryotic evolution generally.


Assuntos
Alga Marinha , Alga Marinha/genética , Reprodução , Reprodução Assexuada , Água Doce , Genitália
17.
Mar Drugs ; 22(6)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38921572

RESUMO

Utilization of fish rest raw material for fish oil extraction has received interest with the increasing demand for sustainable food sources. Enzymatic hydrolysis is an efficient method for the extraction of value-added compounds, but its effectiveness may be enhanced by high-pressure processing (HPP). However, HPP can induce lipid oxidation, affecting the quality of the oil. This study aimed to evaluate the quality of fish oil obtained after enzymatic hydrolysis of a mixture of rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar) rest raw material pretreated by HPP. Six pretreatments were tested prior to enzymatic hydrolysis; 200 MPa × 4 min, 200 MPa × 8 min, 400 MPa × 4 min, 400 MPa × 8 min, 600 MPa × 4 min, and 600 MPa × 8 min. The oil samples were analyzed for lipid oxidation parameters, free fatty acid content, fatty acid composition, and color changes over 8 weeks. The results confirmed that HPP may induce lipid oxidation and revealed significant influence of HPP parameters on lipid oxidation, with higher pressures leading to increased oxidation. Fatty acid composition varied among samples, but it was not substantially affected by HPP.


Assuntos
Ácidos Graxos , Óleos de Peixe , Oncorhynchus mykiss , Salmo salar , Animais , Oncorhynchus mykiss/metabolismo , Óleos de Peixe/química , Hidrólise , Ácidos Graxos/análise , Pressão , Oxirredução
18.
Risk Anal ; 44(3): 686-704, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37666505

RESUMO

A wide variety of weather conditions, from windstorms to prolonged heat events, can substantially impact power systems, posing many risks and inconveniences due to power outages. Accurately estimating the probability distribution of the number of customers without power using data about the power utility system and environmental and weather conditions can help utilities restore power more quickly and efficiently. However, the critical shortcoming of current models lies in the difficulties of handling (i) data streams and (ii) model uncertainty due to combining data from various weather events. Accordingly, this article proposes an adaptive ensemble learning algorithm for data streams, which deploys a feature- and performance-based weighting mechanism to adaptively combine outputs from multiple competitive base learners. As a proof of concept, we use a large, real data set of daily customer interruptions to develop the first adaptive all-weather outage prediction model using data streams. We benchmark several approaches to demonstrate the advantage of our approach in offering more accurate probabilistic predictions. The results show that the proposed algorithm reduces the probabilistic predictions' error of the base learners between 4% and 22% with an average of 8%, which also result in substantially more accurate point predictions. The improvement made by our algorithm is enhanced as we exchange base learners with simpler models.

19.
Health Res Policy Syst ; 22(1): 90, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103903

RESUMO

BACKGROUND: Despite high overall COVID-19 vaccine coverage, the continuously low elderly vaccination rate in mainland China remains a dangerous threat as the country shifts away from its zero-Covid policy. This retrospective study uses the Multiple Streams Framework to examine how macro-level factors may explain poor elderly vaccination outcomes. METHODS: We performed a thematic analysis of qualitative data obtained from 95 official press conferences from October 20, 2020, to February 27, 2023, vaccination-related policy documents, and media coverage, using both inductive and deductive coding approaches. RESULTS: Our findings suggest that in the problem stream, elderly vaccination was not a "focusing event" during the initial vaccine rollout, resulting in delayed outreach to this population. Additionally, ideologically driven complacency and discrepancies in top-down implementation undermined elderly vaccination in the political stream. In the policy stream, precautious and ambiguous statements, inconsistent policy content, radical shifting media messages, and less age-friendly digital technologies also affected elderly vaccination. CONCLUSIONS: The poor convergence of the three streams led the elderly to be the Achilles' heel of China's COVID-19 containment strategy. Future studies should focus on priority identification, adoption of enforcement measures, and timely and effective policy dissemination. The empirical lessons from China can inform and optimize elderly vaccination policy design and implementation in the post-pandemic era.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Política de Saúde , SARS-CoV-2 , Cobertura Vacinal , Vacinação , Humanos , China , COVID-19/prevenção & controle , Idoso , Estudos Retrospectivos , Idoso de 80 Anos ou mais
20.
Health Res Policy Syst ; 22(1): 106, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143555

RESUMO

BACKGROUND: Since 2006, Taiwan has actively pursued the development of its medical tourism industry. In 2013, the government sought to bolster this sector by integrating medical tourism into the Free Economic Pilot Zones. Despite narrowly missing the mark, the initiative failed to materialize into law. This qualitative study endeavors to discern the pertinent factors influencing the agenda-setting process for incorporating medical tourism into the Free Economic Pilot Zones in Taiwan. METHODS: A comprehensive examination of policies concerning the legitimation of medical tourism within the Free Economic Pilot Zones was undertaken through semi-structured interviews and a thorough review of policy documents. Key informants were strategically selected using purposive and snowball sampling techniques. Thematic analysis was applied to scrutinize the amassed data and organize it within the framework of Kingdon's multiple streams. RESULTS: In the problem stream, increasing financial strains and cost containment pressures under the National Health Insurance program have long driven health care providers to seek further opportunities in medical tourism. The existing barriers to expanding medical tourism in Taiwan included diplomatic tensions (specifically cross-strait relations), public concerns about commercialization of medical care and reduced their access to care, and legal and language barriers. Within the policy stream, factors such as franchise fees to support national health insurance, limited number of demonstration medical tourism sites and services allowed, the allowance of foreign medical personnel, regulations governing domestic physicians, the importance of demonstration, regulation, and accreditation, as well as restrictions on investment from China, were emphasized. The politics stream highlights factors such as governmental support, opposition from opposing parties, public concerns and critics from academia and non-governmental organizations, and skepticism from medical faculties. CONCLUSION: Acknowledging the recognized challenges in enacting the medical tourism provision of the Free Economic Pilot Zones Special Act and emphasizing the political will of leadership, a viable policy solution remained elusive. Although a window of opportunity existed for the passage of the bill, it waned as public concerns sidelined the issue from the national agenda. The Taiwan case underscores the necessity for meticulous consideration of issues, proposed solutions, and political dynamics to achieve successful policy enactment.


Assuntos
Política de Saúde , Turismo Médico , Formulação de Políticas , Taiwan , Humanos , Programas Nacionais de Saúde , Acessibilidade aos Serviços de Saúde , Pesquisa Qualitativa , Atenção à Saúde
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